1 /* Expands front end tree to back end RTL for GNU C-Compiler
2 Copyright (C) 1987, 1988, 1989, 1992, 1993, 1994, 1995, 1996, 1997,
3 1998, 1999, 2000, 2001 Free Software Foundation, Inc.
5 This file is part of GNU CC.
7 GNU CC is free software; you can redistribute it and/or modify
8 it under the terms of the GNU General Public License as published by
9 the Free Software Foundation; either version 2, or (at your option)
12 GNU CC is distributed in the hope that it will be useful,
13 but WITHOUT ANY WARRANTY; without even the implied warranty of
14 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 GNU General Public License for more details.
17 You should have received a copy of the GNU General Public License
18 along with GNU CC; see the file COPYING. If not, write to
19 the Free Software Foundation, 59 Temple Place - Suite 330,
20 Boston, MA 02111-1307, USA. */
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.
27 The functions whose names start with `expand_' are called by the
28 parser to generate RTL instructions for various kinds of constructs.
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. */
45 #include "insn-config.h"
47 #include "hard-reg-set.h"
56 #define obstack_chunk_alloc xmalloc
57 #define obstack_chunk_free free
58 struct obstack stmt_obstack
;
60 /* Assume that case vectors are not pc-relative. */
61 #ifndef CASE_VECTOR_PC_RELATIVE
62 #define CASE_VECTOR_PC_RELATIVE 0
65 /* Functions and data structures for expanding case statements. */
67 /* Case label structure, used to hold info on labels within case
68 statements. We handle "range" labels; for a single-value label
69 as in C, the high and low limits are the same.
71 An AVL tree of case nodes is initially created, and later transformed
72 to a list linked via the RIGHT fields in the nodes. Nodes with
73 higher case values are later in the list.
75 Switch statements can be output in one of two forms. A branch table
76 is used if there are more than a few labels and the labels are dense
77 within the range between the smallest and largest case value. If a
78 branch table is used, no further manipulations are done with the case
81 The alternative to the use of a branch table is to generate a series
82 of compare and jump insns. When that is done, we use the LEFT, RIGHT,
83 and PARENT fields to hold a binary tree. Initially the tree is
84 totally unbalanced, with everything on the right. We balance the tree
85 with nodes on the left having lower case values than the parent
86 and nodes on the right having higher values. We then output the tree
91 struct case_node
*left
; /* Left son in binary tree */
92 struct case_node
*right
; /* Right son in binary tree; also node chain */
93 struct case_node
*parent
; /* Parent of node in binary tree */
94 tree low
; /* Lowest index value for this label */
95 tree high
; /* Highest index value for this label */
96 tree code_label
; /* Label to jump to when node matches */
100 typedef struct case_node case_node
;
101 typedef struct case_node
*case_node_ptr
;
103 /* These are used by estimate_case_costs and balance_case_nodes. */
105 /* This must be a signed type, and non-ANSI compilers lack signed char. */
106 static short cost_table_
[129];
107 static int use_cost_table
;
108 static int cost_table_initialized
;
110 /* Special care is needed because we allow -1, but TREE_INT_CST_LOW
112 #define COST_TABLE(I) cost_table_[(unsigned HOST_WIDE_INT)((I) + 1)]
114 /* Stack of control and binding constructs we are currently inside.
116 These constructs begin when you call `expand_start_WHATEVER'
117 and end when you call `expand_end_WHATEVER'. This stack records
118 info about how the construct began that tells the end-function
119 what to do. It also may provide information about the construct
120 to alter the behavior of other constructs within the body.
121 For example, they may affect the behavior of C `break' and `continue'.
123 Each construct gets one `struct nesting' object.
124 All of these objects are chained through the `all' field.
125 `nesting_stack' points to the first object (innermost construct).
126 The position of an entry on `nesting_stack' is in its `depth' field.
128 Each type of construct has its own individual stack.
129 For example, loops have `loop_stack'. Each object points to the
130 next object of the same type through the `next' field.
132 Some constructs are visible to `break' exit-statements and others
133 are not. Which constructs are visible depends on the language.
134 Therefore, the data structure allows each construct to be visible
135 or not, according to the args given when the construct is started.
136 The construct is visible if the `exit_label' field is non-null.
137 In that case, the value should be a CODE_LABEL rtx. */
142 struct nesting
*next
;
147 /* For conds (if-then and if-then-else statements). */
150 /* Label for the end of the if construct.
151 There is none if EXITFLAG was not set
152 and no `else' has been seen yet. */
154 /* Label for the end of this alternative.
155 This may be the end of the if or the next else/elseif. */
161 /* Label at the top of the loop; place to loop back to. */
163 /* Label at the end of the whole construct. */
165 /* Label before a jump that branches to the end of the whole
166 construct. This is where destructors go if any. */
168 /* Label for `continue' statement to jump to;
169 this is in front of the stepper of the loop. */
172 /* For variable binding contours. */
175 /* Sequence number of this binding contour within the function,
176 in order of entry. */
177 int block_start_count
;
178 /* Nonzero => value to restore stack to on exit. */
180 /* The NOTE that starts this contour.
181 Used by expand_goto to check whether the destination
182 is within each contour or not. */
184 /* Innermost containing binding contour that has a stack level. */
185 struct nesting
*innermost_stack_block
;
186 /* List of cleanups to be run on exit from this contour.
187 This is a list of expressions to be evaluated.
188 The TREE_PURPOSE of each link is the ..._DECL node
189 which the cleanup pertains to. */
191 /* List of cleanup-lists of blocks containing this block,
192 as they were at the locus where this block appears.
193 There is an element for each containing block,
194 ordered innermost containing block first.
195 The tail of this list can be 0,
196 if all remaining elements would be empty lists.
197 The element's TREE_VALUE is the cleanup-list of that block,
198 which may be null. */
200 /* Chain of labels defined inside this binding contour.
201 For contours that have stack levels or cleanups. */
202 struct label_chain
*label_chain
;
203 /* Number of function calls seen, as of start of this block. */
204 int n_function_calls
;
205 /* Nonzero if this is associated with a EH region. */
206 int exception_region
;
207 /* The saved target_temp_slot_level from our outer block.
208 We may reset target_temp_slot_level to be the level of
209 this block, if that is done, target_temp_slot_level
210 reverts to the saved target_temp_slot_level at the very
212 int block_target_temp_slot_level
;
213 /* True if we are currently emitting insns in an area of
214 output code that is controlled by a conditional
215 expression. This is used by the cleanup handling code to
216 generate conditional cleanup actions. */
217 int conditional_code
;
218 /* A place to move the start of the exception region for any
219 of the conditional cleanups, must be at the end or after
220 the start of the last unconditional cleanup, and before any
221 conditional branch points. */
222 rtx last_unconditional_cleanup
;
223 /* When in a conditional context, this is the specific
224 cleanup list associated with last_unconditional_cleanup,
225 where we place the conditionalized cleanups. */
228 /* For switch (C) or case (Pascal) statements,
229 and also for dummies (see `expand_start_case_dummy'). */
232 /* The insn after which the case dispatch should finally
233 be emitted. Zero for a dummy. */
235 /* A list of case labels; it is first built as an AVL tree.
236 During expand_end_case, this is converted to a list, and may be
237 rearranged into a nearly balanced binary tree. */
238 struct case_node
*case_list
;
239 /* Label to jump to if no case matches. */
241 /* The expression to be dispatched on. */
243 /* Type that INDEX_EXPR should be converted to. */
245 /* Name of this kind of statement, for warnings. */
246 const char *printname
;
247 /* Used to save no_line_numbers till we see the first case label.
248 We set this to -1 when we see the first case label in this
250 int line_number_status
;
255 /* Allocate and return a new `struct nesting'. */
257 #define ALLOC_NESTING() \
258 (struct nesting *) obstack_alloc (&stmt_obstack, sizeof (struct nesting))
260 /* Pop the nesting stack element by element until we pop off
261 the element which is at the top of STACK.
262 Update all the other stacks, popping off elements from them
263 as we pop them from nesting_stack. */
265 #define POPSTACK(STACK) \
266 do { struct nesting *target = STACK; \
267 struct nesting *this; \
268 do { this = nesting_stack; \
269 if (loop_stack == this) \
270 loop_stack = loop_stack->next; \
271 if (cond_stack == this) \
272 cond_stack = cond_stack->next; \
273 if (block_stack == this) \
274 block_stack = block_stack->next; \
275 if (stack_block_stack == this) \
276 stack_block_stack = stack_block_stack->next; \
277 if (case_stack == this) \
278 case_stack = case_stack->next; \
279 nesting_depth = nesting_stack->depth - 1; \
280 nesting_stack = this->all; \
281 obstack_free (&stmt_obstack, this); } \
282 while (this != target); } while (0)
284 /* In some cases it is impossible to generate code for a forward goto
285 until the label definition is seen. This happens when it may be necessary
286 for the goto to reset the stack pointer: we don't yet know how to do that.
287 So expand_goto puts an entry on this fixup list.
288 Each time a binding contour that resets the stack is exited,
290 If the target label has now been defined, we can insert the proper code. */
294 /* Points to following fixup. */
295 struct goto_fixup
*next
;
296 /* Points to the insn before the jump insn.
297 If more code must be inserted, it goes after this insn. */
299 /* The LABEL_DECL that this jump is jumping to, or 0
300 for break, continue or return. */
302 /* The BLOCK for the place where this goto was found. */
304 /* The CODE_LABEL rtx that this is jumping to. */
306 /* Number of binding contours started in current function
307 before the label reference. */
308 int block_start_count
;
309 /* The outermost stack level that should be restored for this jump.
310 Each time a binding contour that resets the stack is exited,
311 if the target label is *not* yet defined, this slot is updated. */
313 /* List of lists of cleanup expressions to be run by this goto.
314 There is one element for each block that this goto is within.
315 The tail of this list can be 0,
316 if all remaining elements would be empty.
317 The TREE_VALUE contains the cleanup list of that block as of the
318 time this goto was seen.
319 The TREE_ADDRESSABLE flag is 1 for a block that has been exited. */
320 tree cleanup_list_list
;
323 /* Within any binding contour that must restore a stack level,
324 all labels are recorded with a chain of these structures. */
328 /* Points to following fixup. */
329 struct label_chain
*next
;
335 /* Chain of all pending binding contours. */
336 struct nesting
*x_block_stack
;
338 /* If any new stacks are added here, add them to POPSTACKS too. */
340 /* Chain of all pending binding contours that restore stack levels
342 struct nesting
*x_stack_block_stack
;
344 /* Chain of all pending conditional statements. */
345 struct nesting
*x_cond_stack
;
347 /* Chain of all pending loops. */
348 struct nesting
*x_loop_stack
;
350 /* Chain of all pending case or switch statements. */
351 struct nesting
*x_case_stack
;
353 /* Separate chain including all of the above,
354 chained through the `all' field. */
355 struct nesting
*x_nesting_stack
;
357 /* Number of entries on nesting_stack now. */
360 /* Number of binding contours started so far in this function. */
361 int x_block_start_count
;
363 /* Each time we expand an expression-statement,
364 record the expr's type and its RTL value here. */
365 tree x_last_expr_type
;
366 rtx x_last_expr_value
;
368 /* Nonzero if within a ({...}) grouping, in which case we must
369 always compute a value for each expr-stmt in case it is the last one. */
370 int x_expr_stmts_for_value
;
372 /* Filename and line number of last line-number note,
373 whether we actually emitted it or not. */
374 const char *x_emit_filename
;
377 struct goto_fixup
*x_goto_fixup_chain
;
380 #define block_stack (cfun->stmt->x_block_stack)
381 #define stack_block_stack (cfun->stmt->x_stack_block_stack)
382 #define cond_stack (cfun->stmt->x_cond_stack)
383 #define loop_stack (cfun->stmt->x_loop_stack)
384 #define case_stack (cfun->stmt->x_case_stack)
385 #define nesting_stack (cfun->stmt->x_nesting_stack)
386 #define nesting_depth (cfun->stmt->x_nesting_depth)
387 #define current_block_start_count (cfun->stmt->x_block_start_count)
388 #define last_expr_type (cfun->stmt->x_last_expr_type)
389 #define last_expr_value (cfun->stmt->x_last_expr_value)
390 #define expr_stmts_for_value (cfun->stmt->x_expr_stmts_for_value)
391 #define emit_filename (cfun->stmt->x_emit_filename)
392 #define emit_lineno (cfun->stmt->x_emit_lineno)
393 #define goto_fixup_chain (cfun->stmt->x_goto_fixup_chain)
395 /* Non-zero if we are using EH to handle cleanus. */
396 static int using_eh_for_cleanups_p
= 0;
398 static int n_occurrences
PARAMS ((int, const char *));
399 static void expand_goto_internal
PARAMS ((tree
, rtx
, rtx
));
400 static int expand_fixup
PARAMS ((tree
, rtx
, rtx
));
401 static rtx expand_nl_handler_label
PARAMS ((rtx
, rtx
));
402 static void expand_nl_goto_receiver
PARAMS ((void));
403 static void expand_nl_goto_receivers
PARAMS ((struct nesting
*));
404 static void fixup_gotos
PARAMS ((struct nesting
*, rtx
, tree
,
406 static void expand_null_return_1
PARAMS ((rtx
, int));
407 static void expand_value_return
PARAMS ((rtx
));
408 static int tail_recursion_args
PARAMS ((tree
, tree
));
409 static void expand_cleanups
PARAMS ((tree
, tree
, int, int));
410 static void check_seenlabel
PARAMS ((void));
411 static void do_jump_if_equal
PARAMS ((rtx
, rtx
, rtx
, int));
412 static int estimate_case_costs
PARAMS ((case_node_ptr
));
413 static void group_case_nodes
PARAMS ((case_node_ptr
));
414 static void balance_case_nodes
PARAMS ((case_node_ptr
*,
416 static int node_has_low_bound
PARAMS ((case_node_ptr
, tree
));
417 static int node_has_high_bound
PARAMS ((case_node_ptr
, tree
));
418 static int node_is_bounded
PARAMS ((case_node_ptr
, tree
));
419 static void emit_jump_if_reachable
PARAMS ((rtx
));
420 static void emit_case_nodes
PARAMS ((rtx
, case_node_ptr
, rtx
, tree
));
421 static struct case_node
*case_tree2list
PARAMS ((case_node
*, case_node
*));
422 static void mark_cond_nesting
PARAMS ((struct nesting
*));
423 static void mark_loop_nesting
PARAMS ((struct nesting
*));
424 static void mark_block_nesting
PARAMS ((struct nesting
*));
425 static void mark_case_nesting
PARAMS ((struct nesting
*));
426 static void mark_case_node
PARAMS ((struct case_node
*));
427 static void mark_goto_fixup
PARAMS ((struct goto_fixup
*));
428 static void free_case_nodes
PARAMS ((case_node_ptr
));
431 using_eh_for_cleanups ()
433 using_eh_for_cleanups_p
= 1;
436 /* Mark N (known to be a cond-nesting) for GC. */
439 mark_cond_nesting (n
)
444 ggc_mark_rtx (n
->exit_label
);
445 ggc_mark_rtx (n
->data
.cond
.endif_label
);
446 ggc_mark_rtx (n
->data
.cond
.next_label
);
452 /* Mark N (known to be a loop-nesting) for GC. */
455 mark_loop_nesting (n
)
461 ggc_mark_rtx (n
->exit_label
);
462 ggc_mark_rtx (n
->data
.loop
.start_label
);
463 ggc_mark_rtx (n
->data
.loop
.end_label
);
464 ggc_mark_rtx (n
->data
.loop
.alt_end_label
);
465 ggc_mark_rtx (n
->data
.loop
.continue_label
);
471 /* Mark N (known to be a block-nesting) for GC. */
474 mark_block_nesting (n
)
479 struct label_chain
*l
;
481 ggc_mark_rtx (n
->exit_label
);
482 ggc_mark_rtx (n
->data
.block
.stack_level
);
483 ggc_mark_rtx (n
->data
.block
.first_insn
);
484 ggc_mark_tree (n
->data
.block
.cleanups
);
485 ggc_mark_tree (n
->data
.block
.outer_cleanups
);
487 for (l
= n
->data
.block
.label_chain
; l
!= NULL
; l
= l
->next
)
490 ggc_mark_tree (l
->label
);
493 ggc_mark_rtx (n
->data
.block
.last_unconditional_cleanup
);
495 /* ??? cleanup_ptr never points outside the stack, does it? */
501 /* Mark N (known to be a case-nesting) for GC. */
504 mark_case_nesting (n
)
509 ggc_mark_rtx (n
->exit_label
);
510 ggc_mark_rtx (n
->data
.case_stmt
.start
);
512 ggc_mark_tree (n
->data
.case_stmt
.default_label
);
513 ggc_mark_tree (n
->data
.case_stmt
.index_expr
);
514 ggc_mark_tree (n
->data
.case_stmt
.nominal_type
);
516 mark_case_node (n
->data
.case_stmt
.case_list
);
529 ggc_mark_tree (c
->low
);
530 ggc_mark_tree (c
->high
);
531 ggc_mark_tree (c
->code_label
);
533 mark_case_node (c
->right
);
534 mark_case_node (c
->left
);
542 struct goto_fixup
*g
;
547 ggc_mark_rtx (g
->before_jump
);
548 ggc_mark_tree (g
->target
);
549 ggc_mark_tree (g
->context
);
550 ggc_mark_rtx (g
->target_rtl
);
551 ggc_mark_rtx (g
->stack_level
);
552 ggc_mark_tree (g
->cleanup_list_list
);
558 /* Clear out all parts of the state in F that can safely be discarded
559 after the function has been compiled, to let garbage collection
560 reclaim the memory. */
566 /* We're about to free the function obstack. If we hold pointers to
567 things allocated there, then we'll try to mark them when we do
568 GC. So, we clear them out here explicitly. */
578 struct stmt_status
*p
;
583 mark_block_nesting (p
->x_block_stack
);
584 mark_cond_nesting (p
->x_cond_stack
);
585 mark_loop_nesting (p
->x_loop_stack
);
586 mark_case_nesting (p
->x_case_stack
);
588 ggc_mark_tree (p
->x_last_expr_type
);
589 /* last_epxr_value is only valid if last_expr_type is nonzero. */
590 if (p
->x_last_expr_type
)
591 ggc_mark_rtx (p
->x_last_expr_value
);
593 mark_goto_fixup (p
->x_goto_fixup_chain
);
599 gcc_obstack_init (&stmt_obstack
);
603 init_stmt_for_function ()
605 cfun
->stmt
= (struct stmt_status
*) xmalloc (sizeof (struct stmt_status
));
607 /* We are not currently within any block, conditional, loop or case. */
609 stack_block_stack
= 0;
616 current_block_start_count
= 0;
618 /* No gotos have been expanded yet. */
619 goto_fixup_chain
= 0;
621 /* We are not processing a ({...}) grouping. */
622 expr_stmts_for_value
= 0;
624 last_expr_value
= NULL_RTX
;
627 /* Return nonzero if anything is pushed on the loop, condition, or case
632 return cond_stack
|| loop_stack
|| case_stack
;
635 /* Record the current file and line. Called from emit_line_note. */
637 set_file_and_line_for_stmt (file
, line
)
641 /* If we're outputting an inline function, and we add a line note,
642 there may be no CFUN->STMT information. So, there's no need to
646 emit_filename
= file
;
651 /* Emit a no-op instruction. */
658 last_insn
= get_last_insn ();
660 && (GET_CODE (last_insn
) == CODE_LABEL
661 || (GET_CODE (last_insn
) == NOTE
662 && prev_real_insn (last_insn
) == 0)))
663 emit_insn (gen_nop ());
666 /* Return the rtx-label that corresponds to a LABEL_DECL,
667 creating it if necessary. */
673 if (TREE_CODE (label
) != LABEL_DECL
)
676 if (!DECL_RTL_SET_P (label
))
677 SET_DECL_RTL (label
, gen_label_rtx ());
679 return DECL_RTL (label
);
683 /* Add an unconditional jump to LABEL as the next sequential instruction. */
689 do_pending_stack_adjust ();
690 emit_jump_insn (gen_jump (label
));
694 /* Emit code to jump to the address
695 specified by the pointer expression EXP. */
698 expand_computed_goto (exp
)
701 rtx x
= expand_expr (exp
, NULL_RTX
, VOIDmode
, 0);
703 #ifdef POINTERS_EXTEND_UNSIGNED
704 x
= convert_memory_address (Pmode
, x
);
708 /* Be sure the function is executable. */
709 if (current_function_check_memory_usage
)
710 emit_library_call (chkr_check_exec_libfunc
, LCT_CONST_MAKE_BLOCK
,
711 VOIDmode
, 1, x
, ptr_mode
);
713 do_pending_stack_adjust ();
714 emit_indirect_jump (x
);
716 current_function_has_computed_jump
= 1;
719 /* Handle goto statements and the labels that they can go to. */
721 /* Specify the location in the RTL code of a label LABEL,
722 which is a LABEL_DECL tree node.
724 This is used for the kind of label that the user can jump to with a
725 goto statement, and for alternatives of a switch or case statement.
726 RTL labels generated for loops and conditionals don't go through here;
727 they are generated directly at the RTL level, by other functions below.
729 Note that this has nothing to do with defining label *names*.
730 Languages vary in how they do that and what that even means. */
736 struct label_chain
*p
;
738 do_pending_stack_adjust ();
739 emit_label (label_rtx (label
));
740 if (DECL_NAME (label
))
741 LABEL_NAME (DECL_RTL (label
)) = IDENTIFIER_POINTER (DECL_NAME (label
));
743 if (stack_block_stack
!= 0)
745 p
= (struct label_chain
*) ggc_alloc (sizeof (struct label_chain
));
746 p
->next
= stack_block_stack
->data
.block
.label_chain
;
747 stack_block_stack
->data
.block
.label_chain
= p
;
752 /* Declare that LABEL (a LABEL_DECL) may be used for nonlocal gotos
753 from nested functions. */
756 declare_nonlocal_label (label
)
759 rtx slot
= assign_stack_local (Pmode
, GET_MODE_SIZE (Pmode
), 0);
761 nonlocal_labels
= tree_cons (NULL_TREE
, label
, nonlocal_labels
);
762 LABEL_PRESERVE_P (label_rtx (label
)) = 1;
763 if (nonlocal_goto_handler_slots
== 0)
765 emit_stack_save (SAVE_NONLOCAL
,
766 &nonlocal_goto_stack_level
,
767 PREV_INSN (tail_recursion_reentry
));
769 nonlocal_goto_handler_slots
770 = gen_rtx_EXPR_LIST (VOIDmode
, slot
, nonlocal_goto_handler_slots
);
773 /* Generate RTL code for a `goto' statement with target label LABEL.
774 LABEL should be a LABEL_DECL tree node that was or will later be
775 defined with `expand_label'. */
783 /* Check for a nonlocal goto to a containing function. */
784 context
= decl_function_context (label
);
785 if (context
!= 0 && context
!= current_function_decl
)
787 struct function
*p
= find_function_data (context
);
788 rtx label_ref
= gen_rtx_LABEL_REF (Pmode
, label_rtx (label
));
789 rtx handler_slot
, static_chain
, save_area
, insn
;
792 /* Find the corresponding handler slot for this label. */
793 handler_slot
= p
->x_nonlocal_goto_handler_slots
;
794 for (link
= p
->x_nonlocal_labels
; TREE_VALUE (link
) != label
;
795 link
= TREE_CHAIN (link
))
796 handler_slot
= XEXP (handler_slot
, 1);
797 handler_slot
= XEXP (handler_slot
, 0);
799 p
->has_nonlocal_label
= 1;
800 current_function_has_nonlocal_goto
= 1;
801 LABEL_REF_NONLOCAL_P (label_ref
) = 1;
803 /* Copy the rtl for the slots so that they won't be shared in
804 case the virtual stack vars register gets instantiated differently
805 in the parent than in the child. */
807 static_chain
= copy_to_reg (lookup_static_chain (label
));
809 /* Get addr of containing function's current nonlocal goto handler,
810 which will do any cleanups and then jump to the label. */
811 handler_slot
= copy_to_reg (replace_rtx (copy_rtx (handler_slot
),
812 virtual_stack_vars_rtx
,
815 /* Get addr of containing function's nonlocal save area. */
816 save_area
= p
->x_nonlocal_goto_stack_level
;
818 save_area
= replace_rtx (copy_rtx (save_area
),
819 virtual_stack_vars_rtx
, static_chain
);
821 #if HAVE_nonlocal_goto
822 if (HAVE_nonlocal_goto
)
823 emit_insn (gen_nonlocal_goto (static_chain
, handler_slot
,
824 save_area
, label_ref
));
828 /* Restore frame pointer for containing function.
829 This sets the actual hard register used for the frame pointer
830 to the location of the function's incoming static chain info.
