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Commit | Line | Data |
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242229bb | 1 | /* A pass for lowering trees to RTL. |
66647d44 JJ |
2 | Copyright (C) 2004, 2005, 2006, 2007, 2008, 2009 |
3 | Free Software Foundation, Inc. | |
242229bb JH |
4 | |
5 | This file is part of GCC. | |
6 | ||
7 | GCC is free software; you can redistribute it and/or modify | |
8 | it under the terms of the GNU General Public License as published by | |
9dcd6f09 | 9 | the Free Software Foundation; either version 3, or (at your option) |
242229bb JH |
10 | any later version. |
11 | ||
12 | GCC is distributed in the hope that it will be useful, | |
13 | but WITHOUT ANY WARRANTY; without even the implied warranty of | |
14 | MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
15 | GNU General Public License for more details. | |
16 | ||
17 | You should have received a copy of the GNU General Public License | |
9dcd6f09 NC |
18 | along with GCC; see the file COPYING3. If not see |
19 | <http://www.gnu.org/licenses/>. */ | |
242229bb JH |
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" | |
ef330312 | 40 | #include "debug.h" |
7d69de61 | 41 | #include "params.h" |
ff28a94d | 42 | #include "tree-inline.h" |
6946b3f7 | 43 | #include "value-prof.h" |
e41b2a33 | 44 | #include "target.h" |
4e3825db | 45 | #include "ssaexpand.h" |
7d69de61 | 46 | |
726a989a | 47 | |
4e3825db MM |
48 | /* This variable holds information helping the rewriting of SSA trees |
49 | into RTL. */ | |
50 | struct ssaexpand SA; | |
51 | ||
726a989a RB |
52 | /* Return an expression tree corresponding to the RHS of GIMPLE |
53 | statement STMT. */ | |
54 | ||
55 | tree | |
56 | gimple_assign_rhs_to_tree (gimple stmt) | |
57 | { | |
58 | tree t; | |
82d6e6fc | 59 | enum gimple_rhs_class grhs_class; |
726a989a | 60 | |
82d6e6fc | 61 | grhs_class = get_gimple_rhs_class (gimple_expr_code (stmt)); |
726a989a | 62 | |
82d6e6fc | 63 | if (grhs_class == GIMPLE_BINARY_RHS) |
726a989a RB |
64 | t = build2 (gimple_assign_rhs_code (stmt), |
65 | TREE_TYPE (gimple_assign_lhs (stmt)), | |
66 | gimple_assign_rhs1 (stmt), | |
67 | gimple_assign_rhs2 (stmt)); | |
82d6e6fc | 68 | else if (grhs_class == GIMPLE_UNARY_RHS) |
726a989a RB |
69 | t = build1 (gimple_assign_rhs_code (stmt), |
70 | TREE_TYPE (gimple_assign_lhs (stmt)), | |
71 | gimple_assign_rhs1 (stmt)); | |
82d6e6fc | 72 | else if (grhs_class == GIMPLE_SINGLE_RHS) |
726a989a RB |
73 | t = gimple_assign_rhs1 (stmt); |
74 | else | |
75 | gcc_unreachable (); | |
76 | ||
f5045c96 AM |
77 | if (gimple_has_location (stmt) && CAN_HAVE_LOCATION_P (t)) |
78 | SET_EXPR_LOCATION (t, gimple_location (stmt)); | |
79 | ||
726a989a RB |
80 | return t; |
81 | } | |
82 | ||
83 | /* Return an expression tree corresponding to the PREDICATE of GIMPLE_COND | |
84 | statement STMT. */ | |
85 | ||
86 | static tree | |
87 | gimple_cond_pred_to_tree (gimple stmt) | |
88 | { | |
4e3825db MM |
89 | /* We're sometimes presented with such code: |
90 | D.123_1 = x < y; | |
91 | if (D.123_1 != 0) | |
92 | ... | |
93 | This would expand to two comparisons which then later might | |
94 | be cleaned up by combine. But some pattern matchers like if-conversion | |
95 | work better when there's only one compare, so make up for this | |
96 | here as special exception if TER would have made the same change. */ | |
97 | tree lhs = gimple_cond_lhs (stmt); | |
98 | if (SA.values | |
99 | && TREE_CODE (lhs) == SSA_NAME | |
e97809c6 MM |
100 | && bitmap_bit_p (SA.values, SSA_NAME_VERSION (lhs))) |
101 | lhs = gimple_assign_rhs_to_tree (SSA_NAME_DEF_STMT (lhs)); | |
4e3825db | 102 | |
726a989a | 103 | return build2 (gimple_cond_code (stmt), boolean_type_node, |
4e3825db | 104 | lhs, gimple_cond_rhs (stmt)); |
726a989a RB |
105 | } |
106 | ||
107 | /* Helper for gimple_to_tree. Set EXPR_LOCATION for every expression | |
108 | inside *TP. DATA is the location to set. */ | |
109 | ||
110 | static tree | |
111 | set_expr_location_r (tree *tp, int *ws ATTRIBUTE_UNUSED, void *data) | |
112 | { | |
113 | location_t *loc = (location_t *) data; | |
114 | if (EXPR_P (*tp)) | |
115 | SET_EXPR_LOCATION (*tp, *loc); | |
116 | ||
117 | return NULL_TREE; | |
118 | } | |
119 | ||
120 | ||
121 | /* RTL expansion has traditionally been done on trees, so the | |
122 | transition to doing it on GIMPLE tuples is very invasive to the RTL | |
123 | expander. To facilitate the transition, this function takes a | |
124 | GIMPLE tuple STMT and returns the same statement in the form of a | |
125 | tree. */ | |
126 | ||
127 | static tree | |
128 | gimple_to_tree (gimple stmt) | |
129 | { | |
130 | tree t; | |
131 | int rn; | |
132 | tree_ann_common_t ann; | |
133 | location_t loc; | |
134 | ||
135 | switch (gimple_code (stmt)) | |
136 | { | |
137 | case GIMPLE_ASSIGN: | |
138 | { | |
139 | tree lhs = gimple_assign_lhs (stmt); | |
140 | ||
141 | t = gimple_assign_rhs_to_tree (stmt); | |
142 | t = build2 (MODIFY_EXPR, TREE_TYPE (lhs), lhs, t); | |
143 | if (gimple_assign_nontemporal_move_p (stmt)) | |
144 | MOVE_NONTEMPORAL (t) = true; | |
145 | } | |
146 | break; | |
147 | ||
148 | case GIMPLE_COND: | |
149 | t = gimple_cond_pred_to_tree (stmt); | |
150 | t = build3 (COND_EXPR, void_type_node, t, NULL_TREE, NULL_TREE); | |
151 | break; | |
152 | ||
153 | case GIMPLE_GOTO: | |
154 | t = build1 (GOTO_EXPR, void_type_node, gimple_goto_dest (stmt)); | |
155 | break; | |
156 | ||
157 | case GIMPLE_LABEL: | |
158 | t = build1 (LABEL_EXPR, void_type_node, gimple_label_label (stmt)); | |
159 | break; | |
160 | ||
161 | case GIMPLE_RETURN: | |
162 | { | |
163 | tree retval = gimple_return_retval (stmt); | |
164 | ||
165 | if (retval && retval != error_mark_node) | |
166 | { | |
167 | tree result = DECL_RESULT (current_function_decl); | |
168 | ||
169 | /* If we are not returning the current function's RESULT_DECL, | |
170 | build an assignment to it. */ | |
171 | if (retval != result) | |
172 | { | |
173 | /* I believe that a function's RESULT_DECL is unique. */ | |
174 | gcc_assert (TREE_CODE (retval) != RESULT_DECL); | |
175 | ||
176 | retval = build2 (MODIFY_EXPR, TREE_TYPE (result), | |
177 | result, retval); | |
178 | } | |
179 | } | |
180 | t = build1 (RETURN_EXPR, void_type_node, retval); | |
181 | } | |
182 | break; | |
183 | ||
184 | case GIMPLE_ASM: | |
185 | { | |
186 | size_t i, n; | |
187 | tree out, in, cl; | |
188 | const char *s; | |
189 | ||
190 | out = NULL_TREE; | |
191 | n = gimple_asm_noutputs (stmt); | |
192 | if (n > 0) | |
193 | { | |
194 | t = out = gimple_asm_output_op (stmt, 0); | |
195 | for (i = 1; i < n; i++) | |
196 | { | |
197 | TREE_CHAIN (t) = gimple_asm_output_op (stmt, i); | |
198 | t = gimple_asm_output_op (stmt, i); | |
199 | } | |
200 | } | |
201 | ||
202 | in = NULL_TREE; | |
203 | n = gimple_asm_ninputs (stmt); | |
204 | if (n > 0) | |
205 | { | |
206 | t = in = gimple_asm_input_op (stmt, 0); | |
207 | for (i = 1; i < n; i++) | |
208 | { | |
209 | TREE_CHAIN (t) = gimple_asm_input_op (stmt, i); | |
210 | t = gimple_asm_input_op (stmt, i); | |
211 | } | |
212 | } | |
213 | ||
214 | cl = NULL_TREE; | |
215 | n = gimple_asm_nclobbers (stmt); | |
216 | if (n > 0) | |
217 | { | |
218 | t = cl = gimple_asm_clobber_op (stmt, 0); | |
219 | for (i = 1; i < n; i++) | |
220 | { | |
221 | TREE_CHAIN (t) = gimple_asm_clobber_op (stmt, i); | |
222 | t = gimple_asm_clobber_op (stmt, i); | |
223 | } | |
224 | } | |
225 | ||
226 | s = gimple_asm_string (stmt); | |
227 | t = build4 (ASM_EXPR, void_type_node, build_string (strlen (s), s), | |
228 | out, in, cl); | |
229 | ASM_VOLATILE_P (t) = gimple_asm_volatile_p (stmt); | |
230 | ASM_INPUT_P (t) = gimple_asm_input_p (stmt); | |
231 | } | |
232 | break; | |
233 | ||
234 | case GIMPLE_CALL: | |
235 | { | |
236 | size_t i; | |
237 | tree fn; | |
238 | tree_ann_common_t ann; | |
239 | ||
240 | t = build_vl_exp (CALL_EXPR, gimple_call_num_args (stmt) + 3); | |
241 | ||
7c9577be | 242 | CALL_EXPR_FN (t) = gimple_call_fn (stmt); |
726a989a | 243 | TREE_TYPE (t) = gimple_call_return_type (stmt); |
726a989a RB |
244 | CALL_EXPR_STATIC_CHAIN (t) = gimple_call_chain (stmt); |
245 | ||
246 | for (i = 0; i < gimple_call_num_args (stmt); i++) | |
247 | CALL_EXPR_ARG (t, i) = gimple_call_arg (stmt, i); | |
248 | ||
249 | if (!(gimple_call_flags (stmt) & (ECF_CONST | ECF_PURE))) | |
250 | TREE_SIDE_EFFECTS (t) = 1; | |
251 | ||
252 | if (gimple_call_flags (stmt) & ECF_NOTHROW) | |
253 | TREE_NOTHROW (t) = 1; | |
254 | ||
255 | CALL_EXPR_TAILCALL (t) = gimple_call_tail_p (stmt); | |
256 | CALL_EXPR_RETURN_SLOT_OPT (t) = gimple_call_return_slot_opt_p (stmt); | |
257 | CALL_FROM_THUNK_P (t) = gimple_call_from_thunk_p (stmt); | |
258 | CALL_CANNOT_INLINE_P (t) = gimple_call_cannot_inline_p (stmt); | |
259 | CALL_EXPR_VA_ARG_PACK (t) = gimple_call_va_arg_pack_p (stmt); | |
260 | ||
261 | /* If the call has a LHS then create a MODIFY_EXPR to hold it. */ | |
262 | { | |
263 | tree lhs = gimple_call_lhs (stmt); | |
264 | ||
265 | if (lhs) | |
266 | t = build2 (MODIFY_EXPR, TREE_TYPE (lhs), lhs, t); | |
267 | } | |
268 | ||
269 | /* Record the original call statement, as it may be used | |
270 | to retrieve profile information during expansion. */ | |
7c9577be RG |
271 | |
272 | if ((fn = gimple_call_fndecl (stmt)) != NULL_TREE | |
273 | && DECL_BUILT_IN (fn)) | |
726a989a RB |
274 | { |
275 | ann = get_tree_common_ann (t); | |
276 | ann->stmt = stmt; | |
277 | } | |
278 | } | |
279 | break; | |
280 | ||
281 | case GIMPLE_SWITCH: | |
282 | { | |
283 | tree label_vec; | |
284 | size_t i; | |
285 | tree elt = gimple_switch_label (stmt, 0); | |
286 | ||
287 | label_vec = make_tree_vec (gimple_switch_num_labels (stmt)); | |
288 | ||
289 | if (!CASE_LOW (elt) && !CASE_HIGH (elt)) | |
290 | { | |
291 | for (i = 1; i < gimple_switch_num_labels (stmt); i++) | |
292 | TREE_VEC_ELT (label_vec, i - 1) = gimple_switch_label (stmt, i); | |
293 | ||
294 | /* The default case in a SWITCH_EXPR must be at the end of | |
295 | the label vector. */ | |
296 | TREE_VEC_ELT (label_vec, i - 1) = gimple_switch_label (stmt, 0); | |
297 | } | |
298 | else | |
299 | { | |
300 | for (i = 0; i < gimple_switch_num_labels (stmt); i++) | |
301 | TREE_VEC_ELT (label_vec, i) = gimple_switch_label (stmt, i); | |
302 | } | |
303 | ||
304 | t = build3 (SWITCH_EXPR, void_type_node, gimple_switch_index (stmt), | |
305 | NULL, label_vec); | |
306 | } | |
307 | break; | |
308 | ||
309 | case GIMPLE_NOP: | |
310 | case GIMPLE_PREDICT: | |
311 | t = build1 (NOP_EXPR, void_type_node, size_zero_node); | |
312 | break; | |
313 | ||
314 | case GIMPLE_RESX: | |
315 | t = build_resx (gimple_resx_region (stmt)); | |
316 | break; | |
317 | ||
318 | default: | |
319 | if (errorcount == 0) | |
320 | { | |
321 | error ("Unrecognized GIMPLE statement during RTL expansion"); | |
322 | print_gimple_stmt (stderr, stmt, 4, 0); | |
323 | gcc_unreachable (); | |
324 | } | |
325 | else | |
326 | { | |
327 | /* Ignore any bad gimple codes if we're going to die anyhow, | |
328 | so we can at least set TREE_ASM_WRITTEN and have the rest | |
329 | of compilation advance without sudden ICE death. */ | |
330 | t = build1 (NOP_EXPR, void_type_node, size_zero_node); | |
331 | break; | |
332 | } | |
333 | } | |
334 | ||
335 | /* If STMT is inside an exception region, record it in the generated | |
336 | expression. */ | |
337 | rn = lookup_stmt_eh_region (stmt); | |
338 | if (rn >= 0) | |
339 | { | |
340 | tree call = get_call_expr_in (t); | |
341 | ||
342 | ann = get_tree_common_ann (t); | |
343 | ann->rn = rn; | |
344 | ||
345 | /* For a CALL_EXPR on the RHS of an assignment, calls.c looks up | |
346 | the CALL_EXPR not the assignment statment for EH region number. */ | |
347 | if (call && call != t) | |
348 | { | |
349 | ann = get_tree_common_ann (call); | |
350 | ann->rn = rn; | |
351 | } | |
352 | } | |
353 | ||
354 | /* Set EXPR_LOCATION in all the embedded expressions. */ | |
355 | loc = gimple_location (stmt); | |
356 | walk_tree (&t, set_expr_location_r, (void *) &loc, NULL); | |
357 | ||
358 | TREE_BLOCK (t) = gimple_block (stmt); | |
359 | ||
360 | return t; | |
361 | } | |
362 | ||
363 | ||
364 | /* Release back to GC memory allocated by gimple_to_tree. */ | |
365 | ||
366 | static void | |
367 | release_stmt_tree (gimple stmt, tree stmt_tree) | |
368 | { | |
369 | tree_ann_common_t ann; | |
370 | ||
371 | switch (gimple_code (stmt)) | |
372 | { | |
373 | case GIMPLE_ASSIGN: | |
374 | if (get_gimple_rhs_class (gimple_expr_code (stmt)) != GIMPLE_SINGLE_RHS) | |
375 | ggc_free (TREE_OPERAND (stmt_tree, 1)); | |
376 | break; | |
377 | case GIMPLE_COND: | |
378 | ggc_free (COND_EXPR_COND (stmt_tree)); | |
379 | break; | |
380 | case GIMPLE_RETURN: | |
381 | if (TREE_OPERAND (stmt_tree, 0) | |
382 | && TREE_CODE (TREE_OPERAND (stmt_tree, 0)) == MODIFY_EXPR) | |
383 | ggc_free (TREE_OPERAND (stmt_tree, 0)); | |
384 | break; | |
385 | case GIMPLE_CALL: | |
386 | if (gimple_call_lhs (stmt)) | |
387 | { | |
726a989a RB |
388 | ann = tree_common_ann (TREE_OPERAND (stmt_tree, 1)); |
389 | if (ann) | |
390 | ggc_free (ann); | |
391 | ggc_free (TREE_OPERAND (stmt_tree, 1)); | |
392 | } | |
726a989a RB |
393 | break; |
394 | default: | |
395 | break; | |
396 | } | |
397 | ann = tree_common_ann (stmt_tree); | |
398 | if (ann) | |
399 | ggc_free (ann); | |
400 | ggc_free (stmt_tree); | |
401 | } | |
402 | ||
403 | ||
e53de54d JH |
404 | /* Verify that there is exactly single jump instruction since last and attach |
405 | REG_BR_PROB note specifying probability. | |
406 | ??? We really ought to pass the probability down to RTL expanders and let it | |
d7e9e62a KH |
407 | re-distribute it when the conditional expands into multiple conditionals. |
408 | This is however difficult to do. */ | |
ef950eba | 409 | void |
10d22567 | 410 | add_reg_br_prob_note (rtx last, int probability) |
e53de54d JH |
411 | { |
412 | if (profile_status == PROFILE_ABSENT) | |
413 | return; | |
