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242229bb | 1 | /* A pass for lowering trees to RTL. |
f93089d2 | 2 | Copyright (C) 2004, 2005 Free Software Foundation, Inc. |
242229bb JH |
3 | |
4 | This file is part of GCC. | |
5 | ||
6 | GCC is free software; you can redistribute it and/or modify | |
7 | it under the terms of the GNU General Public License as published by | |
8 | the Free Software Foundation; either version 2, or (at your option) | |
9 | any later version. | |
10 | ||
11 | GCC is distributed in the hope that it will be useful, | |
12 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
13 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
14 | GNU General Public License for more details. | |
15 | ||
16 | You should have received a copy of the GNU General Public License | |
17 | along with GCC; see the file COPYING. If not, write to | |
18 | the Free Software Foundation, 59 Temple Place - Suite 330, | |
19 | Boston, MA 02111-1307, USA. */ | |
20 | ||
21 | #include "config.h" | |
22 | #include "system.h" | |
23 | #include "coretypes.h" | |
24 | #include "tm.h" | |
25 | #include "tree.h" | |
26 | #include "rtl.h" | |
27 | #include "tm_p.h" | |
28 | #include "basic-block.h" | |
29 | #include "function.h" | |
30 | #include "expr.h" | |
31 | #include "langhooks.h" | |
32 | #include "tree-flow.h" | |
33 | #include "timevar.h" | |
34 | #include "tree-dump.h" | |
35 | #include "tree-pass.h" | |
36 | #include "except.h" | |
37 | #include "flags.h" | |
1f6d3a08 RH |
38 | #include "diagnostic.h" |
39 | #include "toplev.h" | |
80c7a9eb | 40 | |
e53de54d JH |
41 | /* Verify that there is exactly single jump instruction since last and attach |
42 | REG_BR_PROB note specifying probability. | |
43 | ??? We really ought to pass the probability down to RTL expanders and let it | |
d7e9e62a KH |
44 | re-distribute it when the conditional expands into multiple conditionals. |
45 | This is however difficult to do. */ | |
e53de54d JH |
46 | static void |
47 | add_reg_br_prob_note (FILE *dump_file, rtx last, int probability) | |
48 | { | |
49 | if (profile_status == PROFILE_ABSENT) | |
50 | return; | |
51 | for (last = NEXT_INSN (last); last && NEXT_INSN (last); last = NEXT_INSN (last)) | |
2ca202e7 | 52 | if (JUMP_P (last)) |
e53de54d JH |
53 | { |
54 | /* It is common to emit condjump-around-jump sequence when we don't know | |
55 | how to reverse the conditional. Special case this. */ | |
56 | if (!any_condjump_p (last) | |
2ca202e7 | 57 | || !JUMP_P (NEXT_INSN (last)) |
e53de54d | 58 | || !simplejump_p (NEXT_INSN (last)) |
2ca202e7 KH |
59 | || !BARRIER_P (NEXT_INSN (NEXT_INSN (last))) |
60 | || !LABEL_P (NEXT_INSN (NEXT_INSN (NEXT_INSN (last)))) | |
e53de54d JH |
61 | || NEXT_INSN (NEXT_INSN (NEXT_INSN (NEXT_INSN (last))))) |
62 | goto failed; | |
41806d92 | 63 | gcc_assert (!find_reg_note (last, REG_BR_PROB, 0)); |
e53de54d JH |
64 | REG_NOTES (last) |
65 | = gen_rtx_EXPR_LIST (REG_BR_PROB, | |
66 | GEN_INT (REG_BR_PROB_BASE - probability), | |
67 | REG_NOTES (last)); | |
68 | return; | |
69 | } | |
2ca202e7 | 70 | if (!last || !JUMP_P (last) || !any_condjump_p (last)) |
41806d92 NS |
71 | goto failed; |
72 | gcc_assert (!find_reg_note (last, REG_BR_PROB, 0)); | |
e53de54d JH |
73 | REG_NOTES (last) |
74 | = gen_rtx_EXPR_LIST (REG_BR_PROB, | |
75 | GEN_INT (probability), REG_NOTES (last)); | |
76 | return; | |
77 | failed: | |
78 | if (dump_file) | |
79 | fprintf (dump_file, "Failed to add probability note\n"); | |
80 | } | |
81 | ||
80c7a9eb | 82 | |
1f6d3a08 RH |
83 | #ifndef LOCAL_ALIGNMENT |
84 | #define LOCAL_ALIGNMENT(TYPE, ALIGNMENT) ALIGNMENT | |
85 | #endif | |
86 | ||
87 | #ifndef STACK_ALIGNMENT_NEEDED | |
88 | #define STACK_ALIGNMENT_NEEDED 1 | |
89 | #endif | |
90 | ||
91 | #ifdef FRAME_GROWS_DOWNWARD | |
92 | # undef FRAME_GROWS_DOWNWARD | |
93 | # define FRAME_GROWS_DOWNWARD 1 | |
94 | #else | |
95 | # define FRAME_GROWS_DOWNWARD 0 | |
96 | #endif | |
97 | ||
98 | ||
99 | /* This structure holds data relevant to one variable that will be | |
100 | placed in a stack slot. */ | |
101 | struct stack_var | |
102 | { | |
103 | /* The Variable. */ | |
104 | tree decl; | |
105 | ||
106 | /* The offset of the variable. During partitioning, this is the | |
107 | offset relative to the partition. After partitioning, this | |
108 | is relative to the stack frame. */ | |
109 | HOST_WIDE_INT offset; | |
110 | ||
111 | /* Initially, the size of the variable. Later, the size of the partition, | |
112 | if this variable becomes it's partition's representative. */ | |
113 | HOST_WIDE_INT size; | |
114 | ||
115 | /* The *byte* alignment required for this variable. Or as, with the | |
116 | size, the alignment for this partition. */ | |
117 | unsigned int alignb; | |
118 | ||
119 | /* The partition representative. */ | |
120 | size_t representative; | |
121 | ||
122 | /* The next stack variable in the partition, or EOC. */ | |
123 | size_t next; | |
124 | }; | |
125 | ||
126 | #define EOC ((size_t)-1) | |
127 | ||
128 | /* We have an array of such objects while deciding allocation. */ | |
129 | static struct stack_var *stack_vars; | |
130 | static size_t stack_vars_alloc; | |
131 | static size_t stack_vars_num; | |
132 | ||
133 | /* An array of indicies such that stack_vars[stack_vars_sorted[i]].size | |
134 | is non-decreasing. */ | |
135 | static size_t *stack_vars_sorted; | |
136 | ||
137 | /* We have an interference graph between such objects. This graph | |
138 | is lower triangular. */ | |
139 | static bool *stack_vars_conflict; | |
140 | static size_t stack_vars_conflict_alloc; | |
141 | ||
142 | /* The phase of the stack frame. This is the known misalignment of | |
143 | virtual_stack_vars_rtx from PREFERRED_STACK_BOUNDARY. That is, | |
144 | (frame_offset+frame_phase) % PREFERRED_STACK_BOUNDARY == 0. */ | |
145 | static int frame_phase; | |
146 | ||
147 | ||
148 | /* Discover the byte alignment to use for DECL. Ignore alignment | |
149 | we can't do with expected alignment of the stack boundary. */ | |
150 | ||
151 | static unsigned int | |
152 | get_decl_align_unit (tree decl) | |
153 | { | |
154 | unsigned int align; | |
155 | ||
156 | align = DECL_ALIGN (decl); | |
157 | align = LOCAL_ALIGNMENT (TREE_TYPE (decl), align); | |
158 | if (align > PREFERRED_STACK_BOUNDARY) | |
159 | align = PREFERRED_STACK_BOUNDARY; | |
160 | if (cfun->stack_alignment_needed < align) | |
161 | cfun->stack_alignment_needed = align; | |
162 | ||
163 | return align / BITS_PER_UNIT; | |
