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28d81abb | 1 | /* Expands front end tree to back end RTL for GNU C-Compiler |
642cac7b | 2 | Copyright (C) 1987, 88, 89, 92-98, 1999 Free Software Foundation, Inc. |
28d81abb RK |
3 | |
4 | This file is part of GNU CC. | |
5 | ||
6 | GNU CC is free software; you can redistribute it and/or modify | |
7 | it under the terms of the GNU General Public License as published by | |
8 | the Free Software Foundation; either version 2, or (at your option) | |
9 | any later version. | |
10 | ||
11 | GNU CC is distributed in the hope that it will be useful, | |
12 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | GNU General Public License for more details. | |
15 | ||
16 | You should have received a copy of the GNU General Public License | |
17 | along with GNU CC; see the file COPYING. If not, write to | |
e9fa0c7c RK |
18 | the Free Software Foundation, 59 Temple Place - Suite 330, |
19 | Boston, MA 02111-1307, USA. */ | |
28d81abb RK |
20 | |
21 | ||
22 | /* This file handles the generation of rtl code from tree structure | |
23 | above the level of expressions, using subroutines in exp*.c and emit-rtl.c. | |
24 | It also creates the rtl expressions for parameters and auto variables | |
25 | and has full responsibility for allocating stack slots. | |
26 | ||
27 | The functions whose names start with `expand_' are called by the | |
28 | parser to generate RTL instructions for various kinds of constructs. | |
29 | ||
30 | Some control and binding constructs require calling several such | |
31 | functions at different times. For example, a simple if-then | |
32 | is expanded by calling `expand_start_cond' (with the condition-expression | |
33 | as argument) before parsing the then-clause and calling `expand_end_cond' | |
34 | after parsing the then-clause. */ | |
35 | ||
36 | #include "config.h" | |
670ee920 | 37 | #include "system.h" |
ccd043a9 | 38 | |
28d81abb RK |
39 | #include "rtl.h" |
40 | #include "tree.h" | |
41 | #include "flags.h" | |
6adb4e3a | 42 | #include "except.h" |
28d81abb RK |
43 | #include "function.h" |
44 | #include "insn-flags.h" | |
45 | #include "insn-config.h" | |
46 | #include "insn-codes.h" | |
47 | #include "expr.h" | |
48 | #include "hard-reg-set.h" | |
49 | #include "obstack.h" | |
50 | #include "loop.h" | |
51 | #include "recog.h" | |
ca695ac9 | 52 | #include "machmode.h" |
10f0ad3d | 53 | #include "toplev.h" |
d6f4ec51 | 54 | #include "output.h" |
ca695ac9 | 55 | |
28d81abb RK |
56 | #define obstack_chunk_alloc xmalloc |
57 | #define obstack_chunk_free free | |
58 | struct obstack stmt_obstack; | |
59 | ||
18543a22 ILT |
60 | /* Assume that case vectors are not pc-relative. */ |
61 | #ifndef CASE_VECTOR_PC_RELATIVE | |
62 | #define CASE_VECTOR_PC_RELATIVE 0 | |
63 | #endif | |
64 | ||
28d81abb RK |
65 | /* Filename and line number of last line-number note, |
66 | whether we actually emitted it or not. */ | |
67 | char *emit_filename; | |
68 | int emit_lineno; | |
69 | ||
70 | /* Nonzero if within a ({...}) grouping, in which case we must | |
71 | always compute a value for each expr-stmt in case it is the last one. */ | |
72 | ||
73 | int expr_stmts_for_value; | |
74 | ||
75 | /* Each time we expand an expression-statement, | |
76 | record the expr's type and its RTL value here. */ | |
77 | ||
78 | static tree last_expr_type; | |
79 | static rtx last_expr_value; | |
80 | ||
7629c936 RS |
81 | /* Each time we expand the end of a binding contour (in `expand_end_bindings') |
82 | and we emit a new NOTE_INSN_BLOCK_END note, we save a pointer to it here. | |
83 | This is used by the `remember_end_note' function to record the endpoint | |
84 | of each generated block in its associated BLOCK node. */ | |
85 | ||
86 | static rtx last_block_end_note; | |
87 | ||
28d81abb RK |
88 | /* Number of binding contours started so far in this function. */ |
89 | ||
90 | int block_start_count; | |
91 | ||
92 | /* Nonzero if function being compiled needs to | |
93 | return the address of where it has put a structure value. */ | |
94 | ||
95 | extern int current_function_returns_pcc_struct; | |
96 | ||
97 | /* Label that will go on parm cleanup code, if any. | |
98 | Jumping to this label runs cleanup code for parameters, if | |
99 | such code must be run. Following this code is the logical return label. */ | |
100 | ||
101 | extern rtx cleanup_label; | |
102 | ||
103 | /* Label that will go on function epilogue. | |
104 | Jumping to this label serves as a "return" instruction | |
105 | on machines which require execution of the epilogue on all returns. */ | |
106 | ||
107 | extern rtx return_label; | |
108 | ||
28d81abb RK |
109 | /* Offset to end of allocated area of stack frame. |
110 | If stack grows down, this is the address of the last stack slot allocated. | |
111 | If stack grows up, this is the address for the next slot. */ | |
112 | extern int frame_offset; | |
113 | ||
114 | /* Label to jump back to for tail recursion, or 0 if we have | |
115 | not yet needed one for this function. */ | |
116 | extern rtx tail_recursion_label; | |
117 | ||
118 | /* Place after which to insert the tail_recursion_label if we need one. */ | |
119 | extern rtx tail_recursion_reentry; | |
120 | ||
121 | /* Location at which to save the argument pointer if it will need to be | |
122 | referenced. There are two cases where this is done: if nonlocal gotos | |
123 | exist, or if vars whose is an offset from the argument pointer will be | |
124 | needed by inner routines. */ | |
125 | ||
126 | extern rtx arg_pointer_save_area; | |
127 | ||
128 | /* Chain of all RTL_EXPRs that have insns in them. */ | |
129 | extern tree rtl_expr_chain; | |
28d81abb RK |
130 | \f |
131 | /* Functions and data structures for expanding case statements. */ | |
132 | ||
133 | /* Case label structure, used to hold info on labels within case | |
134 | statements. We handle "range" labels; for a single-value label | |
135 | as in C, the high and low limits are the same. | |
136 | ||
5720c7e7 RK |
137 | An AVL tree of case nodes is initially created, and later transformed |
138 | to a list linked via the RIGHT fields in the nodes. Nodes with | |
139 | higher case values are later in the list. | |
28d81abb RK |
140 | |
141 | Switch statements can be output in one of two forms. A branch table | |
142 | is used if there are more than a few labels and the labels are dense | |
143 | within the range between the smallest and largest case value. If a | |
144 | branch table is used, no further manipulations are done with the case | |
145 | node chain. | |
146 | ||
147 | The alternative to the use of a branch table is to generate a series | |
148 | of compare and jump insns. When that is done, we use the LEFT, RIGHT, | |
149 | and PARENT fields to hold a binary tree. Initially the tree is | |
de14fd73 RK |
150 | totally unbalanced, with everything on the right. We balance the tree |
151 | with nodes on the left having lower case values than the parent | |
28d81abb RK |
152 | and nodes on the right having higher values. We then output the tree |
153 | in order. */ | |
154 | ||
155 | struct case_node | |
156 | { | |
157 | struct case_node *left; /* Left son in binary tree */ | |
158 | struct case_node *right; /* Right son in binary tree; also node chain */ | |
159 | struct case_node *parent; /* Parent of node in binary tree */ | |
160 | tree low; /* Lowest index value for this label */ | |
161 | tree high; /* Highest index value for this label */ | |
162 | tree code_label; /* Label to jump to when node matches */ | |
57641239 | 163 | int balance; |
28d81abb RK |
164 | }; |
165 | ||
166 | typedef struct case_node case_node; | |
167 | typedef struct case_node *case_node_ptr; | |
168 | ||
169 | /* These are used by estimate_case_costs and balance_case_nodes. */ | |
170 | ||
171 | /* This must be a signed type, and non-ANSI compilers lack signed char. */ | |
172 | static short *cost_table; | |
173 | static int use_cost_table; | |
28d81abb RK |
174 | \f |
175 | /* Stack of control and binding constructs we are currently inside. | |
176 | ||
177 | These constructs begin when you call `expand_start_WHATEVER' | |
178 | and end when you call `expand_end_WHATEVER'. This stack records | |
179 | info about how the construct began that tells the end-function | |
180 | what to do. It also may provide information about the construct | |
181 | to alter the behavior of other constructs within the body. | |
182 | For example, they may affect the behavior of C `break' and `continue'. | |
183 | ||
184 | Each construct gets one `struct nesting' object. | |
185 | All of these objects are chained through the `all' field. | |
186 | `nesting_stack' points to the first object (innermost construct). | |
187 | The position of an entry on `nesting_stack' is in its `depth' field. | |
188 | ||
189 | Each type of construct has its own individual stack. | |
190 | For example, loops have `loop_stack'. Each object points to the | |
191 | next object of the same type through the `next' field. | |
192 | ||
193 | Some constructs are visible to `break' exit-statements and others | |
194 | are not. Which constructs are visible depends on the language. | |
195 | Therefore, the data structure allows each construct to be visible | |
196 | or not, according to the args given when the construct is started. | |
197 | The construct is visible if the `exit_label' field is non-null. | |
198 | In that case, the value should be a CODE_LABEL rtx. */ | |
199 | ||
200 | struct nesting | |
201 | { | |
202 | struct nesting *all; | |
203 | struct nesting *next; | |
204 | int depth; | |
205 | rtx exit_label; | |
206 | union | |
207 | { | |
208 | /* For conds (if-then and if-then-else statements). */ | |
209 | struct | |
210 | { | |
211 | /* Label for the end of the if construct. | |
212 | There is none if EXITFLAG was not set | |
213 | and no `else' has been seen yet. */ | |
214 | rtx endif_label; | |
215 | /* Label for the end of this alternative. | |
0f41302f | 216 | This may be the end of the if or the next else/elseif. */ |
28d81abb RK |
217 | rtx next_label; |
218 | } cond; | |
219 | /* For loops. */ | |
220 | struct | |
221 | { | |
222 | /* Label at the top of the loop; place to loop back to. */ | |
223 | rtx start_label; | |
224 | /* Label at the end of the whole construct. */ | |
225 | rtx end_label; | |
8afad312 JW |
226 | /* Label before a jump that branches to the end of the whole |
227 | construct. This is where destructors go if any. */ | |
228 | rtx alt_end_label; | |
28d81abb RK |
229 | /* Label for `continue' statement to jump to; |
230 | this is in front of the stepper of the loop. */ | |
231 | rtx continue_label; | |
232 | } loop; | |
233 | /* For variable binding contours. */ | |
234 | struct | |
235 | { | |
236 | /* Sequence number of this binding contour within the function, | |
237 | in order of entry. */ | |
238 | int block_start_count; | |
b93a436e | 239 | /* Nonzero => value to restore stack to on exit. */ |
28d81abb RK |
240 | rtx stack_level; |
241 | /* The NOTE that starts this contour. | |
242 | Used by expand_goto to check whether the destination | |
243 | is within each contour or not. */ | |
244 | rtx first_insn; | |
245 | /* Innermost containing binding contour that has a stack level. */ | |
246 | struct nesting *innermost_stack_block; | |
247 | /* List of cleanups to be run on exit from this contour. | |
248 | This is a list of expressions to be evaluated. | |
249 | The TREE_PURPOSE of each link is the ..._DECL node | |
250 | which the cleanup pertains to. */ | |
251 | tree cleanups; | |
252 | /* List of cleanup-lists of blocks containing this block, | |
253 | as they were at the locus where this block appears. | |
254 | There is an element for each containing block, | |
255 | ordered innermost containing block first. | |
e976b8b2 | 256 | The tail of this list can be 0, |
28d81abb RK |
257 | if all remaining elements would be empty lists. |
258 | The element's TREE_VALUE is the cleanup-list of that block, | |
259 | which may be null. */ | |
260 | tree outer_cleanups; | |
261 | /* Chain of labels defined inside this binding contour. | |
262 | For contours that have stack levels or cleanups. */ | |
263 | struct label_chain *label_chain; | |
264 | /* Number of function calls seen, as of start of this block. */ | |
265 | int function_call_count; | |
e976b8b2 MS |
266 | /* Nonzero if this is associated with a EH region. */ |
267 | int exception_region; | |
268 | /* The saved target_temp_slot_level from our outer block. | |
269 | We may reset target_temp_slot_level to be the level of | |
270 | this block, if that is done, target_temp_slot_level | |
271 | reverts to the saved target_temp_slot_level at the very | |
272 | end of the block. */ | |
273 | int target_temp_slot_level; | |
274 | /* True if we are currently emitting insns in an area of | |
275 | output code that is controlled by a conditional | |
276 | expression. This is used by the cleanup handling code to | |
277 | generate conditional cleanup actions. */ | |
278 | int conditional_code; | |
279 | /* A place to move the start of the exception region for any | |
280 | of the conditional cleanups, must be at the end or after | |
281 | the start of the last unconditional cleanup, and before any | |
282 | conditional branch points. */ | |
283 | rtx last_unconditional_cleanup; | |
284 | /* When in a conditional context, this is the specific | |
285 | cleanup list associated with last_unconditional_cleanup, | |
286 | where we place the conditionalized cleanups. */ | |
287 | tree *cleanup_ptr; | |
28d81abb RK |
288 | } block; |
289 | /* For switch (C) or case (Pascal) statements, | |
290 | and also for dummies (see `expand_start_case_dummy'). */ | |
291 | struct | |
292 | { | |
293 | /* The insn after which the case dispatch should finally | |
294 | be emitted. Zero for a dummy. */ | |
295 | rtx start; | |
57641239 RK |
296 | /* A list of case labels; it is first built as an AVL tree. |
297 | During expand_end_case, this is converted to a list, and may be | |
298 | rearranged into a nearly balanced binary tree. */ | |
28d81abb RK |
299 | struct case_node *case_list; |
300 | /* Label to jump to if no case matches. */ | |
301 | tree default_label; | |
302 | /* The expression to be dispatched on. */ | |
303 | tree index_expr; | |
304 | /* Type that INDEX_EXPR should be converted to. */ | |
305 | tree nominal_type; | |
306 | /* Number of range exprs in case statement. */ | |
307 | int num_ranges; | |
308 | /* Name of this kind of statement, for warnings. */ | |
309 | char *printname; | |
a11759a3 JR |
310 | /* Used to save no_line_numbers till we see the first case label. |
311 | We set this to -1 when we see the first case label in this | |
312 | case statement. */ | |
313 | int line_number_status; | |
28d81abb | 314 | } case_stmt; |
28d81abb RK |
315 | } data; |
316 | }; | |
317 | ||
318 | /* Chain of all pending binding contours. */ | |
319 | struct nesting *block_stack; | |
320 | ||
6ed1d6c5 RS |
321 | /* If any new stacks are added here, add them to POPSTACKS too. */ |
322 | ||
28d81abb RK |
323 | /* Chain of all pending binding contours that restore stack levels |
324 | or have cleanups. */ | |
325 | struct nesting *stack_block_stack; | |
326 | ||
327 | /* Chain of all pending conditional statements. */ | |
328 | struct nesting *cond_stack; | |
329 | ||
330 | /* Chain of all pending loops. */ | |
331 | struct nesting *loop_stack; | |
332 | ||
333 | /* Chain of all pending case or switch statements. */ | |
334 | struct nesting *case_stack; | |
335 | ||
28d81abb RK |
336 | /* Separate chain including all of the above, |
337 | chained through the `all' field. */ | |
338 | struct nesting *nesting_stack; | |
339 | ||
340 | /* Number of entries on nesting_stack now. */ | |
341 | int nesting_depth; | |
342 | ||
343 | /* Allocate and return a new `struct nesting'. */ | |
344 | ||
345 | #define ALLOC_NESTING() \ | |
346 | (struct nesting *) obstack_alloc (&stmt_obstack, sizeof (struct nesting)) | |
347 | ||
6ed1d6c5 RS |
348 | /* Pop the nesting stack element by element until we pop off |
349 | the element which is at the top of STACK. | |
350 | Update all the other stacks, popping off elements from them | |
351 | as we pop them from nesting_stack. */ | |
28d81abb RK |
352 | |
353 | #define POPSTACK(STACK) \ | |
6ed1d6c5 RS |
354 | do { struct nesting *target = STACK; \ |
355 | struct nesting *this; \ | |
356 | do { this = nesting_stack; \ | |
357 | if (loop_stack == this) \ | |
358 | loop_stack = loop_stack->next; \ | |
359 | if (cond_stack == this) \ | |
360 | cond_stack = cond_stack->next; \ | |
361 | if (block_stack == this) \ | |
362 | block_stack = block_stack->next; \ | |
363 | if (stack_block_stack == this) \ | |
364 | stack_block_stack = stack_block_stack->next; \ | |
365 | if (case_stack == this) \ | |
366 | case_stack = case_stack->next; \ | |
6ed1d6c5 | 367 | nesting_depth = nesting_stack->depth - 1; \ |
28d81abb | 368 | nesting_stack = this->all; \ |
28d81abb | 369 | obstack_free (&stmt_obstack, this); } \ |
6ed1d6c5 | 370 | while (this != target); } while (0) |
28d81abb RK |
371 | \f |
372 | /* In some cases it is impossible to generate code for a forward goto | |
373 | until the label definition is seen. This happens when it may be necessary | |
374 | for the goto to reset the stack pointer: we don't yet know how to do that. | |
375 | So expand_goto puts an entry on this fixup list. | |
376 | Each time a binding contour that resets the stack is exited, | |
377 | we check each fixup. | |
378 | If the target label has now been defined, we can insert the proper code. */ | |
379 | ||
380 | struct goto_fixup | |
381 | { | |
382 | /* Points to following fixup. */ | |
383 | struct goto_fixup *next; | |
384 | /* Points to the insn before the jump insn. | |
385 | If more code must be inserted, it goes after this insn. */ | |
386 | rtx before_jump; | |
387 | /* The LABEL_DECL that this jump is jumping to, or 0 | |
388 | for break, continue or return. */ | |
389 | tree target; | |
7629c936 RS |
390 | /* The BLOCK for the place where this goto was found. */ |
391 | tree context; | |
28d81abb RK |
392 | /* The CODE_LABEL rtx that this is jumping to. */ |
393 | rtx target_rtl; | |
394 | /* Number of binding contours started in current function | |
395 | before the label reference. */ | |
396 | int block_start_count; | |
397 | /* The outermost stack level that should be restored for this jump. | |
398 | Each time a binding contour that resets the stack is exited, | |
399 | if the target label is *not* yet defined, this slot is updated. */ | |
400 | rtx stack_level; | |
401 | /* List of lists of cleanup expressions to be run by this goto. | |
402 | There is one element for each block that this goto is within. | |
e976b8b2 | 403 | The tail of this list can be 0, |
28d81abb RK |
404 | if all remaining elements would be empty. |
405 | The TREE_VALUE contains the cleanup list of that block as of the | |
406 | time this goto was seen. | |
407 | The TREE_ADDRESSABLE flag is 1 for a block that has been exited. */ | |
408 | tree cleanup_list_list; | |
409 | }; | |
410 | ||
411 | static struct goto_fixup *goto_fixup_chain; | |
412 | ||
413 | /* Within any binding contour that must restore a stack level, | |
414 | all labels are recorded with a chain of these structures. */ | |
415 | ||
416 | struct label_chain | |
417 | { | |
418 | /* Points to following fixup. */ | |
419 | struct label_chain *next; | |
420 | tree label; | |
421 | }; | |
e9a25f70 JL |
422 | |
423 | ||
424 | /* Non-zero if we are using EH to handle cleanus. */ | |
425 | static int using_eh_for_cleanups_p = 0; | |
426 | ||
427 | ||
2a230e9d | 428 | static int n_occurrences PROTO((int, char *)); |
cfc3d13f | 429 | static void expand_goto_internal PROTO((tree, rtx, rtx)); |
cfc3d13f | 430 | static int expand_fixup PROTO((tree, rtx, rtx)); |
ba716ac9 BS |
431 | static void expand_nl_handler_label PROTO((rtx, rtx)); |
432 | static void expand_nl_goto_receiver PROTO((void)); | |
433 | static void expand_nl_goto_receivers PROTO((struct nesting *)); | |
cfc3d13f RK |
434 | static void fixup_gotos PROTO((struct nesting *, rtx, tree, |
435 | rtx, int)); | |
cfc3d13f | 436 | static void expand_null_return_1 PROTO((rtx, int)); |
8d800403 | 437 | static void expand_value_return PROTO((rtx)); |
cfc3d13f | 438 | static int tail_recursion_args PROTO((tree, tree)); |
50d1b7a1 | 439 | static void expand_cleanups PROTO((tree, tree, int, int)); |
0e05e8ea | 440 | static void check_seenlabel PROTO((void)); |
cfc3d13f RK |
441 | static void do_jump_if_equal PROTO((rtx, rtx, rtx, int)); |
442 | static int estimate_case_costs PROTO((case_node_ptr)); | |
443 | static void group_case_nodes PROTO((case_node_ptr)); | |
444 | static void balance_case_nodes PROTO((case_node_ptr *, | |
445 | case_node_ptr)); | |
446 | static int node_has_low_bound PROTO((case_node_ptr, tree)); | |
447 | static int node_has_high_bound PROTO((case_node_ptr, tree)); | |
448 | static int node_is_bounded PROTO((case_node_ptr, tree)); | |
449 | static void emit_jump_if_reachable PROTO((rtx)); | |
450 | static void emit_case_nodes PROTO((rtx, case_node_ptr, rtx, tree)); | |
57641239 RK |
451 | static int add_case_node PROTO((tree, tree, tree, tree *)); |
452 | static struct case_node *case_tree2list PROTO((case_node *, case_node *)); | |
28d81abb | 453 | \f |
e9a25f70 JL |
454 | void |
455 | using_eh_for_cleanups () | |
456 | { | |
457 | using_eh_for_cleanups_p = 1; | |
458 | } | |
459 | ||
28d81abb RK |
460 | void |
461 | init_stmt () | |
462 | { | |
463 | gcc_obstack_init (&stmt_obstack); | |
6adb4e3a | 464 | init_eh (); |
28d81abb RK |
465 | } |
466 | ||
467 | void | |
468 | init_stmt_for_function () | |
469 | { | |
470 | /* We are not currently within any block, conditional, loop or case. */ | |
471 | block_stack = 0; | |
0b931590 | 472 | stack_block_stack = 0; |
28d81abb RK |
473 | loop_stack = 0; |
474 | case_stack = 0; | |
475 | cond_stack = 0; | |
476 | nesting_stack = 0; | |
477 | nesting_depth = 0; | |
478 | ||
479 | block_start_count = 0; | |
480 | ||
481 | /* No gotos have been expanded yet. */ | |
482 | goto_fixup_chain = 0; | |
483 | ||
484 | /* We are not processing a ({...}) grouping. */ | |
485 | expr_stmts_for_value = 0; | |
486 | last_expr_type = 0; | |
6adb4e3a MS |
487 | |
488 | init_eh_for_function (); | |
28d81abb RK |
489 | } |
490 | ||
491 | void | |
492 | save_stmt_status (p) | |
493 | struct function *p; | |
494 | { | |
495 | p->block_stack = block_stack; | |
496 | p->stack_block_stack = stack_block_stack; | |
497 | p->cond_stack = cond_stack; | |
498 | p->loop_stack = loop_stack; | |
499 | p->case_stack = case_stack; | |
500 | p->nesting_stack = nesting_stack; | |
501 | p->nesting_depth = nesting_depth; | |
502 | p->block_start_count = block_start_count; | |
503 | p->last_expr_type = last_expr_type; | |
504 | p->last_expr_value = last_expr_value; | |
505 | p->expr_stmts_for_value = expr_stmts_for_value; | |
506 | p->emit_filename = emit_filename; | |
507 | p->emit_lineno = emit_lineno; | |
508 | p->goto_fixup_chain = goto_fixup_chain; | |
6adb4e3a | 509 | save_eh_status (p); |
28d81abb RK |
510 | } |
511 | ||
512 | void | |
513 | restore_stmt_status (p) | |
514 | struct function *p; | |
515 | { | |
516 | block_stack = p->block_stack; | |
517 | stack_block_stack = p->stack_block_stack; | |
518 | cond_stack = p->cond_stack; | |
519 | loop_stack = p->loop_stack; | |
520 | case_stack = p->case_stack; | |
521 | nesting_stack = p->nesting_stack; | |
522 | nesting_depth = p->nesting_depth; | |
523 | block_start_count = p->block_start_count; | |
524 | last_expr_type = p->last_expr_type; | |
525 | last_expr_value = p->last_expr_value; | |
526 | expr_stmts_for_value = p->expr_stmts_for_value; | |
527 | emit_filename = p->emit_filename; | |
528 | emit_lineno = p->emit_lineno; | |
529 | goto_fixup_chain = p->goto_fixup_chain; | |
6adb4e3a | 530 | restore_eh_status (p); |
28d81abb RK |
531 | } |
532 | \f | |
533 | /* Emit a no-op instruction. */ | |
534 | ||
535 | void | |
536 | emit_nop () | |
537 | { | |
ca695ac9 JB |
538 | rtx last_insn; |
539 | ||
b93a436e JL |
540 | last_insn = get_last_insn (); |
541 | if (!optimize | |
542 | && (GET_CODE (last_insn) == CODE_LABEL | |
543 | || (GET_CODE (last_insn) == NOTE | |
544 | && prev_real_insn (last_insn) == 0))) | |
545 | emit_insn (gen_nop ()); | |
28d81abb RK |
546 | } |
547 | \f | |
548 | /* Return the rtx-label that corresponds to a LABEL_DECL, | |
549 | creating it if necessary. */ | |
550 | ||
551 | rtx | |
552 | label_rtx (label) | |
553 | tree label; | |
554 | { | |
555 | if (TREE_CODE (label) != LABEL_DECL) | |
556 | abort (); | |
557 | ||
558 | if (DECL_RTL (label)) | |
559 | return DECL_RTL (label); | |
560 | ||
561 | return DECL_RTL (label) = gen_label_rtx (); | |
562 | } | |
563 | ||
564 | /* Add an unconditional jump to LABEL as the next sequential instruction. */ | |
565 | ||
566 | void | |
567 | emit_jump (label) | |
568 | rtx label; | |
569 | { | |
570 | do_pending_stack_adjust (); | |
571 | emit_jump_insn (gen_jump (label)); | |
572 | emit_barrier (); | |
573 | } | |
574 | ||
575 | /* Emit code to jump to the address | |
576 | specified by the pointer expression EXP. */ | |
577 | ||
578 | void | |
579 | expand_computed_goto (exp) | |
580 | tree exp; | |
581 | { | |
b93a436e | 582 | rtx x = expand_expr (exp, NULL_RTX, VOIDmode, 0); |
ed9a9db1 RK |
583 | |
584 | #ifdef POINTERS_EXTEND_UNSIGNED | |
b93a436e | 585 | x = convert_memory_address (Pmode, x); |
ed9a9db1 | 586 | #endif |
ffa1a1ce | 587 | |
b93a436e JL |
588 | emit_queue (); |
589 | /* Be sure the function is executable. */ | |
7d384cc0 | 590 | if (current_function_check_memory_usage) |
b93a436e JL |
591 | emit_library_call (chkr_check_exec_libfunc, 1, |
592 | VOIDmode, 1, x, ptr_mode); | |
17f5f329 | 593 | |
b93a436e JL |
594 | do_pending_stack_adjust (); |
595 | emit_indirect_jump (x); | |
acd693d1 RH |
596 | |
597 | current_function_has_computed_jump = 1; | |
28d81abb RK |
598 | } |
599 | \f | |
600 | /* Handle goto statements and the labels that they can go to. */ | |
601 | ||
602 | /* Specify the location in the RTL code of a label LABEL, | |
603 | which is a LABEL_DECL tree node. | |
604 | ||
605 | This is used for the kind of label that the user can jump to with a | |
606 | goto statement, and for alternatives of a switch or case statement. | |
607 | RTL labels generated for loops and conditionals don't go through here; | |
608 | they are generated directly at the RTL level, by other functions below. | |
609 | ||
610 | Note that this has nothing to do with defining label *names*. | |
611 | Languages vary in how they do that and what that even means. */ | |
612 | ||
613 | void | |
614 | expand_label (label) | |
615 | tree label; | |
616 | { | |
617 | struct label_chain *p; | |
618 | ||
619 | do_pending_stack_adjust (); | |
620 | emit_label (label_rtx (label)); | |
621 | if (DECL_NAME (label)) | |
622 | LABEL_NAME (DECL_RTL (label)) = IDENTIFIER_POINTER (DECL_NAME (label)); | |
623 | ||
624 | if (stack_block_stack != 0) | |
625 | { | |
626 | p = (struct label_chain *) oballoc (sizeof (struct label_chain)); | |
627 | p->next = stack_block_stack->data.block.label_chain; | |
628 | stack_block_stack->data.block.label_chain = p; | |
629 | p->label = label; | |
630 | } | |
631 | } | |
632 | ||
633 | /* Declare that LABEL (a LABEL_DECL) may be used for nonlocal gotos | |
634 | from nested functions. */ | |
635 | ||
636 | void | |
637 | declare_nonlocal_label (label) | |
638 | tree label; | |
639 | { | |
ba716ac9 BS |
640 | rtx slot = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0); |
641 | ||
28d81abb RK |
642 | nonlocal_labels = tree_cons (NULL_TREE, label, nonlocal_labels); |
643 | LABEL_PRESERVE_P (label_rtx (label)) = 1; | |
ba716ac9 | 644 | if (nonlocal_goto_handler_slots == 0) |
28d81abb | 645 | { |
59257ff7 RK |
646 | emit_stack_save (SAVE_NONLOCAL, |
647 | &nonlocal_goto_stack_level, | |
648 | PREV_INSN (tail_recursion_reentry)); | |
28d81abb | 649 | } |
ba716ac9 BS |
650 | nonlocal_goto_handler_slots |
651 | = gen_rtx_EXPR_LIST (VOIDmode, slot, nonlocal_goto_handler_slots); | |
28d81abb RK |
652 | } |
653 | ||
654 | /* Generate RTL code for a `goto' statement with target label LABEL. | |
655 | LABEL should be a LABEL_DECL tree node that was or will later be | |
656 | defined with `expand_label'. */ | |
657 | ||
658 | void | |
659 | expand_goto (label) | |
660 | tree label; | |
661 | { | |
ca695ac9 JB |
662 | tree context; |
663 | ||
28d81abb | 664 | /* Check for a nonlocal goto to a containing function. */ |
ca695ac9 | 665 | context = decl_function_context (label); |
28d81abb RK |
666 | if (context != 0 && context != current_function_decl) |
667 | { | |
668 | struct function *p = find_function_data (context); | |
38a448ca | 669 | rtx label_ref = gen_rtx_LABEL_REF (Pmode, label_rtx (label)); |
ba716ac9 BS |
670 | rtx temp, handler_slot; |
671 | tree link; | |
672 | ||
673 | /* Find the corresponding handler slot for this label. */ | |
674 | handler_slot = p->nonlocal_goto_handler_slots; | |
675 | for (link = p->nonlocal_labels; TREE_VALUE (link) != label; | |
676 | link = TREE_CHAIN (link)) | |
677 | handler_slot = XEXP (handler_slot, 1); | |
678 | handler_slot = XEXP (handler_slot, 0); | |
dd132134 | 679 | |
28d81abb | 680 | p->has_nonlocal_label = 1; |
c1255328 | 681 | current_function_has_nonlocal_goto = 1; |
dd132134 | 682 | LABEL_REF_NONLOCAL_P (label_ref) = 1; |
59257ff7 RK |
683 | |
684 | /* Copy the rtl for the slots so that they won't be shared in | |
685 | case the virtual stack vars register gets instantiated differently | |
686 | in the parent than in the child. */ | |
687 | ||
28d81abb RK |
688 | #if HAVE_nonlocal_goto |
689 | if (HAVE_nonlocal_goto) | |
690 | emit_insn (gen_nonlocal_goto (lookup_static_chain (label), | |
ba716ac9 | 691 | copy_rtx (handler_slot), |
59257ff7 | 692 | copy_rtx (p->nonlocal_goto_stack_level), |
dd132134 | 693 | label_ref)); |
28d81abb RK |
694 | else |
695 | #endif | |
696 | { | |
59257ff7 RK |
697 | rtx addr; |
698 | ||
28d81abb RK |
699 | /* Restore frame pointer for containing function. |
700 | This sets the actual hard register used for the frame pointer | |
701 | to the location of the function's incoming static chain info. | |
702 | The non-local goto handler will then adjust it to contain the | |
703 | proper value and reload the argument pointer, if needed. */ | |
a35ad168 | 704 | emit_move_insn (hard_frame_pointer_rtx, lookup_static_chain (label)); |
59257ff7 RK |
705 | |
706 | /* We have now loaded the frame pointer hardware register with | |