414 | for (last = NEXT_INSN (last); last && NEXT_INSN (last); last = NEXT_INSN (last)) | |
2ca202e7 | 415 | if (JUMP_P (last)) |
e53de54d JH |
416 | { |
417 | /* It is common to emit condjump-around-jump sequence when we don't know | |
418 | how to reverse the conditional. Special case this. */ | |
419 | if (!any_condjump_p (last) | |
2ca202e7 | 420 | || !JUMP_P (NEXT_INSN (last)) |
e53de54d | 421 | || !simplejump_p (NEXT_INSN (last)) |
fa1ff4eb | 422 | || !NEXT_INSN (NEXT_INSN (last)) |
2ca202e7 | 423 | || !BARRIER_P (NEXT_INSN (NEXT_INSN (last))) |
fa1ff4eb | 424 | || !NEXT_INSN (NEXT_INSN (NEXT_INSN (last))) |
2ca202e7 | 425 | || !LABEL_P (NEXT_INSN (NEXT_INSN (NEXT_INSN (last)))) |
e53de54d JH |
426 | || NEXT_INSN (NEXT_INSN (NEXT_INSN (NEXT_INSN (last))))) |
427 | goto failed; | |
41806d92 | 428 | gcc_assert (!find_reg_note (last, REG_BR_PROB, 0)); |
65c5f2a6 ILT |
429 | add_reg_note (last, REG_BR_PROB, |
430 | GEN_INT (REG_BR_PROB_BASE - probability)); | |
e53de54d JH |
431 | return; |
432 | } | |
2ca202e7 | 433 | if (!last || !JUMP_P (last) || !any_condjump_p (last)) |
41806d92 NS |
434 | goto failed; |
435 | gcc_assert (!find_reg_note (last, REG_BR_PROB, 0)); | |
65c5f2a6 | 436 | add_reg_note (last, REG_BR_PROB, GEN_INT (probability)); |
e53de54d JH |
437 | return; |
438 | failed: | |
439 | if (dump_file) | |
440 | fprintf (dump_file, "Failed to add probability note\n"); | |
441 | } | |
442 | ||
80c7a9eb | 443 | |
1f6d3a08 RH |
444 | #ifndef STACK_ALIGNMENT_NEEDED |
445 | #define STACK_ALIGNMENT_NEEDED 1 | |
446 | #endif | |
447 | ||
4e3825db MM |
448 | #define SSAVAR(x) (TREE_CODE (x) == SSA_NAME ? SSA_NAME_VAR (x) : x) |
449 | ||
450 | /* Associate declaration T with storage space X. If T is no | |
451 | SSA name this is exactly SET_DECL_RTL, otherwise make the | |
452 | partition of T associated with X. */ | |
453 | static inline void | |
454 | set_rtl (tree t, rtx x) | |
455 | { | |
456 | if (TREE_CODE (t) == SSA_NAME) | |
457 | { | |
458 | SA.partition_to_pseudo[var_to_partition (SA.map, t)] = x; | |
459 | if (x && !MEM_P (x)) | |
460 | set_reg_attrs_for_decl_rtl (SSA_NAME_VAR (t), x); | |
eb7adebc MM |
461 | /* For the benefit of debug information at -O0 (where vartracking |
462 | doesn't run) record the place also in the base DECL if it's | |
463 | a normal variable (not a parameter). */ | |
464 | if (x && x != pc_rtx && TREE_CODE (SSA_NAME_VAR (t)) == VAR_DECL) | |
465 | { | |
466 | tree var = SSA_NAME_VAR (t); | |
467 | /* If we don't yet have something recorded, just record it now. */ | |
468 | if (!DECL_RTL_SET_P (var)) | |
469 | SET_DECL_RTL (var, x); | |
470 | /* If we have it set alrady to "multiple places" don't | |
471 | change this. */ | |
472 | else if (DECL_RTL (var) == pc_rtx) | |
473 | ; | |
474 | /* If we have something recorded and it's not the same place | |
475 | as we want to record now, we have multiple partitions for the | |
476 | same base variable, with different places. We can't just | |
477 | randomly chose one, hence we have to say that we don't know. | |
478 | This only happens with optimization, and there var-tracking | |
479 | will figure out the right thing. */ | |
480 | else if (DECL_RTL (var) != x) | |
481 | SET_DECL_RTL (var, pc_rtx); | |
482 | } | |
4e3825db MM |
483 | } |
484 | else | |
485 | SET_DECL_RTL (t, x); | |
486 | } | |
1f6d3a08 RH |
487 | |
488 | /* This structure holds data relevant to one variable that will be | |
489 | placed in a stack slot. */ | |
490 | struct stack_var | |
491 | { | |
492 | /* The Variable. */ | |
493 | tree decl; | |
494 | ||
495 | /* The offset of the variable. During partitioning, this is the | |
496 | offset relative to the partition. After partitioning, this | |
497 | is relative to the stack frame. */ | |
498 | HOST_WIDE_INT offset; | |
499 | ||
500 | /* Initially, the size of the variable. Later, the size of the partition, | |
501 | if this variable becomes it's partition's representative. */ | |
502 | HOST_WIDE_INT size; | |
503 | ||
504 | /* The *byte* alignment required for this variable. Or as, with the | |
505 | size, the alignment for this partition. */ | |
506 | unsigned int alignb; | |
507 | ||
508 | /* The partition representative. */ | |
509 | size_t representative; | |
510 | ||
511 | /* The next stack variable in the partition, or EOC. */ | |
512 | size_t next; | |
513 | }; | |
514 | ||
515 | #define EOC ((size_t)-1) | |
516 | ||
517 | /* We have an array of such objects while deciding allocation. */ | |
518 | static struct stack_var *stack_vars; | |
519 | static size_t stack_vars_alloc; | |
520 | static size_t stack_vars_num; | |
521 | ||
fa10beec | 522 | /* An array of indices such that stack_vars[stack_vars_sorted[i]].size |
1f6d3a08 RH |
523 | is non-decreasing. */ |
524 | static size_t *stack_vars_sorted; | |
525 | ||
526 | /* We have an interference graph between such objects. This graph | |
527 | is lower triangular. */ | |
528 | static bool *stack_vars_conflict; | |
529 | static size_t stack_vars_conflict_alloc; | |
530 | ||
531 | /* The phase of the stack frame. This is the known misalignment of | |
532 | virtual_stack_vars_rtx from PREFERRED_STACK_BOUNDARY. That is, | |
533 | (frame_offset+frame_phase) % PREFERRED_STACK_BOUNDARY == 0. */ | |
534 | static int frame_phase; | |
535 | ||
7d69de61 RH |
536 | /* Used during expand_used_vars to remember if we saw any decls for |
537 | which we'd like to enable stack smashing protection. */ | |
538 | static bool has_protected_decls; | |
539 | ||
540 | /* Used during expand_used_vars. Remember if we say a character buffer | |
541 | smaller than our cutoff threshold. Used for -Wstack-protector. */ | |
542 | static bool has_short_buffer; | |
1f6d3a08 RH |
543 | |
544 | /* Discover the byte alignment to use for DECL. Ignore alignment | |
545 | we can't do with expected alignment of the stack boundary. */ | |
546 | ||
547 | static unsigned int | |
548 | get_decl_align_unit (tree decl) | |
549 | { | |
550 | unsigned int align; | |
551 | ||
9bfaf89d | 552 | align = LOCAL_DECL_ALIGNMENT (decl); |
2e3f842f L |
553 | |
554 | if (align > MAX_SUPPORTED_STACK_ALIGNMENT) | |
555 | align = MAX_SUPPORTED_STACK_ALIGNMENT; | |
556 | ||
557 | if (SUPPORTS_STACK_ALIGNMENT) | |
558 | { | |
559 | if (crtl->stack_alignment_estimated < align) | |
560 | { | |
561 | gcc_assert(!crtl->stack_realign_processed); | |
562 | crtl->stack_alignment_estimated = align; | |
563 | } | |
564 | } | |
565 | ||
566 | /* stack_alignment_needed > PREFERRED_STACK_BOUNDARY is permitted. | |
567 | So here we only make sure stack_alignment_needed >= align. */ | |
cb91fab0 JH |
568 | if (crtl->stack_alignment_needed < align) |
569 | crtl->stack_alignment_needed = align; | |
f85882d8 JY |
570 | if (crtl->max_used_stack_slot_alignment < align) |
571 | crtl->max_used_stack_slot_alignment = align; | |
1f6d3a08 RH |
572 | |
573 | return align / BITS_PER_UNIT; | |
574 | } | |
575 | ||
576 | /* Allocate SIZE bytes at byte alignment ALIGN from the stack frame. | |
577 | Return the frame offset. */ | |
578 | ||
579 | static HOST_WIDE_INT | |
580 | alloc_stack_frame_space (HOST_WIDE_INT size, HOST_WIDE_INT align) | |
581 | { | |
582 | HOST_WIDE_INT offset, new_frame_offset; | |
583 | ||
584 | new_frame_offset = frame_offset; | |
585 | if (FRAME_GROWS_DOWNWARD) | |
586 | { | |
587 | new_frame_offset -= size + frame_phase; | |
588 | new_frame_offset &= -align; | |
589 | new_frame_offset += frame_phase; | |
590 | offset = new_frame_offset; | |
591 | } | |
592 | else | |
593 | { | |
594 | new_frame_offset -= frame_phase; | |
595 | new_frame_offset += align - 1; | |
596 | new_frame_offset &= -align; | |
597 | new_frame_offset += frame_phase; | |
598 | offset = new_frame_offset; | |
599 | new_frame_offset += size; | |
600 | } | |
601 | frame_offset = new_frame_offset; | |
602 | ||
9fb798d7 EB |
603 | if (frame_offset_overflow (frame_offset, cfun->decl)) |
604 | frame_offset = offset = 0; | |
605 | ||
1f6d3a08 RH |
606 | return offset; |
607 | } | |
608 | ||
609 | /* Accumulate DECL into STACK_VARS. */ | |
610 | ||
611 | static void | |
612 | add_stack_var (tree decl) | |
613 | { | |
614 | if (stack_vars_num >= stack_vars_alloc) | |
615 | { | |
616 | if (stack_vars_alloc) | |
617 | stack_vars_alloc = stack_vars_alloc * 3 / 2; | |
618 | else | |
619 | stack_vars_alloc = 32; | |
620 | stack_vars | |
621 | = XRESIZEVEC (struct stack_var, stack_vars, stack_vars_alloc); | |
622 | } | |
623 | stack_vars[stack_vars_num].decl = decl; | |
624 | stack_vars[stack_vars_num].offset = 0; | |
4e3825db MM |
625 | stack_vars[stack_vars_num].size = tree_low_cst (DECL_SIZE_UNIT (SSAVAR (decl)), 1); |
626 | stack_vars[stack_vars_num].alignb = get_decl_align_unit (SSAVAR (decl)); | |
1f6d3a08 RH |
627 | |
628 | /* All variables are initially in their own partition. */ | |
629 | stack_vars[stack_vars_num].representative = stack_vars_num; | |
630 | stack_vars[stack_vars_num].next = EOC; | |
631 | ||
632 | /* Ensure that this decl doesn't get put onto the list twice. */ | |
4e3825db | 633 | set_rtl (decl, pc_rtx); |
1f6d3a08 RH |
634 | |
635 | stack_vars_num++; | |
636 | } | |
637 | ||
638 | /* Compute the linear index of a lower-triangular coordinate (I, J). */ | |
639 | ||
640 | static size_t | |
641 | triangular_index (size_t i, size_t j) | |
642 | { | |
643 | if (i < j) | |
644 | { | |
645 | size_t t; | |
646 | t = i, i = j, j = t; | |
647 | } | |
648 | return (i * (i + 1)) / 2 + j; | |
649 | } | |
650 | ||
651 | /* Ensure that STACK_VARS_CONFLICT is large enough for N objects. */ | |
652 | ||
653 | static void | |
654 | resize_stack_vars_conflict (size_t n) | |
655 | { | |
656 | size_t size = triangular_index (n-1, n-1) + 1; | |
657 | ||
658 | if (size <= stack_vars_conflict_alloc) | |
659 | return; | |
660 | ||
661 | stack_vars_conflict = XRESIZEVEC (bool, stack_vars_conflict, size); | |
662 | memset (stack_vars_conflict + stack_vars_conflict_alloc, 0, | |
663 | (size - stack_vars_conflict_alloc) * sizeof (bool)); | |
664 | stack_vars_conflict_alloc = size; | |
665 | } | |
666 | ||
667 | /* Make the decls associated with luid's X and Y conflict. */ | |
668 | ||
669 | static void | |
670 | add_stack_var_conflict (size_t x, size_t y) | |
671 | { | |
672 | size_t index = triangular_index (x, y); | |
673 | gcc_assert (index < stack_vars_conflict_alloc); | |
674 | stack_vars_conflict[index] = true; | |
675 | } | |
676 | ||
677 | /* Check whether the decls associated with luid's X and Y conflict. */ | |
678 | ||
679 | static bool | |
680 | stack_var_conflict_p (size_t x, size_t y) | |
681 | { | |
682 | size_t index = triangular_index (x, y); | |
683 | gcc_assert (index < stack_vars_conflict_alloc); | |
684 | return stack_vars_conflict[index]; | |
685 | } | |
d239ed56 SB |
686 | |
687 | /* Returns true if TYPE is or contains a union type. */ | |
688 | ||
689 | static bool | |
690 | aggregate_contains_union_type (tree type) | |
691 | { | |
692 | tree field; | |
693 | ||
694 | if (TREE_CODE (type) == UNION_TYPE | |
695 | || TREE_CODE (type) == QUAL_UNION_TYPE) | |
696 | return true; | |
697 | if (TREE_CODE (type) == ARRAY_TYPE) | |
698 | return aggregate_contains_union_type (TREE_TYPE (type)); | |
699 | if (TREE_CODE (type) != RECORD_TYPE) | |
700 | return false; | |
701 | ||
702 | for (field = TYPE_FIELDS (type); field; field = TREE_CHAIN (field)) | |
703 | if (TREE_CODE (field) == FIELD_DECL) | |
704 | if (aggregate_contains_union_type (TREE_TYPE (field))) | |
705 | return true; | |
706 | ||
707 | return false; | |
708 | } | |
709 | ||
1f6d3a08 RH |
710 | /* A subroutine of expand_used_vars. If two variables X and Y have alias |
711 | sets that do not conflict, then do add a conflict for these variables | |
d239ed56 SB |
712 | in the interference graph. We also need to make sure to add conflicts |
713 | for union containing structures. Else RTL alias analysis comes along | |
714 | and due to type based aliasing rules decides that for two overlapping | |
715 | union temporaries { short s; int i; } accesses to the same mem through | |
716 | different types may not alias and happily reorders stores across | |
717 | life-time boundaries of the temporaries (See PR25654). | |
718 | We also have to mind MEM_IN_STRUCT_P and MEM_SCALAR_P. */ | |
1f6d3a08 RH |
719 | |
720 | static void | |
721 | add_alias_set_conflicts (void) | |
722 | { | |
723 | size_t i, j, n = stack_vars_num; | |
724 | ||
725 | for (i = 0; i < n; ++i) | |
726 | { | |
a4d25453 RH |
727 | tree type_i = TREE_TYPE (stack_vars[i].decl); |
728 | bool aggr_i = AGGREGATE_TYPE_P (type_i); | |
d239ed56 | 729 | bool contains_union; |
1f6d3a08 | 730 | |
d239ed56 | 731 | contains_union = aggregate_contains_union_type (type_i); |
1f6d3a08 RH |
732 | for (j = 0; j < i; ++j) |
733 | { | |
a4d25453 RH |
734 | tree type_j = TREE_TYPE (stack_vars[j].decl); |
735 | bool aggr_j = AGGREGATE_TYPE_P (type_j); | |
d239ed56 SB |
736 | if (aggr_i != aggr_j |
737 | /* Either the objects conflict by means of type based | |
738 | aliasing rules, or we need to add a conflict. */ | |
739 | || !objects_must_conflict_p (type_i, type_j) | |
740 | /* In case the types do not conflict ensure that access | |
741 | to elements will conflict. In case of unions we have | |
742 | to be careful as type based aliasing rules may say | |
743 | access to the same memory does not conflict. So play | |
744 | safe and add a conflict in this case. */ | |
745 | || contains_union) | |
1f6d3a08 RH |
746 | add_stack_var_conflict (i, j); |
747 | } | |
748 | } | |
749 | } | |
750 | ||
751 | /* A subroutine of partition_stack_vars. A comparison function for qsort, | |
4e3825db | 752 | sorting an array of indices by the size and type of the object. */ |
1f6d3a08 RH |
753 | |
754 | static int | |
755 | stack_var_size_cmp (const void *a, const void *b) | |
756 | { | |
757 | HOST_WIDE_INT sa = stack_vars[*(const size_t *)a].size; | |
758 | HOST_WIDE_INT sb = stack_vars[*(const size_t *)b].size; | |
4e3825db MM |
759 | tree decla, declb; |
760 | unsigned int uida, uidb; | |
1f6d3a08 RH |
761 | |
762 | if (sa < sb) | |
763 | return -1; | |