164 | } | |
165 | ||
166 | /* Allocate SIZE bytes at byte alignment ALIGN from the stack frame. | |
167 | Return the frame offset. */ | |
168 | ||
169 | static HOST_WIDE_INT | |
170 | alloc_stack_frame_space (HOST_WIDE_INT size, HOST_WIDE_INT align) | |
171 | { | |
172 | HOST_WIDE_INT offset, new_frame_offset; | |
173 | ||
174 | new_frame_offset = frame_offset; | |
175 | if (FRAME_GROWS_DOWNWARD) | |
176 | { | |
177 | new_frame_offset -= size + frame_phase; | |
178 | new_frame_offset &= -align; | |
179 | new_frame_offset += frame_phase; | |
180 | offset = new_frame_offset; | |
181 | } | |
182 | else | |
183 | { | |
184 | new_frame_offset -= frame_phase; | |
185 | new_frame_offset += align - 1; | |
186 | new_frame_offset &= -align; | |
187 | new_frame_offset += frame_phase; | |
188 | offset = new_frame_offset; | |
189 | new_frame_offset += size; | |
190 | } | |
191 | frame_offset = new_frame_offset; | |
192 | ||
193 | return offset; | |
194 | } | |
195 | ||
196 | /* Accumulate DECL into STACK_VARS. */ | |
197 | ||
198 | static void | |
199 | add_stack_var (tree decl) | |
200 | { | |
201 | if (stack_vars_num >= stack_vars_alloc) | |
202 | { | |
203 | if (stack_vars_alloc) | |
204 | stack_vars_alloc = stack_vars_alloc * 3 / 2; | |
205 | else | |
206 | stack_vars_alloc = 32; | |
207 | stack_vars | |
208 | = XRESIZEVEC (struct stack_var, stack_vars, stack_vars_alloc); | |
209 | } | |
210 | stack_vars[stack_vars_num].decl = decl; | |
211 | stack_vars[stack_vars_num].offset = 0; | |
212 | stack_vars[stack_vars_num].size = tree_low_cst (DECL_SIZE_UNIT (decl), 1); | |
213 | stack_vars[stack_vars_num].alignb = get_decl_align_unit (decl); | |
214 | ||
215 | /* All variables are initially in their own partition. */ | |
216 | stack_vars[stack_vars_num].representative = stack_vars_num; | |
217 | stack_vars[stack_vars_num].next = EOC; | |
218 | ||
219 | /* Ensure that this decl doesn't get put onto the list twice. */ | |
220 | SET_DECL_RTL (decl, pc_rtx); | |
221 | ||
222 | stack_vars_num++; | |
223 | } | |
224 | ||
225 | /* Compute the linear index of a lower-triangular coordinate (I, J). */ | |
226 | ||
227 | static size_t | |
228 | triangular_index (size_t i, size_t j) | |
229 | { | |
230 | if (i < j) | |
231 | { | |
232 | size_t t; | |
233 | t = i, i = j, j = t; | |
234 | } | |
235 | return (i * (i + 1)) / 2 + j; | |
236 | } | |
237 | ||
238 | /* Ensure that STACK_VARS_CONFLICT is large enough for N objects. */ | |
239 | ||
240 | static void | |
241 | resize_stack_vars_conflict (size_t n) | |
242 | { | |
243 | size_t size = triangular_index (n-1, n-1) + 1; | |
244 | ||
245 | if (size <= stack_vars_conflict_alloc) | |
246 | return; | |
247 | ||
248 | stack_vars_conflict = XRESIZEVEC (bool, stack_vars_conflict, size); | |
249 | memset (stack_vars_conflict + stack_vars_conflict_alloc, 0, | |
250 | (size - stack_vars_conflict_alloc) * sizeof (bool)); | |
251 | stack_vars_conflict_alloc = size; | |
252 | } | |
253 | ||
254 | /* Make the decls associated with luid's X and Y conflict. */ | |
255 | ||
256 | static void | |
257 | add_stack_var_conflict (size_t x, size_t y) | |
258 | { | |
259 | size_t index = triangular_index (x, y); | |
260 | gcc_assert (index < stack_vars_conflict_alloc); | |
261 | stack_vars_conflict[index] = true; | |
262 | } | |
263 | ||
264 | /* Check whether the decls associated with luid's X and Y conflict. */ | |
265 | ||
266 | static bool | |
267 | stack_var_conflict_p (size_t x, size_t y) | |
268 | { | |
269 | size_t index = triangular_index (x, y); | |
270 | gcc_assert (index < stack_vars_conflict_alloc); | |
271 | return stack_vars_conflict[index]; | |
272 | } | |
273 | ||
274 | /* A subroutine of expand_used_vars. If two variables X and Y have alias | |
275 | sets that do not conflict, then do add a conflict for these variables | |
276 | in the interference graph. We also have to mind MEM_IN_STRUCT_P and | |
277 | MEM_SCALAR_P. */ | |
278 | ||
279 | static void | |
280 | add_alias_set_conflicts (void) | |
281 | { | |
282 | size_t i, j, n = stack_vars_num; | |
283 | ||
284 | for (i = 0; i < n; ++i) | |
285 | { | |
286 | bool aggr_i = AGGREGATE_TYPE_P (TREE_TYPE (stack_vars[i].decl)); | |
287 | HOST_WIDE_INT set_i = get_alias_set (stack_vars[i].decl); | |
288 | ||
289 | for (j = 0; j < i; ++j) | |
290 | { | |
291 | bool aggr_j = AGGREGATE_TYPE_P (TREE_TYPE (stack_vars[j].decl)); | |
292 | HOST_WIDE_INT set_j = get_alias_set (stack_vars[j].decl); | |
293 | if (aggr_i != aggr_j || !alias_sets_conflict_p (set_i, set_j)) | |
294 | add_stack_var_conflict (i, j); | |
295 | } | |
296 | } | |
297 | } | |
298 | ||
299 | /* A subroutine of partition_stack_vars. A comparison function for qsort, | |
300 | sorting an array of indicies by the size of the object. */ | |
301 | ||
302 | static int | |
303 | stack_var_size_cmp (const void *a, const void *b) | |
304 | { | |
305 | HOST_WIDE_INT sa = stack_vars[*(const size_t *)a].size; | |
306 | HOST_WIDE_INT sb = stack_vars[*(const size_t *)b].size; | |
307 | ||
308 | if (sa < sb) | |
309 | return -1; | |
310 | if (sa > sb) | |
311 | return 1; | |
312 | return 0; | |
313 | } | |
314 | ||
315 | /* A subroutine of partition_stack_vars. The UNION portion of a UNION/FIND | |
316 | partitioning algorithm. Partitions A and B are known to be non-conflicting. | |
317 | Merge them into a single partition A. | |
318 | ||
319 | At the same time, add OFFSET to all variables in partition B. At the end | |
320 | of the partitioning process we've have a nice block easy to lay out within | |
321 | the stack frame. */ | |
322 | ||
323 | static void | |
324 | union_stack_vars (size_t a, size_t b, HOST_WIDE_INT offset) | |
325 | { | |
326 | size_t i, last; | |
327 | ||
328 | /* Update each element of partition B with the given offset, | |
329 | and merge them into partition A. */ | |
330 | for (last = i = b; i != EOC; last = i, i = stack_vars[i].next) | |
331 | { | |
332 | stack_vars[i].offset += offset; | |
333 | stack_vars[i].representative = a; | |
334 | } | |
335 | stack_vars[last].next = stack_vars[a].next; | |
336 | stack_vars[a].next = b; | |
337 | ||
338 | /* Update the required alignment of partition A to account for B. */ | |
339 | if (stack_vars[a].alignb < stack_vars[b].alignb) | |
340 | stack_vars[a].alignb = stack_vars[b].alignb; | |
341 | ||
342 | /* Update the interference graph and merge the conflicts. */ | |
343 | for (last = stack_vars_num, i = 0; i < last; ++i) | |
344 | if (stack_var_conflict_p (b, i)) | |
345 | add_stack_var_conflict (a, i); | |
