Mercurial > hg > CbC > CbC_gcc
annotate gcc/tree-stdarg.c @ 63:b7f97abdc517 gcc-4.6-20100522
update gcc from gcc-4.5.0 to gcc-4.6
| author | ryoma <e075725@ie.u-ryukyu.ac.jp> |
|---|---|
| date | Mon, 24 May 2010 12:47:05 +0900 |
| parents | 77e2b8dfacca |
| children | f6334be47118 |
| rev | line source |
|---|---|
| 0 | 1 /* Pass computing data for optimizing stdarg functions. |
|
63
b7f97abdc517
update gcc from gcc-4.5.0 to gcc-4.6
ryoma <e075725@ie.u-ryukyu.ac.jp>
parents:
55
diff
changeset
|
2 Copyright (C) 2004, 2005, 2007, 2008, 2009, 2010 |
|
b7f97abdc517
update gcc from gcc-4.5.0 to gcc-4.6
ryoma <e075725@ie.u-ryukyu.ac.jp>
parents:
55
diff
changeset
|
3 Free Software Foundation, Inc. |
| 0 | 4 Contributed by Jakub Jelinek <jakub@redhat.com> |
| 5 | |
| 6 This file is part of GCC. | |
| 7 | |
| 8 GCC is free software; you can redistribute it and/or modify | |
| 9 it under the terms of the GNU General Public License as published by | |
| 10 the Free Software Foundation; either version 3, or (at your option) | |
| 11 any later version. | |
| 12 | |
| 13 GCC is distributed in the hope that it will be useful, | |
| 14 but WITHOUT ANY WARRANTY; without even the implied warranty of | |
| 15 MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the | |
| 16 GNU General Public License for more details. | |
| 17 | |
| 18 You should have received a copy of the GNU General Public License | |
| 19 along with GCC; see the file COPYING3. If not see | |
| 20 <http://www.gnu.org/licenses/>. */ | |
| 21 | |
| 22 #include "config.h" | |
| 23 #include "system.h" | |
| 24 #include "coretypes.h" | |
| 25 #include "tm.h" | |
| 26 #include "tree.h" | |
| 27 #include "function.h" | |
| 28 #include "langhooks.h" | |
| 29 #include "diagnostic.h" | |
|
63
b7f97abdc517
update gcc from gcc-4.5.0 to gcc-4.6
ryoma <e075725@ie.u-ryukyu.ac.jp>
parents:
55
diff
changeset
|
30 #include "gimple-pretty-print.h" |
| 0 | 31 #include "target.h" |
| 32 #include "tree-flow.h" | |
| 33 #include "tree-pass.h" | |
| 34 #include "tree-stdarg.h" | |
| 35 | |
| 36 /* A simple pass that attempts to optimize stdarg functions on architectures | |
| 37 that need to save register arguments to stack on entry to stdarg functions. | |
| 38 If the function doesn't use any va_start macros, no registers need to | |
| 39 be saved. If va_start macros are used, the va_list variables don't escape | |
| 40 the function, it is only necessary to save registers that will be used | |
| 41 in va_arg macros. E.g. if va_arg is only used with integral types | |
| 42 in the function, floating point registers don't need to be saved, etc. */ | |
| 43 | |
| 44 | |
| 45 /* Return true if basic block VA_ARG_BB is dominated by VA_START_BB and | |
| 46 is executed at most as many times as VA_START_BB. */ | |
| 47 | |
| 48 static bool | |