707 | the address of that corresponds to the start of the virtual | |
708 | stack vars. So replace virtual_stack_vars_rtx in all | |
709 | addresses we use with stack_pointer_rtx. */ | |
710 | ||
28d81abb RK |
711 | /* Get addr of containing function's current nonlocal goto handler, |
712 | which will do any cleanups and then jump to the label. */ | |
ba716ac9 | 713 | addr = copy_rtx (handler_slot); |
59257ff7 | 714 | temp = copy_to_reg (replace_rtx (addr, virtual_stack_vars_rtx, |
a35ad168 | 715 | hard_frame_pointer_rtx)); |
59257ff7 | 716 | |
28d81abb | 717 | /* Restore the stack pointer. Note this uses fp just restored. */ |
59257ff7 RK |
718 | addr = p->nonlocal_goto_stack_level; |
719 | if (addr) | |
5e116627 | 720 | addr = replace_rtx (copy_rtx (addr), |
a35ad168 DE |
721 | virtual_stack_vars_rtx, |
722 | hard_frame_pointer_rtx); | |
59257ff7 | 723 | |
37366632 | 724 | emit_stack_restore (SAVE_NONLOCAL, addr, NULL_RTX); |
59257ff7 | 725 | |
a35ad168 | 726 | /* USE of hard_frame_pointer_rtx added for consistency; not clear if |
28d81abb | 727 | really needed. */ |
38a448ca RH |
728 | emit_insn (gen_rtx_USE (VOIDmode, hard_frame_pointer_rtx)); |
729 | emit_insn (gen_rtx_USE (VOIDmode, stack_pointer_rtx)); | |
28d81abb RK |
730 | emit_indirect_jump (temp); |
731 | } | |
732 | } | |
733 | else | |
37366632 | 734 | expand_goto_internal (label, label_rtx (label), NULL_RTX); |
28d81abb RK |
735 | } |
736 | ||
737 | /* Generate RTL code for a `goto' statement with target label BODY. | |
738 | LABEL should be a LABEL_REF. | |
739 | LAST_INSN, if non-0, is the rtx we should consider as the last | |
740 | insn emitted (for the purposes of cleaning up a return). */ | |
741 | ||
742 | static void | |
743 | expand_goto_internal (body, label, last_insn) | |
744 | tree body; | |
745 | rtx label; | |
746 | rtx last_insn; | |
747 | { | |
748 | struct nesting *block; | |
749 | rtx stack_level = 0; | |
750 | ||
751 | if (GET_CODE (label) != CODE_LABEL) | |
752 | abort (); | |
753 | ||
754 | /* If label has already been defined, we can tell now | |
755 | whether and how we must alter the stack level. */ | |
756 | ||
757 | if (PREV_INSN (label) != 0) | |
758 | { | |
759 | /* Find the innermost pending block that contains the label. | |
760 | (Check containment by comparing insn-uids.) | |
761 | Then restore the outermost stack level within that block, | |
762 | and do cleanups of all blocks contained in it. */ | |
763 | for (block = block_stack; block; block = block->next) | |
764 | { | |
765 | if (INSN_UID (block->data.block.first_insn) < INSN_UID (label)) | |
766 | break; | |
767 | if (block->data.block.stack_level != 0) | |
768 | stack_level = block->data.block.stack_level; | |
769 | /* Execute the cleanups for blocks we are exiting. */ | |
770 | if (block->data.block.cleanups != 0) | |
771 | { | |
50d1b7a1 | 772 | expand_cleanups (block->data.block.cleanups, NULL_TREE, 1, 1); |
28d81abb RK |
773 | do_pending_stack_adjust (); |
774 | } | |
775 | } | |
776 | ||
777 | if (stack_level) | |
778 | { | |
0f41302f MS |
779 | /* Ensure stack adjust isn't done by emit_jump, as this |
780 | would clobber the stack pointer. This one should be | |
781 | deleted as dead by flow. */ | |
28d81abb RK |
782 | clear_pending_stack_adjust (); |
783 | do_pending_stack_adjust (); | |
37366632 | 784 | emit_stack_restore (SAVE_BLOCK, stack_level, NULL_RTX); |
28d81abb RK |
785 | } |
786 | ||
787 | if (body != 0 && DECL_TOO_LATE (body)) | |
788 | error ("jump to `%s' invalidly jumps into binding contour", | |
789 | IDENTIFIER_POINTER (DECL_NAME (body))); | |
790 | } | |
791 | /* Label not yet defined: may need to put this goto | |
792 | on the fixup list. */ | |
793 | else if (! expand_fixup (body, label, last_insn)) | |
794 | { | |
795 | /* No fixup needed. Record that the label is the target | |
796 | of at least one goto that has no fixup. */ | |
797 | if (body != 0) | |
798 | TREE_ADDRESSABLE (body) = 1; | |
799 | } | |
800 | ||
801 | emit_jump (label); | |
802 | } | |
803 | \f | |
804 | /* Generate if necessary a fixup for a goto | |
805 | whose target label in tree structure (if any) is TREE_LABEL | |
806 | and whose target in rtl is RTL_LABEL. | |
807 | ||
808 | If LAST_INSN is nonzero, we pretend that the jump appears | |
809 | after insn LAST_INSN instead of at the current point in the insn stream. | |
810 | ||
023b57e6 RS |
811 | The fixup will be used later to insert insns just before the goto. |
812 | Those insns will restore the stack level as appropriate for the | |
813 | target label, and will (in the case of C++) also invoke any object | |
814 | destructors which have to be invoked when we exit the scopes which | |
815 | are exited by the goto. | |
28d81abb RK |
816 | |
817 | Value is nonzero if a fixup is made. */ | |
818 | ||
819 | static int | |
820 | expand_fixup (tree_label, rtl_label, last_insn) | |
821 | tree tree_label; | |
822 | rtx rtl_label; | |
823 | rtx last_insn; | |
824 | { | |
825 | struct nesting *block, *end_block; | |
826 | ||
827 | /* See if we can recognize which block the label will be output in. | |
828 | This is possible in some very common cases. | |
829 | If we succeed, set END_BLOCK to that block. | |
830 | Otherwise, set it to 0. */ | |
831 | ||
832 | if (cond_stack | |
833 | && (rtl_label == cond_stack->data.cond.endif_label | |
834 | || rtl_label == cond_stack->data.cond.next_label)) | |
835 | end_block = cond_stack; | |
836 | /* If we are in a loop, recognize certain labels which | |
837 | are likely targets. This reduces the number of fixups | |
838 | we need to create. */ | |
839 | else if (loop_stack | |
840 | && (rtl_label == loop_stack->data.loop.start_label | |
841 | || rtl_label == loop_stack->data.loop.end_label | |
842 | || rtl_label == loop_stack->data.loop.continue_label)) | |
843 | end_block = loop_stack; | |
844 | else | |
845 | end_block = 0; | |
846 | ||
847 | /* Now set END_BLOCK to the binding level to which we will return. */ | |
848 | ||
849 | if (end_block) | |
850 | { | |
851 | struct nesting *next_block = end_block->all; | |
852 | block = block_stack; | |
853 | ||
854 | /* First see if the END_BLOCK is inside the innermost binding level. | |
855 | If so, then no cleanups or stack levels are relevant. */ | |
856 | while (next_block && next_block != block) | |
857 | next_block = next_block->all; | |
858 | ||
859 | if (next_block) | |
860 | return 0; | |
861 | ||
862 | /* Otherwise, set END_BLOCK to the innermost binding level | |
863 | which is outside the relevant control-structure nesting. */ | |
864 | next_block = block_stack->next; | |
865 | for (block = block_stack; block != end_block; block = block->all) | |
866 | if (block == next_block) | |
867 | next_block = next_block->next; | |
868 | end_block = next_block; | |
869 | } | |
870 | ||
871 | /* Does any containing block have a stack level or cleanups? | |
872 | If not, no fixup is needed, and that is the normal case | |
873 | (the only case, for standard C). */ | |
874 | for (block = block_stack; block != end_block; block = block->next) | |
875 | if (block->data.block.stack_level != 0 | |
876 | || block->data.block.cleanups != 0) | |
877 | break; | |
878 | ||
879 | if (block != end_block) | |
880 | { | |
881 | /* Ok, a fixup is needed. Add a fixup to the list of such. */ | |
882 | struct goto_fixup *fixup | |
883 | = (struct goto_fixup *) oballoc (sizeof (struct goto_fixup)); | |
884 | /* In case an old stack level is restored, make sure that comes | |
885 | after any pending stack adjust. */ | |
886 | /* ?? If the fixup isn't to come at the present position, | |
887 | doing the stack adjust here isn't useful. Doing it with our | |
888 | settings at that location isn't useful either. Let's hope | |
889 | someone does it! */ | |
890 | if (last_insn == 0) | |
891 | do_pending_stack_adjust (); | |
28d81abb RK |
892 | fixup->target = tree_label; |
893 | fixup->target_rtl = rtl_label; | |
023b57e6 RS |
894 | |
895 | /* Create a BLOCK node and a corresponding matched set of | |
896 | NOTE_INSN_BEGIN_BLOCK and NOTE_INSN_END_BLOCK notes at | |
897 | this point. The notes will encapsulate any and all fixup | |
898 | code which we might later insert at this point in the insn | |
899 | stream. Also, the BLOCK node will be the parent (i.e. the | |
900 | `SUPERBLOCK') of any other BLOCK nodes which we might create | |
0679e3fc JM |
901 | later on when we are expanding the fixup code. |
902 | ||
903 | Note that optimization passes (including expand_end_loop) | |
904 | might move the *_BLOCK notes away, so we use a NOTE_INSN_DELETED | |
905 | as a placeholder. */ | |
023b57e6 RS |
906 | |
907 | { | |
908 | register rtx original_before_jump | |
909 | = last_insn ? last_insn : get_last_insn (); | |
0679e3fc | 910 | rtx start; |
023b57e6 RS |
911 | |
912 | start_sequence (); | |
913 | pushlevel (0); | |
0679e3fc JM |
914 | start = emit_note (NULL_PTR, NOTE_INSN_BLOCK_BEG); |
915 | fixup->before_jump = emit_note (NULL_PTR, NOTE_INSN_DELETED); | |
023b57e6 RS |
916 | last_block_end_note = emit_note (NULL_PTR, NOTE_INSN_BLOCK_END); |
917 | fixup->context = poplevel (1, 0, 0); /* Create the BLOCK node now! */ | |
918 | end_sequence (); | |
0679e3fc | 919 | emit_insns_after (start, original_before_jump); |
023b57e6 RS |
920 | } |
921 | ||
28d81abb RK |
922 | fixup->block_start_count = block_start_count; |
923 | fixup->stack_level = 0; | |
924 | fixup->cleanup_list_list | |
e976b8b2 | 925 | = ((block->data.block.outer_cleanups |
28d81abb | 926 | || block->data.block.cleanups) |
37366632 | 927 | ? tree_cons (NULL_TREE, block->data.block.cleanups, |
28d81abb RK |
928 | block->data.block.outer_cleanups) |
929 | : 0); | |
930 | fixup->next = goto_fixup_chain; | |
931 | goto_fixup_chain = fixup; | |
932 | } | |
933 | ||
934 | return block != 0; | |
935 | } | |
936 | ||
ca695ac9 | 937 | |
cfc3d13f RK |
938 | \f |
939 | /* Expand any needed fixups in the outputmost binding level of the | |
940 | function. FIRST_INSN is the first insn in the function. */ | |
ca695ac9 | 941 | |
cfc3d13f RK |
942 | void |
943 | expand_fixups (first_insn) | |
944 | rtx first_insn; | |
945 | { | |
946 | fixup_gotos (NULL_PTR, NULL_RTX, NULL_TREE, first_insn, 0); | |
947 | } | |
ca695ac9 | 948 | |
28d81abb RK |
949 | /* When exiting a binding contour, process all pending gotos requiring fixups. |
950 | THISBLOCK is the structure that describes the block being exited. | |
951 | STACK_LEVEL is the rtx for the stack level to restore exiting this contour. | |
952 | CLEANUP_LIST is a list of expressions to evaluate on exiting this contour. | |
953 | FIRST_INSN is the insn that began this contour. | |
954 | ||
955 | Gotos that jump out of this contour must restore the | |
956 | stack level and do the cleanups before actually jumping. | |
957 | ||
958 | DONT_JUMP_IN nonzero means report error there is a jump into this | |
959 | contour from before the beginning of the contour. | |
960 | This is also done if STACK_LEVEL is nonzero. */ | |
961 | ||
704f4dca | 962 | static void |
28d81abb RK |
963 | fixup_gotos (thisblock, stack_level, cleanup_list, first_insn, dont_jump_in) |
964 | struct nesting *thisblock; | |
965 | rtx stack_level; | |
966 | tree cleanup_list; | |
967 | rtx first_insn; | |
968 | int dont_jump_in; | |
969 | { | |
970 | register struct goto_fixup *f, *prev; | |
971 | ||
972 | /* F is the fixup we are considering; PREV is the previous one. */ | |
973 | /* We run this loop in two passes so that cleanups of exited blocks | |
974 | are run first, and blocks that are exited are marked so | |
975 | afterwards. */ | |
976 | ||
977 | for (prev = 0, f = goto_fixup_chain; f; prev = f, f = f->next) | |
978 | { | |
979 | /* Test for a fixup that is inactive because it is already handled. */ | |
980 | if (f->before_jump == 0) | |
981 | { | |
982 | /* Delete inactive fixup from the chain, if that is easy to do. */ | |
983 | if (prev != 0) | |
984 | prev->next = f->next; | |
985 | } | |
986 | /* Has this fixup's target label been defined? | |
987 | If so, we can finalize it. */ | |
988 | else if (PREV_INSN (f->target_rtl) != 0) | |
989 | { | |
7629c936 | 990 | register rtx cleanup_insns; |
7629c936 | 991 | |
28d81abb RK |
992 | /* Get the first non-label after the label |
993 | this goto jumps to. If that's before this scope begins, | |
994 | we don't have a jump into the scope. */ | |
995 | rtx after_label = f->target_rtl; | |
996 | while (after_label != 0 && GET_CODE (after_label) == CODE_LABEL) | |
997 | after_label = NEXT_INSN (after_label); | |
998 | ||
999 | /* If this fixup jumped into this contour from before the beginning | |
1000 | of this contour, report an error. */ | |
1001 | /* ??? Bug: this does not detect jumping in through intermediate | |
1002 | blocks that have stack levels or cleanups. | |
1003 | It detects only a problem with the innermost block | |
1004 | around the label. */ | |
1005 | if (f->target != 0 | |
1006 | && (dont_jump_in || stack_level || cleanup_list) | |
1007 | /* If AFTER_LABEL is 0, it means the jump goes to the end | |
1008 | of the rtl, which means it jumps into this scope. */ | |
1009 | && (after_label == 0 | |
1010 | || INSN_UID (first_insn) < INSN_UID (after_label)) | |
1011 | && INSN_UID (first_insn) > INSN_UID (f->before_jump) | |
33bc3ff5 | 1012 | && ! DECL_ERROR_ISSUED (f->target)) |
28d81abb RK |
1013 | { |
1014 | error_with_decl (f->target, | |
1015 | "label `%s' used before containing binding contour"); | |
1016 | /* Prevent multiple errors for one label. */ | |
33bc3ff5 | 1017 | DECL_ERROR_ISSUED (f->target) = 1; |
28d81abb RK |
1018 | } |
1019 | ||
7629c936 RS |
1020 | /* We will expand the cleanups into a sequence of their own and |
1021 | then later on we will attach this new sequence to the insn | |
1022 | stream just ahead of the actual jump insn. */ | |
1023 | ||
1024 | start_sequence (); | |
1025 | ||
023b57e6 RS |
1026 | /* Temporarily restore the lexical context where we will |
1027 | logically be inserting the fixup code. We do this for the | |
1028 | sake of getting the debugging information right. */ | |
1029 | ||
7629c936 | 1030 | pushlevel (0); |
023b57e6 | 1031 | set_block (f->context); |
7629c936 RS |
1032 | |
1033 | /* Expand the cleanups for blocks this jump exits. */ | |
28d81abb RK |
1034 | if (f->cleanup_list_list) |
1035 | { | |
1036 | tree lists; | |
1037 | for (lists = f->cleanup_list_list; lists; lists = TREE_CHAIN (lists)) | |
1038 | /* Marked elements correspond to blocks that have been closed. | |
1039 | Do their cleanups. */ | |
1040 | if (TREE_ADDRESSABLE (lists) | |
1041 | && TREE_VALUE (lists) != 0) | |
7629c936 | 1042 | { |
50d1b7a1 | 1043 | expand_cleanups (TREE_VALUE (lists), NULL_TREE, 1, 1); |
7629c936 RS |
1044 | /* Pop any pushes done in the cleanups, |
1045 | in case function is about to return. */ | |
1046 | do_pending_stack_adjust (); | |
1047 | } | |
28d81abb RK |
1048 | } |
1049 | ||
1050 | /* Restore stack level for the biggest contour that this | |
1051 | jump jumps out of. */ | |
1052 | if (f->stack_level) | |
59257ff7 | 1053 | emit_stack_restore (SAVE_BLOCK, f->stack_level, f->before_jump); |
7629c936 RS |
1054 | |
1055 | /* Finish up the sequence containing the insns which implement the | |
1056 | necessary cleanups, and then attach that whole sequence to the | |
1057 | insn stream just ahead of the actual jump insn. Attaching it | |
1058 | at that point insures that any cleanups which are in fact | |
1059 | implicit C++ object destructions (which must be executed upon | |
1060 | leaving the block) appear (to the debugger) to be taking place | |
1061 | in an area of the generated code where the object(s) being | |
1062 | destructed are still "in scope". */ | |
1063 | ||
1064 | cleanup_insns = get_insns (); | |
023b57e6 | 1065 | poplevel (1, 0, 0); |
7629c936 RS |
1066 | |
1067 | end_sequence (); | |
1068 | emit_insns_after (cleanup_insns, f->before_jump); | |
1069 | ||
7629c936 | 1070 | |
28d81abb RK |
1071 | f->before_jump = 0; |
1072 | } | |
1073 | } | |
1074 | ||
6bc2f582 RK |
1075 | /* For any still-undefined labels, do the cleanups for this block now. |
1076 | We must do this now since items in the cleanup list may go out | |
0f41302f | 1077 | of scope when the block ends. */ |
28d81abb RK |
1078 | for (prev = 0, f = goto_fixup_chain; f; prev = f, f = f->next) |
1079 | if (f->before_jump != 0 | |
1080 | && PREV_INSN (f->target_rtl) == 0 | |
1081 | /* Label has still not appeared. If we are exiting a block with | |
1082 | a stack level to restore, that started before the fixup, | |
1083 | mark this stack level as needing restoration | |
6bc2f582 | 1084 | when the fixup is later finalized. */ |
28d81abb | 1085 | && thisblock != 0 |
6bc2f582 RK |
1086 | /* Note: if THISBLOCK == 0 and we have a label that hasn't appeared, it |
1087 | means the label is undefined. That's erroneous, but possible. */ | |
28d81abb RK |
1088 | && (thisblock->data.block.block_start_count |
1089 | <= f->block_start_count)) | |
1090 | { | |
1091 | tree lists = f->cleanup_list_list; | |
6bc2f582 RK |
1092 | rtx cleanup_insns; |
1093 | ||
28d81abb RK |
1094 | for (; lists; lists = TREE_CHAIN (lists)) |
1095 | /* If the following elt. corresponds to our containing block | |
1096 | then the elt. must be for this block. */ | |
1097 | if (TREE_CHAIN (lists) == thisblock->data.block.outer_cleanups) | |
6bc2f582 RK |
1098 | { |
1099 | start_sequence (); | |
1100 | pushlevel (0); | |
1101 | set_block (f->context); | |
1102 | expand_cleanups (TREE_VALUE (lists), NULL_TREE, 1, 1); | |
f0959e58 | 1103 | do_pending_stack_adjust (); |
6bc2f582 RK |
1104 | cleanup_insns = get_insns (); |
1105 | poplevel (1, 0, 0); | |
1106 | end_sequence (); | |
412c00dc RK |
1107 | if (cleanup_insns != 0) |
1108 | f->before_jump | |
1109 | = emit_insns_after (cleanup_insns, f->before_jump); | |
6bc2f582 | 1110 | |
e07ed33f | 1111 | f->cleanup_list_list = TREE_CHAIN (lists); |
6bc2f582 | 1112 | } |
28d81abb RK |
1113 | |
1114 | if (stack_level) | |
1115 | f->stack_level = stack_level; | |
1116 | } | |
1117 | } | |
2a230e9d BS |
1118 | \f |
1119 | /* Return the number of times character C occurs in string S. */ | |
1120 | static int | |
1121 | n_occurrences (c, s) | |
1122 | int c; | |
1123 | char *s; | |
1124 | { | |
1125 | int n = 0; | |
1126 | while (*s) | |
1127 | n += (*s++ == c); | |
1128 | return n; | |
1129 | } | |
28d81abb RK |
1130 | \f |
1131 | /* Generate RTL for an asm statement (explicit assembler code). | |
1132 | BODY is a STRING_CST node containing the assembler code text, | |
1133 | or an ADDR_EXPR containing a STRING_CST. */ | |
1134 | ||
1135 | void | |
1136 | expand_asm (body) | |
1137 | tree body; | |
1138 | { | |
7d384cc0 | 1139 | if (current_function_check_memory_usage) |
17f5f329 RK |
1140 | { |
1141 | error ("`asm' cannot be used with `-fcheck-memory-usage'"); | |
1142 | return; | |
1143 | } | |
1144 | ||
28d81abb RK |
1145 | if (TREE_CODE (body) == ADDR_EXPR) |
1146 | body = TREE_OPERAND (body, 0); | |
1147 | ||
38a448ca RH |
1148 | emit_insn (gen_rtx_ASM_INPUT (VOIDmode, |
1149 | TREE_STRING_POINTER (body))); | |
28d81abb RK |
1150 | last_expr_type = 0; |
1151 | } | |
1152 | ||
1153 | /* Generate RTL for an asm statement with arguments. | |
1154 | STRING is the instruction template. | |
1155 | OUTPUTS is a list of output arguments (lvalues); INPUTS a list of inputs. | |
1156 | Each output or input has an expression in the TREE_VALUE and | |
1157 | a constraint-string in the TREE_PURPOSE. | |
1158 | CLOBBERS is a list of STRING_CST nodes each naming a hard register | |
1159 | that is clobbered by this insn. | |
1160 | ||
1161 | Not all kinds of lvalue that may appear in OUTPUTS can be stored directly. | |
1162 | Some elements of OUTPUTS may be replaced with trees representing temporary | |
1163 | values. The caller should copy those temporary values to the originally | |
1164 | specified lvalues. | |
1165 | ||
1166 | VOL nonzero means the insn is volatile; don't optimize it. */ | |
1167 | ||
1168 | void | |
1169 | expand_asm_operands (string, outputs, inputs, clobbers, vol, filename, line) | |
1170 | tree string, outputs, inputs, clobbers; | |
1171 | int vol; | |
1172 | char *filename; | |
1173 | int line; | |
1174 | { | |
1175 | rtvec argvec, constraints; | |
1176 | rtx body; | |
1177 | int ninputs = list_length (inputs); | |
1178 | int noutputs = list_length (outputs); | |
235c5021 | 1179 | int ninout = 0; |
b4ccaa16 | 1180 | int nclobbers; |
28d81abb RK |
1181 | tree tail; |
1182 | register int i; | |
1183 | /* Vector of RTX's of evaluated output operands. */ | |
1184 | rtx *output_rtx = (rtx *) alloca (noutputs * sizeof (rtx)); | |
235c5021 RK |
1185 | int *inout_opnum = (int *) alloca (noutputs * sizeof (int)); |
1186 | enum machine_mode *inout_mode | |
1187 | = (enum machine_mode *) alloca (noutputs * sizeof (enum machine_mode)); | |
28d81abb RK |
1188 | /* The insn we have emitted. */ |
1189 | rtx insn; | |
1190 | ||
e5e809f4 | 1191 | /* An ASM with no outputs needs to be treated as volatile, for now. */ |
296f8acc JL |
1192 | if (noutputs == 0) |
1193 | vol = 1; | |
1194 | ||
7d384cc0 | 1195 | if (current_function_check_memory_usage) |
17f5f329 RK |
1196 | { |
1197 | error ("`asm' cannot be used with `-fcheck-memory-usage'"); | |
1198 | return; | |
1199 | } | |
1200 | ||
b4ccaa16 RS |
1201 | /* Count the number of meaningful clobbered registers, ignoring what |
1202 | we would ignore later. */ | |
1203 | nclobbers = 0; | |
1204 | for (tail = clobbers; tail; tail = TREE_CHAIN (tail)) | |
1205 | { | |
1206 | char *regname = TREE_STRING_POINTER (TREE_VALUE (tail)); | |
c09e6498 RS |
1207 | i = decode_reg_name (regname); |
1208 | if (i >= 0 || i == -4) | |
b4ccaa16 | 1209 | ++nclobbers; |
7859e3ac DE |
1210 | else if (i == -2) |
1211 | error ("unknown register name `%s' in `asm'", regname); | |
b4ccaa16 RS |
1212 | } |
1213 | ||
28d81abb RK |
1214 | last_expr_type = 0; |
1215 | ||
2a230e9d BS |
1216 | /* Check that the number of alternatives is constant across all |
1217 | operands. */ | |
1218 | if (outputs || inputs) | |
1219 | { | |
1220 | tree tmp = TREE_PURPOSE (outputs ? outputs : inputs); | |
1221 | int nalternatives = n_occurrences (',', TREE_STRING_POINTER (tmp)); | |
1222 | tree next = inputs; | |
1223 | ||
f62a15e3 BS |
1224 | if (nalternatives + 1 > MAX_RECOG_ALTERNATIVES) |
1225 | { | |
1226 | error ("too many alternatives in `asm'"); | |
1227 | return; | |
1228 | } | |
1229 | ||
2a230e9d BS |
1230 | tmp = outputs; |
1231 | while (tmp) | |
1232 | { | |
1233 | char *constraint = TREE_STRING_POINTER (TREE_PURPOSE (tmp)); | |
1234 | if (n_occurrences (',', constraint) != nalternatives) | |
1235 | { | |
1236 | error ("operand constraints for `asm' differ in number of alternatives"); | |
1237 | return; | |
1238 | } | |
1239 | if (TREE_CHAIN (tmp)) | |
1240 | tmp = TREE_CHAIN (tmp); | |
1241 | else | |
1242 | tmp = next, next = 0; | |
1243 | } | |
1244 | } | |
1245 | ||
28d81abb RK |
1246 | for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++) |
1247 | { | |
1248 | tree val = TREE_VALUE (tail); | |
b50a024d | 1249 | tree type = TREE_TYPE (val); |
2a230e9d | 1250 | char *constraint; |
3fbd5c2c | 1251 | char *p; |
2a230e9d | 1252 | int c_len; |
28d81abb | 1253 | int j; |
2a230e9d | 1254 | int is_inout = 0; |
d09a75ae | 1255 | int allows_reg = 0; |
1afbe1c4 | 1256 | int allows_mem = 0; |
28d81abb RK |
1257 | |
1258 | /* If there's an erroneous arg, emit no insn. */ | |
1259 | if (TREE_TYPE (val) == error_mark_node) | |
1260 | return; | |
1261 | ||
d09a75ae RK |
1262 | /* Make sure constraint has `=' and does not have `+'. Also, see |
1263 | if it allows any register. Be liberal on the latter test, since | |
1264 | the worst that happens if we get it wrong is we issue an error | |
1265 | message. */ | |
28d81abb | 1266 | |
2a230e9d BS |
1267 | c_len = TREE_STRING_LENGTH (TREE_PURPOSE (tail)) - 1; |
1268 | constraint = TREE_STRING_POINTER (TREE_PURPOSE (tail)); | |
1269 | ||
3fbd5c2c RH |
1270 | /* Allow the `=' or `+' to not be at the beginning of the string, |
1271 | since it wasn't explicitly documented that way, and there is a | |
1272 | large body of code that puts it last. Swap the character to | |
1273 | the front, so as not to uglify any place else. */ | |
1274 | switch (c_len) | |
2a230e9d | 1275 | { |
3fbd5c2c RH |
1276 | default: |
1277 | if ((p = strchr (constraint, '=')) != NULL) | |
1278 | break; | |
1279 | if ((p = strchr (constraint, '+')) != NULL) | |
1280 | break; | |
1281 | case 0: | |
2a230e9d BS |
1282 | error ("output operand constraint lacks `='"); |
1283 | return; | |
1284 | } | |
1285 | ||
3fbd5c2c RH |
1286 | if (p != constraint) |
1287 | { | |
1288 | j = *p; | |
1289 | bcopy (constraint, constraint+1, p-constraint); | |
1290 | *constraint = j; | |
1291 | ||
1292 | warning ("output constraint `%c' for operand %d is not at the beginning", j, i); | |
1293 | } | |
1294 | ||
2a230e9d BS |
1295 | is_inout = constraint[0] == '+'; |
1296 | /* Replace '+' with '='. */ | |
1297 | constraint[0] = '='; | |
1298 | /* Make sure we can specify the matching operand. */ | |
1299 | if (is_inout && i > 9) | |
1300 | { | |
1301 | error ("output operand constraint %d contains `+'", i); | |
1302 | return; | |
1303 | } | |
1304 | ||
1305 | for (j = 1; j < c_len; j++) | |
1306 | switch (constraint[j]) | |
d09a75ae RK |
1307 | { |
1308 | case '+': | |
2a230e9d BS |
1309 | case '=': |
1310 | error ("operand constraint contains '+' or '=' at illegal position."); | |
1311 | return; | |
1312 | ||
1313 | case '%': | |
1314 | if (i + 1 == ninputs + noutputs) | |
235c5021 | 1315 | { |
2a230e9d | 1316 | error ("`%%' constraint used with last operand"); |
235c5021 RK |
1317 | return; |
1318 | } | |
235c5021 | 1319 | break; |
d09a75ae | 1320 | |
2a230e9d | 1321 | case '?': case '!': case '*': case '&': |
1afbe1c4 | 1322 | case 'E': case 'F': case 'G': case 'H': |
d09a75ae RK |
1323 | case 's': case 'i': case 'n': |
1324 | case 'I': case 'J': case 'K': case 'L': case 'M': | |
1325 | case 'N': case 'O': case 'P': case ',': | |
1326 | #ifdef EXTRA_CONSTRAINT | |
1327 | case 'Q': case 'R': case 'S': case 'T': case 'U': | |
1328 | #endif | |
1329 | break; | |
1330 | ||
7b7a33b3 | 1331 | case '0': case '1': case '2': case '3': case '4': |
cd76ea33 RK |
1332 | case '5': case '6': case '7': case '8': case '9': |
1333 | error ("matching constraint not valid in output operand"); | |
1334 | break; | |
1335 | ||
1afbe1c4 RH |
1336 | case 'V': case 'm': case 'o': |
1337 | allows_mem = 1; | |
1338 | break; | |
1339 | ||
1340 | case '<': case '>': | |
1341 | /* ??? Before flow, auto inc/dec insns are not supposed to exist, | |
1342 | excepting those that expand_call created. So match memory | |
1343 | and hope. */ | |
1344 | allows_mem = 1; | |
1345 | break; | |
1346 | ||
1347 | case 'g': case 'X': | |
1348 | allows_reg = 1; | |
1349 | allows_mem = 1; | |
1350 | break; | |
1351 | ||
1352 | case 'p': case 'r': | |
d09a75ae RK |
1353 | default: |
1354 | allows_reg = 1; | |
1355 | break; | |
1356 | } | |
1357 | ||
d09a75ae RK |
1358 | /* If an output operand is not a decl or indirect ref and our constraint |
1359 | allows a register, make a temporary to act as an intermediate. | |
1360 | Make the asm insn write into that, then our caller will copy it to | |
1361 | the real output operand. Likewise for promoted variables. */ | |
28d81abb | 1362 | |
1afbe1c4 RH |
1363 | if ((TREE_CODE (val) == INDIRECT_REF |
1364 | && allows_mem) | |
b50a024d | 1365 | || (TREE_CODE_CLASS (TREE_CODE (val)) == 'd' |
1afbe1c4 | 1366 | && (allows_mem || GET_CODE (DECL_RTL (val)) == REG) |
b50a024d | 1367 | && ! (GET_CODE (DECL_RTL (val)) == REG |
d09a75ae | 1368 | && GET_MODE (DECL_RTL (val)) != TYPE_MODE (type))) |
235c5021 | 1369 | || ! allows_reg |
2a230e9d | 1370 | || is_inout) |
d09a75ae RK |
1371 | { |
1372 | if (! allows_reg) | |
1373 | mark_addressable (TREE_VALUE (tail)); | |
1374 | ||
1375 | output_rtx[i] | |
17f5f329 RK |
1376 | = expand_expr (TREE_VALUE (tail), NULL_RTX, VOIDmode, |
1377 | EXPAND_MEMORY_USE_WO); | |
d09a75ae RK |
1378 | |
1379 | if (! allows_reg && GET_CODE (output_rtx[i]) != MEM) | |
1380 | error ("output number %d not directly addressable", i); | |
1afbe1c4 RH |
1381 | if (! allows_mem && GET_CODE (output_rtx[i]) == MEM) |
1382 | error ("output number %d not restored to memory", i); | |
d09a75ae | 1383 | } |
b50a024d | 1384 | else |
e619bb8d | 1385 | { |
6e81958a | 1386 | output_rtx[i] = assign_temp (type, 0, 0, 0); |
b50a024d RK |
1387 | TREE_VALUE (tail) = make_tree (type, output_rtx[i]); |
1388 | } | |
235c5021 | 1389 | |
2a230e9d | 1390 | if (is_inout) |
235c5021 RK |
1391 | { |
1392 | inout_mode[ninout] = TYPE_MODE (TREE_TYPE (TREE_VALUE (tail))); | |
1393 | inout_opnum[ninout++] = i; | |
1394 | } | |
28d81abb RK |
1395 | } |
1396 | ||
235c5021 | 1397 | ninputs += ninout; |
28d81abb RK |
1398 | if (ninputs + noutputs > MAX_RECOG_OPERANDS) |
1399 | { | |
1400 | error ("more than %d operands in `asm'", MAX_RECOG_OPERANDS); | |
1401 | return; | |
1402 | } | |
1403 | ||
1404 | /* Make vectors for the expression-rtx and constraint strings. */ | |
1405 | ||
1406 | argvec = rtvec_alloc (ninputs); | |
1407 | constraints = rtvec_alloc (ninputs); | |
1408 | ||
38a448ca RH |
1409 | body = gen_rtx_ASM_OPERANDS (VOIDmode, |
1410 | TREE_STRING_POINTER (string), "", 0, argvec, | |
1411 | constraints, filename, line); | |
c85f7c16 | 1412 | |
78418280 | 1413 | MEM_VOLATILE_P (body) = vol; |
28d81abb RK |
1414 | |
1415 | /* Eval the inputs and put them into ARGVEC. | |
1416 | Put their constraints into ASM_INPUTs and store in CONSTRAINTS. */ | |
1417 | ||
1418 | i = 0; | |
1419 | for (tail = inputs; tail; tail = TREE_CHAIN (tail)) | |
1420 | { | |
1421 | int j; | |
1f06ee8d RH |
1422 | int allows_reg = 0, allows_mem = 0; |
1423 | char *constraint, *orig_constraint; | |
2a230e9d | 1424 | int c_len; |
1f06ee8d | 1425 | rtx op; |
28d81abb RK |
1426 | |
1427 | /* If there's an erroneous arg, emit no insn, | |
1428 | because the ASM_INPUT would get VOIDmode | |
1429 | and that could cause a crash in reload. */ | |
1430 | if (TREE_TYPE (TREE_VALUE (tail)) == error_mark_node) | |
1431 | return; | |
2a230e9d BS |
1432 | |
1433 | /* ??? Can this happen, and does the error message make any sense? */ | |
28d81abb RK |
1434 | if (TREE_PURPOSE (tail) == NULL_TREE) |
1435 | { | |
1436 | error ("hard register `%s' listed as input operand to `asm'", | |
1437 | TREE_STRING_POINTER (TREE_VALUE (tail)) ); | |
1438 | return; | |
1439 | } | |
1440 | ||
2a230e9d BS |
1441 | c_len = TREE_STRING_LENGTH (TREE_PURPOSE (tail)) - 1; |
1442 | constraint = TREE_STRING_POINTER (TREE_PURPOSE (tail)); | |
1f06ee8d | 1443 | orig_constraint = constraint; |