346 | } | |
347 | ||
348 | /* A subroutine of expand_used_vars. Binpack the variables into | |
349 | partitions constrained by the interference graph. The overall | |
350 | algorithm used is as follows: | |
351 | ||
352 | Sort the objects by size. | |
353 | For each object A { | |
354 | S = size(A) | |
355 | O = 0 | |
356 | loop { | |
357 | Look for the largest non-conflicting object B with size <= S. | |
358 | UNION (A, B) | |
359 | offset(B) = O | |
360 | O += size(B) | |
361 | S -= size(B) | |
362 | } | |
363 | } | |
364 | */ | |
365 | ||
366 | static void | |
367 | partition_stack_vars (void) | |
368 | { | |
369 | size_t si, sj, n = stack_vars_num; | |
370 | ||
371 | stack_vars_sorted = XNEWVEC (size_t, stack_vars_num); | |
372 | for (si = 0; si < n; ++si) | |
373 | stack_vars_sorted[si] = si; | |
374 | ||
375 | if (n == 1) | |
376 | return; | |
377 | ||
378 | qsort (stack_vars_sorted, n, sizeof (size_t), stack_var_size_cmp); | |
379 | ||
380 | /* Special case: detect when all variables conflict, and thus we can't | |
381 | do anything during the partitioning loop. It isn't uncommon (with | |
382 | C code at least) to declare all variables at the top of the function, | |
383 | and if we're not inlining, then all variables will be in the same scope. | |
384 | Take advantage of very fast libc routines for this scan. */ | |
385 | gcc_assert (sizeof(bool) == sizeof(char)); | |
386 | if (memchr (stack_vars_conflict, false, stack_vars_conflict_alloc) == NULL) | |
387 | return; | |
388 | ||
389 | for (si = 0; si < n; ++si) | |
390 | { | |
391 | size_t i = stack_vars_sorted[si]; | |
392 | HOST_WIDE_INT isize = stack_vars[i].size; | |
393 | HOST_WIDE_INT offset = 0; | |
394 | ||
395 | for (sj = si; sj-- > 0; ) | |
396 | { | |
397 | size_t j = stack_vars_sorted[sj]; | |
398 | HOST_WIDE_INT jsize = stack_vars[j].size; | |
399 | unsigned int jalign = stack_vars[j].alignb; | |
400 | ||
401 | /* Ignore objects that aren't partition representatives. */ | |
402 | if (stack_vars[j].representative != j) | |
403 | continue; | |
404 | ||
405 | /* Ignore objects too large for the remaining space. */ | |
406 | if (isize < jsize) | |
407 | continue; | |
408 | ||
409 | /* Ignore conflicting objects. */ | |
410 | if (stack_var_conflict_p (i, j)) | |
411 | continue; | |
412 | ||
413 | /* Refine the remaining space check to include alignment. */ | |
414 | if (offset & (jalign - 1)) | |
415 | { | |
416 | HOST_WIDE_INT toff = offset; | |
417 | toff += jalign - 1; | |
418 | toff &= -(HOST_WIDE_INT)jalign; | |
419 | if (isize - (toff - offset) < jsize) | |
420 | continue; | |
421 | ||
422 | isize -= toff - offset; | |
423 | offset = toff; | |
424 | } | |
425 | ||
426 | /* UNION the objects, placing J at OFFSET. */ | |
427 | union_stack_vars (i, j, offset); | |
428 | ||
429 | isize -= jsize; | |
430 | if (isize == 0) | |
431 | break; | |
432 | } | |
433 | } | |
434 | } | |
435 | ||
436 | /* A debugging aid for expand_used_vars. Dump the generated partitions. */ | |
437 | ||
438 | static void | |
439 | dump_stack_var_partition (void) | |
440 | { | |
441 | size_t si, i, j, n = stack_vars_num; | |
442 | ||
443 | for (si = 0; si < n; ++si) | |
444 | { | |
445 | i = stack_vars_sorted[si]; | |
446 | ||
447 | /* Skip variables that aren't partition representatives, for now. */ | |
448 | if (stack_vars[i].representative != i) | |
449 | continue; | |
450 | ||
451 | fprintf (dump_file, "Partition %lu: size " HOST_WIDE_INT_PRINT_DEC | |
452 | " align %u\n", (unsigned long) i, stack_vars[i].size, | |
453 | stack_vars[i].alignb); | |
454 | ||
455 | for (j = i; j != EOC; j = stack_vars[j].next) | |
456 | { | |
457 | fputc ('\t', dump_file); | |
458 | print_generic_expr (dump_file, stack_vars[j].decl, dump_flags); | |
459 | fprintf (dump_file, ", offset " HOST_WIDE_INT_PRINT_DEC "\n", | |
460 | stack_vars[i].offset); | |
461 | } | |
462 | } | |
463 | } | |
464 | ||
465 | /* Assign rtl to DECL at frame offset OFFSET. */ | |
466 | ||
467 | static void | |
468 | expand_one_stack_var_at (tree decl, HOST_WIDE_INT offset) | |
469 | { | |
470 | HOST_WIDE_INT align; | |
471 | rtx x; | |
472 | ||
473 | /* If this fails, we've overflowed the stack frame. Error nicely? */ | |
474 | gcc_assert (offset == trunc_int_for_mode (offset, Pmode)); | |
475 | ||
476 | x = plus_constant (virtual_stack_vars_rtx, offset); | |
477 | x = gen_rtx_MEM (DECL_MODE (decl), x); | |
478 | ||
479 | /* Set alignment we actually gave this decl. */ | |
480 | offset -= frame_phase; | |
481 | align = offset & -offset; | |
482 | align *= BITS_PER_UNIT; | |
483 | if (align > STACK_BOUNDARY || align == 0) | |
484 | align = STACK_BOUNDARY; | |
485 | DECL_ALIGN (decl) = align; | |
486 | DECL_USER_ALIGN (decl) = 0; | |
487 | ||
488 | set_mem_attributes (x, decl, true); | |
489 | SET_DECL_RTL (decl, x); | |
490 | } | |
491 | ||
492 | /* A subroutine of expand_used_vars. Give each partition representative | |
493 | a unique location within the stack frame. Update each partition member | |
494 | with that location. */ | |
495 | ||
496 | static void | |
497 | expand_stack_vars (void) | |
498 | { | |
499 | size_t si, i, j, n = stack_vars_num; | |
500 | ||
501 | for (si = 0; si < n; ++si) | |
502 | { | |
503 | HOST_WIDE_INT offset; | |
504 | ||
505 | i = stack_vars_sorted[si]; | |
506 | ||
507 | /* Skip variables that aren't partition representatives, for now. */ | |
508 | if (stack_vars[i].representative != i) | |
509 | continue; | |
510 | ||
511 | offset = alloc_stack_frame_space (stack_vars[i].size, | |
512 | stack_vars[i].alignb); | |
513 | ||
514 | /* Create rtl for each variable based on their location within the | |
515 | partition. */ | |
516 | for (j = i; j != EOC; j = stack_vars[j].next) | |
517 | expand_one_stack_var_at (stack_vars[j].decl, | |
518 | stack_vars[j].offset + offset); | |
519 | } | |
520 | } | |
521 | ||
522 | /* A subroutine of expand_one_var. Called to immediately assign rtl | |
523 | to a variable to be allocated in the stack frame. */ | |
524 | ||
525 | static void | |
526 | expand_one_stack_var (tree var) | |
527 | { | |
528 | HOST_WIDE_INT size, offset, align; | |
529 | ||
530 | size = tree_low_cst (DECL_SIZE_UNIT (var), 1); | |
531 | align = get_decl_align_unit (var); | |
532 | offset = alloc_stack_frame_space (size, align); | |
533 | ||
534 | expand_one_stack_var_at (var, offset); | |
535 | } | |
536 | ||
537 | /* A subroutine of expand_one_var. Called to assign rtl | |
538 | to a TREE_STATIC VAR_DECL. */ | |
539 | ||
540 | static void | |