831 The non-local goto handler will then adjust it to contain the
832 proper value and reload the argument pointer, if needed. */
833 emit_move_insn (hard_frame_pointer_rtx
, static_chain
);
834 emit_stack_restore (SAVE_NONLOCAL
, save_area
, NULL_RTX
);
836 /* USE of hard_frame_pointer_rtx added for consistency;
837 not clear if really needed. */
838 emit_insn (gen_rtx_USE (VOIDmode
, hard_frame_pointer_rtx
));
839 emit_insn (gen_rtx_USE (VOIDmode
, stack_pointer_rtx
));
840 emit_indirect_jump (handler_slot
);
843 /* Search backwards to the jump insn and mark it as a
845 for (insn
= get_last_insn ();
846 GET_CODE (insn
) != JUMP_INSN
;
847 insn
= PREV_INSN (insn
))
849 REG_NOTES (insn
) = alloc_EXPR_LIST (REG_NON_LOCAL_GOTO
, const0_rtx
,
853 expand_goto_internal (label
, label_rtx (label
), NULL_RTX
);
856 /* Generate RTL code for a `goto' statement with target label BODY.
857 LABEL should be a LABEL_REF.
858 LAST_INSN, if non-0, is the rtx we should consider as the last
859 insn emitted (for the purposes of cleaning up a return). */
862 expand_goto_internal (body
, label
, last_insn
)
867 struct nesting
*block
;
870 if (GET_CODE (label
) != CODE_LABEL
)
873 /* If label has already been defined, we can tell now
874 whether and how we must alter the stack level. */
876 if (PREV_INSN (label
) != 0)
878 /* Find the innermost pending block that contains the label.
879 (Check containment by comparing insn-uids.)
880 Then restore the outermost stack level within that block,
881 and do cleanups of all blocks contained in it. */
882 for (block
= block_stack
; block
; block
= block
->next
)
884 if (INSN_UID (block
->data
.block
.first_insn
) < INSN_UID (label
))
886 if (block
->data
.block
.stack_level
!= 0)
887 stack_level
= block
->data
.block
.stack_level
;
888 /* Execute the cleanups for blocks we are exiting. */
889 if (block
->data
.block
.cleanups
!= 0)
891 expand_cleanups (block
->data
.block
.cleanups
, NULL_TREE
, 1, 1);
892 do_pending_stack_adjust ();
898 /* Ensure stack adjust isn't done by emit_jump, as this
899 would clobber the stack pointer. This one should be
900 deleted as dead by flow. */
901 clear_pending_stack_adjust ();
902 do_pending_stack_adjust ();
904 /* Don't do this adjust if it's to the end label and this function
905 is to return with a depressed stack pointer. */
906 if (label
== return_label
907 && (((TREE_CODE (TREE_TYPE (current_function_decl
))
909 && (TYPE_RETURNS_STACK_DEPRESSED
910 (TREE_TYPE (current_function_decl
))))))
913 emit_stack_restore (SAVE_BLOCK
, stack_level
, NULL_RTX
);
916 if (body
!= 0 && DECL_TOO_LATE (body
))
917 error ("jump to `%s' invalidly jumps into binding contour",
918 IDENTIFIER_POINTER (DECL_NAME (body
)));
920 /* Label not yet defined: may need to put this goto
921 on the fixup list. */
922 else if (! expand_fixup (body
, label
, last_insn
))
924 /* No fixup needed. Record that the label is the target
925 of at least one goto that has no fixup. */
927 TREE_ADDRESSABLE (body
) = 1;
933 /* Generate if necessary a fixup for a goto
934 whose target label in tree structure (if any) is TREE_LABEL
935 and whose target in rtl is RTL_LABEL.
937 If LAST_INSN is nonzero, we pretend that the jump appears
938 after insn LAST_INSN instead of at the current point in the insn stream.
940 The fixup will be used later to insert insns just before the goto.
941 Those insns will restore the stack level as appropriate for the
942 target label, and will (in the case of C++) also invoke any object
943 destructors which have to be invoked when we exit the scopes which
944 are exited by the goto.
946 Value is nonzero if a fixup is made. */
949 expand_fixup (tree_label
, rtl_label
, last_insn
)
954 struct nesting
*block
, *end_block
;
956 /* See if we can recognize which block the label will be output in.
957 This is possible in some very common cases.
958 If we succeed, set END_BLOCK to that block.
959 Otherwise, set it to 0. */
962 && (rtl_label
== cond_stack
->data
.cond
.endif_label
963 || rtl_label
== cond_stack
->data
.cond
.next_label
))
964 end_block
= cond_stack
;
965 /* If we are in a loop, recognize certain labels which
966 are likely targets. This reduces the number of fixups
967 we need to create. */
969 && (rtl_label
== loop_stack
->data
.loop
.start_label
970 || rtl_label
== loop_stack
->data
.loop
.end_label
971 || rtl_label
== loop_stack
->data
.loop
.continue_label
))
972 end_block
= loop_stack
;
976 /* Now set END_BLOCK to the binding level to which we will return. */
980 struct nesting
*next_block
= end_block
->all
;
983 /* First see if the END_BLOCK is inside the innermost binding level.
984 If so, then no cleanups or stack levels are relevant. */
985 while (next_block
&& next_block
!= block
)
986 next_block
= next_block
->all
;
991 /* Otherwise, set END_BLOCK to the innermost binding level
992 which is outside the relevant control-structure nesting. */
993 next_block
= block_stack
->next
;
994 for (block
= block_stack
; block
!= end_block
; block
= block
->all
)
995 if (block
== next_block
)
996 next_block
= next_block
->next
;
997 end_block
= next_block
;
1000 /* Does any containing block have a stack level or cleanups?
1001 If not, no fixup is needed, and that is the normal case
1002 (the only case, for standard C). */
1003 for (block
= block_stack
; block
!= end_block
; block
= block
->next
)
1004 if (block
->data
.block
.stack_level
!= 0
1005 || block
->data
.block
.cleanups
!= 0)
1008 if (block
!= end_block
)
1010 /* Ok, a fixup is needed. Add a fixup to the list of such. */
1011 struct goto_fixup
*fixup
1012 = (struct goto_fixup
*) ggc_alloc (sizeof (struct goto_fixup
));
1013 /* In case an old stack level is restored, make sure that comes
1014 after any pending stack adjust. */
1015 /* ?? If the fixup isn't to come at the present position,
1016 doing the stack adjust here isn't useful. Doing it with our
1017 settings at that location isn't useful either. Let's hope
1020 do_pending_stack_adjust ();
1021 fixup
->target
= tree_label
;
1022 fixup
->target_rtl
= rtl_label
;
1024 /* Create a BLOCK node and a corresponding matched set of
1025 NOTE_INSN_BLOCK_BEG and NOTE_INSN_BLOCK_END notes at
1026 this point. The notes will encapsulate any and all fixup
1027 code which we might later insert at this point in the insn
1028 stream. Also, the BLOCK node will be the parent (i.e. the
1029 `SUPERBLOCK') of any other BLOCK nodes which we might create
1030 later on when we are expanding the fixup code.
1032 Note that optimization passes (including expand_end_loop)
1033 might move the *_BLOCK notes away, so we use a NOTE_INSN_DELETED
1034 as a placeholder. */
1037 register rtx original_before_jump
1038 = last_insn
? last_insn
: get_last_insn ();
1043 block
= make_node (BLOCK
);
1044 TREE_USED (block
) = 1;
1046 if (!cfun
->x_whole_function_mode_p
)
1047 insert_block (block
);
1051 = BLOCK_CHAIN (DECL_INITIAL (current_function_decl
));
1052 BLOCK_CHAIN (DECL_INITIAL (current_function_decl
))
1057 start
= emit_note (NULL
, NOTE_INSN_BLOCK_BEG
);
1058 if (cfun
->x_whole_function_mode_p
)
1059 NOTE_BLOCK (start
) = block
;
1060 fixup
->before_jump
= emit_note (NULL
, NOTE_INSN_DELETED
);
1061 end
= emit_note (NULL
, NOTE_INSN_BLOCK_END
);
1062 if (cfun
->x_whole_function_mode_p
)
1063 NOTE_BLOCK (end
) = block
;
1064 fixup
->context
= block
;
1066 emit_insns_after (start
, original_before_jump
);
1069 fixup
->block_start_count
= current_block_start_count
;
1070 fixup
->stack_level
= 0;
1071 fixup
->cleanup_list_list
1072 = ((block
->data
.block
.outer_cleanups
1073 || block
->data
.block
.cleanups
)
1074 ? tree_cons (NULL_TREE
, block
->data
.block
.cleanups
,
1075 block
->data
.block
.outer_cleanups
)
1077 fixup
->next
= goto_fixup_chain
;
1078 goto_fixup_chain
= fixup
;
1084 /* Expand any needed fixups in the outputmost binding level of the
1085 function. FIRST_INSN is the first insn in the function. */
1088 expand_fixups (first_insn
)
1091 fixup_gotos (NULL
, NULL_RTX
, NULL_TREE
, first_insn
, 0);
1094 /* When exiting a binding contour, process all pending gotos requiring fixups.
1095 THISBLOCK is the structure that describes the block being exited.
1096 STACK_LEVEL is the rtx for the stack level to restore exiting this contour.
1097 CLEANUP_LIST is a list of expressions to evaluate on exiting this contour.
1098 FIRST_INSN is the insn that began this contour.
1100 Gotos that jump out of this contour must restore the
1101 stack level and do the cleanups before actually jumping.
1103 DONT_JUMP_IN nonzero means report error there is a jump into this
1104 contour from before the beginning of the contour.
1105 This is also done if STACK_LEVEL is nonzero. */
1108 fixup_gotos (thisblock
, stack_level
, cleanup_list
, first_insn
, dont_jump_in
)
1109 struct nesting
*thisblock
;
1115 register struct goto_fixup
*f
, *prev
;
1117 /* F is the fixup we are considering; PREV is the previous one. */
1118 /* We run this loop in two passes so that cleanups of exited blocks
1119 are run first, and blocks that are exited are marked so
1122 for (prev
= 0, f
= goto_fixup_chain
; f
; prev
= f
, f
= f
->next
)
1124 /* Test for a fixup that is inactive because it is already handled. */
1125 if (f
->before_jump
== 0)
1127 /* Delete inactive fixup from the chain, if that is easy to do. */
1129 prev
->next
= f
->next
;
1131 /* Has this fixup's target label been defined?
1132 If so, we can finalize it. */
1133 else if (PREV_INSN (f
->target_rtl
) != 0)
1135 register rtx cleanup_insns
;
1137 /* If this fixup jumped into this contour from before the beginning
1138 of this contour, report an error. This code used to use
1139 the first non-label insn after f->target_rtl, but that's
1140 wrong since such can be added, by things like put_var_into_stack
1141 and have INSN_UIDs that are out of the range of the block. */
1142 /* ??? Bug: this does not detect jumping in through intermediate
1143 blocks that have stack levels or cleanups.
1144 It detects only a problem with the innermost block
1145 around the label. */
1147 && (dont_jump_in
|| stack_level
|| cleanup_list
)
1148 && INSN_UID (first_insn
) < INSN_UID (f
->target_rtl
)
1149 && INSN_UID (first_insn
) > INSN_UID (f
->before_jump
)
1150 && ! DECL_ERROR_ISSUED (f
->target
))
1152 error_with_decl (f
->target
,
1153 "label `%s' used before containing binding contour");
1154 /* Prevent multiple errors for one label. */
1155 DECL_ERROR_ISSUED (f
->target
) = 1;
1158 /* We will expand the cleanups into a sequence of their own and
1159 then later on we will attach this new sequence to the insn
1160 stream just ahead of the actual jump insn. */
1164 /* Temporarily restore the lexical context where we will
1165 logically be inserting the fixup code. We do this for the
1166 sake of getting the debugging information right. */
1169 set_block (f
->context
);
1171 /* Expand the cleanups for blocks this jump exits. */
1172 if (f
->cleanup_list_list
)
1175 for (lists
= f
->cleanup_list_list
; lists
; lists
= TREE_CHAIN (lists
))
1176 /* Marked elements correspond to blocks that have been closed.
1177 Do their cleanups. */
1178 if (TREE_ADDRESSABLE (lists
)
1179 && TREE_VALUE (lists
) != 0)
1181 expand_cleanups (TREE_VALUE (lists
), NULL_TREE
, 1, 1);
1182 /* Pop any pushes done in the cleanups,
1183 in case function is about to return. */
1184 do_pending_stack_adjust ();
1188 /* Restore stack level for the biggest contour that this
1189 jump jumps out of. */
1191 && ! (f
->target_rtl
== return_label
1192 && ((TREE_CODE (TREE_TYPE (current_function_decl
))
1194 && (TYPE_RETURNS_STACK_DEPRESSED
1195 (TREE_TYPE (current_function_decl
))))))
1196 emit_stack_restore (SAVE_BLOCK
, f
->stack_level
, f
->before_jump
);
1198 /* Finish up the sequence containing the insns which implement the
1199 necessary cleanups, and then attach that whole sequence to the
1200 insn stream just ahead of the actual jump insn. Attaching it
1201 at that point insures that any cleanups which are in fact
1202 implicit C++ object destructions (which must be executed upon
1203 leaving the block) appear (to the debugger) to be taking place
1204 in an area of the generated code where the object(s) being
1205 destructed are still "in scope". */
1207 cleanup_insns
= get_insns ();
1211 emit_insns_after (cleanup_insns
, f
->before_jump
);
1217 /* For any still-undefined labels, do the cleanups for this block now.
1218 We must do this now since items in the cleanup list may go out
1219 of scope when the block ends. */
1220 for (prev
= 0, f
= goto_fixup_chain
; f
; prev
= f
, f
= f
->next
)
1221 if (f
->before_jump
!= 0
1222 && PREV_INSN (f
->target_rtl
) == 0
1223 /* Label has still not appeared. If we are exiting a block with
1224 a stack level to restore, that started before the fixup,
1225 mark this stack level as needing restoration
1226 when the fixup is later finalized. */
1228 /* Note: if THISBLOCK == 0 and we have a label that hasn't appeared, it
1229 means the label is undefined. That's erroneous, but possible. */
1230 && (thisblock
->data
.block
.block_start_count
1231 <= f
->block_start_count
))
1233 tree lists
= f
->cleanup_list_list
;
1236 for (; lists
; lists
= TREE_CHAIN (lists
))
1237 /* If the following elt. corresponds to our containing block
1238 then the elt. must be for this block. */
1239 if (TREE_CHAIN (lists
) == thisblock
->data
.block
.outer_cleanups
)
1243 set_block (f
->context
);
1244 expand_cleanups (TREE_VALUE (lists
), NULL_TREE
, 1, 1);
1245 do_pending_stack_adjust ();
1246 cleanup_insns
= get_insns ();
1249 if (cleanup_insns
!= 0)
1251 = emit_insns_after (cleanup_insns
, f
->before_jump
);
1253 f
->cleanup_list_list
= TREE_CHAIN (lists
);
1257 f
->stack_level
= stack_level
;
1261 /* Return the number of times character C occurs in string S. */
1263 n_occurrences (c
, s
)
1273 /* Generate RTL for an asm statement (explicit assembler code).
1274 BODY is a STRING_CST node containing the assembler code text,
1275 or an ADDR_EXPR containing a STRING_CST. */
1281 if (current_function_check_memory_usage
)
1283 error ("`asm' cannot be used in function where memory usage is checked");
1287 if (TREE_CODE (body
) == ADDR_EXPR
)
1288 body
= TREE_OPERAND (body
, 0);
1290 emit_insn (gen_rtx_ASM_INPUT (VOIDmode
,
1291 TREE_STRING_POINTER (body
)));
1295 /* Parse the output constraint pointed to by *CONSTRAINT_P. It is the
1296 OPERAND_NUMth output operand, indexed from zero. There are NINPUTS
1297 inputs and NOUTPUTS outputs to this extended-asm. Upon return,
1298 *ALLOWS_MEM will be TRUE iff the constraint allows the use of a
1299 memory operand. Similarly, *ALLOWS_REG will be TRUE iff the
1300 constraint allows the use of a register operand. And, *IS_INOUT
1301 will be true if the operand is read-write, i.e., if it is used as
1302 an input as well as an output. If *CONSTRAINT_P is not in
1303 canonical form, it will be made canonical. (Note that `+' will be
1304 rpelaced with `=' as part of this process.)
1306 Returns TRUE if all went well; FALSE if an error occurred. */
1309 parse_output_constraint (constraint_p
,
1316 const char **constraint_p
;
1324 const char *constraint
= *constraint_p
;
1327 /* Assume the constraint doesn't allow the use of either a register
1329 *allows_mem
= false;
1330 *allows_reg
= false;
1332 /* Allow the `=' or `+' to not be at the beginning of the string,
1333 since it wasn't explicitly documented that way, and there is a
1334 large body of code that puts it last. Swap the character to
1335 the front, so as not to uglify any place else. */
1336 p
= strchr (constraint
, '=');
1338 p
= strchr (constraint
, '+');
1340 /* If the string doesn't contain an `=', issue an error
1344 error ("output operand constraint lacks `='");
1348 /* If the constraint begins with `+', then the operand is both read
1349 from and written to. */
1350 *is_inout
= (*p
== '+');
1352 /* Make sure we can specify the matching operand. */
1353 if (*is_inout
&& operand_num
> 9)
1355 error ("output operand constraint %d contains `+'",
1360 /* Canonicalize the output constraint so that it begins with `='. */
1361 if (p
!= constraint
|| is_inout
)
1364 size_t c_len
= strlen (constraint
);
1366 if (p
!= constraint
)
1367 warning ("output constraint `%c' for operand %d is not at the beginning",
1370 /* Make a copy of the constraint. */
1371 buf
= alloca (c_len
+ 1);
1372 strcpy (buf
, constraint
);
1373 /* Swap the first character and the `=' or `+'. */
1374 buf
[p
- constraint
] = buf
[0];
1375 /* Make sure the first character is an `='. (Until we do this,
1376 it might be a `+'.) */
1378 /* Replace the constraint with the canonicalized string. */
1379 *constraint_p
= ggc_alloc_string (buf
, c_len
);
1380 constraint
= *constraint_p
;
1383 /* Loop through the constraint string. */
1384 for (p
= constraint
+ 1; *p
; ++p
)
1389 error ("operand constraint contains '+' or '=' at illegal position.");
1393 if (operand_num
+ 1 == ninputs
+ noutputs
)
1395 error ("`%%' constraint used with last operand");
1400 case 'V': case 'm': case 'o':
1404 case '?': case '!': case '*': case '&': case '#':
1405 case 'E': case 'F': case 'G': case 'H':
1406 case 's': case 'i': case 'n':
1407 case 'I': case 'J': case 'K': case 'L': case 'M':
1408 case 'N': case 'O': case 'P': case ',':
1411 case '0': case '1': case '2': case '3': case '4':
1412 case '5': case '6': case '7': case '8': case '9':
1413 error ("matching constraint not valid in output operand");
1417 /* ??? Before flow, auto inc/dec insns are not supposed to exist,
1418 excepting those that expand_call created. So match memory
1435 if (REG_CLASS_FROM_LETTER (*p
) != NO_REGS
)
1437 #ifdef EXTRA_CONSTRAINT
1440 /* Otherwise we can't assume anything about the nature of
1441 the constraint except that it isn't purely registers.
1442 Treat it like "g" and hope for the best. */
1453 /* Generate RTL for an asm statement with arguments.
1454 STRING is the instruction template.
1455 OUTPUTS is a list of output arguments (lvalues); INPUTS a list of inputs.
1456 Each output or input has an expression in the TREE_VALUE and
1457 a constraint-string in the TREE_PURPOSE.
1458 CLOBBERS is a list of STRING_CST nodes each naming a hard register
1459 that is clobbered by this insn.
1461 Not all kinds of lvalue that may appear in OUTPUTS can be stored directly.
1462 Some elements of OUTPUTS may be replaced with trees representing temporary
1463 values. The caller should copy those temporary values to the originally
1466 VOL nonzero means the insn is volatile; don't optimize it. */
1469 expand_asm_operands (string
, outputs
, inputs
, clobbers
, vol
, filename
, line
)
1470 tree string
, outputs
, inputs
, clobbers
;
1472 const char *filename
;
1475 rtvec argvec
, constraints
;
1477 int ninputs
= list_length (inputs
);
1478 int noutputs
= list_length (outputs
);
1483 /* Vector of RTX's of evaluated output operands. */
1484 rtx
*output_rtx
= (rtx
*) alloca (noutputs
* sizeof (rtx
));
1485 int *inout_opnum
= (int *) alloca (noutputs
* sizeof (int));
1486 rtx
*real_output_rtx
= (rtx
*) alloca (noutputs
* sizeof (rtx
));
1487 enum machine_mode
*inout_mode
1488 = (enum machine_mode
*) alloca (noutputs
* sizeof (enum machine_mode
));
1489 const char **output_constraints
1490 = alloca (noutputs
* sizeof (const char *));
1491 /* The insn we have emitted. */
1493 int old_generating_concat_p
= generating_concat_p
;
1495 /* An ASM with no outputs needs to be treated as volatile, for now. */
1499 if (current_function_check_memory_usage
)
1501 error ("`asm' cannot be used with `-fcheck-memory-usage'");
1505 #ifdef MD_ASM_CLOBBERS
1506 /* Sometimes we wish to automatically clobber registers across an asm.
1507 Case in point is when the i386 backend moved from cc0 to a hard reg --
1508 maintaining source-level compatability means automatically clobbering
1509 the flags register. */
1510 MD_ASM_CLOBBERS (clobbers
);
1513 if (current_function_check_memory_usage
)
1515 error ("`asm' cannot be used in function where memory usage is checked");
1519 /* Count the number of meaningful clobbered registers, ignoring what
1520 we would ignore later. */
1522 for (tail
= clobbers
; tail
; tail
= TREE_CHAIN (tail
))
1524 const char *regname
= TREE_STRING_POINTER (TREE_VALUE (tail
));
1526 i
= decode_reg_name (regname
);
1527 if (i
>= 0 || i
== -4)
1530 error ("unknown register name `%s' in `asm'", regname
);
1535 /* Check that the number of alternatives is constant across all
1537 if (outputs
|| inputs
)
1539 tree tmp
= TREE_PURPOSE (outputs
? outputs
: inputs
);
1540 int nalternatives
= n_occurrences (',', TREE_STRING_POINTER (tmp
));
1543 if (nalternatives
+ 1 > MAX_RECOG_ALTERNATIVES
)
1545 error ("too many alternatives in `asm'");
1552 const char *constraint
= TREE_STRING_POINTER (TREE_PURPOSE (tmp
));
1554 if (n_occurrences (',', constraint
) != nalternatives
)
1556 error ("operand constraints for `asm' differ in number of alternatives");
1560 if (TREE_CHAIN (tmp
))
1561 tmp
= TREE_CHAIN (tmp
);
1563 tmp
= next
, next
= 0;
1567 for (i
= 0, tail
= outputs
; tail
; tail
= TREE_CHAIN (tail
), i
++)
1569 tree val
= TREE_VALUE (tail
);
1570 tree type
= TREE_TYPE (val
);
1571 const char *constraint
;
1576 /* If there's an erroneous arg, emit no insn. */
1577 if (type
== error_mark_node
)
1580 /* Make sure constraint has `=' and does not have `+'. Also, see
1581 if it allows any register. Be liberal on the latter test, since
1582 the worst that happens if we get it wrong is we issue an error
1585 constraint
= TREE_STRING_POINTER (TREE_PURPOSE (tail
));
1586 output_constraints
[i
] = constraint
;
1588 /* Try to parse the output constraint. If that fails, there's
1589 no point in going further. */
1590 if (!parse_output_constraint (&output_constraints
[i
],
1599 /* If an output operand is not a decl or indirect ref and our constraint
1600 allows a register, make a temporary to act as an intermediate.
1601 Make the asm insn write into that, then our caller will copy it to
1602 the real output operand. Likewise for promoted variables. */
1604 generating_concat_p
= 0;
1606 real_output_rtx
[i
] = NULL_RTX
;
1607 if ((TREE_CODE (val
) == INDIRECT_REF
1610 && (allows_mem
|| GET_CODE (DECL_RTL (val
)) == REG
)
1611 && ! (GET_CODE (DECL_RTL (val
)) == REG
1612 && GET_MODE (DECL_RTL (val
)) != TYPE_MODE (type
)))
1617 mark_addressable (TREE_VALUE (tail
));
1620 = expand_expr (TREE_VALUE (tail
), NULL_RTX
, VOIDmode
,
1621 EXPAND_MEMORY_USE_WO
);
1623 if (! allows_reg
&& GET_CODE (output_rtx
[i
]) != MEM
)
1624 error ("output number %d not directly addressable", i
);
1625 if ((! allows_mem
&& GET_CODE (output_rtx
[i
]) == MEM
)
1626 || GET_CODE (output_rtx
[i
]) == CONCAT
)
1628 real_output_rtx
[i
] = protect_from_queue (output_rtx
[i
], 1);
1629 output_rtx
[i
] = gen_reg_rtx (GET_MODE (output_rtx
[i
]));
1631 emit_move_insn (output_rtx
[i
], real_output_rtx
[i
]);
1636 output_rtx
[i
] = assign_temp (type
, 0, 0, 1);
1637 TREE_VALUE (tail
) = make_tree (type
, output_rtx
[i
]);
1640 generating_concat_p
= old_generating_concat_p
;
1644 inout_mode
[ninout
] = TYPE_MODE (TREE_TYPE (TREE_VALUE (tail
)));
1645 inout_opnum
[ninout
++] = i
;
1650 if (ninputs
+ noutputs
> MAX_RECOG_OPERANDS
)
1652 error ("more than %d operands in `asm'", MAX_RECOG_OPERANDS
);
1656 /* Make vectors for the expression-rtx and constraint strings. */
1658 argvec
= rtvec_alloc (ninputs
);
1659 constraints
= rtvec_alloc (ninputs
);
1661 body
= gen_rtx_ASM_OPERANDS ((noutputs
== 0 ? VOIDmode
1662 : GET_MODE (output_rtx
[0])),
1663 TREE_STRING_POINTER (string
),
1664 empty_string
, 0, argvec
, constraints
,
1667 MEM_VOLATILE_P (body
) = vol
;
1669 /* Eval the inputs and put them into ARGVEC.