28d81abb | 1444 | |
2a230e9d BS |
1445 | /* Make sure constraint has neither `=', `+', nor '&'. */ |
1446 | ||
1447 | for (j = 0; j < c_len; j++) | |
1448 | switch (constraint[j]) | |
28d81abb | 1449 | { |
2a230e9d | 1450 | case '+': case '=': case '&': |
1f06ee8d RH |
1451 | if (constraint == orig_constraint) |
1452 | { | |
1453 | error ("input operand constraint contains `%c'", constraint[j]); | |
1454 | return; | |
1455 | } | |
1456 | break; | |
65fed0cb | 1457 | |
2a230e9d | 1458 | case '%': |
1f06ee8d RH |
1459 | if (constraint == orig_constraint |
1460 | && i + 1 == ninputs - ninout) | |
2a230e9d BS |
1461 | { |
1462 | error ("`%%' constraint used with last operand"); | |
1463 | return; | |
1464 | } | |
1465 | break; | |
1466 | ||
1f06ee8d RH |
1467 | case 'V': case 'm': case 'o': |
1468 | allows_mem = 1; | |
1469 | break; | |
1470 | ||
1471 | case '<': case '>': | |
2a230e9d | 1472 | case '?': case '!': case '*': |
65fed0cb RK |
1473 | case 'E': case 'F': case 'G': case 'H': case 'X': |
1474 | case 's': case 'i': case 'n': | |
1475 | case 'I': case 'J': case 'K': case 'L': case 'M': | |
1476 | case 'N': case 'O': case 'P': case ',': | |
1477 | #ifdef EXTRA_CONSTRAINT | |
1478 | case 'Q': case 'R': case 'S': case 'T': case 'U': | |
1479 | #endif | |
1480 | break; | |
1481 | ||
7b7a33b3 JW |
1482 | /* Whether or not a numeric constraint allows a register is |
1483 | decided by the matching constraint, and so there is no need | |
1484 | to do anything special with them. We must handle them in | |
1485 | the default case, so that we don't unnecessarily force | |
1486 | operands to memory. */ | |
1487 | case '0': case '1': case '2': case '3': case '4': | |
cd76ea33 | 1488 | case '5': case '6': case '7': case '8': case '9': |
2a230e9d | 1489 | if (constraint[j] >= '0' + noutputs) |
956d6950 JL |
1490 | { |
1491 | error | |
1492 | ("matching constraint references invalid operand number"); | |
1493 | return; | |
1494 | } | |
cd76ea33 | 1495 | |
1f06ee8d | 1496 | /* Try and find the real constraint for this dup. */ |
1afbe1c4 RH |
1497 | if ((j == 0 && c_len == 1) |
1498 | || (j == 1 && c_len == 2 && constraint[0] == '%')) | |
1f06ee8d RH |
1499 | { |
1500 | tree o = outputs; | |
1501 | for (j = constraint[j] - '0'; j > 0; --j) | |
1502 | o = TREE_CHAIN (o); | |
1503 | ||
1504 | c_len = TREE_STRING_LENGTH (TREE_PURPOSE (o)) - 1; | |
1505 | constraint = TREE_STRING_POINTER (TREE_PURPOSE (o)); | |
1506 | j = 0; | |
1507 | break; | |
1508 | } | |
1509 | ||
cd76ea33 RK |
1510 | /* ... fall through ... */ |
1511 | ||
1f06ee8d | 1512 | case 'p': case 'r': |
65fed0cb RK |
1513 | default: |
1514 | allows_reg = 1; | |
1515 | break; | |
1f06ee8d RH |
1516 | |
1517 | case 'g': | |
1518 | allows_reg = 1; | |
1519 | allows_mem = 1; | |
1520 | break; | |
28d81abb RK |
1521 | } |
1522 | ||
1f06ee8d | 1523 | if (! allows_reg && allows_mem) |
65fed0cb RK |
1524 | mark_addressable (TREE_VALUE (tail)); |
1525 | ||
1f06ee8d | 1526 | op = expand_expr (TREE_VALUE (tail), NULL_RTX, VOIDmode, 0); |
65fed0cb | 1527 | |
1afbe1c4 | 1528 | if (asm_operand_ok (op, constraint) <= 0) |
65fed0cb | 1529 | { |
1f06ee8d RH |
1530 | if (allows_reg) |
1531 | op = force_reg (TYPE_MODE (TREE_TYPE (TREE_VALUE (tail))), op); | |
1532 | else if (!allows_mem) | |
1533 | warning ("asm operand %d probably doesn't match constraints", i); | |
1534 | else if (CONSTANT_P (op)) | |
1535 | op = force_const_mem (TYPE_MODE (TREE_TYPE (TREE_VALUE (tail))), | |
1536 | op); | |
1537 | else if (GET_CODE (op) == REG | |
1538 | || GET_CODE (op) == SUBREG | |
1539 | || GET_CODE (op) == CONCAT) | |
1540 | { | |
1541 | tree type = TREE_TYPE (TREE_VALUE (tail)); | |
1542 | rtx memloc = assign_temp (type, 1, 1, 1); | |
65fed0cb | 1543 | |
1f06ee8d RH |
1544 | emit_move_insn (memloc, op); |
1545 | op = memloc; | |
1546 | } | |
1547 | else if (GET_CODE (op) == MEM && MEM_VOLATILE_P (op)) | |
1548 | /* We won't recognize volatile memory as available a | |
1549 | memory_operand at this point. Ignore it. */ | |
1550 | ; | |
1551 | else if (queued_subexp_p (op)) | |
1552 | ; | |
1553 | else | |
1554 | /* ??? Leave this only until we have experience with what | |
1555 | happens in combine and elsewhere when constraints are | |
1556 | not satisfied. */ | |
1557 | warning ("asm operand %d probably doesn't match constraints", i); | |
65fed0cb | 1558 | } |
1f06ee8d | 1559 | XVECEXP (body, 3, i) = op; |
2a230e9d | 1560 | |
28d81abb | 1561 | XVECEXP (body, 4, i) /* constraints */ |
38a448ca | 1562 | = gen_rtx_ASM_INPUT (TYPE_MODE (TREE_TYPE (TREE_VALUE (tail))), |
1f06ee8d | 1563 | orig_constraint); |
28d81abb RK |
1564 | i++; |
1565 | } | |
1566 | ||
1567 | /* Protect all the operands from the queue, | |
1568 | now that they have all been evaluated. */ | |
1569 | ||
235c5021 | 1570 | for (i = 0; i < ninputs - ninout; i++) |
28d81abb RK |
1571 | XVECEXP (body, 3, i) = protect_from_queue (XVECEXP (body, 3, i), 0); |
1572 | ||
1573 | for (i = 0; i < noutputs; i++) | |
1574 | output_rtx[i] = protect_from_queue (output_rtx[i], 1); | |
1575 | ||
235c5021 RK |
1576 | /* For in-out operands, copy output rtx to input rtx. */ |
1577 | for (i = 0; i < ninout; i++) | |
1578 | { | |
1579 | static char match[9+1][2] | |
1580 | = {"0", "1", "2", "3", "4", "5", "6", "7", "8", "9"}; | |
1581 | int j = inout_opnum[i]; | |
1582 | ||
1583 | XVECEXP (body, 3, ninputs - ninout + i) /* argvec */ | |
1584 | = output_rtx[j]; | |
1585 | XVECEXP (body, 4, ninputs - ninout + i) /* constraints */ | |
38a448ca | 1586 | = gen_rtx_ASM_INPUT (inout_mode[j], match[j]); |
235c5021 RK |
1587 | } |
1588 | ||
28d81abb RK |
1589 | /* Now, for each output, construct an rtx |
1590 | (set OUTPUT (asm_operands INSN OUTPUTNUMBER OUTPUTCONSTRAINT | |
1591 | ARGVEC CONSTRAINTS)) | |
1592 | If there is more than one, put them inside a PARALLEL. */ | |
1593 | ||
1594 | if (noutputs == 1 && nclobbers == 0) | |
1595 | { | |
1596 | XSTR (body, 1) = TREE_STRING_POINTER (TREE_PURPOSE (outputs)); | |
38a448ca | 1597 | insn = emit_insn (gen_rtx_SET (VOIDmode, output_rtx[0], body)); |
28d81abb RK |
1598 | } |
1599 | else if (noutputs == 0 && nclobbers == 0) | |
1600 | { | |
1601 | /* No output operands: put in a raw ASM_OPERANDS rtx. */ | |
1602 | insn = emit_insn (body); | |
1603 | } | |
1604 | else | |
1605 | { | |
1606 | rtx obody = body; | |
1607 | int num = noutputs; | |
1608 | if (num == 0) num = 1; | |
38a448ca | 1609 | body = gen_rtx_PARALLEL (VOIDmode, rtvec_alloc (num + nclobbers)); |
28d81abb RK |
1610 | |
1611 | /* For each output operand, store a SET. */ | |
1612 | ||
1613 | for (i = 0, tail = outputs; tail; tail = TREE_CHAIN (tail), i++) | |
1614 | { | |
1615 | XVECEXP (body, 0, i) | |
38a448ca RH |
1616 | = gen_rtx_SET (VOIDmode, |
1617 | output_rtx[i], | |
1618 | gen_rtx_ASM_OPERANDS (VOIDmode, | |
1619 | TREE_STRING_POINTER (string), | |
1620 | TREE_STRING_POINTER (TREE_PURPOSE (tail)), | |
1621 | i, argvec, constraints, | |
1622 | filename, line)); | |
28d81abb RK |
1623 | MEM_VOLATILE_P (SET_SRC (XVECEXP (body, 0, i))) = vol; |
1624 | } | |
1625 | ||
1626 | /* If there are no outputs (but there are some clobbers) | |
1627 | store the bare ASM_OPERANDS into the PARALLEL. */ | |
1628 | ||
1629 | if (i == 0) | |
1630 | XVECEXP (body, 0, i++) = obody; | |
1631 | ||
1632 | /* Store (clobber REG) for each clobbered register specified. */ | |
1633 | ||
b4ccaa16 | 1634 | for (tail = clobbers; tail; tail = TREE_CHAIN (tail)) |
28d81abb | 1635 | { |
28d81abb | 1636 | char *regname = TREE_STRING_POINTER (TREE_VALUE (tail)); |
b4ac57ab | 1637 | int j = decode_reg_name (regname); |
28d81abb | 1638 | |
b4ac57ab | 1639 | if (j < 0) |
28d81abb | 1640 | { |
c09e6498 | 1641 | if (j == -3) /* `cc', which is not a register */ |
dcfedcd0 RK |
1642 | continue; |
1643 | ||
c09e6498 RS |
1644 | if (j == -4) /* `memory', don't cache memory across asm */ |
1645 | { | |
bffc6177 | 1646 | XVECEXP (body, 0, i++) |
38a448ca RH |
1647 | = gen_rtx_CLOBBER (VOIDmode, |
1648 | gen_rtx_MEM (BLKmode, | |
1649 | gen_rtx_SCRATCH (VOIDmode))); | |
c09e6498 RS |
1650 | continue; |
1651 | } | |
1652 | ||
956d6950 | 1653 | /* Ignore unknown register, error already signaled. */ |
cc1f5387 | 1654 | continue; |
28d81abb RK |
1655 | } |
1656 | ||
1657 | /* Use QImode since that's guaranteed to clobber just one reg. */ | |
b4ccaa16 | 1658 | XVECEXP (body, 0, i++) |
38a448ca | 1659 | = gen_rtx_CLOBBER (VOIDmode, gen_rtx_REG (QImode, j)); |
28d81abb RK |
1660 | } |
1661 | ||
1662 | insn = emit_insn (body); | |
1663 | } | |
1664 | ||
1665 | free_temp_slots (); | |
1666 | } | |
1667 | \f | |
1668 | /* Generate RTL to evaluate the expression EXP | |
1669 | and remember it in case this is the VALUE in a ({... VALUE; }) constr. */ | |
1670 | ||
1671 | void | |
1672 | expand_expr_stmt (exp) | |
1673 | tree exp; | |
1674 | { | |
1675 | /* If -W, warn about statements with no side effects, | |
1676 | except for an explicit cast to void (e.g. for assert()), and | |
1677 | except inside a ({...}) where they may be useful. */ | |
1678 | if (expr_stmts_for_value == 0 && exp != error_mark_node) | |
1679 | { | |
1680 | if (! TREE_SIDE_EFFECTS (exp) && (extra_warnings || warn_unused) | |
1681 | && !(TREE_CODE (exp) == CONVERT_EXPR | |
1682 | && TREE_TYPE (exp) == void_type_node)) | |
1683 | warning_with_file_and_line (emit_filename, emit_lineno, | |
1684 | "statement with no effect"); | |
1685 | else if (warn_unused) | |
1686 | warn_if_unused_value (exp); | |
1687 | } | |
b6ec8c5f RK |
1688 | |
1689 | /* If EXP is of function type and we are expanding statements for | |
1690 | value, convert it to pointer-to-function. */ | |
1691 | if (expr_stmts_for_value && TREE_CODE (TREE_TYPE (exp)) == FUNCTION_TYPE) | |
1692 | exp = build1 (ADDR_EXPR, build_pointer_type (TREE_TYPE (exp)), exp); | |
1693 | ||
28d81abb | 1694 | last_expr_type = TREE_TYPE (exp); |
b941bcbc CB |
1695 | if (flag_syntax_only && ! expr_stmts_for_value) |
1696 | last_expr_value = 0; | |
1697 | else | |
37366632 RK |
1698 | last_expr_value = expand_expr (exp, |
1699 | (expr_stmts_for_value | |
1700 | ? NULL_RTX : const0_rtx), | |
28d81abb RK |
1701 | VOIDmode, 0); |
1702 | ||
1703 | /* If all we do is reference a volatile value in memory, | |
1704 | copy it to a register to be sure it is actually touched. */ | |
1705 | if (last_expr_value != 0 && GET_CODE (last_expr_value) == MEM | |
1706 | && TREE_THIS_VOLATILE (exp)) | |
1707 | { | |
6a5bbbe6 RS |
1708 | if (TYPE_MODE (TREE_TYPE (exp)) == VOIDmode) |
1709 | ; | |
1710 | else if (TYPE_MODE (TREE_TYPE (exp)) != BLKmode) | |
28d81abb RK |
1711 | copy_to_reg (last_expr_value); |
1712 | else | |
ddbe9812 RS |
1713 | { |
1714 | rtx lab = gen_label_rtx (); | |
1715 | ||
1716 | /* Compare the value with itself to reference it. */ | |
c5d5d461 JL |
1717 | emit_cmp_and_jump_insns (last_expr_value, last_expr_value, EQ, |
1718 | expand_expr (TYPE_SIZE (last_expr_type), | |
1719 | NULL_RTX, VOIDmode, 0), | |
1720 | BLKmode, 0, | |
1721 | TYPE_ALIGN (last_expr_type) / BITS_PER_UNIT, | |
1722 | lab); | |
ddbe9812 RS |
1723 | emit_label (lab); |
1724 | } | |
28d81abb RK |
1725 | } |
1726 | ||
1727 | /* If this expression is part of a ({...}) and is in memory, we may have | |
1728 | to preserve temporaries. */ | |
1729 | preserve_temp_slots (last_expr_value); | |
1730 | ||
1731 | /* Free any temporaries used to evaluate this expression. Any temporary | |
1732 | used as a result of this expression will already have been preserved | |
1733 | above. */ | |
1734 | free_temp_slots (); | |
1735 | ||
1736 | emit_queue (); | |
1737 | } | |
1738 | ||
1739 | /* Warn if EXP contains any computations whose results are not used. | |
1740 | Return 1 if a warning is printed; 0 otherwise. */ | |
1741 | ||
150a992a | 1742 | int |
28d81abb RK |
1743 | warn_if_unused_value (exp) |
1744 | tree exp; | |
1745 | { | |
1746 | if (TREE_USED (exp)) | |
1747 | return 0; | |
1748 | ||
1749 | switch (TREE_CODE (exp)) | |
1750 | { | |
1751 | case PREINCREMENT_EXPR: | |
1752 | case POSTINCREMENT_EXPR: | |
1753 | case PREDECREMENT_EXPR: | |
1754 | case POSTDECREMENT_EXPR: | |
1755 | case MODIFY_EXPR: | |
1756 | case INIT_EXPR: | |
1757 | case TARGET_EXPR: | |
1758 | case CALL_EXPR: | |
1759 | case METHOD_CALL_EXPR: | |
1760 | case RTL_EXPR: | |
81797aba | 1761 | case TRY_CATCH_EXPR: |
28d81abb RK |
1762 | case WITH_CLEANUP_EXPR: |
1763 | case EXIT_EXPR: | |
1764 | /* We don't warn about COND_EXPR because it may be a useful | |
1765 | construct if either arm contains a side effect. */ | |
1766 | case COND_EXPR: | |
1767 | return 0; | |
1768 | ||
1769 | case BIND_EXPR: | |
1770 | /* For a binding, warn if no side effect within it. */ | |
1771 | return warn_if_unused_value (TREE_OPERAND (exp, 1)); | |
1772 | ||
de73f171 RK |
1773 | case SAVE_EXPR: |
1774 | return warn_if_unused_value (TREE_OPERAND (exp, 1)); | |
1775 | ||
28d81abb RK |
1776 | case TRUTH_ORIF_EXPR: |
1777 | case TRUTH_ANDIF_EXPR: | |
1778 | /* In && or ||, warn if 2nd operand has no side effect. */ | |
1779 | return warn_if_unused_value (TREE_OPERAND (exp, 1)); | |
1780 | ||
1781 | case COMPOUND_EXPR: | |
a646a211 JM |
1782 | if (TREE_NO_UNUSED_WARNING (exp)) |
1783 | return 0; | |
28d81abb RK |
1784 | if (warn_if_unused_value (TREE_OPERAND (exp, 0))) |
1785 | return 1; | |
4d23e509 RS |
1786 | /* Let people do `(foo (), 0)' without a warning. */ |
1787 | if (TREE_CONSTANT (TREE_OPERAND (exp, 1))) | |
1788 | return 0; | |
28d81abb RK |
1789 | return warn_if_unused_value (TREE_OPERAND (exp, 1)); |
1790 | ||
1791 | case NOP_EXPR: | |
1792 | case CONVERT_EXPR: | |
b4ac57ab | 1793 | case NON_LVALUE_EXPR: |
28d81abb RK |
1794 | /* Don't warn about values cast to void. */ |
1795 | if (TREE_TYPE (exp) == void_type_node) | |
1796 | return 0; | |
1797 | /* Don't warn about conversions not explicit in the user's program. */ | |
1798 | if (TREE_NO_UNUSED_WARNING (exp)) | |
1799 | return 0; | |
1800 | /* Assignment to a cast usually results in a cast of a modify. | |
55cd1c09 JW |
1801 | Don't complain about that. There can be an arbitrary number of |
1802 | casts before the modify, so we must loop until we find the first | |
1803 | non-cast expression and then test to see if that is a modify. */ | |
1804 | { | |
1805 | tree tem = TREE_OPERAND (exp, 0); | |
1806 | ||
1807 | while (TREE_CODE (tem) == CONVERT_EXPR || TREE_CODE (tem) == NOP_EXPR) | |
1808 | tem = TREE_OPERAND (tem, 0); | |
1809 | ||
de73f171 RK |
1810 | if (TREE_CODE (tem) == MODIFY_EXPR || TREE_CODE (tem) == INIT_EXPR |
1811 | || TREE_CODE (tem) == CALL_EXPR) | |
55cd1c09 JW |
1812 | return 0; |
1813 | } | |
d1e1adfb | 1814 | goto warn; |
28d81abb | 1815 | |
d1e1adfb JM |
1816 | case INDIRECT_REF: |
1817 | /* Don't warn about automatic dereferencing of references, since | |
1818 | the user cannot control it. */ | |
1819 | if (TREE_CODE (TREE_TYPE (TREE_OPERAND (exp, 0))) == REFERENCE_TYPE) | |
1820 | return warn_if_unused_value (TREE_OPERAND (exp, 0)); | |
0f41302f | 1821 | /* ... fall through ... */ |
d1e1adfb | 1822 | |
28d81abb | 1823 | default: |
ddbe9812 RS |
1824 | /* Referencing a volatile value is a side effect, so don't warn. */ |
1825 | if ((TREE_CODE_CLASS (TREE_CODE (exp)) == 'd' | |
1826 | || TREE_CODE_CLASS (TREE_CODE (exp)) == 'r') | |
1827 | && TREE_THIS_VOLATILE (exp)) | |
1828 | return 0; | |
d1e1adfb | 1829 | warn: |
28d81abb RK |
1830 | warning_with_file_and_line (emit_filename, emit_lineno, |
1831 | "value computed is not used"); | |
1832 | return 1; | |
1833 | } | |
1834 | } | |
1835 | ||
1836 | /* Clear out the memory of the last expression evaluated. */ | |
1837 | ||
1838 | void | |
1839 | clear_last_expr () | |
1840 | { | |
1841 | last_expr_type = 0; | |
1842 | } | |
1843 | ||
1844 | /* Begin a statement which will return a value. | |
1845 | Return the RTL_EXPR for this statement expr. | |
1846 | The caller must save that value and pass it to expand_end_stmt_expr. */ | |
1847 | ||
1848 | tree | |
1849 | expand_start_stmt_expr () | |
1850 | { | |
ca695ac9 JB |
1851 | int momentary; |
1852 | tree t; | |
1853 | ||
28d81abb RK |
1854 | /* Make the RTL_EXPR node temporary, not momentary, |
1855 | so that rtl_expr_chain doesn't become garbage. */ | |
ca695ac9 JB |
1856 | momentary = suspend_momentary (); |
1857 | t = make_node (RTL_EXPR); | |
28d81abb | 1858 | resume_momentary (momentary); |
33c6ab80 | 1859 | do_pending_stack_adjust (); |
e922dbad | 1860 | start_sequence_for_rtl_expr (t); |
28d81abb RK |
1861 | NO_DEFER_POP; |
1862 | expr_stmts_for_value++; | |
1863 | return t; | |
1864 | } | |
1865 | ||
1866 | /* Restore the previous state at the end of a statement that returns a value. | |
1867 | Returns a tree node representing the statement's value and the | |
1868 | insns to compute the value. | |
1869 | ||
1870 | The nodes of that expression have been freed by now, so we cannot use them. | |
1871 | But we don't want to do that anyway; the expression has already been | |
1872 | evaluated and now we just want to use the value. So generate a RTL_EXPR | |
1873 | with the proper type and RTL value. | |
1874 | ||
1875 | If the last substatement was not an expression, | |
1876 | return something with type `void'. */ | |
1877 | ||
1878 | tree | |
1879 | expand_end_stmt_expr (t) | |
1880 | tree t; | |
1881 | { | |
1882 | OK_DEFER_POP; | |
1883 | ||
1884 | if (last_expr_type == 0) | |
1885 | { | |
1886 | last_expr_type = void_type_node; | |
1887 | last_expr_value = const0_rtx; | |
1888 | } | |
1889 | else if (last_expr_value == 0) | |
1890 | /* There are some cases where this can happen, such as when the | |
1891 | statement is void type. */ | |
1892 | last_expr_value = const0_rtx; | |
1893 | else if (GET_CODE (last_expr_value) != REG && ! CONSTANT_P (last_expr_value)) | |
1894 | /* Remove any possible QUEUED. */ | |
1895 | last_expr_value = protect_from_queue (last_expr_value, 0); | |
1896 | ||
1897 | emit_queue (); | |
1898 | ||
1899 | TREE_TYPE (t) = last_expr_type; | |
1900 | RTL_EXPR_RTL (t) = last_expr_value; | |
1901 | RTL_EXPR_SEQUENCE (t) = get_insns (); | |
1902 | ||
1903 | rtl_expr_chain = tree_cons (NULL_TREE, t, rtl_expr_chain); | |
1904 | ||
1905 | end_sequence (); | |
1906 | ||
1907 | /* Don't consider deleting this expr or containing exprs at tree level. */ | |
1908 | TREE_SIDE_EFFECTS (t) = 1; | |
1909 | /* Propagate volatility of the actual RTL expr. */ | |
1910 | TREE_THIS_VOLATILE (t) = volatile_refs_p (last_expr_value); | |
1911 | ||
1912 | last_expr_type = 0; | |
1913 | expr_stmts_for_value--; | |
1914 | ||
1915 | return t; | |
1916 | } | |
1917 | \f | |
28d81abb RK |
1918 | /* Generate RTL for the start of an if-then. COND is the expression |
1919 | whose truth should be tested. | |
1920 | ||
1921 | If EXITFLAG is nonzero, this conditional is visible to | |
1922 | `exit_something'. */ | |
1923 | ||
1924 | void | |
1925 | expand_start_cond (cond, exitflag) | |
1926 | tree cond; | |
1927 | int exitflag; | |
1928 | { | |
1929 | struct nesting *thiscond = ALLOC_NESTING (); | |
1930 | ||
1931 | /* Make an entry on cond_stack for the cond we are entering. */ | |
1932 | ||
1933 | thiscond->next = cond_stack; | |
1934 | thiscond->all = nesting_stack; | |
1935 | thiscond->depth = ++nesting_depth; | |
1936 | thiscond->data.cond.next_label = gen_label_rtx (); | |
1937 | /* Before we encounter an `else', we don't need a separate exit label | |
1938 | unless there are supposed to be exit statements | |
1939 | to exit this conditional. */ | |
1940 | thiscond->exit_label = exitflag ? gen_label_rtx () : 0; | |
1941 | thiscond->data.cond.endif_label = thiscond->exit_label; | |
1942 | cond_stack = thiscond; | |
1943 | nesting_stack = thiscond; | |
1944 | ||
b93a436e | 1945 | do_jump (cond, thiscond->data.cond.next_label, NULL_RTX); |
28d81abb RK |
1946 | } |
1947 | ||
1948 | /* Generate RTL between then-clause and the elseif-clause | |
1949 | of an if-then-elseif-.... */ | |
1950 | ||
1951 | void | |
1952 | expand_start_elseif (cond) | |
1953 | tree cond; | |
1954 | { | |
1955 | if (cond_stack->data.cond.endif_label == 0) | |
1956 | cond_stack->data.cond.endif_label = gen_label_rtx (); | |
1957 | emit_jump (cond_stack->data.cond.endif_label); | |
1958 | emit_label (cond_stack->data.cond.next_label); | |
1959 | cond_stack->data.cond.next_label = gen_label_rtx (); | |
37366632 | 1960 | do_jump (cond, cond_stack->data.cond.next_label, NULL_RTX); |
28d81abb RK |
1961 | } |
1962 | ||
1963 | /* Generate RTL between the then-clause and the else-clause | |
1964 | of an if-then-else. */ | |
1965 | ||
1966 | void | |
1967 | expand_start_else () | |
1968 | { | |
1969 | if (cond_stack->data.cond.endif_label == 0) | |
1970 | cond_stack->data.cond.endif_label = gen_label_rtx (); | |
ca695ac9 | 1971 | |
28d81abb RK |
1972 | emit_jump (cond_stack->data.cond.endif_label); |
1973 | emit_label (cond_stack->data.cond.next_label); | |
0f41302f | 1974 | cond_stack->data.cond.next_label = 0; /* No more _else or _elseif calls. */ |
28d81abb RK |
1975 | } |
1976 | ||
d947ba59 RK |
1977 | /* After calling expand_start_else, turn this "else" into an "else if" |
1978 | by providing another condition. */ | |
1979 | ||
1980 | void | |
1981 | expand_elseif (cond) | |
1982 | tree cond; | |
1983 | { | |
1984 | cond_stack->data.cond.next_label = gen_label_rtx (); | |
1985 | do_jump (cond, cond_stack->data.cond.next_label, NULL_RTX); | |
1986 | } | |
1987 | ||
28d81abb RK |
1988 | /* Generate RTL for the end of an if-then. |
1989 | Pop the record for it off of cond_stack. */ | |
1990 | ||
1991 | void | |
1992 | expand_end_cond () | |
1993 | { | |
1994 | struct nesting *thiscond = cond_stack; | |
1995 | ||
b93a436e JL |
1996 | do_pending_stack_adjust (); |
1997 | if (thiscond->data.cond.next_label) | |
1998 | emit_label (thiscond->data.cond.next_label); | |
1999 | if (thiscond->data.cond.endif_label) | |
2000 | emit_label (thiscond->data.cond.endif_label); | |
28d81abb RK |
2001 | |
2002 | POPSTACK (cond_stack); | |
2003 | last_expr_type = 0; | |
2004 | } | |
ca695ac9 JB |
2005 | |
2006 | ||
28d81abb RK |
2007 | \f |
2008 | /* Generate RTL for the start of a loop. EXIT_FLAG is nonzero if this | |
2009 | loop should be exited by `exit_something'. This is a loop for which | |
2010 | `expand_continue' will jump to the top of the loop. | |
2011 | ||
2012 | Make an entry on loop_stack to record the labels associated with | |
2013 | this loop. */ | |
2014 | ||
2015 | struct nesting * | |
2016 | expand_start_loop (exit_flag) | |
2017 | int exit_flag; | |
2018 | { | |
2019 | register struct nesting *thisloop = ALLOC_NESTING (); | |
2020 | ||
2021 | /* Make an entry on loop_stack for the loop we are entering. */ | |
2022 | ||
2023 | thisloop->next = loop_stack; | |
2024 | thisloop->all = nesting_stack; | |
2025 | thisloop->depth = ++nesting_depth; | |
2026 | thisloop->data.loop.start_label = gen_label_rtx (); | |
2027 | thisloop->data.loop.end_label = gen_label_rtx (); | |
8afad312 | 2028 | thisloop->data.loop.alt_end_label = 0; |
28d81abb RK |
2029 | thisloop->data.loop.continue_label = thisloop->data.loop.start_label; |
2030 | thisloop->exit_label = exit_flag ? thisloop->data.loop.end_label : 0; | |
2031 | loop_stack = thisloop; | |
2032 | nesting_stack = thisloop; | |
2033 | ||
2034 | do_pending_stack_adjust (); | |
2035 | emit_queue (); | |
37366632 | 2036 | emit_note (NULL_PTR, NOTE_INSN_LOOP_BEG); |
28d81abb RK |
2037 | emit_label (thisloop->data.loop.start_label); |
2038 | ||
2039 | return thisloop; | |
2040 | } | |
2041 | ||
2042 | /* Like expand_start_loop but for a loop where the continuation point | |
2043 | (for expand_continue_loop) will be specified explicitly. */ | |
2044 | ||
2045 | struct nesting * | |
2046 | expand_start_loop_continue_elsewhere (exit_flag) | |
2047 | int exit_flag; | |
2048 | { | |
2049 | struct nesting *thisloop = expand_start_loop (exit_flag); | |
2050 | loop_stack->data.loop.continue_label = gen_label_rtx (); | |
2051 | return thisloop; | |
2052 | } | |
2053 | ||
2054 | /* Specify the continuation point for a loop started with | |
2055 | expand_start_loop_continue_elsewhere. | |
2056 | Use this at the point in the code to which a continue statement | |
2057 | should jump. */ | |
2058 | ||
2059 | void | |
2060 | expand_loop_continue_here () | |
2061 | { | |
2062 | do_pending_stack_adjust (); | |
37366632 | 2063 | emit_note (NULL_PTR, NOTE_INSN_LOOP_CONT); |
28d81abb RK |
2064 | emit_label (loop_stack->data.loop.continue_label); |
2065 | } | |
2066 | ||
2067 | /* Finish a loop. Generate a jump back to the top and the loop-exit label. | |
2068 | Pop the block off of loop_stack. */ | |
2069 | ||
2070 | void | |
2071 | expand_end_loop () | |
2072 | { | |
0720f6fb MM |
2073 | rtx start_label = loop_stack->data.loop.start_label; |
2074 | rtx insn = get_last_insn (); | |
28d81abb RK |
2075 | |
2076 | /* Mark the continue-point at the top of the loop if none elsewhere. */ | |
2077 | if (start_label == loop_stack->data.loop.continue_label) | |
2078 | emit_note_before (NOTE_INSN_LOOP_CONT, start_label); | |
2079 | ||
2080 | do_pending_stack_adjust (); | |
2081 | ||
93de5c31 MM |
2082 | /* If optimizing, perhaps reorder the loop. If the loop starts with |
2083 | a loop exit, roll that to the end where it will optimize together | |
2084 | with the jump back. | |
2085 | ||
2086 | We look for the conditional branch to the exit, except that once | |
2087 | we find such a branch, we don't look past 30 instructions. | |
2088 | ||
2089 | In more detail, if the loop presently looks like this (in pseudo-C): | |
2090 | ||
2091 | start_label: | |
2092 | if (test) goto end_label; | |
2093 | body; | |
2094 | goto start_label; | |
0720f6fb | 2095 | end_label: |
93de5c31 MM |
2096 | |
2097 | transform it to look like: | |
2098 | ||
2099 | goto start_label; | |
2100 | newstart_label: | |
2101 | body; | |
2102 | start_label: | |
2103 | if (test) goto end_label; | |
2104 | goto newstart_label; | |
0720f6fb | 2105 | end_label: |
93de5c31 MM |
2106 | |
2107 | Here, the `test' may actually consist of some reasonably complex | |
2108 | code, terminating in a test. */ | |
0720f6fb | 2109 | |
28d81abb RK |
2110 | if (optimize |
2111 | && | |
2112 | ! (GET_CODE (insn) == JUMP_INSN | |
2113 | && GET_CODE (PATTERN (insn)) == SET | |
2114 | && SET_DEST (PATTERN (insn)) == pc_rtx | |
2115 | && GET_CODE (SET_SRC (PATTERN (insn))) == IF_THEN_ELSE)) | |
2116 | { | |
93de5c31 | 2117 | int eh_regions = 0; |
0720f6fb MM |
2118 | int num_insns = 0; |
2119 | rtx last_test_insn = NULL_RTX; | |
93de5c31 | 2120 | |
28d81abb RK |
2121 | /* Scan insns from the top of the loop looking for a qualified |
2122 | conditional exit. */ | |
2123 | for (insn = NEXT_INSN (loop_stack->data.loop.start_label); insn; | |
2124 | insn = NEXT_INSN (insn)) | |
2125 | { | |
93de5c31 MM |
2126 | if (GET_CODE (insn) == NOTE) |
2127 | { | |
2128 | if (optimize < 2 | |
2129 | && (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG | |
2130 | || NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)) | |
2131 | /* The code that actually moves the exit test will | |
2132 | carefully leave BLOCK notes in their original | |
2133 | location. That means, however, that we can't debug | |
2134 | the exit test itself. So, we refuse to move code | |
2135 | containing BLOCK notes at low optimization levels. */ | |
2136 | break; | |
2137 | ||
2138 | if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EH_REGION_BEG) | |
2139 | ++eh_regions; | |
2140 | else if (NOTE_LINE_NUMBER (insn) == NOTE_INSN_EH_REGION_END) | |
2141 | { | |
2142 | --eh_regions; | |
2143 | if (eh_regions < 0) | |
2144 | /* We've come to the end of an EH region, but | |
2145 | never saw the beginning of that region. That | |
2146 | means that an EH region begins before the top | |
2147 | of the loop, and ends in the middle of it. The | |
2148 | existence of such a situation violates a basic | |
2149 | assumption in this code, since that would imply | |
2150 | that even when EH_REGIONS is zero, we might | |
2151 | move code out of an exception region. */ | |
2152 | abort (); | |
2153 | } | |
28d81abb | 2154 | |
93de5c31 MM |
2155 | /* We already know this INSN is a NOTE, so there's no |
2156 | point in looking at it to see if it's a JUMP. */ | |
2157 | continue; | |
2158 | } | |
28d81abb RK |
2159 | |
2160 | if (GET_CODE (insn) == JUMP_INSN || GET_CODE (insn) == INSN) | |
2161 | num_insns++; | |
2162 | ||
2163 | if (last_test_insn && num_insns > 30) | |
2164 | break; | |
2165 | ||
93de5c31 MM |
2166 | if (eh_regions > 0) |
2167 | /* We don't want to move a partial EH region. Consider: | |
2168 | ||
2169 | while ( ( { try { | |
2170 | if (cond ()) 0; | |
2171 | else { | |
2172 | bar(); | |
2173 | 1; | |
2174 | } | |
2175 | } catch (...) { | |
2176 | 1; | |
2177 | } )) { | |
2178 | body; | |
2179 | } | |
2180 | ||
2181 | This isn't legal C++, but here's what it's supposed to | |
2182 | mean: if cond() is true, stop looping. Otherwise, | |
2183 | call bar, and keep looping. In addition, if cond | |
2184 | throws an exception, catch it and keep looping. Such | |
2185 | constructs are certainy legal in LISP. | |
2186 | ||
2187 | We should not move the `if (cond()) 0' test since then | |
2188 | the EH-region for the try-block would be broken up. | |
2189 | (In this case we would the EH_BEG note for the `try' | |
2190 | and `if cond()' but not the call to bar() or the | |
2191 | EH_END note.) | |
2192 | ||
2193 | So we don't look for tests within an EH region. */ | |
2194 | continue; | |
2195 | ||
0720f6fb | 2196 | if (GET_CODE (insn) == JUMP_INSN |
28d81abb | 2197 | && GET_CODE (PATTERN (insn)) == SET |
0720f6fb MM |
2198 | && SET_DEST (PATTERN (insn)) == pc_rtx) |
2199 | { | |
2200 | /* This is indeed a jump. */ | |
2201 | rtx dest1 = NULL_RTX; | |
2202 | rtx dest2 = NULL_RTX; | |
2203 | rtx potential_last_test; | |
2204 | if (GET_CODE (SET_SRC (PATTERN (insn))) == IF_THEN_ELSE) | |
2205 | { | |
2206 | /* A conditional jump. */ | |
2207 | dest1 = XEXP (SET_SRC (PATTERN (insn)), 1); | |
2208 | dest2 = XEXP (SET_SRC (PATTERN (insn)), 2); | |
2209 | potential_last_test = insn; | |
2210 | } | |
2211 | else | |
2212 | { | |
2213 | /* An unconditional jump. */ | |
2214 | dest1 = SET_SRC (PATTERN (insn)); | |
2215 | /* Include the BARRIER after the JUMP. */ | |
2216 | potential_last_test = NEXT_INSN (insn); | |
2217 | } | |
2218 | ||
2219 | do { | |
2220 | if (dest1 && GET_CODE (dest1) == LABEL_REF | |
2221 | && ((XEXP (dest1, 0) | |
2222 | == loop_stack->data.loop.alt_end_label) | |
2223 | || (XEXP (dest1, 0) | |
2224 | == loop_stack->data.loop.end_label))) | |
2225 | { | |
2226 | last_test_insn = potential_last_test; | |
2227 | break; | |
2228 | } | |
2229 | ||
