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5e6908ea | 1 | /* Expands front end tree to back end RTL for GCC |
23a5b65a | 2 | Copyright (C) 1987-2014 Free Software Foundation, Inc. |
28d81abb | 3 | |
1322177d | 4 | This file is part of GCC. |
28d81abb | 5 | |
1322177d LB |
6 | GCC is free software; you can redistribute it and/or modify it under |
7 | the terms of the GNU General Public License as published by the Free | |
9dcd6f09 | 8 | Software Foundation; either version 3, or (at your option) any later |
1322177d | 9 | version. |
28d81abb | 10 | |
1322177d LB |
11 | GCC is distributed in the hope that it will be useful, but WITHOUT ANY |
12 | WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
13 | FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
14 | for more details. | |
28d81abb RK |
15 | |
16 | You should have received a copy of the GNU General Public License | |
9dcd6f09 NC |
17 | along with GCC; see the file COPYING3. If not see |
18 | <http://www.gnu.org/licenses/>. */ | |
28d81abb | 19 | |
28d81abb RK |
20 | /* This file handles the generation of rtl code from tree structure |
21 | above the level of expressions, using subroutines in exp*.c and emit-rtl.c. | |
28d81abb | 22 | The functions whose names start with `expand_' are called by the |
7efcb746 | 23 | expander to generate RTL instructions for various kinds of constructs. */ |
28d81abb RK |
24 | |
25 | #include "config.h" | |
670ee920 | 26 | #include "system.h" |
4977bab6 ZW |
27 | #include "coretypes.h" |
28 | #include "tm.h" | |
ccd043a9 | 29 | |
28d81abb | 30 | #include "rtl.h" |
61158923 | 31 | #include "hard-reg-set.h" |
28d81abb | 32 | #include "tree.h" |
d8a2d370 DN |
33 | #include "varasm.h" |
34 | #include "stor-layout.h" | |
6baf1cc8 | 35 | #include "tm_p.h" |
28d81abb | 36 | #include "flags.h" |
6adb4e3a | 37 | #include "except.h" |
28d81abb | 38 | #include "function.h" |
28d81abb | 39 | #include "insn-config.h" |
28d81abb | 40 | #include "expr.h" |
e78d8e51 | 41 | #include "libfuncs.h" |
28d81abb | 42 | #include "recog.h" |
ca695ac9 | 43 | #include "machmode.h" |
718f9c0f | 44 | #include "diagnostic-core.h" |
d6f4ec51 | 45 | #include "output.h" |
43577e6b | 46 | #include "langhooks.h" |
969d70ca | 47 | #include "predict.h" |
9bb231fd | 48 | #include "optabs.h" |
61f71b34 | 49 | #include "target.h" |
2fb9a547 AM |
50 | #include "pointer-set.h" |
51 | #include "basic-block.h" | |
52 | #include "tree-ssa-alias.h" | |
53 | #include "internal-fn.h" | |
54 | #include "gimple-expr.h" | |
55 | #include "is-a.h" | |
28ed065e | 56 | #include "gimple.h" |
66fd46b6 | 57 | #include "regs.h" |
6ac1b3a4 | 58 | #include "alloc-pool.h" |
4f1e4960 | 59 | #include "pretty-print.h" |
3aa439ed | 60 | #include "params.h" |
7ee2468b | 61 | #include "dumpfile.h" |
9b2b7279 | 62 | #include "builtins.h" |
7a8cba34 | 63 | |
28d81abb RK |
64 | \f |
65 | /* Functions and data structures for expanding case statements. */ | |
66 | ||
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. | |
70 | ||
a6c0a76c SB |
71 | We start with a vector of case nodes sorted in ascending order, and |
72 | the default label as the last element in the vector. Before expanding | |
73 | to RTL, we transform this vector into a list linked via the RIGHT | |
74 | fields in the case_node struct. Nodes with higher case values are | |
75 | later in the list. | |
76 | ||
77 | Switch statements can be output in three forms. A branch table is | |
78 | used if there are more than a few labels and the labels are dense | |
28d81abb RK |
79 | within the range between the smallest and largest case value. If a |
80 | branch table is used, no further manipulations are done with the case | |
81 | node chain. | |
82 | ||
83 | The alternative to the use of a branch table is to generate a series | |
84 | of compare and jump insns. When that is done, we use the LEFT, RIGHT, | |
85 | and PARENT fields to hold a binary tree. Initially the tree is | |
de14fd73 RK |
86 | totally unbalanced, with everything on the right. We balance the tree |
87 | with nodes on the left having lower case values than the parent | |
28d81abb | 88 | and nodes on the right having higher values. We then output the tree |
a6c0a76c SB |
89 | in order. |
90 | ||
91 | For very small, suitable switch statements, we can generate a series | |
92 | of simple bit test and branches instead. */ | |
28d81abb | 93 | |
6ac1b3a4 | 94 | struct case_node |
28d81abb RK |
95 | { |
96 | struct case_node *left; /* Left son in binary tree */ | |
97 | struct case_node *right; /* Right son in binary tree; also node chain */ | |
98 | struct case_node *parent; /* Parent of node in binary tree */ | |
99 | tree low; /* Lowest index value for this label */ | |
100 | tree high; /* Highest index value for this label */ | |
101 | tree code_label; /* Label to jump to when node matches */ | |
a4da41e1 ER |
102 | int prob; /* Probability of taking this case. */ |
103 | /* Probability of reaching subtree rooted at this node */ | |
104 | int subtree_prob; | |
28d81abb RK |
105 | }; |
106 | ||
107 | typedef struct case_node case_node; | |
108 | typedef struct case_node *case_node_ptr; | |
109 | ||
a4da41e1 | 110 | extern basic_block label_to_block_fn (struct function *, tree); |
28d81abb | 111 | \f |
1c384bf1 RH |
112 | static bool check_unique_operand_names (tree, tree, tree); |
113 | static char *resolve_operand_name_1 (char *, tree, tree, tree); | |
46c5ad27 AJ |
114 | static void balance_case_nodes (case_node_ptr *, case_node_ptr); |
115 | static int node_has_low_bound (case_node_ptr, tree); | |
116 | static int node_has_high_bound (case_node_ptr, tree); | |
117 | static int node_is_bounded (case_node_ptr, tree); | |
a4da41e1 | 118 | static void emit_case_nodes (rtx, case_node_ptr, rtx, int, tree); |
28d81abb RK |
119 | \f |
120 | /* Return the rtx-label that corresponds to a LABEL_DECL, | |
121 | creating it if necessary. */ | |
122 | ||
123 | rtx | |
46c5ad27 | 124 | label_rtx (tree label) |
28d81abb | 125 | { |
41374e13 | 126 | gcc_assert (TREE_CODE (label) == LABEL_DECL); |
28d81abb | 127 | |
19e7881c | 128 | if (!DECL_RTL_SET_P (label)) |
6de9cd9a DN |
129 | { |
130 | rtx r = gen_label_rtx (); | |
131 | SET_DECL_RTL (label, r); | |
132 | if (FORCED_LABEL (label) || DECL_NONLOCAL (label)) | |
133 | LABEL_PRESERVE_P (r) = 1; | |
134 | } | |
28d81abb | 135 | |
19e7881c | 136 | return DECL_RTL (label); |
28d81abb RK |
137 | } |
138 | ||
046e4e36 ZW |
139 | /* As above, but also put it on the forced-reference list of the |
140 | function that contains it. */ | |
141 | rtx | |
46c5ad27 | 142 | force_label_rtx (tree label) |
046e4e36 ZW |
143 | { |
144 | rtx ref = label_rtx (label); | |
145 | tree function = decl_function_context (label); | |
046e4e36 | 146 | |
41374e13 | 147 | gcc_assert (function); |
046e4e36 | 148 | |
bd60bab2 | 149 | forced_labels = gen_rtx_EXPR_LIST (VOIDmode, ref, forced_labels); |
046e4e36 ZW |
150 | return ref; |
151 | } | |
19e7881c | 152 | |
28d81abb RK |
153 | /* Add an unconditional jump to LABEL as the next sequential instruction. */ |
154 | ||
155 | void | |
46c5ad27 | 156 | emit_jump (rtx label) |
28d81abb RK |
157 | { |
158 | do_pending_stack_adjust (); | |
159 | emit_jump_insn (gen_jump (label)); | |
160 | emit_barrier (); | |
161 | } | |
28d81abb RK |
162 | \f |
163 | /* Handle goto statements and the labels that they can go to. */ | |
164 | ||
165 | /* Specify the location in the RTL code of a label LABEL, | |
166 | which is a LABEL_DECL tree node. | |
167 | ||
168 | This is used for the kind of label that the user can jump to with a | |
169 | goto statement, and for alternatives of a switch or case statement. | |
170 | RTL labels generated for loops and conditionals don't go through here; | |
171 | they are generated directly at the RTL level, by other functions below. | |
172 | ||
173 | Note that this has nothing to do with defining label *names*. | |
174 | Languages vary in how they do that and what that even means. */ | |
175 | ||
176 | void | |
46c5ad27 | 177 | expand_label (tree label) |
28d81abb | 178 | { |
6de9cd9a | 179 | rtx label_r = label_rtx (label); |
28d81abb RK |
180 | |
181 | do_pending_stack_adjust (); | |
6de9cd9a | 182 | emit_label (label_r); |
28d81abb RK |
183 | if (DECL_NAME (label)) |
184 | LABEL_NAME (DECL_RTL (label)) = IDENTIFIER_POINTER (DECL_NAME (label)); | |
185 | ||
6de9cd9a DN |
186 | if (DECL_NONLOCAL (label)) |
187 | { | |
e90d1568 | 188 | expand_builtin_setjmp_receiver (NULL); |
6de9cd9a DN |
189 | nonlocal_goto_handler_labels |
190 | = gen_rtx_EXPR_LIST (VOIDmode, label_r, | |
191 | nonlocal_goto_handler_labels); | |
192 | } | |
193 | ||
194 | if (FORCED_LABEL (label)) | |
195 | forced_labels = gen_rtx_EXPR_LIST (VOIDmode, label_r, forced_labels); | |
caf93cb0 | 196 | |
6de9cd9a DN |
197 | if (DECL_NONLOCAL (label) || FORCED_LABEL (label)) |
198 | maybe_set_first_label_num (label_r); | |
28d81abb | 199 | } |
2a230e9d | 200 | \f |
40b18c0a MM |
201 | /* Parse the output constraint pointed to by *CONSTRAINT_P. It is the |
202 | OPERAND_NUMth output operand, indexed from zero. There are NINPUTS | |
203 | inputs and NOUTPUTS outputs to this extended-asm. Upon return, | |
204 | *ALLOWS_MEM will be TRUE iff the constraint allows the use of a | |
205 | memory operand. Similarly, *ALLOWS_REG will be TRUE iff the | |
206 | constraint allows the use of a register operand. And, *IS_INOUT | |
207 | will be true if the operand is read-write, i.e., if it is used as | |
208 | an input as well as an output. If *CONSTRAINT_P is not in | |
209 | canonical form, it will be made canonical. (Note that `+' will be | |
14b493d6 | 210 | replaced with `=' as part of this process.) |
40b18c0a MM |
211 | |
212 | Returns TRUE if all went well; FALSE if an error occurred. */ | |
213 | ||
214 | bool | |
46c5ad27 AJ |
215 | parse_output_constraint (const char **constraint_p, int operand_num, |
216 | int ninputs, int noutputs, bool *allows_mem, | |
217 | bool *allows_reg, bool *is_inout) | |
40b18c0a MM |
218 | { |
219 | const char *constraint = *constraint_p; | |
220 | const char *p; | |
221 | ||
222 | /* Assume the constraint doesn't allow the use of either a register | |
223 | or memory. */ | |
224 | *allows_mem = false; | |
225 | *allows_reg = false; | |
226 | ||
227 | /* Allow the `=' or `+' to not be at the beginning of the string, | |
228 | since it wasn't explicitly documented that way, and there is a | |
229 | large body of code that puts it last. Swap the character to | |
230 | the front, so as not to uglify any place else. */ | |
231 | p = strchr (constraint, '='); | |
232 | if (!p) | |
233 | p = strchr (constraint, '+'); | |
234 | ||
235 | /* If the string doesn't contain an `=', issue an error | |
236 | message. */ | |