1670 Put their constraints into ASM_INPUTs and store in CONSTRAINTS. */
1673 for (tail
= inputs
; tail
; tail
= TREE_CHAIN (tail
))
1676 int allows_reg
= 0, allows_mem
= 0;
1677 const char *constraint
, *orig_constraint
;
1681 /* If there's an erroneous arg, emit no insn,
1682 because the ASM_INPUT would get VOIDmode
1683 and that could cause a crash in reload. */
1684 if (TREE_TYPE (TREE_VALUE (tail
)) == error_mark_node
)
1687 /* ??? Can this happen, and does the error message make any sense? */
1688 if (TREE_PURPOSE (tail
) == NULL_TREE
)
1690 error ("hard register `%s' listed as input operand to `asm'",
1691 TREE_STRING_POINTER (TREE_VALUE (tail
)) );
1695 constraint
= TREE_STRING_POINTER (TREE_PURPOSE (tail
));
1696 c_len
= strlen (constraint
);
1697 orig_constraint
= constraint
;
1699 /* Make sure constraint has neither `=', `+', nor '&'. */
1701 for (j
= 0; j
< c_len
; j
++)
1702 switch (constraint
[j
])
1704 case '+': case '=': case '&':
1705 if (constraint
== orig_constraint
)
1707 error ("input operand constraint contains `%c'",
1714 if (constraint
== orig_constraint
1715 && i
+ 1 == ninputs
- ninout
)
1717 error ("`%%' constraint used with last operand");
1722 case 'V': case 'm': case 'o':
1727 case '?': case '!': case '*': case '#':
1728 case 'E': case 'F': case 'G': case 'H':
1729 case 's': case 'i': case 'n':
1730 case 'I': case 'J': case 'K': case 'L': case 'M':
1731 case 'N': case 'O': case 'P': case ',':
1734 /* Whether or not a numeric constraint allows a register is
1735 decided by the matching constraint, and so there is no need
1736 to do anything special with them. We must handle them in
1737 the default case, so that we don't unnecessarily force
1738 operands to memory. */
1739 case '0': case '1': case '2': case '3': case '4':
1740 case '5': case '6': case '7': case '8': case '9':
1741 if (constraint
[j
] >= '0' + noutputs
)
1744 ("matching constraint references invalid operand number");
1748 /* Try and find the real constraint for this dup. */
1749 if ((j
== 0 && c_len
== 1)
1750 || (j
== 1 && c_len
== 2 && constraint
[0] == '%'))
1754 for (j
= constraint
[j
] - '0'; j
> 0; --j
)
1757 constraint
= TREE_STRING_POINTER (TREE_PURPOSE (o
));
1758 c_len
= strlen (constraint
);
1775 if (! ISALPHA (constraint
[j
]))
1777 error ("invalid punctuation `%c' in constraint",
1781 if (REG_CLASS_FROM_LETTER (constraint
[j
]) != NO_REGS
)
1783 #ifdef EXTRA_CONSTRAINT
1786 /* Otherwise we can't assume anything about the nature of
1787 the constraint except that it isn't purely registers.
1788 Treat it like "g" and hope for the best. */
1796 if (! allows_reg
&& allows_mem
)
1797 mark_addressable (TREE_VALUE (tail
));
1799 op
= expand_expr (TREE_VALUE (tail
), NULL_RTX
, VOIDmode
, 0);
1801 /* Never pass a CONCAT to an ASM. */
1802 generating_concat_p
= 0;
1803 if (GET_CODE (op
) == CONCAT
)
1804 op
= force_reg (GET_MODE (op
), op
);
1806 if (asm_operand_ok (op
, constraint
) <= 0)
1809 op
= force_reg (TYPE_MODE (TREE_TYPE (TREE_VALUE (tail
))), op
);
1810 else if (!allows_mem
)
1811 warning ("asm operand %d probably doesn't match constraints", i
);
1812 else if (CONSTANT_P (op
))
1813 op
= force_const_mem (TYPE_MODE (TREE_TYPE (TREE_VALUE (tail
))),
1815 else if (GET_CODE (op
) == REG
1816 || GET_CODE (op
) == SUBREG
1817 || GET_CODE (op
) == ADDRESSOF
1818 || GET_CODE (op
) == CONCAT
)
1820 tree type
= TREE_TYPE (TREE_VALUE (tail
));
1821 tree qual_type
= build_qualified_type (type
,
1823 | TYPE_QUAL_CONST
));
1824 rtx memloc
= assign_temp (qual_type
, 1, 1, 1);
1826 emit_move_insn (memloc
, op
);
1830 else if (GET_CODE (op
) == MEM
&& MEM_VOLATILE_P (op
))
1831 /* We won't recognize volatile memory as available a
1832 memory_operand at this point. Ignore it. */
1834 else if (queued_subexp_p (op
))
1837 /* ??? Leave this only until we have experience with what
1838 happens in combine and elsewhere when constraints are
1840 warning ("asm operand %d probably doesn't match constraints", i
);
1842 generating_concat_p
= old_generating_concat_p
;
1843 ASM_OPERANDS_INPUT (body
, i
) = op
;
1845 ASM_OPERANDS_INPUT_CONSTRAINT_EXP (body
, i
)
1846 = gen_rtx_ASM_INPUT (TYPE_MODE (TREE_TYPE (TREE_VALUE (tail
))),
1851 /* Protect all the operands from the queue now that they have all been
1854 generating_concat_p
= 0;
1856 for (i
= 0; i
< ninputs
- ninout
; i
++)
1857 ASM_OPERANDS_INPUT (body
, i
)
1858 = protect_from_queue (ASM_OPERANDS_INPUT (body
, i
), 0);
1860 for (i
= 0; i
< noutputs
; i
++)
1861 output_rtx
[i
] = protect_from_queue (output_rtx
[i
], 1);
1863 /* For in-out operands, copy output rtx to input rtx. */
1864 for (i
= 0; i
< ninout
; i
++)
1866 int j
= inout_opnum
[i
];
1868 ASM_OPERANDS_INPUT (body
, ninputs
- ninout
+ i
)
1870 ASM_OPERANDS_INPUT_CONSTRAINT_EXP (body
, ninputs
- ninout
+ i
)
1871 = gen_rtx_ASM_INPUT (inout_mode
[i
], digit_string (j
));
1874 generating_concat_p
= old_generating_concat_p
;
1876 /* Now, for each output, construct an rtx
1877 (set OUTPUT (asm_operands INSN OUTPUTNUMBER OUTPUTCONSTRAINT
1878 ARGVEC CONSTRAINTS))
1879 If there is more than one, put them inside a PARALLEL. */
1881 if (noutputs
== 1 && nclobbers
== 0)
1883 ASM_OPERANDS_OUTPUT_CONSTRAINT (body
)
1884 = output_constraints
[0];
1885 insn
= emit_insn (gen_rtx_SET (VOIDmode
, output_rtx
[0], body
));
1888 else if (noutputs
== 0 && nclobbers
== 0)
1890 /* No output operands: put in a raw ASM_OPERANDS rtx. */
1891 insn
= emit_insn (body
);
1902 body
= gen_rtx_PARALLEL (VOIDmode
, rtvec_alloc (num
+ nclobbers
));
1904 /* For each output operand, store a SET. */
1905 for (i
= 0, tail
= outputs
; tail
; tail
= TREE_CHAIN (tail
), i
++)
1907 XVECEXP (body
, 0, i
)
1908 = gen_rtx_SET (VOIDmode
,
1910 gen_rtx_ASM_OPERANDS
1911 (GET_MODE (output_rtx
[i
]),
1912 TREE_STRING_POINTER (string
),
1913 output_constraints
[i
],
1914 i
, argvec
, constraints
,
1917 MEM_VOLATILE_P (SET_SRC (XVECEXP (body
, 0, i
))) = vol
;
1920 /* If there are no outputs (but there are some clobbers)
1921 store the bare ASM_OPERANDS into the PARALLEL. */
1924 XVECEXP (body
, 0, i
++) = obody
;
1926 /* Store (clobber REG) for each clobbered register specified. */
1928 for (tail
= clobbers
; tail
; tail
= TREE_CHAIN (tail
))
1930 const char *regname
= TREE_STRING_POINTER (TREE_VALUE (tail
));
1931 int j
= decode_reg_name (regname
);
1935 if (j
== -3) /* `cc', which is not a register */
1938 if (j
== -4) /* `memory', don't cache memory across asm */
1940 XVECEXP (body
, 0, i
++)
1941 = gen_rtx_CLOBBER (VOIDmode
,
1944 gen_rtx_SCRATCH (VOIDmode
)));
1948 /* Ignore unknown register, error already signaled. */
1952 /* Use QImode since that's guaranteed to clobber just one reg. */
1953 XVECEXP (body
, 0, i
++)
1954 = gen_rtx_CLOBBER (VOIDmode
, gen_rtx_REG (QImode
, j
));
1957 insn
= emit_insn (body
);
1960 /* For any outputs that needed reloading into registers, spill them
1961 back to where they belong. */
1962 for (i
= 0; i
< noutputs
; ++i
)
1963 if (real_output_rtx
[i
])
1964 emit_move_insn (real_output_rtx
[i
], output_rtx
[i
]);
1969 /* Generate RTL to evaluate the expression EXP
1970 and remember it in case this is the VALUE in a ({... VALUE; }) constr. */
1973 expand_expr_stmt (exp
)
1976 /* If -W, warn about statements with no side effects,
1977 except for an explicit cast to void (e.g. for assert()), and
1978 except inside a ({...}) where they may be useful. */
1979 if (expr_stmts_for_value
== 0 && exp
!= error_mark_node
)
1981 if (! TREE_SIDE_EFFECTS (exp
))
1983 if ((extra_warnings
|| warn_unused_value
)
1984 && !(TREE_CODE (exp
) == CONVERT_EXPR
1985 && VOID_TYPE_P (TREE_TYPE (exp
))))
1986 warning_with_file_and_line (emit_filename
, emit_lineno
,
1987 "statement with no effect");
1989 else if (warn_unused_value
)
1990 warn_if_unused_value (exp
);
1993 /* If EXP is of function type and we are expanding statements for
1994 value, convert it to pointer-to-function. */
1995 if (expr_stmts_for_value
&& TREE_CODE (TREE_TYPE (exp
)) == FUNCTION_TYPE
)
1996 exp
= build1 (ADDR_EXPR
, build_pointer_type (TREE_TYPE (exp
)), exp
);
1998 /* The call to `expand_expr' could cause last_expr_type and
1999 last_expr_value to get reset. Therefore, we set last_expr_value
2000 and last_expr_type *after* calling expand_expr. */
2001 last_expr_value
= expand_expr (exp
,
2002 (expr_stmts_for_value
2003 ? NULL_RTX
: const0_rtx
),
2005 last_expr_type
= TREE_TYPE (exp
);
2007 /* If all we do is reference a volatile value in memory,
2008 copy it to a register to be sure it is actually touched. */
2009 if (last_expr_value
!= 0 && GET_CODE (last_expr_value
) == MEM
2010 && TREE_THIS_VOLATILE (exp
))
2012 if (TYPE_MODE (TREE_TYPE (exp
)) == VOIDmode
)
2014 else if (TYPE_MODE (TREE_TYPE (exp
)) != BLKmode
)
2015 copy_to_reg (last_expr_value
);
2018 rtx lab
= gen_label_rtx ();
2020 /* Compare the value with itself to reference it. */
2021 emit_cmp_and_jump_insns (last_expr_value
, last_expr_value
, EQ
,
2022 expand_expr (TYPE_SIZE (last_expr_type
),
2023 NULL_RTX
, VOIDmode
, 0),
2025 TYPE_ALIGN (last_expr_type
) / BITS_PER_UNIT
,
2031 /* If this expression is part of a ({...}) and is in memory, we may have
2032 to preserve temporaries. */
2033 preserve_temp_slots (last_expr_value
);
2035 /* Free any temporaries used to evaluate this expression. Any temporary
2036 used as a result of this expression will already have been preserved
2043 /* Warn if EXP contains any computations whose results are not used.
2044 Return 1 if a warning is printed; 0 otherwise. */
2047 warn_if_unused_value (exp
)
2050 if (TREE_USED (exp
))
2053 /* Don't warn about void constructs. This includes casting to void,
2054 void function calls, and statement expressions with a final cast
2056 if (VOID_TYPE_P (TREE_TYPE (exp
)))
2059 /* If this is an expression with side effects, don't warn. */
2060 if (TREE_SIDE_EFFECTS (exp
))
2063 switch (TREE_CODE (exp
))
2065 case PREINCREMENT_EXPR
:
2066 case POSTINCREMENT_EXPR
:
2067 case PREDECREMENT_EXPR
:
2068 case POSTDECREMENT_EXPR
:
2073 case METHOD_CALL_EXPR
:
2075 case TRY_CATCH_EXPR
:
2076 case WITH_CLEANUP_EXPR
:
2081 /* For a binding, warn if no side effect within it. */
2082 return warn_if_unused_value (TREE_OPERAND (exp
, 1));
2085 return warn_if_unused_value (TREE_OPERAND (exp
, 1));
2087 case TRUTH_ORIF_EXPR
:
2088 case TRUTH_ANDIF_EXPR
:
2089 /* In && or ||, warn if 2nd operand has no side effect. */
2090 return warn_if_unused_value (TREE_OPERAND (exp
, 1));
2093 if (TREE_NO_UNUSED_WARNING (exp
))
2095 if (warn_if_unused_value (TREE_OPERAND (exp
, 0)))
2097 /* Let people do `(foo (), 0)' without a warning. */
2098 if (TREE_CONSTANT (TREE_OPERAND (exp
, 1)))
2100 return warn_if_unused_value (TREE_OPERAND (exp
, 1));
2104 case NON_LVALUE_EXPR
:
2105 /* Don't warn about conversions not explicit in the user's program. */
2106 if (TREE_NO_UNUSED_WARNING (exp
))
2108 /* Assignment to a cast usually results in a cast of a modify.
2109 Don't complain about that. There can be an arbitrary number of
2110 casts before the modify, so we must loop until we find the first
2111 non-cast expression and then test to see if that is a modify. */
2113 tree tem
= TREE_OPERAND (exp
, 0);
2115 while (TREE_CODE (tem
) == CONVERT_EXPR
|| TREE_CODE (tem
) == NOP_EXPR
)
2116 tem
= TREE_OPERAND (tem
, 0);
2118 if (TREE_CODE (tem
) == MODIFY_EXPR
|| TREE_CODE (tem
) == INIT_EXPR
2119 || TREE_CODE (tem
) == CALL_EXPR
)
2125 /* Don't warn about automatic dereferencing of references, since
2126 the user cannot control it. */
2127 if (TREE_CODE (TREE_TYPE (TREE_OPERAND (exp
, 0))) == REFERENCE_TYPE
)
2128 return warn_if_unused_value (TREE_OPERAND (exp
, 0));
2132 /* Referencing a volatile value is a side effect, so don't warn. */
2134 || TREE_CODE_CLASS (TREE_CODE (exp
)) == 'r')
2135 && TREE_THIS_VOLATILE (exp
))
2138 /* If this is an expression which has no operands, there is no value
2139 to be unused. There are no such language-independent codes,
2140 but front ends may define such. */
2141 if (TREE_CODE_CLASS (TREE_CODE (exp
)) == 'e'
2142 && TREE_CODE_LENGTH (TREE_CODE (exp
)) == 0)
2146 warning_with_file_and_line (emit_filename
, emit_lineno
,
2147 "value computed is not used");
2152 /* Clear out the memory of the last expression evaluated. */
2160 /* Begin a statement which will return a value.
2161 Return the RTL_EXPR for this statement expr.
2162 The caller must save that value and pass it to expand_end_stmt_expr. */
2165 expand_start_stmt_expr ()
2169 /* Make the RTL_EXPR node temporary, not momentary,
2170 so that rtl_expr_chain doesn't become garbage. */
2171 t
= make_node (RTL_EXPR
);
2172 do_pending_stack_adjust ();
2173 start_sequence_for_rtl_expr (t
);
2175 expr_stmts_for_value
++;
2179 /* Restore the previous state at the end of a statement that returns a value.
2180 Returns a tree node representing the statement's value and the
2181 insns to compute the value.
2183 The nodes of that expression have been freed by now, so we cannot use them.
2184 But we don't want to do that anyway; the expression has already been
2185 evaluated and now we just want to use the value. So generate a RTL_EXPR
2186 with the proper type and RTL value.
2188 If the last substatement was not an expression,
2189 return something with type `void'. */
2192 expand_end_stmt_expr (t
)
2197 if (last_expr_type
== 0)
2199 last_expr_type
= void_type_node
;
2200 last_expr_value
= const0_rtx
;
2202 else if (last_expr_value
== 0)
2203 /* There are some cases where this can happen, such as when the
2204 statement is void type. */
2205 last_expr_value
= const0_rtx
;
2206 else if (GET_CODE (last_expr_value
) != REG
&& ! CONSTANT_P (last_expr_value
))
2207 /* Remove any possible QUEUED. */
2208 last_expr_value
= protect_from_queue (last_expr_value
, 0);
2212 TREE_TYPE (t
) = last_expr_type
;
2213 RTL_EXPR_RTL (t
) = last_expr_value
;
2214 RTL_EXPR_SEQUENCE (t
) = get_insns ();
2216 rtl_expr_chain
= tree_cons (NULL_TREE
, t
, rtl_expr_chain
);
2220 /* Don't consider deleting this expr or containing exprs at tree level. */
2221 TREE_SIDE_EFFECTS (t
) = 1;
2222 /* Propagate volatility of the actual RTL expr. */
2223 TREE_THIS_VOLATILE (t
) = volatile_refs_p (last_expr_value
);
2226 expr_stmts_for_value
--;
2231 /* Generate RTL for the start of an if-then. COND is the expression
2232 whose truth should be tested.
2234 If EXITFLAG is nonzero, this conditional is visible to
2235 `exit_something'. */
2238 expand_start_cond (cond
, exitflag
)
2242 struct nesting
*thiscond
= ALLOC_NESTING ();
2244 /* Make an entry on cond_stack for the cond we are entering. */
2246 thiscond
->next
= cond_stack
;
2247 thiscond
->all
= nesting_stack
;
2248 thiscond
->depth
= ++nesting_depth
;
2249 thiscond
->data
.cond
.next_label
= gen_label_rtx ();
2250 /* Before we encounter an `else', we don't need a separate exit label
2251 unless there are supposed to be exit statements
2252 to exit this conditional. */
2253 thiscond
->exit_label
= exitflag
? gen_label_rtx () : 0;
2254 thiscond
->data
.cond
.endif_label
= thiscond
->exit_label
;
2255 cond_stack
= thiscond
;
2256 nesting_stack
= thiscond
;
2258 do_jump (cond
, thiscond
->data
.cond
.next_label
, NULL_RTX
);
2261 /* Generate RTL between then-clause and the elseif-clause
2262 of an if-then-elseif-.... */
2265 expand_start_elseif (cond
)
2268 if (cond_stack
->data
.cond
.endif_label
== 0)
2269 cond_stack
->data
.cond
.endif_label
= gen_label_rtx ();
2270 emit_jump (cond_stack
->data
.cond
.endif_label
);
2271 emit_label (cond_stack
->data
.cond
.next_label
);
2272 cond_stack
->data
.cond
.next_label
= gen_label_rtx ();
2273 do_jump (cond
, cond_stack
->data
.cond
.next_label
, NULL_RTX
);
2276 /* Generate RTL between the then-clause and the else-clause
2277 of an if-then-else. */
2280 expand_start_else ()
2282 if (cond_stack
->data
.cond
.endif_label
== 0)
2283 cond_stack
->data
.cond
.endif_label
= gen_label_rtx ();
2285 emit_jump (cond_stack
->data
.cond
.endif_label
);
2286 emit_label (cond_stack
->data
.cond
.next_label
);
2287 cond_stack
->data
.cond
.next_label
= 0; /* No more _else or _elseif calls. */
2290 /* After calling expand_start_else, turn this "else" into an "else if"
2291 by providing another condition. */
2294 expand_elseif (cond
)
2297 cond_stack
->data
.cond
.next_label
= gen_label_rtx ();
2298 do_jump (cond
, cond_stack
->data
.cond
.next_label
, NULL_RTX
);
2301 /* Generate RTL for the end of an if-then.
2302 Pop the record for it off of cond_stack. */
2307 struct nesting
*thiscond
= cond_stack
;
2309 do_pending_stack_adjust ();
2310 if (thiscond
->data
.cond
.next_label
)
2311 emit_label (thiscond
->data
.cond
.next_label
);
2312 if (thiscond
->data
.cond
.endif_label
)
2313 emit_label (thiscond
->data
.cond
.endif_label
);
2315 POPSTACK (cond_stack
);
2319 /* Generate RTL for the start of a loop. EXIT_FLAG is nonzero if this
2320 loop should be exited by `exit_something'. This is a loop for which
2321 `expand_continue' will jump to the top of the loop.
2323 Make an entry on loop_stack to record the labels associated with
2327 expand_start_loop (exit_flag
)
2330 register struct nesting
*thisloop
= ALLOC_NESTING ();
2332 /* Make an entry on loop_stack for the loop we are entering. */
2334 thisloop
->next
= loop_stack
;
2335 thisloop
->all
= nesting_stack
;
2336 thisloop
->depth
= ++nesting_depth
;
2337 thisloop
->data
.loop
.start_label
= gen_label_rtx ();
2338 thisloop
->data
.loop
.end_label
= gen_label_rtx ();
2339 thisloop
->data
.loop
.alt_end_label
= 0;
2340 thisloop
->data
.loop
.continue_label
= thisloop
->data
.loop
.start_label
;
2341 thisloop
->exit_label
= exit_flag
? thisloop
->data
.loop
.end_label
: 0;
2342 loop_stack
= thisloop
;
2343 nesting_stack
= thisloop
;
2345 do_pending_stack_adjust ();
2347 emit_note (NULL
, NOTE_INSN_LOOP_BEG
);
2348 emit_label (thisloop
->data
.loop
.start_label
);
2353 /* Like expand_start_loop but for a loop where the continuation point
2354 (for expand_continue_loop) will be specified explicitly. */
2357 expand_start_loop_continue_elsewhere (exit_flag
)
2360 struct nesting
*thisloop
= expand_start_loop (exit_flag
);
2361 loop_stack
->data
.loop
.continue_label
= gen_label_rtx ();
2365 /* Begin a null, aka do { } while (0) "loop". But since the contents
2366 of said loop can still contain a break, we must frob the loop nest. */
2369 expand_start_null_loop ()
2371 register struct nesting
*thisloop
= ALLOC_NESTING ();
2373 /* Make an entry on loop_stack for the loop we are entering. */
2375 thisloop
->next
= loop_stack
;
2376 thisloop
->all
= nesting_stack
;
2377 thisloop
->depth
= ++nesting_depth
;
2378 thisloop
->data
.loop
.start_label
= emit_note (NULL
, NOTE_INSN_DELETED
);
2379 thisloop
->data
.loop
.end_label
= gen_label_rtx ();
2380 thisloop
->data
.loop
.alt_end_label
= NULL_RTX
;
2381 thisloop
->data
.loop
.continue_label
= thisloop
->data
.loop
.end_label
;
2382 thisloop
->exit_label
= thisloop
->data
.loop
.end_label
;
2383 loop_stack
= thisloop
;
2384 nesting_stack
= thisloop
;
2389 /* Specify the continuation point for a loop started with
2390 expand_start_loop_continue_elsewhere.
2391 Use this at the point in the code to which a continue statement
2395 expand_loop_continue_here ()
2397 do_pending_stack_adjust ();
2398 emit_note (NULL
, NOTE_INSN_LOOP_CONT
);
2399 emit_label (loop_stack
->data
.loop
.continue_label
);
2402 /* Finish a loop. Generate a jump back to the top and the loop-exit label.