764 | if (sa > sb) | |
765 | return 1; | |
4e3825db MM |
766 | decla = stack_vars[*(const size_t *)a].decl; |
767 | declb = stack_vars[*(const size_t *)b].decl; | |
768 | /* For stack variables of the same size use and id of the decls | |
769 | to make the sort stable. Two SSA names are compared by their | |
770 | version, SSA names come before non-SSA names, and two normal | |
771 | decls are compared by their DECL_UID. */ | |
772 | if (TREE_CODE (decla) == SSA_NAME) | |
773 | { | |
774 | if (TREE_CODE (declb) == SSA_NAME) | |
775 | uida = SSA_NAME_VERSION (decla), uidb = SSA_NAME_VERSION (declb); | |
776 | else | |
777 | return -1; | |
778 | } | |
779 | else if (TREE_CODE (declb) == SSA_NAME) | |
780 | return 1; | |
781 | else | |
782 | uida = DECL_UID (decla), uidb = DECL_UID (declb); | |
79f802f5 RG |
783 | if (uida < uidb) |
784 | return -1; | |
785 | if (uida > uidb) | |
786 | return 1; | |
1f6d3a08 RH |
787 | return 0; |
788 | } | |
789 | ||
55b34b5f RG |
790 | |
791 | /* If the points-to solution *PI points to variables that are in a partition | |
792 | together with other variables add all partition members to the pointed-to | |
793 | variables bitmap. */ | |
794 | ||
795 | static void | |
796 | add_partitioned_vars_to_ptset (struct pt_solution *pt, | |
797 | struct pointer_map_t *decls_to_partitions, | |
798 | struct pointer_set_t *visited, bitmap temp) | |
799 | { | |
800 | bitmap_iterator bi; | |
801 | unsigned i; | |
802 | bitmap *part; | |
803 | ||
804 | if (pt->anything | |
805 | || pt->vars == NULL | |
806 | /* The pointed-to vars bitmap is shared, it is enough to | |
807 | visit it once. */ | |
808 | || pointer_set_insert(visited, pt->vars)) | |
809 | return; | |
810 | ||
811 | bitmap_clear (temp); | |
812 | ||
813 | /* By using a temporary bitmap to store all members of the partitions | |
814 | we have to add we make sure to visit each of the partitions only | |
815 | once. */ | |
816 | EXECUTE_IF_SET_IN_BITMAP (pt->vars, 0, i, bi) | |
817 | if ((!temp | |
818 | || !bitmap_bit_p (temp, i)) | |
819 | && (part = (bitmap *) pointer_map_contains (decls_to_partitions, | |
820 | (void *)(size_t) i))) | |
821 | bitmap_ior_into (temp, *part); | |
822 | if (!bitmap_empty_p (temp)) | |
823 | bitmap_ior_into (pt->vars, temp); | |
824 | } | |
825 | ||
826 | /* Update points-to sets based on partition info, so we can use them on RTL. | |
827 | The bitmaps representing stack partitions will be saved until expand, | |
828 | where partitioned decls used as bases in memory expressions will be | |
829 | rewritten. */ | |
830 | ||
831 | static void | |
832 | update_alias_info_with_stack_vars (void) | |
833 | { | |
834 | struct pointer_map_t *decls_to_partitions = NULL; | |
835 | size_t i, j; | |
836 | tree var = NULL_TREE; | |
837 | ||
838 | for (i = 0; i < stack_vars_num; i++) | |
839 | { | |
840 | bitmap part = NULL; | |
841 | tree name; | |
842 | struct ptr_info_def *pi; | |
843 | ||
844 | /* Not interested in partitions with single variable. */ | |
845 | if (stack_vars[i].representative != i | |
846 | || stack_vars[i].next == EOC) | |
847 | continue; | |
848 | ||
849 | if (!decls_to_partitions) | |
850 | { | |
851 | decls_to_partitions = pointer_map_create (); | |
852 | cfun->gimple_df->decls_to_pointers = pointer_map_create (); | |
853 | } | |
854 | ||
855 | /* Create an SSA_NAME that points to the partition for use | |
856 | as base during alias-oracle queries on RTL for bases that | |
857 | have been partitioned. */ | |
858 | if (var == NULL_TREE) | |
859 | var = create_tmp_var (ptr_type_node, NULL); | |
860 | name = make_ssa_name (var, NULL); | |
861 | ||
862 | /* Create bitmaps representing partitions. They will be used for | |
863 | points-to sets later, so use GGC alloc. */ | |
864 | part = BITMAP_GGC_ALLOC (); | |
865 | for (j = i; j != EOC; j = stack_vars[j].next) | |
866 | { | |
867 | tree decl = stack_vars[j].decl; | |
868 | unsigned int uid = DECL_UID (decl); | |
869 | /* We should never end up partitioning SSA names (though they | |
870 | may end up on the stack). Neither should we allocate stack | |
871 | space to something that is unused and thus unreferenced. */ | |
872 | gcc_assert (DECL_P (decl) | |
873 | && referenced_var_lookup (uid)); | |
874 | bitmap_set_bit (part, uid); | |
875 | *((bitmap *) pointer_map_insert (decls_to_partitions, | |
876 | (void *)(size_t) uid)) = part; | |
877 | *((tree *) pointer_map_insert (cfun->gimple_df->decls_to_pointers, | |
878 | decl)) = name; | |
879 | } | |
880 | ||
881 | /* Make the SSA name point to all partition members. */ | |
882 | pi = get_ptr_info (name); | |
883 | pt_solution_set (&pi->pt, part); | |
884 | } | |
885 | ||
886 | /* Make all points-to sets that contain one member of a partition | |
887 | contain all members of the partition. */ | |
888 | if (decls_to_partitions) | |
889 | { | |
890 | unsigned i; | |
891 | struct pointer_set_t *visited = pointer_set_create (); | |
892 | bitmap temp = BITMAP_ALLOC (NULL); | |
893 | ||
894 | for (i = 1; i < num_ssa_names; i++) | |
895 | { | |
896 | tree name = ssa_name (i); | |
897 | struct ptr_info_def *pi; | |
898 | ||
899 | if (name | |
900 | && POINTER_TYPE_P (TREE_TYPE (name)) | |
901 | && ((pi = SSA_NAME_PTR_INFO (name)) != NULL)) | |
902 | add_partitioned_vars_to_ptset (&pi->pt, decls_to_partitions, | |
903 | visited, temp); | |
904 | } | |
905 | ||
906 | add_partitioned_vars_to_ptset (&cfun->gimple_df->escaped, | |
907 | decls_to_partitions, visited, temp); | |
908 | add_partitioned_vars_to_ptset (&cfun->gimple_df->callused, | |
909 | decls_to_partitions, visited, temp); | |
910 | ||
911 | pointer_set_destroy (visited); | |
912 | pointer_map_destroy (decls_to_partitions); | |
913 | BITMAP_FREE (temp); | |
914 | } | |
915 | } | |
916 | ||
1f6d3a08 RH |
917 | /* A subroutine of partition_stack_vars. The UNION portion of a UNION/FIND |
918 | partitioning algorithm. Partitions A and B are known to be non-conflicting. | |
919 | Merge them into a single partition A. | |
920 | ||
921 | At the same time, add OFFSET to all variables in partition B. At the end | |
922 | of the partitioning process we've have a nice block easy to lay out within | |
923 | the stack frame. */ | |
924 | ||
925 | static void | |
926 | union_stack_vars (size_t a, size_t b, HOST_WIDE_INT offset) | |
927 | { | |
928 | size_t i, last; | |
929 | ||
930 | /* Update each element of partition B with the given offset, | |
931 | and merge them into partition A. */ | |
932 | for (last = i = b; i != EOC; last = i, i = stack_vars[i].next) | |
933 | { | |
934 | stack_vars[i].offset += offset; | |
935 | stack_vars[i].representative = a; | |
936 | } | |
937 | stack_vars[last].next = stack_vars[a].next; | |
938 | stack_vars[a].next = b; | |
939 | ||
940 | /* Update the required alignment of partition A to account for B. */ | |
941 | if (stack_vars[a].alignb < stack_vars[b].alignb) | |
942 | stack_vars[a].alignb = stack_vars[b].alignb; | |
943 | ||
944 | /* Update the interference graph and merge the conflicts. */ | |
945 | for (last = stack_vars_num, i = 0; i < last; ++i) | |
946 | if (stack_var_conflict_p (b, i)) | |
947 | add_stack_var_conflict (a, i); | |
948 | } | |
949 | ||
950 | /* A subroutine of expand_used_vars. Binpack the variables into | |
951 | partitions constrained by the interference graph. The overall | |
952 | algorithm used is as follows: | |
953 | ||
954 | Sort the objects by size. | |
955 | For each object A { | |
956 | S = size(A) | |
957 | O = 0 | |
958 | loop { | |
959 | Look for the largest non-conflicting object B with size <= S. | |
960 | UNION (A, B) | |
961 | offset(B) = O | |
962 | O += size(B) | |
963 | S -= size(B) | |
964 | } | |
965 | } | |
966 | */ | |
967 | ||
968 | static void | |
969 | partition_stack_vars (void) | |
970 | { | |
971 | size_t si, sj, n = stack_vars_num; | |
972 | ||
973 | stack_vars_sorted = XNEWVEC (size_t, stack_vars_num); | |
974 | for (si = 0; si < n; ++si) | |
975 | stack_vars_sorted[si] = si; | |
976 | ||
977 | if (n == 1) | |
978 | return; | |
979 | ||
980 | qsort (stack_vars_sorted, n, sizeof (size_t), stack_var_size_cmp); | |
981 | ||
982 | /* Special case: detect when all variables conflict, and thus we can't | |
983 | do anything during the partitioning loop. It isn't uncommon (with | |
984 | C code at least) to declare all variables at the top of the function, | |
985 | and if we're not inlining, then all variables will be in the same scope. | |
986 | Take advantage of very fast libc routines for this scan. */ | |
987 | gcc_assert (sizeof(bool) == sizeof(char)); | |
988 | if (memchr (stack_vars_conflict, false, stack_vars_conflict_alloc) == NULL) | |
989 | return; | |
990 | ||
991 | for (si = 0; si < n; ++si) | |
992 | { | |
993 | size_t i = stack_vars_sorted[si]; | |
994 | HOST_WIDE_INT isize = stack_vars[i].size; | |
995 | HOST_WIDE_INT offset = 0; | |
996 | ||
997 | for (sj = si; sj-- > 0; ) | |
998 | { | |
999 | size_t j = stack_vars_sorted[sj]; | |
1000 | HOST_WIDE_INT jsize = stack_vars[j].size; | |
1001 | unsigned int jalign = stack_vars[j].alignb; | |
1002 | ||
1003 | /* Ignore objects that aren't partition representatives. */ | |
1004 | if (stack_vars[j].representative != j) | |
1005 | continue; | |
1006 | ||
1007 | /* Ignore objects too large for the remaining space. */ | |
1008 | if (isize < jsize) | |
1009 | continue; | |
1010 | ||
1011 | /* Ignore conflicting objects. */ | |
1012 | if (stack_var_conflict_p (i, j)) | |
1013 | continue; | |
1014 | ||
1015 | /* Refine the remaining space check to include alignment. */ | |
1016 | if (offset & (jalign - 1)) | |
1017 | { | |
1018 | HOST_WIDE_INT toff = offset; | |
1019 | toff += jalign - 1; | |
1020 | toff &= -(HOST_WIDE_INT)jalign; | |
1021 | if (isize - (toff - offset) < jsize) | |
1022 | continue; | |
1023 | ||
1024 | isize -= toff - offset; | |
1025 | offset = toff; | |
1026 | } | |
1027 | ||
1028 | /* UNION the objects, placing J at OFFSET. */ | |
1029 | union_stack_vars (i, j, offset); | |
1030 | ||
1031 | isize -= jsize; | |
1032 | if (isize == 0) | |
1033 | break; | |
1034 | } | |
1035 | } | |
55b34b5f | 1036 | |
0b200b80 RG |
1037 | if (optimize) |
1038 | update_alias_info_with_stack_vars (); | |
1f6d3a08 RH |
1039 | } |
1040 | ||
1041 | /* A debugging aid for expand_used_vars. Dump the generated partitions. */ | |
1042 | ||
1043 | static void | |
1044 | dump_stack_var_partition (void) | |
1045 | { | |
1046 | size_t si, i, j, n = stack_vars_num; | |
1047 | ||
1048 | for (si = 0; si < n; ++si) | |
1049 | { | |
1050 | i = stack_vars_sorted[si]; | |
1051 | ||
1052 | /* Skip variables that aren't partition representatives, for now. */ | |
1053 | if (stack_vars[i].representative != i) | |
1054 | continue; | |
1055 | ||
1056 | fprintf (dump_file, "Partition %lu: size " HOST_WIDE_INT_PRINT_DEC | |
1057 | " align %u\n", (unsigned long) i, stack_vars[i].size, | |
1058 | stack_vars[i].alignb); | |
1059 | ||
1060 | for (j = i; j != EOC; j = stack_vars[j].next) | |
1061 | { | |
1062 | fputc ('\t', dump_file); | |
1063 | print_generic_expr (dump_file, stack_vars[j].decl, dump_flags); | |
1064 | fprintf (dump_file, ", offset " HOST_WIDE_INT_PRINT_DEC "\n", | |
1c50a20a | 1065 | stack_vars[j].offset); |
1f6d3a08 RH |
1066 | } |
1067 | } | |
1068 | } | |
1069 | ||
1070 | /* Assign rtl to DECL at frame offset OFFSET. */ | |
1071 | ||
1072 | static void | |
1073 | expand_one_stack_var_at (tree decl, HOST_WIDE_INT offset) | |
1074 | { | |
2ac26e15 L |
1075 | /* Alignment is unsigned. */ |
1076 | unsigned HOST_WIDE_INT align; | |
1f6d3a08 | 1077 | rtx x; |
c22cacf3 | 1078 | |
1f6d3a08 RH |
1079 | /* If this fails, we've overflowed the stack frame. Error nicely? */ |
1080 | gcc_assert (offset == trunc_int_for_mode (offset, Pmode)); | |
1081 | ||
1082 | x = plus_constant (virtual_stack_vars_rtx, offset); | |
4e3825db | 1083 | x = gen_rtx_MEM (DECL_MODE (SSAVAR (decl)), x); |
1f6d3a08 | 1084 | |
4e3825db MM |
1085 | if (TREE_CODE (decl) != SSA_NAME) |
1086 | { | |
1087 | /* Set alignment we actually gave this decl if it isn't an SSA name. | |
1088 | If it is we generate stack slots only accidentally so it isn't as | |
1089 | important, we'll simply use the alignment that is already set. */ | |
1090 | offset -= frame_phase; | |
1091 | align = offset & -offset; | |
1092 | align *= BITS_PER_UNIT; | |
1093 | if (align == 0) | |
1094 | align = STACK_BOUNDARY; | |
1095 | else if (align > MAX_SUPPORTED_STACK_ALIGNMENT) | |
1096 | align = MAX_SUPPORTED_STACK_ALIGNMENT; | |
1097 | ||
1098 | DECL_ALIGN (decl) = align; | |
1099 | DECL_USER_ALIGN (decl) = 0; | |
1100 | } | |
1101 | ||
1102 | set_mem_attributes (x, SSAVAR (decl), true); | |
1103 | set_rtl (decl, x); | |
1f6d3a08 RH |
1104 | } |
1105 | ||
1106 | /* A subroutine of expand_used_vars. Give each partition representative | |
1107 | a unique location within the stack frame. Update each partition member | |
1108 | with that location. */ | |
1109 | ||
1110 | static void | |
7d69de61 | 1111 | expand_stack_vars (bool (*pred) (tree)) |
1f6d3a08 RH |
1112 | { |
1113 | size_t si, i, j, n = stack_vars_num; | |
1114 | ||
1115 | for (si = 0; si < n; ++si) | |
1116 | { | |
1117 | HOST_WIDE_INT offset; | |
1118 | ||
1119 | i = stack_vars_sorted[si]; | |
1120 | ||
1121 | /* Skip variables that aren't partition representatives, for now. */ | |
1122 | if (stack_vars[i].representative != i) | |
1123 | continue; | |
1124 | ||
7d69de61 RH |
1125 | /* Skip variables that have already had rtl assigned. See also |
1126 | add_stack_var where we perpetrate this pc_rtx hack. */ | |
4e3825db MM |
1127 | if ((TREE_CODE (stack_vars[i].decl) == SSA_NAME |
1128 | ? SA.partition_to_pseudo[var_to_partition (SA.map, stack_vars[i].decl)] | |
1129 | : DECL_RTL (stack_vars[i].decl)) != pc_rtx) | |
7d69de61 RH |
1130 | continue; |
1131 | ||
c22cacf3 | 1132 | /* Check the predicate to see whether this variable should be |
7d69de61 RH |
1133 | allocated in this pass. */ |
1134 | if (pred && !pred (stack_vars[i].decl)) | |
1135 | continue; | |
1136 | ||
1f6d3a08 RH |