237 | if (!p) | |
238 | { | |
971801ff | 239 | error ("output operand constraint lacks %<=%>"); |
40b18c0a MM |
240 | return false; |
241 | } | |
242 | ||
243 | /* If the constraint begins with `+', then the operand is both read | |
244 | from and written to. */ | |
245 | *is_inout = (*p == '+'); | |
246 | ||
40b18c0a | 247 | /* Canonicalize the output constraint so that it begins with `='. */ |
372d72d9 | 248 | if (p != constraint || *is_inout) |
40b18c0a MM |
249 | { |
250 | char *buf; | |
251 | size_t c_len = strlen (constraint); | |
252 | ||
253 | if (p != constraint) | |
d4ee4d25 | 254 | warning (0, "output constraint %qc for operand %d " |
971801ff | 255 | "is not at the beginning", |
40b18c0a MM |
256 | *p, operand_num); |
257 | ||
258 | /* Make a copy of the constraint. */ | |
1634b18f | 259 | buf = XALLOCAVEC (char, c_len + 1); |
40b18c0a MM |
260 | strcpy (buf, constraint); |
261 | /* Swap the first character and the `=' or `+'. */ | |
262 | buf[p - constraint] = buf[0]; | |
263 | /* Make sure the first character is an `='. (Until we do this, | |
264 | it might be a `+'.) */ | |
265 | buf[0] = '='; | |
266 | /* Replace the constraint with the canonicalized string. */ | |
267 | *constraint_p = ggc_alloc_string (buf, c_len); | |
268 | constraint = *constraint_p; | |
269 | } | |
270 | ||
271 | /* Loop through the constraint string. */ | |
97488870 | 272 | for (p = constraint + 1; *p; p += CONSTRAINT_LEN (*p, p)) |
40b18c0a MM |
273 | switch (*p) |
274 | { | |
275 | case '+': | |
276 | case '=': | |
971801ff JM |
277 | error ("operand constraint contains incorrectly positioned " |
278 | "%<+%> or %<=%>"); | |
40b18c0a | 279 | return false; |
786de7eb | 280 | |
40b18c0a MM |
281 | case '%': |
282 | if (operand_num + 1 == ninputs + noutputs) | |
283 | { | |
971801ff | 284 | error ("%<%%%> constraint used with last operand"); |
40b18c0a MM |
285 | return false; |
286 | } | |
287 | break; | |
288 | ||
a4edaf83 | 289 | case 'V': case TARGET_MEM_CONSTRAINT: case 'o': |
40b18c0a MM |
290 | *allows_mem = true; |
291 | break; | |
292 | ||
293 | case '?': case '!': case '*': case '&': case '#': | |
294 | case 'E': case 'F': case 'G': case 'H': | |
295 | case 's': case 'i': case 'n': | |
296 | case 'I': case 'J': case 'K': case 'L': case 'M': | |
297 | case 'N': case 'O': case 'P': case ',': | |
298 | break; | |
299 | ||
300 | case '0': case '1': case '2': case '3': case '4': | |
301 | case '5': case '6': case '7': case '8': case '9': | |
84b72302 | 302 | case '[': |
40b18c0a MM |
303 | error ("matching constraint not valid in output operand"); |
304 | return false; | |
305 | ||
306 | case '<': case '>': | |
307 | /* ??? Before flow, auto inc/dec insns are not supposed to exist, | |
308 | excepting those that expand_call created. So match memory | |
309 | and hope. */ | |
310 | *allows_mem = true; | |
311 | break; | |
312 | ||
313 | case 'g': case 'X': | |
314 | *allows_reg = true; | |
315 | *allows_mem = true; | |
316 | break; | |
786de7eb | 317 | |
40b18c0a MM |
318 | case 'p': case 'r': |
319 | *allows_reg = true; | |
320 | break; | |
321 | ||
322 | default: | |
323 | if (!ISALPHA (*p)) | |
324 | break; | |
97488870 | 325 | if (REG_CLASS_FROM_CONSTRAINT (*p, p) != NO_REGS) |
40b18c0a | 326 | *allows_reg = true; |
97488870 R |
327 | #ifdef EXTRA_CONSTRAINT_STR |
328 | else if (EXTRA_ADDRESS_CONSTRAINT (*p, p)) | |
ccfc6cc8 | 329 | *allows_reg = true; |
97488870 | 330 | else if (EXTRA_MEMORY_CONSTRAINT (*p, p)) |
ccfc6cc8 | 331 | *allows_mem = true; |
40b18c0a MM |
332 | else |
333 | { | |
334 | /* Otherwise we can't assume anything about the nature of | |
335 | the constraint except that it isn't purely registers. | |
336 | Treat it like "g" and hope for the best. */ | |
337 | *allows_reg = true; | |
338 | *allows_mem = true; | |
339 | } | |
340 | #endif | |
341 | break; | |
342 | } | |
343 | ||
344 | return true; | |
345 | } | |
346 | ||
6be2e1f8 RH |
347 | /* Similar, but for input constraints. */ |
348 | ||
1456deaf | 349 | bool |
46c5ad27 AJ |
350 | parse_input_constraint (const char **constraint_p, int input_num, |
351 | int ninputs, int noutputs, int ninout, | |
352 | const char * const * constraints, | |
353 | bool *allows_mem, bool *allows_reg) | |
6be2e1f8 RH |
354 | { |
355 | const char *constraint = *constraint_p; | |
356 | const char *orig_constraint = constraint; | |
357 | size_t c_len = strlen (constraint); | |
358 | size_t j; | |
f3da0ead | 359 | bool saw_match = false; |
6be2e1f8 RH |
360 | |
361 | /* Assume the constraint doesn't allow the use of either | |
362 | a register or memory. */ | |
363 | *allows_mem = false; | |
364 | *allows_reg = false; | |
365 | ||
366 | /* Make sure constraint has neither `=', `+', nor '&'. */ | |
367 | ||
97488870 | 368 | for (j = 0; j < c_len; j += CONSTRAINT_LEN (constraint[j], constraint+j)) |
6be2e1f8 RH |
369 | switch (constraint[j]) |
370 | { | |
371 | case '+': case '=': case '&': | |
372 | if (constraint == orig_constraint) | |
373 | { | |
971801ff | 374 | error ("input operand constraint contains %qc", constraint[j]); |
6be2e1f8 RH |
375 | return false; |
376 | } | |
377 | break; | |
378 | ||
379 | case '%': | |
380 | if (constraint == orig_constraint | |
381 | && input_num + 1 == ninputs - ninout) | |
382 | { | |
971801ff | 383 | error ("%<%%%> constraint used with last operand"); |
6be2e1f8 RH |
384 | return false; |
385 | } | |
386 | break; | |
387 | ||
a4edaf83 | 388 | case 'V': case TARGET_MEM_CONSTRAINT: case 'o': |
6be2e1f8 RH |
389 | *allows_mem = true; |
390 | break; | |
391 | ||
392 | case '<': case '>': | |
393 | case '?': case '!': case '*': case '#': | |
394 | case 'E': case 'F': case 'G': case 'H': | |
395 | case 's': case 'i': case 'n': | |
396 | case 'I': case 'J': case 'K': case 'L': case 'M': | |
397 | case 'N': case 'O': case 'P': case ',': | |
398 | break; | |
399 | ||
400 | /* Whether or not a numeric constraint allows a register is | |
401 | decided by the matching constraint, and so there is no need | |
402 | to do anything special with them. We must handle them in | |
403 | the default case, so that we don't unnecessarily force | |
404 | operands to memory. */ | |
405 | case '0': case '1': case '2': case '3': case '4': | |
406 | case '5': case '6': case '7': case '8': case '9': | |
407 | { | |
408 | char *end; | |
409 | unsigned long match; | |
410 | ||
f3da0ead JM |
411 | saw_match = true; |
412 | ||
6be2e1f8 RH |
413 | match = strtoul (constraint + j, &end, 10); |
414 | if (match >= (unsigned long) noutputs) | |
415 | { | |
416 | error ("matching constraint references invalid operand number"); | |
417 | return false; | |
418 | } | |
419 | ||
420 | /* Try and find the real constraint for this dup. Only do this | |
421 | if the matching constraint is the only alternative. */ | |
422 | if (*end == '\0' | |
423 | && (j == 0 || (j == 1 && constraint[0] == '%'))) | |
424 | { | |
425 | constraint = constraints[match]; | |
426 | *constraint_p = constraint; | |
427 | c_len = strlen (constraint); | |
428 | j = 0; | |
97488870 R |
429 | /* ??? At the end of the loop, we will skip the first part of |
430 | the matched constraint. This assumes not only that the | |
431 | other constraint is an output constraint, but also that | |
432 | the '=' or '+' come first. */ | |
6be2e1f8 RH |
433 | break; |
434 | } | |
435 | else | |
436 | j = end - constraint; | |
97488870 R |
437 | /* Anticipate increment at end of loop. */ |
438 | j--; | |
6be2e1f8 RH |
439 | } |
440 | /* Fall through. */ | |
441 | ||
442 | case 'p': case 'r': | |
443 | *allows_reg = true; | |
444 | break; | |
445 | ||
446 | case 'g': case 'X': | |
447 | *allows_reg = true; | |
448 | *allows_mem = true; | |
449 | break; | |
450 | ||
451 | default: | |
452 | if (! ISALPHA (constraint[j])) | |
453 | { | |
971801ff | 454 | error ("invalid punctuation %qc in constraint", constraint[j]); |
6be2e1f8 RH |
455 | return false; |
456 | } | |
97488870 R |
457 | if (REG_CLASS_FROM_CONSTRAINT (constraint[j], constraint + j) |
458 | != NO_REGS) | |
6be2e1f8 | 459 | *allows_reg = true; |
97488870 R |
460 | #ifdef EXTRA_CONSTRAINT_STR |
461 | else if (EXTRA_ADDRESS_CONSTRAINT (constraint[j], constraint + j)) | |
ccfc6cc8 | 462 | *allows_reg = true; |
97488870 | 463 | else if (EXTRA_MEMORY_CONSTRAINT (constraint[j], constraint + j)) |
ccfc6cc8 | 464 | *allows_mem = true; |
6be2e1f8 RH |
465 | else |
466 | { | |
467 | /* Otherwise we can't assume anything about the nature of | |
468 | the constraint except that it isn't purely registers. | |
469 | Treat it like "g" and hope for the best. */ | |
470 | *allows_reg = true; | |
471 | *allows_mem = true; | |
472 | } | |
473 | #endif | |
474 | break; | |
475 | } | |
476 | ||
f3da0ead | 477 | if (saw_match && !*allows_reg) |
d4ee4d25 | 478 | warning (0, "matching constraint does not allow a register"); |
f3da0ead | 479 | |
6be2e1f8 RH |
480 | return true; |
481 | } | |
482 | ||
91b4415a R |
483 | /* Return DECL iff there's an overlap between *REGS and DECL, where DECL |
484 | can be an asm-declared register. Called via walk_tree. */ | |
acb5d088 | 485 | |
91b4415a R |
486 | static tree |
487 | decl_overlaps_hard_reg_set_p (tree *declp, int *walk_subtrees ATTRIBUTE_UNUSED, | |
488 | void *data) | |
acb5d088 | 489 | { |
91b4415a | 490 | tree decl = *declp; |
1634b18f | 491 | const HARD_REG_SET *const regs = (const HARD_REG_SET *) data; |
91b4415a | 492 | |
3f2de3dc | 493 | if (TREE_CODE (decl) == VAR_DECL) |
acb5d088 | 494 | { |
3f2de3dc | 495 | if (DECL_HARD_REGISTER (decl) |
91b4415a R |
496 | && REG_P (DECL_RTL (decl)) |
497 | && REGNO (DECL_RTL (decl)) < FIRST_PSEUDO_REGISTER) | |
498 | { | |
499 | rtx reg = DECL_RTL (decl); | |
09e18274 RS |
500 | |
501 | if (overlaps_hard_reg_set_p (*regs, GET_MODE (reg), REGNO (reg))) | |
502 | return decl; | |
91b4415a R |
503 | } |
504 | walk_subtrees = 0; | |
61158923 | 505 | } |
3f2de3dc | 506 | else if (TYPE_P (decl) || TREE_CODE (decl) == PARM_DECL) |
91b4415a R |
507 | walk_subtrees = 0; |
508 | return NULL_TREE; | |
61158923 HPN |
509 | } |
510 | ||
91b4415a R |
511 | /* If there is an overlap between *REGS and DECL, return the first overlap |
512 | found. */ | |
513 | tree | |
514 | tree_overlaps_hard_reg_set (tree decl, HARD_REG_SET *regs) | |
515 | { | |
516 | return walk_tree (&decl, decl_overlaps_hard_reg_set_p, regs, NULL); | |
517 | } | |
61158923 | 518 | |
84b72302 RH |
519 | |
520 | /* A subroutine of expand_asm_operands. Check that all operand names | |
521 | are unique. Return true if so. We rely on the fact that these names | |
522 | are identifiers, and so have been canonicalized by get_identifier, | |
523 | so all we need are pointer comparisons. */ | |
524 | ||
525 | static bool | |