2230 | /* If this was a conditional jump, there may be | |
2231 | another label at which we should look. */ | |
2232 | dest1 = dest2; | |
2233 | dest2 = NULL_RTX; | |
2234 | } while (dest1); | |
2235 | } | |
28d81abb RK |
2236 | } |
2237 | ||
2238 | if (last_test_insn != 0 && last_test_insn != get_last_insn ()) | |
2239 | { | |
2240 | /* We found one. Move everything from there up | |
2241 | to the end of the loop, and add a jump into the loop | |
2242 | to jump to there. */ | |
2243 | register rtx newstart_label = gen_label_rtx (); | |
2244 | register rtx start_move = start_label; | |
93de5c31 | 2245 | rtx next_insn; |
28d81abb | 2246 | |
b4ac57ab | 2247 | /* If the start label is preceded by a NOTE_INSN_LOOP_CONT note, |
28d81abb RK |
2248 | then we want to move this note also. */ |
2249 | if (GET_CODE (PREV_INSN (start_move)) == NOTE | |
2250 | && (NOTE_LINE_NUMBER (PREV_INSN (start_move)) | |
2251 | == NOTE_INSN_LOOP_CONT)) | |
2252 | start_move = PREV_INSN (start_move); | |
2253 | ||
2254 | emit_label_after (newstart_label, PREV_INSN (start_move)); | |
93de5c31 MM |
2255 | |
2256 | /* Actually move the insns. Start at the beginning, and | |
2257 | keep copying insns until we've copied the | |
2258 | last_test_insn. */ | |
2259 | for (insn = start_move; insn; insn = next_insn) | |
2260 | { | |
2261 | /* Figure out which insn comes after this one. We have | |
2262 | to do this before we move INSN. */ | |
2263 | if (insn == last_test_insn) | |
2264 | /* We've moved all the insns. */ | |
2265 | next_insn = NULL_RTX; | |
2266 | else | |
2267 | next_insn = NEXT_INSN (insn); | |
2268 | ||
2269 | if (GET_CODE (insn) == NOTE | |
2270 | && (NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_BEG | |
2271 | || NOTE_LINE_NUMBER (insn) == NOTE_INSN_BLOCK_END)) | |
2272 | /* We don't want to move NOTE_INSN_BLOCK_BEGs or | |
2273 | NOTE_INSN_BLOCK_ENDs because the correct generation | |
2274 | of debugging information depends on these appearing | |
2275 | in the same order in the RTL and in the tree | |
2276 | structure, where they are represented as BLOCKs. | |
2277 | So, we don't move block notes. Of course, moving | |
2278 | the code inside the block is likely to make it | |
2279 | impossible to debug the instructions in the exit | |
2280 | test, but such is the price of optimization. */ | |
2281 | continue; | |
2282 | ||
2283 | /* Move the INSN. */ | |
2284 | reorder_insns (insn, insn, get_last_insn ()); | |
2285 | } | |
2286 | ||
28d81abb RK |
2287 | emit_jump_insn_after (gen_jump (start_label), |
2288 | PREV_INSN (newstart_label)); | |
2289 | emit_barrier_after (PREV_INSN (newstart_label)); | |
2290 | start_label = newstart_label; | |
2291 | } | |
2292 | } | |
2293 | ||
2294 | emit_jump (start_label); | |
37366632 | 2295 | emit_note (NULL_PTR, NOTE_INSN_LOOP_END); |
28d81abb RK |
2296 | emit_label (loop_stack->data.loop.end_label); |
2297 | ||
2298 | POPSTACK (loop_stack); | |
2299 | ||
2300 | last_expr_type = 0; | |
2301 | } | |
2302 | ||
2303 | /* Generate a jump to the current loop's continue-point. | |
2304 | This is usually the top of the loop, but may be specified | |
2305 | explicitly elsewhere. If not currently inside a loop, | |
2306 | return 0 and do nothing; caller will print an error message. */ | |
2307 | ||
2308 | int | |
2309 | expand_continue_loop (whichloop) | |
2310 | struct nesting *whichloop; | |
2311 | { | |
2312 | last_expr_type = 0; | |
2313 | if (whichloop == 0) | |
2314 | whichloop = loop_stack; | |
2315 | if (whichloop == 0) | |
2316 | return 0; | |
37366632 RK |
2317 | expand_goto_internal (NULL_TREE, whichloop->data.loop.continue_label, |
2318 | NULL_RTX); | |
28d81abb RK |
2319 | return 1; |
2320 | } | |
2321 | ||
2322 | /* Generate a jump to exit the current loop. If not currently inside a loop, | |
2323 | return 0 and do nothing; caller will print an error message. */ | |
2324 | ||
2325 | int | |
2326 | expand_exit_loop (whichloop) | |
2327 | struct nesting *whichloop; | |
2328 | { | |
2329 | last_expr_type = 0; | |
2330 | if (whichloop == 0) | |
2331 | whichloop = loop_stack; | |
2332 | if (whichloop == 0) | |
2333 | return 0; | |
37366632 | 2334 | expand_goto_internal (NULL_TREE, whichloop->data.loop.end_label, NULL_RTX); |
28d81abb RK |
2335 | return 1; |
2336 | } | |
2337 | ||
2338 | /* Generate a conditional jump to exit the current loop if COND | |
2339 | evaluates to zero. If not currently inside a loop, | |
2340 | return 0 and do nothing; caller will print an error message. */ | |
2341 | ||
2342 | int | |
2343 | expand_exit_loop_if_false (whichloop, cond) | |
2344 | struct nesting *whichloop; | |
2345 | tree cond; | |
2346 | { | |
b93a436e JL |
2347 | rtx label = gen_label_rtx (); |
2348 | rtx last_insn; | |
28d81abb | 2349 | last_expr_type = 0; |
b93a436e | 2350 | |
28d81abb RK |
2351 | if (whichloop == 0) |
2352 | whichloop = loop_stack; | |
2353 | if (whichloop == 0) | |
2354 | return 0; | |
b93a436e JL |
2355 | /* In order to handle fixups, we actually create a conditional jump |
2356 | around a unconditional branch to exit the loop. If fixups are | |
2357 | necessary, they go before the unconditional branch. */ | |
d902c7ea | 2358 | |
b93a436e JL |
2359 | |
2360 | do_jump (cond, NULL_RTX, label); | |
2361 | last_insn = get_last_insn (); | |
2362 | if (GET_CODE (last_insn) == CODE_LABEL) | |
2363 | whichloop->data.loop.alt_end_label = last_insn; | |
2364 | expand_goto_internal (NULL_TREE, whichloop->data.loop.end_label, | |
2365 | NULL_RTX); | |
2366 | emit_label (label); | |
ca695ac9 | 2367 | |
28d81abb RK |
2368 | return 1; |
2369 | } | |
2370 | ||
4a050cc2 JL |
2371 | /* Return nonzero if the loop nest is empty. Else return zero. */ |
2372 | ||
2373 | int | |
2374 | stmt_loop_nest_empty () | |
2375 | { | |
2376 | return (loop_stack == NULL); | |
2377 | } | |
2378 | ||
28d81abb RK |
2379 | /* Return non-zero if we should preserve sub-expressions as separate |
2380 | pseudos. We never do so if we aren't optimizing. We always do so | |
2381 | if -fexpensive-optimizations. | |
2382 | ||
2383 | Otherwise, we only do so if we are in the "early" part of a loop. I.e., | |
2384 | the loop may still be a small one. */ | |
2385 | ||
2386 | int | |
2387 | preserve_subexpressions_p () | |
2388 | { | |
2389 | rtx insn; | |
2390 | ||
2391 | if (flag_expensive_optimizations) | |
2392 | return 1; | |
2393 | ||
2394 | if (optimize == 0 || loop_stack == 0) | |
2395 | return 0; | |
2396 | ||
2397 | insn = get_last_insn_anywhere (); | |
2398 | ||
2399 | return (insn | |
2400 | && (INSN_UID (insn) - INSN_UID (loop_stack->data.loop.start_label) | |
2401 | < n_non_fixed_regs * 3)); | |
2402 | ||
2403 | } | |
2404 | ||
2405 | /* Generate a jump to exit the current loop, conditional, binding contour | |
2406 | or case statement. Not all such constructs are visible to this function, | |
2407 | only those started with EXIT_FLAG nonzero. Individual languages use | |
2408 | the EXIT_FLAG parameter to control which kinds of constructs you can | |
2409 | exit this way. | |
2410 | ||
2411 | If not currently inside anything that can be exited, | |
2412 | return 0 and do nothing; caller will print an error message. */ | |
2413 | ||
2414 | int | |
2415 | expand_exit_something () | |
2416 | { | |
2417 | struct nesting *n; | |
2418 | last_expr_type = 0; | |
2419 | for (n = nesting_stack; n; n = n->all) | |
2420 | if (n->exit_label != 0) | |
2421 | { | |
37366632 | 2422 | expand_goto_internal (NULL_TREE, n->exit_label, NULL_RTX); |
28d81abb RK |
2423 | return 1; |
2424 | } | |
2425 | ||
2426 | return 0; | |
2427 | } | |
2428 | \f | |
2429 | /* Generate RTL to return from the current function, with no value. | |
2430 | (That is, we do not do anything about returning any value.) */ | |
2431 | ||
2432 | void | |
2433 | expand_null_return () | |
2434 | { | |
2435 | struct nesting *block = block_stack; | |
2436 | rtx last_insn = 0; | |
2437 | ||
2438 | /* Does any pending block have cleanups? */ | |
2439 | ||
2440 | while (block && block->data.block.cleanups == 0) | |
2441 | block = block->next; | |
2442 | ||
2443 | /* If yes, use a goto to return, since that runs cleanups. */ | |
2444 | ||
2445 | expand_null_return_1 (last_insn, block != 0); | |
2446 | } | |
2447 | ||
2448 | /* Generate RTL to return from the current function, with value VAL. */ | |
2449 | ||
8d800403 | 2450 | static void |
28d81abb RK |
2451 | expand_value_return (val) |
2452 | rtx val; | |
2453 | { | |
2454 | struct nesting *block = block_stack; | |
2455 | rtx last_insn = get_last_insn (); | |
2456 | rtx return_reg = DECL_RTL (DECL_RESULT (current_function_decl)); | |
2457 | ||
2458 | /* Copy the value to the return location | |
2459 | unless it's already there. */ | |
2460 | ||
2461 | if (return_reg != val) | |
77636079 RS |
2462 | { |
2463 | #ifdef PROMOTE_FUNCTION_RETURN | |
77636079 RS |
2464 | tree type = TREE_TYPE (DECL_RESULT (current_function_decl)); |
2465 | int unsignedp = TREE_UNSIGNED (type); | |
28612f9e RK |
2466 | enum machine_mode mode |
2467 | = promote_mode (type, DECL_MODE (DECL_RESULT (current_function_decl)), | |
2468 | &unsignedp, 1); | |
77636079 RS |
2469 | |
2470 | if (GET_MODE (val) != VOIDmode && GET_MODE (val) != mode) | |
3af6dfd8 | 2471 | convert_move (return_reg, val, unsignedp); |
77636079 RS |
2472 | else |
2473 | #endif | |
2474 | emit_move_insn (return_reg, val); | |
2475 | } | |
28d81abb RK |
2476 | if (GET_CODE (return_reg) == REG |
2477 | && REGNO (return_reg) < FIRST_PSEUDO_REGISTER) | |
38a448ca | 2478 | emit_insn (gen_rtx_USE (VOIDmode, return_reg)); |
e5eeae65 JW |
2479 | /* Handle calls that return values in multiple non-contiguous locations. |
2480 | The Irix 6 ABI has examples of this. */ | |
2481 | else if (GET_CODE (return_reg) == PARALLEL) | |
2482 | { | |
2483 | int i; | |
2484 | ||
2485 | for (i = 0; i < XVECLEN (return_reg, 0); i++) | |
2486 | { | |
2487 | rtx x = XEXP (XVECEXP (return_reg, 0, i), 0); | |
2488 | ||
2489 | if (GET_CODE (x) == REG | |
2490 | && REGNO (x) < FIRST_PSEUDO_REGISTER) | |
38a448ca | 2491 | emit_insn (gen_rtx_USE (VOIDmode, x)); |
e5eeae65 JW |
2492 | } |
2493 | } | |
28d81abb RK |
2494 | |
2495 | /* Does any pending block have cleanups? */ | |
2496 | ||
2497 | while (block && block->data.block.cleanups == 0) | |
2498 | block = block->next; | |
2499 | ||
2500 | /* If yes, use a goto to return, since that runs cleanups. | |
2501 | Use LAST_INSN to put cleanups *before* the move insn emitted above. */ | |
2502 | ||
2503 | expand_null_return_1 (last_insn, block != 0); | |
2504 | } | |
2505 | ||
2506 | /* Output a return with no value. If LAST_INSN is nonzero, | |
2507 | pretend that the return takes place after LAST_INSN. | |
2508 | If USE_GOTO is nonzero then don't use a return instruction; | |
2509 | go to the return label instead. This causes any cleanups | |
2510 | of pending blocks to be executed normally. */ | |
2511 | ||
2512 | static void | |
2513 | expand_null_return_1 (last_insn, use_goto) | |
2514 | rtx last_insn; | |
2515 | int use_goto; | |
2516 | { | |
2517 | rtx end_label = cleanup_label ? cleanup_label : return_label; | |
2518 | ||
2519 | clear_pending_stack_adjust (); | |
2520 | do_pending_stack_adjust (); | |
2521 | last_expr_type = 0; | |
2522 | ||
2523 | /* PCC-struct return always uses an epilogue. */ | |
2524 | if (current_function_returns_pcc_struct || use_goto) | |
2525 | { | |
2526 | if (end_label == 0) | |
2527 | end_label = return_label = gen_label_rtx (); | |
37366632 | 2528 | expand_goto_internal (NULL_TREE, end_label, last_insn); |
28d81abb RK |
2529 | return; |
2530 | } | |
2531 | ||
2532 | /* Otherwise output a simple return-insn if one is available, | |
2533 | unless it won't do the job. */ | |
2534 | #ifdef HAVE_return | |
2535 | if (HAVE_return && use_goto == 0 && cleanup_label == 0) | |
2536 | { | |
2537 | emit_jump_insn (gen_return ()); | |
2538 | emit_barrier (); | |
2539 | return; | |
2540 | } | |
2541 | #endif | |
2542 | ||
2543 | /* Otherwise jump to the epilogue. */ | |
37366632 | 2544 | expand_goto_internal (NULL_TREE, end_label, last_insn); |
28d81abb RK |
2545 | } |
2546 | \f | |
2547 | /* Generate RTL to evaluate the expression RETVAL and return it | |
2548 | from the current function. */ | |
2549 | ||
2550 | void | |
2551 | expand_return (retval) | |
2552 | tree retval; | |
2553 | { | |
2554 | /* If there are any cleanups to be performed, then they will | |
2555 | be inserted following LAST_INSN. It is desirable | |
2556 | that the last_insn, for such purposes, should be the | |
2557 | last insn before computing the return value. Otherwise, cleanups | |
2558 | which call functions can clobber the return value. */ | |
2559 | /* ??? rms: I think that is erroneous, because in C++ it would | |
2560 | run destructors on variables that might be used in the subsequent | |
2561 | computation of the return value. */ | |
2562 | rtx last_insn = 0; | |
2563 | register rtx val = 0; | |
2564 | register rtx op0; | |
2565 | tree retval_rhs; | |
2566 | int cleanups; | |
28d81abb RK |
2567 | |
2568 | /* If function wants no value, give it none. */ | |
2569 | if (TREE_CODE (TREE_TYPE (TREE_TYPE (current_function_decl))) == VOID_TYPE) | |
2570 | { | |
37366632 | 2571 | expand_expr (retval, NULL_RTX, VOIDmode, 0); |
7e70e7c5 | 2572 | emit_queue (); |
28d81abb RK |
2573 | expand_null_return (); |
2574 | return; | |
2575 | } | |
2576 | ||
2577 | /* Are any cleanups needed? E.g. C++ destructors to be run? */ | |
7a9a00be MS |
2578 | /* This is not sufficient. We also need to watch for cleanups of the |
2579 | expression we are about to expand. Unfortunately, we cannot know | |
2580 | if it has cleanups until we expand it, and we want to change how we | |
2581 | expand it depending upon if we need cleanups. We can't win. */ | |
2582 | #if 0 | |
28d81abb | 2583 | cleanups = any_pending_cleanups (1); |
7a9a00be MS |
2584 | #else |
2585 | cleanups = 1; | |
2586 | #endif | |
28d81abb RK |
2587 | |
2588 | if (TREE_CODE (retval) == RESULT_DECL) | |
2589 | retval_rhs = retval; | |
2590 | else if ((TREE_CODE (retval) == MODIFY_EXPR || TREE_CODE (retval) == INIT_EXPR) | |
2591 | && TREE_CODE (TREE_OPERAND (retval, 0)) == RESULT_DECL) | |
2592 | retval_rhs = TREE_OPERAND (retval, 1); | |
2593 | else if (TREE_TYPE (retval) == void_type_node) | |
2594 | /* Recognize tail-recursive call to void function. */ | |
2595 | retval_rhs = retval; | |
2596 | else | |
2597 | retval_rhs = NULL_TREE; | |
2598 | ||
2599 | /* Only use `last_insn' if there are cleanups which must be run. */ | |
2600 | if (cleanups || cleanup_label != 0) | |
2601 | last_insn = get_last_insn (); | |
2602 | ||
2603 | /* Distribute return down conditional expr if either of the sides | |
2604 | may involve tail recursion (see test below). This enhances the number | |
2605 | of tail recursions we see. Don't do this always since it can produce | |
2606 | sub-optimal code in some cases and we distribute assignments into | |
2607 | conditional expressions when it would help. */ | |
2608 | ||
2609 | if (optimize && retval_rhs != 0 | |
2610 | && frame_offset == 0 | |
2611 | && TREE_CODE (retval_rhs) == COND_EXPR | |
2612 | && (TREE_CODE (TREE_OPERAND (retval_rhs, 1)) == CALL_EXPR | |
2613 | || TREE_CODE (TREE_OPERAND (retval_rhs, 2)) == CALL_EXPR)) | |
2614 | { | |
2615 | rtx label = gen_label_rtx (); | |
a0a34f94 RK |
2616 | tree expr; |
2617 | ||
37366632 | 2618 | do_jump (TREE_OPERAND (retval_rhs, 0), label, NULL_RTX); |
dd98f85c | 2619 | expr = build (MODIFY_EXPR, TREE_TYPE (TREE_TYPE (current_function_decl)), |
a0a34f94 RK |
2620 | DECL_RESULT (current_function_decl), |
2621 | TREE_OPERAND (retval_rhs, 1)); | |
2622 | TREE_SIDE_EFFECTS (expr) = 1; | |
2623 | expand_return (expr); | |
28d81abb | 2624 | emit_label (label); |
a0a34f94 | 2625 | |
dd98f85c | 2626 | expr = build (MODIFY_EXPR, TREE_TYPE (TREE_TYPE (current_function_decl)), |
a0a34f94 RK |
2627 | DECL_RESULT (current_function_decl), |
2628 | TREE_OPERAND (retval_rhs, 2)); | |
2629 | TREE_SIDE_EFFECTS (expr) = 1; | |
2630 | expand_return (expr); | |
28d81abb RK |
2631 | return; |
2632 | } | |
2633 | ||
642cac7b | 2634 | /* Attempt to optimize the call if it is tail recursive. */ |
564ea051 JW |
2635 | if (optimize_tail_recursion (retval_rhs, last_insn)) |
2636 | return; | |
642cac7b | 2637 | |
28d81abb RK |
2638 | #ifdef HAVE_return |
2639 | /* This optimization is safe if there are local cleanups | |
2640 | because expand_null_return takes care of them. | |
2641 | ??? I think it should also be safe when there is a cleanup label, | |
2642 | because expand_null_return takes care of them, too. | |
2643 | Any reason why not? */ | |
2644 | if (HAVE_return && cleanup_label == 0 | |
5eb94e4e RK |
2645 | && ! current_function_returns_pcc_struct |
2646 | && BRANCH_COST <= 1) | |
28d81abb RK |
2647 | { |
2648 | /* If this is return x == y; then generate | |
2649 | if (x == y) return 1; else return 0; | |
3f8b69de TG |
2650 | if we can do it with explicit return insns and branches are cheap, |
2651 | but not if we have the corresponding scc insn. */ | |
2652 | int has_scc = 0; | |
28d81abb RK |
2653 | if (retval_rhs) |
2654 | switch (TREE_CODE (retval_rhs)) | |
2655 | { | |
2656 | case EQ_EXPR: | |
3f8b69de TG |
2657 | #ifdef HAVE_seq |
2658 | has_scc = HAVE_seq; | |
2659 | #endif | |
28d81abb | 2660 | case NE_EXPR: |
3f8b69de TG |
2661 | #ifdef HAVE_sne |
2662 | has_scc = HAVE_sne; | |
2663 | #endif | |
28d81abb | 2664 | case GT_EXPR: |
3f8b69de TG |
2665 | #ifdef HAVE_sgt |
2666 | has_scc = HAVE_sgt; | |
2667 | #endif | |
28d81abb | 2668 | case GE_EXPR: |
3f8b69de TG |
2669 | #ifdef HAVE_sge |
2670 | has_scc = HAVE_sge; | |
2671 | #endif | |
28d81abb | 2672 | case LT_EXPR: |
3f8b69de TG |
2673 | #ifdef HAVE_slt |
2674 | has_scc = HAVE_slt; | |
2675 | #endif | |
28d81abb | 2676 | case LE_EXPR: |
3f8b69de TG |
2677 | #ifdef HAVE_sle |
2678 | has_scc = HAVE_sle; | |
2679 | #endif | |
28d81abb RK |
2680 | case TRUTH_ANDIF_EXPR: |
2681 | case TRUTH_ORIF_EXPR: | |
2682 | case TRUTH_AND_EXPR: | |
2683 | case TRUTH_OR_EXPR: | |
2684 | case TRUTH_NOT_EXPR: | |
94ed3915 | 2685 | case TRUTH_XOR_EXPR: |
3f8b69de TG |
2686 | if (! has_scc) |
2687 | { | |
2688 | op0 = gen_label_rtx (); | |
2689 | jumpifnot (retval_rhs, op0); | |
2690 | expand_value_return (const1_rtx); | |
2691 | emit_label (op0); | |
2692 | expand_value_return (const0_rtx); | |
2693 | return; | |
2694 | } | |
e9a25f70 JL |
2695 | break; |
2696 | ||
2697 | default: | |
2698 | break; | |
28d81abb RK |
2699 | } |
2700 | } | |
2701 | #endif /* HAVE_return */ | |
2702 | ||
4c485b63 JL |
2703 | /* If the result is an aggregate that is being returned in one (or more) |
2704 | registers, load the registers here. The compiler currently can't handle | |
2705 | copying a BLKmode value into registers. We could put this code in a | |
2706 | more general area (for use by everyone instead of just function | |
2707 | call/return), but until this feature is generally usable it is kept here | |
3ffeb8f1 JW |
2708 | (and in expand_call). The value must go into a pseudo in case there |
2709 | are cleanups that will clobber the real return register. */ | |
4c485b63 JL |
2710 | |
2711 | if (retval_rhs != 0 | |
2712 | && TYPE_MODE (TREE_TYPE (retval_rhs)) == BLKmode | |
2713 | && GET_CODE (DECL_RTL (DECL_RESULT (current_function_decl))) == REG) | |
2714 | { | |
a7f875d7 | 2715 | int i, bitpos, xbitpos; |
4c485b63 JL |
2716 | int big_endian_correction = 0; |
2717 | int bytes = int_size_in_bytes (TREE_TYPE (retval_rhs)); | |
2718 | int n_regs = (bytes + UNITS_PER_WORD - 1) / UNITS_PER_WORD; | |
c84e2712 KG |
2719 | int bitsize = MIN (TYPE_ALIGN (TREE_TYPE (retval_rhs)), |
2720 | (unsigned int)BITS_PER_WORD); | |
4c485b63 | 2721 | rtx *result_pseudos = (rtx *) alloca (sizeof (rtx) * n_regs); |
c16ddde3 | 2722 | rtx result_reg, src = NULL_RTX, dst = NULL_RTX; |
4c485b63 | 2723 | rtx result_val = expand_expr (retval_rhs, NULL_RTX, VOIDmode, 0); |
af55da56 | 2724 | enum machine_mode tmpmode, result_reg_mode; |
4c485b63 | 2725 | |
a7f875d7 RK |
2726 | /* Structures whose size is not a multiple of a word are aligned |
2727 | to the least significant byte (to the right). On a BYTES_BIG_ENDIAN | |
2728 | machine, this means we must skip the empty high order bytes when | |
2729 | calculating the bit offset. */ | |
2730 | if (BYTES_BIG_ENDIAN && bytes % UNITS_PER_WORD) | |
2731 | big_endian_correction = (BITS_PER_WORD - ((bytes % UNITS_PER_WORD) | |
2732 | * BITS_PER_UNIT)); | |
2733 | ||
2734 | /* Copy the structure BITSIZE bits at a time. */ | |
2735 | for (bitpos = 0, xbitpos = big_endian_correction; | |
2736 | bitpos < bytes * BITS_PER_UNIT; | |
2737 | bitpos += bitsize, xbitpos += bitsize) | |
4c485b63 | 2738 | { |
a7f875d7 | 2739 | /* We need a new destination pseudo each time xbitpos is |
abc95ed3 | 2740 | on a word boundary and when xbitpos == big_endian_correction |
a7f875d7 RK |
2741 | (the first time through). */ |
2742 | if (xbitpos % BITS_PER_WORD == 0 | |
2743 | || xbitpos == big_endian_correction) | |
4c485b63 | 2744 | { |
a7f875d7 RK |
2745 | /* Generate an appropriate register. */ |
2746 | dst = gen_reg_rtx (word_mode); | |
2747 | result_pseudos[xbitpos / BITS_PER_WORD] = dst; | |
2748 | ||
2749 | /* Clobber the destination before we move anything into it. */ | |
38a448ca | 2750 | emit_insn (gen_rtx_CLOBBER (VOIDmode, dst)); |
4c485b63 | 2751 | } |
a7f875d7 RK |
2752 | |
2753 | /* We need a new source operand each time bitpos is on a word | |
2754 | boundary. */ | |
2755 | if (bitpos % BITS_PER_WORD == 0) | |
2756 | src = operand_subword_force (result_val, | |
2757 | bitpos / BITS_PER_WORD, | |
2758 | BLKmode); | |
2759 | ||
2760 | /* Use bitpos for the source extraction (left justified) and | |
2761 | xbitpos for the destination store (right justified). */ | |
2762 | store_bit_field (dst, bitsize, xbitpos % BITS_PER_WORD, word_mode, | |
2763 | extract_bit_field (src, bitsize, | |
2764 | bitpos % BITS_PER_WORD, 1, | |
2765 | NULL_RTX, word_mode, | |
2766 | word_mode, | |
2767 | bitsize / BITS_PER_UNIT, | |
2768 | BITS_PER_WORD), | |
2769 | bitsize / BITS_PER_UNIT, BITS_PER_WORD); | |
4c485b63 JL |
2770 | } |
2771 | ||
4c485b63 JL |
2772 | /* Find the smallest integer mode large enough to hold the |
2773 | entire structure and use that mode instead of BLKmode | |
2774 | on the USE insn for the return register. */ | |
2775 | bytes = int_size_in_bytes (TREE_TYPE (retval_rhs)); | |
2776 | for (tmpmode = GET_CLASS_NARROWEST_MODE (MODE_INT); | |
2777 | tmpmode != MAX_MACHINE_MODE; | |
2778 | tmpmode = GET_MODE_WIDER_MODE (tmpmode)) | |
3ffeb8f1 JW |
2779 | { |
2780 | /* Have we found a large enough mode? */ | |
2781 | if (GET_MODE_SIZE (tmpmode) >= bytes) | |
2782 | break; | |
2783 | } | |
4c485b63 JL |
2784 | |
2785 | /* No suitable mode found. */ | |
2786 | if (tmpmode == MAX_MACHINE_MODE) | |
3ffeb8f1 | 2787 | abort (); |
4c485b63 | 2788 | |
3ffeb8f1 JW |
2789 | PUT_MODE (DECL_RTL (DECL_RESULT (current_function_decl)), tmpmode); |
2790 | ||
af55da56 JW |
2791 | if (GET_MODE_SIZE (tmpmode) < GET_MODE_SIZE (word_mode)) |
2792 | result_reg_mode = word_mode; | |
2793 | else | |
2794 | result_reg_mode = tmpmode; | |
2795 | result_reg = gen_reg_rtx (result_reg_mode); | |
2796 | ||
3ffeb8f1 | 2797 | emit_queue (); |
3ffeb8f1 | 2798 | for (i = 0; i < n_regs; i++) |
af55da56 | 2799 | emit_move_insn (operand_subword (result_reg, i, 0, result_reg_mode), |
3ffeb8f1 | 2800 | result_pseudos[i]); |
4c485b63 | 2801 | |
af55da56 JW |
2802 | if (tmpmode != result_reg_mode) |
2803 | result_reg = gen_lowpart (tmpmode, result_reg); | |
2804 | ||
4c485b63 JL |
2805 | expand_value_return (result_reg); |
2806 | } | |
2807 | else if (cleanups | |
28d81abb RK |
2808 | && retval_rhs != 0 |
2809 | && TREE_TYPE (retval_rhs) != void_type_node | |
2810 | && GET_CODE (DECL_RTL (DECL_RESULT (current_function_decl))) == REG) | |
2811 | { | |
2812 | /* Calculate the return value into a pseudo reg. */ | |
dd98f85c JM |
2813 | val = gen_reg_rtx (DECL_MODE (DECL_RESULT (current_function_decl))); |
2814 | val = expand_expr (retval_rhs, val, GET_MODE (val), 0); | |
2815 | val = force_not_mem (val); | |
28d81abb | 2816 | emit_queue (); |
28d81abb RK |
2817 | /* Return the calculated value, doing cleanups first. */ |
2818 | expand_value_return (val); | |
2819 | } | |
2820 | else | |
2821 | { | |
2822 | /* No cleanups or no hard reg used; | |
2823 | calculate value into hard return reg. */ | |
cba389cd | 2824 | expand_expr (retval, const0_rtx, VOIDmode, 0); |
28d81abb | 2825 | emit_queue (); |
28d81abb RK |
2826 | expand_value_return (DECL_RTL (DECL_RESULT (current_function_decl))); |
2827 | } | |
2828 | } | |
2829 | ||
2830 | /* Return 1 if the end of the generated RTX is not a barrier. | |
2831 | This means code already compiled can drop through. */ | |
2832 | ||
2833 | int | |
2834 | drop_through_at_end_p () | |
2835 | { | |
2836 | rtx insn = get_last_insn (); | |
2837 | while (insn && GET_CODE (insn) == NOTE) | |
2838 | insn = PREV_INSN (insn); | |
2839 | return insn && GET_CODE (insn) != BARRIER; | |
2840 | } | |
2841 | \f | |
642cac7b JL |
2842 | /* Test CALL_EXPR to determine if it is a potential tail recursion call |
2843 | and emit code to optimize the tail recursion. LAST_INSN indicates where | |
564ea051 JW |
2844 | to place the jump to the tail recursion label. Return TRUE if the |
2845 | call was optimized into a goto. | |
642cac7b JL |
2846 | |
2847 | This is only used by expand_return, but expand_call is expected to | |
2848 | use it soon. */ | |
2849 | ||
564ea051 | 2850 | int |
642cac7b JL |
2851 | optimize_tail_recursion (call_expr, last_insn) |
2852 | tree call_expr; | |
2853 | rtx last_insn; | |
2854 | { | |
2855 | /* For tail-recursive call to current function, | |
2856 | just jump back to the beginning. | |
2857 | It's unsafe if any auto variable in this function | |
2858 | has its address taken; for simplicity, | |
2859 | require stack frame to be empty. */ | |
2860 | if (optimize && call_expr != 0 | |
2861 | && frame_offset == 0 | |
2862 | && TREE_CODE (call_expr) == CALL_EXPR | |
2863 | && TREE_CODE (TREE_OPERAND (call_expr, 0)) == ADDR_EXPR | |
2864 | && TREE_OPERAND (TREE_OPERAND (call_expr, 0), 0) == current_function_decl | |
2865 | /* Finish checking validity, and if valid emit code | |
2866 | to set the argument variables for the new call. */ | |
2867 | && tail_recursion_args (TREE_OPERAND (call_expr, 1), | |
2868 | DECL_ARGUMENTS (current_function_decl))) | |
2869 | { | |
2870 | if (tail_recursion_label == 0) | |
2871 | { | |
2872 | tail_recursion_label = gen_label_rtx (); | |
2873 | emit_label_after (tail_recursion_label, | |
2874 | tail_recursion_reentry); | |
2875 | } | |
2876 | emit_queue (); | |
2877 | expand_goto_internal (NULL_TREE, tail_recursion_label, last_insn); | |
2878 | emit_barrier (); | |
564ea051 | 2879 | return 1; |
642cac7b | 2880 | } |
564ea051 JW |
2881 | |
2882 | return 0; | |
642cac7b JL |
2883 | } |
2884 | ||
28d81abb RK |
2885 | /* Emit code to alter this function's formal parms for a tail-recursive call. |
2886 | ACTUALS is a list of actual parameter expressions (chain of TREE_LISTs). | |
2887 | FORMALS is the chain of decls of formals. | |
2888 | Return 1 if this can be done; | |
2889 | otherwise return 0 and do not emit any code. */ | |
2890 | ||
2891 | static int | |
2892 | tail_recursion_args (actuals, formals) | |
2893 | tree actuals, formals; | |
2894 | { | |
2895 | register tree a = actuals, f = formals; | |
2896 | register int i; | |
2897 | register rtx *argvec; | |
2898 | ||
2899 | /* Check that number and types of actuals are compatible | |
2900 | with the formals. This is not always true in valid C code. | |
2901 | Also check that no formal needs to be addressable | |
2902 | and that all formals are scalars. */ | |
2903 | ||
2904 | /* Also count the args. */ | |
2905 | ||
2906 | for (a = actuals, f = formals, i = 0; a && f; a = TREE_CHAIN (a), f = TREE_CHAIN (f), i++) | |
2907 | { | |
5c7fe359 RK |
2908 | if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_VALUE (a))) |
2909 | != TYPE_MAIN_VARIANT (TREE_TYPE (f))) | |
28d81abb RK |
2910 | return 0; |
2911 | if (GET_CODE (DECL_RTL (f)) != REG || DECL_MODE (f) == BLKmode) | |
2912 | return 0; | |
2913 | } | |
2914 | if (a != 0 || f != 0) | |
2915 | return 0; | |
2916 | ||
2917 | /* Compute all the actuals. */ | |
2918 | ||
2919 | argvec = (rtx *) alloca (i * sizeof (rtx)); | |
2920 | ||
2921 | for (a = actuals, i = 0; a; a = TREE_CHAIN (a), i++) | |
37366632 | 2922 | argvec[i] = expand_expr (TREE_VALUE (a), NULL_RTX, VOIDmode, 0); |
28d81abb RK |
2923 | |
2924 | /* Find which actual values refer to current values of previous formals. | |
2925 | Copy each of them now, before any formal is changed. */ | |
2926 | ||
2927 | for (a = actuals, i = 0; a; a = TREE_CHAIN (a), i++) | |
2928 | { | |
2929 | int copy = 0; | |
2930 | register int j; | |
2931 | for (f = formals, j = 0; j < i; f = TREE_CHAIN (f), j++) | |
2932 | if (reg_mentioned_p (DECL_RTL (f), argvec[i])) | |
2933 | { copy = 1; break; } | |
2934 | if (copy) | |
2935 | argvec[i] = copy_to_reg (argvec[i]); | |
2936 | } | |
2937 | ||
2938 | /* Store the values of the actuals into the formals. */ | |
2939 | ||
2940 | for (f = formals, a = actuals, i = 0; f; | |
2941 | f = TREE_CHAIN (f), a = TREE_CHAIN (a), i++) | |
2942 | { | |
98f3b471 | 2943 | if (GET_MODE (DECL_RTL (f)) == GET_MODE (argvec[i])) |
28d81abb RK |
2944 | emit_move_insn (DECL_RTL (f), argvec[i]); |
2945 | else | |
2946 | convert_move (DECL_RTL (f), argvec[i], | |
2947 | TREE_UNSIGNED (TREE_TYPE (TREE_VALUE (a)))); | |
2948 | } | |
2949 | ||
2950 | free_temp_slots (); | |
2951 | return 1; | |
2952 | } | |
2953 | \f | |
2954 | /* Generate the RTL code for entering a binding contour. | |
2955 | The variables are declared one by one, by calls to `expand_decl'. | |
2956 | ||
2957 | EXIT_FLAG is nonzero if this construct should be visible to | |
2958 | `exit_something'. */ | |
2959 | ||
2960 | void | |
2961 | expand_start_bindings (exit_flag) | |
2962 | int exit_flag; | |
2963 | { | |
2964 | struct nesting *thisblock = ALLOC_NESTING (); | |
b93a436e | 2965 | rtx note = emit_note (NULL_PTR, NOTE_INSN_BLOCK_BEG); |
28d81abb RK |
2966 | |
2967 | /* Make an entry on block_stack for the block we are entering. */ | |
2968 | ||
2969 | thisblock->next = block_stack; | |
2970 | thisblock->all = nesting_stack; | |
2971 | thisblock->depth = ++nesting_depth; | |
2972 | thisblock->data.block.stack_level = 0; | |
2973 | thisblock->data.block.cleanups = 0; | |
2974 | thisblock->data.block.function_call_count = 0; | |
e976b8b2 MS |
2975 | thisblock->data.block.exception_region = 0; |
2976 | thisblock->data.block.target_temp_slot_level = target_temp_slot_level; | |