2403 Pop the block off of loop_stack. */
2408 rtx start_label
= loop_stack
->data
.loop
.start_label
;
2409 rtx insn
= get_last_insn ();
2410 int needs_end_jump
= 1;
2412 /* Mark the continue-point at the top of the loop if none elsewhere. */
2413 if (start_label
== loop_stack
->data
.loop
.continue_label
)
2414 emit_note_before (NOTE_INSN_LOOP_CONT
, start_label
);
2416 do_pending_stack_adjust ();
2418 /* If optimizing, perhaps reorder the loop.
2419 First, try to use a condjump near the end.
2420 expand_exit_loop_if_false ends loops with unconditional jumps,
2423 if (test) goto label;
2425 goto loop_stack->data.loop.end_label
2429 If we find such a pattern, we can end the loop earlier. */
2432 && GET_CODE (insn
) == CODE_LABEL
2433 && LABEL_NAME (insn
) == NULL
2434 && GET_CODE (PREV_INSN (insn
)) == BARRIER
)
2437 rtx jump
= PREV_INSN (PREV_INSN (label
));
2439 if (GET_CODE (jump
) == JUMP_INSN
2440 && GET_CODE (PATTERN (jump
)) == SET
2441 && SET_DEST (PATTERN (jump
)) == pc_rtx
2442 && GET_CODE (SET_SRC (PATTERN (jump
))) == LABEL_REF
2443 && (XEXP (SET_SRC (PATTERN (jump
)), 0)
2444 == loop_stack
->data
.loop
.end_label
))
2448 /* The test might be complex and reference LABEL multiple times,
2449 like the loop in loop_iterations to set vtop. To handle this,
2451 insn
= PREV_INSN (label
);
2452 reorder_insns (label
, label
, start_label
);
2454 for (prev
= PREV_INSN (jump
);; prev
= PREV_INSN (prev
))
2456 /* We ignore line number notes, but if we see any other note,
2457 in particular NOTE_INSN_BLOCK_*, NOTE_INSN_EH_REGION_*,
2458 NOTE_INSN_LOOP_*, we disable this optimization. */
2459 if (GET_CODE (prev
) == NOTE
)
2461 if (NOTE_LINE_NUMBER (prev
) < 0)
2465 if (GET_CODE (prev
) == CODE_LABEL
)
2467 if (GET_CODE (prev
) == JUMP_INSN
)
2469 if (GET_CODE (PATTERN (prev
)) == SET
2470 && SET_DEST (PATTERN (prev
)) == pc_rtx
2471 && GET_CODE (SET_SRC (PATTERN (prev
))) == IF_THEN_ELSE
2472 && (GET_CODE (XEXP (SET_SRC (PATTERN (prev
)), 1))
2474 && XEXP (XEXP (SET_SRC (PATTERN (prev
)), 1), 0) == label
)
2476 XEXP (XEXP (SET_SRC (PATTERN (prev
)), 1), 0)
2478 emit_note_after (NOTE_INSN_LOOP_END
, prev
);
2487 /* If the loop starts with a loop exit, roll that to the end where
2488 it will optimize together with the jump back.
2490 We look for the conditional branch to the exit, except that once
2491 we find such a branch, we don't look past 30 instructions.
2493 In more detail, if the loop presently looks like this (in pseudo-C):
2496 if (test) goto end_label;
2501 transform it to look like:
2507 if (test) goto end_label;
2508 goto newstart_label;
2511 Here, the `test' may actually consist of some reasonably complex
2512 code, terminating in a test. */
2517 ! (GET_CODE (insn
) == JUMP_INSN
2518 && GET_CODE (PATTERN (insn
)) == SET
2519 && SET_DEST (PATTERN (insn
)) == pc_rtx
2520 && GET_CODE (SET_SRC (PATTERN (insn
))) == IF_THEN_ELSE
))
2524 rtx last_test_insn
= NULL_RTX
;
2526 /* Scan insns from the top of the loop looking for a qualified
2527 conditional exit. */
2528 for (insn
= NEXT_INSN (loop_stack
->data
.loop
.start_label
); insn
;
2529 insn
= NEXT_INSN (insn
))
2531 if (GET_CODE (insn
) == NOTE
)
2534 && (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_BLOCK_BEG
2535 || NOTE_LINE_NUMBER (insn
) == NOTE_INSN_BLOCK_END
))
2536 /* The code that actually moves the exit test will
2537 carefully leave BLOCK notes in their original
2538 location. That means, however, that we can't debug
2539 the exit test itself. So, we refuse to move code
2540 containing BLOCK notes at low optimization levels. */
2543 if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_EH_REGION_BEG
)
2545 else if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_EH_REGION_END
)
2549 /* We've come to the end of an EH region, but
2550 never saw the beginning of that region. That
2551 means that an EH region begins before the top
2552 of the loop, and ends in the middle of it. The
2553 existence of such a situation violates a basic
2554 assumption in this code, since that would imply
2555 that even when EH_REGIONS is zero, we might
2556 move code out of an exception region. */
2560 /* We must not walk into a nested loop. */
2561 if (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_LOOP_BEG
)
2564 /* We already know this INSN is a NOTE, so there's no
2565 point in looking at it to see if it's a JUMP. */
2569 if (GET_CODE (insn
) == JUMP_INSN
|| GET_CODE (insn
) == INSN
)
2572 if (last_test_insn
&& num_insns
> 30)
2576 /* We don't want to move a partial EH region. Consider:
2590 This isn't legal C++, but here's what it's supposed to
2591 mean: if cond() is true, stop looping. Otherwise,
2592 call bar, and keep looping. In addition, if cond
2593 throws an exception, catch it and keep looping. Such
2594 constructs are certainy legal in LISP.
2596 We should not move the `if (cond()) 0' test since then
2597 the EH-region for the try-block would be broken up.
2598 (In this case we would the EH_BEG note for the `try'
2599 and `if cond()' but not the call to bar() or the
2602 So we don't look for tests within an EH region. */
2605 if (GET_CODE (insn
) == JUMP_INSN
2606 && GET_CODE (PATTERN (insn
)) == SET
2607 && SET_DEST (PATTERN (insn
)) == pc_rtx
)
2609 /* This is indeed a jump. */
2610 rtx dest1
= NULL_RTX
;
2611 rtx dest2
= NULL_RTX
;
2612 rtx potential_last_test
;
2613 if (GET_CODE (SET_SRC (PATTERN (insn
))) == IF_THEN_ELSE
)
2615 /* A conditional jump. */
2616 dest1
= XEXP (SET_SRC (PATTERN (insn
)), 1);
2617 dest2
= XEXP (SET_SRC (PATTERN (insn
)), 2);
2618 potential_last_test
= insn
;
2622 /* An unconditional jump. */
2623 dest1
= SET_SRC (PATTERN (insn
));
2624 /* Include the BARRIER after the JUMP. */
2625 potential_last_test
= NEXT_INSN (insn
);
2629 if (dest1
&& GET_CODE (dest1
) == LABEL_REF
2630 && ((XEXP (dest1
, 0)
2631 == loop_stack
->data
.loop
.alt_end_label
)
2633 == loop_stack
->data
.loop
.end_label
)))
2635 last_test_insn
= potential_last_test
;
2639 /* If this was a conditional jump, there may be
2640 another label at which we should look. */
2647 if (last_test_insn
!= 0 && last_test_insn
!= get_last_insn ())
2649 /* We found one. Move everything from there up
2650 to the end of the loop, and add a jump into the loop
2651 to jump to there. */
2652 register rtx newstart_label
= gen_label_rtx ();
2653 register rtx start_move
= start_label
;
2656 /* If the start label is preceded by a NOTE_INSN_LOOP_CONT note,
2657 then we want to move this note also. */
2658 if (GET_CODE (PREV_INSN (start_move
)) == NOTE
2659 && (NOTE_LINE_NUMBER (PREV_INSN (start_move
))
2660 == NOTE_INSN_LOOP_CONT
))
2661 start_move
= PREV_INSN (start_move
);
2663 emit_label_after (newstart_label
, PREV_INSN (start_move
));
2665 /* Actually move the insns. Start at the beginning, and
2666 keep copying insns until we've copied the
2668 for (insn
= start_move
; insn
; insn
= next_insn
)
2670 /* Figure out which insn comes after this one. We have
2671 to do this before we move INSN. */
2672 if (insn
== last_test_insn
)
2673 /* We've moved all the insns. */
2674 next_insn
= NULL_RTX
;
2676 next_insn
= NEXT_INSN (insn
);
2678 if (GET_CODE (insn
) == NOTE
2679 && (NOTE_LINE_NUMBER (insn
) == NOTE_INSN_BLOCK_BEG
2680 || NOTE_LINE_NUMBER (insn
) == NOTE_INSN_BLOCK_END
))
2681 /* We don't want to move NOTE_INSN_BLOCK_BEGs or
2682 NOTE_INSN_BLOCK_ENDs because the correct generation
2683 of debugging information depends on these appearing
2684 in the same order in the RTL and in the tree
2685 structure, where they are represented as BLOCKs.
2686 So, we don't move block notes. Of course, moving
2687 the code inside the block is likely to make it
2688 impossible to debug the instructions in the exit
2689 test, but such is the price of optimization. */
2692 /* Move the INSN. */
2693 reorder_insns (insn
, insn
, get_last_insn ());
2696 emit_jump_insn_after (gen_jump (start_label
),
2697 PREV_INSN (newstart_label
));
2698 emit_barrier_after (PREV_INSN (newstart_label
));
2699 start_label
= newstart_label
;
2705 emit_jump (start_label
);
2706 emit_note (NULL
, NOTE_INSN_LOOP_END
);
2708 emit_label (loop_stack
->data
.loop
.end_label
);
2710 POPSTACK (loop_stack
);
2715 /* Finish a null loop, aka do { } while (0). */
2718 expand_end_null_loop ()
2720 do_pending_stack_adjust ();
2721 emit_label (loop_stack
->data
.loop
.end_label
);
2723 POPSTACK (loop_stack
);
2728 /* Generate a jump to the current loop's continue-point.
2729 This is usually the top of the loop, but may be specified
2730 explicitly elsewhere. If not currently inside a loop,
2731 return 0 and do nothing; caller will print an error message. */
2734 expand_continue_loop (whichloop
)
2735 struct nesting
*whichloop
;
2739 whichloop
= loop_stack
;
2742 expand_goto_internal (NULL_TREE
, whichloop
->data
.loop
.continue_label
,
2747 /* Generate a jump to exit the current loop. If not currently inside a loop,
2748 return 0 and do nothing; caller will print an error message. */
2751 expand_exit_loop (whichloop
)
2752 struct nesting
*whichloop
;
2756 whichloop
= loop_stack
;
2759 expand_goto_internal (NULL_TREE
, whichloop
->data
.loop
.end_label
, NULL_RTX
);
2763 /* Generate a conditional jump to exit the current loop if COND
2764 evaluates to zero. If not currently inside a loop,
2765 return 0 and do nothing; caller will print an error message. */
2768 expand_exit_loop_if_false (whichloop
, cond
)
2769 struct nesting
*whichloop
;
2772 rtx label
= gen_label_rtx ();
2777 whichloop
= loop_stack
;
2780 /* In order to handle fixups, we actually create a conditional jump
2781 around a unconditional branch to exit the loop. If fixups are
2782 necessary, they go before the unconditional branch. */
2784 do_jump (cond
, NULL_RTX
, label
);
2785 last_insn
= get_last_insn ();
2786 if (GET_CODE (last_insn
) == CODE_LABEL
)
2787 whichloop
->data
.loop
.alt_end_label
= last_insn
;
2788 expand_goto_internal (NULL_TREE
, whichloop
->data
.loop
.end_label
,
2795 /* Return nonzero if the loop nest is empty. Else return zero. */
2798 stmt_loop_nest_empty ()
2800 /* cfun->stmt can be NULL if we are building a call to get the
2801 EH context for a setjmp/longjmp EH target and the current
2802 function was a deferred inline function. */
2803 return (cfun
->stmt
== NULL
|| loop_stack
== NULL
);
2806 /* Return non-zero if we should preserve sub-expressions as separate
2807 pseudos. We never do so if we aren't optimizing. We always do so
2808 if -fexpensive-optimizations.
2810 Otherwise, we only do so if we are in the "early" part of a loop. I.e.,
2811 the loop may still be a small one. */
2814 preserve_subexpressions_p ()
2818 if (flag_expensive_optimizations
)
2821 if (optimize
== 0 || cfun
== 0 || cfun
->stmt
== 0 || loop_stack
== 0)
2824 insn
= get_last_insn_anywhere ();
2827 && (INSN_UID (insn
) - INSN_UID (loop_stack
->data
.loop
.start_label
)
2828 < n_non_fixed_regs
* 3));
2832 /* Generate a jump to exit the current loop, conditional, binding contour
2833 or case statement. Not all such constructs are visible to this function,
2834 only those started with EXIT_FLAG nonzero. Individual languages use
2835 the EXIT_FLAG parameter to control which kinds of constructs you can
2838 If not currently inside anything that can be exited,
2839 return 0 and do nothing; caller will print an error message. */
2842 expand_exit_something ()
2846 for (n
= nesting_stack
; n
; n
= n
->all
)
2847 if (n
->exit_label
!= 0)
2849 expand_goto_internal (NULL_TREE
, n
->exit_label
, NULL_RTX
);
2856 /* Generate RTL to return from the current function, with no value.
2857 (That is, we do not do anything about returning any value.) */
2860 expand_null_return ()
2862 struct nesting
*block
= block_stack
;
2863 rtx last_insn
= get_last_insn ();
2865 /* If this function was declared to return a value, but we
2866 didn't, clobber the return registers so that they are not
2867 propogated live to the rest of the function. */
2868 clobber_return_register ();
2870 /* Does any pending block have cleanups? */
2871 while (block
&& block
->data
.block
.cleanups
== 0)
2872 block
= block
->next
;
2874 /* If yes, use a goto to return, since that runs cleanups. */
2876 expand_null_return_1 (last_insn
, block
!= 0);
2879 /* Generate RTL to return from the current function, with value VAL. */
2882 expand_value_return (val
)
2885 struct nesting
*block
= block_stack
;
2886 rtx last_insn
= get_last_insn ();
2887 rtx return_reg
= DECL_RTL (DECL_RESULT (current_function_decl
));
2889 /* Copy the value to the return location
2890 unless it's already there. */
2892 if (return_reg
!= val
)
2894 tree type
= TREE_TYPE (DECL_RESULT (current_function_decl
));
2895 #ifdef PROMOTE_FUNCTION_RETURN
2896 int unsignedp
= TREE_UNSIGNED (type
);
2897 enum machine_mode old_mode
2898 = DECL_MODE (DECL_RESULT (current_function_decl
));
2899 enum machine_mode mode
2900 = promote_mode (type
, old_mode
, &unsignedp
, 1);
2902 if (mode
!= old_mode
)
2903 val
= convert_modes (mode
, old_mode
, val
, unsignedp
);
2905 if (GET_CODE (return_reg
) == PARALLEL
)
2906 emit_group_load (return_reg
, val
, int_size_in_bytes (type
),
2909 emit_move_insn (return_reg
, val
);
2912 /* Does any pending block have cleanups? */
2914 while (block
&& block
->data
.block
.cleanups
== 0)
2915 block
= block
->next
;
2917 /* If yes, use a goto to return, since that runs cleanups.
2918 Use LAST_INSN to put cleanups *before* the move insn emitted above. */
2920 expand_null_return_1 (last_insn
, block
!= 0);
2923 /* Output a return with no value. If LAST_INSN is nonzero,
2924 pretend that the return takes place after LAST_INSN.
2925 If USE_GOTO is nonzero then don't use a return instruction;
2926 go to the return label instead. This causes any cleanups
2927 of pending blocks to be executed normally. */
2930 expand_null_return_1 (last_insn
, use_goto
)
2934 rtx end_label
= cleanup_label
? cleanup_label
: return_label
;
2936 clear_pending_stack_adjust ();
2937 do_pending_stack_adjust ();
2940 /* PCC-struct return always uses an epilogue. */
2941 if (current_function_returns_pcc_struct
|| use_goto
)
2944 end_label
= return_label
= gen_label_rtx ();
2945 expand_goto_internal (NULL_TREE
, end_label
, last_insn
);
2949 /* Otherwise output a simple return-insn if one is available,
2950 unless it won't do the job. */
2952 if (HAVE_return
&& use_goto
== 0 && cleanup_label
== 0)
2954 emit_jump_insn (gen_return ());
2960 /* Otherwise jump to the epilogue. */
2961 expand_goto_internal (NULL_TREE
, end_label
, last_insn
);
2964 /* Generate RTL to evaluate the expression RETVAL and return it
2965 from the current function. */
2968 expand_return (retval
)
2971 /* If there are any cleanups to be performed, then they will
2972 be inserted following LAST_INSN. It is desirable
2973 that the last_insn, for such purposes, should be the
2974 last insn before computing the return value. Otherwise, cleanups
2975 which call functions can clobber the return value. */
2976 /* ??? rms: I think that is erroneous, because in C++ it would
2977 run destructors on variables that might be used in the subsequent
2978 computation of the return value. */
2981 register rtx val
= 0;
2984 /* If function wants no value, give it none. */
2985 if (TREE_CODE (TREE_TYPE (TREE_TYPE (current_function_decl
))) == VOID_TYPE
)
2987 expand_expr (retval
, NULL_RTX
, VOIDmode
, 0);
2989 expand_null_return ();
2993 if (retval
== error_mark_node
)
2995 /* Treat this like a return of no value from a function that
2997 expand_null_return ();
3000 else if (TREE_CODE (retval
) == RESULT_DECL
)
3001 retval_rhs
= retval
;
3002 else if ((TREE_CODE (retval
) == MODIFY_EXPR
|| TREE_CODE (retval
) == INIT_EXPR
)
3003 && TREE_CODE (TREE_OPERAND (retval
, 0)) == RESULT_DECL
)
3004 retval_rhs
= TREE_OPERAND (retval
, 1);
3005 else if (VOID_TYPE_P (TREE_TYPE (retval
)))
3006 /* Recognize tail-recursive call to void function. */
3007 retval_rhs
= retval
;
3009 retval_rhs
= NULL_TREE
;
3011 last_insn
= get_last_insn ();
3013 /* Distribute return down conditional expr if either of the sides
3014 may involve tail recursion (see test below). This enhances the number
3015 of tail recursions we see. Don't do this always since it can produce
3016 sub-optimal code in some cases and we distribute assignments into
3017 conditional expressions when it would help. */
3019 if (optimize
&& retval_rhs
!= 0
3020 && frame_offset
== 0
3021 && TREE_CODE (retval_rhs
) == COND_EXPR
3022 && (TREE_CODE (TREE_OPERAND (retval_rhs
, 1)) == CALL_EXPR
3023 || TREE_CODE (TREE_OPERAND (retval_rhs
, 2)) == CALL_EXPR
))
3025 rtx label
= gen_label_rtx ();
3028 do_jump (TREE_OPERAND (retval_rhs
, 0), label
, NULL_RTX
);
3029 start_cleanup_deferral ();
3030 expr
= build (MODIFY_EXPR
, TREE_TYPE (TREE_TYPE (current_function_decl
)),
3031 DECL_RESULT (current_function_decl
),
3032 TREE_OPERAND (retval_rhs
, 1));
3033 TREE_SIDE_EFFECTS (expr
) = 1;
3034 expand_return (expr
);
3037 expr
= build (MODIFY_EXPR
, TREE_TYPE (TREE_TYPE (current_function_decl
)),
3038 DECL_RESULT (current_function_decl
),
3039 TREE_OPERAND (retval_rhs
, 2));
3040 TREE_SIDE_EFFECTS (expr
) = 1;
3041 expand_return (expr
);
3042 end_cleanup_deferral ();
3046 result_rtl
= DECL_RTL (DECL_RESULT (current_function_decl
));
3048 /* If the result is an aggregate that is being returned in one (or more)
3049 registers, load the registers here. The compiler currently can't handle
3050 copying a BLKmode value into registers. We could put this code in a
3051 more general area (for use by everyone instead of just function
3052 call/return), but until this feature is generally usable it is kept here
3053 (and in expand_call). The value must go into a pseudo in case there
3054 are cleanups that will clobber the real return register. */
3057 && TYPE_MODE (TREE_TYPE (retval_rhs
)) == BLKmode
3058 && GET_CODE (result_rtl
) == REG
)
3061 unsigned HOST_WIDE_INT bitpos
, xbitpos
;
3062 unsigned HOST_WIDE_INT big_endian_correction
= 0;
3063 unsigned HOST_WIDE_INT bytes
3064 = int_size_in_bytes (TREE_TYPE (retval_rhs
));
3065 int n_regs
= (bytes
+ UNITS_PER_WORD
- 1) / UNITS_PER_WORD
;
3066 unsigned int bitsize
3067 = MIN (TYPE_ALIGN (TREE_TYPE (retval_rhs
)), BITS_PER_WORD
);
3068 rtx
*result_pseudos
= (rtx
*) alloca (sizeof (rtx
) * n_regs
);
3069 rtx result_reg
, src
= NULL_RTX
, dst
= NULL_RTX
;
3070 rtx result_val
= expand_expr (retval_rhs
, NULL_RTX
, VOIDmode
, 0);
3071 enum machine_mode tmpmode
, result_reg_mode
;
3075 expand_null_return ();
3079 /* Structures whose size is not a multiple of a word are aligned
3080 to the least significant byte (to the right). On a BYTES_BIG_ENDIAN
3081 machine, this means we must skip the empty high order bytes when
3082 calculating the bit offset. */
3083 if (BYTES_BIG_ENDIAN
&& bytes
% UNITS_PER_WORD
)
3084 big_endian_correction
= (BITS_PER_WORD
- ((bytes
% UNITS_PER_WORD
)
3087 /* Copy the structure BITSIZE bits at a time. */
3088 for (bitpos
= 0, xbitpos
= big_endian_correction
;
3089 bitpos
< bytes
* BITS_PER_UNIT
;
3090 bitpos
+= bitsize
, xbitpos
+= bitsize
)
3092 /* We need a new destination pseudo each time xbitpos is
3093 on a word boundary and when xbitpos == big_endian_correction
3094 (the first time through). */
3095 if (xbitpos
% BITS_PER_WORD
== 0
3096 || xbitpos
== big_endian_correction
)
3098 /* Generate an appropriate register. */
3099 dst
= gen_reg_rtx (word_mode
);
3100 result_pseudos
[xbitpos
/ BITS_PER_WORD
] = dst
;
3102 /* Clobber the destination before we move anything into it. */
3103 emit_insn (gen_rtx_CLOBBER (VOIDmode
, dst
));
3106 /* We need a new source operand each time bitpos is on a word
3108 if (bitpos
% BITS_PER_WORD
== 0)
3109 src
= operand_subword_force (result_val
,
3110 bitpos
/ BITS_PER_WORD
,
3113 /* Use bitpos for the source extraction (left justified) and
3114 xbitpos for the destination store (right justified). */
3115 store_bit_field (dst
, bitsize
, xbitpos
% BITS_PER_WORD
, word_mode
,
3116 extract_bit_field (src
, bitsize
,
3117 bitpos
% BITS_PER_WORD
, 1,
3118 NULL_RTX
, word_mode
, word_mode
,
3119 bitsize
, BITS_PER_WORD
),
3120 bitsize
, BITS_PER_WORD
);
3123 /* Find the smallest integer mode large enough to hold the
3124 entire structure and use that mode instead of BLKmode
3125 on the USE insn for the return register. */
3126 for (tmpmode
= GET_CLASS_NARROWEST_MODE (MODE_INT
);
3127 tmpmode
!= VOIDmode
;
3128 tmpmode
= GET_MODE_WIDER_MODE (tmpmode
))
3129 /* Have we found a large enough mode? */
3130 if (GET_MODE_SIZE (tmpmode
) >= bytes
)
3133 /* No suitable mode found. */
3134 if (tmpmode
== VOIDmode
)
3137 PUT_MODE (result_rtl
, tmpmode
);
3139 if (GET_MODE_SIZE (tmpmode
) < GET_MODE_SIZE (word_mode
))
3140 result_reg_mode
= word_mode
;
3142 result_reg_mode
= tmpmode
;
3143 result_reg
= gen_reg_rtx (result_reg_mode
);
3146 for (i
= 0; i
< n_regs
; i
++)
3147 emit_move_insn (operand_subword (result_reg
, i
, 0, result_reg_mode
),
3150 if (tmpmode
!= result_reg_mode
)
3151 result_reg
= gen_lowpart (tmpmode
, result_reg
);
3153 expand_value_return (result_reg
);
3155 else if (retval_rhs
!= 0
3156 && !VOID_TYPE_P (TREE_TYPE (retval_rhs
))
3157 && (GET_CODE (result_rtl
) == REG
3158 || (GET_CODE (result_rtl
) == PARALLEL
)))
3160 /* Calculate the return value into a temporary (usually a pseudo
3162 tree ot
= TREE_TYPE (DECL_RESULT (current_function_decl
));
3163 tree nt
= build_qualified_type (ot
, TYPE_QUALS (ot
) | TYPE_QUAL_CONST
);
3165 val
= assign_temp (nt
, 0, 0, 1);
3166 val
= expand_expr (retval_rhs
, val
, GET_MODE (val
), 0);
3167 val
= force_not_mem (val
);
3169 /* Return the calculated value, doing cleanups first. */
3170 expand_value_return (val
);
3174 /* No cleanups or no hard reg used;
3175 calculate value into hard return reg. */
3176 expand_expr (retval
, const0_rtx
, VOIDmode
, 0);
3178 expand_value_return (result_rtl
);
3182 /* Return 1 if the end of the generated RTX is not a barrier.