1c384bf1 | 526 | check_unique_operand_names (tree outputs, tree inputs, tree labels) |
84b72302 | 527 | { |
36363ebb | 528 | tree i, j, i_name = NULL_TREE; |
84b72302 RH |
529 | |
530 | for (i = outputs; i ; i = TREE_CHAIN (i)) | |
531 | { | |
36363ebb | 532 | i_name = TREE_PURPOSE (TREE_PURPOSE (i)); |
84b72302 RH |
533 | if (! i_name) |
534 | continue; | |
535 | ||
536 | for (j = TREE_CHAIN (i); j ; j = TREE_CHAIN (j)) | |
fc552851 | 537 | if (simple_cst_equal (i_name, TREE_PURPOSE (TREE_PURPOSE (j)))) |
84b72302 RH |
538 | goto failure; |
539 | } | |
540 | ||
541 | for (i = inputs; i ; i = TREE_CHAIN (i)) | |
542 | { | |
36363ebb | 543 | i_name = TREE_PURPOSE (TREE_PURPOSE (i)); |
84b72302 RH |
544 | if (! i_name) |
545 | continue; | |
546 | ||
547 | for (j = TREE_CHAIN (i); j ; j = TREE_CHAIN (j)) | |
fc552851 | 548 | if (simple_cst_equal (i_name, TREE_PURPOSE (TREE_PURPOSE (j)))) |
84b72302 RH |
549 | goto failure; |
550 | for (j = outputs; j ; j = TREE_CHAIN (j)) | |
fc552851 | 551 | if (simple_cst_equal (i_name, TREE_PURPOSE (TREE_PURPOSE (j)))) |
84b72302 RH |
552 | goto failure; |
553 | } | |
554 | ||
1c384bf1 RH |
555 | for (i = labels; i ; i = TREE_CHAIN (i)) |
556 | { | |
36363ebb | 557 | i_name = TREE_PURPOSE (i); |
1c384bf1 RH |
558 | if (! i_name) |
559 | continue; | |
560 | ||
561 | for (j = TREE_CHAIN (i); j ; j = TREE_CHAIN (j)) | |
562 | if (simple_cst_equal (i_name, TREE_PURPOSE (j))) | |
563 | goto failure; | |
564 | for (j = inputs; j ; j = TREE_CHAIN (j)) | |
565 | if (simple_cst_equal (i_name, TREE_PURPOSE (TREE_PURPOSE (j)))) | |
566 | goto failure; | |
567 | } | |
568 | ||
84b72302 RH |
569 | return true; |
570 | ||
571 | failure: | |
36363ebb | 572 | error ("duplicate asm operand name %qs", TREE_STRING_POINTER (i_name)); |
84b72302 RH |
573 | return false; |
574 | } | |
575 | ||
576 | /* A subroutine of expand_asm_operands. Resolve the names of the operands | |
577 | in *POUTPUTS and *PINPUTS to numbers, and replace the name expansions in | |
578 | STRING and in the constraints to those numbers. */ | |
579 | ||
7dc8b126 | 580 | tree |
1c384bf1 | 581 | resolve_asm_operand_names (tree string, tree outputs, tree inputs, tree labels) |
84b72302 | 582 | { |
7dc8b126 | 583 | char *buffer; |
84b72302 | 584 | char *p; |
40209195 | 585 | const char *c; |
84b72302 RH |
586 | tree t; |
587 | ||
1c384bf1 | 588 | check_unique_operand_names (outputs, inputs, labels); |
1456deaf | 589 | |
7dc8b126 JM |
590 | /* Substitute [<name>] in input constraint strings. There should be no |
591 | named operands in output constraints. */ | |
592 | for (t = inputs; t ; t = TREE_CHAIN (t)) | |
593 | { | |
40209195 | 594 | c = TREE_STRING_POINTER (TREE_VALUE (TREE_PURPOSE (t))); |
7dc8b126 JM |
595 | if (strchr (c, '[') != NULL) |
596 | { | |
597 | p = buffer = xstrdup (c); | |
598 | while ((p = strchr (p, '[')) != NULL) | |
1c384bf1 | 599 | p = resolve_operand_name_1 (p, outputs, inputs, NULL); |
7dc8b126 JM |
600 | TREE_VALUE (TREE_PURPOSE (t)) |
601 | = build_string (strlen (buffer), buffer); | |
602 | free (buffer); | |
603 | } | |
604 | } | |
605 | ||
40209195 JM |
606 | /* Now check for any needed substitutions in the template. */ |
607 | c = TREE_STRING_POINTER (string); | |
608 | while ((c = strchr (c, '%')) != NULL) | |
84b72302 | 609 | { |
40209195 JM |
610 | if (c[1] == '[') |
611 | break; | |
612 | else if (ISALPHA (c[1]) && c[2] == '[') | |
613 | break; | |
7abcb63a RH |
614 | else |
615 | { | |
d34b4f64 | 616 | c += 1 + (c[1] == '%'); |
7abcb63a RH |
617 | continue; |
618 | } | |
84b72302 RH |
619 | } |
620 | ||
40209195 JM |
621 | if (c) |
622 | { | |
623 | /* OK, we need to make a copy so we can perform the substitutions. | |
624 | Assume that we will not need extra space--we get to remove '[' | |
625 | and ']', which means we cannot have a problem until we have more | |
626 | than 999 operands. */ | |
627 | buffer = xstrdup (TREE_STRING_POINTER (string)); | |
628 | p = buffer + (c - TREE_STRING_POINTER (string)); | |
caf93cb0 | 629 | |
40209195 JM |
630 | while ((p = strchr (p, '%')) != NULL) |
631 | { | |
632 | if (p[1] == '[') | |
633 | p += 1; | |
634 | else if (ISALPHA (p[1]) && p[2] == '[') | |
635 | p += 2; | |
636 | else | |
637 | { | |
d34b4f64 | 638 | p += 1 + (p[1] == '%'); |
40209195 JM |
639 | continue; |
640 | } | |
641 | ||
1c384bf1 | 642 | p = resolve_operand_name_1 (p, outputs, inputs, labels); |
40209195 JM |
643 | } |
644 | ||
645 | string = build_string (strlen (buffer), buffer); | |
646 | free (buffer); | |
647 | } | |
84b72302 | 648 | |
84b72302 RH |
649 | return string; |
650 | } | |
651 | ||
652 | /* A subroutine of resolve_operand_names. P points to the '[' for a | |
653 | potential named operand of the form [<name>]. In place, replace | |
786de7eb | 654 | the name and brackets with a number. Return a pointer to the |
84b72302 RH |
655 | balance of the string after substitution. */ |
656 | ||
657 | static char * | |
1c384bf1 | 658 | resolve_operand_name_1 (char *p, tree outputs, tree inputs, tree labels) |
84b72302 RH |
659 | { |
660 | char *q; | |
661 | int op; | |
662 | tree t; | |
84b72302 RH |
663 | |
664 | /* Collect the operand name. */ | |
1c384bf1 | 665 | q = strchr (++p, ']'); |
84b72302 RH |
666 | if (!q) |
667 | { | |
668 | error ("missing close brace for named operand"); | |
669 | return strchr (p, '\0'); | |
670 | } | |
1c384bf1 | 671 | *q = '\0'; |
84b72302 RH |
672 | |
673 | /* Resolve the name to a number. */ | |
674 | for (op = 0, t = outputs; t ; t = TREE_CHAIN (t), op++) | |
675 | { | |
fc552851 | 676 | tree name = TREE_PURPOSE (TREE_PURPOSE (t)); |
1c384bf1 RH |
677 | if (name && strcmp (TREE_STRING_POINTER (name), p) == 0) |
678 | goto found; | |
84b72302 RH |
679 | } |
680 | for (t = inputs; t ; t = TREE_CHAIN (t), op++) | |
681 | { | |
fc552851 | 682 | tree name = TREE_PURPOSE (TREE_PURPOSE (t)); |
1c384bf1 RH |
683 | if (name && strcmp (TREE_STRING_POINTER (name), p) == 0) |
684 | goto found; | |
685 | } | |
686 | for (t = labels; t ; t = TREE_CHAIN (t), op++) | |
687 | { | |
688 | tree name = TREE_PURPOSE (t); | |
689 | if (name && strcmp (TREE_STRING_POINTER (name), p) == 0) | |
690 | goto found; | |
84b72302 RH |
691 | } |
692 | ||
1c384bf1 | 693 | error ("undefined named operand %qs", identifier_to_locale (p)); |
84b72302 | 694 | op = 0; |
84b72302 | 695 | |
1c384bf1 | 696 | found: |
84b72302 RH |
697 | /* Replace the name with the number. Unfortunately, not all libraries |
698 | get the return value of sprintf correct, so search for the end of the | |
699 | generated string by hand. */ | |
1c384bf1 | 700 | sprintf (--p, "%d", op); |
84b72302 RH |
701 | p = strchr (p, '\0'); |
702 | ||
703 | /* Verify the no extra buffer space assumption. */ | |
41374e13 | 704 | gcc_assert (p <= q); |
84b72302 RH |
705 | |
706 | /* Shift the rest of the buffer down to fill the gap. */ | |
707 | memmove (p, q + 1, strlen (q + 1) + 1); | |
708 | ||
709 | return p; | |
710 | } | |
28d81abb | 711 | \f |
28d81abb | 712 | |
6e3077c6 EB |
713 | /* Generate RTL to return directly from the current function. |
714 | (That is, we bypass any return value.) */ | |
715 | ||
716 | void | |
717 | expand_naked_return (void) | |
718 | { | |
ac45df5d | 719 | rtx end_label; |
6e3077c6 EB |
720 | |
721 | clear_pending_stack_adjust (); | |
722 | do_pending_stack_adjust (); | |
6e3077c6 | 723 | |
ac45df5d | 724 | end_label = naked_return_label; |
6e3077c6 EB |
725 | if (end_label == 0) |
726 | end_label = naked_return_label = gen_label_rtx (); | |
ac45df5d RH |
727 | |
728 | emit_jump (end_label); | |
6e3077c6 EB |
729 | } |
730 | ||
a4da41e1 ER |
731 | /* Generate code to jump to LABEL if OP0 and OP1 are equal in mode MODE. PROB |
732 | is the probability of jumping to LABEL. */ | |
9a1b6b7a SB |
733 | static void |
734 | do_jump_if_equal (enum machine_mode mode, rtx op0, rtx op1, rtx label, | |
a4da41e1 | 735 | int unsignedp, int prob) |
9a1b6b7a | 736 | { |
a4da41e1 | 737 | gcc_assert (prob <= REG_BR_PROB_BASE); |
9a1b6b7a | 738 | do_compare_rtx_and_jump (op0, op1, EQ, unsignedp, mode, |
a4da41e1 | 739 | NULL_RTX, NULL_RTX, label, prob); |
9a1b6b7a | 740 | } |
28d81abb | 741 | \f |
7efcb746 PB |
742 | /* Do the insertion of a case label into case_list. The labels are |
743 | fed to us in descending order from the sorted vector of case labels used | |
a6c0a76c | 744 | in the tree part of the middle end. So the list we construct is |
a4da41e1 ER |
745 | sorted in ascending order. |
746 | ||
747 | LABEL is the case label to be inserted. LOW and HIGH are the bounds | |
748 | against which the index is compared to jump to LABEL and PROB is the | |
749 | estimated probability LABEL is reached from the switch statement. */ | |
57641239 | 750 | |
eb172681 | 751 | static struct case_node * |
9a1b6b7a | 752 | add_case_node (struct case_node *head, tree low, tree high, |
a4da41e1 | 753 | tree label, int prob, alloc_pool case_node_pool) |
57641239 | 754 | { |
a6c0a76c | 755 | struct case_node *r; |
57641239 | 756 | |
0cd2402d | 757 | gcc_checking_assert (low); |
9a1b6b7a | 758 | gcc_checking_assert (high && (TREE_TYPE (low) == TREE_TYPE (high))); |
56cb9733 | 759 | |
9a1b6b7a | 760 | /* Add this label to the chain. */ |
6ac1b3a4 | 761 | r = (struct case_node *) pool_alloc (case_node_pool); |
9a1b6b7a SB |
762 | r->low = low; |
763 | r->high = high; | |
57641239 | 764 | r->code_label = label; |
a6c0a76c | 765 | r->parent = r->left = NULL; |
a4da41e1 ER |
766 | r->prob = prob; |
767 | r->subtree_prob = prob; | |
7efcb746 PB |
768 | r->right = head; |
769 | return r; | |
28d81abb | 770 | } |
28d81abb | 771 | \f |
04a40cb9 SB |
772 | /* Dump ROOT, a list or tree of case nodes, to file. */ |
773 | ||
774 | static void | |
775 | dump_case_nodes (FILE *f, struct case_node *root, | |
776 | int indent_step, int indent_level) | |
777 | { | |
04a40cb9 SB |
778 | if (root == 0) |
779 | return; | |
780 | indent_level++; | |
781 | ||
782 | dump_case_nodes (f, root->left, indent_step, indent_level); | |
783 | ||
04a40cb9 | 784 | fputs (";; ", f); |
3ce6c715 SB |
785 | fprintf (f, "%*s", indent_step * indent_level, ""); |
786 | print_dec (root->low, f, TYPE_SIGN (TREE_TYPE (root->low))); | |
787 | if (!tree_int_cst_equal (root->low, root->high)) | |
788 | { | |
789 | fprintf (f, " ... "); | |
790 | print_dec (root->high, f, TYPE_SIGN (TREE_TYPE (root->high))); | |
791 | } | |
04a40cb9 SB |
792 | fputs ("\n", f); |
793 | ||
794 | dump_case_nodes (f, root->right, indent_step, indent_level); | |
795 | } | |
796 | \f | |
41cbdcd0 KH |
797 | #ifndef HAVE_casesi |
798 | #define HAVE_casesi 0 | |
799 | #endif | |
800 | ||
801 | #ifndef HAVE_tablejump | |
802 | #define HAVE_tablejump 0 | |
803 | #endif | |
804 | ||
3aa439ed MM |
805 | /* Return the smallest number of different values for which it is best to use a |