1137 | offset = alloc_stack_frame_space (stack_vars[i].size, |
1138 | stack_vars[i].alignb); | |
1139 | ||
1140 | /* Create rtl for each variable based on their location within the | |
1141 | partition. */ | |
1142 | for (j = i; j != EOC; j = stack_vars[j].next) | |
f8da8190 AP |
1143 | { |
1144 | gcc_assert (stack_vars[j].offset <= stack_vars[i].size); | |
1145 | expand_one_stack_var_at (stack_vars[j].decl, | |
1146 | stack_vars[j].offset + offset); | |
1147 | } | |
1f6d3a08 RH |
1148 | } |
1149 | } | |
1150 | ||
ff28a94d JH |
1151 | /* Take into account all sizes of partitions and reset DECL_RTLs. */ |
1152 | static HOST_WIDE_INT | |
1153 | account_stack_vars (void) | |
1154 | { | |
1155 | size_t si, j, i, n = stack_vars_num; | |
1156 | HOST_WIDE_INT size = 0; | |
1157 | ||
1158 | for (si = 0; si < n; ++si) | |
1159 | { | |
1160 | i = stack_vars_sorted[si]; | |
1161 | ||
1162 | /* Skip variables that aren't partition representatives, for now. */ | |
1163 | if (stack_vars[i].representative != i) | |
1164 | continue; | |
1165 | ||
1166 | size += stack_vars[i].size; | |
1167 | for (j = i; j != EOC; j = stack_vars[j].next) | |
4e3825db | 1168 | set_rtl (stack_vars[j].decl, NULL); |
ff28a94d JH |
1169 | } |
1170 | return size; | |
1171 | } | |
1172 | ||
1f6d3a08 RH |
1173 | /* A subroutine of expand_one_var. Called to immediately assign rtl |
1174 | to a variable to be allocated in the stack frame. */ | |
1175 | ||
1176 | static void | |
1177 | expand_one_stack_var (tree var) | |
1178 | { | |
1179 | HOST_WIDE_INT size, offset, align; | |
1180 | ||
4e3825db MM |
1181 | size = tree_low_cst (DECL_SIZE_UNIT (SSAVAR (var)), 1); |
1182 | align = get_decl_align_unit (SSAVAR (var)); | |
1f6d3a08 RH |
1183 | offset = alloc_stack_frame_space (size, align); |
1184 | ||
1185 | expand_one_stack_var_at (var, offset); | |
1186 | } | |
1187 | ||
1f6d3a08 RH |
1188 | /* A subroutine of expand_one_var. Called to assign rtl to a VAR_DECL |
1189 | that will reside in a hard register. */ | |
1190 | ||
1191 | static void | |
1192 | expand_one_hard_reg_var (tree var) | |
1193 | { | |
1194 | rest_of_decl_compilation (var, 0, 0); | |
1195 | } | |
1196 | ||
1197 | /* A subroutine of expand_one_var. Called to assign rtl to a VAR_DECL | |
1198 | that will reside in a pseudo register. */ | |
1199 | ||
1200 | static void | |
1201 | expand_one_register_var (tree var) | |
1202 | { | |
4e3825db MM |
1203 | tree decl = SSAVAR (var); |
1204 | tree type = TREE_TYPE (decl); | |
cde0f3fd | 1205 | enum machine_mode reg_mode = promote_decl_mode (decl, NULL); |
1f6d3a08 RH |
1206 | rtx x = gen_reg_rtx (reg_mode); |
1207 | ||
4e3825db | 1208 | set_rtl (var, x); |
1f6d3a08 RH |
1209 | |
1210 | /* Note if the object is a user variable. */ | |
4e3825db MM |
1211 | if (!DECL_ARTIFICIAL (decl)) |
1212 | mark_user_reg (x); | |
1f6d3a08 | 1213 | |
61021c2c | 1214 | if (POINTER_TYPE_P (type)) |
4e3825db | 1215 | mark_reg_pointer (x, TYPE_ALIGN (TREE_TYPE (type))); |
1f6d3a08 RH |
1216 | } |
1217 | ||
1218 | /* A subroutine of expand_one_var. Called to assign rtl to a VAR_DECL that | |
128a79fb | 1219 | has some associated error, e.g. its type is error-mark. We just need |
1f6d3a08 RH |
1220 | to pick something that won't crash the rest of the compiler. */ |
1221 | ||
1222 | static void | |
1223 | expand_one_error_var (tree var) | |
1224 | { | |
1225 | enum machine_mode mode = DECL_MODE (var); | |
1226 | rtx x; | |
1227 | ||
1228 | if (mode == BLKmode) | |
1229 | x = gen_rtx_MEM (BLKmode, const0_rtx); | |
1230 | else if (mode == VOIDmode) | |
1231 | x = const0_rtx; | |
1232 | else | |
1233 | x = gen_reg_rtx (mode); | |
1234 | ||
1235 | SET_DECL_RTL (var, x); | |
1236 | } | |
1237 | ||
c22cacf3 | 1238 | /* A subroutine of expand_one_var. VAR is a variable that will be |
1f6d3a08 RH |
1239 | allocated to the local stack frame. Return true if we wish to |
1240 | add VAR to STACK_VARS so that it will be coalesced with other | |
1241 | variables. Return false to allocate VAR immediately. | |
1242 | ||
1243 | This function is used to reduce the number of variables considered | |
1244 | for coalescing, which reduces the size of the quadratic problem. */ | |
1245 | ||
1246 | static bool | |
1247 | defer_stack_allocation (tree var, bool toplevel) | |
1248 | { | |
7d69de61 RH |
1249 | /* If stack protection is enabled, *all* stack variables must be deferred, |
1250 | so that we can re-order the strings to the top of the frame. */ | |
1251 | if (flag_stack_protect) | |
1252 | return true; | |
1253 | ||
1f6d3a08 RH |
1254 | /* Variables in the outermost scope automatically conflict with |
1255 | every other variable. The only reason to want to defer them | |
1256 | at all is that, after sorting, we can more efficiently pack | |
1257 | small variables in the stack frame. Continue to defer at -O2. */ | |
1258 | if (toplevel && optimize < 2) | |
1259 | return false; | |
1260 | ||
1261 | /* Without optimization, *most* variables are allocated from the | |
1262 | stack, which makes the quadratic problem large exactly when we | |
c22cacf3 | 1263 | want compilation to proceed as quickly as possible. On the |
1f6d3a08 RH |
1264 | other hand, we don't want the function's stack frame size to |
1265 | get completely out of hand. So we avoid adding scalars and | |
1266 | "small" aggregates to the list at all. */ | |
1267 | if (optimize == 0 && tree_low_cst (DECL_SIZE_UNIT (var), 1) < 32) | |
1268 | return false; | |
1269 | ||
1270 | return true; | |
1271 | } | |
1272 | ||
1273 | /* A subroutine of expand_used_vars. Expand one variable according to | |
2a7e31df | 1274 | its flavor. Variables to be placed on the stack are not actually |
ff28a94d JH |
1275 | expanded yet, merely recorded. |
1276 | When REALLY_EXPAND is false, only add stack values to be allocated. | |
1277 | Return stack usage this variable is supposed to take. | |
1278 | */ | |
1f6d3a08 | 1279 | |
ff28a94d JH |
1280 | static HOST_WIDE_INT |
1281 | expand_one_var (tree var, bool toplevel, bool really_expand) | |
1f6d3a08 | 1282 | { |
4e3825db MM |
1283 | tree origvar = var; |
1284 | var = SSAVAR (var); | |
1285 | ||
2e3f842f L |
1286 | if (SUPPORTS_STACK_ALIGNMENT |
1287 | && TREE_TYPE (var) != error_mark_node | |
1288 | && TREE_CODE (var) == VAR_DECL) | |
1289 | { | |
1290 | unsigned int align; | |
1291 | ||
1292 | /* Because we don't know if VAR will be in register or on stack, | |
1293 | we conservatively assume it will be on stack even if VAR is | |
1294 | eventually put into register after RA pass. For non-automatic | |
1295 | variables, which won't be on stack, we collect alignment of | |
1296 | type and ignore user specified alignment. */ | |
1297 | if (TREE_STATIC (var) || DECL_EXTERNAL (var)) | |
ae58e548 JJ |
1298 | align = MINIMUM_ALIGNMENT (TREE_TYPE (var), |
1299 | TYPE_MODE (TREE_TYPE (var)), | |
1300 | TYPE_ALIGN (TREE_TYPE (var))); | |
2e3f842f | 1301 | else |
ae58e548 | 1302 | align = MINIMUM_ALIGNMENT (var, DECL_MODE (var), DECL_ALIGN (var)); |
2e3f842f L |
1303 | |
1304 | if (crtl->stack_alignment_estimated < align) | |
1305 | { | |
1306 | /* stack_alignment_estimated shouldn't change after stack | |
1307 | realign decision made */ | |
1308 | gcc_assert(!crtl->stack_realign_processed); | |
1309 | crtl->stack_alignment_estimated = align; | |
1310 | } | |
1311 | } | |
1312 | ||
4e3825db MM |
1313 | if (TREE_CODE (origvar) == SSA_NAME) |
1314 | { | |
1315 | gcc_assert (TREE_CODE (var) != VAR_DECL | |
1316 | || (!DECL_EXTERNAL (var) | |
1317 | && !DECL_HAS_VALUE_EXPR_P (var) | |
1318 | && !TREE_STATIC (var) | |
4e3825db MM |
1319 | && TREE_TYPE (var) != error_mark_node |
1320 | && !DECL_HARD_REGISTER (var) | |
1321 | && really_expand)); | |
1322 | } | |
1323 | if (TREE_CODE (var) != VAR_DECL && TREE_CODE (origvar) != SSA_NAME) | |
4846b435 | 1324 | ; |
1f6d3a08 RH |
1325 | else if (DECL_EXTERNAL (var)) |
1326 | ; | |
833b3afe | 1327 | else if (DECL_HAS_VALUE_EXPR_P (var)) |
1f6d3a08 RH |
1328 | ; |
1329 | else if (TREE_STATIC (var)) | |
7e8b322a | 1330 | ; |
eb7adebc | 1331 | else if (TREE_CODE (origvar) != SSA_NAME && DECL_RTL_SET_P (var)) |
1f6d3a08 RH |
1332 | ; |
1333 | else if (TREE_TYPE (var) == error_mark_node) | |
ff28a94d JH |
1334 | { |
1335 | if (really_expand) | |
1336 | expand_one_error_var (var); | |
1337 | } | |
4e3825db | 1338 | else if (TREE_CODE (var) == VAR_DECL && DECL_HARD_REGISTER (var)) |
ff28a94d JH |
1339 | { |
1340 | if (really_expand) | |
1341 | expand_one_hard_reg_var (var); | |
1342 | } | |
1f6d3a08 | 1343 | else if (use_register_for_decl (var)) |
ff28a94d JH |
1344 | { |
1345 | if (really_expand) | |
4e3825db | 1346 | expand_one_register_var (origvar); |
ff28a94d | 1347 | } |
1f6d3a08 | 1348 | else if (defer_stack_allocation (var, toplevel)) |
4e3825db | 1349 | add_stack_var (origvar); |
1f6d3a08 | 1350 | else |
ff28a94d | 1351 | { |
bd9f1b4b | 1352 | if (really_expand) |
4e3825db | 1353 | expand_one_stack_var (origvar); |
ff28a94d JH |
1354 | return tree_low_cst (DECL_SIZE_UNIT (var), 1); |
1355 | } | |
1356 | return 0; | |
1f6d3a08 RH |
1357 | } |
1358 | ||
1359 | /* A subroutine of expand_used_vars. Walk down through the BLOCK tree | |
1360 | expanding variables. Those variables that can be put into registers | |
1361 | are allocated pseudos; those that can't are put on the stack. | |
1362 | ||
1363 | TOPLEVEL is true if this is the outermost BLOCK. */ | |
1364 | ||
1365 | static void | |
1366 | expand_used_vars_for_block (tree block, bool toplevel) | |
1367 | { | |
1368 | size_t i, j, old_sv_num, this_sv_num, new_sv_num; | |
1369 | tree t; | |
1370 | ||
1371 | old_sv_num = toplevel ? 0 : stack_vars_num; | |
1372 | ||
1373 | /* Expand all variables at this level. */ | |
1374 | for (t = BLOCK_VARS (block); t ; t = TREE_CHAIN (t)) | |
7e8b322a | 1375 | if (TREE_USED (t)) |
ff28a94d | 1376 | expand_one_var (t, toplevel, true); |
1f6d3a08 RH |
1377 | |
1378 | this_sv_num = stack_vars_num; | |
1379 | ||
1380 | /* Expand all variables at containing levels. */ | |
1381 | for (t = BLOCK_SUBBLOCKS (block); t ; t = BLOCK_CHAIN (t)) | |
1382 | expand_used_vars_for_block (t, false); | |
1383 | ||
1384 | /* Since we do not track exact variable lifetimes (which is not even | |
6fc0bb99 | 1385 | possible for variables whose address escapes), we mirror the block |
1f6d3a08 RH |
1386 | tree in the interference graph. Here we cause all variables at this |
1387 | level, and all sublevels, to conflict. Do make certain that a | |
1388 | variable conflicts with itself. */ | |
1389 | if (old_sv_num < this_sv_num) | |
1390 | { | |
1391 | new_sv_num = stack_vars_num; | |
1392 | resize_stack_vars_conflict (new_sv_num); | |
1393 | ||
1394 | for (i = old_sv_num; i < new_sv_num; ++i) | |
f4a6d54e RH |
1395 | for (j = i < this_sv_num ? i+1 : this_sv_num; j-- > old_sv_num ;) |
1396 | add_stack_var_conflict (i, j); | |
1f6d3a08 RH |
1397 | } |
1398 | } | |
1399 | ||
1400 | /* A subroutine of expand_used_vars. Walk down through the BLOCK tree | |
1401 | and clear TREE_USED on all local variables. */ | |
1402 | ||
1403 | static void | |
1404 | clear_tree_used (tree block) | |
1405 | { | |
1406 | tree t; | |
1407 | ||
1408 | for (t = BLOCK_VARS (block); t ; t = TREE_CHAIN (t)) | |
1409 | /* if (!TREE_STATIC (t) && !DECL_EXTERNAL (t)) */ | |
1410 | TREE_USED (t) = 0; | |
1411 | ||
1412 | for (t = BLOCK_SUBBLOCKS (block); t ; t = BLOCK_CHAIN (t)) | |
1413 | clear_tree_used (t); | |
1414 | } | |
1415 | ||
7d69de61 RH |
1416 | /* Examine TYPE and determine a bit mask of the following features. */ |
1417 | ||
1418 | #define SPCT_HAS_LARGE_CHAR_ARRAY 1 | |
1419 | #define SPCT_HAS_SMALL_CHAR_ARRAY 2 | |
1420 | #define SPCT_HAS_ARRAY 4 | |
1421 | #define SPCT_HAS_AGGREGATE 8 | |
1422 | ||
1423 | static unsigned int | |
1424 | stack_protect_classify_type (tree type) | |
1425 | { | |
1426 | unsigned int ret = 0; | |
1427 | tree t; | |
1428 | ||
1429 | switch (TREE_CODE (type)) | |
1430 | { | |
1431 | case ARRAY_TYPE: | |
1432 | t = TYPE_MAIN_VARIANT (TREE_TYPE (type)); | |
1433 | if (t == char_type_node | |
1434 | || t == signed_char_type_node | |
1435 | || t == unsigned_char_type_node) | |
1436 | { | |
15362b89 JJ |
1437 | unsigned HOST_WIDE_INT max = PARAM_VALUE (PARAM_SSP_BUFFER_SIZE); |
1438 | unsigned HOST_WIDE_INT len; | |
7d69de61 | 1439 | |
15362b89 JJ |
1440 | if (!TYPE_SIZE_UNIT (type) |
1441 | || !host_integerp (TYPE_SIZE_UNIT (type), 1)) | |
1442 | len = max; | |
7d69de61 | 1443 | else |
15362b89 | 1444 | len = tree_low_cst (TYPE_SIZE_UNIT (type), 1); |
7d69de61 RH |
1445 | |
1446 | if (len < max) | |
1447 | ret = SPCT_HAS_SMALL_CHAR_ARRAY | SPCT_HAS_ARRAY; | |
1448 | else | |
1449 | ret = SPCT_HAS_LARGE_CHAR_ARRAY | SPCT_HAS_ARRAY; | |
1450 | } | |
1451 | else | |
1452 | ret = SPCT_HAS_ARRAY; | |
1453 | break; | |
1454 | ||
1455 | case UNION_TYPE: | |
1456 | case QUAL_UNION_TYPE: | |
1457 | case RECORD_TYPE: | |
1458 | ret = SPCT_HAS_AGGREGATE; | |
1459 | for (t = TYPE_FIELDS (type); t ; t = TREE_CHAIN (t)) | |
1460 | if (TREE_CODE (t) == FIELD_DECL) | |
1461 | ret |= stack_protect_classify_type (TREE_TYPE (t)); | |
1462 | break; | |
1463 | ||
1464 | default: | |
1465 | break; | |
1466 | } | |
1467 | ||
1468 | return ret; | |
1469 | } | |
1470 | ||
a4d05547 KH |
1471 | /* Return nonzero if DECL should be segregated into the "vulnerable" upper |
1472 | part of the local stack frame. Remember if we ever return nonzero for | |
7d69de61 RH |
1473 | any variable in this function. The return value is the phase number in |
1474 | which the variable should be allocated. */ | |
1475 | ||
1476 | static int | |
1477 | stack_protect_decl_phase (tree decl) | |
1478 | { | |
1479 | unsigned int bits = stack_protect_classify_type (TREE_TYPE (decl)); | |
1480 | int ret = 0; | |
1481 | ||
1482 | if (bits & SPCT_HAS_SMALL_CHAR_ARRAY) | |
1483 | has_short_buffer = true; | |
1484 | ||
1485 | if (flag_stack_protect == 2) | |
1486 | { | |
1487 | if ((bits & (SPCT_HAS_SMALL_CHAR_ARRAY | SPCT_HAS_LARGE_CHAR_ARRAY)) | |
1488 | && !(bits & SPCT_HAS_AGGREGATE)) | |
1489 | ret = 1; | |