3183 This means code already compiled can drop through. */
3186 drop_through_at_end_p ()
3188 rtx insn
= get_last_insn ();
3189 while (insn
&& GET_CODE (insn
) == NOTE
)
3190 insn
= PREV_INSN (insn
);
3191 return insn
&& GET_CODE (insn
) != BARRIER
;
3194 /* Attempt to optimize a potential tail recursion call into a goto.
3195 ARGUMENTS are the arguments to a CALL_EXPR; LAST_INSN indicates
3196 where to place the jump to the tail recursion label.
3198 Return TRUE if the call was optimized into a goto. */
3201 optimize_tail_recursion (arguments
, last_insn
)
3205 /* Finish checking validity, and if valid emit code to set the
3206 argument variables for the new call. */
3207 if (tail_recursion_args (arguments
, DECL_ARGUMENTS (current_function_decl
)))
3209 if (tail_recursion_label
== 0)
3211 tail_recursion_label
= gen_label_rtx ();
3212 emit_label_after (tail_recursion_label
,
3213 tail_recursion_reentry
);
3216 expand_goto_internal (NULL_TREE
, tail_recursion_label
, last_insn
);
3223 /* Emit code to alter this function's formal parms for a tail-recursive call.
3224 ACTUALS is a list of actual parameter expressions (chain of TREE_LISTs).
3225 FORMALS is the chain of decls of formals.
3226 Return 1 if this can be done;
3227 otherwise return 0 and do not emit any code. */
3230 tail_recursion_args (actuals
, formals
)
3231 tree actuals
, formals
;
3233 register tree a
= actuals
, f
= formals
;
3235 register rtx
*argvec
;
3237 /* Check that number and types of actuals are compatible
3238 with the formals. This is not always true in valid C code.
3239 Also check that no formal needs to be addressable
3240 and that all formals are scalars. */
3242 /* Also count the args. */
3244 for (a
= actuals
, f
= formals
, i
= 0; a
&& f
; a
= TREE_CHAIN (a
), f
= TREE_CHAIN (f
), i
++)
3246 if (TYPE_MAIN_VARIANT (TREE_TYPE (TREE_VALUE (a
)))
3247 != TYPE_MAIN_VARIANT (TREE_TYPE (f
)))
3249 if (GET_CODE (DECL_RTL (f
)) != REG
|| DECL_MODE (f
) == BLKmode
)
3252 if (a
!= 0 || f
!= 0)
3255 /* Compute all the actuals. */
3257 argvec
= (rtx
*) alloca (i
* sizeof (rtx
));
3259 for (a
= actuals
, i
= 0; a
; a
= TREE_CHAIN (a
), i
++)
3260 argvec
[i
] = expand_expr (TREE_VALUE (a
), NULL_RTX
, VOIDmode
, 0);
3262 /* Find which actual values refer to current values of previous formals.
3263 Copy each of them now, before any formal is changed. */
3265 for (a
= actuals
, i
= 0; a
; a
= TREE_CHAIN (a
), i
++)
3269 for (f
= formals
, j
= 0; j
< i
; f
= TREE_CHAIN (f
), j
++)
3270 if (reg_mentioned_p (DECL_RTL (f
), argvec
[i
]))
3276 argvec
[i
] = copy_to_reg (argvec
[i
]);
3279 /* Store the values of the actuals into the formals. */
3281 for (f
= formals
, a
= actuals
, i
= 0; f
;
3282 f
= TREE_CHAIN (f
), a
= TREE_CHAIN (a
), i
++)
3284 if (GET_MODE (DECL_RTL (f
)) == GET_MODE (argvec
[i
]))
3285 emit_move_insn (DECL_RTL (f
), argvec
[i
]);
3287 convert_move (DECL_RTL (f
), argvec
[i
],
3288 TREE_UNSIGNED (TREE_TYPE (TREE_VALUE (a
))));
3295 /* Generate the RTL code for entering a binding contour.
3296 The variables are declared one by one, by calls to `expand_decl'.
3298 FLAGS is a bitwise or of the following flags:
3300 1 - Nonzero if this construct should be visible to
3303 2 - Nonzero if this contour does not require a
3304 NOTE_INSN_BLOCK_BEG note. Virtually all calls from
3305 language-independent code should set this flag because they
3306 will not create corresponding BLOCK nodes. (There should be
3307 a one-to-one correspondence between NOTE_INSN_BLOCK_BEG notes
3308 and BLOCKs.) If this flag is set, MARK_ENDS should be zero
3309 when expand_end_bindings is called.
3311 If we are creating a NOTE_INSN_BLOCK_BEG note, a BLOCK may
3312 optionally be supplied. If so, it becomes the NOTE_BLOCK for the
3316 expand_start_bindings_and_block (flags
, block
)
3320 struct nesting
*thisblock
= ALLOC_NESTING ();
3322 int exit_flag
= ((flags
& 1) != 0);
3323 int block_flag
= ((flags
& 2) == 0);
3325 /* If a BLOCK is supplied, then the caller should be requesting a
3326 NOTE_INSN_BLOCK_BEG note. */
3327 if (!block_flag
&& block
)
3330 /* Create a note to mark the beginning of the block. */
3333 note
= emit_note (NULL
, NOTE_INSN_BLOCK_BEG
);
3334 NOTE_BLOCK (note
) = block
;
3337 note
= emit_note (NULL
, NOTE_INSN_DELETED
);
3339 /* Make an entry on block_stack for the block we are entering. */
3341 thisblock
->next
= block_stack
;
3342 thisblock
->all
= nesting_stack
;
3343 thisblock
->depth
= ++nesting_depth
;
3344 thisblock
->data
.block
.stack_level
= 0;
3345 thisblock
->data
.block
.cleanups
= 0;
3346 thisblock
->data
.block
.n_function_calls
= 0;
3347 thisblock
->data
.block
.exception_region
= 0;
3348 thisblock
->data
.block
.block_target_temp_slot_level
= target_temp_slot_level
;
3350 thisblock
->data
.block
.conditional_code
= 0;
3351 thisblock
->data
.block
.last_unconditional_cleanup
= note
;
3352 /* When we insert instructions after the last unconditional cleanup,
3353 we don't adjust last_insn. That means that a later add_insn will
3354 clobber the instructions we've just added. The easiest way to
3355 fix this is to just insert another instruction here, so that the
3356 instructions inserted after the last unconditional cleanup are
3357 never the last instruction. */
3358 emit_note (NULL
, NOTE_INSN_DELETED
);
3359 thisblock
->data
.block
.cleanup_ptr
= &thisblock
->data
.block
.cleanups
;
3362 && !(block_stack
->data
.block
.cleanups
== NULL_TREE
3363 && block_stack
->data
.block
.outer_cleanups
== NULL_TREE
))
3364 thisblock
->data
.block
.outer_cleanups
3365 = tree_cons (NULL_TREE
, block_stack
->data
.block
.cleanups
,
3366 block_stack
->data
.block
.outer_cleanups
);
3368 thisblock
->data
.block
.outer_cleanups
= 0;
3369 thisblock
->data
.block
.label_chain
= 0;
3370 thisblock
->data
.block
.innermost_stack_block
= stack_block_stack
;
3371 thisblock
->data
.block
.first_insn
= note
;
3372 thisblock
->data
.block
.block_start_count
= ++current_block_start_count
;
3373 thisblock
->exit_label
= exit_flag
? gen_label_rtx () : 0;
3374 block_stack
= thisblock
;
3375 nesting_stack
= thisblock
;
3377 /* Make a new level for allocating stack slots. */
3381 /* Specify the scope of temporaries created by TARGET_EXPRs. Similar
3382 to CLEANUP_POINT_EXPR, but handles cases when a series of calls to
3383 expand_expr are made. After we end the region, we know that all
3384 space for all temporaries that were created by TARGET_EXPRs will be
3385 destroyed and their space freed for reuse. */
3388 expand_start_target_temps ()
3390 /* This is so that even if the result is preserved, the space
3391 allocated will be freed, as we know that it is no longer in use. */
3394 /* Start a new binding layer that will keep track of all cleanup
3395 actions to be performed. */
3396 expand_start_bindings (2);
3398 target_temp_slot_level
= temp_slot_level
;
3402 expand_end_target_temps ()
3404 expand_end_bindings (NULL_TREE
, 0, 0);
3406 /* This is so that even if the result is preserved, the space
3407 allocated will be freed, as we know that it is no longer in use. */
3411 /* Given a pointer to a BLOCK node return non-zero if (and only if) the node
3412 in question represents the outermost pair of curly braces (i.e. the "body
3413 block") of a function or method.
3415 For any BLOCK node representing a "body block" of a function or method, the
3416 BLOCK_SUPERCONTEXT of the node will point to another BLOCK node which
3417 represents the outermost (function) scope for the function or method (i.e.
3418 the one which includes the formal parameters). The BLOCK_SUPERCONTEXT of
3419 *that* node in turn will point to the relevant FUNCTION_DECL node. */
3422 is_body_block (stmt
)
3425 if (TREE_CODE (stmt
) == BLOCK
)
3427 tree parent
= BLOCK_SUPERCONTEXT (stmt
);
3429 if (parent
&& TREE_CODE (parent
) == BLOCK
)
3431 tree grandparent
= BLOCK_SUPERCONTEXT (parent
);
3433 if (grandparent
&& TREE_CODE (grandparent
) == FUNCTION_DECL
)
3441 /* True if we are currently emitting insns in an area of output code
3442 that is controlled by a conditional expression. This is used by
3443 the cleanup handling code to generate conditional cleanup actions. */
3446 conditional_context ()
3448 return block_stack
&& block_stack
->data
.block
.conditional_code
;
3451 /* Return an opaque pointer to the current nesting level, so frontend code
3452 can check its own sanity. */
3455 current_nesting_level ()
3457 return cfun
? block_stack
: 0;
3460 /* Emit a handler label for a nonlocal goto handler.
3461 Also emit code to store the handler label in SLOT before BEFORE_INSN. */
3464 expand_nl_handler_label (slot
, before_insn
)
3465 rtx slot
, before_insn
;
3468 rtx handler_label
= gen_label_rtx ();
3470 /* Don't let jump_optimize delete the handler. */
3471 LABEL_PRESERVE_P (handler_label
) = 1;
3474 emit_move_insn (slot
, gen_rtx_LABEL_REF (Pmode
, handler_label
));
3475 insns
= get_insns ();
3477 emit_insns_before (insns
, before_insn
);
3479 emit_label (handler_label
);
3481 return handler_label
;
3484 /* Emit code to restore vital registers at the beginning of a nonlocal goto
3487 expand_nl_goto_receiver ()
3489 #ifdef HAVE_nonlocal_goto
3490 if (! HAVE_nonlocal_goto
)
3492 /* First adjust our frame pointer to its actual value. It was
3493 previously set to the start of the virtual area corresponding to
3494 the stacked variables when we branched here and now needs to be
3495 adjusted to the actual hardware fp value.
3497 Assignments are to virtual registers are converted by
3498 instantiate_virtual_regs into the corresponding assignment
3499 to the underlying register (fp in this case) that makes
3500 the original assignment true.
3501 So the following insn will actually be
3502 decrementing fp by STARTING_FRAME_OFFSET. */
3503 emit_move_insn (virtual_stack_vars_rtx
, hard_frame_pointer_rtx
);
3505 #if ARG_POINTER_REGNUM != HARD_FRAME_POINTER_REGNUM
3506 if (fixed_regs
[ARG_POINTER_REGNUM
])
3508 #ifdef ELIMINABLE_REGS
3509 /* If the argument pointer can be eliminated in favor of the
3510 frame pointer, we don't need to restore it. We assume here
3511 that if such an elimination is present, it can always be used.
3512 This is the case on all known machines; if we don't make this
3513 assumption, we do unnecessary saving on many machines. */
3514 static struct elims
{int from
, to
;} elim_regs
[] = ELIMINABLE_REGS
;
3517 for (i
= 0; i
< ARRAY_SIZE (elim_regs
); i
++)
3518 if (elim_regs
[i
].from
== ARG_POINTER_REGNUM
3519 && elim_regs
[i
].to
== HARD_FRAME_POINTER_REGNUM
)
3522 if (i
== ARRAY_SIZE (elim_regs
))
3525 /* Now restore our arg pointer from the address at which it
3526 was saved in our stack frame.
3527 If there hasn't be space allocated for it yet, make
3529 if (arg_pointer_save_area
== 0)
3530 arg_pointer_save_area
3531 = assign_stack_local (Pmode
, GET_MODE_SIZE (Pmode
), 0);
3532 emit_move_insn (virtual_incoming_args_rtx
,
3533 /* We need a pseudo here, or else
3534 instantiate_virtual_regs_1 complains. */
3535 copy_to_reg (arg_pointer_save_area
));
3540 #ifdef HAVE_nonlocal_goto_receiver
3541 if (HAVE_nonlocal_goto_receiver
)
3542 emit_insn (gen_nonlocal_goto_receiver ());
3546 /* Make handlers for nonlocal gotos taking place in the function calls in
3550 expand_nl_goto_receivers (thisblock
)
3551 struct nesting
*thisblock
;
3554 rtx afterward
= gen_label_rtx ();
3559 /* Record the handler address in the stack slot for that purpose,
3560 during this block, saving and restoring the outer value. */
3561 if (thisblock
->next
!= 0)
3562 for (slot
= nonlocal_goto_handler_slots
; slot
; slot
= XEXP (slot
, 1))
3564 rtx save_receiver
= gen_reg_rtx (Pmode
);
3565 emit_move_insn (XEXP (slot
, 0), save_receiver
);
3568 emit_move_insn (save_receiver
, XEXP (slot
, 0));
3569 insns
= get_insns ();
3571 emit_insns_before (insns
, thisblock
->data
.block
.first_insn
);
3574 /* Jump around the handlers; they run only when specially invoked. */
3575 emit_jump (afterward
);
3577 /* Make a separate handler for each label. */
3578 link
= nonlocal_labels
;
3579 slot
= nonlocal_goto_handler_slots
;
3580 label_list
= NULL_RTX
;
3581 for (; link
; link
= TREE_CHAIN (link
), slot
= XEXP (slot
, 1))
3582 /* Skip any labels we shouldn't be able to jump to from here,
3583 we generate one special handler for all of them below which just calls
3585 if (! DECL_TOO_LATE (TREE_VALUE (link
)))
3588 lab
= expand_nl_handler_label (XEXP (slot
, 0),
3589 thisblock
->data
.block
.first_insn
);
3590 label_list
= gen_rtx_EXPR_LIST (VOIDmode
, lab
, label_list
);
3592 expand_nl_goto_receiver ();
3594 /* Jump to the "real" nonlocal label. */
3595 expand_goto (TREE_VALUE (link
));
3598 /* A second pass over all nonlocal labels; this time we handle those
3599 we should not be able to jump to at this point. */
3600 link
= nonlocal_labels
;
3601 slot
= nonlocal_goto_handler_slots
;
3603 for (; link
; link
= TREE_CHAIN (link
), slot
= XEXP (slot
, 1))
3604 if (DECL_TOO_LATE (TREE_VALUE (link
)))
3607 lab
= expand_nl_handler_label (XEXP (slot
, 0),
3608 thisblock
->data
.block
.first_insn
);
3609 label_list
= gen_rtx_EXPR_LIST (VOIDmode
, lab
, label_list
);
3615 expand_nl_goto_receiver ();
3616 emit_library_call (gen_rtx_SYMBOL_REF (Pmode
, "abort"), 0,
3621 nonlocal_goto_handler_labels
= label_list
;
3622 emit_label (afterward
);
3625 /* Warn about any unused VARS (which may contain nodes other than
3626 VAR_DECLs, but such nodes are ignored). The nodes are connected
3627 via the TREE_CHAIN field. */
3630 warn_about_unused_variables (vars
)
3635 if (warn_unused_variable
)
3636 for (decl
= vars
; decl
; decl
= TREE_CHAIN (decl
))
3637 if (TREE_CODE (decl
) == VAR_DECL
3638 && ! TREE_USED (decl
)
3639 && ! DECL_IN_SYSTEM_HEADER (decl
)
3640 && DECL_NAME (decl
) && ! DECL_ARTIFICIAL (decl
))
3641 warning_with_decl (decl
, "unused variable `%s'");
3644 /* Generate RTL code to terminate a binding contour.
3646 VARS is the chain of VAR_DECL nodes for the variables bound in this
3647 contour. There may actually be other nodes in this chain, but any
3648 nodes other than VAR_DECLS are ignored.
3650 MARK_ENDS is nonzero if we should put a note at the beginning
3651 and end of this binding contour.
3653 DONT_JUMP_IN is nonzero if it is not valid to jump into this contour.
3654 (That is true automatically if the contour has a saved stack level.) */
3657 expand_end_bindings (vars
, mark_ends
, dont_jump_in
)
3662 register struct nesting
*thisblock
= block_stack
;
3664 /* If any of the variables in this scope were not used, warn the
3666 warn_about_unused_variables (vars
);
3668 if (thisblock
->exit_label
)
3670 do_pending_stack_adjust ();
3671 emit_label (thisblock
->exit_label
);
3674 /* If necessary, make handlers for nonlocal gotos taking
3675 place in the function calls in this block. */
3676 if (function_call_count
!= thisblock
->data
.block
.n_function_calls
3678 /* Make handler for outermost block
3679 if there were any nonlocal gotos to this function. */
3680 && (thisblock
->next
== 0 ? current_function_has_nonlocal_label
3681 /* Make handler for inner block if it has something
3682 special to do when you jump out of it. */
3683 : (thisblock
->data
.block
.cleanups
!= 0
3684 || thisblock
->data
.block
.stack_level
!= 0)))
3685 expand_nl_goto_receivers (thisblock
);
3687 /* Don't allow jumping into a block that has a stack level.
3688 Cleanups are allowed, though. */
3690 || thisblock
->data
.block
.stack_level
!= 0)
3692 struct label_chain
*chain
;
3694 /* Any labels in this block are no longer valid to go to.
3695 Mark them to cause an error message. */
3696 for (chain
= thisblock
->data
.block
.label_chain
; chain
; chain
= chain
->next
)
3698 DECL_TOO_LATE (chain
->label
) = 1;
3699 /* If any goto without a fixup came to this label,
3700 that must be an error, because gotos without fixups
3701 come from outside all saved stack-levels. */
3702 if (TREE_ADDRESSABLE (chain
->label
))
3703 error_with_decl (chain
->label
,
3704 "label `%s' used before containing binding contour");
3708 /* Restore stack level in effect before the block
3709 (only if variable-size objects allocated). */
3710 /* Perform any cleanups associated with the block. */
3712 if (thisblock
->data
.block
.stack_level
!= 0
3713 || thisblock
->data
.block
.cleanups
!= 0)
3718 /* Don't let cleanups affect ({...}) constructs. */
3719 int old_expr_stmts_for_value
= expr_stmts_for_value
;
3720 rtx old_last_expr_value
= last_expr_value
;
3721 tree old_last_expr_type
= last_expr_type
;
3722 expr_stmts_for_value
= 0;
3724 /* Only clean up here if this point can actually be reached. */
3725 insn
= get_last_insn ();
3726 if (GET_CODE (insn
) == NOTE
)
3727 insn
= prev_nonnote_insn (insn
);
3728 reachable
= (! insn
|| GET_CODE (insn
) != BARRIER
);
3730 /* Do the cleanups. */
3731 expand_cleanups (thisblock
->data
.block
.cleanups
, NULL_TREE
, 0, reachable
);
3733 do_pending_stack_adjust ();
3735 expr_stmts_for_value
= old_expr_stmts_for_value
;
3736 last_expr_value
= old_last_expr_value
;
3737 last_expr_type
= old_last_expr_type
;
3739 /* Restore the stack level. */
3741 if (reachable
&& thisblock
->data
.block
.stack_level
!= 0)
3743 emit_stack_restore (thisblock
->next
? SAVE_BLOCK
: SAVE_FUNCTION
,
3744 thisblock
->data
.block
.stack_level
, NULL_RTX
);
3745 if (nonlocal_goto_handler_slots
!= 0)
3746 emit_stack_save (SAVE_NONLOCAL
, &nonlocal_goto_stack_level
,
3750 /* Any gotos out of this block must also do these things.
3751 Also report any gotos with fixups that came to labels in this
3753 fixup_gotos (thisblock
,
3754 thisblock
->data
.block
.stack_level
,
3755 thisblock
->data
.block
.cleanups
,
3756 thisblock
->data
.block
.first_insn
,
3760 /* Mark the beginning and end of the scope if requested.
3761 We do this now, after running cleanups on the variables
3762 just going out of scope, so they are in scope for their cleanups. */
3766 rtx note
= emit_note (NULL
, NOTE_INSN_BLOCK_END
);
3767 NOTE_BLOCK (note
) = NOTE_BLOCK (thisblock
->data
.block
.first_insn
);
3770 /* Get rid of the beginning-mark if we don't make an end-mark. */
3771 NOTE_LINE_NUMBER (thisblock
->data
.block
.first_insn
) = NOTE_INSN_DELETED
;
3773 /* Restore the temporary level of TARGET_EXPRs. */
3774 target_temp_slot_level
= thisblock
->data
.block
.block_target_temp_slot_level
;
3776 /* Restore block_stack level for containing block. */
3778 stack_block_stack
= thisblock
->data
.block
.innermost_stack_block
;
3779 POPSTACK (block_stack
);
3781 /* Pop the stack slot nesting and free any slots at this level. */
3785 /* Generate code to save the stack pointer at the start of the current block
3786 and set up to restore it on exit. */
3789 save_stack_pointer ()
3791 struct nesting
*thisblock
= block_stack
;
3793 if (thisblock
->data
.block
.stack_level
== 0)
3795 emit_stack_save (thisblock
->next
? SAVE_BLOCK
: SAVE_FUNCTION
,
3796 &thisblock
->data
.block
.stack_level
,
3797 thisblock
->data
.block
.first_insn
);
3798 stack_block_stack
= thisblock
;
3802 /* Generate RTL for the automatic variable declaration DECL.
3803 (Other kinds of declarations are simply ignored if seen here.) */
3809 struct nesting
*thisblock
;
3812 type
= TREE_TYPE (decl
);
3814 /* For a CONST_DECL, set mode, alignment, and sizes from those of the
3815 type in case this node is used in a reference. */
3816 if (TREE_CODE (decl
) == CONST_DECL
)
3818 DECL_MODE (decl
) = TYPE_MODE (type
);
3819 DECL_ALIGN (decl
) = TYPE_ALIGN (type
);
3820 DECL_SIZE (decl
) = TYPE_SIZE (type
);
3821 DECL_SIZE_UNIT (decl
) = TYPE_SIZE_UNIT (type
);
3825 /* Otherwise, only automatic variables need any expansion done. Static and
3826 external variables, and external functions, will be handled by
3827 `assemble_variable' (called from finish_decl). TYPE_DECL requires
3828 nothing. PARM_DECLs are handled in `assign_parms'. */
3829 if (TREE_CODE (decl
) != VAR_DECL
)
3832 if (TREE_STATIC (decl
) || DECL_EXTERNAL (decl
))
3835 thisblock
= block_stack
;
3837 /* Create the RTL representation for the variable. */
3839 if (type
== error_mark_node
)
3840 SET_DECL_RTL (decl
, gen_rtx_MEM (BLKmode
, const0_rtx
));
3842 else if (DECL_SIZE (decl
) == 0)
3843 /* Variable with incomplete type. */
3845 if (DECL_INITIAL (decl
) == 0)
3846 /* Error message was already done; now avoid a crash. */
3847 SET_DECL_RTL (decl
, gen_rtx_MEM (BLKmode
, const0_rtx
));
3849 /* An initializer is going to decide the size of this array.