806 | jump-table instead of a tree of conditional branches. */ | |
807 | ||
808 | static unsigned int | |
809 | case_values_threshold (void) | |
810 | { | |
811 | unsigned int threshold = PARAM_VALUE (PARAM_CASE_VALUES_THRESHOLD); | |
812 | ||
813 | if (threshold == 0) | |
814 | threshold = targetm.case_values_threshold (); | |
815 | ||
816 | return threshold; | |
817 | } | |
818 | ||
04a40cb9 SB |
819 | /* Return true if a switch should be expanded as a decision tree. |
820 | RANGE is the difference between highest and lowest case. | |
821 | UNIQ is number of unique case node targets, not counting the default case. | |
822 | COUNT is the number of comparisons needed, not counting the default case. */ | |
28d81abb | 823 | |
04a40cb9 SB |
824 | static bool |
825 | expand_switch_as_decision_tree_p (tree range, | |
826 | unsigned int uniq ATTRIBUTE_UNUSED, | |
827 | unsigned int count) | |
28d81abb | 828 | { |
04a40cb9 SB |
829 | int max_ratio; |
830 | ||
831 | /* If neither casesi or tablejump is available, or flag_jump_tables | |
832 | over-ruled us, we really have no choice. */ | |
833 | if (!HAVE_casesi && !HAVE_tablejump) | |
834 | return true; | |
835 | if (!flag_jump_tables) | |
836 | return true; | |
f5c2caca JJ |
837 | #ifndef ASM_OUTPUT_ADDR_DIFF_ELT |
838 | if (flag_pic) | |
839 | return true; | |
840 | #endif | |
04a40cb9 SB |
841 | |
842 | /* If the switch is relatively small such that the cost of one | |
843 | indirect jump on the target are higher than the cost of a | |
844 | decision tree, go with the decision tree. | |
845 | ||
846 | If range of values is much bigger than number of values, | |
847 | or if it is too large to represent in a HOST_WIDE_INT, | |
848 | make a sequence of conditional branches instead of a dispatch. | |
849 | ||
850 | The definition of "much bigger" depends on whether we are | |
851 | optimizing for size or for speed. If the former, the maximum | |
852 | ratio range/count = 3, because this was found to be the optimal | |
853 | ratio for size on i686-pc-linux-gnu, see PR11823. The ratio | |
854 | 10 is much older, and was probably selected after an extensive | |
855 | benchmarking investigation on numerous platforms. Or maybe it | |
856 | just made sense to someone at some point in the history of GCC, | |
857 | who knows... */ | |
858 | max_ratio = optimize_insn_for_size_p () ? 3 : 10; | |
859 | if (count < case_values_threshold () | |
cc269bb6 | 860 | || ! tree_fits_uhwi_p (range) |
04a40cb9 SB |
861 | || compare_tree_int (range, max_ratio * count) > 0) |
862 | return true; | |
ca695ac9 | 863 | |
04a40cb9 SB |
864 | return false; |
865 | } | |
7efcb746 | 866 | |
04a40cb9 SB |
867 | /* Generate a decision tree, switching on INDEX_EXPR and jumping to |
868 | one of the labels in CASE_LIST or to the DEFAULT_LABEL. | |
a4da41e1 ER |
869 | DEFAULT_PROB is the estimated probability that it jumps to |
870 | DEFAULT_LABEL. | |
04a40cb9 SB |
871 | |
872 | We generate a binary decision tree to select the appropriate target | |
873 | code. This is done as follows: | |
7efcb746 | 874 | |
04a40cb9 SB |
875 | If the index is a short or char that we do not have |
876 | an insn to handle comparisons directly, convert it to | |
877 | a full integer now, rather than letting each comparison | |
878 | generate the conversion. | |
879 | ||
880 | Load the index into a register. | |
881 | ||
882 | The list of cases is rearranged into a binary tree, | |
883 | nearly optimal assuming equal probability for each case. | |
884 | ||
885 | The tree is transformed into RTL, eliminating redundant | |
886 | test conditions at the same time. | |
887 | ||
888 | If program flow could reach the end of the decision tree | |
889 | an unconditional jump to the default code is emitted. | |
7efcb746 | 890 | |
04a40cb9 SB |
891 | The above process is unaware of the CFG. The caller has to fix up |
892 | the CFG itself. This is done in cfgexpand.c. */ | |
7efcb746 | 893 | |
04a40cb9 SB |
894 | static void |
895 | emit_case_decision_tree (tree index_expr, tree index_type, | |
a4da41e1 ER |
896 | struct case_node *case_list, rtx default_label, |
897 | int default_prob) | |
04a40cb9 SB |
898 | { |
899 | rtx index = expand_normal (index_expr); | |
900 | ||
901 | if (GET_MODE_CLASS (GET_MODE (index)) == MODE_INT | |
902 | && ! have_insn_for (COMPARE, GET_MODE (index))) | |
903 | { | |
904 | int unsignedp = TYPE_UNSIGNED (index_type); | |
905 | enum machine_mode wider_mode; | |
906 | for (wider_mode = GET_MODE (index); wider_mode != VOIDmode; | |
907 | wider_mode = GET_MODE_WIDER_MODE (wider_mode)) | |
908 | if (have_insn_for (COMPARE, wider_mode)) | |
909 | { | |
910 | index = convert_to_mode (wider_mode, index, unsignedp); | |
911 | break; | |
912 | } | |
913 | } | |
6ac1b3a4 | 914 | |
28d81abb RK |
915 | do_pending_stack_adjust (); |
916 | ||
04a40cb9 | 917 | if (MEM_P (index)) |
28d81abb | 918 | { |
04a40cb9 SB |
919 | index = copy_to_reg (index); |
920 | if (TREE_CODE (index_expr) == SSA_NAME) | |
921 | set_reg_attrs_for_decl_rtl (SSA_NAME_VAR (index_expr), index); | |
922 | } | |
eb172681 | 923 | |
04a40cb9 | 924 | balance_case_nodes (&case_list, NULL); |
5100d114 | 925 | |
7ee2468b | 926 | if (dump_file && (dump_flags & TDF_DETAILS)) |
04a40cb9 SB |
927 | { |
928 | int indent_step = ceil_log2 (TYPE_PRECISION (index_type)) + 2; | |
929 | fprintf (dump_file, ";; Expanding GIMPLE switch as decision tree:\n"); | |
930 | dump_case_nodes (dump_file, case_list, indent_step, 0); | |
931 | } | |
4e0148df | 932 | |
a4da41e1 | 933 | emit_case_nodes (index, case_list, default_label, default_prob, index_type); |
04a40cb9 SB |
934 | if (default_label) |
935 | emit_jump (default_label); | |
936 | } | |
eb172681 | 937 | |
a4da41e1 ER |
938 | /* Return the sum of probabilities of outgoing edges of basic block BB. */ |
939 | ||
940 | static int | |
941 | get_outgoing_edge_probs (basic_block bb) | |
942 | { | |
943 | edge e; | |
944 | edge_iterator ei; | |
945 | int prob_sum = 0; | |
0f379f76 ER |
946 | if (!bb) |
947 | return 0; | |
c3284718 | 948 | FOR_EACH_EDGE (e, ei, bb->succs) |
a4da41e1 ER |
949 | prob_sum += e->probability; |
950 | return prob_sum; | |
951 | } | |
952 | ||
953 | /* Computes the conditional probability of jumping to a target if the branch | |
954 | instruction is executed. | |
955 | TARGET_PROB is the estimated probability of jumping to a target relative | |
956 | to some basic block BB. | |
957 | BASE_PROB is the probability of reaching the branch instruction relative | |
958 | to the same basic block BB. */ | |
959 | ||
960 | static inline int | |
961 | conditional_probability (int target_prob, int base_prob) | |
962 | { | |
963 | if (base_prob > 0) | |
964 | { | |
965 | gcc_assert (target_prob >= 0); | |
966 | gcc_assert (target_prob <= base_prob); | |
8ddb5a29 | 967 | return GCOV_COMPUTE_SCALE (target_prob, base_prob); |
a4da41e1 ER |
968 | } |
969 | return -1; | |
970 | } | |
971 | ||
04a40cb9 SB |
972 | /* Generate a dispatch tabler, switching on INDEX_EXPR and jumping to |
973 | one of the labels in CASE_LIST or to the DEFAULT_LABEL. | |
974 | MINVAL, MAXVAL, and RANGE are the extrema and range of the case | |
a4da41e1 | 975 | labels in CASE_LIST. STMT_BB is the basic block containing the statement. |
eb172681 | 976 | |
04a40cb9 SB |
977 | First, a jump insn is emitted. First we try "casesi". If that |
978 | fails, try "tablejump". A target *must* have one of them (or both). | |
979 | ||
980 | Then, a table with the target labels is emitted. | |
981 | ||
982 | The process is unaware of the CFG. The caller has to fix up | |
983 | the CFG itself. This is done in cfgexpand.c. */ | |
984 | ||
985 | static void | |
986 | emit_case_dispatch_table (tree index_expr, tree index_type, | |
987 | struct case_node *case_list, rtx default_label, | |
a4da41e1 ER |
988 | tree minval, tree maxval, tree range, |
989 | basic_block stmt_bb) | |
04a40cb9 SB |
990 | { |
991 | int i, ncases; | |
992 | struct case_node *n; | |
993 | rtx *labelvec; | |
994 | rtx fallback_label = label_rtx (case_list->code_label); | |
995 | rtx table_label = gen_label_rtx (); | |
a4da41e1 | 996 | bool has_gaps = false; |
c3284718 | 997 | edge default_edge = stmt_bb ? EDGE_SUCC (stmt_bb, 0) : NULL; |
0f379f76 | 998 | int default_prob = default_edge ? default_edge->probability : 0; |
a4da41e1 ER |
999 | int base = get_outgoing_edge_probs (stmt_bb); |
1000 | bool try_with_tablejump = false; | |
1001 | ||
1002 | int new_default_prob = conditional_probability (default_prob, | |
1003 | base); | |
28d81abb | 1004 | |
04a40cb9 | 1005 | if (! try_casesi (index_type, index_expr, minval, range, |
a4da41e1 ER |
1006 | table_label, default_label, fallback_label, |
1007 | new_default_prob)) | |
04a40cb9 | 1008 | { |
04a40cb9 SB |
1009 | /* Index jumptables from zero for suitable values of minval to avoid |
1010 | a subtraction. For the rationale see: | |
1011 | "http://gcc.gnu.org/ml/gcc-patches/2001-10/msg01234.html". */ | |
1012 | if (optimize_insn_for_speed_p () | |
1013 | && compare_tree_int (minval, 0) > 0 | |
1014 | && compare_tree_int (minval, 3) < 0) | |
28d81abb | 1015 | { |
04a40cb9 SB |
1016 | minval = build_int_cst (index_type, 0); |
1017 | range = maxval; | |
a4da41e1 | 1018 | has_gaps = true; |
28d81abb | 1019 | } |
a4da41e1 | 1020 | try_with_tablejump = true; |
04a40cb9 | 1021 | } |
28d81abb | 1022 | |
04a40cb9 | 1023 | /* Get table of labels to jump to, in order of case index. */ |
28d81abb | 1024 | |
9439e9a1 | 1025 | ncases = tree_to_shwi (range) + 1; |
04a40cb9 SB |
1026 | labelvec = XALLOCAVEC (rtx, ncases); |
1027 | memset (labelvec, 0, ncases * sizeof (rtx)); | |
28d81abb | 1028 | |
04a40cb9 SB |
1029 | for (n = case_list; n; n = n->right) |
1030 | { | |
1031 | /* Compute the low and high bounds relative to the minimum | |
1032 | value since that should fit in a HOST_WIDE_INT while the | |
1033 | actual values may not. */ | |
1034 | HOST_WIDE_INT i_low | |
386b1f1f RS |
1035 | = tree_to_uhwi (fold_build2 (MINUS_EXPR, index_type, |
1036 | n->low, minval)); | |
04a40cb9 | 1037 | HOST_WIDE_INT i_high |
386b1f1f RS |
1038 | = tree_to_uhwi (fold_build2 (MINUS_EXPR, index_type, |
1039 | n->high, minval)); | |
04a40cb9 SB |
1040 | HOST_WIDE_INT i; |
1041 | ||
1042 | for (i = i_low; i <= i_high; i ++) | |
1043 | labelvec[i] | |
1044 | = gen_rtx_LABEL_REF (Pmode, label_rtx (n->code_label)); | |
1045 | } | |
28d81abb | 1046 | |
04a40cb9 SB |
1047 | /* Fill in the gaps with the default. We may have gaps at |
1048 | the beginning if we tried to avoid the minval subtraction, | |
1049 | so substitute some label even if the default label was | |
1050 | deemed unreachable. */ | |
1051 | if (!default_label) | |
1052 | default_label = fallback_label; | |