541 | expand_one_static_var (tree var) | |
542 | { | |
543 | /* If this is an inlined copy of a static local variable, | |
544 | look up the original. */ | |
545 | var = DECL_ORIGIN (var); | |
546 | ||
547 | /* If we've already processed this variable because of that, do nothing. */ | |
548 | if (TREE_ASM_WRITTEN (var)) | |
549 | return; | |
550 | ||
551 | /* Give the front end a chance to do whatever. In practice, this is | |
552 | resolving duplicate names for IMA in C. */ | |
553 | if (lang_hooks.expand_decl (var)) | |
554 | return; | |
555 | ||
556 | /* Otherwise, just emit the variable. */ | |
557 | rest_of_decl_compilation (var, 0, 0); | |
558 | } | |
559 | ||
560 | /* A subroutine of expand_one_var. Called to assign rtl to a VAR_DECL | |
561 | that will reside in a hard register. */ | |
562 | ||
563 | static void | |
564 | expand_one_hard_reg_var (tree var) | |
565 | { | |
566 | rest_of_decl_compilation (var, 0, 0); | |
567 | } | |
568 | ||
569 | /* A subroutine of expand_one_var. Called to assign rtl to a VAR_DECL | |
570 | that will reside in a pseudo register. */ | |
571 | ||
572 | static void | |
573 | expand_one_register_var (tree var) | |
574 | { | |
575 | tree type = TREE_TYPE (var); | |
576 | int unsignedp = TYPE_UNSIGNED (type); | |
577 | enum machine_mode reg_mode | |
578 | = promote_mode (type, DECL_MODE (var), &unsignedp, 0); | |
579 | rtx x = gen_reg_rtx (reg_mode); | |
580 | ||
581 | SET_DECL_RTL (var, x); | |
582 | ||
583 | /* Note if the object is a user variable. */ | |
584 | if (!DECL_ARTIFICIAL (var)) | |
585 | { | |
586 | mark_user_reg (x); | |
587 | ||
588 | /* Trust user variables which have a pointer type to really | |
589 | be pointers. Do not trust compiler generated temporaries | |
590 | as our type system is totally busted as it relates to | |
591 | pointer arithmetic which translates into lots of compiler | |
592 | generated objects with pointer types, but which are not really | |
593 | pointers. */ | |
594 | if (POINTER_TYPE_P (type)) | |
595 | mark_reg_pointer (x, TYPE_ALIGN (TREE_TYPE (TREE_TYPE (var)))); | |
596 | } | |
597 | } | |
598 | ||
599 | /* A subroutine of expand_one_var. Called to assign rtl to a VAR_DECL that | |
600 | has some associated error, e.g. it's type is error-mark. We just need | |
601 | to pick something that won't crash the rest of the compiler. */ | |
602 | ||
603 | static void | |
604 | expand_one_error_var (tree var) | |
605 | { | |
606 | enum machine_mode mode = DECL_MODE (var); | |
607 | rtx x; | |
608 | ||
609 | if (mode == BLKmode) | |
610 | x = gen_rtx_MEM (BLKmode, const0_rtx); | |
611 | else if (mode == VOIDmode) | |
612 | x = const0_rtx; | |
613 | else | |
614 | x = gen_reg_rtx (mode); | |
615 | ||
616 | SET_DECL_RTL (var, x); | |
617 | } | |
618 | ||
619 | /* A subroutine of expand_one_var. VAR is a variable that will be | |
620 | allocated to the local stack frame. Return true if we wish to | |
621 | add VAR to STACK_VARS so that it will be coalesced with other | |
622 | variables. Return false to allocate VAR immediately. | |
623 | ||
624 | This function is used to reduce the number of variables considered | |
625 | for coalescing, which reduces the size of the quadratic problem. */ | |
626 | ||
627 | static bool | |
628 | defer_stack_allocation (tree var, bool toplevel) | |
629 | { | |
630 | /* Variables in the outermost scope automatically conflict with | |
631 | every other variable. The only reason to want to defer them | |
632 | at all is that, after sorting, we can more efficiently pack | |
633 | small variables in the stack frame. Continue to defer at -O2. */ | |
634 | if (toplevel && optimize < 2) | |
635 | return false; | |
636 | ||
637 | /* Without optimization, *most* variables are allocated from the | |
638 | stack, which makes the quadratic problem large exactly when we | |
639 | want compilation to proceed as quickly as possible. On the | |
640 | other hand, we don't want the function's stack frame size to | |
641 | get completely out of hand. So we avoid adding scalars and | |
642 | "small" aggregates to the list at all. */ | |
643 | if (optimize == 0 && tree_low_cst (DECL_SIZE_UNIT (var), 1) < 32) | |
644 | return false; | |
645 | ||
646 | return true; | |
647 | } | |
648 | ||
649 | /* A subroutine of expand_used_vars. Expand one variable according to | |
2a7e31df | 650 | its flavor. Variables to be placed on the stack are not actually |
1f6d3a08 RH |
651 | expanded yet, merely recorded. */ |
652 | ||
653 | static void | |
654 | expand_one_var (tree var, bool toplevel) | |
655 | { | |
656 | if (TREE_CODE (var) != VAR_DECL) | |
657 | lang_hooks.expand_decl (var); | |
658 | else if (DECL_EXTERNAL (var)) | |
659 | ; | |
660 | else if (DECL_VALUE_EXPR (var)) | |
661 | ; | |
662 | else if (TREE_STATIC (var)) | |
663 | expand_one_static_var (var); | |
664 | else if (DECL_RTL_SET_P (var)) | |
665 | ; | |
666 | else if (TREE_TYPE (var) == error_mark_node) | |
667 | expand_one_error_var (var); | |
668 | else if (DECL_HARD_REGISTER (var)) | |
669 | expand_one_hard_reg_var (var); | |
670 | else if (use_register_for_decl (var)) | |
671 | expand_one_register_var (var); | |
672 | else if (defer_stack_allocation (var, toplevel)) | |
673 | add_stack_var (var); | |
674 | else | |
675 | expand_one_stack_var (var); | |
676 | } | |
677 | ||
678 | /* A subroutine of expand_used_vars. Walk down through the BLOCK tree | |
679 | expanding variables. Those variables that can be put into registers | |
680 | are allocated pseudos; those that can't are put on the stack. | |
681 | ||
682 | TOPLEVEL is true if this is the outermost BLOCK. */ | |
683 | ||
684 | static void | |
685 | expand_used_vars_for_block (tree block, bool toplevel) | |
686 | { | |
687 | size_t i, j, old_sv_num, this_sv_num, new_sv_num; | |
688 | tree t; | |
689 | ||
690 | old_sv_num = toplevel ? 0 : stack_vars_num; | |
691 | ||
692 | /* Expand all variables at this level. */ | |
693 | for (t = BLOCK_VARS (block); t ; t = TREE_CHAIN (t)) | |
694 | if (TREE_USED (t)) | |
695 | expand_one_var (t, toplevel); | |
696 | ||
697 | this_sv_num = stack_vars_num; | |
698 | ||
699 | /* Expand all variables at containing levels. */ | |
700 | for (t = BLOCK_SUBBLOCKS (block); t ; t = BLOCK_CHAIN (t)) | |
701 | expand_used_vars_for_block (t, false); | |
702 | ||
703 | /* Since we do not track exact variable lifetimes (which is not even | |
704 | possible for varibles whose address escapes), we mirror the block | |
705 | tree in the interference graph. Here we cause all variables at this | |