| 49 reachable_at_most_once (basic_block va_arg_bb, basic_block va_start_bb) | |
| 50 { | |
| 51 VEC (edge, heap) *stack = NULL; | |
| 52 edge e; | |
| 53 edge_iterator ei; | |
| 54 sbitmap visited; | |
| 55 bool ret; | |
| 56 | |
| 57 if (va_arg_bb == va_start_bb) | |
| 58 return true; | |
| 59 | |
| 60 if (! dominated_by_p (CDI_DOMINATORS, va_arg_bb, va_start_bb)) | |
| 61 return false; | |
| 62 | |
| 63 visited = sbitmap_alloc (last_basic_block); | |
| 64 sbitmap_zero (visited); | |
| 65 ret = true; | |
| 66 | |
| 67 FOR_EACH_EDGE (e, ei, va_arg_bb->preds) | |
| 68 VEC_safe_push (edge, heap, stack, e); | |
| 69 | |
| 70 while (! VEC_empty (edge, stack)) | |
| 71 { | |
| 72 basic_block src; | |
| 73 | |
| 74 e = VEC_pop (edge, stack); | |
| 75 src = e->src; | |
| 76 | |
| 77 if (e->flags & EDGE_COMPLEX) | |
| 78 { | |
| 79 ret = false; | |
| 80 break; | |
| 81 } | |
| 82 | |
| 83 if (src == va_start_bb) | |
| 84 continue; | |
| 85 | |
| 86 /* va_arg_bb can be executed more times than va_start_bb. */ | |
| 87 if (src == va_arg_bb) | |
| 88 { | |
| 89 ret = false; | |
| 90 break; | |
| 91 } | |
| 92 | |
| 93 gcc_assert (src != ENTRY_BLOCK_PTR); | |
| 94 | |
| 95 if (! TEST_BIT (visited, src->index)) | |
| 96 { | |
| 97 SET_BIT (visited, src->index); | |
| 98 FOR_EACH_EDGE (e, ei, src->preds) | |
| 99 VEC_safe_push (edge, heap, stack, e); | |
| 100 } | |
| 101 } | |
| 102 | |
| 103 VEC_free (edge, heap, stack); | |
| 104 sbitmap_free (visited); | |
| 105 return ret; | |
| 106 } | |
| 107 | |
| 108 | |
| 109 /* For statement COUNTER = RHS, if RHS is COUNTER + constant, | |
| 110 return constant, otherwise return (unsigned HOST_WIDE_INT) -1. | |
| 111 GPR_P is true if this is GPR counter. */ | |
| 112 | |
| 113 static unsigned HOST_WIDE_INT | |
| 114 va_list_counter_bump (struct stdarg_info *si, tree counter, tree rhs, | |
| 115 bool gpr_p) | |
| 116 { | |
| 117 tree lhs, orig_lhs; | |
| 118 gimple stmt; | |
| 119 unsigned HOST_WIDE_INT ret = 0, val, counter_val; | |
| 120 unsigned int max_size; | |
| 121 | |
| 122 if (si->offsets == NULL) | |
| 123 { | |
| 124 unsigned int i; | |
| 125 | |
| 126 si->offsets = XNEWVEC (int, num_ssa_names); | |
| 127 for (i = 0; i < num_ssa_names; ++i) | |
| 128 si->offsets[i] = -1; | |
| 129 } | |
| 130 | |
| 131 counter_val = gpr_p ? cfun->va_list_gpr_size : cfun->va_list_fpr_size; | |
| 132 max_size = gpr_p ? VA_LIST_MAX_GPR_SIZE : VA_LIST_MAX_FPR_SIZE; | |
| 133 orig_lhs = lhs = rhs; | |
| 134 while (lhs) | |
| 135 { | |
| 136 enum tree_code rhs_code; | |
| 137 | |
| 138 if (si->offsets[SSA_NAME_VERSION (lhs)] != -1) | |
| 139 { | |
| 140 if (counter_val >= max_size) | |
| 141 { | |
| 142 ret = max_size; | |
| 143 break; | |
| 144 } | |
| 145 | |
| 146 ret -= counter_val - si->offsets[SSA_NAME_VERSION (lhs)]; | |
| 147 break; | |
| 148 } | |