1053 | for (i = 0; i < ncases; i++) | |
1054 | if (labelvec[i] == 0) | |
a4da41e1 ER |
1055 | { |
1056 | has_gaps = true; | |
1057 | labelvec[i] = gen_rtx_LABEL_REF (Pmode, default_label); | |
1058 | } | |
1059 | ||
1060 | if (has_gaps) | |
1061 | { | |
1062 | /* There is at least one entry in the jump table that jumps | |
1063 | to default label. The default label can either be reached | |
1064 | through the indirect jump or the direct conditional jump | |
1065 | before that. Split the probability of reaching the | |
1066 | default label among these two jumps. */ | |
1067 | new_default_prob = conditional_probability (default_prob/2, | |
1068 | base); | |
1069 | default_prob /= 2; | |
1070 | base -= default_prob; | |
1071 | } | |
1072 | else | |
1073 | { | |
1074 | base -= default_prob; | |
1075 | default_prob = 0; | |
1076 | } | |
1077 | ||
0f379f76 ER |
1078 | if (default_edge) |
1079 | default_edge->probability = default_prob; | |
a4da41e1 ER |
1080 | |
1081 | /* We have altered the probability of the default edge. So the probabilities | |
1082 | of all other edges need to be adjusted so that it sums up to | |
1083 | REG_BR_PROB_BASE. */ | |
1084 | if (base) | |
1085 | { | |
1086 | edge e; | |
1087 | edge_iterator ei; | |
1088 | FOR_EACH_EDGE (e, ei, stmt_bb->succs) | |
8ddb5a29 | 1089 | e->probability = GCOV_COMPUTE_SCALE (e->probability, base); |
a4da41e1 | 1090 | } |
04a40cb9 | 1091 | |
a4da41e1 ER |
1092 | if (try_with_tablejump) |
1093 | { | |
1094 | bool ok = try_tablejump (index_type, index_expr, minval, range, | |
1095 | table_label, default_label, new_default_prob); | |
1096 | gcc_assert (ok); | |
1097 | } | |
04a40cb9 SB |
1098 | /* Output the table. */ |
1099 | emit_label (table_label); | |
1100 | ||
1101 | if (CASE_VECTOR_PC_RELATIVE || flag_pic) | |
39718607 SB |
1102 | emit_jump_table_data (gen_rtx_ADDR_DIFF_VEC (CASE_VECTOR_MODE, |
1103 | gen_rtx_LABEL_REF (Pmode, | |
1104 | table_label), | |
1105 | gen_rtvec_v (ncases, labelvec), | |
1106 | const0_rtx, const0_rtx)); | |
04a40cb9 | 1107 | else |
39718607 SB |
1108 | emit_jump_table_data (gen_rtx_ADDR_VEC (CASE_VECTOR_MODE, |
1109 | gen_rtvec_v (ncases, labelvec))); | |
28d81abb | 1110 | |
04a40cb9 SB |
1111 | /* Record no drop-through after the table. */ |
1112 | emit_barrier (); | |
1113 | } | |
5100d114 | 1114 | |
a4da41e1 ER |
1115 | /* Reset the aux field of all outgoing edges of basic block BB. */ |
1116 | ||
1117 | static inline void | |
1118 | reset_out_edges_aux (basic_block bb) | |
1119 | { | |
1120 | edge e; | |
1121 | edge_iterator ei; | |
c3284718 | 1122 | FOR_EACH_EDGE (e, ei, bb->succs) |
a4da41e1 ER |
1123 | e->aux = (void *)0; |
1124 | } | |
1125 | ||
1126 | /* Compute the number of case labels that correspond to each outgoing edge of | |
1127 | STMT. Record this information in the aux field of the edge. */ | |
1128 | ||
1129 | static inline void | |
1130 | compute_cases_per_edge (gimple stmt) | |
1131 | { | |
1132 | basic_block bb = gimple_bb (stmt); | |
1133 | reset_out_edges_aux (bb); | |
1134 | int ncases = gimple_switch_num_labels (stmt); | |
1135 | for (int i = ncases - 1; i >= 1; --i) | |
1136 | { | |
1137 | tree elt = gimple_switch_label (stmt, i); | |
1138 | tree lab = CASE_LABEL (elt); | |
1139 | basic_block case_bb = label_to_block_fn (cfun, lab); | |
1140 | edge case_edge = find_edge (bb, case_bb); | |
58ccdcc8 | 1141 | case_edge->aux = (void *)((intptr_t)(case_edge->aux) + 1); |
a4da41e1 ER |
1142 | } |
1143 | } | |
1144 | ||
04a40cb9 SB |
1145 | /* Terminate a case (Pascal/Ada) or switch (C) statement |
1146 | in which ORIG_INDEX is the expression to be tested. | |
1147 | If ORIG_TYPE is not NULL, it is the original ORIG_INDEX | |
1148 | type as given in the source before any compiler conversions. | |
1149 | Generate the code to test it and jump to the right place. */ | |
5100d114 | 1150 | |
04a40cb9 SB |
1151 | void |
1152 | expand_case (gimple stmt) | |
1153 | { | |
1154 | tree minval = NULL_TREE, maxval = NULL_TREE, range = NULL_TREE; | |
1155 | rtx default_label = NULL_RTX; | |
1156 | unsigned int count, uniq; | |
fd8d363e | 1157 | int i; |
04a40cb9 SB |
1158 | int ncases = gimple_switch_num_labels (stmt); |
1159 | tree index_expr = gimple_switch_index (stmt); | |
1160 | tree index_type = TREE_TYPE (index_expr); | |
04a40cb9 | 1161 | tree elt; |
a4da41e1 | 1162 | basic_block bb = gimple_bb (stmt); |
1ff37128 | 1163 | |
04a40cb9 SB |
1164 | /* A list of case labels; it is first built as a list and it may then |
1165 | be rearranged into a nearly balanced binary tree. */ | |
1166 | struct case_node *case_list = 0; | |
1ff37128 | 1167 | |
04a40cb9 SB |
1168 | /* A pool for case nodes. */ |
1169 | alloc_pool case_node_pool; | |
786de7eb | 1170 | |
04a40cb9 SB |
1171 | /* An ERROR_MARK occurs for various reasons including invalid data type. |
1172 | ??? Can this still happen, with GIMPLE and all? */ | |
1173 | if (index_type == error_mark_node) | |
1174 | return; | |
28d81abb | 1175 | |
04a40cb9 SB |
1176 | /* cleanup_tree_cfg removes all SWITCH_EXPR with their index |
1177 | expressions being INTEGER_CST. */ | |
1178 | gcc_assert (TREE_CODE (index_expr) != INTEGER_CST); | |
1179 | ||
1180 | case_node_pool = create_alloc_pool ("struct case_node pool", | |
1181 | sizeof (struct case_node), | |
1182 | 100); | |
28d81abb | 1183 | |
04a40cb9 | 1184 | do_pending_stack_adjust (); |
28d81abb | 1185 | |
fd8d363e SB |
1186 | /* Find the default case target label. */ |
1187 | default_label = label_rtx (CASE_LABEL (gimple_switch_default_label (stmt))); | |
c3284718 | 1188 | edge default_edge = EDGE_SUCC (bb, 0); |
a4da41e1 | 1189 | int default_prob = default_edge->probability; |
28d81abb | 1190 | |
04a40cb9 | 1191 | /* Get upper and lower bounds of case values. */ |
fd8d363e | 1192 | elt = gimple_switch_label (stmt, 1); |
04a40cb9 SB |
1193 | minval = fold_convert (index_type, CASE_LOW (elt)); |
1194 | elt = gimple_switch_label (stmt, ncases - 1); | |
1195 | if (CASE_HIGH (elt)) | |
1196 | maxval = fold_convert (index_type, CASE_HIGH (elt)); | |
1197 | else | |
1198 | maxval = fold_convert (index_type, CASE_LOW (elt)); | |
1199 | ||
1200 | /* Compute span of values. */ | |
1201 | range = fold_build2 (MINUS_EXPR, index_type, maxval, minval); | |
28d81abb | 1202 | |
04a40cb9 SB |
1203 | /* Listify the labels queue and gather some numbers to decide |
1204 | how to expand this switch(). */ | |
1205 | uniq = 0; | |
1206 | count = 0; | |
9a1b6b7a | 1207 | struct pointer_set_t *seen_labels = pointer_set_create (); |
a4da41e1 ER |
1208 | compute_cases_per_edge (stmt); |
1209 | ||
1210 | for (i = ncases - 1; i >= 1; --i) | |
04a40cb9 | 1211 | { |
04a40cb9 | 1212 | elt = gimple_switch_label (stmt, i); |
9a1b6b7a | 1213 | tree low = CASE_LOW (elt); |
04a40cb9 | 1214 | gcc_assert (low); |
9a1b6b7a | 1215 | tree high = CASE_HIGH (elt); |
04a40cb9 | 1216 | gcc_assert (! high || tree_int_cst_lt (low, high)); |
9a1b6b7a | 1217 | tree lab = CASE_LABEL (elt); |
04a40cb9 SB |
1218 | |
1219 | /* Count the elements. | |
1220 | A range counts double, since it requires two compares. */ | |
1221 | count++; | |
1222 | if (high) | |
1223 | count++; | |
1224 | ||
1225 | /* If we have not seen this label yet, then increase the | |
1226 | number of unique case node targets seen. */ | |
9a1b6b7a | 1227 | if (!pointer_set_insert (seen_labels, lab)) |
04a40cb9 SB |
1228 | uniq++; |
1229 | ||
9a1b6b7a SB |
1230 | /* The bounds on the case range, LOW and HIGH, have to be converted |
1231 | to case's index type TYPE. Note that the original type of the | |
1232 | case index in the source code is usually "lost" during | |
1233 | gimplification due to type promotion, but the case labels retain the | |
1234 | original type. Make sure to drop overflow flags. */ | |
1235 | low = fold_convert (index_type, low); | |
1236 | if (TREE_OVERFLOW (low)) | |
807e902e | 1237 | low = wide_int_to_tree (index_type, low); |
9a1b6b7a | 1238 | |
04a40cb9 SB |
1239 | /* The canonical from of a case label in GIMPLE is that a simple case |
1240 | has an empty CASE_HIGH. For the casesi and tablejump expanders, | |
1241 | the back ends want simple cases to have high == low. */ | |
1242 | if (! high) | |
1243 | high = low; | |
9a1b6b7a SB |
1244 | high = fold_convert (index_type, high); |
1245 | if (TREE_OVERFLOW (high)) | |
807e902e | 1246 | high = wide_int_to_tree (index_type, high); |
9a1b6b7a | 1247 | |
a4da41e1 ER |
1248 | basic_block case_bb = label_to_block_fn (cfun, lab); |
1249 | edge case_edge = find_edge (bb, case_bb); | |
1250 | case_list = add_case_node ( | |
1251 | case_list, low, high, lab, | |
58ccdcc8 | 1252 | case_edge->probability / (intptr_t)(case_edge->aux), |
a4da41e1 | 1253 | case_node_pool); |
28d81abb | 1254 | } |
9a1b6b7a | 1255 | pointer_set_destroy (seen_labels); |
a4da41e1 | 1256 | reset_out_edges_aux (bb); |
04a40cb9 SB |
1257 | |
1258 | /* cleanup_tree_cfg removes all SWITCH_EXPR with a single | |
1259 | destination, such as one with a default case only. | |
1260 | It also removes cases that are out of range for the switch | |
1261 | type, so we should never get a zero here. */ | |
1262 | gcc_assert (count > 0); | |
1263 | ||
9a1b6b7a | 1264 | rtx before_case = get_last_insn (); |
04a40cb9 SB |
1265 | |
1266 | /* Decide how to expand this switch. | |
1267 | The two options at this point are a dispatch table (casesi or | |
1268 | tablejump) or a decision tree. */ | |
1269 | ||
1270 | if (expand_switch_as_decision_tree_p (range, uniq, count)) | |
1271 | emit_case_decision_tree (index_expr, index_type, | |
a4da41e1 ER |
1272 | case_list, default_label, |
1273 | default_prob); | |
04a40cb9 SB |
1274 | else |
1275 | emit_case_dispatch_table (index_expr, index_type, | |
1276 | case_list, default_label, | |
a4da41e1 | 1277 | minval, maxval, range, bb); |
04a40cb9 | 1278 | |
9a1b6b7a | 1279 | reorder_insns (NEXT_INSN (before_case), get_last_insn (), before_case); |
1b0cb6fc | 1280 | |
28d81abb | 1281 | free_temp_slots (); |
6ac1b3a4 | 1282 | free_alloc_pool (case_node_pool); |
28d81abb RK |
1283 | } |
1284 | ||
9a1b6b7a SB |
1285 | /* Expand the dispatch to a short decrement chain if there are few cases |
1286 | to dispatch to. Likewise if neither casesi nor tablejump is available, | |
1287 | or if flag_jump_tables is set. Otherwise, expand as a casesi or a | |
1288 | tablejump. The index mode is always the mode of integer_type_node. | |
1289 | Trap if no case matches the index. | |
28d81abb | 1290 | |
9a1b6b7a SB |
1291 | DISPATCH_INDEX is the index expression to switch on. It should be a |
1292 | memory or register operand. | |
1293 | ||
1294 | DISPATCH_TABLE is a set of case labels. The set should be sorted in | |
1295 | ascending order, be contiguous, starting with value 0, and contain only | |