1490 | else if (bits & SPCT_HAS_ARRAY) | |
1491 | ret = 2; | |
1492 | } | |
1493 | else | |
1494 | ret = (bits & SPCT_HAS_LARGE_CHAR_ARRAY) != 0; | |
1495 | ||
1496 | if (ret) | |
1497 | has_protected_decls = true; | |
1498 | ||
1499 | return ret; | |
1500 | } | |
1501 | ||
1502 | /* Two helper routines that check for phase 1 and phase 2. These are used | |
1503 | as callbacks for expand_stack_vars. */ | |
1504 | ||
1505 | static bool | |
1506 | stack_protect_decl_phase_1 (tree decl) | |
1507 | { | |
1508 | return stack_protect_decl_phase (decl) == 1; | |
1509 | } | |
1510 | ||
1511 | static bool | |
1512 | stack_protect_decl_phase_2 (tree decl) | |
1513 | { | |
1514 | return stack_protect_decl_phase (decl) == 2; | |
1515 | } | |
1516 | ||
1517 | /* Ensure that variables in different stack protection phases conflict | |
1518 | so that they are not merged and share the same stack slot. */ | |
1519 | ||
1520 | static void | |
1521 | add_stack_protection_conflicts (void) | |
1522 | { | |
1523 | size_t i, j, n = stack_vars_num; | |
1524 | unsigned char *phase; | |
1525 | ||
1526 | phase = XNEWVEC (unsigned char, n); | |
1527 | for (i = 0; i < n; ++i) | |
1528 | phase[i] = stack_protect_decl_phase (stack_vars[i].decl); | |
1529 | ||
1530 | for (i = 0; i < n; ++i) | |
1531 | { | |
1532 | unsigned char ph_i = phase[i]; | |
1533 | for (j = 0; j < i; ++j) | |
1534 | if (ph_i != phase[j]) | |
1535 | add_stack_var_conflict (i, j); | |
1536 | } | |
1537 | ||
1538 | XDELETEVEC (phase); | |
1539 | } | |
1540 | ||
1541 | /* Create a decl for the guard at the top of the stack frame. */ | |
1542 | ||
1543 | static void | |
1544 | create_stack_guard (void) | |
1545 | { | |
c2255bc4 AH |
1546 | tree guard = build_decl (DECL_SOURCE_LOCATION (current_function_decl), |
1547 | VAR_DECL, NULL, ptr_type_node); | |
7d69de61 RH |
1548 | TREE_THIS_VOLATILE (guard) = 1; |
1549 | TREE_USED (guard) = 1; | |
1550 | expand_one_stack_var (guard); | |
cb91fab0 | 1551 | crtl->stack_protect_guard = guard; |
7d69de61 RH |
1552 | } |
1553 | ||
ff28a94d JH |
1554 | /* A subroutine of expand_used_vars. Walk down through the BLOCK tree |
1555 | expanding variables. Those variables that can be put into registers | |
1556 | are allocated pseudos; those that can't are put on the stack. | |
1557 | ||
1558 | TOPLEVEL is true if this is the outermost BLOCK. */ | |
1559 | ||
1560 | static HOST_WIDE_INT | |
1561 | account_used_vars_for_block (tree block, bool toplevel) | |
1562 | { | |
1563 | size_t i, j, old_sv_num, this_sv_num, new_sv_num; | |
1564 | tree t; | |
1565 | HOST_WIDE_INT size = 0; | |
1566 | ||
1567 | old_sv_num = toplevel ? 0 : stack_vars_num; | |
1568 | ||
1569 | /* Expand all variables at this level. */ | |
1570 | for (t = BLOCK_VARS (block); t ; t = TREE_CHAIN (t)) | |
1571 | if (TREE_USED (t)) | |
1572 | size += expand_one_var (t, toplevel, false); | |
1573 | ||
1574 | this_sv_num = stack_vars_num; | |
1575 | ||
1576 | /* Expand all variables at containing levels. */ | |
1577 | for (t = BLOCK_SUBBLOCKS (block); t ; t = BLOCK_CHAIN (t)) | |
1578 | size += account_used_vars_for_block (t, false); | |
1579 | ||
1580 | /* Since we do not track exact variable lifetimes (which is not even | |
1581 | possible for variables whose address escapes), we mirror the block | |
1582 | tree in the interference graph. Here we cause all variables at this | |
1583 | level, and all sublevels, to conflict. Do make certain that a | |
1584 | variable conflicts with itself. */ | |
1585 | if (old_sv_num < this_sv_num) | |
1586 | { | |
1587 | new_sv_num = stack_vars_num; | |
1588 | resize_stack_vars_conflict (new_sv_num); | |
1589 | ||
1590 | for (i = old_sv_num; i < new_sv_num; ++i) | |
1591 | for (j = i < this_sv_num ? i+1 : this_sv_num; j-- > old_sv_num ;) | |
1592 | add_stack_var_conflict (i, j); | |
1593 | } | |
1594 | return size; | |
1595 | } | |
1596 | ||
1597 | /* Prepare for expanding variables. */ | |
1598 | static void | |
1599 | init_vars_expansion (void) | |
1600 | { | |
1601 | tree t; | |
cb91fab0 JH |
1602 | /* Set TREE_USED on all variables in the local_decls. */ |
1603 | for (t = cfun->local_decls; t; t = TREE_CHAIN (t)) | |
ff28a94d JH |
1604 | TREE_USED (TREE_VALUE (t)) = 1; |
1605 | ||
1606 | /* Clear TREE_USED on all variables associated with a block scope. */ | |
1607 | clear_tree_used (DECL_INITIAL (current_function_decl)); | |
1608 | ||
1609 | /* Initialize local stack smashing state. */ | |
1610 | has_protected_decls = false; | |
1611 | has_short_buffer = false; | |
1612 | } | |
1613 | ||
1614 | /* Free up stack variable graph data. */ | |
1615 | static void | |
1616 | fini_vars_expansion (void) | |
1617 | { | |
1618 | XDELETEVEC (stack_vars); | |
1619 | XDELETEVEC (stack_vars_sorted); | |
1620 | XDELETEVEC (stack_vars_conflict); | |
1621 | stack_vars = NULL; | |
1622 | stack_vars_alloc = stack_vars_num = 0; | |
1623 | stack_vars_conflict = NULL; | |
1624 | stack_vars_conflict_alloc = 0; | |
1625 | } | |
1626 | ||
b5a430f3 SB |
1627 | /* Make a fair guess for the size of the stack frame of the current |
1628 | function. This doesn't have to be exact, the result is only used | |
1629 | in the inline heuristics. So we don't want to run the full stack | |
1630 | var packing algorithm (which is quadratic in the number of stack | |
1631 | vars). Instead, we calculate the total size of all stack vars. | |
1632 | This turns out to be a pretty fair estimate -- packing of stack | |
1633 | vars doesn't happen very often. */ | |
1634 | ||
ff28a94d JH |
1635 | HOST_WIDE_INT |
1636 | estimated_stack_frame_size (void) | |
1637 | { | |
1638 | HOST_WIDE_INT size = 0; | |
b5a430f3 | 1639 | size_t i; |
ff28a94d JH |
1640 | tree t, outer_block = DECL_INITIAL (current_function_decl); |
1641 | ||
1642 | init_vars_expansion (); | |
1643 | ||
cb91fab0 | 1644 | for (t = cfun->local_decls; t; t = TREE_CHAIN (t)) |
ff28a94d JH |
1645 | { |
1646 | tree var = TREE_VALUE (t); | |
1647 | ||
1648 | if (TREE_USED (var)) | |
1649 | size += expand_one_var (var, true, false); | |
1650 | TREE_USED (var) = 1; | |
1651 | } | |
1652 | size += account_used_vars_for_block (outer_block, true); | |
b5a430f3 | 1653 | |
ff28a94d JH |
1654 | if (stack_vars_num > 0) |
1655 | { | |
b5a430f3 SB |
1656 | /* Fake sorting the stack vars for account_stack_vars (). */ |
1657 | stack_vars_sorted = XNEWVEC (size_t, stack_vars_num); | |
1658 | for (i = 0; i < stack_vars_num; ++i) | |
1659 | stack_vars_sorted[i] = i; | |
ff28a94d JH |
1660 | size += account_stack_vars (); |
1661 | fini_vars_expansion (); | |
1662 | } | |
b5a430f3 | 1663 | |
ff28a94d JH |
1664 | return size; |
1665 | } | |
1666 | ||
1f6d3a08 | 1667 | /* Expand all variables used in the function. */ |
727a31fa RH |
1668 | |
1669 | static void | |
1670 | expand_used_vars (void) | |
1671 | { | |
802e9f8e | 1672 | tree t, next, outer_block = DECL_INITIAL (current_function_decl); |
4e3825db | 1673 | unsigned i; |
727a31fa | 1674 | |
1f6d3a08 RH |
1675 | /* Compute the phase of the stack frame for this function. */ |
1676 | { | |
1677 | int align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT; | |
1678 | int off = STARTING_FRAME_OFFSET % align; | |
1679 | frame_phase = off ? align - off : 0; | |
1680 | } | |
727a31fa | 1681 | |
ff28a94d | 1682 | init_vars_expansion (); |
7d69de61 | 1683 | |
4e3825db MM |
1684 | for (i = 0; i < SA.map->num_partitions; i++) |
1685 | { | |
1686 | tree var = partition_to_var (SA.map, i); | |
1687 | ||
1688 | gcc_assert (is_gimple_reg (var)); | |
1689 | if (TREE_CODE (SSA_NAME_VAR (var)) == VAR_DECL) | |
1690 | expand_one_var (var, true, true); | |
1691 | else | |
1692 | { | |
1693 | /* This is a PARM_DECL or RESULT_DECL. For those partitions that | |
1694 | contain the default def (representing the parm or result itself) | |
1695 | we don't do anything here. But those which don't contain the | |
1696 | default def (representing a temporary based on the parm/result) | |
1697 | we need to allocate space just like for normal VAR_DECLs. */ | |
1698 | if (!bitmap_bit_p (SA.partition_has_default_def, i)) | |
1699 | { | |
1700 | expand_one_var (var, true, true); | |
1701 | gcc_assert (SA.partition_to_pseudo[i]); | |
1702 | } | |
1703 | } | |
1704 | } | |
1705 | ||
cb91fab0 | 1706 | /* At this point all variables on the local_decls with TREE_USED |
1f6d3a08 | 1707 | set are not associated with any block scope. Lay them out. */ |
802e9f8e JJ |
1708 | t = cfun->local_decls; |
1709 | cfun->local_decls = NULL_TREE; | |
1710 | for (; t; t = next) | |
1f6d3a08 RH |
1711 | { |
1712 | tree var = TREE_VALUE (t); | |
1713 | bool expand_now = false; | |
1714 | ||
802e9f8e JJ |
1715 | next = TREE_CHAIN (t); |
1716 | ||
4e3825db MM |
1717 | /* Expanded above already. */ |
1718 | if (is_gimple_reg (var)) | |
eb7adebc MM |
1719 | { |
1720 | TREE_USED (var) = 0; | |
1721 | ggc_free (t); | |
1722 | continue; | |
1723 | } | |
1f6d3a08 RH |
1724 | /* We didn't set a block for static or extern because it's hard |
1725 | to tell the difference between a global variable (re)declared | |
1726 | in a local scope, and one that's really declared there to | |
1727 | begin with. And it doesn't really matter much, since we're | |
1728 | not giving them stack space. Expand them now. */ | |
4e3825db | 1729 | else if (TREE_STATIC (var) || DECL_EXTERNAL (var)) |
1f6d3a08 RH |
1730 | expand_now = true; |
1731 | ||
1732 | /* If the variable is not associated with any block, then it | |
1733 | was created by the optimizers, and could be live anywhere | |
1734 | in the function. */ | |
1735 | else if (TREE_USED (var)) | |
1736 | expand_now = true; | |
1737 | ||
1738 | /* Finally, mark all variables on the list as used. We'll use | |
1739 | this in a moment when we expand those associated with scopes. */ | |
1740 | TREE_USED (var) = 1; | |
1741 | ||
1742 | if (expand_now) | |
802e9f8e JJ |
1743 | { |
1744 | expand_one_var (var, true, true); | |
1745 | if (DECL_ARTIFICIAL (var) && !DECL_IGNORED_P (var)) | |
1746 | { | |
1747 | rtx rtl = DECL_RTL_IF_SET (var); | |
1748 | ||
1749 | /* Keep artificial non-ignored vars in cfun->local_decls | |
1750 | chain until instantiate_decls. */ | |
1751 | if (rtl && (MEM_P (rtl) || GET_CODE (rtl) == CONCAT)) | |
1752 | { | |
1753 | TREE_CHAIN (t) = cfun->local_decls; | |
1754 | cfun->local_decls = t; | |
1755 | continue; | |
1756 | } | |
1757 | } | |
1758 | } | |
1759 | ||
1760 | ggc_free (t); | |
1f6d3a08 | 1761 | } |
1f6d3a08 RH |
1762 | |
1763 | /* At this point, all variables within the block tree with TREE_USED | |
1764 | set are actually used by the optimized function. Lay them out. */ | |
1765 | expand_used_vars_for_block (outer_block, true); | |
1766 | ||
1767 | if (stack_vars_num > 0) | |
1768 | { | |
1769 | /* Due to the way alias sets work, no variables with non-conflicting | |
c22cacf3 | 1770 | alias sets may be assigned the same address. Add conflicts to |
1f6d3a08 RH |
1771 | reflect this. */ |
1772 | add_alias_set_conflicts (); | |
1773 | ||
c22cacf3 | 1774 | /* If stack protection is enabled, we don't share space between |
7d69de61 RH |
1775 | vulnerable data and non-vulnerable data. */ |
1776 | if (flag_stack_protect) | |
1777 | add_stack_protection_conflicts (); | |
1778 | ||
c22cacf3 | 1779 | /* Now that we have collected all stack variables, and have computed a |
1f6d3a08 RH |
1780 | minimal interference graph, attempt to save some stack space. */ |
1781 | partition_stack_vars (); | |
1782 | if (dump_file) | |
1783 | dump_stack_var_partition (); | |
7d69de61 RH |
1784 | } |
1785 | ||
1786 | /* There are several conditions under which we should create a | |
1787 | stack guard: protect-all, alloca used, protected decls present. */ | |
1788 | if (flag_stack_protect == 2 | |
1789 | || (flag_stack_protect | |
e3b5732b | 1790 | && (cfun->calls_alloca || has_protected_decls))) |
7d69de61 | 1791 | create_stack_guard (); |
1f6d3a08 | 1792 | |
7d69de61 RH |
1793 | /* Assign rtl to each variable based on these partitions. */ |
1794 | if (stack_vars_num > 0) | |
1795 | { | |
1796 | /* Reorder decls to be protected by iterating over the variables | |
1797 | array multiple times, and allocating out of each phase in turn. */ | |
c22cacf3 | 1798 | /* ??? We could probably integrate this into the qsort we did |
7d69de61 RH |
1799 | earlier, such that we naturally see these variables first, |
1800 | and thus naturally allocate things in the right order. */ | |
1801 | if (has_protected_decls) | |
1802 | { | |
1803 | /* Phase 1 contains only character arrays. */ | |
1804 | expand_stack_vars (stack_protect_decl_phase_1); | |
1805 | ||
1806 | /* Phase 2 contains other kinds of arrays. */ | |
1807 | if (flag_stack_protect == 2) | |
1808 | expand_stack_vars (stack_protect_decl_phase_2); | |
1809 | } | |
1810 | ||
1811 | expand_stack_vars (NULL); | |
1f6d3a08 | 1812 | |
ff28a94d | 1813 | fini_vars_expansion (); |
1f6d3a08 RH |
1814 | } |
1815 | ||
1816 | /* If the target requires that FRAME_OFFSET be aligned, do it. */ | |
1817 | if (STACK_ALIGNMENT_NEEDED) | |
1818 | { | |
1819 | HOST_WIDE_INT align = PREFERRED_STACK_BOUNDARY / BITS_PER_UNIT; | |
1820 | if (!FRAME_GROWS_DOWNWARD) | |
1821 | frame_offset += align - 1; | |
1822 | frame_offset &= -align; | |
1823 | } | |
727a31fa RH |
1824 | } |
1825 | ||
1826 | ||
b7211528 SB |
1827 | /* If we need to produce a detailed dump, print the tree representation |
1828 | for STMT to the dump file. SINCE is the last RTX after which the RTL | |
1829 | generated for STMT should have been appended. */ | |
1830 | ||
1831 | static void | |
726a989a | 1832 | maybe_dump_rtl_for_gimple_stmt (gimple stmt, rtx since) |
b7211528 SB |
1833 | { |
1834 | if (dump_file && (dump_flags & TDF_DETAILS)) | |
1835 | { | |
1836 | fprintf (dump_file, "\n;; "); | |
726a989a | 1837 | print_gimple_stmt (dump_file, stmt, 0, TDF_SLIM); |
b7211528 SB |
1838 | fprintf (dump_file, "\n"); |
1839 | ||
1840 | print_rtl (dump_file, since ? NEXT_INSN (since) : since); | |
1841 | } | |
1842 | } | |
1843 | ||
8b11009b ZD |