3850 Until we know the size, represent its address with a reg. */
3851 SET_DECL_RTL (decl
, gen_rtx_MEM (BLKmode
, gen_reg_rtx (Pmode
)));
3853 set_mem_attributes (DECL_RTL (decl
), decl
, 1);
3855 else if (DECL_MODE (decl
) != BLKmode
3856 /* If -ffloat-store, don't put explicit float vars
3858 && !(flag_float_store
3859 && TREE_CODE (type
) == REAL_TYPE
)
3860 && ! TREE_THIS_VOLATILE (decl
)
3861 && (DECL_REGISTER (decl
) || optimize
)
3862 /* if -fcheck-memory-usage, check all variables. */
3863 && ! current_function_check_memory_usage
)
3865 /* Automatic variable that can go in a register. */
3866 int unsignedp
= TREE_UNSIGNED (type
);
3867 enum machine_mode reg_mode
3868 = promote_mode (type
, DECL_MODE (decl
), &unsignedp
, 0);
3870 SET_DECL_RTL (decl
, gen_reg_rtx (reg_mode
));
3871 mark_user_reg (DECL_RTL (decl
));
3873 if (POINTER_TYPE_P (type
))
3874 mark_reg_pointer (DECL_RTL (decl
),
3875 TYPE_ALIGN (TREE_TYPE (TREE_TYPE (decl
))));
3877 maybe_set_unchanging (DECL_RTL (decl
), decl
);
3879 /* If something wants our address, try to use ADDRESSOF. */
3880 if (TREE_ADDRESSABLE (decl
))
3881 put_var_into_stack (decl
);
3884 else if (TREE_CODE (DECL_SIZE_UNIT (decl
)) == INTEGER_CST
3885 && ! (flag_stack_check
&& ! STACK_CHECK_BUILTIN
3886 && 0 < compare_tree_int (DECL_SIZE_UNIT (decl
),
3887 STACK_CHECK_MAX_VAR_SIZE
)))
3889 /* Variable of fixed size that goes on the stack. */
3893 /* If we previously made RTL for this decl, it must be an array
3894 whose size was determined by the initializer.
3895 The old address was a register; set that register now
3896 to the proper address. */
3897 if (DECL_RTL_SET_P (decl
))
3899 if (GET_CODE (DECL_RTL (decl
)) != MEM
3900 || GET_CODE (XEXP (DECL_RTL (decl
), 0)) != REG
)
3902 oldaddr
= XEXP (DECL_RTL (decl
), 0);
3906 assign_temp (TREE_TYPE (decl
), 1, 1, 1));
3908 /* Set alignment we actually gave this decl. */
3909 DECL_ALIGN (decl
) = (DECL_MODE (decl
) == BLKmode
? BIGGEST_ALIGNMENT
3910 : GET_MODE_BITSIZE (DECL_MODE (decl
)));
3911 DECL_USER_ALIGN (decl
) = 0;
3915 addr
= force_operand (XEXP (DECL_RTL (decl
), 0), oldaddr
);
3916 if (addr
!= oldaddr
)
3917 emit_move_insn (oldaddr
, addr
);
3921 /* Dynamic-size object: must push space on the stack. */
3925 /* Record the stack pointer on entry to block, if have
3926 not already done so. */
3927 do_pending_stack_adjust ();
3928 save_stack_pointer ();
3930 /* In function-at-a-time mode, variable_size doesn't expand this,
3932 if (TREE_CODE (type
) == ARRAY_TYPE
&& TYPE_DOMAIN (type
))
3933 expand_expr (TYPE_MAX_VALUE (TYPE_DOMAIN (type
)),
3934 const0_rtx
, VOIDmode
, 0);
3936 /* Compute the variable's size, in bytes. */
3937 size
= expand_expr (DECL_SIZE_UNIT (decl
), NULL_RTX
, VOIDmode
, 0);
3940 /* Allocate space on the stack for the variable. Note that
3941 DECL_ALIGN says how the variable is to be aligned and we
3942 cannot use it to conclude anything about the alignment of
3944 address
= allocate_dynamic_stack_space (size
, NULL_RTX
,
3945 TYPE_ALIGN (TREE_TYPE (decl
)));
3947 /* Reference the variable indirect through that rtx. */
3948 SET_DECL_RTL (decl
, gen_rtx_MEM (DECL_MODE (decl
), address
));
3950 set_mem_attributes (DECL_RTL (decl
), decl
, 1);
3952 /* Indicate the alignment we actually gave this variable. */
3953 #ifdef STACK_BOUNDARY
3954 DECL_ALIGN (decl
) = STACK_BOUNDARY
;
3956 DECL_ALIGN (decl
) = BIGGEST_ALIGNMENT
;
3958 DECL_USER_ALIGN (decl
) = 0;
3962 /* Emit code to perform the initialization of a declaration DECL. */
3965 expand_decl_init (decl
)
3968 int was_used
= TREE_USED (decl
);
3970 /* If this is a CONST_DECL, we don't have to generate any code, but
3971 if DECL_INITIAL is a constant, call expand_expr to force TREE_CST_RTL
3972 to be set while in the obstack containing the constant. If we don't
3973 do this, we can lose if we have functions nested three deep and the middle
3974 function makes a CONST_DECL whose DECL_INITIAL is a STRING_CST while
3975 the innermost function is the first to expand that STRING_CST. */
3976 if (TREE_CODE (decl
) == CONST_DECL
)
3978 if (DECL_INITIAL (decl
) && TREE_CONSTANT (DECL_INITIAL (decl
)))
3979 expand_expr (DECL_INITIAL (decl
), NULL_RTX
, VOIDmode
,
3980 EXPAND_INITIALIZER
);
3984 if (TREE_STATIC (decl
))
3987 /* Compute and store the initial value now. */
3989 if (DECL_INITIAL (decl
) == error_mark_node
)
3991 enum tree_code code
= TREE_CODE (TREE_TYPE (decl
));
3993 if (code
== INTEGER_TYPE
|| code
== REAL_TYPE
|| code
== ENUMERAL_TYPE
3994 || code
== POINTER_TYPE
|| code
== REFERENCE_TYPE
)
3995 expand_assignment (decl
, convert (TREE_TYPE (decl
), integer_zero_node
),
3999 else if (DECL_INITIAL (decl
) && TREE_CODE (DECL_INITIAL (decl
)) != TREE_LIST
)
4001 emit_line_note (DECL_SOURCE_FILE (decl
), DECL_SOURCE_LINE (decl
));
4002 expand_assignment (decl
, DECL_INITIAL (decl
), 0, 0);
4006 /* Don't let the initialization count as "using" the variable. */
4007 TREE_USED (decl
) = was_used
;
4009 /* Free any temporaries we made while initializing the decl. */
4010 preserve_temp_slots (NULL_RTX
);
4014 /* CLEANUP is an expression to be executed at exit from this binding contour;
4015 for example, in C++, it might call the destructor for this variable.
4017 We wrap CLEANUP in an UNSAVE_EXPR node, so that we can expand the
4018 CLEANUP multiple times, and have the correct semantics. This
4019 happens in exception handling, for gotos, returns, breaks that
4020 leave the current scope.
4022 If CLEANUP is nonzero and DECL is zero, we record a cleanup
4023 that is not associated with any particular variable. */
4026 expand_decl_cleanup (decl
, cleanup
)
4029 struct nesting
*thisblock
;
4031 /* Error if we are not in any block. */
4032 if (cfun
== 0 || block_stack
== 0)
4035 thisblock
= block_stack
;
4037 /* Record the cleanup if there is one. */
4043 tree
*cleanups
= &thisblock
->data
.block
.cleanups
;
4044 int cond_context
= conditional_context ();
4048 rtx flag
= gen_reg_rtx (word_mode
);
4053 emit_move_insn (flag
, const0_rtx
);
4054 set_flag_0
= get_insns ();
4057 thisblock
->data
.block
.last_unconditional_cleanup
4058 = emit_insns_after (set_flag_0
,
4059 thisblock
->data
.block
.last_unconditional_cleanup
);
4061 emit_move_insn (flag
, const1_rtx
);
4063 cond
= build_decl (VAR_DECL
, NULL_TREE
, type_for_mode (word_mode
, 1));
4064 SET_DECL_RTL (cond
, flag
);
4066 /* Conditionalize the cleanup. */
4067 cleanup
= build (COND_EXPR
, void_type_node
,
4068 truthvalue_conversion (cond
),
4069 cleanup
, integer_zero_node
);
4070 cleanup
= fold (cleanup
);
4072 cleanups
= thisblock
->data
.block
.cleanup_ptr
;
4075 cleanup
= unsave_expr (cleanup
);
4077 t
= *cleanups
= tree_cons (decl
, cleanup
, *cleanups
);
4080 /* If this block has a cleanup, it belongs in stack_block_stack. */
4081 stack_block_stack
= thisblock
;
4088 if (! using_eh_for_cleanups_p
)
4089 TREE_ADDRESSABLE (t
) = 1;
4091 expand_eh_region_start ();
4098 thisblock
->data
.block
.last_unconditional_cleanup
4099 = emit_insns_after (seq
,
4100 thisblock
->data
.block
.last_unconditional_cleanup
);
4104 thisblock
->data
.block
.last_unconditional_cleanup
4106 /* When we insert instructions after the last unconditional cleanup,
4107 we don't adjust last_insn. That means that a later add_insn will
4108 clobber the instructions we've just added. The easiest way to
4109 fix this is to just insert another instruction here, so that the
4110 instructions inserted after the last unconditional cleanup are
4111 never the last instruction. */
4112 emit_note (NULL
, NOTE_INSN_DELETED
);
4113 thisblock
->data
.block
.cleanup_ptr
= &thisblock
->data
.block
.cleanups
;
4119 /* DECL is an anonymous union. CLEANUP is a cleanup for DECL.
4120 DECL_ELTS is the list of elements that belong to DECL's type.
4121 In each, the TREE_VALUE is a VAR_DECL, and the TREE_PURPOSE a cleanup. */
4124 expand_anon_union_decl (decl
, cleanup
, decl_elts
)
4125 tree decl
, cleanup
, decl_elts
;
4127 struct nesting
*thisblock
= cfun
== 0 ? 0 : block_stack
;
4131 /* If any of the elements are addressable, so is the entire union. */
4132 for (t
= decl_elts
; t
; t
= TREE_CHAIN (t
))
4133 if (TREE_ADDRESSABLE (TREE_VALUE (t
)))
4135 TREE_ADDRESSABLE (decl
) = 1;
4140 expand_decl_cleanup (decl
, cleanup
);
4141 x
= DECL_RTL (decl
);
4143 /* Go through the elements, assigning RTL to each. */
4144 for (t
= decl_elts
; t
; t
= TREE_CHAIN (t
))
4146 tree decl_elt
= TREE_VALUE (t
);
4147 tree cleanup_elt
= TREE_PURPOSE (t
);
4148 enum machine_mode mode
= TYPE_MODE (TREE_TYPE (decl_elt
));
4150 /* Propagate the union's alignment to the elements. */
4151 DECL_ALIGN (decl_elt
) = DECL_ALIGN (decl
);
4152 DECL_USER_ALIGN (decl_elt
) = DECL_USER_ALIGN (decl
);
4154 /* If the element has BLKmode and the union doesn't, the union is
4155 aligned such that the element doesn't need to have BLKmode, so
4156 change the element's mode to the appropriate one for its size. */
4157 if (mode
== BLKmode
&& DECL_MODE (decl
) != BLKmode
)
4158 DECL_MODE (decl_elt
) = mode
4159 = mode_for_size_tree (DECL_SIZE (decl_elt
), MODE_INT
, 1);
4161 /* (SUBREG (MEM ...)) at RTL generation time is invalid, so we
4162 instead create a new MEM rtx with the proper mode. */
4163 if (GET_CODE (x
) == MEM
)
4165 if (mode
== GET_MODE (x
))
4166 SET_DECL_RTL (decl_elt
, x
);
4168 SET_DECL_RTL (decl_elt
, adjust_address_nv (x
, mode
, 0));
4170 else if (GET_CODE (x
) == REG
)
4172 if (mode
== GET_MODE (x
))
4173 SET_DECL_RTL (decl_elt
, x
);
4175 SET_DECL_RTL (decl_elt
, gen_lowpart_SUBREG (mode
, x
));
4180 /* Record the cleanup if there is one. */
4183 thisblock
->data
.block
.cleanups
4184 = tree_cons (decl_elt
, cleanup_elt
,
4185 thisblock
->data
.block
.cleanups
);
4189 /* Expand a list of cleanups LIST.
4190 Elements may be expressions or may be nested lists.
4192 If DONT_DO is nonnull, then any list-element
4193 whose TREE_PURPOSE matches DONT_DO is omitted.
4194 This is sometimes used to avoid a cleanup associated with
4195 a value that is being returned out of the scope.
4197 If IN_FIXUP is non-zero, we are generating this cleanup for a fixup
4198 goto and handle protection regions specially in that case.
4200 If REACHABLE, we emit code, otherwise just inform the exception handling
4201 code about this finalization. */
4204 expand_cleanups (list
, dont_do
, in_fixup
, reachable
)
4211 for (tail
= list
; tail
; tail
= TREE_CHAIN (tail
))
4212 if (dont_do
== 0 || TREE_PURPOSE (tail
) != dont_do
)
4214 if (TREE_CODE (TREE_VALUE (tail
)) == TREE_LIST
)
4215 expand_cleanups (TREE_VALUE (tail
), dont_do
, in_fixup
, reachable
);
4218 if (! in_fixup
&& using_eh_for_cleanups_p
)
4219 expand_eh_region_end_cleanup (TREE_VALUE (tail
));
4223 /* Cleanups may be run multiple times. For example,
4224 when exiting a binding contour, we expand the
4225 cleanups associated with that contour. When a goto
4226 within that binding contour has a target outside that
4227 contour, it will expand all cleanups from its scope to
4228 the target. Though the cleanups are expanded multiple
4229 times, the control paths are non-overlapping so the
4230 cleanups will not be executed twice. */
4232 /* We may need to protect from outer cleanups. */
4233 if (in_fixup
&& using_eh_for_cleanups_p
)
4235 expand_eh_region_start ();
4237 expand_expr (TREE_VALUE (tail
), const0_rtx
, VOIDmode
, 0);
4239 expand_eh_region_end_fixup (TREE_VALUE (tail
));
4242 expand_expr (TREE_VALUE (tail
), const0_rtx
, VOIDmode
, 0);
4250 /* Mark when the context we are emitting RTL for as a conditional
4251 context, so that any cleanup actions we register with
4252 expand_decl_init will be properly conditionalized when those
4253 cleanup actions are later performed. Must be called before any
4254 expression (tree) is expanded that is within a conditional context. */
4257 start_cleanup_deferral ()
4259 /* block_stack can be NULL if we are inside the parameter list. It is
4260 OK to do nothing, because cleanups aren't possible here. */
4262 ++block_stack
->data
.block
.conditional_code
;
4265 /* Mark the end of a conditional region of code. Because cleanup
4266 deferrals may be nested, we may still be in a conditional region
4267 after we end the currently deferred cleanups, only after we end all
4268 deferred cleanups, are we back in unconditional code. */
4271 end_cleanup_deferral ()
4273 /* block_stack can be NULL if we are inside the parameter list. It is
4274 OK to do nothing, because cleanups aren't possible here. */
4276 --block_stack
->data
.block
.conditional_code
;
4279 /* Move all cleanups from the current block_stack
4280 to the containing block_stack, where they are assumed to
4281 have been created. If anything can cause a temporary to
4282 be created, but not expanded for more than one level of
4283 block_stacks, then this code will have to change. */
4288 struct nesting
*block
= block_stack
;
4289 struct nesting
*outer
= block
->next
;
4291 outer
->data
.block
.cleanups
4292 = chainon (block
->data
.block
.cleanups
,
4293 outer
->data
.block
.cleanups
);
4294 block
->data
.block
.cleanups
= 0;
4298 last_cleanup_this_contour ()
4300 if (block_stack
== 0)
4303 return block_stack
->data
.block
.cleanups
;
4306 /* Return 1 if there are any pending cleanups at this point.
4307 If THIS_CONTOUR is nonzero, check the current contour as well.
4308 Otherwise, look only at the contours that enclose this one. */
4311 any_pending_cleanups (this_contour
)
4314 struct nesting
*block
;
4316 if (cfun
== NULL
|| cfun
->stmt
== NULL
|| block_stack
== 0)
4319 if (this_contour
&& block_stack
->data
.block
.cleanups
!= NULL
)
4321 if (block_stack
->data
.block
.cleanups
== 0
4322 && block_stack
->data
.block
.outer_cleanups
== 0)
4325 for (block
= block_stack
->next
; block
; block
= block
->next
)
4326 if (block
->data
.block
.cleanups
!= 0)
4332 /* Enter a case (Pascal) or switch (C) statement.
4333 Push a block onto case_stack and nesting_stack
4334 to accumulate the case-labels that are seen
4335 and to record the labels generated for the statement.
4337 EXIT_FLAG is nonzero if `exit_something' should exit this case stmt.
4338 Otherwise, this construct is transparent for `exit_something'.
4340 EXPR is the index-expression to be dispatched on.
4341 TYPE is its nominal type. We could simply convert EXPR to this type,
4342 but instead we take short cuts. */
4345 expand_start_case (exit_flag
, expr
, type
, printname
)
4349 const char *printname
;
4351 register struct nesting
*thiscase
= ALLOC_NESTING ();
4353 /* Make an entry on case_stack for the case we are entering. */
4355 thiscase
->next
= case_stack
;
4356 thiscase
->all
= nesting_stack
;
4357 thiscase
->depth
= ++nesting_depth
;
4358 thiscase
->exit_label
= exit_flag
? gen_label_rtx () : 0;
4359 thiscase
->data
.case_stmt
.case_list
= 0;
4360 thiscase
->data
.case_stmt
.index_expr
= expr
;
4361 thiscase
->data
.case_stmt
.nominal_type
= type
;
4362 thiscase
->data
.case_stmt
.default_label
= 0;
4363 thiscase
->data
.case_stmt
.printname
= printname
;
4364 thiscase
->data
.case_stmt
.line_number_status
= force_line_numbers ();
4365 case_stack
= thiscase
;
4366 nesting_stack
= thiscase
;
4368 do_pending_stack_adjust ();
4370 /* Make sure case_stmt.start points to something that won't
4371 need any transformation before expand_end_case. */
4372 if (GET_CODE (get_last_insn ()) != NOTE
)
4373 emit_note (NULL
, NOTE_INSN_DELETED
);
4375 thiscase
->data
.case_stmt
.start
= get_last_insn ();
4377 start_cleanup_deferral ();
4380 /* Start a "dummy case statement" within which case labels are invalid
4381 and are not connected to any larger real case statement.
4382 This can be used if you don't want to let a case statement jump
4383 into the middle of certain kinds of constructs. */
4386 expand_start_case_dummy ()
4388 register struct nesting
*thiscase
= ALLOC_NESTING ();
4390 /* Make an entry on case_stack for the dummy. */
4392 thiscase
->next
= case_stack
;
4393 thiscase
->all
= nesting_stack
;
4394 thiscase
->depth
= ++nesting_depth
;
4395 thiscase
->exit_label
= 0;
4396 thiscase
->data
.case_stmt
.case_list
= 0;
4397 thiscase
->data
.case_stmt
.start
= 0;
4398 thiscase
->data
.case_stmt
.nominal_type
= 0;
4399 thiscase
->data
.case_stmt
.default_label
= 0;
4400 case_stack
= thiscase
;
4401 nesting_stack
= thiscase
;
4402 start_cleanup_deferral ();
4405 /* End a dummy case statement. */
4408 expand_end_case_dummy ()
4410 end_cleanup_deferral ();
4411 POPSTACK (case_stack
);
4414 /* Return the data type of the index-expression
4415 of the innermost case statement, or null if none. */
4418 case_index_expr_type ()
4421 return TREE_TYPE (case_stack
->data
.case_stmt
.index_expr
);
4428 /* If this is the first label, warn if any insns have been emitted. */
4429 if (case_stack
->data
.case_stmt
.line_number_status
>= 0)
4433 restore_line_number_status
4434 (case_stack
->data
.case_stmt
.line_number_status
);
4435 case_stack
->data
.case_stmt
.line_number_status
= -1;
4437 for (insn
= case_stack
->data
.case_stmt
.start
;
4439 insn
= NEXT_INSN (insn
))
4441 if (GET_CODE (insn
) == CODE_LABEL
)
4443 if (GET_CODE (insn
) != NOTE
4444 && (GET_CODE (insn
) != INSN
|| GET_CODE (PATTERN (insn
)) != USE
))
4447 insn
= PREV_INSN (insn
);
4448 while (insn
&& (GET_CODE (insn
) != NOTE
|| NOTE_LINE_NUMBER (insn
) < 0));
4450 /* If insn is zero, then there must have been a syntax error. */
4452 warning_with_file_and_line (NOTE_SOURCE_FILE (insn
),
4453 NOTE_LINE_NUMBER (insn
),
4454 "unreachable code at beginning of %s",
4455 case_stack
->data
.case_stmt
.printname
);
4462 /* Accumulate one case or default label inside a case or switch statement.
4463 VALUE is the value of the case (a null pointer, for a default label).
4464 The function CONVERTER, when applied to arguments T and V,
4465 converts the value V to the type T.
4467 If not currently inside a case or switch statement, return 1 and do
4468 nothing. The caller will print a language-specific error message.
4469 If VALUE is a duplicate or overlaps, return 2 and do nothing
4470 except store the (first) duplicate node in *DUPLICATE.
4471 If VALUE is out of range, return 3 and do nothing.
4472 If we are jumping into the scope of a cleanup or var-sized array, return 5.
4473 Return 0 on success.
4475 Extended to handle range statements. */
4478 pushcase (value
, converter
, label
, duplicate
)
4479 register tree value
;
4480 tree (*converter
) PARAMS ((tree
, tree
));
4481 register tree label
;
4487 /* Fail if not inside a real case statement. */
4488 if (! (case_stack
&& case_stack
->data
.case_stmt
.start
))
4491 if (stack_block_stack
4492 && stack_block_stack
->depth
> case_stack
->depth
)
4495 index_type
= TREE_TYPE (case_stack
->data
.case_stmt
.index_expr
);
4496 nominal_type
= case_stack
->data
.case_stmt
.nominal_type
;
4498 /* If the index is erroneous, avoid more problems: pretend to succeed. */
4499 if (index_type
== error_mark_node
)
4502 /* Convert VALUE to the type in which the comparisons are nominally done. */
4504 value
= (*converter
) (nominal_type
, value
);
4508 /* Fail if this value is out of range for the actual type of the index
4509 (which may be narrower than NOMINAL_TYPE). */
4511 && (TREE_CONSTANT_OVERFLOW (value
)
4512 || ! int_fits_type_p (value
, index_type
)))
4515 return add_case_node (value
, value
, label
, duplicate
);
4518 /* Like pushcase but this case applies to all values between VALUE1 and
4519 VALUE2 (inclusive). If VALUE1 is NULL, the range starts at the lowest
4520 value of the index type and ends at VALUE2. If VALUE2 is NULL, the range
4521 starts at VALUE1 and ends at the highest value of the index type.
4522 If both are NULL, this case applies to all values.
4524 The return value is the same as that of pushcase but there is one
4525 additional error code: 4 means the specified range was empty. */
4528 pushcase_range (value1
, value2
, converter
, label
, duplicate
)
4529 register tree value1
, value2
;
4530 tree (*converter
) PARAMS ((tree
, tree
));
4531 register tree label
;
4537 /* Fail if not inside a real case statement. */
4538 if (! (case_stack
&& case_stack
->data
.case_stmt
.start
))
4541 if (stack_block_stack
4542 && stack_block_stack
->depth
> case_stack
->depth
)
4545 index_type
= TREE_TYPE (case_stack
->data
.case_stmt
.index_expr
);
4546 nominal_type
= case_stack
->data
.case_stmt
.nominal_type
;
4548 /* If the index is erroneous, avoid more problems: pretend to succeed. */
4549 if (index_type
== error_mark_node
)
4554 /* Convert VALUEs to type in which the comparisons are nominally done
4555 and replace any unspecified value with the corresponding bound. */
4557 value1
= TYPE_MIN_VALUE (index_type
);
4559 value2
= TYPE_MAX_VALUE (index_type
);
4561 /* Fail if the range is empty. Do this before any conversion since
4562 we want to allow out-of-range empty ranges. */
4563 if (value2
!= 0 && tree_int_cst_lt (value2
, value1
))
4566 /* If the max was unbounded, use the max of the nominal_type we are
4567 converting to. Do this after the < check above to suppress false
4570 value2
= TYPE_MAX_VALUE (nominal_type
);
4572 value1
= (*converter
) (nominal_type
, value1
);
4573 value2
= (*converter
) (nominal_type
, value2
);
4575 /* Fail if these values are out of range. */
4576 if (TREE_CONSTANT_OVERFLOW (value1
)
4577 || ! int_fits_type_p (value1
, index_type
))
4580 if (TREE_CONSTANT_OVERFLOW (value2
)
4581 || ! int_fits_type_p (value2
, index_type
))
4584 return add_case_node (value1
, value2
, label
, duplicate
);
4587 /* Do the actual insertion of a case label for pushcase and pushcase_range
4588 into case_stack->data.case_stmt.case_list. Use an AVL tree to avoid
4589 slowdown for large switch statements. */
4592 add_case_node (low
, high
, label
, duplicate
)
4597 struct case_node
*p
, **q
, *r
;
4599 /* If there's no HIGH value, then this is not a case range; it's
4600 just a simple case label. But that's just a degenerate case
4605 /* Handle default labels specially. */
4608 if (case_stack
->data
.case_stmt
.default_label
!= 0)
4610 *duplicate
= case_stack
->data
.case_stmt
.default_label
;
4613 case_stack
->data
.case_stmt
.default_label
= label
;
4614 expand_label (label
);
4618 q
= &case_stack
->data
.case_stmt
.case_list
;
4625 /* Keep going past elements distinctly greater than HIGH. */
4626 if (tree_int_cst_lt (high
, p
->low
))
4629 /* or distinctly less than LOW. */
4630 else if (tree_int_cst_lt (p
->high
, low
))
4635 /* We have an overlap; this is an error. */
4636 *duplicate
= p
->code_label
;
4641 /* Add this label to the chain, and succeed. */
4643 r
= (struct case_node
*) xmalloc (sizeof (struct case_node
));
4646 /* If the bounds are equal, turn this into the one-value case. */
4647 if (tree_int_cst_equal (low
, high
))
4652 r
->code_label
= label
;
4653 expand_label (label
);
4663 struct case_node
*s
;
4669 if (! (b
= p
->balance
))
4670 /* Growth propagation from left side. */
4677 if ((p
->left
= s
= r
->right
))
4686 if ((r
->parent
= s
))
4694 case_stack
->data
.case_stmt
.case_list
= r
;
4697 /* r->balance == +1 */
4702 struct case_node
*t
= r
->right
;
4704 if ((p
->left
= s
= t
->right
))
4708 if ((r
->right
= s
= t
->left
))
4722 if ((t
->parent
= s
))
4730 case_stack
->data
.case_stmt
.case_list
= t
;
4737 /* p->balance == +1; growth of left side balances the node. */
4747 if (! (b
= p
->balance
))
4748 /* Growth propagation from right side. */
4756 if ((p
->right
= s
= r
->left
))
4764 if ((r
->parent
= s
))
4773 case_stack
->data
.case_stmt
.case_list
= r
;
4777 /* r->balance == -1 */
4781 struct case_node
*t
= r
->left
;
4783 if ((p
->right
= s
= t
->left
))
4788 if ((r
->left
= s
= t
->right
))
4802 if ((t
->parent
= s
))
4811 case_stack
->data
.case_stmt
.case_list
= t
;
4817 /* p->balance == -1; growth of right side balances the node. */
4830 /* Returns the number of possible values of TYPE.