1296 | single-valued case labels. */ | |
1297 | ||
1298 | void | |
1299 | expand_sjlj_dispatch_table (rtx dispatch_index, | |
9771b263 | 1300 | vec<tree> dispatch_table) |
28d81abb | 1301 | { |
9a1b6b7a SB |
1302 | tree index_type = integer_type_node; |
1303 | enum machine_mode index_mode = TYPE_MODE (index_type); | |
1304 | ||
9771b263 | 1305 | int ncases = dispatch_table.length (); |
9a1b6b7a SB |
1306 | |
1307 | do_pending_stack_adjust (); | |
1308 | rtx before_case = get_last_insn (); | |
1309 | ||
1310 | /* Expand as a decrement-chain if there are 5 or fewer dispatch | |
1311 | labels. This covers more than 98% of the cases in libjava, | |
1312 | and seems to be a reasonable compromise between the "old way" | |
1313 | of expanding as a decision tree or dispatch table vs. the "new | |
1314 | way" with decrement chain or dispatch table. */ | |
9771b263 | 1315 | if (dispatch_table.length () <= 5 |
9a1b6b7a SB |
1316 | || (!HAVE_casesi && !HAVE_tablejump) |
1317 | || !flag_jump_tables) | |
1318 | { | |
1319 | /* Expand the dispatch as a decrement chain: | |
1320 | ||
1321 | "switch(index) {case 0: do_0; case 1: do_1; ...; case N: do_N;}" | |
1322 | ||
1323 | ==> | |
1324 | ||
1325 | if (index == 0) do_0; else index--; | |
1326 | if (index == 0) do_1; else index--; | |
1327 | ... | |
1328 | if (index == 0) do_N; else index--; | |
1329 | ||
1330 | This is more efficient than a dispatch table on most machines. | |
1331 | The last "index--" is redundant but the code is trivially dead | |
1332 | and will be cleaned up by later passes. */ | |
1333 | rtx index = copy_to_mode_reg (index_mode, dispatch_index); | |
1334 | rtx zero = CONST0_RTX (index_mode); | |
1335 | for (int i = 0; i < ncases; i++) | |
1336 | { | |
9771b263 | 1337 | tree elt = dispatch_table[i]; |
9a1b6b7a | 1338 | rtx lab = label_rtx (CASE_LABEL (elt)); |
a4da41e1 | 1339 | do_jump_if_equal (index_mode, index, zero, lab, 0, -1); |
9a1b6b7a SB |
1340 | force_expand_binop (index_mode, sub_optab, |
1341 | index, CONST1_RTX (index_mode), | |
1342 | index, 0, OPTAB_DIRECT); | |
1343 | } | |
1344 | } | |
1345 | else | |
1346 | { | |
1347 | /* Similar to expand_case, but much simpler. */ | |
1348 | struct case_node *case_list = 0; | |
1349 | alloc_pool case_node_pool = create_alloc_pool ("struct sjlj_case pool", | |
1350 | sizeof (struct case_node), | |
1351 | ncases); | |
1352 | tree index_expr = make_tree (index_type, dispatch_index); | |
1353 | tree minval = build_int_cst (index_type, 0); | |
9771b263 | 1354 | tree maxval = CASE_LOW (dispatch_table.last ()); |
9a1b6b7a SB |
1355 | tree range = maxval; |
1356 | rtx default_label = gen_label_rtx (); | |
1357 | ||
0da911e9 | 1358 | for (int i = ncases - 1; i >= 0; --i) |
9a1b6b7a | 1359 | { |
9771b263 | 1360 | tree elt = dispatch_table[i]; |
9a1b6b7a SB |
1361 | tree low = CASE_LOW (elt); |
1362 | tree lab = CASE_LABEL (elt); | |
a4da41e1 | 1363 | case_list = add_case_node (case_list, low, low, lab, 0, case_node_pool); |
9a1b6b7a SB |
1364 | } |
1365 | ||
1366 | emit_case_dispatch_table (index_expr, index_type, | |
1367 | case_list, default_label, | |
0f379f76 ER |
1368 | minval, maxval, range, |
1369 | BLOCK_FOR_INSN (before_case)); | |
9a1b6b7a SB |
1370 | emit_label (default_label); |
1371 | free_alloc_pool (case_node_pool); | |
1372 | } | |
1373 | ||
1374 | /* Dispatching something not handled? Trap! */ | |
1375 | expand_builtin_trap (); | |
1376 | ||
1377 | reorder_insns (NEXT_INSN (before_case), get_last_insn (), before_case); | |
1378 | ||
1379 | free_temp_slots (); | |
28d81abb | 1380 | } |
9a1b6b7a | 1381 | |
28d81abb | 1382 | \f |
28d81abb RK |
1383 | /* Take an ordered list of case nodes |
1384 | and transform them into a near optimal binary tree, | |
6dc42e49 | 1385 | on the assumption that any target code selection value is as |
28d81abb RK |
1386 | likely as any other. |
1387 | ||
1388 | The transformation is performed by splitting the ordered | |
1389 | list into two equal sections plus a pivot. The parts are | |
1390 | then attached to the pivot as left and right branches. Each | |
38e01259 | 1391 | branch is then transformed recursively. */ |
28d81abb RK |
1392 | |
1393 | static void | |
46c5ad27 | 1394 | balance_case_nodes (case_node_ptr *head, case_node_ptr parent) |
28d81abb | 1395 | { |
b3694847 | 1396 | case_node_ptr np; |
28d81abb RK |
1397 | |
1398 | np = *head; | |
1399 | if (np) | |
1400 | { | |
28d81abb RK |
1401 | int i = 0; |
1402 | int ranges = 0; | |
b3694847 | 1403 | case_node_ptr *npp; |
28d81abb RK |
1404 | case_node_ptr left; |
1405 | ||
1406 | /* Count the number of entries on branch. Also count the ranges. */ | |
1407 | ||
1408 | while (np) | |
1409 | { | |
1410 | if (!tree_int_cst_equal (np->low, np->high)) | |
c5c20c55 | 1411 | ranges++; |
28d81abb RK |
1412 | |
1413 | i++; | |
1414 | np = np->right; | |
1415 | } | |
1416 | ||
1417 | if (i > 2) | |
1418 | { | |
1419 | /* Split this list if it is long enough for that to help. */ | |
1420 | npp = head; | |
1421 | left = *npp; | |
c5c20c55 | 1422 | |
28d81abb | 1423 | /* If there are just three nodes, split at the middle one. */ |
c5c20c55 | 1424 | if (i == 3) |
28d81abb RK |
1425 | npp = &(*npp)->right; |
1426 | else | |
1427 | { | |
1428 | /* Find the place in the list that bisects the list's total cost, | |
1429 | where ranges count as 2. | |
1430 | Here I gets half the total cost. */ | |
1431 | i = (i + ranges + 1) / 2; | |
1432 | while (1) | |
1433 | { | |
1434 | /* Skip nodes while their cost does not reach that amount. */ | |
1435 | if (!tree_int_cst_equal ((*npp)->low, (*npp)->high)) | |
1436 | i--; | |
1437 | i--; | |
1438 | if (i <= 0) | |
1439 | break; | |
1440 | npp = &(*npp)->right; | |
1441 | } | |
1442 | } | |
1443 | *head = np = *npp; | |
1444 | *npp = 0; | |
1445 | np->parent = parent; | |
1446 | np->left = left; | |
1447 | ||
1448 | /* Optimize each of the two split parts. */ | |
1449 | balance_case_nodes (&np->left, np); | |
1450 | balance_case_nodes (&np->right, np); | |
a4da41e1 ER |
1451 | np->subtree_prob = np->prob; |
1452 | np->subtree_prob += np->left->subtree_prob; | |
1453 | np->subtree_prob += np->right->subtree_prob; | |
28d81abb RK |
1454 | } |
1455 | else | |
1456 | { | |
1457 | /* Else leave this branch as one level, | |
1458 | but fill in `parent' fields. */ | |
1459 | np = *head; | |
1460 | np->parent = parent; | |
a4da41e1 | 1461 | np->subtree_prob = np->prob; |
28d81abb | 1462 | for (; np->right; np = np->right) |
a4da41e1 ER |
1463 | { |
1464 | np->right->parent = np; | |
1465 | (*head)->subtree_prob += np->right->subtree_prob; | |
1466 | } | |
28d81abb RK |
1467 | } |
1468 | } | |
1469 | } | |
1470 | \f | |
1471 | /* Search the parent sections of the case node tree | |
1472 | to see if a test for the lower bound of NODE would be redundant. | |
1473 | INDEX_TYPE is the type of the index expression. | |
1474 | ||
1475 | The instructions to generate the case decision tree are | |
1476 | output in the same order as nodes are processed so it is | |
1477 | known that if a parent node checks the range of the current | |
1478 | node minus one that the current node is bounded at its lower | |
1479 | span. Thus the test would be redundant. */ | |
1480 | ||
1481 | static int | |
46c5ad27 | 1482 | node_has_low_bound (case_node_ptr node, tree index_type) |
28d81abb RK |
1483 | { |
1484 | tree low_minus_one; | |
1485 | case_node_ptr pnode; | |
1486 | ||
1487 | /* If the lower bound of this node is the lowest value in the index type, | |
1488 | we need not test it. */ | |
1489 | ||
1490 | if (tree_int_cst_equal (node->low, TYPE_MIN_VALUE (index_type))) | |
1491 | return 1; | |
1492 | ||
1493 | /* If this node has a left branch, the value at the left must be less | |
1494 | than that at this node, so it cannot be bounded at the bottom and | |
1495 | we need not bother testing any further. */ | |
1496 | ||
1497 | if (node->left) | |
1498 | return 0; | |
1499 | ||
4845b383 | 1500 | low_minus_one = fold_build2 (MINUS_EXPR, TREE_TYPE (node->low), |
3bedcc89 RG |
1501 | node->low, |
1502 | build_int_cst (TREE_TYPE (node->low), 1)); | |
28d81abb RK |
1503 | |
1504 | /* If the subtraction above overflowed, we can't verify anything. | |
1505 | Otherwise, look for a parent that tests our value - 1. */ | |
1506 | ||
1507 | if (! tree_int_cst_lt (low_minus_one, node->low)) | |
1508 | return 0; | |
1509 | ||
1510 | for (pnode = node->parent; pnode; pnode = pnode->parent) | |
1511 | if (tree_int_cst_equal (low_minus_one, pnode->high)) | |
1512 | return 1; | |
1513 | ||
1514 | return 0; | |
1515 | } | |
1516 | ||
1517 | /* Search the parent sections of the case node tree | |
1518 | to see if a test for the upper bound of NODE would be redundant. | |
1519 | INDEX_TYPE is the type of the index expression. | |
1520 | ||
1521 | The instructions to generate the case decision tree are | |
1522 | output in the same order as nodes are processed so it is | |
1523 | known that if a parent node checks the range of the current | |
1524 | node plus one that the current node is bounded at its upper | |
1525 | span. Thus the test would be redundant. */ | |
1526 | ||
1527 | static int | |
46c5ad27 | 1528 | node_has_high_bound (case_node_ptr node, tree index_type) |
28d81abb RK |
1529 | { |
1530 | tree high_plus_one; | |
1531 | case_node_ptr pnode; | |
1532 | ||
e1ee5cdc RH |
1533 | /* If there is no upper bound, obviously no test is needed. */ |
1534 | ||
1535 | if (TYPE_MAX_VALUE (index_type) == NULL) | |
1536 | return 1; | |
1537 | ||
28d81abb RK |
1538 | /* If the upper bound of this node is the highest value in the type |
1539 | of the index expression, we need not test against it. */ | |
1540 | ||
1541 | if (tree_int_cst_equal (node->high, TYPE_MAX_VALUE (index_type))) | |
1542 | return 1; | |
1543 | ||
1544 | /* If this node has a right branch, the value at the right must be greater | |
1545 | than that at this node, so it cannot be bounded at the top and | |
1546 | we need not bother testing any further. */ | |
1547 | ||
1548 | if (node->right) | |
1549 | return 0; | |
1550 | ||
4845b383 | 1551 | high_plus_one = fold_build2 (PLUS_EXPR, TREE_TYPE (node->high), |
3bedcc89 RG |
1552 | node->high, |
1553 | build_int_cst (TREE_TYPE (node->high), 1)); | |
28d81abb RK |
1554 | |
1555 | /* If the addition above overflowed, we can't verify anything. | |
1556 | Otherwise, look for a parent that tests our value + 1. */ | |
1557 | ||
1558 | if (! tree_int_cst_lt (node->high, high_plus_one)) | |
1559 | return 0; | |
1560 | ||
1561 | for (pnode = node->parent; pnode; pnode = pnode->parent) | |
1562 | if (tree_int_cst_equal (high_plus_one, pnode->low)) | |
1563 | return 1; | |
1564 | ||
1565 | return 0; | |
1566 | } | |
1567 | ||