| 149 | |
| 150 stmt = SSA_NAME_DEF_STMT (lhs); | |
| 151 | |
| 152 if (!is_gimple_assign (stmt) || gimple_assign_lhs (stmt) != lhs) | |
| 153 return (unsigned HOST_WIDE_INT) -1; | |
| 154 | |
| 155 rhs_code = gimple_assign_rhs_code (stmt); | |
| 156 if ((get_gimple_rhs_class (rhs_code) == GIMPLE_SINGLE_RHS | |
| 157 || gimple_assign_cast_p (stmt)) | |
| 158 && TREE_CODE (gimple_assign_rhs1 (stmt)) == SSA_NAME) | |
| 159 { | |
| 160 lhs = gimple_assign_rhs1 (stmt); | |
| 161 continue; | |
| 162 } | |
| 163 | |
| 164 if ((rhs_code == POINTER_PLUS_EXPR | |
| 165 || rhs_code == PLUS_EXPR) | |
| 166 && TREE_CODE (gimple_assign_rhs1 (stmt)) == SSA_NAME | |
| 167 && host_integerp (gimple_assign_rhs2 (stmt), 1)) | |
| 168 { | |
| 169 ret += tree_low_cst (gimple_assign_rhs2 (stmt), 1); | |
| 170 lhs = gimple_assign_rhs1 (stmt); | |
| 171 continue; | |
| 172 } | |
| 173 | |
| 174 if (get_gimple_rhs_class (rhs_code) != GIMPLE_SINGLE_RHS) | |
| 175 return (unsigned HOST_WIDE_INT) -1; | |
| 176 | |
| 177 rhs = gimple_assign_rhs1 (stmt); | |
| 178 if (TREE_CODE (counter) != TREE_CODE (rhs)) | |
| 179 return (unsigned HOST_WIDE_INT) -1; | |
| 180 | |
| 181 if (TREE_CODE (counter) == COMPONENT_REF) | |
| 182 { | |
| 183 if (get_base_address (counter) != get_base_address (rhs) | |
| 184 || TREE_CODE (TREE_OPERAND (rhs, 1)) != FIELD_DECL | |
| 185 || TREE_OPERAND (counter, 1) != TREE_OPERAND (rhs, 1)) | |
| 186 return (unsigned HOST_WIDE_INT) -1; | |
| 187 } | |
| 188 else if (counter != rhs) | |
| 189 return (unsigned HOST_WIDE_INT) -1; | |
| 190 | |
| 191 lhs = NULL; | |
| 192 } | |
| 193 | |
| 194 lhs = orig_lhs; | |
| 195 val = ret + counter_val; | |
| 196 while (lhs) | |
| 197 { | |
| 198 enum tree_code rhs_code; | |
| 199 | |
| 200 if (si->offsets[SSA_NAME_VERSION (lhs)] != -1) | |
| 201 break; | |
| 202 | |
| 203 if (val >= max_size) | |
| 204 si->offsets[SSA_NAME_VERSION (lhs)] = max_size; | |
| 205 else | |
| 206 si->offsets[SSA_NAME_VERSION (lhs)] = val; | |
| 207 | |
| 208 stmt = SSA_NAME_DEF_STMT (lhs); | |
| 209 | |
| 210 rhs_code = gimple_assign_rhs_code (stmt); | |
| 211 if ((get_gimple_rhs_class (rhs_code) == GIMPLE_SINGLE_RHS | |
| 212 || gimple_assign_cast_p (stmt)) | |
| 213 && TREE_CODE (gimple_assign_rhs1 (stmt)) == SSA_NAME) | |
| 214 { | |
| 215 lhs = gimple_assign_rhs1 (stmt); | |
| 216 continue; | |
| 217 } | |
| 218 | |
| 219 if ((rhs_code == POINTER_PLUS_EXPR | |
| 220 || rhs_code == PLUS_EXPR) | |
| 221 && TREE_CODE (gimple_assign_rhs1 (stmt)) == SSA_NAME | |
| 222 && host_integerp (gimple_assign_rhs2 (stmt), 1)) | |
| 223 { | |
| 224 val -= tree_low_cst (gimple_assign_rhs2 (stmt), 1); | |
| 225 lhs = gimple_assign_rhs1 (stmt); | |
| 226 continue; | |
| 227 } | |
| 228 | |
| 229 lhs = NULL; | |
| 230 } | |
| 231 | |
| 232 return ret; | |
| 233 } | |
| 234 | |