2977 | ||
2978 | thisblock->data.block.conditional_code = 0; | |
2979 | thisblock->data.block.last_unconditional_cleanup = note; | |
2980 | thisblock->data.block.cleanup_ptr = &thisblock->data.block.cleanups; | |
2981 | ||
28d81abb RK |
2982 | if (block_stack |
2983 | && !(block_stack->data.block.cleanups == NULL_TREE | |
2984 | && block_stack->data.block.outer_cleanups == NULL_TREE)) | |
2985 | thisblock->data.block.outer_cleanups | |
2986 | = tree_cons (NULL_TREE, block_stack->data.block.cleanups, | |
2987 | block_stack->data.block.outer_cleanups); | |
2988 | else | |
2989 | thisblock->data.block.outer_cleanups = 0; | |
28d81abb RK |
2990 | thisblock->data.block.label_chain = 0; |
2991 | thisblock->data.block.innermost_stack_block = stack_block_stack; | |
2992 | thisblock->data.block.first_insn = note; | |
2993 | thisblock->data.block.block_start_count = ++block_start_count; | |
2994 | thisblock->exit_label = exit_flag ? gen_label_rtx () : 0; | |
2995 | block_stack = thisblock; | |
2996 | nesting_stack = thisblock; | |
2997 | ||
b93a436e JL |
2998 | /* Make a new level for allocating stack slots. */ |
2999 | push_temp_slots (); | |
28d81abb RK |
3000 | } |
3001 | ||
e976b8b2 MS |
3002 | /* Specify the scope of temporaries created by TARGET_EXPRs. Similar |
3003 | to CLEANUP_POINT_EXPR, but handles cases when a series of calls to | |
3004 | expand_expr are made. After we end the region, we know that all | |
3005 | space for all temporaries that were created by TARGET_EXPRs will be | |
3006 | destroyed and their space freed for reuse. */ | |
3007 | ||
3008 | void | |
3009 | expand_start_target_temps () | |
3010 | { | |
3011 | /* This is so that even if the result is preserved, the space | |
3012 | allocated will be freed, as we know that it is no longer in use. */ | |
3013 | push_temp_slots (); | |
3014 | ||
3015 | /* Start a new binding layer that will keep track of all cleanup | |
3016 | actions to be performed. */ | |
3017 | expand_start_bindings (0); | |
3018 | ||
3019 | target_temp_slot_level = temp_slot_level; | |
3020 | } | |
3021 | ||
3022 | void | |
3023 | expand_end_target_temps () | |
3024 | { | |
3025 | expand_end_bindings (NULL_TREE, 0, 0); | |
3026 | ||
3027 | /* This is so that even if the result is preserved, the space | |
3028 | allocated will be freed, as we know that it is no longer in use. */ | |
3029 | pop_temp_slots (); | |
3030 | } | |
3031 | ||
3032 | /* Mark top block of block_stack as an implicit binding for an | |
3033 | exception region. This is used to prevent infinite recursion when | |
3034 | ending a binding with expand_end_bindings. It is only ever called | |
3035 | by expand_eh_region_start, as that it the only way to create a | |
3036 | block stack for a exception region. */ | |
3037 | ||
3038 | void | |
3039 | mark_block_as_eh_region () | |
3040 | { | |
3041 | block_stack->data.block.exception_region = 1; | |
3042 | if (block_stack->next | |
3043 | && block_stack->next->data.block.conditional_code) | |
3044 | { | |
3045 | block_stack->data.block.conditional_code | |
3046 | = block_stack->next->data.block.conditional_code; | |
3047 | block_stack->data.block.last_unconditional_cleanup | |
3048 | = block_stack->next->data.block.last_unconditional_cleanup; | |
3049 | block_stack->data.block.cleanup_ptr | |
3050 | = block_stack->next->data.block.cleanup_ptr; | |
3051 | } | |
3052 | } | |
3053 | ||
3054 | /* True if we are currently emitting insns in an area of output code | |
3055 | that is controlled by a conditional expression. This is used by | |
3056 | the cleanup handling code to generate conditional cleanup actions. */ | |
3057 | ||
3058 | int | |
3059 | conditional_context () | |
3060 | { | |
3061 | return block_stack && block_stack->data.block.conditional_code; | |
3062 | } | |
3063 | ||
3064 | /* Mark top block of block_stack as not for an implicit binding for an | |
3065 | exception region. This is only ever done by expand_eh_region_end | |
3066 | to let expand_end_bindings know that it is being called explicitly | |
3067 | to end the binding layer for just the binding layer associated with | |
3068 | the exception region, otherwise expand_end_bindings would try and | |
3069 | end all implicit binding layers for exceptions regions, and then | |
3070 | one normal binding layer. */ | |
3071 | ||
3072 | void | |
3073 | mark_block_as_not_eh_region () | |
3074 | { | |
3075 | block_stack->data.block.exception_region = 0; | |
3076 | } | |
3077 | ||
3078 | /* True if the top block of block_stack was marked as for an exception | |
3079 | region by mark_block_as_eh_region. */ | |
3080 | ||
3081 | int | |
3082 | is_eh_region () | |
3083 | { | |
3084 | return block_stack && block_stack->data.block.exception_region; | |
3085 | } | |
3086 | ||
7629c936 RS |
3087 | /* Given a pointer to a BLOCK node, save a pointer to the most recently |
3088 | generated NOTE_INSN_BLOCK_END in the BLOCK_END_NOTE field of the given | |
3089 | BLOCK node. */ | |
3090 | ||
3091 | void | |
3092 | remember_end_note (block) | |
3093 | register tree block; | |
3094 | { | |
3095 | BLOCK_END_NOTE (block) = last_block_end_note; | |
3096 | last_block_end_note = NULL_RTX; | |
3097 | } | |
3098 | ||
ba716ac9 BS |
3099 | /* Emit a handler label for a nonlocal goto handler. |
3100 | Also emit code to store the handler label in SLOT before BEFORE_INSN. */ | |
3101 | ||
3102 | static void | |
3103 | expand_nl_handler_label (slot, before_insn) | |
3104 | rtx slot, before_insn; | |
3105 | { | |
3106 | rtx insns; | |
3107 | rtx handler_label = gen_label_rtx (); | |
3108 | ||
3109 | /* Don't let jump_optimize delete the handler. */ | |
3110 | LABEL_PRESERVE_P (handler_label) = 1; | |
3111 | ||
3112 | start_sequence (); | |
3113 | emit_move_insn (slot, gen_rtx_LABEL_REF (Pmode, handler_label)); | |
3114 | insns = get_insns (); | |
3115 | end_sequence (); | |
3116 | emit_insns_before (insns, before_insn); | |
3117 | ||
3118 | emit_label (handler_label); | |
3119 | } | |
3120 | ||
3121 | /* Emit code to restore vital registers at the beginning of a nonlocal goto | |
3122 | handler. */ | |
3123 | static void | |
3124 | expand_nl_goto_receiver () | |
3125 | { | |
3126 | #ifdef HAVE_nonlocal_goto | |
3127 | if (! HAVE_nonlocal_goto) | |
3128 | #endif | |
3129 | /* First adjust our frame pointer to its actual value. It was | |
3130 | previously set to the start of the virtual area corresponding to | |
3131 | the stacked variables when we branched here and now needs to be | |
3132 | adjusted to the actual hardware fp value. | |
3133 | ||
3134 | Assignments are to virtual registers are converted by | |
3135 | instantiate_virtual_regs into the corresponding assignment | |
3136 | to the underlying register (fp in this case) that makes | |
3137 | the original assignment true. | |
3138 | So the following insn will actually be | |
3139 | decrementing fp by STARTING_FRAME_OFFSET. */ | |
3140 | emit_move_insn (virtual_stack_vars_rtx, hard_frame_pointer_rtx); | |
3141 | ||
3142 | #if ARG_POINTER_REGNUM != HARD_FRAME_POINTER_REGNUM | |
3143 | if (fixed_regs[ARG_POINTER_REGNUM]) | |
3144 | { | |
3145 | #ifdef ELIMINABLE_REGS | |
3146 | /* If the argument pointer can be eliminated in favor of the | |
3147 | frame pointer, we don't need to restore it. We assume here | |
3148 | that if such an elimination is present, it can always be used. | |
3149 | This is the case on all known machines; if we don't make this | |
3150 | assumption, we do unnecessary saving on many machines. */ | |
3151 | static struct elims {int from, to;} elim_regs[] = ELIMINABLE_REGS; | |
3152 | size_t i; | |
3153 | ||
3154 | for (i = 0; i < sizeof elim_regs / sizeof elim_regs[0]; i++) | |
3155 | if (elim_regs[i].from == ARG_POINTER_REGNUM | |
3156 | && elim_regs[i].to == HARD_FRAME_POINTER_REGNUM) | |
3157 | break; | |
3158 | ||
3159 | if (i == sizeof elim_regs / sizeof elim_regs [0]) | |
3160 | #endif | |
3161 | { | |
3162 | /* Now restore our arg pointer from the address at which it | |
3163 | was saved in our stack frame. | |
3164 | If there hasn't be space allocated for it yet, make | |
3165 | some now. */ | |
3166 | if (arg_pointer_save_area == 0) | |
3167 | arg_pointer_save_area | |
3168 | = assign_stack_local (Pmode, GET_MODE_SIZE (Pmode), 0); | |
3169 | emit_move_insn (virtual_incoming_args_rtx, | |
3170 | /* We need a pseudo here, or else | |
3171 | instantiate_virtual_regs_1 complains. */ | |
3172 | copy_to_reg (arg_pointer_save_area)); | |
3173 | } | |
3174 | } | |
3175 | #endif | |
3176 | ||
3177 | #ifdef HAVE_nonlocal_goto_receiver | |
3178 | if (HAVE_nonlocal_goto_receiver) | |
3179 | emit_insn (gen_nonlocal_goto_receiver ()); | |
3180 | #endif | |
3181 | } | |
3182 | ||
3183 | /* Make handlers for nonlocal gotos taking place in the function calls in | |
3184 | block THISBLOCK. */ | |
3185 | ||
3186 | static void | |
3187 | expand_nl_goto_receivers (thisblock) | |
3188 | struct nesting *thisblock; | |
3189 | { | |
3190 | tree link; | |
3191 | rtx afterward = gen_label_rtx (); | |
3192 | rtx insns, slot; | |
3193 | int any_invalid; | |
3194 | ||
3195 | /* Record the handler address in the stack slot for that purpose, | |
3196 | during this block, saving and restoring the outer value. */ | |
3197 | if (thisblock->next != 0) | |
3198 | for (slot = nonlocal_goto_handler_slots; slot; slot = XEXP (slot, 1)) | |
3199 | { | |
3200 | rtx save_receiver = gen_reg_rtx (Pmode); | |
3201 | emit_move_insn (XEXP (slot, 0), save_receiver); | |
3202 | ||
3203 | start_sequence (); | |
3204 | emit_move_insn (save_receiver, XEXP (slot, 0)); | |
3205 | insns = get_insns (); | |
3206 | end_sequence (); | |
3207 | emit_insns_before (insns, thisblock->data.block.first_insn); | |
3208 | } | |
3209 | ||
3210 | /* Jump around the handlers; they run only when specially invoked. */ | |
3211 | emit_jump (afterward); | |
3212 | ||
3213 | /* Make a separate handler for each label. */ | |
3214 | link = nonlocal_labels; | |
3215 | slot = nonlocal_goto_handler_slots; | |
3216 | for (; link; link = TREE_CHAIN (link), slot = XEXP (slot, 1)) | |
3217 | /* Skip any labels we shouldn't be able to jump to from here, | |
3218 | we generate one special handler for all of them below which just calls | |
3219 | abort. */ | |
3220 | if (! DECL_TOO_LATE (TREE_VALUE (link))) | |
3221 | { | |
3222 | expand_nl_handler_label (XEXP (slot, 0), | |
3223 | thisblock->data.block.first_insn); | |
3224 | expand_nl_goto_receiver (); | |
3225 | ||
3226 | /* Jump to the "real" nonlocal label. */ | |
3227 | expand_goto (TREE_VALUE (link)); | |
3228 | } | |
3229 | ||
3230 | /* A second pass over all nonlocal labels; this time we handle those | |
3231 | we should not be able to jump to at this point. */ | |
3232 | link = nonlocal_labels; | |
3233 | slot = nonlocal_goto_handler_slots; | |
3234 | any_invalid = 0; | |
3235 | for (; link; link = TREE_CHAIN (link), slot = XEXP (slot, 1)) | |
3236 | if (DECL_TOO_LATE (TREE_VALUE (link))) | |
3237 | { | |
3238 | expand_nl_handler_label (XEXP (slot, 0), | |
3239 | thisblock->data.block.first_insn); | |
3240 | any_invalid = 1; | |
3241 | } | |
3242 | ||
3243 | if (any_invalid) | |
3244 | { | |
3245 | expand_nl_goto_receiver (); | |
3246 | emit_library_call (gen_rtx_SYMBOL_REF (Pmode, "abort"), 0, | |
3247 | VOIDmode, 0); | |
3248 | emit_barrier (); | |
3249 | } | |
3250 | ||
3251 | emit_label (afterward); | |
3252 | } | |
3253 | ||
28d81abb RK |
3254 | /* Generate RTL code to terminate a binding contour. |
3255 | VARS is the chain of VAR_DECL nodes | |
3256 | for the variables bound in this contour. | |
3257 | MARK_ENDS is nonzero if we should put a note at the beginning | |
3258 | and end of this binding contour. | |
3259 | ||
3260 | DONT_JUMP_IN is nonzero if it is not valid to jump into this contour. | |
3261 | (That is true automatically if the contour has a saved stack level.) */ | |
3262 | ||
3263 | void | |
3264 | expand_end_bindings (vars, mark_ends, dont_jump_in) | |
3265 | tree vars; | |
3266 | int mark_ends; | |
3267 | int dont_jump_in; | |
3268 | { | |
e976b8b2 | 3269 | register struct nesting *thisblock; |
28d81abb RK |
3270 | register tree decl; |
3271 | ||
e976b8b2 MS |
3272 | while (block_stack->data.block.exception_region) |
3273 | { | |
3274 | /* Because we don't need or want a new temporary level and | |
3275 | because we didn't create one in expand_eh_region_start, | |
3276 | create a fake one now to avoid removing one in | |
3277 | expand_end_bindings. */ | |
3278 | push_temp_slots (); | |
3279 | ||
3280 | block_stack->data.block.exception_region = 0; | |
3281 | ||
3282 | expand_end_bindings (NULL_TREE, 0, 0); | |
3283 | } | |
3284 | ||
e976b8b2 MS |
3285 | /* Since expand_eh_region_start does an expand_start_bindings, we |
3286 | have to first end all the bindings that were created by | |
3287 | expand_eh_region_start. */ | |
3288 | ||
3289 | thisblock = block_stack; | |
3290 | ||
28d81abb RK |
3291 | if (warn_unused) |
3292 | for (decl = vars; decl; decl = TREE_CHAIN (decl)) | |
7e70e7c5 | 3293 | if (! TREE_USED (decl) && TREE_CODE (decl) == VAR_DECL |
e9a25f70 JL |
3294 | && ! DECL_IN_SYSTEM_HEADER (decl) |
3295 | && DECL_NAME (decl) && ! DECL_ARTIFICIAL (decl)) | |
28d81abb RK |
3296 | warning_with_decl (decl, "unused variable `%s'"); |
3297 | ||
28d81abb RK |
3298 | if (thisblock->exit_label) |
3299 | { | |
3300 | do_pending_stack_adjust (); | |
3301 | emit_label (thisblock->exit_label); | |
3302 | } | |
3303 | ||
ba716ac9 | 3304 | /* If necessary, make handlers for nonlocal gotos taking |
28d81abb RK |
3305 | place in the function calls in this block. */ |
3306 | if (function_call_count != thisblock->data.block.function_call_count | |
3307 | && nonlocal_labels | |
3308 | /* Make handler for outermost block | |
3309 | if there were any nonlocal gotos to this function. */ | |
3310 | && (thisblock->next == 0 ? current_function_has_nonlocal_label | |
3311 | /* Make handler for inner block if it has something | |
3312 | special to do when you jump out of it. */ | |
3313 | : (thisblock->data.block.cleanups != 0 | |
3314 | || thisblock->data.block.stack_level != 0))) | |
ba716ac9 | 3315 | expand_nl_goto_receivers (thisblock); |
28d81abb | 3316 | |
72eb1038 BH |
3317 | /* Don't allow jumping into a block that has a stack level. |
3318 | Cleanups are allowed, though. */ | |
28d81abb | 3319 | if (dont_jump_in |
72eb1038 | 3320 | || thisblock->data.block.stack_level != 0) |
28d81abb RK |
3321 | { |
3322 | struct label_chain *chain; | |
3323 | ||
3324 | /* Any labels in this block are no longer valid to go to. | |
3325 | Mark them to cause an error message. */ | |
3326 | for (chain = thisblock->data.block.label_chain; chain; chain = chain->next) | |
3327 | { | |
3328 | DECL_TOO_LATE (chain->label) = 1; | |
3329 | /* If any goto without a fixup came to this label, | |
3330 | that must be an error, because gotos without fixups | |
72eb1038 | 3331 | come from outside all saved stack-levels. */ |
28d81abb RK |
3332 | if (TREE_ADDRESSABLE (chain->label)) |
3333 | error_with_decl (chain->label, | |
3334 | "label `%s' used before containing binding contour"); | |
3335 | } | |
3336 | } | |
3337 | ||
3338 | /* Restore stack level in effect before the block | |
3339 | (only if variable-size objects allocated). */ | |
3340 | /* Perform any cleanups associated with the block. */ | |
3341 | ||
3342 | if (thisblock->data.block.stack_level != 0 | |
3343 | || thisblock->data.block.cleanups != 0) | |
3344 | { | |
413ec213 | 3345 | /* Only clean up here if this point can actually be reached. */ |
50d1b7a1 | 3346 | int reachable = GET_CODE (get_last_insn ()) != BARRIER; |
28d81abb | 3347 | |
50d1b7a1 MS |
3348 | /* Don't let cleanups affect ({...}) constructs. */ |
3349 | int old_expr_stmts_for_value = expr_stmts_for_value; | |
3350 | rtx old_last_expr_value = last_expr_value; | |
3351 | tree old_last_expr_type = last_expr_type; | |
3352 | expr_stmts_for_value = 0; | |
28d81abb | 3353 | |
50d1b7a1 MS |
3354 | /* Do the cleanups. */ |
3355 | expand_cleanups (thisblock->data.block.cleanups, NULL_TREE, 0, reachable); | |
3356 | if (reachable) | |
3357 | do_pending_stack_adjust (); | |
28d81abb | 3358 | |
50d1b7a1 MS |
3359 | expr_stmts_for_value = old_expr_stmts_for_value; |
3360 | last_expr_value = old_last_expr_value; | |
3361 | last_expr_type = old_last_expr_type; | |
3362 | ||
3363 | /* Restore the stack level. */ | |
3364 | ||
3365 | if (reachable && thisblock->data.block.stack_level != 0) | |
3366 | { | |
3367 | emit_stack_restore (thisblock->next ? SAVE_BLOCK : SAVE_FUNCTION, | |
3368 | thisblock->data.block.stack_level, NULL_RTX); | |
ba716ac9 | 3369 | if (nonlocal_goto_handler_slots != 0) |
50d1b7a1 MS |
3370 | emit_stack_save (SAVE_NONLOCAL, &nonlocal_goto_stack_level, |
3371 | NULL_RTX); | |
28d81abb RK |
3372 | } |
3373 | ||
3374 | /* Any gotos out of this block must also do these things. | |
59257ff7 RK |
3375 | Also report any gotos with fixups that came to labels in this |
3376 | level. */ | |
28d81abb RK |
3377 | fixup_gotos (thisblock, |
3378 | thisblock->data.block.stack_level, | |
3379 | thisblock->data.block.cleanups, | |
3380 | thisblock->data.block.first_insn, | |
3381 | dont_jump_in); | |
3382 | } | |
3383 | ||
c7d2d61d RS |
3384 | /* Mark the beginning and end of the scope if requested. |
3385 | We do this now, after running cleanups on the variables | |
3386 | just going out of scope, so they are in scope for their cleanups. */ | |
3387 | ||
3388 | if (mark_ends) | |
7629c936 | 3389 | last_block_end_note = emit_note (NULL_PTR, NOTE_INSN_BLOCK_END); |
c7d2d61d RS |
3390 | else |
3391 | /* Get rid of the beginning-mark if we don't make an end-mark. */ | |
3392 | NOTE_LINE_NUMBER (thisblock->data.block.first_insn) = NOTE_INSN_DELETED; | |
3393 | ||
28d81abb RK |
3394 | /* If doing stupid register allocation, make sure lives of all |
3395 | register variables declared here extend thru end of scope. */ | |
3396 | ||
3397 | if (obey_regdecls) | |
3398 | for (decl = vars; decl; decl = TREE_CHAIN (decl)) | |
3399 | { | |
3400 | rtx rtl = DECL_RTL (decl); | |
3401 | if (TREE_CODE (decl) == VAR_DECL && rtl != 0) | |
3402 | use_variable (rtl); | |
3403 | } | |
3404 | ||
e976b8b2 MS |
3405 | /* Restore the temporary level of TARGET_EXPRs. */ |
3406 | target_temp_slot_level = thisblock->data.block.target_temp_slot_level; | |
3407 | ||
28d81abb RK |
3408 | /* Restore block_stack level for containing block. */ |
3409 | ||
3410 | stack_block_stack = thisblock->data.block.innermost_stack_block; | |
3411 | POPSTACK (block_stack); | |
3412 | ||
3413 | /* Pop the stack slot nesting and free any slots at this level. */ | |
3414 | pop_temp_slots (); | |
3415 | } | |
3416 | \f | |
3417 | /* Generate RTL for the automatic variable declaration DECL. | |
ec5cd386 | 3418 | (Other kinds of declarations are simply ignored if seen here.) */ |
28d81abb RK |
3419 | |
3420 | void | |
3421 | expand_decl (decl) | |
3422 | register tree decl; | |
3423 | { | |
3424 | struct nesting *thisblock = block_stack; | |
ca695ac9 JB |
3425 | tree type; |
3426 | ||
ca695ac9 | 3427 | type = TREE_TYPE (decl); |
28d81abb RK |
3428 | |
3429 | /* Only automatic variables need any expansion done. | |
3430 | Static and external variables, and external functions, | |
3431 | will be handled by `assemble_variable' (called from finish_decl). | |
3432 | TYPE_DECL and CONST_DECL require nothing. | |
3433 | PARM_DECLs are handled in `assign_parms'. */ | |
3434 | ||
3435 | if (TREE_CODE (decl) != VAR_DECL) | |
3436 | return; | |
44fe2e80 | 3437 | if (TREE_STATIC (decl) || DECL_EXTERNAL (decl)) |
28d81abb RK |
3438 | return; |
3439 | ||
3440 | /* Create the RTL representation for the variable. */ | |
3441 | ||
3442 | if (type == error_mark_node) | |
38a448ca | 3443 | DECL_RTL (decl) = gen_rtx_MEM (BLKmode, const0_rtx); |
28d81abb RK |
3444 | else if (DECL_SIZE (decl) == 0) |
3445 | /* Variable with incomplete type. */ | |
3446 | { | |
3447 | if (DECL_INITIAL (decl) == 0) | |
3448 | /* Error message was already done; now avoid a crash. */ | |
3449 | DECL_RTL (decl) = assign_stack_temp (DECL_MODE (decl), 0, 1); | |
3450 | else | |
3451 | /* An initializer is going to decide the size of this array. | |
3452 | Until we know the size, represent its address with a reg. */ | |
38a448ca | 3453 | DECL_RTL (decl) = gen_rtx_MEM (BLKmode, gen_reg_rtx (Pmode)); |
c6df88cb | 3454 | MEM_SET_IN_STRUCT_P (DECL_RTL (decl), AGGREGATE_TYPE_P (type)); |
28d81abb RK |
3455 | } |
3456 | else if (DECL_MODE (decl) != BLKmode | |
3457 | /* If -ffloat-store, don't put explicit float vars | |
3458 | into regs. */ | |
3459 | && !(flag_float_store | |
3460 | && TREE_CODE (type) == REAL_TYPE) | |
3461 | && ! TREE_THIS_VOLATILE (decl) | |
3462 | && ! TREE_ADDRESSABLE (decl) | |
e5e809f4 JL |
3463 | && (DECL_REGISTER (decl) || ! obey_regdecls) |
3464 | /* if -fcheck-memory-usage, check all variables. */ | |
7d384cc0 | 3465 | && ! current_function_check_memory_usage) |
28d81abb RK |
3466 | { |
3467 | /* Automatic variable that can go in a register. */ | |
98f3b471 | 3468 | int unsignedp = TREE_UNSIGNED (type); |
28612f9e RK |
3469 | enum machine_mode reg_mode |
3470 | = promote_mode (type, DECL_MODE (decl), &unsignedp, 0); | |
98f3b471 | 3471 | |
7f070d5e RK |
3472 | DECL_RTL (decl) = gen_reg_rtx (reg_mode); |
3473 | mark_user_reg (DECL_RTL (decl)); | |
3474 | ||
e5e809f4 | 3475 | if (POINTER_TYPE_P (type)) |
7f070d5e RK |
3476 | mark_reg_pointer (DECL_RTL (decl), |
3477 | (TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl))) | |
3478 | / BITS_PER_UNIT)); | |
28d81abb | 3479 | } |
0df15c2c | 3480 | |
5e4ef18a RK |
3481 | else if (TREE_CODE (DECL_SIZE (decl)) == INTEGER_CST |
3482 | && ! (flag_stack_check && ! STACK_CHECK_BUILTIN | |
3483 | && (TREE_INT_CST_HIGH (DECL_SIZE (decl)) != 0 | |
3484 | || (TREE_INT_CST_LOW (DECL_SIZE (decl)) | |
3485 | > STACK_CHECK_MAX_VAR_SIZE * BITS_PER_UNIT)))) | |
28d81abb RK |
3486 | { |
3487 | /* Variable of fixed size that goes on the stack. */ | |
3488 | rtx oldaddr = 0; | |
3489 | rtx addr; | |
3490 | ||
3491 | /* If we previously made RTL for this decl, it must be an array | |
3492 | whose size was determined by the initializer. | |
3493 | The old address was a register; set that register now | |
3494 | to the proper address. */ | |
3495 | if (DECL_RTL (decl) != 0) | |
3496 | { | |
3497 | if (GET_CODE (DECL_RTL (decl)) != MEM | |
3498 | || GET_CODE (XEXP (DECL_RTL (decl), 0)) != REG) | |
3499 | abort (); | |
3500 | oldaddr = XEXP (DECL_RTL (decl), 0); | |
3501 | } | |
3502 | ||
d16790f2 | 3503 | DECL_RTL (decl) = assign_temp (TREE_TYPE (decl), 1, 1, 1); |
c6df88cb MM |
3504 | MEM_SET_IN_STRUCT_P (DECL_RTL (decl), |
3505 | AGGREGATE_TYPE_P (TREE_TYPE (decl))); | |
28d81abb RK |
3506 | |
3507 | /* Set alignment we actually gave this decl. */ | |
3508 | DECL_ALIGN (decl) = (DECL_MODE (decl) == BLKmode ? BIGGEST_ALIGNMENT | |
3509 | : GET_MODE_BITSIZE (DECL_MODE (decl))); | |
3510 | ||
3511 | if (oldaddr) | |
3512 | { | |
3513 | addr = force_operand (XEXP (DECL_RTL (decl), 0), oldaddr); | |
3514 | if (addr != oldaddr) | |
3515 | emit_move_insn (oldaddr, addr); | |
3516 | } | |
3517 | ||
3518 | /* If this is a memory ref that contains aggregate components, | |
3519 | mark it as such for cse and loop optimize. */ | |
c6df88cb MM |
3520 | MEM_SET_IN_STRUCT_P (DECL_RTL (decl), |
3521 | AGGREGATE_TYPE_P (TREE_TYPE (decl))); | |
28d81abb RK |
3522 | #if 0 |
3523 | /* If this is in memory because of -ffloat-store, | |
3524 | set the volatile bit, to prevent optimizations from | |
3525 | undoing the effects. */ | |
3526 | if (flag_float_store && TREE_CODE (type) == REAL_TYPE) | |
3527 | MEM_VOLATILE_P (DECL_RTL (decl)) = 1; | |
3528 | #endif | |
41472af8 MM |
3529 | |
3530 | MEM_ALIAS_SET (DECL_RTL (decl)) = get_alias_set (decl); | |
28d81abb RK |
3531 | } |
3532 | else | |
3533 | /* Dynamic-size object: must push space on the stack. */ | |
3534 | { | |
3535 | rtx address, size; | |
3536 | ||
3537 | /* Record the stack pointer on entry to block, if have | |
3538 | not already done so. */ | |
3539 | if (thisblock->data.block.stack_level == 0) | |
3540 | { | |
3541 | do_pending_stack_adjust (); | |
59257ff7 RK |
3542 | emit_stack_save (thisblock->next ? SAVE_BLOCK : SAVE_FUNCTION, |
3543 | &thisblock->data.block.stack_level, | |
3544 | thisblock->data.block.first_insn); | |
28d81abb RK |
3545 | stack_block_stack = thisblock; |
3546 | } | |
3547 | ||
3548 | /* Compute the variable's size, in bytes. */ | |
3549 | size = expand_expr (size_binop (CEIL_DIV_EXPR, | |
3550 | DECL_SIZE (decl), | |
3551 | size_int (BITS_PER_UNIT)), | |
37366632 | 3552 | NULL_RTX, VOIDmode, 0); |
28d81abb RK |
3553 | free_temp_slots (); |
3554 | ||
ff91ad08 RK |
3555 | /* Allocate space on the stack for the variable. Note that |
3556 | DECL_ALIGN says how the variable is to be aligned and we | |
3557 | cannot use it to conclude anything about the alignment of | |
3558 | the size. */ | |
37366632 | 3559 | address = allocate_dynamic_stack_space (size, NULL_RTX, |
ff91ad08 | 3560 | TYPE_ALIGN (TREE_TYPE (decl))); |
28d81abb | 3561 | |
28d81abb | 3562 | /* Reference the variable indirect through that rtx. */ |
38a448ca | 3563 | DECL_RTL (decl) = gen_rtx_MEM (DECL_MODE (decl), address); |
28d81abb | 3564 | |
2207e295 RS |
3565 | /* If this is a memory ref that contains aggregate components, |
3566 | mark it as such for cse and loop optimize. */ | |
c6df88cb MM |
3567 | MEM_SET_IN_STRUCT_P (DECL_RTL (decl), |
3568 | AGGREGATE_TYPE_P (TREE_TYPE (decl))); | |
2207e295 | 3569 | |
28d81abb RK |
3570 | /* Indicate the alignment we actually gave this variable. */ |
3571 | #ifdef STACK_BOUNDARY | |
3572 | DECL_ALIGN (decl) = STACK_BOUNDARY; | |
3573 | #else | |
3574 | DECL_ALIGN (decl) = BIGGEST_ALIGNMENT; | |
3575 | #endif | |
3576 | } | |
3577 | ||
3578 | if (TREE_THIS_VOLATILE (decl)) | |
3579 | MEM_VOLATILE_P (DECL_RTL (decl)) = 1; | |
b4bf13a8 RS |
3580 | #if 0 /* A variable is not necessarily unchanging |
3581 | just because it is const. RTX_UNCHANGING_P | |
3582 | means no change in the function, | |
3583 | not merely no change in the variable's scope. | |
3584 | It is correct to set RTX_UNCHANGING_P if the variable's scope | |
3585 | is the whole function. There's no convenient way to test that. */ | |
28d81abb RK |
3586 | if (TREE_READONLY (decl)) |
3587 | RTX_UNCHANGING_P (DECL_RTL (decl)) = 1; | |
b4bf13a8 | 3588 | #endif |
28d81abb RK |
3589 | |
3590 | /* If doing stupid register allocation, make sure life of any | |
3591 | register variable starts here, at the start of its scope. */ | |
3592 | ||
3593 | if (obey_regdecls) | |
3594 | use_variable (DECL_RTL (decl)); | |
3595 | } | |
ca695ac9 JB |
3596 | |
3597 | ||
28d81abb RK |
3598 | \f |
3599 | /* Emit code to perform the initialization of a declaration DECL. */ | |
3600 | ||
3601 | void | |
3602 | expand_decl_init (decl) | |
3603 | tree decl; | |
3604 | { | |
b4ac57ab RS |
3605 | int was_used = TREE_USED (decl); |
3606 | ||
3564e40e RK |
3607 | /* If this is a CONST_DECL, we don't have to generate any code, but |
3608 | if DECL_INITIAL is a constant, call expand_expr to force TREE_CST_RTL | |
3609 | to be set while in the obstack containing the constant. If we don't | |
3610 | do this, we can lose if we have functions nested three deep and the middle | |
3611 | function makes a CONST_DECL whose DECL_INITIAL is a STRING_CST while | |
3612 | the innermost function is the first to expand that STRING_CST. */ | |
3613 | if (TREE_CODE (decl) == CONST_DECL) | |
3614 | { | |
3615 | if (DECL_INITIAL (decl) && TREE_CONSTANT (DECL_INITIAL (decl))) | |
3616 | expand_expr (DECL_INITIAL (decl), NULL_RTX, VOIDmode, | |
3617 | EXPAND_INITIALIZER); | |
3618 | return; | |
3619 | } | |
3620 | ||
28d81abb RK |
3621 | if (TREE_STATIC (decl)) |
3622 | return; | |
3623 | ||
3624 | /* Compute and store the initial value now. */ | |
3625 | ||
3626 | if (DECL_INITIAL (decl) == error_mark_node) | |
3627 | { | |
3628 | enum tree_code code = TREE_CODE (TREE_TYPE (decl)); | |
e5e809f4 | 3629 | |
28d81abb | 3630 | if (code == INTEGER_TYPE || code == REAL_TYPE || code == ENUMERAL_TYPE |
e5e809f4 | 3631 | || code == POINTER_TYPE || code == REFERENCE_TYPE) |
28d81abb RK |
3632 | expand_assignment (decl, convert (TREE_TYPE (decl), integer_zero_node), |
3633 | 0, 0); | |
3634 | emit_queue (); | |
3635 | } | |
3636 | else if (DECL_INITIAL (decl) && TREE_CODE (DECL_INITIAL (decl)) != TREE_LIST) | |
3637 | { | |
3638 | emit_line_note (DECL_SOURCE_FILE (decl), DECL_SOURCE_LINE (decl)); | |
3639 | expand_assignment (decl, DECL_INITIAL (decl), 0, 0); | |
3640 | emit_queue (); | |
3641 | } | |
3642 | ||
b4ac57ab RS |
3643 | /* Don't let the initialization count as "using" the variable. */ |
3644 | TREE_USED (decl) = was_used; | |
3645 | ||
28d81abb | 3646 | /* Free any temporaries we made while initializing the decl. */ |
ae8c59c0 | 3647 | preserve_temp_slots (NULL_RTX); |
28d81abb RK |
3648 | free_temp_slots (); |
3649 | } | |
3650 | ||
3651 | /* CLEANUP is an expression to be executed at exit from this binding contour; | |
3652 | for example, in C++, it might call the destructor for this variable. | |
3653 | ||
4847c938 MS |
3654 | We wrap CLEANUP in an UNSAVE_EXPR node, so that we can expand the |
3655 | CLEANUP multiple times, and have the correct semantics. This | |
e976b8b2 MS |
3656 | happens in exception handling, for gotos, returns, breaks that |
3657 | leave the current scope. | |
28d81abb RK |
3658 | |
3659 | If CLEANUP is nonzero and DECL is zero, we record a cleanup | |
3660 | that is not associated with any particular variable. */ | |
3661 | ||
3662 | int | |
3663 | expand_decl_cleanup (decl, cleanup) | |
3664 | tree decl, cleanup; | |
3665 | { | |
3666 | struct nesting *thisblock = block_stack; | |
3667 | ||
3668 | /* Error if we are not in any block. */ | |
3669 | if (thisblock == 0) | |
3670 | return 0; | |
3671 | ||
3672 | /* Record the cleanup if there is one. */ | |
3673 | ||
3674 | if (cleanup != 0) | |
3675 | { | |
e976b8b2 MS |
3676 | tree t; |
3677 | rtx seq; | |
3678 | tree *cleanups = &thisblock->data.block.cleanups; | |
3679 | int cond_context = conditional_context (); | |
3680 | ||
3681 | if (cond_context) | |
3682 | { | |
3683 | rtx flag = gen_reg_rtx (word_mode); | |
3684 | rtx set_flag_0; | |
3685 | tree cond; | |
3686 | ||
3687 | start_sequence (); | |
3688 | emit_move_insn (flag, const0_rtx); | |
3689 | set_flag_0 = get_insns (); | |
3690 | end_sequence (); | |
3691 | ||
3692 | thisblock->data.block.last_unconditional_cleanup | |
3693 | = emit_insns_after (set_flag_0, | |
3694 | thisblock->data.block.last_unconditional_cleanup); | |
3695 | ||