4831 Returns -1 if the number is unknown, variable, or if the number does not
4832 fit in a HOST_WIDE_INT.
4833 Sets *SPARENESS to 2 if TYPE is an ENUMERAL_TYPE whose values
4834 do not increase monotonically (there may be duplicates);
4835 to 1 if the values increase monotonically, but not always by 1;
4836 otherwise sets it to 0. */
4839 all_cases_count (type
, spareness
)
4844 HOST_WIDE_INT count
, minval
, lastval
;
4848 switch (TREE_CODE (type
))
4855 count
= 1 << BITS_PER_UNIT
;
4860 if (TYPE_MAX_VALUE (type
) != 0
4861 && 0 != (t
= fold (build (MINUS_EXPR
, type
, TYPE_MAX_VALUE (type
),
4862 TYPE_MIN_VALUE (type
))))
4863 && 0 != (t
= fold (build (PLUS_EXPR
, type
, t
,
4864 convert (type
, integer_zero_node
))))
4865 && host_integerp (t
, 1))
4866 count
= tree_low_cst (t
, 1);
4872 /* Don't waste time with enumeral types with huge values. */
4873 if (! host_integerp (TYPE_MIN_VALUE (type
), 0)
4874 || TYPE_MAX_VALUE (type
) == 0
4875 || ! host_integerp (TYPE_MAX_VALUE (type
), 0))
4878 lastval
= minval
= tree_low_cst (TYPE_MIN_VALUE (type
), 0);
4881 for (t
= TYPE_VALUES (type
); t
!= NULL_TREE
; t
= TREE_CHAIN (t
))
4883 HOST_WIDE_INT thisval
= tree_low_cst (TREE_VALUE (t
), 0);
4885 if (*spareness
== 2 || thisval
< lastval
)
4887 else if (thisval
!= minval
+ count
)
4897 #define BITARRAY_TEST(ARRAY, INDEX) \
4898 ((ARRAY)[(unsigned) (INDEX) / HOST_BITS_PER_CHAR]\
4899 & (1 << ((unsigned) (INDEX) % HOST_BITS_PER_CHAR)))
4900 #define BITARRAY_SET(ARRAY, INDEX) \
4901 ((ARRAY)[(unsigned) (INDEX) / HOST_BITS_PER_CHAR]\
4902 |= 1 << ((unsigned) (INDEX) % HOST_BITS_PER_CHAR))
4904 /* Set the elements of the bitstring CASES_SEEN (which has length COUNT),
4905 with the case values we have seen, assuming the case expression
4907 SPARSENESS is as determined by all_cases_count.
4909 The time needed is proportional to COUNT, unless
4910 SPARSENESS is 2, in which case quadratic time is needed. */
4913 mark_seen_cases (type
, cases_seen
, count
, sparseness
)
4915 unsigned char *cases_seen
;
4916 HOST_WIDE_INT count
;
4919 tree next_node_to_try
= NULL_TREE
;
4920 HOST_WIDE_INT next_node_offset
= 0;
4922 register struct case_node
*n
, *root
= case_stack
->data
.case_stmt
.case_list
;
4923 tree val
= make_node (INTEGER_CST
);
4925 TREE_TYPE (val
) = type
;
4929 else if (sparseness
== 2)
4932 unsigned HOST_WIDE_INT xlo
;
4934 /* This less efficient loop is only needed to handle
4935 duplicate case values (multiple enum constants
4936 with the same value). */
4937 TREE_TYPE (val
) = TREE_TYPE (root
->low
);
4938 for (t
= TYPE_VALUES (type
), xlo
= 0; t
!= NULL_TREE
;
4939 t
= TREE_CHAIN (t
), xlo
++)
4941 TREE_INT_CST_LOW (val
) = TREE_INT_CST_LOW (TREE_VALUE (t
));
4942 TREE_INT_CST_HIGH (val
) = TREE_INT_CST_HIGH (TREE_VALUE (t
));
4946 /* Keep going past elements distinctly greater than VAL. */
4947 if (tree_int_cst_lt (val
, n
->low
))
4950 /* or distinctly less than VAL. */
4951 else if (tree_int_cst_lt (n
->high
, val
))
4956 /* We have found a matching range. */
4957 BITARRAY_SET (cases_seen
, xlo
);
4967 case_stack
->data
.case_stmt
.case_list
= root
= case_tree2list (root
, 0);
4969 for (n
= root
; n
; n
= n
->right
)
4971 TREE_INT_CST_LOW (val
) = TREE_INT_CST_LOW (n
->low
);
4972 TREE_INT_CST_HIGH (val
) = TREE_INT_CST_HIGH (n
->low
);
4973 while (! tree_int_cst_lt (n
->high
, val
))
4975 /* Calculate (into xlo) the "offset" of the integer (val).
4976 The element with lowest value has offset 0, the next smallest
4977 element has offset 1, etc. */
4979 unsigned HOST_WIDE_INT xlo
;
4983 if (sparseness
&& TYPE_VALUES (type
) != NULL_TREE
)
4985 /* The TYPE_VALUES will be in increasing order, so
4986 starting searching where we last ended. */
4987 t
= next_node_to_try
;
4988 xlo
= next_node_offset
;
4994 t
= TYPE_VALUES (type
);
4997 if (tree_int_cst_equal (val
, TREE_VALUE (t
)))
4999 next_node_to_try
= TREE_CHAIN (t
);
5000 next_node_offset
= xlo
+ 1;
5005 if (t
== next_node_to_try
)
5014 t
= TYPE_MIN_VALUE (type
);
5016 neg_double (TREE_INT_CST_LOW (t
), TREE_INT_CST_HIGH (t
),
5020 add_double (xlo
, xhi
,
5021 TREE_INT_CST_LOW (val
), TREE_INT_CST_HIGH (val
),
5025 if (xhi
== 0 && xlo
< (unsigned HOST_WIDE_INT
) count
)
5026 BITARRAY_SET (cases_seen
, xlo
);
5028 add_double (TREE_INT_CST_LOW (val
), TREE_INT_CST_HIGH (val
),
5030 &TREE_INT_CST_LOW (val
), &TREE_INT_CST_HIGH (val
));
5036 /* Called when the index of a switch statement is an enumerated type
5037 and there is no default label.
5039 Checks that all enumeration literals are covered by the case
5040 expressions of a switch. Also, warn if there are any extra
5041 switch cases that are *not* elements of the enumerated type.
5043 If all enumeration literals were covered by the case expressions,
5044 turn one of the expressions into the default expression since it should
5045 not be possible to fall through such a switch. */
5048 check_for_full_enumeration_handling (type
)
5051 register struct case_node
*n
;
5052 register tree chain
;
5053 #if 0 /* variable used by 'if 0'ed code below. */
5054 register struct case_node
**l
;
5058 /* True iff the selector type is a numbered set mode. */
5061 /* The number of possible selector values. */
5064 /* For each possible selector value. a one iff it has been matched
5065 by a case value alternative. */
5066 unsigned char *cases_seen
;
5068 /* The allocated size of cases_seen, in chars. */
5069 HOST_WIDE_INT bytes_needed
;
5074 size
= all_cases_count (type
, &sparseness
);
5075 bytes_needed
= (size
+ HOST_BITS_PER_CHAR
) / HOST_BITS_PER_CHAR
;
5077 if (size
> 0 && size
< 600000
5078 /* We deliberately use calloc here, not cmalloc, so that we can suppress
5079 this optimization if we don't have enough memory rather than
5080 aborting, as xmalloc would do. */
5082 (unsigned char *) really_call_calloc (bytes_needed
, 1)) != NULL
)
5085 tree v
= TYPE_VALUES (type
);
5087 /* The time complexity of this code is normally O(N), where
5088 N being the number of members in the enumerated type.
5089 However, if type is a ENUMERAL_TYPE whose values do not
5090 increase monotonically, O(N*log(N)) time may be needed. */
5092 mark_seen_cases (type
, cases_seen
, size
, sparseness
);
5094 for (i
= 0; v
!= NULL_TREE
&& i
< size
; i
++, v
= TREE_CHAIN (v
))
5095 if (BITARRAY_TEST (cases_seen
, i
) == 0)
5096 warning ("enumeration value `%s' not handled in switch",
5097 IDENTIFIER_POINTER (TREE_PURPOSE (v
)));
5102 /* Now we go the other way around; we warn if there are case
5103 expressions that don't correspond to enumerators. This can
5104 occur since C and C++ don't enforce type-checking of
5105 assignments to enumeration variables. */
5107 if (case_stack
->data
.case_stmt
.case_list
5108 && case_stack
->data
.case_stmt
.case_list
->left
)
5109 case_stack
->data
.case_stmt
.case_list
5110 = case_tree2list (case_stack
->data
.case_stmt
.case_list
, 0);
5112 for (n
= case_stack
->data
.case_stmt
.case_list
; n
; n
= n
->right
)
5114 for (chain
= TYPE_VALUES (type
);
5115 chain
&& !tree_int_cst_equal (n
->low
, TREE_VALUE (chain
));
5116 chain
= TREE_CHAIN (chain
))
5121 if (TYPE_NAME (type
) == 0)
5122 warning ("case value `%ld' not in enumerated type",
5123 (long) TREE_INT_CST_LOW (n
->low
));
5125 warning ("case value `%ld' not in enumerated type `%s'",
5126 (long) TREE_INT_CST_LOW (n
->low
),
5127 IDENTIFIER_POINTER ((TREE_CODE (TYPE_NAME (type
))
5130 : DECL_NAME (TYPE_NAME (type
))));
5132 if (!tree_int_cst_equal (n
->low
, n
->high
))
5134 for (chain
= TYPE_VALUES (type
);
5135 chain
&& !tree_int_cst_equal (n
->high
, TREE_VALUE (chain
));
5136 chain
= TREE_CHAIN (chain
))
5141 if (TYPE_NAME (type
) == 0)
5142 warning ("case value `%ld' not in enumerated type",
5143 (long) TREE_INT_CST_LOW (n
->high
));
5145 warning ("case value `%ld' not in enumerated type `%s'",
5146 (long) TREE_INT_CST_LOW (n
->high
),
5147 IDENTIFIER_POINTER ((TREE_CODE (TYPE_NAME (type
))
5150 : DECL_NAME (TYPE_NAME (type
))));
5156 /* ??? This optimization is disabled because it causes valid programs to
5157 fail. ANSI C does not guarantee that an expression with enum type
5158 will have a value that is the same as one of the enumeration literals. */
5160 /* If all values were found as case labels, make one of them the default
5161 label. Thus, this switch will never fall through. We arbitrarily pick
5162 the last one to make the default since this is likely the most
5163 efficient choice. */
5167 for (l
= &case_stack
->data
.case_stmt
.case_list
;
5172 case_stack
->data
.case_stmt
.default_label
= (*l
)->code_label
;
5178 /* Free CN, and its children. */
5181 free_case_nodes (cn
)
5186 free_case_nodes (cn
->left
);
5187 free_case_nodes (cn
->right
);
5193 /* Terminate a case (Pascal) or switch (C) statement
5194 in which ORIG_INDEX is the expression to be tested.
5195 Generate the code to test it and jump to the right place. */
5198 expand_end_case (orig_index
)
5201 tree minval
= NULL_TREE
, maxval
= NULL_TREE
, range
= NULL_TREE
, orig_minval
;
5202 rtx default_label
= 0;
5203 register struct case_node
*n
;
5211 register struct nesting
*thiscase
= case_stack
;
5212 tree index_expr
, index_type
;
5215 /* Don't crash due to previous errors. */
5216 if (thiscase
== NULL
)
5219 table_label
= gen_label_rtx ();
5220 index_expr
= thiscase
->data
.case_stmt
.index_expr
;
5221 index_type
= TREE_TYPE (index_expr
);
5222 unsignedp
= TREE_UNSIGNED (index_type
);
5224 do_pending_stack_adjust ();
5226 /* This might get an spurious warning in the presence of a syntax error;
5227 it could be fixed by moving the call to check_seenlabel after the
5228 check for error_mark_node, and copying the code of check_seenlabel that
5229 deals with case_stack->data.case_stmt.line_number_status /
5230 restore_line_number_status in front of the call to end_cleanup_deferral;
5231 However, this might miss some useful warnings in the presence of
5232 non-syntax errors. */
5235 /* An ERROR_MARK occurs for various reasons including invalid data type. */
5236 if (index_type
!= error_mark_node
)
5238 /* If switch expression was an enumerated type, check that all
5239 enumeration literals are covered by the cases.
5240 No sense trying this if there's a default case, however. */
5242 if (!thiscase
->data
.case_stmt
.default_label
5243 && TREE_CODE (TREE_TYPE (orig_index
)) == ENUMERAL_TYPE
5244 && TREE_CODE (index_expr
) != INTEGER_CST
)
5245 check_for_full_enumeration_handling (TREE_TYPE (orig_index
));
5247 /* If we don't have a default-label, create one here,
5248 after the body of the switch. */
5249 if (thiscase
->data
.case_stmt
.default_label
== 0)
5251 thiscase
->data
.case_stmt
.default_label
5252 = build_decl (LABEL_DECL
, NULL_TREE
, NULL_TREE
);
5253 expand_label (thiscase
->data
.case_stmt
.default_label
);
5255 default_label
= label_rtx (thiscase
->data
.case_stmt
.default_label
);
5257 before_case
= get_last_insn ();
5259 if (thiscase
->data
.case_stmt
.case_list
5260 && thiscase
->data
.case_stmt
.case_list
->left
)
5261 thiscase
->data
.case_stmt
.case_list
5262 = case_tree2list (thiscase
->data
.case_stmt
.case_list
, 0);
5264 /* Simplify the case-list before we count it. */
5265 group_case_nodes (thiscase
->data
.case_stmt
.case_list
);
5267 /* Get upper and lower bounds of case values.
5268 Also convert all the case values to the index expr's data type. */
5271 for (n
= thiscase
->data
.case_stmt
.case_list
; n
; n
= n
->right
)
5273 /* Check low and high label values are integers. */
5274 if (TREE_CODE (n
->low
) != INTEGER_CST
)
5276 if (TREE_CODE (n
->high
) != INTEGER_CST
)
5279 n
->low
= convert (index_type
, n
->low
);
5280 n
->high
= convert (index_type
, n
->high
);
5282 /* Count the elements and track the largest and smallest
5283 of them (treating them as signed even if they are not). */
5291 if (INT_CST_LT (n
->low
, minval
))
5293 if (INT_CST_LT (maxval
, n
->high
))
5296 /* A range counts double, since it requires two compares. */
5297 if (! tree_int_cst_equal (n
->low
, n
->high
))
5301 orig_minval
= minval
;
5303 /* Compute span of values. */
5305 range
= fold (build (MINUS_EXPR
, index_type
, maxval
, minval
));
5307 end_cleanup_deferral ();
5311 expand_expr (index_expr
, const0_rtx
, VOIDmode
, 0);
5313 emit_jump (default_label
);
5316 /* If range of values is much bigger than number of values,
5317 make a sequence of conditional branches instead of a dispatch.
5318 If the switch-index is a constant, do it this way
5319 because we can optimize it. */
5321 #ifndef CASE_VALUES_THRESHOLD
5323 #define CASE_VALUES_THRESHOLD (HAVE_casesi ? 4 : 5)
5325 /* If machine does not have a case insn that compares the
5326 bounds, this means extra overhead for dispatch tables
5327 which raises the threshold for using them. */
5328 #define CASE_VALUES_THRESHOLD 5
5329 #endif /* HAVE_casesi */
5330 #endif /* CASE_VALUES_THRESHOLD */
5332 else if (count
< CASE_VALUES_THRESHOLD
5333 || compare_tree_int (range
, 10 * count
) > 0
5334 /* RANGE may be signed, and really large ranges will show up
5335 as negative numbers. */
5336 || compare_tree_int (range
, 0) < 0
5337 #ifndef ASM_OUTPUT_ADDR_DIFF_ELT
5340 || TREE_CODE (index_expr
) == INTEGER_CST
5341 /* These will reduce to a constant. */
5342 || (TREE_CODE (index_expr
) == CALL_EXPR
5343 && TREE_CODE (TREE_OPERAND (index_expr
, 0)) == ADDR_EXPR
5344 && TREE_CODE (TREE_OPERAND (TREE_OPERAND (index_expr
, 0), 0)) == FUNCTION_DECL
5345 && DECL_BUILT_IN_CLASS (TREE_OPERAND (TREE_OPERAND (index_expr
, 0), 0)) == BUILT_IN_NORMAL
5346 && DECL_FUNCTION_CODE (TREE_OPERAND (TREE_OPERAND (index_expr
, 0), 0)) == BUILT_IN_CLASSIFY_TYPE
)
5347 || (TREE_CODE (index_expr
) == COMPOUND_EXPR
5348 && TREE_CODE (TREE_OPERAND (index_expr
, 1)) == INTEGER_CST
))
5350 index
= expand_expr (index_expr
, NULL_RTX
, VOIDmode
, 0);
5352 /* If the index is a short or char that we do not have
5353 an insn to handle comparisons directly, convert it to
5354 a full integer now, rather than letting each comparison
5355 generate the conversion. */
5357 if (GET_MODE_CLASS (GET_MODE (index
)) == MODE_INT
5358 && (cmp_optab
->handlers
[(int) GET_MODE (index
)].insn_code
5359 == CODE_FOR_nothing
))
5361 enum machine_mode wider_mode
;
5362 for (wider_mode
= GET_MODE (index
); wider_mode
!= VOIDmode
;
5363 wider_mode
= GET_MODE_WIDER_MODE (wider_mode
))
5364 if (cmp_optab
->handlers
[(int) wider_mode
].insn_code
5365 != CODE_FOR_nothing
)
5367 index
= convert_to_mode (wider_mode
, index
, unsignedp
);
5373 do_pending_stack_adjust ();
5375 index
= protect_from_queue (index
, 0);
5376 if (GET_CODE (index
) == MEM
)
5377 index
= copy_to_reg (index
);
5378 if (GET_CODE (index
) == CONST_INT
5379 || TREE_CODE (index_expr
) == INTEGER_CST
)
5381 /* Make a tree node with the proper constant value
5382 if we don't already have one. */
5383 if (TREE_CODE (index_expr
) != INTEGER_CST
)
5386 = build_int_2 (INTVAL (index
),
5387 unsignedp
|| INTVAL (index
) >= 0 ? 0 : -1);
5388 index_expr
= convert (index_type
, index_expr
);
5391 /* For constant index expressions we need only
5392 issue a unconditional branch to the appropriate
5393 target code. The job of removing any unreachable
5394 code is left to the optimisation phase if the
5395 "-O" option is specified. */
5396 for (n
= thiscase
->data
.case_stmt
.case_list
; n
; n
= n
->right
)
5397 if (! tree_int_cst_lt (index_expr
, n
->low
)
5398 && ! tree_int_cst_lt (n
->high
, index_expr
))
5402 emit_jump (label_rtx (n
->code_label
));
5404 emit_jump (default_label
);
5408 /* If the index expression is not constant we generate
5409 a binary decision tree to select the appropriate
5410 target code. This is done as follows:
5412 The list of cases is rearranged into a binary tree,
5413 nearly optimal assuming equal probability for each case.
5415 The tree is transformed into RTL, eliminating
5416 redundant test conditions at the same time.
5418 If program flow could reach the end of the
5419 decision tree an unconditional jump to the
5420 default code is emitted. */
5423 = (TREE_CODE (TREE_TYPE (orig_index
)) != ENUMERAL_TYPE
5424 && estimate_case_costs (thiscase
->data
.case_stmt
.case_list
));
5425 balance_case_nodes (&thiscase
->data
.case_stmt
.case_list
, NULL
);
5426 emit_case_nodes (index
, thiscase
->data
.case_stmt
.case_list
,
5427 default_label
, index_type
);
5428 emit_jump_if_reachable (default_label
);
5437 enum machine_mode index_mode
= SImode
;
5438 int index_bits
= GET_MODE_BITSIZE (index_mode
);
5440 enum machine_mode op_mode
;
5442 /* Convert the index to SImode. */
5443 if (GET_MODE_BITSIZE (TYPE_MODE (index_type
))
5444 > GET_MODE_BITSIZE (index_mode
))
5446 enum machine_mode omode
= TYPE_MODE (index_type
);
5447 rtx rangertx
= expand_expr (range
, NULL_RTX
, VOIDmode
, 0);
5449 /* We must handle the endpoints in the original mode. */
5450 index_expr
= build (MINUS_EXPR
, index_type
,
5451 index_expr
, minval
);
5452 minval
= integer_zero_node
;
5453 index
= expand_expr (index_expr
, NULL_RTX
, VOIDmode
, 0);
5454 emit_cmp_and_jump_insns (rangertx
, index
, LTU
, NULL_RTX
,
5455 omode
, 1, 0, default_label
);
5456 /* Now we can safely truncate. */
5457 index
= convert_to_mode (index_mode
, index
, 0);
5461 if (TYPE_MODE (index_type
) != index_mode
)
5463 index_expr
= convert (type_for_size (index_bits
, 0),
5465 index_type
= TREE_TYPE (index_expr
);
5468 index
= expand_expr (index_expr
, NULL_RTX
, VOIDmode
, 0);
5471 index
= protect_from_queue (index
, 0);
5472 do_pending_stack_adjust ();
5474 op_mode
= insn_data
[(int) CODE_FOR_casesi
].operand
[0].mode
;
5475 if (! (*insn_data
[(int) CODE_FOR_casesi
].operand
[0].predicate
)
5477 index
= copy_to_mode_reg (op_mode
, index
);
5479 op1
= expand_expr (minval
, NULL_RTX
, VOIDmode
, 0);
5481 op_mode
= insn_data
[(int) CODE_FOR_casesi
].operand
[1].mode
;
5482 op1
= convert_modes (op_mode
, TYPE_MODE (TREE_TYPE (minval
)),
5483 op1
, TREE_UNSIGNED (TREE_TYPE (minval
)));
5484 if (! (*insn_data
[(int) CODE_FOR_casesi
].operand
[1].predicate
)
5486 op1
= copy_to_mode_reg (op_mode
, op1
);
5488 op2
= expand_expr (range
, NULL_RTX
, VOIDmode
, 0);
5490 op_mode
= insn_data
[(int) CODE_FOR_casesi
].operand
[2].mode
;
5491 op2
= convert_modes (op_mode
, TYPE_MODE (TREE_TYPE (range
)),
5492 op2
, TREE_UNSIGNED (TREE_TYPE (range
)));
5493 if (! (*insn_data
[(int) CODE_FOR_casesi
].operand
[2].predicate
)
5495 op2
= copy_to_mode_reg (op_mode
, op2
);
5497 emit_jump_insn (gen_casesi (index
, op1
, op2
,
5498 table_label
, default_label
));
5502 #ifdef HAVE_tablejump
5503 if (! win
&& HAVE_tablejump
)
5505 index_type
= thiscase
->data
.case_stmt
.nominal_type
;
5506 index_expr
= fold (build (MINUS_EXPR
, index_type
,
5507 convert (index_type
, index_expr
),
5508 convert (index_type
, minval
)));
5509 index
= expand_expr (index_expr
, NULL_RTX
, VOIDmode
, 0);
5511 index
= protect_from_queue (index
, 0);
5512 do_pending_stack_adjust ();
5514 do_tablejump (index
, TYPE_MODE (index_type
),
5515 convert_modes (TYPE_MODE (index_type
),
5516 TYPE_MODE (TREE_TYPE (range
)),
5517 expand_expr (range
, NULL_RTX
,
5519 TREE_UNSIGNED (TREE_TYPE (range
))),
5520 table_label
, default_label
);
5527 /* Get table of labels to jump to, in order of case index. */
5529 ncases
= TREE_INT_CST_LOW (range
) + 1;
5530 labelvec
= (rtx
*) alloca (ncases
* sizeof (rtx
));
5531 memset ((char *) labelvec
, 0, ncases
* sizeof (rtx
));
5533 for (n
= thiscase
->data
.case_stmt
.case_list
; n
; n
= n
->right
)
5535 register HOST_WIDE_INT i
5536 = TREE_INT_CST_LOW (n
->low
) - TREE_INT_CST_LOW (orig_minval
);
5541 = gen_rtx_LABEL_REF (Pmode
, label_rtx (n
->code_label
));
5542 if (i
+ TREE_INT_CST_LOW (orig_minval
)
5543 == TREE_INT_CST_LOW (n
->high
))
5549 /* Fill in the gaps with the default. */
5550 for (i
= 0; i
< ncases
; i
++)
5551 if (labelvec
[i
] == 0)
5552 labelvec
[i
] = gen_rtx_LABEL_REF (Pmode
, default_label
);
5554 /* Output the table */
5555 emit_label (table_label
);
5557 if (CASE_VECTOR_PC_RELATIVE
|| flag_pic
)
5558 emit_jump_insn (gen_rtx_ADDR_DIFF_VEC (CASE_VECTOR_MODE
,
5559 gen_rtx_LABEL_REF (Pmode
, table_label
),
5560 gen_rtvec_v (ncases
, labelvec
),
5561 const0_rtx
, const0_rtx
));
5563 emit_jump_insn (gen_rtx_ADDR_VEC (CASE_VECTOR_MODE
,
5564 gen_rtvec_v (ncases
, labelvec
)));
5566 /* If the case insn drops through the table,
5567 after the table we must jump to the default-label.