1844 | /* Maps the blocks that do not contain tree labels to rtx labels. */ |
1845 | ||
1846 | static struct pointer_map_t *lab_rtx_for_bb; | |
1847 | ||
a9b77cd1 ZD |
1848 | /* Returns the label_rtx expression for a label starting basic block BB. */ |
1849 | ||
1850 | static rtx | |
726a989a | 1851 | label_rtx_for_bb (basic_block bb ATTRIBUTE_UNUSED) |
a9b77cd1 | 1852 | { |
726a989a RB |
1853 | gimple_stmt_iterator gsi; |
1854 | tree lab; | |
1855 | gimple lab_stmt; | |
8b11009b | 1856 | void **elt; |
a9b77cd1 ZD |
1857 | |
1858 | if (bb->flags & BB_RTL) | |
1859 | return block_label (bb); | |
1860 | ||
8b11009b ZD |
1861 | elt = pointer_map_contains (lab_rtx_for_bb, bb); |
1862 | if (elt) | |
ae50c0cb | 1863 | return (rtx) *elt; |
8b11009b ZD |
1864 | |
1865 | /* Find the tree label if it is present. */ | |
1866 | ||
726a989a | 1867 | for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) |
a9b77cd1 | 1868 | { |
726a989a RB |
1869 | lab_stmt = gsi_stmt (gsi); |
1870 | if (gimple_code (lab_stmt) != GIMPLE_LABEL) | |
a9b77cd1 ZD |
1871 | break; |
1872 | ||
726a989a | 1873 | lab = gimple_label_label (lab_stmt); |
a9b77cd1 ZD |
1874 | if (DECL_NONLOCAL (lab)) |
1875 | break; | |
1876 | ||
1877 | return label_rtx (lab); | |
1878 | } | |
1879 | ||
8b11009b ZD |
1880 | elt = pointer_map_insert (lab_rtx_for_bb, bb); |
1881 | *elt = gen_label_rtx (); | |
ae50c0cb | 1882 | return (rtx) *elt; |
a9b77cd1 ZD |
1883 | } |
1884 | ||
726a989a | 1885 | |
529ff441 MM |
1886 | /* A subroutine of expand_gimple_cond. Given E, a fallthrough edge |
1887 | of a basic block where we just expanded the conditional at the end, | |
1888 | possibly clean up the CFG and instruction sequence. */ | |
1889 | ||
1890 | static void | |
1891 | maybe_cleanup_end_of_block (edge e) | |
1892 | { | |
1893 | /* Special case: when jumpif decides that the condition is | |
1894 | trivial it emits an unconditional jump (and the necessary | |
1895 | barrier). But we still have two edges, the fallthru one is | |
1896 | wrong. purge_dead_edges would clean this up later. Unfortunately | |
1897 | we have to insert insns (and split edges) before | |
1898 | find_many_sub_basic_blocks and hence before purge_dead_edges. | |
1899 | But splitting edges might create new blocks which depend on the | |
1900 | fact that if there are two edges there's no barrier. So the | |
1901 | barrier would get lost and verify_flow_info would ICE. Instead | |
1902 | of auditing all edge splitters to care for the barrier (which | |
1903 | normally isn't there in a cleaned CFG), fix it here. */ | |
1904 | if (BARRIER_P (get_last_insn ())) | |
1905 | { | |
1906 | basic_block bb = e->src; | |
1907 | rtx insn; | |
1908 | remove_edge (e); | |
1909 | /* Now, we have a single successor block, if we have insns to | |
1910 | insert on the remaining edge we potentially will insert | |
1911 | it at the end of this block (if the dest block isn't feasible) | |
1912 | in order to avoid splitting the edge. This insertion will take | |
1913 | place in front of the last jump. But we might have emitted | |
1914 | multiple jumps (conditional and one unconditional) to the | |
1915 | same destination. Inserting in front of the last one then | |
1916 | is a problem. See PR 40021. We fix this by deleting all | |
1917 | jumps except the last unconditional one. */ | |
1918 | insn = PREV_INSN (get_last_insn ()); | |
1919 | /* Make sure we have an unconditional jump. Otherwise we're | |
1920 | confused. */ | |
1921 | gcc_assert (JUMP_P (insn) && !any_condjump_p (insn)); | |
1922 | for (insn = PREV_INSN (insn); insn != BB_HEAD (bb);) | |
1923 | { | |
1924 | insn = PREV_INSN (insn); | |
1925 | if (JUMP_P (NEXT_INSN (insn))) | |
1926 | delete_insn (NEXT_INSN (insn)); | |
1927 | } | |
1928 | } | |
1929 | } | |
1930 | ||
1931 | ||
726a989a | 1932 | /* A subroutine of expand_gimple_basic_block. Expand one GIMPLE_COND. |
80c7a9eb RH |
1933 | Returns a new basic block if we've terminated the current basic |
1934 | block and created a new one. */ | |
1935 | ||
1936 | static basic_block | |
726a989a | 1937 | expand_gimple_cond (basic_block bb, gimple stmt) |
80c7a9eb RH |
1938 | { |
1939 | basic_block new_bb, dest; | |
1940 | edge new_edge; | |
1941 | edge true_edge; | |
1942 | edge false_edge; | |
726a989a | 1943 | tree pred = gimple_cond_pred_to_tree (stmt); |
b7211528 SB |
1944 | rtx last2, last; |
1945 | ||
1946 | last2 = last = get_last_insn (); | |
80c7a9eb RH |
1947 | |
1948 | extract_true_false_edges_from_block (bb, &true_edge, &false_edge); | |
726a989a | 1949 | if (gimple_has_location (stmt)) |
80c7a9eb | 1950 | { |
726a989a RB |
1951 | set_curr_insn_source_location (gimple_location (stmt)); |
1952 | set_curr_insn_block (gimple_block (stmt)); | |
80c7a9eb RH |
1953 | } |
1954 | ||
1955 | /* These flags have no purpose in RTL land. */ | |
1956 | true_edge->flags &= ~EDGE_TRUE_VALUE; | |
1957 | false_edge->flags &= ~EDGE_FALSE_VALUE; | |
1958 | ||
1959 | /* We can either have a pure conditional jump with one fallthru edge or | |
1960 | two-way jump that needs to be decomposed into two basic blocks. */ | |
a9b77cd1 | 1961 | if (false_edge->dest == bb->next_bb) |
80c7a9eb | 1962 | { |
a9b77cd1 | 1963 | jumpif (pred, label_rtx_for_bb (true_edge->dest)); |
10d22567 | 1964 | add_reg_br_prob_note (last, true_edge->probability); |
726a989a | 1965 | maybe_dump_rtl_for_gimple_stmt (stmt, last); |
a9b77cd1 | 1966 | if (true_edge->goto_locus) |
7241571e JJ |
1967 | { |
1968 | set_curr_insn_source_location (true_edge->goto_locus); | |
1969 | set_curr_insn_block (true_edge->goto_block); | |
1970 | true_edge->goto_locus = curr_insn_locator (); | |
1971 | } | |
1972 | true_edge->goto_block = NULL; | |
a9b77cd1 | 1973 | false_edge->flags |= EDGE_FALLTHRU; |
726a989a | 1974 | ggc_free (pred); |
529ff441 | 1975 | maybe_cleanup_end_of_block (false_edge); |
80c7a9eb RH |
1976 | return NULL; |
1977 | } | |
a9b77cd1 | 1978 | if (true_edge->dest == bb->next_bb) |
80c7a9eb | 1979 | { |
a9b77cd1 | 1980 | jumpifnot (pred, label_rtx_for_bb (false_edge->dest)); |
10d22567 | 1981 | add_reg_br_prob_note (last, false_edge->probability); |
726a989a | 1982 | maybe_dump_rtl_for_gimple_stmt (stmt, last); |
a9b77cd1 | 1983 | if (false_edge->goto_locus) |
7241571e JJ |
1984 | { |
1985 | set_curr_insn_source_location (false_edge->goto_locus); | |
1986 | set_curr_insn_block (false_edge->goto_block); | |
1987 | false_edge->goto_locus = curr_insn_locator (); | |
1988 | } | |
1989 | false_edge->goto_block = NULL; | |
a9b77cd1 | 1990 | true_edge->flags |= EDGE_FALLTHRU; |
726a989a | 1991 | ggc_free (pred); |
529ff441 | 1992 | maybe_cleanup_end_of_block (true_edge); |
80c7a9eb RH |
1993 | return NULL; |
1994 | } | |
80c7a9eb | 1995 | |
a9b77cd1 | 1996 | jumpif (pred, label_rtx_for_bb (true_edge->dest)); |
10d22567 | 1997 | add_reg_br_prob_note (last, true_edge->probability); |
80c7a9eb | 1998 | last = get_last_insn (); |
7241571e JJ |
1999 | if (false_edge->goto_locus) |
2000 | { | |
2001 | set_curr_insn_source_location (false_edge->goto_locus); | |
2002 | set_curr_insn_block (false_edge->goto_block); | |
2003 | false_edge->goto_locus = curr_insn_locator (); | |
2004 | } | |
2005 | false_edge->goto_block = NULL; | |
a9b77cd1 | 2006 | emit_jump (label_rtx_for_bb (false_edge->dest)); |
80c7a9eb RH |
2007 | |
2008 | BB_END (bb) = last; | |
2009 | if (BARRIER_P (BB_END (bb))) | |
2010 | BB_END (bb) = PREV_INSN (BB_END (bb)); | |
2011 | update_bb_for_insn (bb); | |
2012 | ||
2013 | new_bb = create_basic_block (NEXT_INSN (last), get_last_insn (), bb); | |
2014 | dest = false_edge->dest; | |
2015 | redirect_edge_succ (false_edge, new_bb); | |
2016 | false_edge->flags |= EDGE_FALLTHRU; | |
2017 | new_bb->count = false_edge->count; | |
2018 | new_bb->frequency = EDGE_FREQUENCY (false_edge); | |
2019 | new_edge = make_edge (new_bb, dest, 0); | |
2020 | new_edge->probability = REG_BR_PROB_BASE; | |
2021 | new_edge->count = new_bb->count; | |
2022 | if (BARRIER_P (BB_END (new_bb))) | |
2023 | BB_END (new_bb) = PREV_INSN (BB_END (new_bb)); | |
2024 | update_bb_for_insn (new_bb); | |
2025 | ||
726a989a | 2026 | maybe_dump_rtl_for_gimple_stmt (stmt, last2); |
c22cacf3 | 2027 | |
7787b4aa JJ |
2028 | if (true_edge->goto_locus) |
2029 | { | |
2030 | set_curr_insn_source_location (true_edge->goto_locus); | |
2031 | set_curr_insn_block (true_edge->goto_block); | |
2032 | true_edge->goto_locus = curr_insn_locator (); | |
2033 | } | |
2034 | true_edge->goto_block = NULL; | |
2035 | ||
726a989a | 2036 | ggc_free (pred); |
80c7a9eb RH |
2037 | return new_bb; |
2038 | } | |
2039 | ||
726a989a | 2040 | /* A subroutine of expand_gimple_basic_block. Expand one GIMPLE_CALL |
224e770b RH |
2041 | that has CALL_EXPR_TAILCALL set. Returns non-null if we actually |
2042 | generated a tail call (something that might be denied by the ABI | |
cea49550 RH |
2043 | rules governing the call; see calls.c). |
2044 | ||
2045 | Sets CAN_FALLTHRU if we generated a *conditional* tail call, and | |
2046 | can still reach the rest of BB. The case here is __builtin_sqrt, | |
2047 | where the NaN result goes through the external function (with a | |
2048 | tailcall) and the normal result happens via a sqrt instruction. */ | |
80c7a9eb RH |
2049 | |
2050 | static basic_block | |
726a989a | 2051 | expand_gimple_tailcall (basic_block bb, gimple stmt, bool *can_fallthru) |
80c7a9eb | 2052 | { |
b7211528 | 2053 | rtx last2, last; |
224e770b | 2054 | edge e; |
628f6a4e | 2055 | edge_iterator ei; |
224e770b RH |
2056 | int probability; |
2057 | gcov_type count; | |
726a989a | 2058 | tree stmt_tree = gimple_to_tree (stmt); |
80c7a9eb | 2059 | |
b7211528 SB |
2060 | last2 = last = get_last_insn (); |
2061 | ||
726a989a RB |
2062 | expand_expr_stmt (stmt_tree); |
2063 | ||
2064 | release_stmt_tree (stmt, stmt_tree); | |
80c7a9eb RH |
2065 | |
2066 | for (last = NEXT_INSN (last); last; last = NEXT_INSN (last)) | |
224e770b RH |
2067 | if (CALL_P (last) && SIBLING_CALL_P (last)) |
2068 | goto found; | |
80c7a9eb | 2069 | |
726a989a | 2070 | maybe_dump_rtl_for_gimple_stmt (stmt, last2); |
b7211528 | 2071 | |
cea49550 | 2072 | *can_fallthru = true; |
224e770b | 2073 | return NULL; |
80c7a9eb | 2074 | |
224e770b RH |
2075 | found: |
2076 | /* ??? Wouldn't it be better to just reset any pending stack adjust? | |
2077 | Any instructions emitted here are about to be deleted. */ | |
2078 | do_pending_stack_adjust (); | |
2079 | ||
2080 | /* Remove any non-eh, non-abnormal edges that don't go to exit. */ | |
2081 | /* ??? I.e. the fallthrough edge. HOWEVER! If there were to be | |
2082 | EH or abnormal edges, we shouldn't have created a tail call in | |
2083 | the first place. So it seems to me we should just be removing | |
2084 | all edges here, or redirecting the existing fallthru edge to | |
2085 | the exit block. */ | |
2086 | ||
224e770b RH |
2087 | probability = 0; |
2088 | count = 0; | |
224e770b | 2089 | |
628f6a4e BE |
2090 | for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); ) |
2091 | { | |
224e770b RH |
2092 | if (!(e->flags & (EDGE_ABNORMAL | EDGE_EH))) |
2093 | { | |
2094 | if (e->dest != EXIT_BLOCK_PTR) | |
80c7a9eb | 2095 | { |
224e770b RH |
2096 | e->dest->count -= e->count; |
2097 | e->dest->frequency -= EDGE_FREQUENCY (e); | |
2098 | if (e->dest->count < 0) | |
c22cacf3 | 2099 | e->dest->count = 0; |
224e770b | 2100 | if (e->dest->frequency < 0) |
c22cacf3 | 2101 | e->dest->frequency = 0; |
80c7a9eb | 2102 | } |
224e770b RH |
2103 | count += e->count; |
2104 | probability += e->probability; | |
2105 | remove_edge (e); | |
80c7a9eb | 2106 | } |
628f6a4e BE |
2107 | else |
2108 | ei_next (&ei); | |
80c7a9eb RH |
2109 | } |
2110 | ||
224e770b RH |
2111 | /* This is somewhat ugly: the call_expr expander often emits instructions |
2112 | after the sibcall (to perform the function return). These confuse the | |
12eff7b7 | 2113 | find_many_sub_basic_blocks code, so we need to get rid of these. */ |
224e770b | 2114 | last = NEXT_INSN (last); |
341c100f | 2115 | gcc_assert (BARRIER_P (last)); |
cea49550 RH |
2116 | |
2117 | *can_fallthru = false; | |
224e770b RH |
2118 | while (NEXT_INSN (last)) |
2119 | { | |
2120 | /* For instance an sqrt builtin expander expands if with | |
2121 | sibcall in the then and label for `else`. */ | |
2122 | if (LABEL_P (NEXT_INSN (last))) | |
cea49550 RH |
2123 | { |
2124 | *can_fallthru = true; | |
2125 | break; | |
2126 | } | |
224e770b RH |
2127 | delete_insn (NEXT_INSN (last)); |
2128 | } | |
2129 | ||
2130 | e = make_edge (bb, EXIT_BLOCK_PTR, EDGE_ABNORMAL | EDGE_SIBCALL); | |
2131 | e->probability += probability; | |
2132 | e->count += count; | |
2133 | BB_END (bb) = last; | |
2134 | update_bb_for_insn (bb); | |
2135 | ||
2136 | if (NEXT_INSN (last)) | |
2137 | { | |
2138 | bb = create_basic_block (NEXT_INSN (last), get_last_insn (), bb); | |
2139 | ||
2140 | last = BB_END (bb); | |
2141 | if (BARRIER_P (last)) | |
2142 | BB_END (bb) = PREV_INSN (last); | |
2143 | } | |
2144 | ||
726a989a | 2145 | maybe_dump_rtl_for_gimple_stmt (stmt, last2); |
b7211528 | 2146 | |
224e770b | 2147 | return bb; |
80c7a9eb RH |
2148 | } |
2149 | ||
242229bb JH |
2150 | /* Expand basic block BB from GIMPLE trees to RTL. */ |
2151 | ||
2152 | static basic_block | |
10d22567 | 2153 | expand_gimple_basic_block (basic_block bb) |
242229bb | 2154 | { |
726a989a RB |
2155 | gimple_stmt_iterator gsi; |
2156 | gimple_seq stmts; | |
2157 | gimple stmt = NULL; | |
242229bb JH |
2158 | rtx note, last; |
2159 | edge e; | |
628f6a4e | 2160 | edge_iterator ei; |
8b11009b | 2161 | void **elt; |
242229bb JH |
2162 | |
2163 | if (dump_file) | |
726a989a RB |
2164 | fprintf (dump_file, "\n;; Generating RTL for gimple basic block %d\n", |
2165 | bb->index); | |
2166 | ||
2167 | /* Note that since we are now transitioning from GIMPLE to RTL, we | |
2168 | cannot use the gsi_*_bb() routines because they expect the basic | |
2169 | block to be in GIMPLE, instead of RTL. Therefore, we need to | |
2170 | access the BB sequence directly. */ | |
2171 | stmts = bb_seq (bb); | |