3696 | emit_move_insn (flag, const1_rtx); | |
3697 | ||
3698 | /* All cleanups must be on the function_obstack. */ | |
3699 | push_obstacks_nochange (); | |
3700 | resume_temporary_allocation (); | |
3701 | ||
3702 | cond = build_decl (VAR_DECL, NULL_TREE, type_for_mode (word_mode, 1)); | |
3703 | DECL_RTL (cond) = flag; | |
3704 | ||
3705 | /* Conditionalize the cleanup. */ | |
3706 | cleanup = build (COND_EXPR, void_type_node, | |
3707 | truthvalue_conversion (cond), | |
3708 | cleanup, integer_zero_node); | |
3709 | cleanup = fold (cleanup); | |
3710 | ||
3711 | pop_obstacks (); | |
3712 | ||
3713 | cleanups = thisblock->data.block.cleanup_ptr; | |
3714 | } | |
3715 | ||
3716 | /* All cleanups must be on the function_obstack. */ | |
3717 | push_obstacks_nochange (); | |
3718 | resume_temporary_allocation (); | |
4847c938 | 3719 | cleanup = unsave_expr (cleanup); |
e976b8b2 MS |
3720 | pop_obstacks (); |
3721 | ||
3722 | t = *cleanups = temp_tree_cons (decl, cleanup, *cleanups); | |
3723 | ||
3724 | if (! cond_context) | |
3725 | /* If this block has a cleanup, it belongs in stack_block_stack. */ | |
3726 | stack_block_stack = thisblock; | |
3727 | ||
3728 | if (cond_context) | |
3729 | { | |
3730 | start_sequence (); | |
3731 | } | |
4847c938 | 3732 | |
e976b8b2 MS |
3733 | /* If this was optimized so that there is no exception region for the |
3734 | cleanup, then mark the TREE_LIST node, so that we can later tell | |
3735 | if we need to call expand_eh_region_end. */ | |
e9a25f70 JL |
3736 | if (! using_eh_for_cleanups_p |
3737 | || expand_eh_region_start_tree (decl, cleanup)) | |
e976b8b2 | 3738 | TREE_ADDRESSABLE (t) = 1; |
716cc7f7 JM |
3739 | /* If that started a new EH region, we're in a new block. */ |
3740 | thisblock = block_stack; | |
e976b8b2 MS |
3741 | |
3742 | if (cond_context) | |
3743 | { | |
3744 | seq = get_insns (); | |
3745 | end_sequence (); | |
7e82801f MS |
3746 | if (seq) |
3747 | thisblock->data.block.last_unconditional_cleanup | |
3748 | = emit_insns_after (seq, | |
3749 | thisblock->data.block.last_unconditional_cleanup); | |
e976b8b2 MS |
3750 | } |
3751 | else | |
3752 | { | |
3753 | thisblock->data.block.last_unconditional_cleanup | |
3754 | = get_last_insn (); | |
3755 | thisblock->data.block.cleanup_ptr = &thisblock->data.block.cleanups; | |
3756 | } | |
28d81abb RK |
3757 | } |
3758 | return 1; | |
3759 | } | |
e976b8b2 | 3760 | |
c7ae64f2 JM |
3761 | /* Like expand_decl_cleanup, but suppress generating an exception handler |
3762 | to perform the cleanup. */ | |
3763 | ||
3764 | int | |
3765 | expand_decl_cleanup_no_eh (decl, cleanup) | |
3766 | tree decl, cleanup; | |
3767 | { | |
3768 | int save_eh = using_eh_for_cleanups_p; | |
b472527b JL |
3769 | int result; |
3770 | ||
c7ae64f2 | 3771 | using_eh_for_cleanups_p = 0; |
b472527b | 3772 | result = expand_decl_cleanup (decl, cleanup); |
c7ae64f2 | 3773 | using_eh_for_cleanups_p = save_eh; |
b472527b JL |
3774 | |
3775 | return result; | |
c7ae64f2 JM |
3776 | } |
3777 | ||
e976b8b2 | 3778 | /* Arrange for the top element of the dynamic cleanup chain to be |
4c581243 MS |
3779 | popped if we exit the current binding contour. DECL is the |
3780 | associated declaration, if any, otherwise NULL_TREE. If the | |
3781 | current contour is left via an exception, then __sjthrow will pop | |
3782 | the top element off the dynamic cleanup chain. The code that | |
3783 | avoids doing the action we push into the cleanup chain in the | |
3784 | exceptional case is contained in expand_cleanups. | |
e976b8b2 MS |
3785 | |
3786 | This routine is only used by expand_eh_region_start, and that is | |
3787 | the only way in which an exception region should be started. This | |
3788 | routine is only used when using the setjmp/longjmp codegen method | |
3789 | for exception handling. */ | |
3790 | ||
3791 | int | |
4c581243 MS |
3792 | expand_dcc_cleanup (decl) |
3793 | tree decl; | |
e976b8b2 MS |
3794 | { |
3795 | struct nesting *thisblock = block_stack; | |
3796 | tree cleanup; | |
3797 | ||
3798 | /* Error if we are not in any block. */ | |
3799 | if (thisblock == 0) | |
3800 | return 0; | |
3801 | ||
3802 | /* Record the cleanup for the dynamic handler chain. */ | |
3803 | ||
3804 | /* All cleanups must be on the function_obstack. */ | |
3805 | push_obstacks_nochange (); | |
3806 | resume_temporary_allocation (); | |
3807 | cleanup = make_node (POPDCC_EXPR); | |
3808 | pop_obstacks (); | |
3809 | ||
3810 | /* Add the cleanup in a manner similar to expand_decl_cleanup. */ | |
3811 | thisblock->data.block.cleanups | |
4c581243 | 3812 | = temp_tree_cons (decl, cleanup, thisblock->data.block.cleanups); |
e976b8b2 MS |
3813 | |
3814 | /* If this block has a cleanup, it belongs in stack_block_stack. */ | |
3815 | stack_block_stack = thisblock; | |
3816 | return 1; | |
3817 | } | |
3818 | ||
3819 | /* Arrange for the top element of the dynamic handler chain to be | |
4c581243 | 3820 | popped if we exit the current binding contour. DECL is the |
956d6950 | 3821 | associated declaration, if any, otherwise NULL_TREE. If the current |
4c581243 MS |
3822 | contour is left via an exception, then __sjthrow will pop the top |
3823 | element off the dynamic handler chain. The code that avoids doing | |
3824 | the action we push into the handler chain in the exceptional case | |
3825 | is contained in expand_cleanups. | |
e976b8b2 MS |
3826 | |
3827 | This routine is only used by expand_eh_region_start, and that is | |
3828 | the only way in which an exception region should be started. This | |
3829 | routine is only used when using the setjmp/longjmp codegen method | |
3830 | for exception handling. */ | |
3831 | ||
3832 | int | |
4c581243 MS |
3833 | expand_dhc_cleanup (decl) |
3834 | tree decl; | |
e976b8b2 MS |
3835 | { |
3836 | struct nesting *thisblock = block_stack; | |
3837 | tree cleanup; | |
3838 | ||
3839 | /* Error if we are not in any block. */ | |
3840 | if (thisblock == 0) | |
3841 | return 0; | |
3842 | ||
3843 | /* Record the cleanup for the dynamic handler chain. */ | |
3844 | ||
3845 | /* All cleanups must be on the function_obstack. */ | |
3846 | push_obstacks_nochange (); | |
3847 | resume_temporary_allocation (); | |
3848 | cleanup = make_node (POPDHC_EXPR); | |
3849 | pop_obstacks (); | |
3850 | ||
3851 | /* Add the cleanup in a manner similar to expand_decl_cleanup. */ | |
3852 | thisblock->data.block.cleanups | |
4c581243 | 3853 | = temp_tree_cons (decl, cleanup, thisblock->data.block.cleanups); |
e976b8b2 MS |
3854 | |
3855 | /* If this block has a cleanup, it belongs in stack_block_stack. */ | |
3856 | stack_block_stack = thisblock; | |
3857 | return 1; | |
3858 | } | |
28d81abb RK |
3859 | \f |
3860 | /* DECL is an anonymous union. CLEANUP is a cleanup for DECL. | |
3861 | DECL_ELTS is the list of elements that belong to DECL's type. | |
3862 | In each, the TREE_VALUE is a VAR_DECL, and the TREE_PURPOSE a cleanup. */ | |
3863 | ||
3864 | void | |
3865 | expand_anon_union_decl (decl, cleanup, decl_elts) | |
3866 | tree decl, cleanup, decl_elts; | |
3867 | { | |
3868 | struct nesting *thisblock = block_stack; | |
3869 | rtx x; | |
3870 | ||
ec5cd386 RK |
3871 | expand_decl (decl); |
3872 | expand_decl_cleanup (decl, cleanup); | |
28d81abb RK |
3873 | x = DECL_RTL (decl); |
3874 | ||
3875 | while (decl_elts) | |
3876 | { | |
3877 | tree decl_elt = TREE_VALUE (decl_elts); | |
3878 | tree cleanup_elt = TREE_PURPOSE (decl_elts); | |
3879 | enum machine_mode mode = TYPE_MODE (TREE_TYPE (decl_elt)); | |
3880 | ||
7b9032dd JM |
3881 | /* Propagate the union's alignment to the elements. */ |
3882 | DECL_ALIGN (decl_elt) = DECL_ALIGN (decl); | |
3883 | ||
3884 | /* If the element has BLKmode and the union doesn't, the union is | |
3885 | aligned such that the element doesn't need to have BLKmode, so | |
3886 | change the element's mode to the appropriate one for its size. */ | |
3887 | if (mode == BLKmode && DECL_MODE (decl) != BLKmode) | |
3888 | DECL_MODE (decl_elt) = mode | |
3889 | = mode_for_size (TREE_INT_CST_LOW (DECL_SIZE (decl_elt)), | |
3890 | MODE_INT, 1); | |
3891 | ||
28d81abb RK |
3892 | /* (SUBREG (MEM ...)) at RTL generation time is invalid, so we |
3893 | instead create a new MEM rtx with the proper mode. */ | |
3894 | if (GET_CODE (x) == MEM) | |
3895 | { | |
3896 | if (mode == GET_MODE (x)) | |
3897 | DECL_RTL (decl_elt) = x; | |
3898 | else | |
3899 | { | |
38a448ca | 3900 | DECL_RTL (decl_elt) = gen_rtx_MEM (mode, copy_rtx (XEXP (x, 0))); |
c6df88cb | 3901 | MEM_COPY_ATTRIBUTES (DECL_RTL (decl_elt), x); |
28d81abb RK |
3902 | RTX_UNCHANGING_P (DECL_RTL (decl_elt)) = RTX_UNCHANGING_P (x); |
3903 | } | |
3904 | } | |
3905 | else if (GET_CODE (x) == REG) | |
3906 | { | |
3907 | if (mode == GET_MODE (x)) | |
3908 | DECL_RTL (decl_elt) = x; | |
3909 | else | |
38a448ca | 3910 | DECL_RTL (decl_elt) = gen_rtx_SUBREG (mode, x, 0); |
28d81abb RK |
3911 | } |
3912 | else | |
3913 | abort (); | |
3914 | ||
3915 | /* Record the cleanup if there is one. */ | |
3916 | ||
3917 | if (cleanup != 0) | |
3918 | thisblock->data.block.cleanups | |
3919 | = temp_tree_cons (decl_elt, cleanup_elt, | |
3920 | thisblock->data.block.cleanups); | |
3921 | ||
3922 | decl_elts = TREE_CHAIN (decl_elts); | |
3923 | } | |
3924 | } | |
3925 | \f | |
3926 | /* Expand a list of cleanups LIST. | |
3927 | Elements may be expressions or may be nested lists. | |
3928 | ||
3929 | If DONT_DO is nonnull, then any list-element | |
3930 | whose TREE_PURPOSE matches DONT_DO is omitted. | |
3931 | This is sometimes used to avoid a cleanup associated with | |
4e44807b MS |
3932 | a value that is being returned out of the scope. |
3933 | ||
3934 | If IN_FIXUP is non-zero, we are generating this cleanup for a fixup | |
50d1b7a1 MS |
3935 | goto and handle protection regions specially in that case. |
3936 | ||
3937 | If REACHABLE, we emit code, otherwise just inform the exception handling | |
3938 | code about this finalization. */ | |
28d81abb RK |
3939 | |
3940 | static void | |
50d1b7a1 | 3941 | expand_cleanups (list, dont_do, in_fixup, reachable) |
28d81abb RK |
3942 | tree list; |
3943 | tree dont_do; | |
4e44807b | 3944 | int in_fixup; |
50d1b7a1 | 3945 | int reachable; |
28d81abb RK |
3946 | { |
3947 | tree tail; | |
3948 | for (tail = list; tail; tail = TREE_CHAIN (tail)) | |
3949 | if (dont_do == 0 || TREE_PURPOSE (tail) != dont_do) | |
3950 | { | |
3951 | if (TREE_CODE (TREE_VALUE (tail)) == TREE_LIST) | |
50d1b7a1 | 3952 | expand_cleanups (TREE_VALUE (tail), dont_do, in_fixup, reachable); |
28d81abb RK |
3953 | else |
3954 | { | |
4e44807b | 3955 | if (! in_fixup) |
e976b8b2 MS |
3956 | { |
3957 | tree cleanup = TREE_VALUE (tail); | |
3958 | ||
3959 | /* See expand_d{h,c}c_cleanup for why we avoid this. */ | |
3960 | if (TREE_CODE (cleanup) != POPDHC_EXPR | |
3961 | && TREE_CODE (cleanup) != POPDCC_EXPR | |
3962 | /* See expand_eh_region_start_tree for this case. */ | |
3963 | && ! TREE_ADDRESSABLE (tail)) | |
3964 | { | |
3965 | cleanup = protect_with_terminate (cleanup); | |
3966 | expand_eh_region_end (cleanup); | |
3967 | } | |
3968 | } | |
61d6b1cc | 3969 | |
50d1b7a1 MS |
3970 | if (reachable) |
3971 | { | |
3972 | /* Cleanups may be run multiple times. For example, | |
3973 | when exiting a binding contour, we expand the | |
3974 | cleanups associated with that contour. When a goto | |
3975 | within that binding contour has a target outside that | |
3976 | contour, it will expand all cleanups from its scope to | |
3977 | the target. Though the cleanups are expanded multiple | |
3978 | times, the control paths are non-overlapping so the | |
3979 | cleanups will not be executed twice. */ | |
9762d48d JM |
3980 | |
3981 | /* We may need to protect fixups with rethrow regions. */ | |
3982 | int protect = (in_fixup && ! TREE_ADDRESSABLE (tail)); | |
e5e809f4 | 3983 | |
9762d48d JM |
3984 | if (protect) |
3985 | expand_fixup_region_start (); | |
e5e809f4 | 3986 | |
50d1b7a1 | 3987 | expand_expr (TREE_VALUE (tail), const0_rtx, VOIDmode, 0); |
9762d48d JM |
3988 | if (protect) |
3989 | expand_fixup_region_end (TREE_VALUE (tail)); | |
50d1b7a1 MS |
3990 | free_temp_slots (); |
3991 | } | |
28d81abb RK |
3992 | } |
3993 | } | |
3994 | } | |
3995 | ||
e976b8b2 MS |
3996 | /* Mark when the context we are emitting RTL for as a conditional |
3997 | context, so that any cleanup actions we register with | |
3998 | expand_decl_init will be properly conditionalized when those | |
3999 | cleanup actions are later performed. Must be called before any | |
956d6950 | 4000 | expression (tree) is expanded that is within a conditional context. */ |
e976b8b2 MS |
4001 | |
4002 | void | |
956d6950 | 4003 | start_cleanup_deferral () |
e976b8b2 | 4004 | { |
e3eef942 JW |
4005 | /* block_stack can be NULL if we are inside the parameter list. It is |
4006 | OK to do nothing, because cleanups aren't possible here. */ | |
4007 | if (block_stack) | |
4008 | ++block_stack->data.block.conditional_code; | |
e976b8b2 MS |
4009 | } |
4010 | ||
4011 | /* Mark the end of a conditional region of code. Because cleanup | |
956d6950 | 4012 | deferrals may be nested, we may still be in a conditional region |
e976b8b2 MS |
4013 | after we end the currently deferred cleanups, only after we end all |
4014 | deferred cleanups, are we back in unconditional code. */ | |
4015 | ||
4016 | void | |
956d6950 | 4017 | end_cleanup_deferral () |
e976b8b2 | 4018 | { |
e3eef942 JW |
4019 | /* block_stack can be NULL if we are inside the parameter list. It is |
4020 | OK to do nothing, because cleanups aren't possible here. */ | |
4021 | if (block_stack) | |
4022 | --block_stack->data.block.conditional_code; | |
e976b8b2 MS |
4023 | } |
4024 | ||
28d81abb RK |
4025 | /* Move all cleanups from the current block_stack |
4026 | to the containing block_stack, where they are assumed to | |
4027 | have been created. If anything can cause a temporary to | |
4028 | be created, but not expanded for more than one level of | |
4029 | block_stacks, then this code will have to change. */ | |
4030 | ||
4031 | void | |
4032 | move_cleanups_up () | |
4033 | { | |
4034 | struct nesting *block = block_stack; | |
4035 | struct nesting *outer = block->next; | |
4036 | ||
4037 | outer->data.block.cleanups | |
4038 | = chainon (block->data.block.cleanups, | |
4039 | outer->data.block.cleanups); | |
4040 | block->data.block.cleanups = 0; | |
4041 | } | |
4042 | ||
4043 | tree | |
4044 | last_cleanup_this_contour () | |
4045 | { | |
4046 | if (block_stack == 0) | |
4047 | return 0; | |
4048 | ||
4049 | return block_stack->data.block.cleanups; | |
4050 | } | |
4051 | ||
4052 | /* Return 1 if there are any pending cleanups at this point. | |
4053 | If THIS_CONTOUR is nonzero, check the current contour as well. | |
4054 | Otherwise, look only at the contours that enclose this one. */ | |
4055 | ||
4056 | int | |
4057 | any_pending_cleanups (this_contour) | |
4058 | int this_contour; | |
4059 | { | |
4060 | struct nesting *block; | |
4061 | ||
4062 | if (block_stack == 0) | |
4063 | return 0; | |
4064 | ||
4065 | if (this_contour && block_stack->data.block.cleanups != NULL) | |
4066 | return 1; | |
4067 | if (block_stack->data.block.cleanups == 0 | |
e976b8b2 | 4068 | && block_stack->data.block.outer_cleanups == 0) |
28d81abb RK |
4069 | return 0; |
4070 | ||
4071 | for (block = block_stack->next; block; block = block->next) | |
4072 | if (block->data.block.cleanups != 0) | |
4073 | return 1; | |
4074 | ||
4075 | return 0; | |
4076 | } | |
4077 | \f | |
4078 | /* Enter a case (Pascal) or switch (C) statement. | |
4079 | Push a block onto case_stack and nesting_stack | |
4080 | to accumulate the case-labels that are seen | |
4081 | and to record the labels generated for the statement. | |
4082 | ||
4083 | EXIT_FLAG is nonzero if `exit_something' should exit this case stmt. | |
4084 | Otherwise, this construct is transparent for `exit_something'. | |
4085 | ||
4086 | EXPR is the index-expression to be dispatched on. | |
4087 | TYPE is its nominal type. We could simply convert EXPR to this type, | |
4088 | but instead we take short cuts. */ | |
4089 | ||
4090 | void | |
4091 | expand_start_case (exit_flag, expr, type, printname) | |
4092 | int exit_flag; | |
4093 | tree expr; | |
4094 | tree type; | |
4095 | char *printname; | |
4096 | { | |
4097 | register struct nesting *thiscase = ALLOC_NESTING (); | |
4098 | ||
4099 | /* Make an entry on case_stack for the case we are entering. */ | |
4100 | ||
4101 | thiscase->next = case_stack; | |
4102 | thiscase->all = nesting_stack; | |
4103 | thiscase->depth = ++nesting_depth; | |
4104 | thiscase->exit_label = exit_flag ? gen_label_rtx () : 0; | |
4105 | thiscase->data.case_stmt.case_list = 0; | |
4106 | thiscase->data.case_stmt.index_expr = expr; | |
4107 | thiscase->data.case_stmt.nominal_type = type; | |
4108 | thiscase->data.case_stmt.default_label = 0; | |
4109 | thiscase->data.case_stmt.num_ranges = 0; | |
4110 | thiscase->data.case_stmt.printname = printname; | |
a11759a3 | 4111 | thiscase->data.case_stmt.line_number_status = force_line_numbers (); |
28d81abb RK |
4112 | case_stack = thiscase; |
4113 | nesting_stack = thiscase; | |
4114 | ||
4115 | do_pending_stack_adjust (); | |
4116 | ||
4117 | /* Make sure case_stmt.start points to something that won't | |
4118 | need any transformation before expand_end_case. */ | |
4119 | if (GET_CODE (get_last_insn ()) != NOTE) | |
37366632 | 4120 | emit_note (NULL_PTR, NOTE_INSN_DELETED); |
28d81abb RK |
4121 | |
4122 | thiscase->data.case_stmt.start = get_last_insn (); | |
4c581243 | 4123 | |
956d6950 | 4124 | start_cleanup_deferral (); |
28d81abb RK |
4125 | } |
4126 | ||
ca695ac9 | 4127 | |
28d81abb RK |
4128 | /* Start a "dummy case statement" within which case labels are invalid |
4129 | and are not connected to any larger real case statement. | |
4130 | This can be used if you don't want to let a case statement jump | |
4131 | into the middle of certain kinds of constructs. */ | |
4132 | ||
4133 | void | |
4134 | expand_start_case_dummy () | |
4135 | { | |
4136 | register struct nesting *thiscase = ALLOC_NESTING (); | |
4137 | ||
4138 | /* Make an entry on case_stack for the dummy. */ | |
4139 | ||
4140 | thiscase->next = case_stack; | |
4141 | thiscase->all = nesting_stack; | |
4142 | thiscase->depth = ++nesting_depth; | |
4143 | thiscase->exit_label = 0; | |
4144 | thiscase->data.case_stmt.case_list = 0; | |
4145 | thiscase->data.case_stmt.start = 0; | |
4146 | thiscase->data.case_stmt.nominal_type = 0; | |
4147 | thiscase->data.case_stmt.default_label = 0; | |
4148 | thiscase->data.case_stmt.num_ranges = 0; | |
4149 | case_stack = thiscase; | |
4150 | nesting_stack = thiscase; | |
956d6950 | 4151 | start_cleanup_deferral (); |
28d81abb RK |
4152 | } |
4153 | ||
4154 | /* End a dummy case statement. */ | |
4155 | ||
4156 | void | |
4157 | expand_end_case_dummy () | |
4158 | { | |
956d6950 | 4159 | end_cleanup_deferral (); |
28d81abb RK |
4160 | POPSTACK (case_stack); |
4161 | } | |
4162 | ||
4163 | /* Return the data type of the index-expression | |
4164 | of the innermost case statement, or null if none. */ | |
4165 | ||
4166 | tree | |
4167 | case_index_expr_type () | |
4168 | { | |
4169 | if (case_stack) | |
4170 | return TREE_TYPE (case_stack->data.case_stmt.index_expr); | |
4171 | return 0; | |
4172 | } | |
4173 | \f | |
a11759a3 JR |
4174 | static void |
4175 | check_seenlabel () | |
4176 | { | |
4177 | /* If this is the first label, warn if any insns have been emitted. */ | |
4178 | if (case_stack->data.case_stmt.line_number_status >= 0) | |
4179 | { | |
4180 | rtx insn; | |
4181 | ||
4182 | restore_line_number_status | |
4183 | (case_stack->data.case_stmt.line_number_status); | |
4184 | case_stack->data.case_stmt.line_number_status = -1; | |
4185 | ||
4186 | for (insn = case_stack->data.case_stmt.start; | |
4187 | insn; | |
4188 | insn = NEXT_INSN (insn)) | |
4189 | { | |
4190 | if (GET_CODE (insn) == CODE_LABEL) | |
4191 | break; | |
4192 | if (GET_CODE (insn) != NOTE | |
4193 | && (GET_CODE (insn) != INSN || GET_CODE (PATTERN (insn)) != USE)) | |
4194 | { | |
4195 | do | |
4196 | insn = PREV_INSN (insn); | |
0dacbd0e JW |
4197 | while (insn && (GET_CODE (insn) != NOTE || NOTE_LINE_NUMBER (insn) < 0)); |
4198 | ||
4199 | /* If insn is zero, then there must have been a syntax error. */ | |
4200 | if (insn) | |
4201 | warning_with_file_and_line (NOTE_SOURCE_FILE(insn), | |
4202 | NOTE_LINE_NUMBER(insn), | |
4203 | "unreachable code at beginning of %s", | |
4204 | case_stack->data.case_stmt.printname); | |
a11759a3 JR |
4205 | break; |
4206 | } | |
4207 | } | |
4208 | } | |
4209 | } | |
4210 | ||
28d81abb RK |
4211 | /* Accumulate one case or default label inside a case or switch statement. |
4212 | VALUE is the value of the case (a null pointer, for a default label). | |
f52fba84 PE |
4213 | The function CONVERTER, when applied to arguments T and V, |
4214 | converts the value V to the type T. | |
28d81abb RK |
4215 | |
4216 | If not currently inside a case or switch statement, return 1 and do | |
4217 | nothing. The caller will print a language-specific error message. | |
4218 | If VALUE is a duplicate or overlaps, return 2 and do nothing | |
4219 | except store the (first) duplicate node in *DUPLICATE. | |
4220 | If VALUE is out of range, return 3 and do nothing. | |
e976b8b2 | 4221 | If we are jumping into the scope of a cleanup or var-sized array, return 5. |
28d81abb RK |
4222 | Return 0 on success. |
4223 | ||
4224 | Extended to handle range statements. */ | |
4225 | ||
4226 | int | |
f52fba84 | 4227 | pushcase (value, converter, label, duplicate) |
28d81abb | 4228 | register tree value; |
f52fba84 | 4229 | tree (*converter) PROTO((tree, tree)); |
28d81abb RK |
4230 | register tree label; |
4231 | tree *duplicate; | |
4232 | { | |
28d81abb RK |
4233 | tree index_type; |
4234 | tree nominal_type; | |
4235 | ||
4236 | /* Fail if not inside a real case statement. */ | |
4237 | if (! (case_stack && case_stack->data.case_stmt.start)) | |
4238 | return 1; | |
4239 | ||
4240 | if (stack_block_stack | |
4241 | && stack_block_stack->depth > case_stack->depth) | |
4242 | return 5; | |
4243 | ||
4244 | index_type = TREE_TYPE (case_stack->data.case_stmt.index_expr); | |
4245 | nominal_type = case_stack->data.case_stmt.nominal_type; | |
4246 | ||
4247 | /* If the index is erroneous, avoid more problems: pretend to succeed. */ | |
4248 | if (index_type == error_mark_node) | |
4249 | return 0; | |
4250 | ||
4251 | /* Convert VALUE to the type in which the comparisons are nominally done. */ | |
4252 | if (value != 0) | |
f52fba84 | 4253 | value = (*converter) (nominal_type, value); |
28d81abb | 4254 | |
feb60352 R |
4255 | check_seenlabel (); |
4256 | ||
28d81abb RK |
4257 | /* Fail if this value is out of range for the actual type of the index |
4258 | (which may be narrower than NOMINAL_TYPE). */ | |
4259 | if (value != 0 && ! int_fits_type_p (value, index_type)) | |
4260 | return 3; | |
4261 | ||
4262 | /* Fail if this is a duplicate or overlaps another entry. */ | |
4263 | if (value == 0) | |
4264 | { | |
4265 | if (case_stack->data.case_stmt.default_label != 0) | |
4266 | { | |
4267 | *duplicate = case_stack->data.case_stmt.default_label; | |
4268 | return 2; | |
4269 | } | |
4270 | case_stack->data.case_stmt.default_label = label; | |
4271 | } | |
4272 | else | |
57641239 | 4273 | return add_case_node (value, value, label, duplicate); |
28d81abb RK |
4274 | |
4275 | expand_label (label); | |
4276 | return 0; | |
4277 | } | |
4278 | ||
956d6950 JL |
4279 | /* Like pushcase but this case applies to all values between VALUE1 and |
4280 | VALUE2 (inclusive). If VALUE1 is NULL, the range starts at the lowest | |
4281 | value of the index type and ends at VALUE2. If VALUE2 is NULL, the range | |
4282 | starts at VALUE1 and ends at the highest value of the index type. | |
4283 | If both are NULL, this case applies to all values. | |
4284 | ||
4285 | The return value is the same as that of pushcase but there is one | |
4286 | additional error code: 4 means the specified range was empty. */ | |
28d81abb RK |
4287 | |
4288 | int | |
f52fba84 | 4289 | pushcase_range (value1, value2, converter, label, duplicate) |
28d81abb | 4290 | register tree value1, value2; |
f52fba84 | 4291 | tree (*converter) PROTO((tree, tree)); |
28d81abb RK |
4292 | register tree label; |
4293 | tree *duplicate; | |
4294 | { | |
28d81abb RK |
4295 | tree index_type; |
4296 | tree nominal_type; | |
4297 | ||
4298 | /* Fail if not inside a real case statement. */ | |
4299 | if (! (case_stack && case_stack->data.case_stmt.start)) | |
4300 | return 1; | |
4301 | ||
4302 | if (stack_block_stack | |
4303 | && stack_block_stack->depth > case_stack->depth) | |
4304 | return 5; | |
4305 | ||
4306 | index_type = TREE_TYPE (case_stack->data.case_stmt.index_expr); | |
4307 | nominal_type = case_stack->data.case_stmt.nominal_type; | |
4308 | ||
4309 | /* If the index is erroneous, avoid more problems: pretend to succeed. */ | |
4310 | if (index_type == error_mark_node) | |
4311 | return 0; | |
4312 | ||
a11759a3 | 4313 | check_seenlabel (); |
28d81abb | 4314 | |
956d6950 JL |
4315 | /* Convert VALUEs to type in which the comparisons are nominally done |
4316 | and replace any unspecified value with the corresponding bound. */ | |
4317 | if (value1 == 0) | |
1974bfb1 | 4318 | value1 = TYPE_MIN_VALUE (index_type); |
956d6950 | 4319 | if (value2 == 0) |
1974bfb1 | 4320 | value2 = TYPE_MAX_VALUE (index_type); |
956d6950 JL |
4321 | |
4322 | /* Fail if the range is empty. Do this before any conversion since | |
4323 | we want to allow out-of-range empty ranges. */ | |
e1ee5cdc | 4324 | if (value2 && tree_int_cst_lt (value2, value1)) |
956d6950 JL |
4325 | return 4; |
4326 | ||
4327 | value1 = (*converter) (nominal_type, value1); | |
e1ee5cdc RH |
4328 | |
4329 | /* If the max was unbounded, use the max of the nominal_type we are | |
4330 | converting to. Do this after the < check above to suppress false | |
4331 | positives. */ | |
4332 | if (!value2) | |
4333 | value2 = TYPE_MAX_VALUE (nominal_type); | |
f52fba84 | 4334 | value2 = (*converter) (nominal_type, value2); |
28d81abb RK |
4335 | |
4336 | /* Fail if these values are out of range. */ | |
956d6950 JL |
4337 | if (TREE_CONSTANT_OVERFLOW (value1) |
4338 | || ! int_fits_type_p (value1, index_type)) | |
28d81abb RK |
4339 | return 3; |
4340 | ||
956d6950 JL |
4341 | if (TREE_CONSTANT_OVERFLOW (value2) |
4342 | || ! int_fits_type_p (value2, index_type)) | |
28d81abb RK |
4343 | return 3; |
4344 | ||
57641239 RK |
4345 | return add_case_node (value1, value2, label, duplicate); |
4346 | } | |
4347 | ||
4348 | /* Do the actual insertion of a case label for pushcase and pushcase_range | |
4349 | into case_stack->data.case_stmt.case_list. Use an AVL tree to avoid | |
4350 | slowdown for large switch statements. */ | |
4351 | ||
4352 | static int | |
4353 | add_case_node (low, high, label, duplicate) | |
4354 | tree low, high; | |
4355 | tree label; | |
4356 | tree *duplicate; | |
4357 | { | |
4358 | struct case_node *p, **q, *r; | |
4359 | ||
4360 | q = &case_stack->data.case_stmt.case_list; | |
4361 | p = *q; | |
4362 | ||
69d4ca36 | 4363 | while ((r = *q)) |
28d81abb | 4364 | { |
57641239 RK |
4365 | p = r; |
4366 | ||
4367 | /* Keep going past elements distinctly greater than HIGH. */ | |
4368 | if (tree_int_cst_lt (high, p->low)) | |
4369 | q = &p->left; | |
4370 | ||
4371 | /* or distinctly less than LOW. */ | |
4372 | else if (tree_int_cst_lt (p->high, low)) | |
4373 | q = &p->right; | |
4374 | ||
4375 | else | |
28d81abb | 4376 | { |
57641239 RK |
4377 | /* We have an overlap; this is an error. */ |
4378 | *duplicate = p->code_label; | |
28d81abb RK |
4379 | return 2; |
4380 | } | |
4381 | } | |
4382 | ||
4383 | /* Add this label to the chain, and succeed. | |
57641239 | 4384 | Copy LOW, HIGH so they are on temporary rather than momentary |
28d81abb RK |
4385 | obstack and will thus survive till the end of the case statement. */ |
4386 | ||
57641239 RK |
4387 | r = (struct case_node *) oballoc (sizeof (struct case_node)); |
4388 | r->low = copy_node (low); | |
28d81abb | 4389 | |
57641239 RK |
4390 | /* If the bounds are equal, turn this into the one-value case. */ |
4391 | ||
4392 | if (tree_int_cst_equal (low, high)) | |
4393 | r->high = r->low; | |
4394 | else | |
4395 | { | |
4396 | r->high = copy_node (high); | |
4397 | case_stack->data.case_stmt.num_ranges++; | |
4398 | } | |
4399 | ||
4400 | r->code_label = label; | |
28d81abb RK |
4401 | expand_label (label); |
4402 | ||
57641239 RK |
4403 | *q = r; |
4404 | r->parent = p; | |
4405 | r->left = 0; | |
4406 | r->right = 0; | |
4407 | r->balance = 0; | |
4408 | ||
4409 | while (p) | |
4410 | { | |
4411 | struct case_node *s; | |
4412 | ||
4413 | if (r == p->left) | |
4414 | { | |
4415 | int b; | |
4416 | ||
4417 | if (! (b = p->balance)) | |
4418 | /* Growth propagation from left side. */ | |
4419 | p->balance = -1; | |
4420 | else if (b < 0) | |
4421 | { | |
4422 | if (r->balance < 0) | |
4423 | { | |
4424 | /* R-Rotation */ | |
51723711 | 4425 | if ((p->left = s = r->right)) |
57641239 RK |
4426 | s->parent = p; |
4427 | ||
4428 | r->right = p; | |
4429 | p->balance = 0; | |
4430 | r->balance = 0; | |
4431 | s = p->parent; | |
4432 | p->parent = r; | |
4433 | ||
51723711 | 4434 | if ((r->parent = s)) |
57641239 RK |
4435 | { |
4436 | if (s->left == p) | |
4437 | s->left = r; | |
4438 | else | |
4439 | s->right = r; | |
4440 | } | |
4441 | else | |
4442 | case_stack->data.case_stmt.case_list = r; | |
4443 | } | |
4444 | else | |
4445 | /* r->balance == +1 */ | |
4446 | { | |
5720c7e7 RK |
4447 | /* LR-Rotation */ |
4448 | ||
57641239 RK |
4449 | int b2; |
4450 | struct case_node *t = r->right; | |
4451 | ||
51723711 | 4452 | if ((p->left = s = t->right)) |
57641239 RK |
4453 | s->parent = p; |
4454 | ||
4455 | t->right = p; | |
51723711 | 4456 | if ((r->right = s = t->left)) |
57641239 RK |
4457 | s->parent = r; |
4458 | ||
4459 | t->left = r; | |
4460 | b = t->balance; | |
4461 | b2 = b < 0; | |
4462 | p->balance = b2; | |
4463 | b2 = -b2 - b; | |
4464 | r->balance = b2; | |
4465 | t->balance = 0; | |
4466 | s = p->parent; | |
4467 | p->parent = t; | |
4468 | r->parent = t; | |
4469 | ||
51723711 | 4470 | if ((t->parent = s)) |
57641239 RK |
4471 | { |
4472 | if (s->left == p) | |
4473 | s->left = t; | |
4474 | else | |
4475 | s->right = t; | |
4476 | } | |
4477 | else | |
4478 | case_stack->data.case_stmt.case_list = t; | |
4479 | } | |
4480 | break; | |
4481 | } | |
4482 | ||
4483 | else | |
4484 | { | |
4485 | /* p->balance == +1; growth of left side balances the node. */ | |