706 | level, and all sublevels, to conflict. Do make certain that a | |
707 | variable conflicts with itself. */ | |
708 | if (old_sv_num < this_sv_num) | |
709 | { | |
710 | new_sv_num = stack_vars_num; | |
711 | resize_stack_vars_conflict (new_sv_num); | |
712 | ||
713 | for (i = old_sv_num; i < new_sv_num; ++i) | |
f4a6d54e RH |
714 | for (j = i < this_sv_num ? i+1 : this_sv_num; j-- > old_sv_num ;) |
715 | add_stack_var_conflict (i, j); | |
1f6d3a08 RH |
716 | } |
717 | } | |
718 | ||
719 | /* A subroutine of expand_used_vars. Walk down through the BLOCK tree | |
720 | and clear TREE_USED on all local variables. */ | |
721 | ||
722 | static void | |
723 | clear_tree_used (tree block) | |
724 | { | |
725 | tree t; | |
726 | ||
727 | for (t = BLOCK_VARS (block); t ; t = TREE_CHAIN (t)) | |
728 | /* if (!TREE_STATIC (t) && !DECL_EXTERNAL (t)) */ | |
729 | TREE_USED (t) = 0; | |
730 | ||
731 | for (t = BLOCK_SUBBLOCKS (block); t ; t = BLOCK_CHAIN (t)) | |
732 | clear_tree_used (t); | |
733 | } | |
734 | ||
735 | /* Expand all variables used in the function. */ | |
727a31fa RH |
736 | |
737 | static void | |
738 | expand_used_vars (void) | |
739 | { | |
1f6d3a08 | 740 | tree t, outer_block = DECL_INITIAL (current_function_decl); |
727a31fa | 741 | |
1f6d3a08 RH |
742 | /* Compute the phase of the stack frame for this function. */ |
743 | { | |
744 | int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT; | |
745 | int off = STARTING_FRAME_OFFSET % align; | |
746 | frame_phase = off ? align - off : 0; | |
747 | } | |
727a31fa | 748 | |
1f6d3a08 RH |
749 | /* Set TREE_USED on all variables in the unexpanded_var_list. */ |
750 | for (t = cfun->unexpanded_var_list; t; t = TREE_CHAIN (t)) | |
751 | TREE_USED (TREE_VALUE (t)) = 1; | |
727a31fa | 752 | |
1f6d3a08 RH |
753 | /* Clear TREE_USED on all variables associated with a block scope. */ |
754 | clear_tree_used (outer_block); | |
755 | ||
756 | /* At this point all variables on the unexpanded_var_list with TREE_USED | |
757 | set are not associated with any block scope. Lay them out. */ | |
758 | for (t = cfun->unexpanded_var_list; t; t = TREE_CHAIN (t)) | |
759 | { | |
760 | tree var = TREE_VALUE (t); | |
761 | bool expand_now = false; | |
762 | ||
763 | /* We didn't set a block for static or extern because it's hard | |
764 | to tell the difference between a global variable (re)declared | |
765 | in a local scope, and one that's really declared there to | |
766 | begin with. And it doesn't really matter much, since we're | |
767 | not giving them stack space. Expand them now. */ | |
768 | if (TREE_STATIC (var) || DECL_EXTERNAL (var)) | |
769 | expand_now = true; | |
770 | ||
771 | /* Any variable that could have been hoisted into an SSA_NAME | |
772 | will have been propagated anywhere the optimizers chose, | |
773 | i.e. not confined to their original block. Allocate them | |
774 | as if they were defined in the outermost scope. */ | |
775 | else if (is_gimple_reg (var)) | |
776 | expand_now = true; | |
777 | ||
778 | /* If the variable is not associated with any block, then it | |
779 | was created by the optimizers, and could be live anywhere | |
780 | in the function. */ | |
781 | else if (TREE_USED (var)) | |
782 | expand_now = true; | |
783 | ||
784 | /* Finally, mark all variables on the list as used. We'll use | |
785 | this in a moment when we expand those associated with scopes. */ | |
786 | TREE_USED (var) = 1; | |
787 | ||
788 | if (expand_now) | |
789 | expand_one_var (var, true); | |
790 | } | |
727a31fa | 791 | cfun->unexpanded_var_list = NULL_TREE; |
1f6d3a08 RH |
792 | |
793 | /* At this point, all variables within the block tree with TREE_USED | |
794 | set are actually used by the optimized function. Lay them out. */ | |
795 | expand_used_vars_for_block (outer_block, true); | |
796 | ||
797 | if (stack_vars_num > 0) | |
798 | { | |
799 | /* Due to the way alias sets work, no variables with non-conflicting | |
800 | alias sets may be assigned the same address. Add conflicts to | |
801 | reflect this. */ | |
802 | add_alias_set_conflicts (); | |
803 | ||
804 | /* Now that we have collected all stack variables, and have computed a | |
805 | minimal interference graph, attempt to save some stack space. */ | |
806 | partition_stack_vars (); | |
807 | if (dump_file) | |
808 | dump_stack_var_partition (); | |
809 | ||
810 | /* Assign rtl to each variable based on these partitions. */ | |
811 | expand_stack_vars (); | |
812 | ||
813 | /* Free up stack variable graph data. */ | |
814 | XDELETEVEC (stack_vars); | |
815 | XDELETEVEC (stack_vars_sorted); | |
816 | XDELETEVEC (stack_vars_conflict); | |
817 | stack_vars = NULL; | |
818 | stack_vars_alloc = stack_vars_num = 0; | |
819 | stack_vars_conflict = NULL; | |
820 | stack_vars_conflict_alloc = 0; | |
821 | } | |
822 | ||
823 | /* If the target requires that FRAME_OFFSET be aligned, do it. */ | |
824 | if (STACK_ALIGNMENT_NEEDED) | |
825 | { | |
826 | HOST_WIDE_INT align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT; | |
827 | if (!FRAME_GROWS_DOWNWARD) | |
828 | frame_offset += align - 1; | |
829 | frame_offset &= -align; | |
830 | } | |
727a31fa RH |
831 | } |
832 | ||
833 | ||
b7211528 SB |
834 | /* If we need to produce a detailed dump, print the tree representation |
835 | for STMT to the dump file. SINCE is the last RTX after which the RTL | |
836 | generated for STMT should have been appended. */ | |
837 | ||
838 | static void | |
839 | maybe_dump_rtl_for_tree_stmt (tree stmt, rtx since) | |
840 | { | |
841 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
842 | { | |
843 | fprintf (dump_file, "\n;; "); | |
844 | print_generic_expr (dump_file, stmt, TDF_SLIM); | |
845 | fprintf (dump_file, "\n"); | |
846 | ||
847 | print_rtl (dump_file, since ? NEXT_INSN (since) : since); | |
848 | } | |
849 | } | |
850 | ||
80c7a9eb RH |
851 | /* A subroutine of expand_gimple_basic_block. Expand one COND_EXPR. |
852 | Returns a new basic block if we've terminated the current basic | |
853 | block and created a new one. */ | |
854 | ||
855 | static basic_block | |
856 | expand_gimple_cond_expr (basic_block bb, tree stmt) | |
857 | { | |
858 | basic_block new_bb, dest; | |
859 | edge new_edge; | |
860 | edge true_edge; | |
861 | edge false_edge; | |
862 | tree pred = COND_EXPR_COND (stmt); | |
863 | tree then_exp = COND_EXPR_THEN (stmt); | |
864 | tree else_exp = COND_EXPR_ELSE (stmt); | |
b7211528 SB |
865 | rtx last2, last; |
866 | ||