1568 | /* Search the parent sections of the | |
1569 | case node tree to see if both tests for the upper and lower | |
1570 | bounds of NODE would be redundant. */ | |
1571 | ||
1572 | static int | |
46c5ad27 | 1573 | node_is_bounded (case_node_ptr node, tree index_type) |
28d81abb RK |
1574 | { |
1575 | return (node_has_low_bound (node, index_type) | |
1576 | && node_has_high_bound (node, index_type)); | |
1577 | } | |
28d81abb | 1578 | \f |
a4da41e1 | 1579 | |
28d81abb RK |
1580 | /* Emit step-by-step code to select a case for the value of INDEX. |
1581 | The thus generated decision tree follows the form of the | |
1582 | case-node binary tree NODE, whose nodes represent test conditions. | |
1583 | INDEX_TYPE is the type of the index of the switch. | |
1584 | ||
1585 | Care is taken to prune redundant tests from the decision tree | |
1586 | by detecting any boundary conditions already checked by | |
1587 | emitted rtx. (See node_has_high_bound, node_has_low_bound | |
1588 | and node_is_bounded, above.) | |
1589 | ||
1590 | Where the test conditions can be shown to be redundant we emit | |
1591 | an unconditional jump to the target code. As a further | |
1592 | optimization, the subordinates of a tree node are examined to | |
1593 | check for bounded nodes. In this case conditional and/or | |
1594 | unconditional jumps as a result of the boundary check for the | |
1595 | current node are arranged to target the subordinates associated | |
38e01259 | 1596 | code for out of bound conditions on the current node. |
28d81abb | 1597 | |
f72aed24 | 1598 | We can assume that when control reaches the code generated here, |
28d81abb RK |
1599 | the index value has already been compared with the parents |
1600 | of this node, and determined to be on the same side of each parent | |
1601 | as this node is. Thus, if this node tests for the value 51, | |
1602 | and a parent tested for 52, we don't need to consider | |
1603 | the possibility of a value greater than 51. If another parent | |
1604 | tests for the value 50, then this node need not test anything. */ | |
1605 | ||
1606 | static void | |
46c5ad27 | 1607 | emit_case_nodes (rtx index, case_node_ptr node, rtx default_label, |
a4da41e1 | 1608 | int default_prob, tree index_type) |
28d81abb RK |
1609 | { |
1610 | /* If INDEX has an unsigned type, we must make unsigned branches. */ | |
8df83eae | 1611 | int unsignedp = TYPE_UNSIGNED (index_type); |
a4da41e1 ER |
1612 | int probability; |
1613 | int prob = node->prob, subtree_prob = node->subtree_prob; | |
28d81abb | 1614 | enum machine_mode mode = GET_MODE (index); |
69107307 | 1615 | enum machine_mode imode = TYPE_MODE (index_type); |
28d81abb | 1616 | |
f8318079 RS |
1617 | /* Handle indices detected as constant during RTL expansion. */ |
1618 | if (mode == VOIDmode) | |
1619 | mode = imode; | |
1620 | ||
28d81abb RK |
1621 | /* See if our parents have already tested everything for us. |
1622 | If they have, emit an unconditional jump for this node. */ | |
1623 | if (node_is_bounded (node, index_type)) | |
1624 | emit_jump (label_rtx (node->code_label)); | |
1625 | ||
1626 | else if (tree_int_cst_equal (node->low, node->high)) | |
1627 | { | |
a4da41e1 | 1628 | probability = conditional_probability (prob, subtree_prob + default_prob); |
28d81abb | 1629 | /* Node is single valued. First see if the index expression matches |
0f41302f | 1630 | this node and then check our children, if any. */ |
feb04780 | 1631 | do_jump_if_equal (mode, index, |
69107307 | 1632 | convert_modes (mode, imode, |
84217346 | 1633 | expand_normal (node->low), |
69107307 | 1634 | unsignedp), |
a4da41e1 ER |
1635 | label_rtx (node->code_label), unsignedp, probability); |
1636 | /* Since this case is taken at this point, reduce its weight from | |
1637 | subtree_weight. */ | |
1638 | subtree_prob -= prob; | |
28d81abb RK |
1639 | if (node->right != 0 && node->left != 0) |
1640 | { | |
1641 | /* This node has children on both sides. | |
1642 | Dispatch to one side or the other | |
1643 | by comparing the index value with this node's value. | |
1644 | If one subtree is bounded, check that one first, | |
1645 | so we can avoid real branches in the tree. */ | |
1646 | ||
1647 | if (node_is_bounded (node->right, index_type)) | |
1648 | { | |
a4da41e1 ER |
1649 | probability = conditional_probability ( |
1650 | node->right->prob, | |
1651 | subtree_prob + default_prob); | |
4381f7c2 | 1652 | emit_cmp_and_jump_insns (index, |
69107307 AO |
1653 | convert_modes |
1654 | (mode, imode, | |
84217346 | 1655 | expand_normal (node->high), |
69107307 | 1656 | unsignedp), |
d43e0b7d | 1657 | GT, NULL_RTX, mode, unsignedp, |
a4da41e1 ER |
1658 | label_rtx (node->right->code_label), |
1659 | probability); | |
1660 | emit_case_nodes (index, node->left, default_label, default_prob, | |
1661 | index_type); | |
28d81abb RK |
1662 | } |
1663 | ||
1664 | else if (node_is_bounded (node->left, index_type)) | |
1665 | { | |
a4da41e1 ER |
1666 | probability = conditional_probability ( |
1667 | node->left->prob, | |
1668 | subtree_prob + default_prob); | |
4381f7c2 | 1669 | emit_cmp_and_jump_insns (index, |
69107307 AO |
1670 | convert_modes |
1671 | (mode, imode, | |
84217346 | 1672 | expand_normal (node->high), |
69107307 | 1673 | unsignedp), |
d43e0b7d | 1674 | LT, NULL_RTX, mode, unsignedp, |
a4da41e1 ER |
1675 | label_rtx (node->left->code_label), |
1676 | probability); | |
1677 | emit_case_nodes (index, node->right, default_label, default_prob, index_type); | |
28d81abb RK |
1678 | } |
1679 | ||
43a21dfc KH |
1680 | /* If both children are single-valued cases with no |
1681 | children, finish up all the work. This way, we can save | |
1682 | one ordered comparison. */ | |
1683 | else if (tree_int_cst_equal (node->right->low, node->right->high) | |
1684 | && node->right->left == 0 | |
1685 | && node->right->right == 0 | |
1686 | && tree_int_cst_equal (node->left->low, node->left->high) | |
1687 | && node->left->left == 0 | |
1688 | && node->left->right == 0) | |
1689 | { | |
1690 | /* Neither node is bounded. First distinguish the two sides; | |
1691 | then emit the code for one side at a time. */ | |
1692 | ||
1693 | /* See if the value matches what the right hand side | |
1694 | wants. */ | |
a4da41e1 ER |
1695 | probability = conditional_probability ( |
1696 | node->right->prob, | |
1697 | subtree_prob + default_prob); | |
feb04780 | 1698 | do_jump_if_equal (mode, index, |
43a21dfc | 1699 | convert_modes (mode, imode, |
84217346 | 1700 | expand_normal (node->right->low), |
43a21dfc KH |
1701 | unsignedp), |
1702 | label_rtx (node->right->code_label), | |
a4da41e1 | 1703 | unsignedp, probability); |
43a21dfc KH |
1704 | |
1705 | /* See if the value matches what the left hand side | |
1706 | wants. */ | |
a4da41e1 ER |
1707 | probability = conditional_probability ( |
1708 | node->left->prob, | |
1709 | subtree_prob + default_prob); | |
feb04780 | 1710 | do_jump_if_equal (mode, index, |
43a21dfc | 1711 | convert_modes (mode, imode, |
84217346 | 1712 | expand_normal (node->left->low), |
43a21dfc KH |
1713 | unsignedp), |
1714 | label_rtx (node->left->code_label), | |
a4da41e1 | 1715 | unsignedp, probability); |
43a21dfc KH |
1716 | } |
1717 | ||
28d81abb RK |
1718 | else |
1719 | { | |
1720 | /* Neither node is bounded. First distinguish the two sides; | |
1721 | then emit the code for one side at a time. */ | |
1722 | ||
c2255bc4 | 1723 | tree test_label |
5368224f | 1724 | = build_decl (curr_insn_location (), |
c2255bc4 | 1725 | LABEL_DECL, NULL_TREE, NULL_TREE); |
28d81abb | 1726 | |
a4da41e1 ER |
1727 | /* The default label could be reached either through the right |
1728 | subtree or the left subtree. Divide the probability | |
1729 | equally. */ | |
1730 | probability = conditional_probability ( | |
1731 | node->right->subtree_prob + default_prob/2, | |
1732 | subtree_prob + default_prob); | |
28d81abb | 1733 | /* See if the value is on the right. */ |
4381f7c2 | 1734 | emit_cmp_and_jump_insns (index, |
69107307 AO |
1735 | convert_modes |
1736 | (mode, imode, | |
84217346 | 1737 | expand_normal (node->high), |
69107307 | 1738 | unsignedp), |
d43e0b7d | 1739 | GT, NULL_RTX, mode, unsignedp, |
a4da41e1 ER |
1740 | label_rtx (test_label), |
1741 | probability); | |
1742 | default_prob /= 2; | |
28d81abb RK |
1743 | |
1744 | /* Value must be on the left. | |
1745 | Handle the left-hand subtree. */ | |
a4da41e1 | 1746 | emit_case_nodes (index, node->left, default_label, default_prob, index_type); |
28d81abb RK |
1747 | /* If left-hand subtree does nothing, |
1748 | go to default. */ | |
b7814a18 RG |
1749 | if (default_label) |
1750 | emit_jump (default_label); | |
28d81abb RK |
1751 | |
1752 | /* Code branches here for the right-hand subtree. */ | |
1753 | expand_label (test_label); | |
a4da41e1 | 1754 | emit_case_nodes (index, node->right, default_label, default_prob, index_type); |
28d81abb RK |
1755 | } |
1756 | } | |
1757 | ||
1758 | else if (node->right != 0 && node->left == 0) | |
1759 | { | |
adb35797 | 1760 | /* Here we have a right child but no left so we issue a conditional |
28d81abb RK |
1761 | branch to default and process the right child. |
1762 | ||
adb35797 KH |
1763 | Omit the conditional branch to default if the right child |
1764 | does not have any children and is single valued; it would | |
1765 | cost too much space to save so little time. */ | |
28d81abb | 1766 | |
de14fd73 | 1767 | if (node->right->right || node->right->left |
28d81abb RK |
1768 | || !tree_int_cst_equal (node->right->low, node->right->high)) |
1769 | { | |
1770 | if (!node_has_low_bound (node, index_type)) | |
1771 | { | |
a4da41e1 ER |
1772 | probability = conditional_probability ( |
1773 | default_prob/2, | |
1774 | subtree_prob + default_prob); | |
4381f7c2 | 1775 | emit_cmp_and_jump_insns (index, |
69107307 AO |
1776 | convert_modes |
1777 | (mode, imode, | |
84217346 | 1778 | expand_normal (node->high), |
69107307 | 1779 | unsignedp), |
d43e0b7d | 1780 | LT, NULL_RTX, mode, unsignedp, |
a4da41e1 ER |
1781 | default_label, |
1782 | probability); | |
1783 | default_prob /= 2; | |
28d81abb RK |
1784 | } |
1785 | ||
a4da41e1 | 1786 | emit_case_nodes (index, node->right, default_label, default_prob, index_type); |
28d81abb RK |
1787 | } |
1788 | else | |
a4da41e1 ER |
1789 | { |
1790 | probability = conditional_probability ( | |
1791 | node->right->subtree_prob, | |
1792 | subtree_prob + default_prob); | |
1793 | /* We cannot process node->right normally | |
1794 | since we haven't ruled out the numbers less than | |
1795 | this node's value. So handle node->right explicitly. */ | |
1796 | do_jump_if_equal (mode, index, | |
1797 | convert_modes | |
1798 | (mode, imode, | |
1799 | expand_normal (node->right->low), | |