4486 | p->balance = 0; | |
4487 | break; | |
4488 | } | |
4489 | } | |
4490 | else | |
4491 | /* r == p->right */ | |
4492 | { | |
4493 | int b; | |
4494 | ||
4495 | if (! (b = p->balance)) | |
4496 | /* Growth propagation from right side. */ | |
4497 | p->balance++; | |
4498 | else if (b > 0) | |
4499 | { | |
4500 | if (r->balance > 0) | |
4501 | { | |
4502 | /* L-Rotation */ | |
4503 | ||
51723711 | 4504 | if ((p->right = s = r->left)) |
57641239 RK |
4505 | s->parent = p; |
4506 | ||
4507 | r->left = p; | |
4508 | p->balance = 0; | |
4509 | r->balance = 0; | |
4510 | s = p->parent; | |
4511 | p->parent = r; | |
51723711 | 4512 | if ((r->parent = s)) |
57641239 RK |
4513 | { |
4514 | if (s->left == p) | |
4515 | s->left = r; | |
4516 | else | |
4517 | s->right = r; | |
4518 | } | |
4519 | ||
4520 | else | |
4521 | case_stack->data.case_stmt.case_list = r; | |
4522 | } | |
4523 | ||
4524 | else | |
4525 | /* r->balance == -1 */ | |
4526 | { | |
4527 | /* RL-Rotation */ | |
4528 | int b2; | |
4529 | struct case_node *t = r->left; | |
4530 | ||
51723711 | 4531 | if ((p->right = s = t->left)) |
57641239 RK |
4532 | s->parent = p; |
4533 | ||
4534 | t->left = p; | |
4535 | ||
51723711 | 4536 | if ((r->left = s = t->right)) |
57641239 RK |
4537 | s->parent = r; |
4538 | ||
4539 | t->right = r; | |
4540 | b = t->balance; | |
4541 | b2 = b < 0; | |
4542 | r->balance = b2; | |
4543 | b2 = -b2 - b; | |
4544 | p->balance = b2; | |
4545 | t->balance = 0; | |
4546 | s = p->parent; | |
4547 | p->parent = t; | |
4548 | r->parent = t; | |
4549 | ||
51723711 | 4550 | if ((t->parent = s)) |
57641239 RK |
4551 | { |
4552 | if (s->left == p) | |
4553 | s->left = t; | |
4554 | else | |
4555 | s->right = t; | |
4556 | } | |
4557 | ||
4558 | else | |
4559 | case_stack->data.case_stmt.case_list = t; | |
4560 | } | |
4561 | break; | |
4562 | } | |
4563 | else | |
4564 | { | |
4565 | /* p->balance == -1; growth of right side balances the node. */ | |
4566 | p->balance = 0; | |
4567 | break; | |
4568 | } | |
4569 | } | |
4570 | ||
4571 | r = p; | |
4572 | p = p->parent; | |
4573 | } | |
28d81abb RK |
4574 | |
4575 | return 0; | |
4576 | } | |
ca695ac9 | 4577 | |
28d81abb | 4578 | \f |
94d6511c PB |
4579 | /* Returns the number of possible values of TYPE. |
4580 | Returns -1 if the number is unknown or variable. | |
4581 | Returns -2 if the number does not fit in a HOST_WIDE_INT. | |
4582 | Sets *SPARENESS to 2 if TYPE is an ENUMERAL_TYPE whose values | |
4583 | do not increase monotonically (there may be duplicates); | |
4584 | to 1 if the values increase monotonically, but not always by 1; | |
4585 | otherwise sets it to 0. */ | |
4586 | ||
4587 | HOST_WIDE_INT | |
4588 | all_cases_count (type, spareness) | |
4589 | tree type; | |
4590 | int *spareness; | |
4591 | { | |
69d4ca36 | 4592 | HOST_WIDE_INT count; |
94d6511c PB |
4593 | *spareness = 0; |
4594 | ||
4595 | switch (TREE_CODE (type)) | |
4596 | { | |
4597 | tree t; | |
4598 | case BOOLEAN_TYPE: | |
4599 | count = 2; | |
4600 | break; | |
4601 | case CHAR_TYPE: | |
4602 | count = 1 << BITS_PER_UNIT; | |
4603 | break; | |
4604 | default: | |
4605 | case INTEGER_TYPE: | |
4606 | if (TREE_CODE (TYPE_MIN_VALUE (type)) != INTEGER_CST | |
e1ee5cdc | 4607 | || TYPE_MAX_VALUE (type) == NULL |
c02aebe2 | 4608 | || TREE_CODE (TYPE_MAX_VALUE (type)) != INTEGER_CST) |
94d6511c PB |
4609 | return -1; |
4610 | else | |
4611 | { | |
4612 | /* count | |
4613 | = TREE_INT_CST_LOW (TYPE_MAX_VALUE (type)) | |
4614 | - TREE_INT_CST_LOW (TYPE_MIN_VALUE (type)) + 1 | |
0f41302f | 4615 | but with overflow checking. */ |
94d6511c PB |
4616 | tree mint = TYPE_MIN_VALUE (type); |
4617 | tree maxt = TYPE_MAX_VALUE (type); | |
4618 | HOST_WIDE_INT lo, hi; | |
4619 | neg_double(TREE_INT_CST_LOW (mint), TREE_INT_CST_HIGH (mint), | |
4620 | &lo, &hi); | |
4621 | add_double(TREE_INT_CST_LOW (maxt), TREE_INT_CST_HIGH (maxt), | |
4622 | lo, hi, &lo, &hi); | |
4623 | add_double (lo, hi, 1, 0, &lo, &hi); | |
4624 | if (hi != 0 || lo < 0) | |
4625 | return -2; | |
4626 | count = lo; | |
4627 | } | |
4628 | break; | |
4629 | case ENUMERAL_TYPE: | |
4630 | count = 0; | |
4631 | for (t = TYPE_VALUES (type); t != NULL_TREE; t = TREE_CHAIN (t)) | |
4632 | { | |
4633 | if (TREE_CODE (TYPE_MIN_VALUE (type)) != INTEGER_CST | |
4634 | || TREE_CODE (TREE_VALUE (t)) != INTEGER_CST | |
4635 | || TREE_INT_CST_LOW (TYPE_MIN_VALUE (type)) + count | |
4636 | != TREE_INT_CST_LOW (TREE_VALUE (t))) | |
4637 | *spareness = 1; | |
4638 | count++; | |
4639 | } | |
4640 | if (*spareness == 1) | |
4641 | { | |
4642 | tree prev = TREE_VALUE (TYPE_VALUES (type)); | |
4643 | for (t = TYPE_VALUES (type); t = TREE_CHAIN (t), t != NULL_TREE; ) | |
4644 | { | |
4645 | if (! tree_int_cst_lt (prev, TREE_VALUE (t))) | |
4646 | { | |
4647 | *spareness = 2; | |
4648 | break; | |
4649 | } | |
4650 | prev = TREE_VALUE (t); | |
4651 | } | |
4652 | ||
4653 | } | |
4654 | } | |
4655 | return count; | |
4656 | } | |
4657 | ||
4658 | ||
4659 | #define BITARRAY_TEST(ARRAY, INDEX) \ | |
0f41302f MS |
4660 | ((ARRAY)[(unsigned) (INDEX) / HOST_BITS_PER_CHAR]\ |
4661 | & (1 << ((unsigned) (INDEX) % HOST_BITS_PER_CHAR))) | |
94d6511c | 4662 | #define BITARRAY_SET(ARRAY, INDEX) \ |
0f41302f MS |
4663 | ((ARRAY)[(unsigned) (INDEX) / HOST_BITS_PER_CHAR]\ |
4664 | |= 1 << ((unsigned) (INDEX) % HOST_BITS_PER_CHAR)) | |
94d6511c PB |
4665 | |
4666 | /* Set the elements of the bitstring CASES_SEEN (which has length COUNT), | |
4667 | with the case values we have seen, assuming the case expression | |
4668 | has the given TYPE. | |
4669 | SPARSENESS is as determined by all_cases_count. | |
4670 | ||
9faa82d8 | 4671 | The time needed is proportional to COUNT, unless |
94d6511c PB |
4672 | SPARSENESS is 2, in which case quadratic time is needed. */ |
4673 | ||
df03cab5 | 4674 | void |
94d6511c PB |
4675 | mark_seen_cases (type, cases_seen, count, sparseness) |
4676 | tree type; | |
4677 | unsigned char *cases_seen; | |
4678 | long count; | |
4679 | int sparseness; | |
4680 | { | |
94d6511c PB |
4681 | tree next_node_to_try = NULL_TREE; |
4682 | long next_node_offset = 0; | |
4683 | ||
5720c7e7 | 4684 | register struct case_node *n, *root = case_stack->data.case_stmt.case_list; |
94d6511c PB |
4685 | tree val = make_node (INTEGER_CST); |
4686 | TREE_TYPE (val) = type; | |
5720c7e7 RK |
4687 | if (! root) |
4688 | ; /* Do nothing */ | |
4689 | else if (sparseness == 2) | |
94d6511c | 4690 | { |
5720c7e7 RK |
4691 | tree t; |
4692 | HOST_WIDE_INT xlo; | |
4693 | ||
4694 | /* This less efficient loop is only needed to handle | |
4695 | duplicate case values (multiple enum constants | |
4696 | with the same value). */ | |
4697 | TREE_TYPE (val) = TREE_TYPE (root->low); | |
4698 | for (t = TYPE_VALUES (type), xlo = 0; t != NULL_TREE; | |
4699 | t = TREE_CHAIN (t), xlo++) | |
94d6511c | 4700 | { |
5720c7e7 RK |
4701 | TREE_INT_CST_LOW (val) = TREE_INT_CST_LOW (TREE_VALUE (t)); |
4702 | TREE_INT_CST_HIGH (val) = TREE_INT_CST_HIGH (TREE_VALUE (t)); | |
4703 | n = root; | |
4704 | do | |
94d6511c | 4705 | { |
5720c7e7 RK |
4706 | /* Keep going past elements distinctly greater than VAL. */ |
4707 | if (tree_int_cst_lt (val, n->low)) | |
4708 | n = n->left; | |
4709 | ||
4710 | /* or distinctly less than VAL. */ | |
4711 | else if (tree_int_cst_lt (n->high, val)) | |
4712 | n = n->right; | |
4713 | ||
4714 | else | |
94d6511c | 4715 | { |
5720c7e7 RK |
4716 | /* We have found a matching range. */ |
4717 | BITARRAY_SET (cases_seen, xlo); | |
4718 | break; | |
94d6511c PB |
4719 | } |
4720 | } | |
5720c7e7 RK |
4721 | while (n); |
4722 | } | |
4723 | } | |
4724 | else | |
4725 | { | |
4726 | if (root->left) | |
4727 | case_stack->data.case_stmt.case_list = root = case_tree2list (root, 0); | |
4728 | for (n = root; n; n = n->right) | |
4729 | { | |
4730 | TREE_INT_CST_LOW (val) = TREE_INT_CST_LOW (n->low); | |
4731 | TREE_INT_CST_HIGH (val) = TREE_INT_CST_HIGH (n->low); | |
4732 | while ( ! tree_int_cst_lt (n->high, val)) | |
94d6511c | 4733 | { |
5720c7e7 RK |
4734 | /* Calculate (into xlo) the "offset" of the integer (val). |
4735 | The element with lowest value has offset 0, the next smallest | |
4736 | element has offset 1, etc. */ | |
4737 | ||
4738 | HOST_WIDE_INT xlo, xhi; | |
4739 | tree t; | |
94d6511c PB |
4740 | if (sparseness && TYPE_VALUES (type) != NULL_TREE) |
4741 | { | |
4742 | /* The TYPE_VALUES will be in increasing order, so | |
4743 | starting searching where we last ended. */ | |
4744 | t = next_node_to_try; | |
4745 | xlo = next_node_offset; | |
4746 | xhi = 0; | |
4747 | for (;;) | |
4748 | { | |
4749 | if (t == NULL_TREE) | |
4750 | { | |
4751 | t = TYPE_VALUES (type); | |
4752 | xlo = 0; | |
4753 | } | |
4754 | if (tree_int_cst_equal (val, TREE_VALUE (t))) | |
4755 | { | |
4756 | next_node_to_try = TREE_CHAIN (t); | |
4757 | next_node_offset = xlo + 1; | |
4758 | break; | |
4759 | } | |
4760 | xlo++; | |
4761 | t = TREE_CHAIN (t); | |
4762 | if (t == next_node_to_try) | |
5720c7e7 RK |
4763 | { |
4764 | xlo = -1; | |
4765 | break; | |
4766 | } | |
94d6511c PB |
4767 | } |
4768 | } | |
4769 | else | |
4770 | { | |
4771 | t = TYPE_MIN_VALUE (type); | |
4772 | if (t) | |
4773 | neg_double (TREE_INT_CST_LOW (t), TREE_INT_CST_HIGH (t), | |
4774 | &xlo, &xhi); | |
4775 | else | |
4776 | xlo = xhi = 0; | |
4777 | add_double (xlo, xhi, | |
4778 | TREE_INT_CST_LOW (val), TREE_INT_CST_HIGH (val), | |
4779 | &xlo, &xhi); | |
4780 | } | |
4781 | ||
9dd53f1e | 4782 | if (xhi == 0 && xlo >= 0 && xlo < count) |
94d6511c | 4783 | BITARRAY_SET (cases_seen, xlo); |
5720c7e7 RK |
4784 | add_double (TREE_INT_CST_LOW (val), TREE_INT_CST_HIGH (val), |
4785 | 1, 0, | |
4786 | &TREE_INT_CST_LOW (val), &TREE_INT_CST_HIGH (val)); | |
94d6511c | 4787 | } |
94d6511c PB |
4788 | } |
4789 | } | |
4790 | } | |
4791 | ||
28d81abb RK |
4792 | /* Called when the index of a switch statement is an enumerated type |
4793 | and there is no default label. | |
4794 | ||
4795 | Checks that all enumeration literals are covered by the case | |
4796 | expressions of a switch. Also, warn if there are any extra | |
4797 | switch cases that are *not* elements of the enumerated type. | |
4798 | ||
4799 | If all enumeration literals were covered by the case expressions, | |
4800 | turn one of the expressions into the default expression since it should | |
4801 | not be possible to fall through such a switch. */ | |
4802 | ||
4803 | void | |
4804 | check_for_full_enumeration_handling (type) | |
4805 | tree type; | |
4806 | { | |
4807 | register struct case_node *n; | |
28d81abb | 4808 | register tree chain; |
69d4ca36 RL |
4809 | #if 0 /* variable used by 'if 0'ed code below. */ |
4810 | register struct case_node **l; | |
28d81abb | 4811 | int all_values = 1; |
69d4ca36 | 4812 | #endif |
28d81abb | 4813 | |
0f41302f | 4814 | /* True iff the selector type is a numbered set mode. */ |
94d6511c PB |
4815 | int sparseness = 0; |
4816 | ||
0f41302f | 4817 | /* The number of possible selector values. */ |
94d6511c PB |
4818 | HOST_WIDE_INT size; |
4819 | ||
4820 | /* For each possible selector value. a one iff it has been matched | |
0f41302f | 4821 | by a case value alternative. */ |
94d6511c PB |
4822 | unsigned char *cases_seen; |
4823 | ||
0f41302f | 4824 | /* The allocated size of cases_seen, in chars. */ |
94d6511c | 4825 | long bytes_needed; |
94d6511c | 4826 | |
94d6511c PB |
4827 | if (! warn_switch) |
4828 | return; | |
4829 | ||
4830 | size = all_cases_count (type, &sparseness); | |
4831 | bytes_needed = (size + HOST_BITS_PER_CHAR) / HOST_BITS_PER_CHAR; | |
28d81abb | 4832 | |
94d6511c | 4833 | if (size > 0 && size < 600000 |
0f41302f | 4834 | /* We deliberately use malloc here - not xmalloc. */ |
ad03007a | 4835 | && (cases_seen = (unsigned char *) malloc (bytes_needed)) != NULL) |
28d81abb | 4836 | { |
94d6511c PB |
4837 | long i; |
4838 | tree v = TYPE_VALUES (type); | |
4839 | bzero (cases_seen, bytes_needed); | |
28d81abb | 4840 | |
94d6511c PB |
4841 | /* The time complexity of this code is normally O(N), where |
4842 | N being the number of members in the enumerated type. | |
4843 | However, if type is a ENUMERAL_TYPE whose values do not | |
0f41302f | 4844 | increase monotonically, O(N*log(N)) time may be needed. */ |
94d6511c PB |
4845 | |
4846 | mark_seen_cases (type, cases_seen, size, sparseness); | |
4847 | ||
4848 | for (i = 0; v != NULL_TREE && i < size; i++, v = TREE_CHAIN (v)) | |
28d81abb | 4849 | { |
94d6511c | 4850 | if (BITARRAY_TEST(cases_seen, i) == 0) |
1ddde1cd | 4851 | warning ("enumeration value `%s' not handled in switch", |
94d6511c | 4852 | IDENTIFIER_POINTER (TREE_PURPOSE (v))); |
28d81abb | 4853 | } |
94d6511c PB |
4854 | |
4855 | free (cases_seen); | |
28d81abb RK |
4856 | } |
4857 | ||
4858 | /* Now we go the other way around; we warn if there are case | |
ac2a9454 | 4859 | expressions that don't correspond to enumerators. This can |
28d81abb | 4860 | occur since C and C++ don't enforce type-checking of |
0f41302f | 4861 | assignments to enumeration variables. */ |
28d81abb | 4862 | |
5720c7e7 RK |
4863 | if (case_stack->data.case_stmt.case_list |
4864 | && case_stack->data.case_stmt.case_list->left) | |
4865 | case_stack->data.case_stmt.case_list | |
4866 | = case_tree2list (case_stack->data.case_stmt.case_list, 0); | |
28d81abb RK |
4867 | if (warn_switch) |
4868 | for (n = case_stack->data.case_stmt.case_list; n; n = n->right) | |
4869 | { | |
4870 | for (chain = TYPE_VALUES (type); | |
4871 | chain && !tree_int_cst_equal (n->low, TREE_VALUE (chain)); | |
4872 | chain = TREE_CHAIN (chain)) | |
4873 | ; | |
4874 | ||
4875 | if (!chain) | |
3b24f55b RS |
4876 | { |
4877 | if (TYPE_NAME (type) == 0) | |
e016950d KG |
4878 | warning ("case value `%ld' not in enumerated type", |
4879 | (long) TREE_INT_CST_LOW (n->low)); | |
3b24f55b | 4880 | else |
e016950d KG |
4881 | warning ("case value `%ld' not in enumerated type `%s'", |
4882 | (long) TREE_INT_CST_LOW (n->low), | |
3b24f55b RS |
4883 | IDENTIFIER_POINTER ((TREE_CODE (TYPE_NAME (type)) |
4884 | == IDENTIFIER_NODE) | |
4885 | ? TYPE_NAME (type) | |
4886 | : DECL_NAME (TYPE_NAME (type)))); | |
4887 | } | |
1ddde1cd RS |
4888 | if (!tree_int_cst_equal (n->low, n->high)) |
4889 | { | |
4890 | for (chain = TYPE_VALUES (type); | |
4891 | chain && !tree_int_cst_equal (n->high, TREE_VALUE (chain)); | |
4892 | chain = TREE_CHAIN (chain)) | |
4893 | ; | |
4894 | ||
4895 | if (!chain) | |
3b24f55b RS |
4896 | { |
4897 | if (TYPE_NAME (type) == 0) | |
e016950d KG |
4898 | warning ("case value `%ld' not in enumerated type", |
4899 | (long) TREE_INT_CST_LOW (n->high)); | |
3b24f55b | 4900 | else |
e016950d KG |
4901 | warning ("case value `%ld' not in enumerated type `%s'", |
4902 | (long) TREE_INT_CST_LOW (n->high), | |
3b24f55b RS |
4903 | IDENTIFIER_POINTER ((TREE_CODE (TYPE_NAME (type)) |
4904 | == IDENTIFIER_NODE) | |
4905 | ? TYPE_NAME (type) | |
4906 | : DECL_NAME (TYPE_NAME (type)))); | |
4907 | } | |
1ddde1cd | 4908 | } |
28d81abb RK |
4909 | } |
4910 | ||
ae8cb346 RS |
4911 | #if 0 |
4912 | /* ??? This optimization is disabled because it causes valid programs to | |
4913 | fail. ANSI C does not guarantee that an expression with enum type | |
9faa82d8 | 4914 | will have a value that is the same as one of the enumeration literals. */ |
ae8cb346 | 4915 | |
28d81abb RK |
4916 | /* If all values were found as case labels, make one of them the default |
4917 | label. Thus, this switch will never fall through. We arbitrarily pick | |
4918 | the last one to make the default since this is likely the most | |
4919 | efficient choice. */ | |
4920 | ||
4921 | if (all_values) | |
4922 | { | |
4923 | for (l = &case_stack->data.case_stmt.case_list; | |
4924 | (*l)->right != 0; | |
4925 | l = &(*l)->right) | |
4926 | ; | |
4927 | ||
4928 | case_stack->data.case_stmt.default_label = (*l)->code_label; | |
4929 | *l = 0; | |
4930 | } | |
ae8cb346 | 4931 | #endif /* 0 */ |
28d81abb | 4932 | } |
ca695ac9 | 4933 | |
28d81abb RK |
4934 | \f |
4935 | /* Terminate a case (Pascal) or switch (C) statement | |
9ab0ddd7 | 4936 | in which ORIG_INDEX is the expression to be tested. |
28d81abb RK |
4937 | Generate the code to test it and jump to the right place. */ |
4938 | ||
4939 | void | |
4940 | expand_end_case (orig_index) | |
4941 | tree orig_index; | |
4942 | { | |
3474db0e | 4943 | tree minval, maxval, range, orig_minval; |
28d81abb RK |
4944 | rtx default_label = 0; |
4945 | register struct case_node *n; | |
85066503 | 4946 | unsigned int count; |
28d81abb | 4947 | rtx index; |
ca695ac9 | 4948 | rtx table_label; |
28d81abb RK |
4949 | int ncases; |
4950 | rtx *labelvec; | |
4951 | register int i; | |
4952 | rtx before_case; | |
4953 | register struct nesting *thiscase = case_stack; | |
1b0cb6fc | 4954 | tree index_expr, index_type; |
ca695ac9 JB |
4955 | int unsignedp; |
4956 | ||
ca695ac9 JB |
4957 | table_label = gen_label_rtx (); |
4958 | index_expr = thiscase->data.case_stmt.index_expr; | |
1b0cb6fc RK |
4959 | index_type = TREE_TYPE (index_expr); |
4960 | unsignedp = TREE_UNSIGNED (index_type); | |
28d81abb RK |
4961 | |
4962 | do_pending_stack_adjust (); | |
4963 | ||
feb60352 R |
4964 | /* This might get an spurious warning in the presence of a syntax error; |
4965 | it could be fixed by moving the call to check_seenlabel after the | |
4966 | check for error_mark_node, and copying the code of check_seenlabel that | |
4967 | deals with case_stack->data.case_stmt.line_number_status / | |
4968 | restore_line_number_status in front of the call to end_cleanup_deferral; | |
4969 | However, this might miss some useful warnings in the presence of | |
4970 | non-syntax errors. */ | |
a11759a3 JR |
4971 | check_seenlabel (); |
4972 | ||
28d81abb | 4973 | /* An ERROR_MARK occurs for various reasons including invalid data type. */ |
1b0cb6fc | 4974 | if (index_type != error_mark_node) |
28d81abb RK |
4975 | { |
4976 | /* If switch expression was an enumerated type, check that all | |
4977 | enumeration literals are covered by the cases. | |
4978 | No sense trying this if there's a default case, however. */ | |
4979 | ||
4980 | if (!thiscase->data.case_stmt.default_label | |
4981 | && TREE_CODE (TREE_TYPE (orig_index)) == ENUMERAL_TYPE | |
4982 | && TREE_CODE (index_expr) != INTEGER_CST) | |
4983 | check_for_full_enumeration_handling (TREE_TYPE (orig_index)); | |
4984 | ||
28d81abb RK |
4985 | /* If we don't have a default-label, create one here, |
4986 | after the body of the switch. */ | |
4987 | if (thiscase->data.case_stmt.default_label == 0) | |
4988 | { | |
4989 | thiscase->data.case_stmt.default_label | |
4990 | = build_decl (LABEL_DECL, NULL_TREE, NULL_TREE); | |
4991 | expand_label (thiscase->data.case_stmt.default_label); | |
4992 | } | |
4993 | default_label = label_rtx (thiscase->data.case_stmt.default_label); | |
4994 | ||
4995 | before_case = get_last_insn (); | |
4996 | ||
5720c7e7 RK |
4997 | if (thiscase->data.case_stmt.case_list |
4998 | && thiscase->data.case_stmt.case_list->left) | |
b059139c RK |
4999 | thiscase->data.case_stmt.case_list |
5000 | = case_tree2list(thiscase->data.case_stmt.case_list, 0); | |
5001 | ||
28d81abb RK |
5002 | /* Simplify the case-list before we count it. */ |
5003 | group_case_nodes (thiscase->data.case_stmt.case_list); | |
5004 | ||
5005 | /* Get upper and lower bounds of case values. | |
5006 | Also convert all the case values to the index expr's data type. */ | |
5007 | ||
5008 | count = 0; | |
5009 | for (n = thiscase->data.case_stmt.case_list; n; n = n->right) | |
5010 | { | |
5011 | /* Check low and high label values are integers. */ | |
5012 | if (TREE_CODE (n->low) != INTEGER_CST) | |
5013 | abort (); | |
5014 | if (TREE_CODE (n->high) != INTEGER_CST) | |
5015 | abort (); | |
5016 | ||
1b0cb6fc RK |
5017 | n->low = convert (index_type, n->low); |
5018 | n->high = convert (index_type, n->high); | |
28d81abb RK |
5019 | |
5020 | /* Count the elements and track the largest and smallest | |
5021 | of them (treating them as signed even if they are not). */ | |
5022 | if (count++ == 0) | |
5023 | { | |
5024 | minval = n->low; | |
5025 | maxval = n->high; | |
5026 | } | |
5027 | else | |
5028 | { | |
5029 | if (INT_CST_LT (n->low, minval)) | |
5030 | minval = n->low; | |
5031 | if (INT_CST_LT (maxval, n->high)) | |
5032 | maxval = n->high; | |
5033 | } | |
5034 | /* A range counts double, since it requires two compares. */ | |
5035 | if (! tree_int_cst_equal (n->low, n->high)) | |
5036 | count++; | |
5037 | } | |
5038 | ||
3474db0e RS |
5039 | orig_minval = minval; |
5040 | ||
28d81abb RK |
5041 | /* Compute span of values. */ |
5042 | if (count != 0) | |
1b0cb6fc | 5043 | range = fold (build (MINUS_EXPR, index_type, maxval, minval)); |
28d81abb | 5044 | |
956d6950 | 5045 | end_cleanup_deferral (); |
4c581243 | 5046 | |
1b0cb6fc | 5047 | if (count == 0) |
28d81abb RK |
5048 | { |
5049 | expand_expr (index_expr, const0_rtx, VOIDmode, 0); | |
5050 | emit_queue (); | |
5051 | emit_jump (default_label); | |
5052 | } | |
3474db0e | 5053 | |
28d81abb RK |
5054 | /* If range of values is much bigger than number of values, |
5055 | make a sequence of conditional branches instead of a dispatch. | |
5056 | If the switch-index is a constant, do it this way | |
5057 | because we can optimize it. */ | |
4f73c5dd TW |
5058 | |
5059 | #ifndef CASE_VALUES_THRESHOLD | |
28d81abb | 5060 | #ifdef HAVE_casesi |
4f73c5dd | 5061 | #define CASE_VALUES_THRESHOLD (HAVE_casesi ? 4 : 5) |
28d81abb | 5062 | #else |
4f73c5dd TW |
5063 | /* If machine does not have a case insn that compares the |
5064 | bounds, this means extra overhead for dispatch tables | |
5065 | which raises the threshold for using them. */ | |
5066 | #define CASE_VALUES_THRESHOLD 5 | |
5067 | #endif /* HAVE_casesi */ | |
5068 | #endif /* CASE_VALUES_THRESHOLD */ | |
5069 | ||
5070 | else if (TREE_INT_CST_HIGH (range) != 0 | |
c84e2712 | 5071 | || count < (unsigned int) CASE_VALUES_THRESHOLD |
37366632 RK |
5072 | || ((unsigned HOST_WIDE_INT) (TREE_INT_CST_LOW (range)) |
5073 | > 10 * count) | |
3f6fe18e RK |
5074 | #ifndef ASM_OUTPUT_ADDR_DIFF_ELT |
5075 | || flag_pic | |
5076 | #endif | |
28d81abb | 5077 | || TREE_CODE (index_expr) == INTEGER_CST |
b4ac57ab | 5078 | /* These will reduce to a constant. */ |
28d81abb | 5079 | || (TREE_CODE (index_expr) == CALL_EXPR |
de14fd73 | 5080 | && TREE_CODE (TREE_OPERAND (index_expr, 0)) == ADDR_EXPR |
28d81abb | 5081 | && TREE_CODE (TREE_OPERAND (TREE_OPERAND (index_expr, 0), 0)) == FUNCTION_DECL |
b4ac57ab RS |
5082 | && DECL_FUNCTION_CODE (TREE_OPERAND (TREE_OPERAND (index_expr, 0), 0)) == BUILT_IN_CLASSIFY_TYPE) |
5083 | || (TREE_CODE (index_expr) == COMPOUND_EXPR | |
5084 | && TREE_CODE (TREE_OPERAND (index_expr, 1)) == INTEGER_CST)) | |
28d81abb | 5085 | { |
37366632 | 5086 | index = expand_expr (index_expr, NULL_RTX, VOIDmode, 0); |
28d81abb RK |
5087 | |
5088 | /* If the index is a short or char that we do not have | |
5089 | an insn to handle comparisons directly, convert it to | |
5090 | a full integer now, rather than letting each comparison | |
5091 | generate the conversion. */ | |
5092 | ||
5093 | if (GET_MODE_CLASS (GET_MODE (index)) == MODE_INT | |
5094 | && (cmp_optab->handlers[(int) GET_MODE(index)].insn_code | |
5095 | == CODE_FOR_nothing)) | |
5096 | { | |
5097 | enum machine_mode wider_mode; | |
5098 | for (wider_mode = GET_MODE (index); wider_mode != VOIDmode; | |
5099 | wider_mode = GET_MODE_WIDER_MODE (wider_mode)) | |
5100 | if (cmp_optab->handlers[(int) wider_mode].insn_code | |
5101 | != CODE_FOR_nothing) | |
5102 | { | |
5103 | index = convert_to_mode (wider_mode, index, unsignedp); | |
5104 | break; | |
5105 | } | |
5106 | } | |
5107 | ||
5108 | emit_queue (); | |
5109 | do_pending_stack_adjust (); | |
5110 | ||
5111 | index = protect_from_queue (index, 0); | |
5112 | if (GET_CODE (index) == MEM) | |
5113 | index = copy_to_reg (index); | |
5114 | if (GET_CODE (index) == CONST_INT | |
5115 | || TREE_CODE (index_expr) == INTEGER_CST) | |
5116 | { | |
5117 | /* Make a tree node with the proper constant value | |
5118 | if we don't already have one. */ | |
5119 | if (TREE_CODE (index_expr) != INTEGER_CST) | |
5120 | { | |
5121 | index_expr | |
5122 | = build_int_2 (INTVAL (index), | |
e9a042b6 | 5123 | unsignedp || INTVAL (index) >= 0 ? 0 : -1); |
1b0cb6fc | 5124 | index_expr = convert (index_type, index_expr); |
28d81abb RK |
5125 | } |
5126 | ||
5127 | /* For constant index expressions we need only | |
5128 | issue a unconditional branch to the appropriate | |
5129 | target code. The job of removing any unreachable | |
5130 | code is left to the optimisation phase if the | |
5131 | "-O" option is specified. */ | |
1b0cb6fc RK |
5132 | for (n = thiscase->data.case_stmt.case_list; n; n = n->right) |
5133 | if (! tree_int_cst_lt (index_expr, n->low) | |
5134 | && ! tree_int_cst_lt (n->high, index_expr)) | |
5135 | break; | |
5136 | ||
28d81abb RK |
5137 | if (n) |
5138 | emit_jump (label_rtx (n->code_label)); | |
5139 | else | |
5140 | emit_jump (default_label); | |
5141 | } | |
5142 | else | |
5143 | { | |
5144 | /* If the index expression is not constant we generate | |
5145 | a binary decision tree to select the appropriate | |
5146 | target code. This is done as follows: | |
5147 | ||
5148 | The list of cases is rearranged into a binary tree, | |
5149 | nearly optimal assuming equal probability for each case. | |
5150 | ||
5151 | The tree is transformed into RTL, eliminating | |
5152 | redundant test conditions at the same time. | |
5153 | ||
5154 | If program flow could reach the end of the | |
5155 | decision tree an unconditional jump to the | |
5156 | default code is emitted. */ | |
5157 | ||
5158 | use_cost_table | |
5159 | = (TREE_CODE (TREE_TYPE (orig_index)) != ENUMERAL_TYPE | |
28d81abb | 5160 | && estimate_case_costs (thiscase->data.case_stmt.case_list)); |
37366632 RK |
5161 | balance_case_nodes (&thiscase->data.case_stmt.case_list, |
5162 | NULL_PTR); | |
28d81abb | 5163 | emit_case_nodes (index, thiscase->data.case_stmt.case_list, |
1b0cb6fc | 5164 | default_label, index_type); |
28d81abb RK |
5165 | emit_jump_if_reachable (default_label); |
5166 | } | |
5167 | } | |
5168 | else | |
5169 | { | |
5170 | int win = 0; | |
5171 | #ifdef HAVE_casesi | |
5172 | if (HAVE_casesi) | |
5173 | { | |
c4fcf531 | 5174 | enum machine_mode index_mode = SImode; |
5130a5cc | 5175 | int index_bits = GET_MODE_BITSIZE (index_mode); |
086f237d JW |
5176 | rtx op1, op2; |
5177 | enum machine_mode op_mode; | |
c4fcf531 | 5178 | |
28d81abb | 5179 | /* Convert the index to SImode. */ |
1b0cb6fc | 5180 | if (GET_MODE_BITSIZE (TYPE_MODE (index_type)) |
c4fcf531 | 5181 | > GET_MODE_BITSIZE (index_mode)) |
28d81abb | 5182 | { |
1b0cb6fc | 5183 | enum machine_mode omode = TYPE_MODE (index_type); |
37366632 | 5184 | rtx rangertx = expand_expr (range, NULL_RTX, VOIDmode, 0); |
af2682ef RS |
5185 | |
5186 | /* We must handle the endpoints in the original mode. */ | |
1b0cb6fc | 5187 | index_expr = build (MINUS_EXPR, index_type, |
28d81abb RK |
5188 | index_expr, minval); |
5189 | minval = integer_zero_node; | |
37366632 | 5190 | index = expand_expr (index_expr, NULL_RTX, VOIDmode, 0); |
c5d5d461 JL |
5191 | emit_cmp_and_jump_insns (rangertx, index, LTU, NULL_RTX, |
5192 | omode, 1, 0, default_label); | |
af2682ef RS |
5193 | /* Now we can safely truncate. */ |
5194 | index = convert_to_mode (index_mode, index, 0); | |
5195 | } | |
5196 | else | |
5197 | { | |
1b0cb6fc | 5198 | if (TYPE_MODE (index_type) != index_mode) |
d3b35d75 RK |
5199 | { |
5200 | index_expr = convert (type_for_size (index_bits, 0), | |
5201 | index_expr); | |
5202 | index_type = TREE_TYPE (index_expr); | |
5203 | } | |
5204 | ||
37366632 | 5205 | index = expand_expr (index_expr, NULL_RTX, VOIDmode, 0); |
28d81abb | 5206 | } |
28d81abb RK |
5207 | emit_queue (); |
5208 | index = protect_from_queue (index, 0); | |
5209 | do_pending_stack_adjust (); | |
5210 | ||
086f237d JW |
5211 | op_mode = insn_operand_mode[(int)CODE_FOR_casesi][0]; |
5212 | if (! (*insn_operand_predicate[(int)CODE_FOR_casesi][0]) | |
5213 | (index, op_mode)) | |
5214 | index = copy_to_mode_reg (op_mode, index); | |
5215 | ||
5216 | op1 = expand_expr (minval, NULL_RTX, VOIDmode, 0); | |
5217 | ||
5218 | op_mode = insn_operand_mode[(int)CODE_FOR_casesi][1]; | |
5219 | if (! (*insn_operand_predicate[(int)CODE_FOR_casesi][1]) | |
5220 | (op1, op_mode)) | |
5221 | op1 = copy_to_mode_reg (op_mode, op1); | |
5222 | ||
5223 | op2 = expand_expr (range, NULL_RTX, VOIDmode, 0); | |
5224 | ||
5225 | op_mode = insn_operand_mode[(int)CODE_FOR_casesi][2]; | |
5226 | if (! (*insn_operand_predicate[(int)CODE_FOR_casesi][2]) | |
5227 | (op2, op_mode)) | |
5228 | op2 = copy_to_mode_reg (op_mode, op2); | |
5229 | ||
5230 | emit_jump_insn (gen_casesi (index, op1, op2, | |
28d81abb RK |
5231 | table_label, default_label)); |
5232 | win = 1; | |
5233 | } | |
5234 | #endif | |
5235 | #ifdef HAVE_tablejump | |
5236 | if (! win && HAVE_tablejump) | |
5237 | { | |
5238 | index_expr = convert (thiscase->data.case_stmt.nominal_type, | |
1b0cb6fc | 5239 | fold (build (MINUS_EXPR, index_type, |
b4ac57ab | 5240 | index_expr, minval))); |
d3b35d75 | 5241 | index_type = TREE_TYPE (index_expr); |
37366632 | 5242 | index = expand_expr (index_expr, NULL_RTX, VOIDmode, 0); |
28d81abb | 5243 | emit_queue (); |
af2682ef | 5244 | index = protect_from_queue (index, 0); |
28d81abb RK |
5245 | do_pending_stack_adjust (); |
5246 | ||
1b0cb6fc | 5247 | do_tablejump (index, TYPE_MODE (index_type), |
37366632 | 5248 | expand_expr (range, NULL_RTX, VOIDmode, 0), |
28d81abb RK |
5249 | table_label, default_label); |
5250 | win = 1; | |
5251 | } | |
5252 | #endif | |
5253 | if (! win) | |
5254 | abort (); | |
5255 | ||
5256 | /* Get table of labels to jump to, in order of case index. */ | |
5257 | ||
5258 | ncases = TREE_INT_CST_LOW (range) + 1; | |
5259 | labelvec = (rtx *) alloca (ncases * sizeof (rtx)); | |
4c9a05bc | 5260 | bzero ((char *) labelvec, ncases * sizeof (rtx)); |
28d81abb RK |
5261 | |
5262 | for (n = thiscase->data.case_stmt.case_list; n; n = n->right) | |
5263 | { | |
37366632 | 5264 | register HOST_WIDE_INT i |
3474db0e | 5265 | = TREE_INT_CST_LOW (n->low) - TREE_INT_CST_LOW (orig_minval); |
28d81abb RK |
5266 | |
5267 | while (1) | |
5268 | { | |
5269 | labelvec[i] | |
38a448ca | 5270 | = gen_rtx_LABEL_REF (Pmode, label_rtx (n->code_label)); |
3474db0e | 5271 | if (i + TREE_INT_CST_LOW (orig_minval) |
28d81abb RK |
5272 | == TREE_INT_CST_LOW (n->high)) |
5273 | break; | |
5274 | i++; | |
5275 | } | |
5276 | } | |
5277 | ||
5278 | /* Fill in the gaps with the default. */ | |