867 | last2 = last = get_last_insn (); | |
80c7a9eb RH |
868 | |
869 | extract_true_false_edges_from_block (bb, &true_edge, &false_edge); | |
870 | if (EXPR_LOCUS (stmt)) | |
871 | { | |
872 | emit_line_note (*(EXPR_LOCUS (stmt))); | |
873 | record_block_change (TREE_BLOCK (stmt)); | |
874 | } | |
875 | ||
876 | /* These flags have no purpose in RTL land. */ | |
877 | true_edge->flags &= ~EDGE_TRUE_VALUE; | |
878 | false_edge->flags &= ~EDGE_FALSE_VALUE; | |
879 | ||
880 | /* We can either have a pure conditional jump with one fallthru edge or | |
881 | two-way jump that needs to be decomposed into two basic blocks. */ | |
882 | if (TREE_CODE (then_exp) == GOTO_EXPR && IS_EMPTY_STMT (else_exp)) | |
883 | { | |
884 | jumpif (pred, label_rtx (GOTO_DESTINATION (then_exp))); | |
e53de54d | 885 | add_reg_br_prob_note (dump_file, last, true_edge->probability); |
b7211528 | 886 | maybe_dump_rtl_for_tree_stmt (stmt, last); |
ac8245fa AP |
887 | if (EXPR_LOCUS (then_exp)) |
888 | emit_line_note (*(EXPR_LOCUS (then_exp))); | |
80c7a9eb RH |
889 | return NULL; |
890 | } | |
891 | if (TREE_CODE (else_exp) == GOTO_EXPR && IS_EMPTY_STMT (then_exp)) | |
892 | { | |
893 | jumpifnot (pred, label_rtx (GOTO_DESTINATION (else_exp))); | |
e53de54d | 894 | add_reg_br_prob_note (dump_file, last, false_edge->probability); |
b7211528 | 895 | maybe_dump_rtl_for_tree_stmt (stmt, last); |
ac8245fa AP |
896 | if (EXPR_LOCUS (else_exp)) |
897 | emit_line_note (*(EXPR_LOCUS (else_exp))); | |
80c7a9eb RH |
898 | return NULL; |
899 | } | |
341c100f NS |
900 | gcc_assert (TREE_CODE (then_exp) == GOTO_EXPR |
901 | && TREE_CODE (else_exp) == GOTO_EXPR); | |
80c7a9eb RH |
902 | |
903 | jumpif (pred, label_rtx (GOTO_DESTINATION (then_exp))); | |
e53de54d | 904 | add_reg_br_prob_note (dump_file, last, true_edge->probability); |
80c7a9eb RH |
905 | last = get_last_insn (); |
906 | expand_expr (else_exp, const0_rtx, VOIDmode, 0); | |
907 | ||
908 | BB_END (bb) = last; | |
909 | if (BARRIER_P (BB_END (bb))) | |
910 | BB_END (bb) = PREV_INSN (BB_END (bb)); | |
911 | update_bb_for_insn (bb); | |
912 | ||
913 | new_bb = create_basic_block (NEXT_INSN (last), get_last_insn (), bb); | |
914 | dest = false_edge->dest; | |
915 | redirect_edge_succ (false_edge, new_bb); | |
916 | false_edge->flags |= EDGE_FALLTHRU; | |
917 | new_bb->count = false_edge->count; | |
918 | new_bb->frequency = EDGE_FREQUENCY (false_edge); | |
919 | new_edge = make_edge (new_bb, dest, 0); | |
920 | new_edge->probability = REG_BR_PROB_BASE; | |
921 | new_edge->count = new_bb->count; | |
922 | if (BARRIER_P (BB_END (new_bb))) | |
923 | BB_END (new_bb) = PREV_INSN (BB_END (new_bb)); | |
924 | update_bb_for_insn (new_bb); | |
925 | ||
b7211528 | 926 | maybe_dump_rtl_for_tree_stmt (stmt, last2); |
ac8245fa AP |
927 | |
928 | if (EXPR_LOCUS (else_exp)) | |
929 | emit_line_note (*(EXPR_LOCUS (else_exp))); | |
80c7a9eb RH |
930 | |
931 | return new_bb; | |
932 | } | |
933 | ||
934 | /* A subroutine of expand_gimple_basic_block. Expand one CALL_EXPR | |
224e770b RH |
935 | that has CALL_EXPR_TAILCALL set. Returns non-null if we actually |
936 | generated a tail call (something that might be denied by the ABI | |
cea49550 RH |
937 | rules governing the call; see calls.c). |
938 | ||
939 | Sets CAN_FALLTHRU if we generated a *conditional* tail call, and | |
940 | can still reach the rest of BB. The case here is __builtin_sqrt, | |
941 | where the NaN result goes through the external function (with a | |
942 | tailcall) and the normal result happens via a sqrt instruction. */ | |
80c7a9eb RH |
943 | |
944 | static basic_block | |
cea49550 | 945 | expand_gimple_tailcall (basic_block bb, tree stmt, bool *can_fallthru) |
80c7a9eb | 946 | { |
b7211528 | 947 | rtx last2, last; |
224e770b | 948 | edge e; |
628f6a4e | 949 | edge_iterator ei; |
224e770b RH |
950 | int probability; |
951 | gcov_type count; | |
80c7a9eb | 952 | |
b7211528 SB |
953 | last2 = last = get_last_insn (); |
954 | ||
80c7a9eb RH |
955 | expand_expr_stmt (stmt); |
956 | ||
957 | for (last = NEXT_INSN (last); last; last = NEXT_INSN (last)) | |
224e770b RH |
958 | if (CALL_P (last) && SIBLING_CALL_P (last)) |
959 | goto found; | |
80c7a9eb | 960 | |
7315a949 | 961 | maybe_dump_rtl_for_tree_stmt (stmt, last2); |
b7211528 | 962 | |
cea49550 | 963 | *can_fallthru = true; |
224e770b | 964 | return NULL; |
80c7a9eb | 965 | |
224e770b RH |
966 | found: |
967 | /* ??? Wouldn't it be better to just reset any pending stack adjust? | |
968 | Any instructions emitted here are about to be deleted. */ | |
969 | do_pending_stack_adjust (); | |
970 | ||
971 | /* Remove any non-eh, non-abnormal edges that don't go to exit. */ | |
972 | /* ??? I.e. the fallthrough edge. HOWEVER! If there were to be | |
973 | EH or abnormal edges, we shouldn't have created a tail call in | |
974 | the first place. So it seems to me we should just be removing | |
975 | all edges here, or redirecting the existing fallthru edge to | |
976 | the exit block. */ | |
977 | ||
224e770b RH |
978 | probability = 0; |
979 | count = 0; | |
224e770b | 980 | |
628f6a4e BE |
981 | for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); ) |
982 | { | |
224e770b RH |
983 | if (!(e->flags & (EDGE_ABNORMAL | EDGE_EH))) |
984 | { | |
985 | if (e->dest != EXIT_BLOCK_PTR) | |
80c7a9eb | 986 | { |
224e770b RH |
987 | e->dest->count -= e->count; |
988 | e->dest->frequency -= EDGE_FREQUENCY (e); | |
989 | if (e->dest->count < 0) | |
990 | e->dest->count = 0; | |
991 | if (e->dest->frequency < 0) | |
992 | e->dest->frequency = 0; | |
80c7a9eb | 993 | } |
224e770b RH |
994 | count += e->count; |
995 | probability += e->probability; | |
996 | remove_edge (e); | |
80c7a9eb | 997 | } |
628f6a4e BE |
998 | else |
999 | ei_next (&ei); | |
80c7a9eb RH |
1000 | } |
1001 | ||
224e770b RH |
1002 | /* This is somewhat ugly: the call_expr expander often emits instructions |
1003 | after the sibcall (to perform the function return). These confuse the | |
12eff7b7 | 1004 | find_many_sub_basic_blocks code, so we need to get rid of these. */ |
224e770b | 1005 | last = NEXT_INSN (last); |
341c100f | 1006 | gcc_assert (BARRIER_P (last)); |
cea49550 RH |
1007 | |
1008 | *can_fallthru = false; | |
224e770b RH |
1009 | while (NEXT_INSN (last)) |
1010 | { | |
1011 | /* For instance an sqrt builtin expander expands if with | |
1012 | sibcall in the then and label for `else`. */ | |
1013 | if (LABEL_P (NEXT_INSN (last))) | |
cea49550 RH |
1014 | { |
1015 | *can_fallthru = true; | |