| 235 | |
| 236 /* Called by walk_tree to look for references to va_list variables. */ | |
| 237 | |
| 238 static tree | |
| 239 find_va_list_reference (tree *tp, int *walk_subtrees ATTRIBUTE_UNUSED, | |
| 240 void *data) | |
| 241 { | |
| 242 bitmap va_list_vars = (bitmap) ((struct walk_stmt_info *) data)->info; | |
| 243 tree var = *tp; | |
| 244 | |
| 245 if (TREE_CODE (var) == SSA_NAME) | |
| 246 var = SSA_NAME_VAR (var); | |
| 247 | |
| 248 if (TREE_CODE (var) == VAR_DECL | |
| 249 && bitmap_bit_p (va_list_vars, DECL_UID (var))) | |
| 250 return var; | |
| 251 | |
| 252 return NULL_TREE; | |
| 253 } | |
| 254 | |
| 255 | |
| 256 /* Helper function of va_list_counter_struct_op. Compute | |
| 257 cfun->va_list_{g,f}pr_size. AP is a va_list GPR/FPR counter, | |
| 258 if WRITE_P is true, seen in AP = VAR, otherwise seen in VAR = AP | |
| 259 statement. GPR_P is true if AP is a GPR counter, false if it is | |
| 260 a FPR counter. */ | |
| 261 | |
| 262 static void | |
| 263 va_list_counter_op (struct stdarg_info *si, tree ap, tree var, bool gpr_p, | |
| 264 bool write_p) | |
| 265 { | |
| 266 unsigned HOST_WIDE_INT increment; | |
| 267 | |
| 268 if (si->compute_sizes < 0) | |
| 269 { | |
| 270 si->compute_sizes = 0; | |
| 271 if (si->va_start_count == 1 | |
| 272 && reachable_at_most_once (si->bb, si->va_start_bb)) | |
| 273 si->compute_sizes = 1; | |
| 274 | |
| 275 if (dump_file && (dump_flags & TDF_DETAILS)) | |
| 276 fprintf (dump_file, | |
| 277 "bb%d will %sbe executed at most once for each va_start " | |
| 278 "in bb%d\n", si->bb->index, si->compute_sizes ? "" : "not ", | |
| 279 si->va_start_bb->index); | |
| 280 } | |
| 281 | |
| 282 if (write_p | |
| 283 && si->compute_sizes | |
| 284 && (increment = va_list_counter_bump (si, ap, var, gpr_p)) + 1 > 1) | |
| 285 { | |
| 286 if (gpr_p && cfun->va_list_gpr_size + increment < VA_LIST_MAX_GPR_SIZE) | |
| 287 { | |
| 288 cfun->va_list_gpr_size += increment; | |
| 289 return; | |
| 290 } | |
| 291 | |
| 292 if (!gpr_p && cfun->va_list_fpr_size + increment < VA_LIST_MAX_FPR_SIZE) | |
| 293 { | |
| 294 cfun->va_list_fpr_size += increment; | |
| 295 return; | |
| 296 } | |
| 297 } | |
| 298 | |
| 299 if (write_p || !si->compute_sizes) | |
| 300 { | |
| 301 if (gpr_p) | |
| 302 cfun->va_list_gpr_size = VA_LIST_MAX_GPR_SIZE; | |
| 303 else | |
| 304 cfun->va_list_fpr_size = VA_LIST_MAX_FPR_SIZE; | |
| 305 } | |
| 306 } | |
| 307 | |
| 308 | |
| 309 /* If AP is a va_list GPR/FPR counter, compute cfun->va_list_{g,f}pr_size. | |
| 310 If WRITE_P is true, AP has been seen in AP = VAR assignment, if WRITE_P | |
| 311 is false, AP has been seen in VAR = AP assignment. | |
| 312 Return true if the AP = VAR (resp. VAR = AP) statement is a recognized | |
| 313 va_arg operation that doesn't cause the va_list variable to escape | |