5279 | for (i = 0; i < ncases; i++) | |
5280 | if (labelvec[i] == 0) | |
38a448ca | 5281 | labelvec[i] = gen_rtx_LABEL_REF (Pmode, default_label); |
28d81abb RK |
5282 | |
5283 | /* Output the table */ | |
5284 | emit_label (table_label); | |
5285 | ||
18543a22 | 5286 | if (CASE_VECTOR_PC_RELATIVE || flag_pic) |
38a448ca RH |
5287 | emit_jump_insn (gen_rtx_ADDR_DIFF_VEC (CASE_VECTOR_MODE, |
5288 | gen_rtx_LABEL_REF (Pmode, table_label), | |
33f7f353 JR |
5289 | gen_rtvec_v (ncases, labelvec), |
5290 | const0_rtx, const0_rtx, 0)); | |
28d81abb | 5291 | else |
38a448ca RH |
5292 | emit_jump_insn (gen_rtx_ADDR_VEC (CASE_VECTOR_MODE, |
5293 | gen_rtvec_v (ncases, labelvec))); | |
28d81abb RK |
5294 | |
5295 | /* If the case insn drops through the table, | |
5296 | after the table we must jump to the default-label. | |
5297 | Otherwise record no drop-through after the table. */ | |
5298 | #ifdef CASE_DROPS_THROUGH | |
5299 | emit_jump (default_label); | |
5300 | #else | |
5301 | emit_barrier (); | |
5302 | #endif | |
5303 | } | |
5304 | ||
915f619f JW |
5305 | before_case = squeeze_notes (NEXT_INSN (before_case), get_last_insn ()); |
5306 | reorder_insns (before_case, get_last_insn (), | |
28d81abb RK |
5307 | thiscase->data.case_stmt.start); |
5308 | } | |
4c581243 | 5309 | else |
956d6950 | 5310 | end_cleanup_deferral (); |
1b0cb6fc | 5311 | |
28d81abb RK |
5312 | if (thiscase->exit_label) |
5313 | emit_label (thiscase->exit_label); | |
5314 | ||
5315 | POPSTACK (case_stack); | |
5316 | ||
5317 | free_temp_slots (); | |
5318 | } | |
5319 | ||
57641239 RK |
5320 | /* Convert the tree NODE into a list linked by the right field, with the left |
5321 | field zeroed. RIGHT is used for recursion; it is a list to be placed | |
5322 | rightmost in the resulting list. */ | |
5323 | ||
5324 | static struct case_node * | |
5325 | case_tree2list (node, right) | |
5326 | struct case_node *node, *right; | |
5327 | { | |
5328 | struct case_node *left; | |
5329 | ||
5330 | if (node->right) | |
5331 | right = case_tree2list (node->right, right); | |
5332 | ||
5333 | node->right = right; | |
51723711 | 5334 | if ((left = node->left)) |
57641239 RK |
5335 | { |
5336 | node->left = 0; | |
5337 | return case_tree2list (left, node); | |
5338 | } | |
5339 | ||
5340 | return node; | |
5341 | } | |
ca695ac9 | 5342 | |
28d81abb RK |
5343 | /* Generate code to jump to LABEL if OP1 and OP2 are equal. */ |
5344 | ||
5345 | static void | |
5346 | do_jump_if_equal (op1, op2, label, unsignedp) | |
5347 | rtx op1, op2, label; | |
5348 | int unsignedp; | |
5349 | { | |
5350 | if (GET_CODE (op1) == CONST_INT | |
5351 | && GET_CODE (op2) == CONST_INT) | |
5352 | { | |
5353 | if (INTVAL (op1) == INTVAL (op2)) | |
5354 | emit_jump (label); | |
5355 | } | |
5356 | else | |
5357 | { | |
5358 | enum machine_mode mode = GET_MODE (op1); | |
5359 | if (mode == VOIDmode) | |
5360 | mode = GET_MODE (op2); | |
c5d5d461 JL |
5361 | emit_cmp_and_jump_insns (op1, op2, EQ, NULL_RTX, mode, unsignedp, |
5362 | 0, label); | |
28d81abb RK |
5363 | } |
5364 | } | |
5365 | \f | |
5366 | /* Not all case values are encountered equally. This function | |
5367 | uses a heuristic to weight case labels, in cases where that | |
5368 | looks like a reasonable thing to do. | |
5369 | ||
5370 | Right now, all we try to guess is text, and we establish the | |
5371 | following weights: | |
5372 | ||
5373 | chars above space: 16 | |
5374 | digits: 16 | |
5375 | default: 12 | |
5376 | space, punct: 8 | |
5377 | tab: 4 | |
5378 | newline: 2 | |
5379 | other "\" chars: 1 | |
5380 | remaining chars: 0 | |
5381 | ||
5382 | If we find any cases in the switch that are not either -1 or in the range | |
5383 | of valid ASCII characters, or are control characters other than those | |
5384 | commonly used with "\", don't treat this switch scanning text. | |
5385 | ||
5386 | Return 1 if these nodes are suitable for cost estimation, otherwise | |
5387 | return 0. */ | |
5388 | ||
5389 | static int | |
5390 | estimate_case_costs (node) | |
5391 | case_node_ptr node; | |
5392 | { | |
5393 | tree min_ascii = build_int_2 (-1, -1); | |
5394 | tree max_ascii = convert (TREE_TYPE (node->high), build_int_2 (127, 0)); | |
5395 | case_node_ptr n; | |
5396 | int i; | |
5397 | ||
5398 | /* If we haven't already made the cost table, make it now. Note that the | |
5399 | lower bound of the table is -1, not zero. */ | |
5400 | ||
5401 | if (cost_table == NULL) | |
5402 | { | |
5403 | cost_table = ((short *) xmalloc (129 * sizeof (short))) + 1; | |
4c9a05bc | 5404 | bzero ((char *) (cost_table - 1), 129 * sizeof (short)); |
28d81abb RK |
5405 | |
5406 | for (i = 0; i < 128; i++) | |
5407 | { | |
e9a780ec | 5408 | if (ISALNUM (i)) |
28d81abb | 5409 | cost_table[i] = 16; |
e9a780ec | 5410 | else if (ISPUNCT (i)) |
28d81abb | 5411 | cost_table[i] = 8; |
e9a780ec | 5412 | else if (ISCNTRL (i)) |
28d81abb RK |
5413 | cost_table[i] = -1; |
5414 | } | |
5415 | ||
5416 | cost_table[' '] = 8; | |
5417 | cost_table['\t'] = 4; | |
5418 | cost_table['\0'] = 4; | |
5419 | cost_table['\n'] = 2; | |
5420 | cost_table['\f'] = 1; | |
5421 | cost_table['\v'] = 1; | |
5422 | cost_table['\b'] = 1; | |
5423 | } | |
5424 | ||
5425 | /* See if all the case expressions look like text. It is text if the | |
5426 | constant is >= -1 and the highest constant is <= 127. Do all comparisons | |
5427 | as signed arithmetic since we don't want to ever access cost_table with a | |
5428 | value less than -1. Also check that none of the constants in a range | |
5429 | are strange control characters. */ | |
5430 | ||
5431 | for (n = node; n; n = n->right) | |
5432 | { | |
5433 | if ((INT_CST_LT (n->low, min_ascii)) || INT_CST_LT (max_ascii, n->high)) | |
5434 | return 0; | |
5435 | ||
5436 | for (i = TREE_INT_CST_LOW (n->low); i <= TREE_INT_CST_LOW (n->high); i++) | |
5437 | if (cost_table[i] < 0) | |
5438 | return 0; | |
5439 | } | |
5440 | ||
5441 | /* All interesting values are within the range of interesting | |
5442 | ASCII characters. */ | |
5443 | return 1; | |
5444 | } | |
5445 | ||
5446 | /* Scan an ordered list of case nodes | |
5447 | combining those with consecutive values or ranges. | |
5448 | ||
5449 | Eg. three separate entries 1: 2: 3: become one entry 1..3: */ | |
5450 | ||
5451 | static void | |
5452 | group_case_nodes (head) | |
5453 | case_node_ptr head; | |
5454 | { | |
5455 | case_node_ptr node = head; | |
5456 | ||
5457 | while (node) | |
5458 | { | |
5459 | rtx lb = next_real_insn (label_rtx (node->code_label)); | |
ad7e369f | 5460 | rtx lb2; |
28d81abb RK |
5461 | case_node_ptr np = node; |
5462 | ||
5463 | /* Try to group the successors of NODE with NODE. */ | |
5464 | while (((np = np->right) != 0) | |
5465 | /* Do they jump to the same place? */ | |
ad7e369f JL |
5466 | && ((lb2 = next_real_insn (label_rtx (np->code_label))) == lb |
5467 | || (lb != 0 && lb2 != 0 | |
5468 | && simplejump_p (lb) | |
5469 | && simplejump_p (lb2) | |
5470 | && rtx_equal_p (SET_SRC (PATTERN (lb)), | |
5471 | SET_SRC (PATTERN (lb2))))) | |
28d81abb RK |
5472 | /* Are their ranges consecutive? */ |
5473 | && tree_int_cst_equal (np->low, | |
5474 | fold (build (PLUS_EXPR, | |
5475 | TREE_TYPE (node->high), | |
5476 | node->high, | |
5477 | integer_one_node))) | |
5478 | /* An overflow is not consecutive. */ | |
5479 | && tree_int_cst_lt (node->high, | |
5480 | fold (build (PLUS_EXPR, | |
5481 | TREE_TYPE (node->high), | |
5482 | node->high, | |
5483 | integer_one_node)))) | |
5484 | { | |
5485 | node->high = np->high; | |
5486 | } | |
5487 | /* NP is the first node after NODE which can't be grouped with it. | |
5488 | Delete the nodes in between, and move on to that node. */ | |
5489 | node->right = np; | |
5490 | node = np; | |
5491 | } | |
5492 | } | |
5493 | ||
5494 | /* Take an ordered list of case nodes | |
5495 | and transform them into a near optimal binary tree, | |
6dc42e49 | 5496 | on the assumption that any target code selection value is as |
28d81abb RK |
5497 | likely as any other. |
5498 | ||
5499 | The transformation is performed by splitting the ordered | |
5500 | list into two equal sections plus a pivot. The parts are | |
5501 | then attached to the pivot as left and right branches. Each | |
38e01259 | 5502 | branch is then transformed recursively. */ |
28d81abb RK |
5503 | |
5504 | static void | |
5505 | balance_case_nodes (head, parent) | |
5506 | case_node_ptr *head; | |
5507 | case_node_ptr parent; | |
5508 | { | |
5509 | register case_node_ptr np; | |
5510 | ||
5511 | np = *head; | |
5512 | if (np) | |
5513 | { | |
5514 | int cost = 0; | |
5515 | int i = 0; | |
5516 | int ranges = 0; | |
5517 | register case_node_ptr *npp; | |
5518 | case_node_ptr left; | |
5519 | ||
5520 | /* Count the number of entries on branch. Also count the ranges. */ | |
5521 | ||
5522 | while (np) | |
5523 | { | |
5524 | if (!tree_int_cst_equal (np->low, np->high)) | |
5525 | { | |
5526 | ranges++; | |
5527 | if (use_cost_table) | |
5528 | cost += cost_table[TREE_INT_CST_LOW (np->high)]; | |
5529 | } | |
5530 | ||
5531 | if (use_cost_table) | |
5532 | cost += cost_table[TREE_INT_CST_LOW (np->low)]; | |
5533 | ||
5534 | i++; | |
5535 | np = np->right; | |
5536 | } | |
5537 | ||
5538 | if (i > 2) | |
5539 | { | |
5540 | /* Split this list if it is long enough for that to help. */ | |
5541 | npp = head; | |
5542 | left = *npp; | |
5543 | if (use_cost_table) | |
5544 | { | |
5545 | /* Find the place in the list that bisects the list's total cost, | |
5546 | Here I gets half the total cost. */ | |
5547 | int n_moved = 0; | |
5548 | i = (cost + 1) / 2; | |
5549 | while (1) | |
5550 | { | |
5551 | /* Skip nodes while their cost does not reach that amount. */ | |
5552 | if (!tree_int_cst_equal ((*npp)->low, (*npp)->high)) | |
5553 | i -= cost_table[TREE_INT_CST_LOW ((*npp)->high)]; | |
5554 | i -= cost_table[TREE_INT_CST_LOW ((*npp)->low)]; | |
5555 | if (i <= 0) | |
5556 | break; | |
5557 | npp = &(*npp)->right; | |
5558 | n_moved += 1; | |
5559 | } | |
5560 | if (n_moved == 0) | |
5561 | { | |
5562 | /* Leave this branch lopsided, but optimize left-hand | |
5563 | side and fill in `parent' fields for right-hand side. */ | |
5564 | np = *head; | |
5565 | np->parent = parent; | |
5566 | balance_case_nodes (&np->left, np); | |
5567 | for (; np->right; np = np->right) | |
5568 | np->right->parent = np; | |
5569 | return; | |
5570 | } | |
5571 | } | |
5572 | /* If there are just three nodes, split at the middle one. */ | |
5573 | else if (i == 3) | |
5574 | npp = &(*npp)->right; | |
5575 | else | |
5576 | { | |
5577 | /* Find the place in the list that bisects the list's total cost, | |
5578 | where ranges count as 2. | |
5579 | Here I gets half the total cost. */ | |
5580 | i = (i + ranges + 1) / 2; | |
5581 | while (1) | |
5582 | { | |
5583 | /* Skip nodes while their cost does not reach that amount. */ | |
5584 | if (!tree_int_cst_equal ((*npp)->low, (*npp)->high)) | |
5585 | i--; | |
5586 | i--; | |
5587 | if (i <= 0) | |
5588 | break; | |
5589 | npp = &(*npp)->right; | |
5590 | } | |
5591 | } | |
5592 | *head = np = *npp; | |
5593 | *npp = 0; | |
5594 | np->parent = parent; | |
5595 | np->left = left; | |
5596 | ||
5597 | /* Optimize each of the two split parts. */ | |
5598 | balance_case_nodes (&np->left, np); | |
5599 | balance_case_nodes (&np->right, np); | |
5600 | } | |
5601 | else | |
5602 | { | |
5603 | /* Else leave this branch as one level, | |
5604 | but fill in `parent' fields. */ | |
5605 | np = *head; | |
5606 | np->parent = parent; | |
5607 | for (; np->right; np = np->right) | |
5608 | np->right->parent = np; | |
5609 | } | |
5610 | } | |
5611 | } | |
5612 | \f | |
5613 | /* Search the parent sections of the case node tree | |
5614 | to see if a test for the lower bound of NODE would be redundant. | |
5615 | INDEX_TYPE is the type of the index expression. | |
5616 | ||
5617 | The instructions to generate the case decision tree are | |
5618 | output in the same order as nodes are processed so it is | |
5619 | known that if a parent node checks the range of the current | |
5620 | node minus one that the current node is bounded at its lower | |
5621 | span. Thus the test would be redundant. */ | |
5622 | ||
5623 | static int | |
5624 | node_has_low_bound (node, index_type) | |
5625 | case_node_ptr node; | |
5626 | tree index_type; | |
5627 | { | |
5628 | tree low_minus_one; | |
5629 | case_node_ptr pnode; | |
5630 | ||
5631 | /* If the lower bound of this node is the lowest value in the index type, | |
5632 | we need not test it. */ | |
5633 | ||
5634 | if (tree_int_cst_equal (node->low, TYPE_MIN_VALUE (index_type))) | |
5635 | return 1; | |
5636 | ||
5637 | /* If this node has a left branch, the value at the left must be less | |
5638 | than that at this node, so it cannot be bounded at the bottom and | |
5639 | we need not bother testing any further. */ | |
5640 | ||
5641 | if (node->left) | |
5642 | return 0; | |
5643 | ||
5644 | low_minus_one = fold (build (MINUS_EXPR, TREE_TYPE (node->low), | |
5645 | node->low, integer_one_node)); | |
5646 | ||
5647 | /* If the subtraction above overflowed, we can't verify anything. | |
5648 | Otherwise, look for a parent that tests our value - 1. */ | |
5649 | ||
5650 | if (! tree_int_cst_lt (low_minus_one, node->low)) | |
5651 | return 0; | |
5652 | ||
5653 | for (pnode = node->parent; pnode; pnode = pnode->parent) | |
5654 | if (tree_int_cst_equal (low_minus_one, pnode->high)) | |
5655 | return 1; | |
5656 | ||
5657 | return 0; | |
5658 | } | |
5659 | ||
5660 | /* Search the parent sections of the case node tree | |
5661 | to see if a test for the upper bound of NODE would be redundant. | |
5662 | INDEX_TYPE is the type of the index expression. | |
5663 | ||
5664 | The instructions to generate the case decision tree are | |
5665 | output in the same order as nodes are processed so it is | |
5666 | known that if a parent node checks the range of the current | |
5667 | node plus one that the current node is bounded at its upper | |
5668 | span. Thus the test would be redundant. */ | |
5669 | ||
5670 | static int | |
5671 | node_has_high_bound (node, index_type) | |
5672 | case_node_ptr node; | |
5673 | tree index_type; | |
5674 | { | |
5675 | tree high_plus_one; | |
5676 | case_node_ptr pnode; | |
5677 | ||
e1ee5cdc RH |
5678 | /* If there is no upper bound, obviously no test is needed. */ |
5679 | ||
5680 | if (TYPE_MAX_VALUE (index_type) == NULL) | |
5681 | return 1; | |
5682 | ||
28d81abb RK |
5683 | /* If the upper bound of this node is the highest value in the type |
5684 | of the index expression, we need not test against it. */ | |
5685 | ||
5686 | if (tree_int_cst_equal (node->high, TYPE_MAX_VALUE (index_type))) | |
5687 | return 1; | |
5688 | ||
5689 | /* If this node has a right branch, the value at the right must be greater | |
5690 | than that at this node, so it cannot be bounded at the top and | |
5691 | we need not bother testing any further. */ | |
5692 | ||
5693 | if (node->right) | |
5694 | return 0; | |
5695 | ||
5696 | high_plus_one = fold (build (PLUS_EXPR, TREE_TYPE (node->high), | |
5697 | node->high, integer_one_node)); | |
5698 | ||
5699 | /* If the addition above overflowed, we can't verify anything. | |
5700 | Otherwise, look for a parent that tests our value + 1. */ | |
5701 | ||
5702 | if (! tree_int_cst_lt (node->high, high_plus_one)) | |
5703 | return 0; | |
5704 | ||
5705 | for (pnode = node->parent; pnode; pnode = pnode->parent) | |
5706 | if (tree_int_cst_equal (high_plus_one, pnode->low)) | |
5707 | return 1; | |
5708 | ||
5709 | return 0; | |
5710 | } | |
5711 | ||
5712 | /* Search the parent sections of the | |
5713 | case node tree to see if both tests for the upper and lower | |
5714 | bounds of NODE would be redundant. */ | |
5715 | ||
5716 | static int | |
5717 | node_is_bounded (node, index_type) | |
5718 | case_node_ptr node; | |
5719 | tree index_type; | |
5720 | { | |
5721 | return (node_has_low_bound (node, index_type) | |
5722 | && node_has_high_bound (node, index_type)); | |
5723 | } | |
5724 | ||
5725 | /* Emit an unconditional jump to LABEL unless it would be dead code. */ | |
5726 | ||
5727 | static void | |
5728 | emit_jump_if_reachable (label) | |
5729 | rtx label; | |
5730 | { | |
5731 | if (GET_CODE (get_last_insn ()) != BARRIER) | |
5732 | emit_jump (label); | |
5733 | } | |
5734 | \f | |
5735 | /* Emit step-by-step code to select a case for the value of INDEX. | |
5736 | The thus generated decision tree follows the form of the | |
5737 | case-node binary tree NODE, whose nodes represent test conditions. | |
5738 | INDEX_TYPE is the type of the index of the switch. | |
5739 | ||
5740 | Care is taken to prune redundant tests from the decision tree | |
5741 | by detecting any boundary conditions already checked by | |
5742 | emitted rtx. (See node_has_high_bound, node_has_low_bound | |
5743 | and node_is_bounded, above.) | |
5744 | ||
5745 | Where the test conditions can be shown to be redundant we emit | |
5746 | an unconditional jump to the target code. As a further | |
5747 | optimization, the subordinates of a tree node are examined to | |
5748 | check for bounded nodes. In this case conditional and/or | |
5749 | unconditional jumps as a result of the boundary check for the | |
5750 | current node are arranged to target the subordinates associated | |
38e01259 | 5751 | code for out of bound conditions on the current node. |
28d81abb | 5752 | |
f72aed24 | 5753 | We can assume that when control reaches the code generated here, |
28d81abb RK |
5754 | the index value has already been compared with the parents |
5755 | of this node, and determined to be on the same side of each parent | |
5756 | as this node is. Thus, if this node tests for the value 51, | |
5757 | and a parent tested for 52, we don't need to consider | |
5758 | the possibility of a value greater than 51. If another parent | |
5759 | tests for the value 50, then this node need not test anything. */ | |
5760 | ||
5761 | static void | |
5762 | emit_case_nodes (index, node, default_label, index_type) | |
5763 | rtx index; | |
5764 | case_node_ptr node; | |
5765 | rtx default_label; | |
5766 | tree index_type; | |
5767 | { | |
5768 | /* If INDEX has an unsigned type, we must make unsigned branches. */ | |
5769 | int unsignedp = TREE_UNSIGNED (index_type); | |
ea90cb62 | 5770 | typedef rtx rtx_fn (); |
28d81abb RK |
5771 | enum machine_mode mode = GET_MODE (index); |
5772 | ||
5773 | /* See if our parents have already tested everything for us. | |
5774 | If they have, emit an unconditional jump for this node. */ | |
5775 | if (node_is_bounded (node, index_type)) | |
5776 | emit_jump (label_rtx (node->code_label)); | |
5777 | ||
5778 | else if (tree_int_cst_equal (node->low, node->high)) | |
5779 | { | |
5780 | /* Node is single valued. First see if the index expression matches | |
0f41302f | 5781 | this node and then check our children, if any. */ |
28d81abb | 5782 | |
37366632 | 5783 | do_jump_if_equal (index, expand_expr (node->low, NULL_RTX, VOIDmode, 0), |
28d81abb RK |
5784 | label_rtx (node->code_label), unsignedp); |
5785 | ||
5786 | if (node->right != 0 && node->left != 0) | |
5787 | { | |
5788 | /* This node has children on both sides. | |
5789 | Dispatch to one side or the other | |
5790 | by comparing the index value with this node's value. | |
5791 | If one subtree is bounded, check that one first, | |
5792 | so we can avoid real branches in the tree. */ | |
5793 | ||
5794 | if (node_is_bounded (node->right, index_type)) | |
5795 | { | |
c5d5d461 JL |
5796 | emit_cmp_and_jump_insns (index, expand_expr (node->high, NULL_RTX, |
5797 | VOIDmode, 0), | |
5798 | GT, NULL_RTX, mode, unsignedp, 0, | |
5799 | label_rtx (node->right->code_label)); | |
28d81abb RK |
5800 | emit_case_nodes (index, node->left, default_label, index_type); |
5801 | } | |
5802 | ||
5803 | else if (node_is_bounded (node->left, index_type)) | |
5804 | { | |
c5d5d461 JL |
5805 | emit_cmp_and_jump_insns (index, expand_expr (node->high, NULL_RTX, |
5806 | VOIDmode, 0), | |
5807 | LT, NULL_RTX, mode, unsignedp, 0, | |
5808 | label_rtx (node->left->code_label)); | |
28d81abb RK |
5809 | emit_case_nodes (index, node->right, default_label, index_type); |
5810 | } | |
5811 | ||
5812 | else | |
5813 | { | |
5814 | /* Neither node is bounded. First distinguish the two sides; | |
5815 | then emit the code for one side at a time. */ | |
5816 | ||
5817 | tree test_label | |
5818 | = build_decl (LABEL_DECL, NULL_TREE, NULL_TREE); | |
5819 | ||
5820 | /* See if the value is on the right. */ | |
c5d5d461 JL |
5821 | emit_cmp_and_jump_insns (index, expand_expr (node->high, NULL_RTX, |
5822 | VOIDmode, 0), | |
5823 | GT, NULL_RTX, mode, unsignedp, 0, | |
5824 | label_rtx (test_label)); | |
28d81abb RK |
5825 | |
5826 | /* Value must be on the left. | |
5827 | Handle the left-hand subtree. */ | |
5828 | emit_case_nodes (index, node->left, default_label, index_type); | |
5829 | /* If left-hand subtree does nothing, | |
5830 | go to default. */ | |
5831 | emit_jump_if_reachable (default_label); | |
5832 | ||
5833 | /* Code branches here for the right-hand subtree. */ | |
5834 | expand_label (test_label); | |
5835 | emit_case_nodes (index, node->right, default_label, index_type); | |
5836 | } | |
5837 | } | |
5838 | ||
5839 | else if (node->right != 0 && node->left == 0) | |
5840 | { | |
5841 | /* Here we have a right child but no left so we issue conditional | |
5842 | branch to default and process the right child. | |
5843 | ||
5844 | Omit the conditional branch to default if we it avoid only one | |
5845 | right child; it costs too much space to save so little time. */ | |
5846 | ||
de14fd73 | 5847 | if (node->right->right || node->right->left |
28d81abb RK |
5848 | || !tree_int_cst_equal (node->right->low, node->right->high)) |
5849 | { | |
5850 | if (!node_has_low_bound (node, index_type)) | |
5851 | { | |
c5d5d461 JL |
5852 | emit_cmp_and_jump_insns (index, expand_expr (node->high, |
5853 | NULL_RTX, | |
5854 | VOIDmode, 0), | |
5855 | LT, NULL_RTX, mode, unsignedp, 0, | |
5856 | default_label); | |
28d81abb RK |
5857 | } |
5858 | ||
5859 | emit_case_nodes (index, node->right, default_label, index_type); | |
5860 | } | |
5861 | else | |
5862 | /* We cannot process node->right normally | |
5863 | since we haven't ruled out the numbers less than | |
5864 | this node's value. So handle node->right explicitly. */ | |
5865 | do_jump_if_equal (index, | |
37366632 RK |
5866 | expand_expr (node->right->low, NULL_RTX, |
5867 | VOIDmode, 0), | |
28d81abb RK |
5868 | label_rtx (node->right->code_label), unsignedp); |
5869 | } | |
5870 | ||
5871 | else if (node->right == 0 && node->left != 0) | |
5872 | { | |
5873 | /* Just one subtree, on the left. */ | |
5874 | ||
de14fd73 RK |
5875 | #if 0 /* The following code and comment were formerly part |
5876 | of the condition here, but they didn't work | |
5877 | and I don't understand what the idea was. -- rms. */ | |
5878 | /* If our "most probable entry" is less probable | |
28d81abb RK |
5879 | than the default label, emit a jump to |
5880 | the default label using condition codes | |
5881 | already lying around. With no right branch, | |
5882 | a branch-greater-than will get us to the default | |
5883 | label correctly. */ | |
de14fd73 RK |
5884 | if (use_cost_table |
5885 | && cost_table[TREE_INT_CST_LOW (node->high)] < 12) | |
5886 | ; | |
5887 | #endif /* 0 */ | |
5888 | if (node->left->left || node->left->right | |
28d81abb RK |
5889 | || !tree_int_cst_equal (node->left->low, node->left->high)) |
5890 | { | |
5891 | if (!node_has_high_bound (node, index_type)) | |
5892 | { | |
c5d5d461 JL |
5893 | emit_cmp_and_jump_insns (index, expand_expr (node->high, |
5894 | NULL_RTX, | |
5895 | VOIDmode, 0), | |
5896 | GT, NULL_RTX, mode, unsignedp, 0, | |
5897 | default_label); | |
28d81abb RK |
5898 | } |
5899 | ||
5900 | emit_case_nodes (index, node->left, default_label, index_type); | |
5901 | } | |
5902 | else | |
5903 | /* We cannot process node->left normally | |
5904 | since we haven't ruled out the numbers less than | |
5905 | this node's value. So handle node->left explicitly. */ | |
5906 | do_jump_if_equal (index, | |
37366632 RK |
5907 | expand_expr (node->left->low, NULL_RTX, |
5908 | VOIDmode, 0), | |
28d81abb RK |
5909 | label_rtx (node->left->code_label), unsignedp); |
5910 | } | |
5911 | } | |
5912 | else | |
5913 | { | |
5914 | /* Node is a range. These cases are very similar to those for a single | |
5915 | value, except that we do not start by testing whether this node | |
5916 | is the one to branch to. */ | |
5917 | ||
5918 | if (node->right != 0 && node->left != 0) | |
5919 | { | |
5920 | /* Node has subtrees on both sides. | |
5921 | If the right-hand subtree is bounded, | |
5922 | test for it first, since we can go straight there. | |
5923 | Otherwise, we need to make a branch in the control structure, | |
5924 | then handle the two subtrees. */ | |
5925 | tree test_label = 0; | |
5926 | ||
28d81abb RK |
5927 | |
5928 | if (node_is_bounded (node->right, index_type)) | |
5929 | /* Right hand node is fully bounded so we can eliminate any | |
5930 | testing and branch directly to the target code. */ | |
c5d5d461 JL |
5931 | emit_cmp_and_jump_insns (index, expand_expr (node->high, NULL_RTX, |
5932 | VOIDmode, 0), | |
5933 | GT, NULL_RTX, mode, unsignedp, 0, | |
5934 | label_rtx (node->right->code_label)); | |
28d81abb RK |
5935 | else |
5936 | { | |
5937 | /* Right hand node requires testing. | |
5938 | Branch to a label where we will handle it later. */ | |
5939 | ||
5940 | test_label = build_decl (LABEL_DECL, NULL_TREE, NULL_TREE); | |
c5d5d461 JL |
5941 | emit_cmp_and_jump_insns (index, expand_expr (node->high, NULL_RTX, |
5942 | VOIDmode, 0), | |
5943 | GT, NULL_RTX, mode, unsignedp, 0, | |
5944 | label_rtx (test_label)); | |
28d81abb RK |
5945 | } |
5946 | ||
5947 | /* Value belongs to this node or to the left-hand subtree. */ | |
5948 | ||
c5d5d461 JL |
5949 | emit_cmp_and_jump_insns (index, expand_expr (node->low, NULL_RTX, |
5950 | VOIDmode, 0), | |
5951 | GE, NULL_RTX, mode, unsignedp, 0, | |
5952 | label_rtx (node->code_label)); | |
28d81abb RK |
5953 | |
5954 | /* Handle the left-hand subtree. */ | |
5955 | emit_case_nodes (index, node->left, default_label, index_type); | |
5956 | ||
5957 | /* If right node had to be handled later, do that now. */ | |
5958 | ||
5959 | if (test_label) | |
5960 | { | |
5961 | /* If the left-hand subtree fell through, | |
5962 | don't let it fall into the right-hand subtree. */ | |
5963 | emit_jump_if_reachable (default_label); | |
5964 | ||
5965 | expand_label (test_label); | |
5966 | emit_case_nodes (index, node->right, default_label, index_type); | |
5967 | } | |
5968 | } | |
5969 | ||
5970 | else if (node->right != 0 && node->left == 0) | |
5971 | { | |
5972 | /* Deal with values to the left of this node, | |
5973 | if they are possible. */ | |
5974 | if (!node_has_low_bound (node, index_type)) | |
5975 | { | |
c5d5d461 JL |
5976 | emit_cmp_and_jump_insns (index, expand_expr (node->low, NULL_RTX, |
5977 | VOIDmode, 0), | |
5978 | LT, NULL_RTX, mode, unsignedp, 0, | |
5979 | default_label); | |
28d81abb RK |
5980 | } |
5981 | ||
5982 | /* Value belongs to this node or to the right-hand subtree. */ | |
5983 | ||
c5d5d461 JL |
5984 | emit_cmp_and_jump_insns (index, expand_expr (node->high, NULL_RTX, |
5985 | VOIDmode, 0), | |
5986 | LE, NULL_RTX, mode, unsignedp, 0, | |
5987 | label_rtx (node->code_label)); | |
28d81abb RK |
5988 | |
5989 | emit_case_nodes (index, node->right, default_label, index_type); | |
5990 | } | |
5991 | ||
5992 | else if (node->right == 0 && node->left != 0) | |
5993 | { | |
5994 | /* Deal with values to the right of this node, | |
5995 | if they are possible. */ | |
5996 | if (!node_has_high_bound (node, index_type)) | |
5997 | { | |
c5d5d461 JL |
5998 | emit_cmp_and_jump_insns (index, expand_expr (node->high, NULL_RTX, |
5999 | VOIDmode, 0), | |
6000 | GT, NULL_RTX, mode, unsignedp, 0, | |
6001 | default_label); | |
28d81abb RK |
6002 | } |
6003 | ||
6004 | /* Value belongs to this node or to the left-hand subtree. */ | |
6005 | ||
c5d5d461 JL |
6006 | emit_cmp_and_jump_insns (index, expand_expr (node->low, NULL_RTX, |
6007 | VOIDmode, 0), | |
6008 | GE, NULL_RTX, mode, unsignedp, 0, | |
6009 | label_rtx (node->code_label)); | |
28d81abb RK |
6010 | |
6011 | emit_case_nodes (index, node->left, default_label, index_type); | |
6012 | } | |
6013 | ||
6014 | else | |
6015 | { | |
6016 | /* Node has no children so we check low and high bounds to remove | |
6017 | redundant tests. Only one of the bounds can exist, | |
6018 | since otherwise this node is bounded--a case tested already. */ | |
6019 | ||
6020 | if (!node_has_high_bound (node, index_type)) | |
6021 | { | |
c5d5d461 JL |
6022 | emit_cmp_and_jump_insns (index, expand_expr (node->high, NULL_RTX, |
6023 | VOIDmode, 0), | |
6024 | GT, NULL_RTX, mode, unsignedp, 0, | |
6025 | default_label); | |
28d81abb RK |
6026 | } |
6027 | ||
6028 | if (!node_has_low_bound (node, index_type)) | |
6029 | { | |
c5d5d461 JL |
6030 | emit_cmp_and_jump_insns (index, expand_expr (node->low, NULL_RTX, |
6031 | VOIDmode, 0), | |
6032 | LT, NULL_RTX, mode, unsignedp, 0, | |
6033 | default_label); | |
28d81abb RK |
6034 | } |
6035 | ||
6036 | emit_jump (label_rtx (node->code_label)); | |
6037 | } | |
6038 | } | |
6039 | } | |
6040 | \f | |
6041 | /* These routines are used by the loop unrolling code. They copy BLOCK trees | |
6042 | so that the debugging info will be correct for the unrolled loop. */ | |
6043 | ||
65d98182 JL |
6044 | /* Indexed by block number, contains a pointer to the N'th block node. |
6045 | ||
6046 | Allocated by the call to identify_blocks, then released after the call | |
6047 | to reorder_blocks in the function unroll_block_trees. */ | |
28d81abb | 6048 | |
94dc8b56 | 6049 | static tree *block_vector; |
28d81abb RK |
6050 | |
6051 | void | |
94dc8b56 | 6052 | find_loop_tree_blocks () |
28d81abb | 6053 | { |
94dc8b56 | 6054 | tree block = DECL_INITIAL (current_function_decl); |
28d81abb | 6055 | |
94dc8b56 | 6056 | block_vector = identify_blocks (block, get_insns ()); |
28d81abb RK |
6057 | } |
6058 | ||
28d81abb | 6059 | void |
94dc8b56 | 6060 | unroll_block_trees () |
28d81abb | 6061 | { |
94dc8b56 | 6062 | tree block = DECL_INITIAL (current_function_decl); |
28d81abb | 6063 | |
94dc8b56 | 6064 | reorder_blocks (block_vector, block, get_insns ()); |
65d98182 JL |
6065 | |
6066 | /* Release any memory allocated by identify_blocks. */ | |
6067 | if (block_vector) | |
6068 | free (block_vector); | |
28d81abb | 6069 | } |