1016 | break; | |
1017 | } | |
224e770b RH |
1018 | delete_insn (NEXT_INSN (last)); |
1019 | } | |
1020 | ||
1021 | e = make_edge (bb, EXIT_BLOCK_PTR, EDGE_ABNORMAL | EDGE_SIBCALL); | |
1022 | e->probability += probability; | |
1023 | e->count += count; | |
1024 | BB_END (bb) = last; | |
1025 | update_bb_for_insn (bb); | |
1026 | ||
1027 | if (NEXT_INSN (last)) | |
1028 | { | |
1029 | bb = create_basic_block (NEXT_INSN (last), get_last_insn (), bb); | |
1030 | ||
1031 | last = BB_END (bb); | |
1032 | if (BARRIER_P (last)) | |
1033 | BB_END (bb) = PREV_INSN (last); | |
1034 | } | |
1035 | ||
b7211528 SB |
1036 | maybe_dump_rtl_for_tree_stmt (stmt, last2); |
1037 | ||
224e770b | 1038 | return bb; |
80c7a9eb RH |
1039 | } |
1040 | ||
242229bb JH |
1041 | /* Expand basic block BB from GIMPLE trees to RTL. */ |
1042 | ||
1043 | static basic_block | |
80c7a9eb | 1044 | expand_gimple_basic_block (basic_block bb, FILE * dump_file) |
242229bb JH |
1045 | { |
1046 | block_stmt_iterator bsi = bsi_start (bb); | |
1047 | tree stmt = NULL; | |
1048 | rtx note, last; | |
1049 | edge e; | |
628f6a4e | 1050 | edge_iterator ei; |
242229bb JH |
1051 | |
1052 | if (dump_file) | |
1053 | { | |
b7211528 SB |
1054 | fprintf (dump_file, |
1055 | "\n;; Generating RTL for tree basic block %d\n", | |
1056 | bb->index); | |
242229bb JH |
1057 | } |
1058 | ||
1059 | if (!bsi_end_p (bsi)) | |
1060 | stmt = bsi_stmt (bsi); | |
1061 | ||
1062 | if (stmt && TREE_CODE (stmt) == LABEL_EXPR) | |
1063 | { | |
1064 | last = get_last_insn (); | |
1065 | ||
4dfa0342 | 1066 | expand_expr_stmt (stmt); |
242229bb | 1067 | |
caf93cb0 | 1068 | /* Java emits line number notes in the top of labels. |
242229bb JH |
1069 | ??? Make this go away once line number notes are obsoleted. */ |
1070 | BB_HEAD (bb) = NEXT_INSN (last); | |
4b4bf941 | 1071 | if (NOTE_P (BB_HEAD (bb))) |
242229bb JH |
1072 | BB_HEAD (bb) = NEXT_INSN (BB_HEAD (bb)); |
1073 | bsi_next (&bsi); | |
1074 | note = emit_note_after (NOTE_INSN_BASIC_BLOCK, BB_HEAD (bb)); | |
b7211528 SB |
1075 | |
1076 | maybe_dump_rtl_for_tree_stmt (stmt, last); | |
242229bb JH |
1077 | } |
1078 | else | |
1079 | note = BB_HEAD (bb) = emit_note (NOTE_INSN_BASIC_BLOCK); | |
1080 | ||
1081 | NOTE_BASIC_BLOCK (note) = bb; | |
1082 | ||
628f6a4e | 1083 | for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); ) |
242229bb | 1084 | { |
242229bb JH |
1085 | /* Clear EDGE_EXECUTABLE. This flag is never used in the backend. */ |
1086 | e->flags &= ~EDGE_EXECUTABLE; | |
1087 | ||
1088 | /* At the moment not all abnormal edges match the RTL representation. | |
12eff7b7 | 1089 | It is safe to remove them here as find_many_sub_basic_blocks will |
242229bb JH |
1090 | rediscover them. In the future we should get this fixed properly. */ |
1091 | if (e->flags & EDGE_ABNORMAL) | |
1092 | remove_edge (e); | |
628f6a4e BE |
1093 | else |
1094 | ei_next (&ei); | |
242229bb JH |
1095 | } |
1096 | ||
1097 | for (; !bsi_end_p (bsi); bsi_next (&bsi)) | |
1098 | { | |
1099 | tree stmt = bsi_stmt (bsi); | |
cea49550 | 1100 | basic_block new_bb; |
242229bb JH |
1101 | |
1102 | if (!stmt) | |
1103 | continue; | |
1104 | ||
1105 | /* Expand this statement, then evaluate the resulting RTL and | |
1106 | fixup the CFG accordingly. */ | |
80c7a9eb | 1107 | if (TREE_CODE (stmt) == COND_EXPR) |
cea49550 RH |
1108 | { |
1109 | new_bb = expand_gimple_cond_expr (bb, stmt); | |
1110 | if (new_bb) | |
1111 | return new_bb; | |
1112 | } | |
80c7a9eb | 1113 | else |
242229bb | 1114 | { |
80c7a9eb RH |
1115 | tree call = get_call_expr_in (stmt); |
1116 | if (call && CALL_EXPR_TAILCALL (call)) | |
cea49550 RH |
1117 | { |
1118 | bool can_fallthru; | |
1119 | new_bb = expand_gimple_tailcall (bb, stmt, &can_fallthru); | |
1120 | if (new_bb) | |
1121 | { | |
1122 | if (can_fallthru) | |
1123 | bb = new_bb; | |
1124 | else | |
1125 | return new_bb; | |
1126 | } | |
1127 | } | |
80c7a9eb | 1128 | else |
b7211528 SB |
1129 | { |
1130 | last = get_last_insn (); | |
1131 | expand_expr_stmt (stmt); | |
1132 | maybe_dump_rtl_for_tree_stmt (stmt, last); | |
1133 | } | |
242229bb JH |
1134 | } |
1135 | } | |
1136 | ||
1137 | do_pending_stack_adjust (); | |
1138 | ||
3f117656 | 1139 | /* Find the block tail. The last insn in the block is the insn |
242229bb JH |
1140 | before a barrier and/or table jump insn. */ |
1141 | last = get_last_insn (); | |
4b4bf941 | 1142 | if (BARRIER_P (last)) |
242229bb JH |
1143 | last = PREV_INSN (last); |
1144 | if (JUMP_TABLE_DATA_P (last)) | |
1145 | last = PREV_INSN (PREV_INSN (last)); | |
1146 | BB_END (bb) = last; | |
caf93cb0 | 1147 | |
242229bb | 1148 | update_bb_for_insn (bb); |
80c7a9eb | 1149 | |
242229bb JH |
1150 | return bb; |
1151 | } | |
1152 | ||
1153 | ||
1154 | /* Create a basic block for initialization code. */ | |
1155 | ||
1156 | static basic_block | |
1157 | construct_init_block (void) | |
1158 | { | |
1159 | basic_block init_block, first_block; | |
275a4187 | 1160 | edge e = NULL, e2; |
628f6a4e | 1161 | edge_iterator ei; |
275a4187 | 1162 | |
628f6a4e | 1163 | FOR_EACH_EDGE (e2, ei, ENTRY_BLOCK_PTR->succs) |
275a4187 SB |
1164 | { |
1165 | /* Clear EDGE_EXECUTABLE. This flag is never used in the backend. | |
242229bb | 1166 | |
275a4187 SB |
1167 | For all other blocks this edge flag is cleared while expanding |
1168 | a basic block in expand_gimple_basic_block, but there we never | |
1169 | looked at the successors of the entry block. | |
1170 | This caused PR17513. */ | |
1171 | e2->flags &= ~EDGE_EXECUTABLE; | |
1172 | ||
1173 | if (e2->dest == ENTRY_BLOCK_PTR->next_bb) | |
1174 | e = e2; | |
1175 | } | |
242229bb JH |
1176 | |
1177 | init_block = create_basic_block (NEXT_INSN (get_insns ()), | |
1178 | get_last_insn (), | |
1179 | ENTRY_BLOCK_PTR); | |
1180 | init_block->frequency = ENTRY_BLOCK_PTR->frequency; | |
1181 | init_block->count = ENTRY_BLOCK_PTR->count; | |
1182 | if (e) | |
1183 | { | |
1184 | first_block = e->dest; | |
1185 | redirect_edge_succ (e, init_block); | |
1186 | e = make_edge (init_block, first_block, EDGE_FALLTHRU); | |
1187 | } | |
1188 | else | |
1189 | e = make_edge (init_block, EXIT_BLOCK_PTR, EDGE_FALLTHRU); | |
1190 | e->probability = REG_BR_PROB_BASE; | |
1191 | e->count = ENTRY_BLOCK_PTR->count; | |
1192 | ||
1193 | update_bb_for_insn (init_block); | |
1194 | return init_block; | |
1195 | } | |
1196 | ||
1197 | ||
1198 | /* Create a block containing landing pads and similar stuff. */ | |
1199 | ||
1200 | static void | |
1201 | construct_exit_block (void) | |