| 314 current function. */ | |
| 315 | |
| 316 static bool | |
| 317 va_list_counter_struct_op (struct stdarg_info *si, tree ap, tree var, | |
| 318 bool write_p) | |
| 319 { | |
| 320 tree base; | |
| 321 | |
| 322 if (TREE_CODE (ap) != COMPONENT_REF | |
| 323 || TREE_CODE (TREE_OPERAND (ap, 1)) != FIELD_DECL) | |
| 324 return false; | |
| 325 | |
| 326 if (TREE_CODE (var) != SSA_NAME | |
| 327 || bitmap_bit_p (si->va_list_vars, DECL_UID (SSA_NAME_VAR (var)))) | |
| 328 return false; | |
| 329 | |
| 330 base = get_base_address (ap); | |
| 331 if (TREE_CODE (base) != VAR_DECL | |
| 332 || !bitmap_bit_p (si->va_list_vars, DECL_UID (base))) | |
| 333 return false; | |
| 334 | |
| 335 if (TREE_OPERAND (ap, 1) == va_list_gpr_counter_field) | |
| 336 va_list_counter_op (si, ap, var, true, write_p); | |
| 337 else if (TREE_OPERAND (ap, 1) == va_list_fpr_counter_field) | |
| 338 va_list_counter_op (si, ap, var, false, write_p); | |
| 339 | |
| 340 return true; | |
| 341 } | |
| 342 | |
| 343 | |
| 344 /* Check for TEM = AP. Return true if found and the caller shouldn't | |
| 345 search for va_list references in the statement. */ | |
| 346 | |
| 347 static bool | |
| 348 va_list_ptr_read (struct stdarg_info *si, tree ap, tree tem) | |
| 349 { | |
| 350 if (TREE_CODE (ap) != VAR_DECL | |
| 351 || !bitmap_bit_p (si->va_list_vars, DECL_UID (ap))) | |
| 352 return false; | |
| 353 | |
| 354 if (TREE_CODE (tem) != SSA_NAME | |
| 355 || bitmap_bit_p (si->va_list_vars, | |
| 356 DECL_UID (SSA_NAME_VAR (tem))) | |
| 357 || is_global_var (SSA_NAME_VAR (tem))) | |
| 358 return false; | |
| 359 | |
| 360 if (si->compute_sizes < 0) | |
| 361 { | |
| 362 si->compute_sizes = 0; | |
| 363 if (si->va_start_count == 1 | |
| 364 && reachable_at_most_once (si->bb, si->va_start_bb)) | |
| 365 si->compute_sizes = 1; | |
| 366 | |
| 367 if (dump_file && (dump_flags & TDF_DETAILS)) | |
| 368 fprintf (dump_file, | |
| 369 "bb%d will %sbe executed at most once for each va_start " | |
| 370 "in bb%d\n", si->bb->index, si->compute_sizes ? "" : "not ", | |
| 371 si->va_start_bb->index); | |
| 372 } | |
| 373 | |
| 374 /* For void * or char * va_list types, there is just one counter. | |
| 375 If va_arg is used in a loop, we don't know how many registers need | |
| 376 saving. */ | |
| 377 if (! si->compute_sizes) | |
| 378 return false; | |
| 379 | |
| 380 if (va_list_counter_bump (si, ap, tem, true) == (unsigned HOST_WIDE_INT) -1) | |
| 381 return false; | |
| 382 | |
| 383 /* Note the temporary, as we need to track whether it doesn't escape | |
| 384 the current function. */ | |
| 385 bitmap_set_bit (si->va_list_escape_vars, | |
| 386 DECL_UID (SSA_NAME_VAR (tem))); | |
| 387 return true; | |
| 388 } | |
| 389 | |
| 390 | |
| 391 /* Check for: | |
| 392 tem1 = AP; | |
| 393 TEM2 = tem1 + CST; | |
| 394 AP = TEM2; | |