2172 | bb->il.gimple = NULL; | |
bf08ebeb | 2173 | rtl_profile_for_bb (bb); |
5e2d947c JH |
2174 | init_rtl_bb_info (bb); |
2175 | bb->flags |= BB_RTL; | |
2176 | ||
a9b77cd1 ZD |
2177 | /* Remove the RETURN_EXPR if we may fall though to the exit |
2178 | instead. */ | |
726a989a RB |
2179 | gsi = gsi_last (stmts); |
2180 | if (!gsi_end_p (gsi) | |
2181 | && gimple_code (gsi_stmt (gsi)) == GIMPLE_RETURN) | |
a9b77cd1 | 2182 | { |
726a989a | 2183 | gimple ret_stmt = gsi_stmt (gsi); |
a9b77cd1 ZD |
2184 | |
2185 | gcc_assert (single_succ_p (bb)); | |
2186 | gcc_assert (single_succ (bb) == EXIT_BLOCK_PTR); | |
2187 | ||
2188 | if (bb->next_bb == EXIT_BLOCK_PTR | |
726a989a | 2189 | && !gimple_return_retval (ret_stmt)) |
a9b77cd1 | 2190 | { |
726a989a | 2191 | gsi_remove (&gsi, false); |
a9b77cd1 ZD |
2192 | single_succ_edge (bb)->flags |= EDGE_FALLTHRU; |
2193 | } | |
2194 | } | |
2195 | ||
726a989a RB |
2196 | gsi = gsi_start (stmts); |
2197 | if (!gsi_end_p (gsi)) | |
8b11009b | 2198 | { |
726a989a RB |
2199 | stmt = gsi_stmt (gsi); |
2200 | if (gimple_code (stmt) != GIMPLE_LABEL) | |
2201 | stmt = NULL; | |
8b11009b | 2202 | } |
242229bb | 2203 | |
8b11009b ZD |
2204 | elt = pointer_map_contains (lab_rtx_for_bb, bb); |
2205 | ||
2206 | if (stmt || elt) | |
242229bb JH |
2207 | { |
2208 | last = get_last_insn (); | |
2209 | ||
8b11009b ZD |
2210 | if (stmt) |
2211 | { | |
726a989a RB |
2212 | tree stmt_tree = gimple_to_tree (stmt); |
2213 | expand_expr_stmt (stmt_tree); | |
2214 | release_stmt_tree (stmt, stmt_tree); | |
2215 | gsi_next (&gsi); | |
8b11009b ZD |
2216 | } |
2217 | ||
2218 | if (elt) | |
ae50c0cb | 2219 | emit_label ((rtx) *elt); |
242229bb | 2220 | |
caf93cb0 | 2221 | /* Java emits line number notes in the top of labels. |
c22cacf3 | 2222 | ??? Make this go away once line number notes are obsoleted. */ |
242229bb | 2223 | BB_HEAD (bb) = NEXT_INSN (last); |
4b4bf941 | 2224 | if (NOTE_P (BB_HEAD (bb))) |
242229bb | 2225 | BB_HEAD (bb) = NEXT_INSN (BB_HEAD (bb)); |
242229bb | 2226 | note = emit_note_after (NOTE_INSN_BASIC_BLOCK, BB_HEAD (bb)); |
b7211528 | 2227 | |
726a989a | 2228 | maybe_dump_rtl_for_gimple_stmt (stmt, last); |
242229bb JH |
2229 | } |
2230 | else | |
2231 | note = BB_HEAD (bb) = emit_note (NOTE_INSN_BASIC_BLOCK); | |
2232 | ||
2233 | NOTE_BASIC_BLOCK (note) = bb; | |
2234 | ||
726a989a | 2235 | for (; !gsi_end_p (gsi); gsi_next (&gsi)) |
242229bb | 2236 | { |
726a989a | 2237 | gimple stmt = gsi_stmt (gsi); |
cea49550 | 2238 | basic_block new_bb; |
242229bb | 2239 | |
242229bb JH |
2240 | /* Expand this statement, then evaluate the resulting RTL and |
2241 | fixup the CFG accordingly. */ | |
726a989a | 2242 | if (gimple_code (stmt) == GIMPLE_COND) |
cea49550 | 2243 | { |
726a989a | 2244 | new_bb = expand_gimple_cond (bb, stmt); |
cea49550 RH |
2245 | if (new_bb) |
2246 | return new_bb; | |
2247 | } | |
80c7a9eb | 2248 | else |
242229bb | 2249 | { |
726a989a | 2250 | if (is_gimple_call (stmt) && gimple_call_tail_p (stmt)) |
cea49550 RH |
2251 | { |
2252 | bool can_fallthru; | |
2253 | new_bb = expand_gimple_tailcall (bb, stmt, &can_fallthru); | |
2254 | if (new_bb) | |
2255 | { | |
2256 | if (can_fallthru) | |
2257 | bb = new_bb; | |
2258 | else | |
2259 | return new_bb; | |
2260 | } | |
2261 | } | |
4d7a65ea | 2262 | else |
b7211528 | 2263 | { |
4e3825db MM |
2264 | def_operand_p def_p; |
2265 | tree stmt_tree; | |
2266 | def_p = SINGLE_SSA_DEF_OPERAND (stmt, SSA_OP_DEF); | |
2267 | ||
2268 | if (def_p != NULL) | |
2269 | { | |
2270 | /* Ignore this stmt if it is in the list of | |
2271 | replaceable expressions. */ | |
2272 | if (SA.values | |
e97809c6 MM |
2273 | && bitmap_bit_p (SA.values, |
2274 | SSA_NAME_VERSION (DEF_FROM_PTR (def_p)))) | |
4e3825db MM |
2275 | continue; |
2276 | } | |
2277 | stmt_tree = gimple_to_tree (stmt); | |
b7211528 | 2278 | last = get_last_insn (); |
726a989a RB |
2279 | expand_expr_stmt (stmt_tree); |
2280 | maybe_dump_rtl_for_gimple_stmt (stmt, last); | |
2281 | release_stmt_tree (stmt, stmt_tree); | |
b7211528 | 2282 | } |
242229bb JH |
2283 | } |
2284 | } | |
2285 | ||
7241571e | 2286 | /* Expand implicit goto and convert goto_locus. */ |
a9b77cd1 ZD |
2287 | FOR_EACH_EDGE (e, ei, bb->succs) |
2288 | { | |
7241571e JJ |
2289 | if (e->goto_locus && e->goto_block) |
2290 | { | |
2291 | set_curr_insn_source_location (e->goto_locus); | |
2292 | set_curr_insn_block (e->goto_block); | |
2293 | e->goto_locus = curr_insn_locator (); | |
2294 | } | |
2295 | e->goto_block = NULL; | |
2296 | if ((e->flags & EDGE_FALLTHRU) && e->dest != bb->next_bb) | |
2297 | { | |
2298 | emit_jump (label_rtx_for_bb (e->dest)); | |
2299 | e->flags &= ~EDGE_FALLTHRU; | |
2300 | } | |
a9b77cd1 ZD |
2301 | } |
2302 | ||
242229bb JH |
2303 | do_pending_stack_adjust (); |
2304 | ||
3f117656 | 2305 | /* Find the block tail. The last insn in the block is the insn |
242229bb JH |
2306 | before a barrier and/or table jump insn. */ |
2307 | last = get_last_insn (); | |
4b4bf941 | 2308 | if (BARRIER_P (last)) |
242229bb JH |
2309 | last = PREV_INSN (last); |
2310 | if (JUMP_TABLE_DATA_P (last)) | |
2311 | last = PREV_INSN (PREV_INSN (last)); | |
2312 | BB_END (bb) = last; | |
caf93cb0 | 2313 | |
242229bb | 2314 | update_bb_for_insn (bb); |
80c7a9eb | 2315 | |
242229bb JH |
2316 | return bb; |
2317 | } | |
2318 | ||
2319 | ||
2320 | /* Create a basic block for initialization code. */ | |
2321 | ||
2322 | static basic_block | |
2323 | construct_init_block (void) | |
2324 | { | |
2325 | basic_block init_block, first_block; | |
fd44f634 JH |
2326 | edge e = NULL; |
2327 | int flags; | |
275a4187 | 2328 | |
fd44f634 JH |
2329 | /* Multiple entry points not supported yet. */ |
2330 | gcc_assert (EDGE_COUNT (ENTRY_BLOCK_PTR->succs) == 1); | |
5e2d947c JH |
2331 | init_rtl_bb_info (ENTRY_BLOCK_PTR); |
2332 | init_rtl_bb_info (EXIT_BLOCK_PTR); | |
2333 | ENTRY_BLOCK_PTR->flags |= BB_RTL; | |
2334 | EXIT_BLOCK_PTR->flags |= BB_RTL; | |
242229bb | 2335 | |
fd44f634 | 2336 | e = EDGE_SUCC (ENTRY_BLOCK_PTR, 0); |
275a4187 | 2337 | |
fd44f634 JH |
2338 | /* When entry edge points to first basic block, we don't need jump, |
2339 | otherwise we have to jump into proper target. */ | |
2340 | if (e && e->dest != ENTRY_BLOCK_PTR->next_bb) | |
2341 | { | |
726a989a | 2342 | tree label = gimple_block_label (e->dest); |
fd44f634 JH |
2343 | |
2344 | emit_jump (label_rtx (label)); | |
2345 | flags = 0; | |
275a4187 | 2346 | } |
fd44f634 JH |
2347 | else |
2348 | flags = EDGE_FALLTHRU; | |
242229bb JH |
2349 | |
2350 | init_block = create_basic_block (NEXT_INSN (get_insns ()), | |
2351 | get_last_insn (), | |
2352 | ENTRY_BLOCK_PTR); | |
2353 | init_block->frequency = ENTRY_BLOCK_PTR->frequency; | |
2354 | init_block->count = ENTRY_BLOCK_PTR->count; | |
2355 | if (e) | |
2356 | { | |
2357 | first_block = e->dest; | |
2358 | redirect_edge_succ (e, init_block); | |
fd44f634 | 2359 | e = make_edge (init_block, first_block, flags); |
242229bb JH |
2360 | } |
2361 | else | |
2362 | e = make_edge (init_block, EXIT_BLOCK_PTR, EDGE_FALLTHRU); | |
2363 | e->probability = REG_BR_PROB_BASE; | |
2364 | e->count = ENTRY_BLOCK_PTR->count; | |
2365 | ||
2366 | update_bb_for_insn (init_block); | |
2367 | return init_block; | |
2368 | } | |
2369 | ||
55e092c4 JH |
2370 | /* For each lexical block, set BLOCK_NUMBER to the depth at which it is |
2371 | found in the block tree. */ | |
2372 | ||
2373 | static void | |
2374 | set_block_levels (tree block, int level) | |
2375 | { | |
2376 | while (block) | |
2377 | { | |
2378 | BLOCK_NUMBER (block) = level; | |
2379 | set_block_levels (BLOCK_SUBBLOCKS (block), level + 1); | |
2380 | block = BLOCK_CHAIN (block); | |
2381 | } | |
2382 | } | |
242229bb JH |
2383 | |
2384 | /* Create a block containing landing pads and similar stuff. */ | |
2385 | ||
2386 | static void | |
2387 | construct_exit_block (void) | |
2388 | { | |
2389 | rtx head = get_last_insn (); | |
2390 | rtx end; | |
2391 | basic_block exit_block; | |
628f6a4e BE |
2392 | edge e, e2; |
2393 | unsigned ix; | |
2394 | edge_iterator ei; | |
071a42f9 | 2395 | rtx orig_end = BB_END (EXIT_BLOCK_PTR->prev_bb); |
242229bb | 2396 | |
bf08ebeb JH |
2397 | rtl_profile_for_bb (EXIT_BLOCK_PTR); |
2398 | ||
caf93cb0 | 2399 | /* Make sure the locus is set to the end of the function, so that |
242229bb | 2400 | epilogue line numbers and warnings are set properly. */ |
6773e15f | 2401 | if (cfun->function_end_locus != UNKNOWN_LOCATION) |
242229bb JH |
2402 | input_location = cfun->function_end_locus; |
2403 | ||
2404 | /* The following insns belong to the top scope. */ | |
55e092c4 | 2405 | set_curr_insn_block (DECL_INITIAL (current_function_decl)); |
242229bb | 2406 | |
242229bb JH |
2407 | /* Generate rtl for function exit. */ |
2408 | expand_function_end (); | |
2409 | ||
2410 | end = get_last_insn (); | |
2411 | if (head == end) | |
2412 | return; | |
071a42f9 JH |
2413 | /* While emitting the function end we could move end of the last basic block. |
2414 | */ | |
2415 | BB_END (EXIT_BLOCK_PTR->prev_bb) = orig_end; | |
4b4bf941 | 2416 | while (NEXT_INSN (head) && NOTE_P (NEXT_INSN (head))) |
242229bb | 2417 | head = NEXT_INSN (head); |
80c7a9eb RH |
2418 | exit_block = create_basic_block (NEXT_INSN (head), end, |
2419 | EXIT_BLOCK_PTR->prev_bb); | |
242229bb JH |
2420 | exit_block->frequency = EXIT_BLOCK_PTR->frequency; |
2421 | exit_block->count = EXIT_BLOCK_PTR->count; | |
628f6a4e BE |
2422 | |
2423 | ix = 0; | |
2424 | while (ix < EDGE_COUNT (EXIT_BLOCK_PTR->preds)) | |
242229bb | 2425 | { |
8fb790fd | 2426 | e = EDGE_PRED (EXIT_BLOCK_PTR, ix); |
242229bb | 2427 | if (!(e->flags & EDGE_ABNORMAL)) |
628f6a4e BE |
2428 | redirect_edge_succ (e, exit_block); |
2429 | else | |
2430 | ix++; | |
242229bb | 2431 | } |
628f6a4e | 2432 | |
242229bb JH |
2433 | e = make_edge (exit_block, EXIT_BLOCK_PTR, EDGE_FALLTHRU); |
2434 | e->probability = REG_BR_PROB_BASE; | |
2435 | e->count = EXIT_BLOCK_PTR->count; | |
628f6a4e | 2436 | FOR_EACH_EDGE (e2, ei, EXIT_BLOCK_PTR->preds) |
242229bb JH |
2437 | if (e2 != e) |
2438 | { | |
c22cacf3 | 2439 | e->count -= e2->count; |
242229bb JH |
2440 | exit_block->count -= e2->count; |
2441 | exit_block->frequency -= EDGE_FREQUENCY (e2); | |
2442 | } | |
2443 | if (e->count < 0) | |
2444 | e->count = 0; | |
2445 | if (exit_block->count < 0) | |
2446 | exit_block->count = 0; | |
2447 | if (exit_block->frequency < 0) | |
2448 | exit_block->frequency = 0; | |
2449 | update_bb_for_insn (exit_block); | |
2450 | } | |
2451 | ||
c22cacf3 | 2452 | /* Helper function for discover_nonconstant_array_refs. |
a1b23b2f UW |
2453 | Look for ARRAY_REF nodes with non-constant indexes and mark them |
2454 | addressable. */ | |
2455 | ||
2456 | static tree | |
2457 | discover_nonconstant_array_refs_r (tree * tp, int *walk_subtrees, | |
2458 | void *data ATTRIBUTE_UNUSED) | |
2459 | { | |
2460 | tree t = *tp; | |
2461 | ||
2462 | if (IS_TYPE_OR_DECL_P (t)) | |
2463 | *walk_subtrees = 0; | |
2464 | else if (TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF) | |
2465 | { | |
2466 | while (((TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF) | |
2467 | && is_gimple_min_invariant (TREE_OPERAND (t, 1)) | |
2468 | && (!TREE_OPERAND (t, 2) | |
2469 | || is_gimple_min_invariant (TREE_OPERAND (t, 2)))) | |
2470 | || (TREE_CODE (t) == COMPONENT_REF | |
2471 | && (!TREE_OPERAND (t,2) | |
2472 | || is_gimple_min_invariant (TREE_OPERAND (t, 2)))) | |
2473 | || TREE_CODE (t) == BIT_FIELD_REF | |
2474 | || TREE_CODE (t) == REALPART_EXPR | |
2475 | || TREE_CODE (t) == IMAGPART_EXPR | |
2476 | || TREE_CODE (t) == VIEW_CONVERT_EXPR | |
1043771b | 2477 | || CONVERT_EXPR_P (t)) |
a1b23b2f UW |
2478 | t = TREE_OPERAND (t, 0); |
2479 | ||
2480 | if (TREE_CODE (t) == ARRAY_REF || TREE_CODE (t) == ARRAY_RANGE_REF) | |
2481 | { | |
2482 | t = get_base_address (t); | |
6f11d690 RG |
2483 | if (t && DECL_P (t) |
2484 | && DECL_MODE (t) != BLKmode) | |
a1b23b2f UW |
2485 | TREE_ADDRESSABLE (t) = 1; |
2486 | } | |
2487 | ||
2488 | *walk_subtrees = 0; | |
2489 | } | |
2490 | ||
2491 | return NULL_TREE; | |
2492 | } | |
2493 | ||
2494 | /* RTL expansion is not able to compile array references with variable | |
2495 | offsets for arrays stored in single register. Discover such | |
2496 | expressions and mark variables as addressable to avoid this | |
2497 | scenario. */ | |
2498 | ||
2499 | static void | |
2500 | discover_nonconstant_array_refs (void) | |
2501 | { | |
2502 | basic_block bb; | |
726a989a | 2503 | gimple_stmt_iterator gsi; |
a1b23b2f UW |
2504 | |
2505 | FOR_EACH_BB (bb) | |
726a989a RB |
2506 | for (gsi = gsi_start_bb (bb); !gsi_end_p (gsi); gsi_next (&gsi)) |
2507 | { | |
2508 | gimple stmt = gsi_stmt (gsi); | |
2509 | walk_gimple_op (stmt, discover_nonconstant_array_refs_r, NULL); | |
2510 | } | |
a1b23b2f UW |
2511 | } |
2512 | ||
2e3f842f L |
2513 | /* This function sets crtl->args.internal_arg_pointer to a virtual |
2514 | register if DRAP is needed. Local register allocator will replace | |
2515 | virtual_incoming_args_rtx with the virtual register. */ | |
2516 | ||
2517 | static void | |
2518 | expand_stack_alignment (void) | |
2519 | { | |
2520 | rtx drap_rtx; | |
e939805b | 2521 | unsigned int preferred_stack_boundary; |
2e3f842f L |
2522 | |
2523 | if (! SUPPORTS_STACK_ALIGNMENT) | |
2524 | return; | |
2525 | ||
2526 | if (cfun->calls_alloca | |
2527 | || cfun->has_nonlocal_label | |
2528 | || crtl->has_nonlocal_goto) | |
2529 | crtl->need_drap = true; | |
2530 | ||
2531 | gcc_assert (crtl->stack_alignment_needed | |
2532 | <= crtl->stack_alignment_estimated); | |
2533 | ||
2e3f842f L |
2534 | /* Update crtl->stack_alignment_estimated and use it later to align |
2535 | stack. We check PREFERRED_STACK_BOUNDARY if there may be non-call | |
2536 | exceptions since callgraph doesn't collect incoming stack alignment | |
2537 | in this case. */ | |
2538 | if (flag_non_call_exceptions | |
2539 | && PREFERRED_STACK_BOUNDARY > crtl->preferred_stack_boundary) | |