1202 | { | |
1203 | rtx head = get_last_insn (); | |
1204 | rtx end; | |
1205 | basic_block exit_block; | |
628f6a4e BE |
1206 | edge e, e2; |
1207 | unsigned ix; | |
1208 | edge_iterator ei; | |
242229bb | 1209 | |
caf93cb0 | 1210 | /* Make sure the locus is set to the end of the function, so that |
242229bb | 1211 | epilogue line numbers and warnings are set properly. */ |
6773e15f PB |
1212 | #ifdef USE_MAPPED_LOCATION |
1213 | if (cfun->function_end_locus != UNKNOWN_LOCATION) | |
1214 | #else | |
242229bb | 1215 | if (cfun->function_end_locus.file) |
6773e15f | 1216 | #endif |
242229bb JH |
1217 | input_location = cfun->function_end_locus; |
1218 | ||
1219 | /* The following insns belong to the top scope. */ | |
1220 | record_block_change (DECL_INITIAL (current_function_decl)); | |
1221 | ||
242229bb JH |
1222 | /* Generate rtl for function exit. */ |
1223 | expand_function_end (); | |
1224 | ||
1225 | end = get_last_insn (); | |
1226 | if (head == end) | |
1227 | return; | |
4b4bf941 | 1228 | while (NEXT_INSN (head) && NOTE_P (NEXT_INSN (head))) |
242229bb | 1229 | head = NEXT_INSN (head); |
80c7a9eb RH |
1230 | exit_block = create_basic_block (NEXT_INSN (head), end, |
1231 | EXIT_BLOCK_PTR->prev_bb); | |
242229bb JH |
1232 | exit_block->frequency = EXIT_BLOCK_PTR->frequency; |
1233 | exit_block->count = EXIT_BLOCK_PTR->count; | |
628f6a4e BE |
1234 | |
1235 | ix = 0; | |
1236 | while (ix < EDGE_COUNT (EXIT_BLOCK_PTR->preds)) | |
242229bb | 1237 | { |
8fb790fd | 1238 | e = EDGE_PRED (EXIT_BLOCK_PTR, ix); |
242229bb | 1239 | if (!(e->flags & EDGE_ABNORMAL)) |
628f6a4e BE |
1240 | redirect_edge_succ (e, exit_block); |
1241 | else | |
1242 | ix++; | |
242229bb | 1243 | } |
628f6a4e | 1244 | |
242229bb JH |
1245 | e = make_edge (exit_block, EXIT_BLOCK_PTR, EDGE_FALLTHRU); |
1246 | e->probability = REG_BR_PROB_BASE; | |
1247 | e->count = EXIT_BLOCK_PTR->count; | |
628f6a4e | 1248 | FOR_EACH_EDGE (e2, ei, EXIT_BLOCK_PTR->preds) |
242229bb JH |
1249 | if (e2 != e) |
1250 | { | |
1251 | e->count -= e2->count; | |
1252 | exit_block->count -= e2->count; | |
1253 | exit_block->frequency -= EDGE_FREQUENCY (e2); | |
1254 | } | |
1255 | if (e->count < 0) | |
1256 | e->count = 0; | |
1257 | if (exit_block->count < 0) | |
1258 | exit_block->count = 0; | |
1259 | if (exit_block->frequency < 0) | |
1260 | exit_block->frequency = 0; | |
1261 | update_bb_for_insn (exit_block); | |
1262 | } | |
1263 | ||
242229bb JH |
1264 | /* Translate the intermediate representation contained in the CFG |
1265 | from GIMPLE trees to RTL. | |
1266 | ||
1267 | We do conversion per basic block and preserve/update the tree CFG. | |
1268 | This implies we have to do some magic as the CFG can simultaneously | |
1269 | consist of basic blocks containing RTL and GIMPLE trees. This can | |
61ada8ae | 1270 | confuse the CFG hooks, so be careful to not manipulate CFG during |
242229bb JH |
1271 | the expansion. */ |
1272 | ||
1273 | static void | |
1274 | tree_expand_cfg (void) | |
1275 | { | |
1276 | basic_block bb, init_block; | |
1277 | sbitmap blocks; | |
1278 | ||
4586b4ca SB |
1279 | /* Some backends want to know that we are expanding to RTL. */ |
1280 | currently_expanding_to_rtl = 1; | |
1281 | ||
6429e3be RH |
1282 | /* Prepare the rtl middle end to start recording block changes. */ |
1283 | reset_block_changes (); | |
1284 | ||
727a31fa | 1285 | /* Expand the variables recorded during gimple lowering. */ |
242229bb JH |
1286 | expand_used_vars (); |
1287 | ||
1288 | /* Set up parameters and prepare for return, for the function. */ | |
b79c5284 | 1289 | expand_function_start (current_function_decl); |
242229bb JH |
1290 | |
1291 | /* If this function is `main', emit a call to `__main' | |
1292 | to run global initializers, etc. */ | |
1293 | if (DECL_NAME (current_function_decl) | |
1294 | && MAIN_NAME_P (DECL_NAME (current_function_decl)) | |
1295 | && DECL_FILE_SCOPE_P (current_function_decl)) | |
1296 | expand_main_function (); | |
1297 | ||
3fbd86b1 | 1298 | /* Register rtl specific functions for cfg. */ |
242229bb JH |
1299 | rtl_register_cfg_hooks (); |
1300 | ||
1301 | init_block = construct_init_block (); | |
1302 | ||
1303 | FOR_BB_BETWEEN (bb, init_block->next_bb, EXIT_BLOCK_PTR, next_bb) | |
80c7a9eb | 1304 | bb = expand_gimple_basic_block (bb, dump_file); |
242229bb JH |
1305 | |
1306 | construct_exit_block (); | |
1307 | ||
4586b4ca SB |
1308 | /* We're done expanding trees to RTL. */ |
1309 | currently_expanding_to_rtl = 0; | |
1310 | ||
f39e46ba SB |
1311 | /* Convert tree EH labels to RTL EH labels, and clean out any unreachable |
1312 | EH regions. */ | |
242229bb JH |
1313 | convert_from_eh_region_ranges (); |
1314 | ||
1315 | rebuild_jump_labels (get_insns ()); | |
1316 | find_exception_handler_labels (); | |
1317 | ||
1318 | blocks = sbitmap_alloc (last_basic_block); | |
1319 | sbitmap_ones (blocks); | |
1320 | find_many_sub_basic_blocks (blocks); | |
25cd19de | 1321 | purge_all_dead_edges (); |
242229bb JH |
1322 | sbitmap_free (blocks); |
1323 | ||
1324 | compact_blocks (); | |
1325 | #ifdef ENABLE_CHECKING | |
1326 | verify_flow_info(); | |
1327 | #endif | |
9f8628ba PB |
1328 | |
1329 | /* There's no need to defer outputting this function any more; we | |
1330 | know we want to output it. */ | |
1331 | DECL_DEFER_OUTPUT (current_function_decl) = 0; | |
1332 | ||
1333 | /* Now that we're done expanding trees to RTL, we shouldn't have any | |
1334 | more CONCATs anywhere. */ | |
1335 | generating_concat_p = 0; | |
1336 | ||
1337 | finalize_block_changes (); | |
b7211528 SB |
1338 | |
1339 | if (dump_file) | |
1340 | { | |
1341 | fprintf (dump_file, | |
1342 | "\n\n;;\n;; Full RTL generated for this function:\n;;\n"); | |
1343 | /* And the pass manager will dump RTL for us. */ | |
1344 | } | |
242229bb JH |
1345 | } |
1346 | ||
1347 | struct tree_opt_pass pass_expand = | |
1348 | { | |
1349 | "expand", /* name */ | |
1350 | NULL, /* gate */ | |
1351 | tree_expand_cfg, /* execute */ | |
1352 | NULL, /* sub */ | |
1353 | NULL, /* next */ | |
1354 | 0, /* static_pass_number */ | |
1355 | TV_EXPAND, /* tv_id */ | |
1356 | /* ??? If TER is enabled, we actually receive GENERIC. */ | |
1357 | PROP_gimple_leh | PROP_cfg, /* properties_required */ | |
1358 | PROP_rtl, /* properties_provided */ | |
1359 | PROP_gimple_leh, /* properties_destroyed */ | |
1360 | 0, /* todo_flags_start */ | |
9f8628ba PB |
1361 | 0, /* todo_flags_finish */ |
1362 | 'r' /* letter */ | |
242229bb | 1363 | }; |