5568 Otherwise record no drop-through after the table. */
5569 #ifdef CASE_DROPS_THROUGH
5570 emit_jump (default_label
);
5576 before_case
= squeeze_notes (NEXT_INSN (before_case
), get_last_insn ());
5577 reorder_insns (before_case
, get_last_insn (),
5578 thiscase
->data
.case_stmt
.start
);
5581 end_cleanup_deferral ();
5583 if (thiscase
->exit_label
)
5584 emit_label (thiscase
->exit_label
);
5586 free_case_nodes (case_stack
->data
.case_stmt
.case_list
);
5587 POPSTACK (case_stack
);
5592 /* Convert the tree NODE into a list linked by the right field, with the left
5593 field zeroed. RIGHT is used for recursion; it is a list to be placed
5594 rightmost in the resulting list. */
5596 static struct case_node
*
5597 case_tree2list (node
, right
)
5598 struct case_node
*node
, *right
;
5600 struct case_node
*left
;
5603 right
= case_tree2list (node
->right
, right
);
5605 node
->right
= right
;
5606 if ((left
= node
->left
))
5609 return case_tree2list (left
, node
);
5615 /* Generate code to jump to LABEL if OP1 and OP2 are equal. */
5618 do_jump_if_equal (op1
, op2
, label
, unsignedp
)
5619 rtx op1
, op2
, label
;
5622 if (GET_CODE (op1
) == CONST_INT
5623 && GET_CODE (op2
) == CONST_INT
)
5625 if (INTVAL (op1
) == INTVAL (op2
))
5630 enum machine_mode mode
= GET_MODE (op1
);
5631 if (mode
== VOIDmode
)
5632 mode
= GET_MODE (op2
);
5633 emit_cmp_and_jump_insns (op1
, op2
, EQ
, NULL_RTX
, mode
, unsignedp
,
5638 /* Not all case values are encountered equally. This function
5639 uses a heuristic to weight case labels, in cases where that
5640 looks like a reasonable thing to do.
5642 Right now, all we try to guess is text, and we establish the
5645 chars above space: 16
5654 If we find any cases in the switch that are not either -1 or in the range
5655 of valid ASCII characters, or are control characters other than those
5656 commonly used with "\", don't treat this switch scanning text.
5658 Return 1 if these nodes are suitable for cost estimation, otherwise
5662 estimate_case_costs (node
)
5665 tree min_ascii
= integer_minus_one_node
;
5666 tree max_ascii
= convert (TREE_TYPE (node
->high
), build_int_2 (127, 0));
5670 /* If we haven't already made the cost table, make it now. Note that the
5671 lower bound of the table is -1, not zero. */
5673 if (! cost_table_initialized
)
5675 cost_table_initialized
= 1;
5677 for (i
= 0; i
< 128; i
++)
5680 COST_TABLE (i
) = 16;
5681 else if (ISPUNCT (i
))
5683 else if (ISCNTRL (i
))
5684 COST_TABLE (i
) = -1;
5687 COST_TABLE (' ') = 8;
5688 COST_TABLE ('\t') = 4;
5689 COST_TABLE ('\0') = 4;
5690 COST_TABLE ('\n') = 2;
5691 COST_TABLE ('\f') = 1;
5692 COST_TABLE ('\v') = 1;
5693 COST_TABLE ('\b') = 1;
5696 /* See if all the case expressions look like text. It is text if the
5697 constant is >= -1 and the highest constant is <= 127. Do all comparisons
5698 as signed arithmetic since we don't want to ever access cost_table with a
5699 value less than -1. Also check that none of the constants in a range
5700 are strange control characters. */
5702 for (n
= node
; n
; n
= n
->right
)
5704 if ((INT_CST_LT (n
->low
, min_ascii
)) || INT_CST_LT (max_ascii
, n
->high
))
5707 for (i
= (HOST_WIDE_INT
) TREE_INT_CST_LOW (n
->low
);
5708 i
<= (HOST_WIDE_INT
) TREE_INT_CST_LOW (n
->high
); i
++)
5709 if (COST_TABLE (i
) < 0)
5713 /* All interesting values are within the range of interesting
5714 ASCII characters. */
5718 /* Scan an ordered list of case nodes
5719 combining those with consecutive values or ranges.
5721 Eg. three separate entries 1: 2: 3: become one entry 1..3: */
5724 group_case_nodes (head
)
5727 case_node_ptr node
= head
;
5731 rtx lb
= next_real_insn (label_rtx (node
->code_label
));
5733 case_node_ptr np
= node
;
5735 /* Try to group the successors of NODE with NODE. */
5736 while (((np
= np
->right
) != 0)
5737 /* Do they jump to the same place? */
5738 && ((lb2
= next_real_insn (label_rtx (np
->code_label
))) == lb
5739 || (lb
!= 0 && lb2
!= 0
5740 && simplejump_p (lb
)
5741 && simplejump_p (lb2
)
5742 && rtx_equal_p (SET_SRC (PATTERN (lb
)),
5743 SET_SRC (PATTERN (lb2
)))))
5744 /* Are their ranges consecutive? */
5745 && tree_int_cst_equal (np
->low
,
5746 fold (build (PLUS_EXPR
,
5747 TREE_TYPE (node
->high
),
5750 /* An overflow is not consecutive. */
5751 && tree_int_cst_lt (node
->high
,
5752 fold (build (PLUS_EXPR
,
5753 TREE_TYPE (node
->high
),
5755 integer_one_node
))))
5757 node
->high
= np
->high
;
5759 /* NP is the first node after NODE which can't be grouped with it.
5760 Delete the nodes in between, and move on to that node. */
5766 /* Take an ordered list of case nodes
5767 and transform them into a near optimal binary tree,
5768 on the assumption that any target code selection value is as
5769 likely as any other.
5771 The transformation is performed by splitting the ordered
5772 list into two equal sections plus a pivot. The parts are
5773 then attached to the pivot as left and right branches. Each
5774 branch is then transformed recursively. */
5777 balance_case_nodes (head
, parent
)
5778 case_node_ptr
*head
;
5779 case_node_ptr parent
;
5781 register case_node_ptr np
;
5789 register case_node_ptr
*npp
;
5792 /* Count the number of entries on branch. Also count the ranges. */
5796 if (!tree_int_cst_equal (np
->low
, np
->high
))
5800 cost
+= COST_TABLE (TREE_INT_CST_LOW (np
->high
));
5804 cost
+= COST_TABLE (TREE_INT_CST_LOW (np
->low
));
5812 /* Split this list if it is long enough for that to help. */
5817 /* Find the place in the list that bisects the list's total cost,
5818 Here I gets half the total cost. */
5823 /* Skip nodes while their cost does not reach that amount. */
5824 if (!tree_int_cst_equal ((*npp
)->low
, (*npp
)->high
))
5825 i
-= COST_TABLE (TREE_INT_CST_LOW ((*npp
)->high
));
5826 i
-= COST_TABLE (TREE_INT_CST_LOW ((*npp
)->low
));
5829 npp
= &(*npp
)->right
;
5834 /* Leave this branch lopsided, but optimize left-hand
5835 side and fill in `parent' fields for right-hand side. */
5837 np
->parent
= parent
;
5838 balance_case_nodes (&np
->left
, np
);
5839 for (; np
->right
; np
= np
->right
)
5840 np
->right
->parent
= np
;
5844 /* If there are just three nodes, split at the middle one. */
5846 npp
= &(*npp
)->right
;
5849 /* Find the place in the list that bisects the list's total cost,
5850 where ranges count as 2.
5851 Here I gets half the total cost. */
5852 i
= (i
+ ranges
+ 1) / 2;
5855 /* Skip nodes while their cost does not reach that amount. */
5856 if (!tree_int_cst_equal ((*npp
)->low
, (*npp
)->high
))
5861 npp
= &(*npp
)->right
;
5866 np
->parent
= parent
;
5869 /* Optimize each of the two split parts. */
5870 balance_case_nodes (&np
->left
, np
);
5871 balance_case_nodes (&np
->right
, np
);
5875 /* Else leave this branch as one level,
5876 but fill in `parent' fields. */
5878 np
->parent
= parent
;
5879 for (; np
->right
; np
= np
->right
)
5880 np
->right
->parent
= np
;
5885 /* Search the parent sections of the case node tree
5886 to see if a test for the lower bound of NODE would be redundant.
5887 INDEX_TYPE is the type of the index expression.
5889 The instructions to generate the case decision tree are
5890 output in the same order as nodes are processed so it is
5891 known that if a parent node checks the range of the current
5892 node minus one that the current node is bounded at its lower
5893 span. Thus the test would be redundant. */
5896 node_has_low_bound (node
, index_type
)
5901 case_node_ptr pnode
;
5903 /* If the lower bound of this node is the lowest value in the index type,
5904 we need not test it. */
5906 if (tree_int_cst_equal (node
->low
, TYPE_MIN_VALUE (index_type
)))
5909 /* If this node has a left branch, the value at the left must be less
5910 than that at this node, so it cannot be bounded at the bottom and
5911 we need not bother testing any further. */
5916 low_minus_one
= fold (build (MINUS_EXPR
, TREE_TYPE (node
->low
),
5917 node
->low
, integer_one_node
));
5919 /* If the subtraction above overflowed, we can't verify anything.
5920 Otherwise, look for a parent that tests our value - 1. */
5922 if (! tree_int_cst_lt (low_minus_one
, node
->low
))
5925 for (pnode
= node
->parent
; pnode
; pnode
= pnode
->parent
)
5926 if (tree_int_cst_equal (low_minus_one
, pnode
->high
))
5932 /* Search the parent sections of the case node tree
5933 to see if a test for the upper bound of NODE would be redundant.
5934 INDEX_TYPE is the type of the index expression.
5936 The instructions to generate the case decision tree are
5937 output in the same order as nodes are processed so it is
5938 known that if a parent node checks the range of the current
5939 node plus one that the current node is bounded at its upper
5940 span. Thus the test would be redundant. */
5943 node_has_high_bound (node
, index_type
)
5948 case_node_ptr pnode
;
5950 /* If there is no upper bound, obviously no test is needed. */
5952 if (TYPE_MAX_VALUE (index_type
) == NULL
)
5955 /* If the upper bound of this node is the highest value in the type
5956 of the index expression, we need not test against it. */
5958 if (tree_int_cst_equal (node
->high
, TYPE_MAX_VALUE (index_type
)))
5961 /* If this node has a right branch, the value at the right must be greater
5962 than that at this node, so it cannot be bounded at the top and
5963 we need not bother testing any further. */
5968 high_plus_one
= fold (build (PLUS_EXPR
, TREE_TYPE (node
->high
),
5969 node
->high
, integer_one_node
));
5971 /* If the addition above overflowed, we can't verify anything.
5972 Otherwise, look for a parent that tests our value + 1. */
5974 if (! tree_int_cst_lt (node
->high
, high_plus_one
))
5977 for (pnode
= node
->parent
; pnode
; pnode
= pnode
->parent
)
5978 if (tree_int_cst_equal (high_plus_one
, pnode
->low
))
5984 /* Search the parent sections of the
5985 case node tree to see if both tests for the upper and lower
5986 bounds of NODE would be redundant. */
5989 node_is_bounded (node
, index_type
)
5993 return (node_has_low_bound (node
, index_type
)
5994 && node_has_high_bound (node
, index_type
));
5997 /* Emit an unconditional jump to LABEL unless it would be dead code. */
6000 emit_jump_if_reachable (label
)
6003 if (GET_CODE (get_last_insn ()) != BARRIER
)
6007 /* Emit step-by-step code to select a case for the value of INDEX.
6008 The thus generated decision tree follows the form of the
6009 case-node binary tree NODE, whose nodes represent test conditions.
6010 INDEX_TYPE is the type of the index of the switch.
6012 Care is taken to prune redundant tests from the decision tree
6013 by detecting any boundary conditions already checked by
6014 emitted rtx. (See node_has_high_bound, node_has_low_bound
6015 and node_is_bounded, above.)
6017 Where the test conditions can be shown to be redundant we emit
6018 an unconditional jump to the target code. As a further
6019 optimization, the subordinates of a tree node are examined to
6020 check for bounded nodes. In this case conditional and/or
6021 unconditional jumps as a result of the boundary check for the
6022 current node are arranged to target the subordinates associated
6023 code for out of bound conditions on the current node.
6025 We can assume that when control reaches the code generated here,
6026 the index value has already been compared with the parents
6027 of this node, and determined to be on the same side of each parent
6028 as this node is. Thus, if this node tests for the value 51,
6029 and a parent tested for 52, we don't need to consider
6030 the possibility of a value greater than 51. If another parent
6031 tests for the value 50, then this node need not test anything. */
6034 emit_case_nodes (index
, node
, default_label
, index_type
)
6040 /* If INDEX has an unsigned type, we must make unsigned branches. */
6041 int unsignedp
= TREE_UNSIGNED (index_type
);
6042 enum machine_mode mode
= GET_MODE (index
);
6043 enum machine_mode imode
= TYPE_MODE (index_type
);
6045 /* See if our parents have already tested everything for us.
6046 If they have, emit an unconditional jump for this node. */
6047 if (node_is_bounded (node
, index_type
))
6048 emit_jump (label_rtx (node
->code_label
));
6050 else if (tree_int_cst_equal (node
->low
, node
->high
))
6052 /* Node is single valued. First see if the index expression matches
6053 this node and then check our children, if any. */
6055 do_jump_if_equal (index
,
6056 convert_modes (mode
, imode
,
6057 expand_expr (node
->low
, NULL_RTX
,
6060 label_rtx (node
->code_label
), unsignedp
);
6062 if (node
->right
!= 0 && node
->left
!= 0)
6064 /* This node has children on both sides.
6065 Dispatch to one side or the other
6066 by comparing the index value with this node's value.
6067 If one subtree is bounded, check that one first,
6068 so we can avoid real branches in the tree. */
6070 if (node_is_bounded (node
->right
, index_type
))
6072 emit_cmp_and_jump_insns (index
,
6075 expand_expr (node
->high
, NULL_RTX
,
6078 GT
, NULL_RTX
, mode
, unsignedp
, 0,
6079 label_rtx (node
->right
->code_label
));
6080 emit_case_nodes (index
, node
->left
, default_label
, index_type
);
6083 else if (node_is_bounded (node
->left
, index_type
))
6085 emit_cmp_and_jump_insns (index
,
6088 expand_expr (node
->high
, NULL_RTX
,
6091 LT
, NULL_RTX
, mode
, unsignedp
, 0,
6092 label_rtx (node
->left
->code_label
));
6093 emit_case_nodes (index
, node
->right
, default_label
, index_type
);
6098 /* Neither node is bounded. First distinguish the two sides;
6099 then emit the code for one side at a time. */
6101 tree test_label
= build_decl (LABEL_DECL
, NULL_TREE
, NULL_TREE
);
6103 /* See if the value is on the right. */
6104 emit_cmp_and_jump_insns (index
,
6107 expand_expr (node
->high
, NULL_RTX
,
6110 GT
, NULL_RTX
, mode
, unsignedp
, 0,
6111 label_rtx (test_label
));
6113 /* Value must be on the left.
6114 Handle the left-hand subtree. */
6115 emit_case_nodes (index
, node
->left
, default_label
, index_type
);
6116 /* If left-hand subtree does nothing,
6118 emit_jump_if_reachable (default_label
);
6120 /* Code branches here for the right-hand subtree. */
6121 expand_label (test_label
);
6122 emit_case_nodes (index
, node
->right
, default_label
, index_type
);
6126 else if (node
->right
!= 0 && node
->left
== 0)
6128 /* Here we have a right child but no left so we issue conditional
6129 branch to default and process the right child.
6131 Omit the conditional branch to default if we it avoid only one
6132 right child; it costs too much space to save so little time. */
6134 if (node
->right
->right
|| node
->right
->left
6135 || !tree_int_cst_equal (node
->right
->low
, node
->right
->high
))
6137 if (!node_has_low_bound (node
, index_type
))
6139 emit_cmp_and_jump_insns (index
,
6142 expand_expr (node
->high
, NULL_RTX
,
6145 LT
, NULL_RTX
, mode
, unsignedp
, 0,
6149 emit_case_nodes (index
, node
->right
, default_label
, index_type
);
6152 /* We cannot process node->right normally
6153 since we haven't ruled out the numbers less than
6154 this node's value. So handle node->right explicitly. */
6155 do_jump_if_equal (index
,
6158 expand_expr (node
->right
->low
, NULL_RTX
,
6161 label_rtx (node
->right
->code_label
), unsignedp
);
6164 else if (node
->right
== 0 && node
->left
!= 0)
6166 /* Just one subtree, on the left. */
6168 #if 0 /* The following code and comment were formerly part
6169 of the condition here, but they didn't work
6170 and I don't understand what the idea was. -- rms. */
6171 /* If our "most probable entry" is less probable
6172 than the default label, emit a jump to
6173 the default label using condition codes
6174 already lying around. With no right branch,
6175 a branch-greater-than will get us to the default
6178 && COST_TABLE (TREE_INT_CST_LOW (node
->high
)) < 12)
6181 if (node
->left
->left
|| node
->left
->right
6182 || !tree_int_cst_equal (node
->left
->low
, node
->left
->high
))
6184 if (!node_has_high_bound (node
, index_type
))
6186 emit_cmp_and_jump_insns (index
,
6189 expand_expr (node
->high
, NULL_RTX
,
6192 GT
, NULL_RTX
, mode
, unsignedp
, 0,
6196 emit_case_nodes (index
, node
->left
, default_label
, index_type
);
6199 /* We cannot process node->left normally
6200 since we haven't ruled out the numbers less than
6201 this node's value. So handle node->left explicitly. */
6202 do_jump_if_equal (index
,
6205 expand_expr (node
->left
->low
, NULL_RTX
,
6208 label_rtx (node
->left
->code_label
), unsignedp
);
6213 /* Node is a range. These cases are very similar to those for a single
6214 value, except that we do not start by testing whether this node
6215 is the one to branch to. */
6217 if (node
->right
!= 0 && node
->left
!= 0)
6219 /* Node has subtrees on both sides.
6220 If the right-hand subtree is bounded,
6221 test for it first, since we can go straight there.
6222 Otherwise, we need to make a branch in the control structure,
6223 then handle the two subtrees. */
6224 tree test_label
= 0;
6226 if (node_is_bounded (node
->right
, index_type
))
6227 /* Right hand node is fully bounded so we can eliminate any
6228 testing and branch directly to the target code. */
6229 emit_cmp_and_jump_insns (index
,
6232 expand_expr (node
->high
, NULL_RTX
,
6235 GT
, NULL_RTX
, mode
, unsignedp
, 0,
6236 label_rtx (node
->right
->code_label
));
6239 /* Right hand node requires testing.
6240 Branch to a label where we will handle it later. */
6242 test_label
= build_decl (LABEL_DECL
, NULL_TREE
, NULL_TREE
);
6243 emit_cmp_and_jump_insns (index
,
6246 expand_expr (node
->high
, NULL_RTX
,
6249 GT
, NULL_RTX
, mode
, unsignedp
, 0,
6250 label_rtx (test_label
));
6253 /* Value belongs to this node or to the left-hand subtree. */
6255 emit_cmp_and_jump_insns (index
,
6258 expand_expr (node
->low
, NULL_RTX
,
6261 GE
, NULL_RTX
, mode
, unsignedp
, 0,
6262 label_rtx (node
->code_label
));
6264 /* Handle the left-hand subtree. */
6265 emit_case_nodes (index
, node
->left
, default_label
, index_type
);
6267 /* If right node had to be handled later, do that now. */
6271 /* If the left-hand subtree fell through,
6272 don't let it fall into the right-hand subtree. */
6273 emit_jump_if_reachable (default_label
);
6275 expand_label (test_label
);
6276 emit_case_nodes (index
, node
->right
, default_label
, index_type
);
6280 else if (node
->right
!= 0 && node
->left
== 0)
6282 /* Deal with values to the left of this node,
6283 if they are possible. */
6284 if (!node_has_low_bound (node
, index_type
))
6286 emit_cmp_and_jump_insns (index
,
6289 expand_expr (node
->low
, NULL_RTX
,
6292 LT
, NULL_RTX
, mode
, unsignedp
, 0,
6296 /* Value belongs to this node or to the right-hand subtree. */
6298 emit_cmp_and_jump_insns (index
,
6301 expand_expr (node
->high
, NULL_RTX
,
6304 LE
, NULL_RTX
, mode
, unsignedp
, 0,
6305 label_rtx (node
->code_label
));
6307 emit_case_nodes (index
, node
->right
, default_label
, index_type
);
6310 else if (node
->right
== 0 && node
->left
!= 0)
6312 /* Deal with values to the right of this node,
6313 if they are possible. */
6314 if (!node_has_high_bound (node
, index_type
))
6316 emit_cmp_and_jump_insns (index
,
6319 expand_expr (node
->high
, NULL_RTX
,
6322 GT
, NULL_RTX
, mode
, unsignedp
, 0,
6326 /* Value belongs to this node or to the left-hand subtree. */
6328 emit_cmp_and_jump_insns (index
,
6331 expand_expr (node
->low
, NULL_RTX
,
6334 GE
, NULL_RTX
, mode
, unsignedp
, 0,
6335 label_rtx (node
->code_label
));
6337 emit_case_nodes (index
, node
->left
, default_label
, index_type
);
6342 /* Node has no children so we check low and high bounds to remove
6343 redundant tests. Only one of the bounds can exist,
6344 since otherwise this node is bounded--a case tested already. */
6345 int high_bound
= node_has_high_bound (node
, index_type
);
6346 int low_bound
= node_has_low_bound (node
, index_type
);
6348 if (!high_bound
&& low_bound
)
6350 emit_cmp_and_jump_insns (index
,
6353 expand_expr (node
->high
, NULL_RTX
,
6356 GT
, NULL_RTX
, mode
, unsignedp
, 0,
6360 else if (!low_bound
&& high_bound
)
6362 emit_cmp_and_jump_insns (index
,
6365 expand_expr (node
->low
, NULL_RTX
,
6368 LT
, NULL_RTX
, mode
, unsignedp
, 0,
6371 else if (!low_bound
&& !high_bound
)
6373 /* Instead of doing two branches, emit
6374 (index-low) <= (high-low). */
6375 tree new_bound
= fold (build (MINUS_EXPR
, index_type
, node
->high
,
6379 new_index
= expand_binop (mode
, sub_optab
, index
,
6380 convert_modes (mode
, imode
,
6381 expand_expr (node
->low
, NULL_RTX
,
6384 NULL_RTX
, unsignedp
, OPTAB_WIDEN
);
6386 emit_cmp_and_jump_insns (new_index
,
6387 convert_modes (mode
, imode
,
6388 expand_expr (new_bound
, NULL_RTX
,
6391 GT
, NULL_RTX
, mode
, 1, 0,
6395 emit_jump (label_rtx (node
->code_label
));