1800 | unsignedp), | |
1801 | label_rtx (node->right->code_label), unsignedp, probability); | |
1802 | } | |
1803 | } | |
28d81abb RK |
1804 | |
1805 | else if (node->right == 0 && node->left != 0) | |
1806 | { | |
1807 | /* Just one subtree, on the left. */ | |
4381f7c2 | 1808 | if (node->left->left || node->left->right |
28d81abb RK |
1809 | || !tree_int_cst_equal (node->left->low, node->left->high)) |
1810 | { | |
1811 | if (!node_has_high_bound (node, index_type)) | |
1812 | { | |
a4da41e1 ER |
1813 | probability = conditional_probability ( |
1814 | default_prob/2, | |
1815 | subtree_prob + default_prob); | |
69107307 AO |
1816 | emit_cmp_and_jump_insns (index, |
1817 | convert_modes | |
1818 | (mode, imode, | |
84217346 | 1819 | expand_normal (node->high), |
69107307 | 1820 | unsignedp), |
d43e0b7d | 1821 | GT, NULL_RTX, mode, unsignedp, |
a4da41e1 ER |
1822 | default_label, |
1823 | probability); | |
1824 | default_prob /= 2; | |
28d81abb RK |
1825 | } |
1826 | ||
a4da41e1 ER |
1827 | emit_case_nodes (index, node->left, default_label, |
1828 | default_prob, index_type); | |
28d81abb RK |
1829 | } |
1830 | else | |
a4da41e1 ER |
1831 | { |
1832 | probability = conditional_probability ( | |
1833 | node->left->subtree_prob, | |
1834 | subtree_prob + default_prob); | |
1835 | /* We cannot process node->left normally | |
1836 | since we haven't ruled out the numbers less than | |
1837 | this node's value. So handle node->left explicitly. */ | |
1838 | do_jump_if_equal (mode, index, | |
1839 | convert_modes | |
1840 | (mode, imode, | |
1841 | expand_normal (node->left->low), | |
1842 | unsignedp), | |
1843 | label_rtx (node->left->code_label), unsignedp, probability); | |
1844 | } | |
28d81abb RK |
1845 | } |
1846 | } | |
1847 | else | |
1848 | { | |
1849 | /* Node is a range. These cases are very similar to those for a single | |
1850 | value, except that we do not start by testing whether this node | |
1851 | is the one to branch to. */ | |
1852 | ||
1853 | if (node->right != 0 && node->left != 0) | |
1854 | { | |
1855 | /* Node has subtrees on both sides. | |
1856 | If the right-hand subtree is bounded, | |
1857 | test for it first, since we can go straight there. | |
1858 | Otherwise, we need to make a branch in the control structure, | |
1859 | then handle the two subtrees. */ | |
1860 | tree test_label = 0; | |
1861 | ||
28d81abb | 1862 | if (node_is_bounded (node->right, index_type)) |
a4da41e1 ER |
1863 | { |
1864 | /* Right hand node is fully bounded so we can eliminate any | |
1865 | testing and branch directly to the target code. */ | |
1866 | probability = conditional_probability ( | |
1867 | node->right->subtree_prob, | |
1868 | subtree_prob + default_prob); | |
1869 | emit_cmp_and_jump_insns (index, | |
1870 | convert_modes | |
1871 | (mode, imode, | |
1872 | expand_normal (node->high), | |
1873 | unsignedp), | |
1874 | GT, NULL_RTX, mode, unsignedp, | |
1875 | label_rtx (node->right->code_label), | |
1876 | probability); | |
1877 | } | |
28d81abb RK |
1878 | else |
1879 | { | |
1880 | /* Right hand node requires testing. | |
1881 | Branch to a label where we will handle it later. */ | |
1882 | ||
5368224f | 1883 | test_label = build_decl (curr_insn_location (), |
c2255bc4 | 1884 | LABEL_DECL, NULL_TREE, NULL_TREE); |
a4da41e1 ER |
1885 | probability = conditional_probability ( |
1886 | node->right->subtree_prob + default_prob/2, | |
1887 | subtree_prob + default_prob); | |
4381f7c2 | 1888 | emit_cmp_and_jump_insns (index, |
69107307 AO |
1889 | convert_modes |
1890 | (mode, imode, | |
84217346 | 1891 | expand_normal (node->high), |
69107307 | 1892 | unsignedp), |
d43e0b7d | 1893 | GT, NULL_RTX, mode, unsignedp, |
a4da41e1 ER |
1894 | label_rtx (test_label), |
1895 | probability); | |
1896 | default_prob /= 2; | |
28d81abb RK |
1897 | } |
1898 | ||
1899 | /* Value belongs to this node or to the left-hand subtree. */ | |
1900 | ||
a4da41e1 ER |
1901 | probability = conditional_probability ( |
1902 | prob, | |
1903 | subtree_prob + default_prob); | |
69107307 AO |
1904 | emit_cmp_and_jump_insns (index, |
1905 | convert_modes | |
1906 | (mode, imode, | |
84217346 | 1907 | expand_normal (node->low), |
69107307 | 1908 | unsignedp), |
d43e0b7d | 1909 | GE, NULL_RTX, mode, unsignedp, |
a4da41e1 ER |
1910 | label_rtx (node->code_label), |
1911 | probability); | |
28d81abb RK |
1912 | |
1913 | /* Handle the left-hand subtree. */ | |
a4da41e1 | 1914 | emit_case_nodes (index, node->left, default_label, default_prob, index_type); |
28d81abb RK |
1915 | |
1916 | /* If right node had to be handled later, do that now. */ | |
1917 | ||
1918 | if (test_label) | |
1919 | { | |
1920 | /* If the left-hand subtree fell through, | |
1921 | don't let it fall into the right-hand subtree. */ | |
b7814a18 RG |
1922 | if (default_label) |
1923 | emit_jump (default_label); | |
28d81abb RK |
1924 | |
1925 | expand_label (test_label); | |
a4da41e1 | 1926 | emit_case_nodes (index, node->right, default_label, default_prob, index_type); |
28d81abb RK |
1927 | } |
1928 | } | |
1929 | ||
1930 | else if (node->right != 0 && node->left == 0) | |
1931 | { | |
1932 | /* Deal with values to the left of this node, | |
1933 | if they are possible. */ | |
1934 | if (!node_has_low_bound (node, index_type)) | |
1935 | { | |
a4da41e1 ER |
1936 | probability = conditional_probability ( |
1937 | default_prob/2, | |
1938 | subtree_prob + default_prob); | |
4381f7c2 | 1939 | emit_cmp_and_jump_insns (index, |
69107307 AO |
1940 | convert_modes |
1941 | (mode, imode, | |
84217346 | 1942 | expand_normal (node->low), |
69107307 | 1943 | unsignedp), |
d43e0b7d | 1944 | LT, NULL_RTX, mode, unsignedp, |
a4da41e1 ER |
1945 | default_label, |
1946 | probability); | |
1947 | default_prob /= 2; | |
28d81abb RK |
1948 | } |
1949 | ||
1950 | /* Value belongs to this node or to the right-hand subtree. */ | |
1951 | ||
a4da41e1 ER |
1952 | probability = conditional_probability ( |
1953 | prob, | |
1954 | subtree_prob + default_prob); | |
69107307 AO |
1955 | emit_cmp_and_jump_insns (index, |
1956 | convert_modes | |
1957 | (mode, imode, | |
84217346 | 1958 | expand_normal (node->high), |
69107307 | 1959 | unsignedp), |
d43e0b7d | 1960 | LE, NULL_RTX, mode, unsignedp, |
a4da41e1 ER |
1961 | label_rtx (node->code_label), |
1962 | probability); | |
28d81abb | 1963 | |
a4da41e1 | 1964 | emit_case_nodes (index, node->right, default_label, default_prob, index_type); |
28d81abb RK |
1965 | } |
1966 | ||
1967 | else if (node->right == 0 && node->left != 0) | |
1968 | { | |
1969 | /* Deal with values to the right of this node, | |
1970 | if they are possible. */ | |
1971 | if (!node_has_high_bound (node, index_type)) | |
1972 | { | |
a4da41e1 ER |
1973 | probability = conditional_probability ( |
1974 | default_prob/2, | |
1975 | subtree_prob + default_prob); | |
4381f7c2 | 1976 | emit_cmp_and_jump_insns (index, |
69107307 AO |
1977 | convert_modes |
1978 | (mode, imode, | |
84217346 | 1979 | expand_normal (node->high), |
69107307 | 1980 | unsignedp), |
d43e0b7d | 1981 | GT, NULL_RTX, mode, unsignedp, |
a4da41e1 ER |
1982 | default_label, |
1983 | probability); | |
1984 | default_prob /= 2; | |
28d81abb RK |
1985 | } |
1986 | ||
1987 | /* Value belongs to this node or to the left-hand subtree. */ | |
1988 | ||
a4da41e1 ER |
1989 | probability = conditional_probability ( |
1990 | prob, | |
1991 | subtree_prob + default_prob); | |
4381f7c2 | 1992 | emit_cmp_and_jump_insns (index, |
69107307 AO |
1993 | convert_modes |
1994 | (mode, imode, | |
84217346 | 1995 | expand_normal (node->low), |
69107307 | 1996 | unsignedp), |
d43e0b7d | 1997 | GE, NULL_RTX, mode, unsignedp, |
a4da41e1 ER |
1998 | label_rtx (node->code_label), |
1999 | probability); | |
28d81abb | 2000 | |
a4da41e1 | 2001 | emit_case_nodes (index, node->left, default_label, default_prob, index_type); |
28d81abb RK |
2002 | } |
2003 | ||
2004 | else | |
2005 | { | |
2006 | /* Node has no children so we check low and high bounds to remove | |
2007 | redundant tests. Only one of the bounds can exist, | |
2008 | since otherwise this node is bounded--a case tested already. */ | |
923cbdc3 JH |
2009 | int high_bound = node_has_high_bound (node, index_type); |
2010 | int low_bound = node_has_low_bound (node, index_type); | |
28d81abb | 2011 | |
923cbdc3 | 2012 | if (!high_bound && low_bound) |
28d81abb | 2013 | { |
a4da41e1 ER |
2014 | probability = conditional_probability ( |
2015 | default_prob, | |
2016 | subtree_prob + default_prob); | |
4381f7c2 | 2017 | emit_cmp_and_jump_insns (index, |
69107307 AO |
2018 | convert_modes |
2019 | (mode, imode, | |
84217346 | 2020 | expand_normal (node->high), |
69107307 | 2021 | unsignedp), |
d43e0b7d | 2022 | GT, NULL_RTX, mode, unsignedp, |
a4da41e1 ER |
2023 | default_label, |
2024 | probability); | |
28d81abb RK |
2025 | } |
2026 | ||
923cbdc3 | 2027 | else if (!low_bound && high_bound) |
28d81abb | 2028 | { |
a4da41e1 ER |
2029 | probability = conditional_probability ( |
2030 | default_prob, | |
2031 | subtree_prob + default_prob); | |
4381f7c2 | 2032 | emit_cmp_and_jump_insns (index, |
69107307 AO |
2033 | convert_modes |
2034 | (mode, imode, | |
84217346 | 2035 | expand_normal (node->low), |
69107307 | 2036 | unsignedp), |
d43e0b7d | 2037 | LT, NULL_RTX, mode, unsignedp, |
a4da41e1 ER |
2038 | default_label, |
2039 | probability); | |
28d81abb | 2040 | } |
923cbdc3 JH |
2041 | else if (!low_bound && !high_bound) |
2042 | { | |
9312aecc | 2043 | /* Widen LOW and HIGH to the same width as INDEX. */ |
ae2bcd98 | 2044 | tree type = lang_hooks.types.type_for_mode (mode, unsignedp); |
9312aecc JDA |
2045 | tree low = build1 (CONVERT_EXPR, type, node->low); |
2046 | tree high = build1 (CONVERT_EXPR, type, node->high); | |
ef89d648 | 2047 | rtx low_rtx, new_index, new_bound; |
9312aecc JDA |
2048 | |
2049 | /* Instead of doing two branches, emit one unsigned branch for | |
2050 | (index-low) > (high-low). */ | |
84217346 | 2051 | low_rtx = expand_expr (low, NULL_RTX, mode, EXPAND_NORMAL); |
ef89d648 ZW |
2052 | new_index = expand_simple_binop (mode, MINUS, index, low_rtx, |
2053 | NULL_RTX, unsignedp, | |
2054 | OPTAB_WIDEN); | |
4845b383 KH |
2055 | new_bound = expand_expr (fold_build2 (MINUS_EXPR, type, |
2056 | high, low), | |
84217346 | 2057 | NULL_RTX, mode, EXPAND_NORMAL); |
786de7eb | 2058 | |
a4da41e1 ER |
2059 | probability = conditional_probability ( |
2060 | default_prob, | |
2061 | subtree_prob + default_prob); | |
9312aecc | 2062 | emit_cmp_and_jump_insns (new_index, new_bound, GT, NULL_RTX, |
a4da41e1 | 2063 | mode, 1, default_label, probability); |
923cbdc3 | 2064 | } |
28d81abb RK |
2065 | |
2066 | emit_jump (label_rtx (node->code_label)); | |
2067 | } | |
2068 | } | |
2069 | } |