2540 | preferred_stack_boundary = PREFERRED_STACK_BOUNDARY; | |
2541 | else | |
2542 | preferred_stack_boundary = crtl->preferred_stack_boundary; | |
2543 | if (preferred_stack_boundary > crtl->stack_alignment_estimated) | |
2544 | crtl->stack_alignment_estimated = preferred_stack_boundary; | |
2545 | if (preferred_stack_boundary > crtl->stack_alignment_needed) | |
2546 | crtl->stack_alignment_needed = preferred_stack_boundary; | |
2547 | ||
2548 | crtl->stack_realign_needed | |
e939805b | 2549 | = INCOMING_STACK_BOUNDARY < crtl->stack_alignment_estimated; |
d2d93c32 | 2550 | crtl->stack_realign_tried = crtl->stack_realign_needed; |
2e3f842f L |
2551 | |
2552 | crtl->stack_realign_processed = true; | |
2553 | ||
2554 | /* Target has to redefine TARGET_GET_DRAP_RTX to support stack | |
2555 | alignment. */ | |
2556 | gcc_assert (targetm.calls.get_drap_rtx != NULL); | |
2557 | drap_rtx = targetm.calls.get_drap_rtx (); | |
2558 | ||
d015f7cc L |
2559 | /* stack_realign_drap and drap_rtx must match. */ |
2560 | gcc_assert ((stack_realign_drap != 0) == (drap_rtx != NULL)); | |
2561 | ||
2e3f842f L |
2562 | /* Do nothing if NULL is returned, which means DRAP is not needed. */ |
2563 | if (NULL != drap_rtx) | |
2564 | { | |
2565 | crtl->args.internal_arg_pointer = drap_rtx; | |
2566 | ||
2567 | /* Call fixup_tail_calls to clean up REG_EQUIV note if DRAP is | |
2568 | needed. */ | |
2569 | fixup_tail_calls (); | |
2570 | } | |
2571 | } | |
2572 | ||
242229bb JH |
2573 | /* Translate the intermediate representation contained in the CFG |
2574 | from GIMPLE trees to RTL. | |
2575 | ||
2576 | We do conversion per basic block and preserve/update the tree CFG. | |
2577 | This implies we have to do some magic as the CFG can simultaneously | |
2578 | consist of basic blocks containing RTL and GIMPLE trees. This can | |
61ada8ae | 2579 | confuse the CFG hooks, so be careful to not manipulate CFG during |
242229bb JH |
2580 | the expansion. */ |
2581 | ||
c2924966 | 2582 | static unsigned int |
726a989a | 2583 | gimple_expand_cfg (void) |
242229bb JH |
2584 | { |
2585 | basic_block bb, init_block; | |
2586 | sbitmap blocks; | |
0ef90296 ZD |
2587 | edge_iterator ei; |
2588 | edge e; | |
4e3825db MM |
2589 | unsigned i; |
2590 | ||
2591 | rewrite_out_of_ssa (&SA); | |
2592 | SA.partition_to_pseudo = (rtx *)xcalloc (SA.map->num_partitions, | |
2593 | sizeof (rtx)); | |
242229bb | 2594 | |
4586b4ca SB |
2595 | /* Some backends want to know that we are expanding to RTL. */ |
2596 | currently_expanding_to_rtl = 1; | |
2597 | ||
bf08ebeb JH |
2598 | rtl_profile_for_bb (ENTRY_BLOCK_PTR); |
2599 | ||
55e092c4 | 2600 | insn_locators_alloc (); |
fe8a7779 | 2601 | if (!DECL_IS_BUILTIN (current_function_decl)) |
1751ecd6 AH |
2602 | { |
2603 | /* Eventually, all FEs should explicitly set function_start_locus. */ | |
2604 | if (cfun->function_start_locus == UNKNOWN_LOCATION) | |
2605 | set_curr_insn_source_location | |
2606 | (DECL_SOURCE_LOCATION (current_function_decl)); | |
2607 | else | |
2608 | set_curr_insn_source_location (cfun->function_start_locus); | |
2609 | } | |
55e092c4 JH |
2610 | set_curr_insn_block (DECL_INITIAL (current_function_decl)); |
2611 | prologue_locator = curr_insn_locator (); | |
2612 | ||
2613 | /* Make sure first insn is a note even if we don't want linenums. | |
2614 | This makes sure the first insn will never be deleted. | |
2615 | Also, final expects a note to appear there. */ | |
2616 | emit_note (NOTE_INSN_DELETED); | |
6429e3be | 2617 | |
a1b23b2f UW |
2618 | /* Mark arrays indexed with non-constant indices with TREE_ADDRESSABLE. */ |
2619 | discover_nonconstant_array_refs (); | |
2620 | ||
e41b2a33 | 2621 | targetm.expand_to_rtl_hook (); |
cb91fab0 | 2622 | crtl->stack_alignment_needed = STACK_BOUNDARY; |
2e3f842f L |
2623 | crtl->max_used_stack_slot_alignment = STACK_BOUNDARY; |
2624 | crtl->stack_alignment_estimated = STACK_BOUNDARY; | |
cb91fab0 JH |
2625 | crtl->preferred_stack_boundary = STACK_BOUNDARY; |
2626 | cfun->cfg->max_jumptable_ents = 0; | |
2627 | ||
e41b2a33 | 2628 | |
727a31fa | 2629 | /* Expand the variables recorded during gimple lowering. */ |
242229bb JH |
2630 | expand_used_vars (); |
2631 | ||
7d69de61 RH |
2632 | /* Honor stack protection warnings. */ |
2633 | if (warn_stack_protect) | |
2634 | { | |
e3b5732b | 2635 | if (cfun->calls_alloca) |
c5409249 MLI |
2636 | warning (OPT_Wstack_protector, |
2637 | "not protecting local variables: variable length buffer"); | |
cb91fab0 | 2638 | if (has_short_buffer && !crtl->stack_protect_guard) |
c5409249 MLI |
2639 | warning (OPT_Wstack_protector, |
2640 | "not protecting function: no buffer at least %d bytes long", | |
7d69de61 RH |
2641 | (int) PARAM_VALUE (PARAM_SSP_BUFFER_SIZE)); |
2642 | } | |
2643 | ||
242229bb | 2644 | /* Set up parameters and prepare for return, for the function. */ |
b79c5284 | 2645 | expand_function_start (current_function_decl); |
242229bb | 2646 | |
4e3825db MM |
2647 | /* Now that we also have the parameter RTXs, copy them over to our |
2648 | partitions. */ | |
2649 | for (i = 0; i < SA.map->num_partitions; i++) | |
2650 | { | |
2651 | tree var = SSA_NAME_VAR (partition_to_var (SA.map, i)); | |
2652 | ||
2653 | if (TREE_CODE (var) != VAR_DECL | |
2654 | && !SA.partition_to_pseudo[i]) | |
2655 | SA.partition_to_pseudo[i] = DECL_RTL_IF_SET (var); | |
2656 | gcc_assert (SA.partition_to_pseudo[i]); | |
eb7adebc MM |
2657 | |
2658 | /* If this decl was marked as living in multiple places, reset | |
2659 | this now to NULL. */ | |
2660 | if (DECL_RTL_IF_SET (var) == pc_rtx) | |
2661 | SET_DECL_RTL (var, NULL); | |
2662 | ||
4e3825db MM |
2663 | /* Some RTL parts really want to look at DECL_RTL(x) when x |
2664 | was a decl marked in REG_ATTR or MEM_ATTR. We could use | |
2665 | SET_DECL_RTL here making this available, but that would mean | |
2666 | to select one of the potentially many RTLs for one DECL. Instead | |
2667 | of doing that we simply reset the MEM_EXPR of the RTL in question, | |
2668 | then nobody can get at it and hence nobody can call DECL_RTL on it. */ | |
2669 | if (!DECL_RTL_SET_P (var)) | |
2670 | { | |
2671 | if (MEM_P (SA.partition_to_pseudo[i])) | |
2672 | set_mem_expr (SA.partition_to_pseudo[i], NULL); | |
2673 | } | |
2674 | } | |
2675 | ||
242229bb JH |
2676 | /* If this function is `main', emit a call to `__main' |
2677 | to run global initializers, etc. */ | |
2678 | if (DECL_NAME (current_function_decl) | |
2679 | && MAIN_NAME_P (DECL_NAME (current_function_decl)) | |
2680 | && DECL_FILE_SCOPE_P (current_function_decl)) | |
2681 | expand_main_function (); | |
2682 | ||
7d69de61 RH |
2683 | /* Initialize the stack_protect_guard field. This must happen after the |
2684 | call to __main (if any) so that the external decl is initialized. */ | |
cb91fab0 | 2685 | if (crtl->stack_protect_guard) |
7d69de61 RH |
2686 | stack_protect_prologue (); |
2687 | ||
e939805b L |
2688 | /* Update stack boundary if needed. */ |
2689 | if (SUPPORTS_STACK_ALIGNMENT) | |
2690 | { | |
2691 | /* Call update_stack_boundary here to update incoming stack | |
2692 | boundary before TARGET_FUNCTION_OK_FOR_SIBCALL is called. | |
2693 | TARGET_FUNCTION_OK_FOR_SIBCALL needs to know the accurate | |
2694 | incoming stack alignment to check if it is OK to perform | |
2695 | sibcall optimization since sibcall optimization will only | |
2696 | align the outgoing stack to incoming stack boundary. */ | |
2697 | if (targetm.calls.update_stack_boundary) | |
2698 | targetm.calls.update_stack_boundary (); | |
2699 | ||
2700 | /* The incoming stack frame has to be aligned at least at | |
2701 | parm_stack_boundary. */ | |
2702 | gcc_assert (crtl->parm_stack_boundary <= INCOMING_STACK_BOUNDARY); | |
2703 | } | |
2704 | ||
4e3825db MM |
2705 | expand_phi_nodes (&SA); |
2706 | ||
3fbd86b1 | 2707 | /* Register rtl specific functions for cfg. */ |
242229bb JH |
2708 | rtl_register_cfg_hooks (); |
2709 | ||
2710 | init_block = construct_init_block (); | |
2711 | ||
0ef90296 | 2712 | /* Clear EDGE_EXECUTABLE on the entry edge(s). It is cleaned from the |
4e3825db | 2713 | remaining edges later. */ |
0ef90296 ZD |
2714 | FOR_EACH_EDGE (e, ei, ENTRY_BLOCK_PTR->succs) |
2715 | e->flags &= ~EDGE_EXECUTABLE; | |
2716 | ||
8b11009b | 2717 | lab_rtx_for_bb = pointer_map_create (); |
242229bb | 2718 | FOR_BB_BETWEEN (bb, init_block->next_bb, EXIT_BLOCK_PTR, next_bb) |
10d22567 | 2719 | bb = expand_gimple_basic_block (bb); |
bf08ebeb | 2720 | |
4e3825db MM |
2721 | execute_free_datastructures (); |
2722 | finish_out_of_ssa (&SA); | |
2723 | ||
bf08ebeb JH |
2724 | /* Expansion is used by optimization passes too, set maybe_hot_insn_p |
2725 | conservatively to true until they are all profile aware. */ | |
8b11009b | 2726 | pointer_map_destroy (lab_rtx_for_bb); |
cb91fab0 | 2727 | free_histograms (); |
242229bb JH |
2728 | |
2729 | construct_exit_block (); | |
55e092c4 JH |
2730 | set_curr_insn_block (DECL_INITIAL (current_function_decl)); |
2731 | insn_locators_finalize (); | |
242229bb | 2732 | |
e8a2a782 | 2733 | /* Convert tree EH labels to RTL EH labels and zap the tree EH table. */ |
242229bb | 2734 | convert_from_eh_region_ranges (); |
e8a2a782 | 2735 | set_eh_throw_stmt_table (cfun, NULL); |
242229bb JH |
2736 | |
2737 | rebuild_jump_labels (get_insns ()); | |
2738 | find_exception_handler_labels (); | |
2739 | ||
4e3825db MM |
2740 | FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR, EXIT_BLOCK_PTR, next_bb) |
2741 | { | |
2742 | edge e; | |
2743 | edge_iterator ei; | |
2744 | for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); ) | |
2745 | { | |
2746 | if (e->insns.r) | |
2747 | commit_one_edge_insertion (e); | |
2748 | else | |
2749 | ei_next (&ei); | |
2750 | } | |
2751 | } | |
2752 | ||
2753 | /* We're done expanding trees to RTL. */ | |
2754 | currently_expanding_to_rtl = 0; | |
2755 | ||
2756 | FOR_BB_BETWEEN (bb, ENTRY_BLOCK_PTR->next_bb, EXIT_BLOCK_PTR, next_bb) | |
2757 | { | |
2758 | edge e; | |
2759 | edge_iterator ei; | |
2760 | for (ei = ei_start (bb->succs); (e = ei_safe_edge (ei)); ) | |
2761 | { | |
2762 | /* Clear EDGE_EXECUTABLE. This flag is never used in the backend. */ | |
2763 | e->flags &= ~EDGE_EXECUTABLE; | |
2764 | ||
2765 | /* At the moment not all abnormal edges match the RTL | |
2766 | representation. It is safe to remove them here as | |
2767 | find_many_sub_basic_blocks will rediscover them. | |
2768 | In the future we should get this fixed properly. */ | |
2769 | if ((e->flags & EDGE_ABNORMAL) | |
2770 | && !(e->flags & EDGE_SIBCALL)) | |
2771 | remove_edge (e); | |
2772 | else | |
2773 | ei_next (&ei); | |
2774 | } | |
2775 | } | |
2776 | ||
242229bb JH |
2777 | blocks = sbitmap_alloc (last_basic_block); |
2778 | sbitmap_ones (blocks); | |
2779 | find_many_sub_basic_blocks (blocks); | |
242229bb | 2780 | sbitmap_free (blocks); |
4e3825db | 2781 | purge_all_dead_edges (); |
242229bb JH |
2782 | |
2783 | compact_blocks (); | |
2e3f842f L |
2784 | |
2785 | expand_stack_alignment (); | |
2786 | ||
242229bb | 2787 | #ifdef ENABLE_CHECKING |
62e5bf5d | 2788 | verify_flow_info (); |
242229bb | 2789 | #endif |
9f8628ba PB |
2790 | |
2791 | /* There's no need to defer outputting this function any more; we | |
2792 | know we want to output it. */ | |
2793 | DECL_DEFER_OUTPUT (current_function_decl) = 0; | |
2794 | ||
2795 | /* Now that we're done expanding trees to RTL, we shouldn't have any | |
2796 | more CONCATs anywhere. */ | |
2797 | generating_concat_p = 0; | |
2798 | ||
b7211528 SB |
2799 | if (dump_file) |
2800 | { | |
2801 | fprintf (dump_file, | |
2802 | "\n\n;;\n;; Full RTL generated for this function:\n;;\n"); | |
2803 | /* And the pass manager will dump RTL for us. */ | |
2804 | } | |
ef330312 PB |
2805 | |
2806 | /* If we're emitting a nested function, make sure its parent gets | |
2807 | emitted as well. Doing otherwise confuses debug info. */ | |
c22cacf3 | 2808 | { |
ef330312 PB |
2809 | tree parent; |
2810 | for (parent = DECL_CONTEXT (current_function_decl); | |
c22cacf3 MS |
2811 | parent != NULL_TREE; |
2812 | parent = get_containing_scope (parent)) | |
ef330312 | 2813 | if (TREE_CODE (parent) == FUNCTION_DECL) |
c22cacf3 | 2814 | TREE_SYMBOL_REFERENCED (DECL_ASSEMBLER_NAME (parent)) = 1; |
ef330312 | 2815 | } |
c22cacf3 | 2816 | |
ef330312 PB |
2817 | /* We are now committed to emitting code for this function. Do any |
2818 | preparation, such as emitting abstract debug info for the inline | |
2819 | before it gets mangled by optimization. */ | |
2820 | if (cgraph_function_possibly_inlined_p (current_function_decl)) | |
2821 | (*debug_hooks->outlining_inline_function) (current_function_decl); | |
2822 | ||
2823 | TREE_ASM_WRITTEN (current_function_decl) = 1; | |
4bb1e037 AP |
2824 | |
2825 | /* After expanding, the return labels are no longer needed. */ | |
2826 | return_label = NULL; | |
2827 | naked_return_label = NULL; | |
55e092c4 JH |
2828 | /* Tag the blocks with a depth number so that change_scope can find |
2829 | the common parent easily. */ | |
2830 | set_block_levels (DECL_INITIAL (cfun->decl), 0); | |
bf08ebeb | 2831 | default_rtl_profile (); |
c2924966 | 2832 | return 0; |
242229bb JH |
2833 | } |
2834 | ||
e3b5732b | 2835 | struct rtl_opt_pass pass_expand = |
242229bb | 2836 | { |
8ddbbcae | 2837 | { |
e3b5732b | 2838 | RTL_PASS, |
c22cacf3 | 2839 | "expand", /* name */ |
242229bb | 2840 | NULL, /* gate */ |
726a989a | 2841 | gimple_expand_cfg, /* execute */ |
242229bb JH |
2842 | NULL, /* sub */ |
2843 | NULL, /* next */ | |
2844 | 0, /* static_pass_number */ | |
c22cacf3 | 2845 | TV_EXPAND, /* tv_id */ |
4e3825db | 2846 | PROP_ssa | PROP_gimple_leh | PROP_cfg,/* properties_required */ |
242229bb | 2847 | PROP_rtl, /* properties_provided */ |
4e3825db MM |
2848 | PROP_ssa | PROP_trees, /* properties_destroyed */ |
2849 | TODO_verify_ssa | TODO_verify_flow | |
2850 | | TODO_verify_stmts, /* todo_flags_start */ | |
2851 | TODO_dump_func | |
2852 | | TODO_ggc_collect /* todo_flags_finish */ | |
8ddbbcae | 2853 | } |
242229bb | 2854 | }; |