| 395 sequence and update cfun->va_list_gpr_size. Return true if found. */ | |
| 396 | |
| 397 static bool | |
| 398 va_list_ptr_write (struct stdarg_info *si, tree ap, tree tem2) | |
| 399 { | |
| 400 unsigned HOST_WIDE_INT increment; | |
| 401 | |
| 402 if (TREE_CODE (ap) != VAR_DECL | |
| 403 || !bitmap_bit_p (si->va_list_vars, DECL_UID (ap))) | |
| 404 return false; | |
| 405 | |
| 406 if (TREE_CODE (tem2) != SSA_NAME | |
| 407 || bitmap_bit_p (si->va_list_vars, DECL_UID (SSA_NAME_VAR (tem2)))) | |
| 408 return false; | |
| 409 | |
| 410 if (si->compute_sizes <= 0) | |
| 411 return false; | |
| 412 | |
| 413 increment = va_list_counter_bump (si, ap, tem2, true); | |
| 414 if (increment + 1 <= 1) | |
| 415 return false; | |
| 416 | |
| 417 if (cfun->va_list_gpr_size + increment < VA_LIST_MAX_GPR_SIZE) | |
| 418 cfun->va_list_gpr_size += increment; | |
| 419 else | |
| 420 cfun->va_list_gpr_size = VA_LIST_MAX_GPR_SIZE; | |
| 421 | |
| 422 return true; | |
| 423 } | |
| 424 | |
| 425 | |
| 426 /* If RHS is X, (some type *) X or X + CST for X a temporary variable | |
| 427 containing value of some va_list variable plus optionally some constant, | |
| 428 either set si->va_list_escapes or add LHS to si->va_list_escape_vars, | |
| 429 depending whether LHS is a function local temporary. */ | |
| 430 | |
| 431 static void | |
| 432 check_va_list_escapes (struct stdarg_info *si, tree lhs, tree rhs) | |
| 433 { | |
| 434 if (! POINTER_TYPE_P (TREE_TYPE (rhs))) | |
| 435 return; | |
| 436 | |
| 437 if (TREE_CODE (rhs) != SSA_NAME | |
| 438 || ! bitmap_bit_p (si->va_list_escape_vars, | |
| 439 DECL_UID (SSA_NAME_VAR (rhs)))) | |
| 440 return; | |
| 441 | |
| 442 if (TREE_CODE (lhs) != SSA_NAME || is_global_var (SSA_NAME_VAR (lhs))) | |
| 443 { | |
| 444 si->va_list_escapes = true; | |
| 445 return; | |
| 446 } | |
| 447 | |
| 448 if (si->compute_sizes < 0) | |
| 449 { | |
| 450 si->compute_sizes = 0; | |
| 451 if (si->va_start_count == 1 | |
| 452 && reachable_at_most_once (si->bb, si->va_start_bb)) | |
| 453 si->compute_sizes = 1; | |
| 454 | |
| 455 if (dump_file && (dump_flags & TDF_DETAILS)) | |
| 456 fprintf (dump_file, | |
| 457 "bb%d will %sbe executed at most once for each va_start " | |
| 458 "in bb%d\n", si->bb->index, si->compute_sizes ? "" : "not ", | |
| 459 si->va_start_bb->index); | |
| 460 } | |
| 461 | |
| 462 /* For void * or char * va_list types, there is just one counter. | |
| 463 If va_arg is used in a loop, we don't know how many registers need | |
| 464 saving. */ | |
| 465 if (! si->compute_sizes) | |
| 466 { | |
| 467 si->va_list_escapes = true; | |
| 468 return; | |
| 469 } | |
| 470 | |
| 471 if (va_list_counter_bump (si, si->va_start_ap, lhs, true) | |
| 472 == (unsigned HOST_WIDE_INT) -1) | |
| 473 { | |
| 474 si->va_list_escapes = true; | |
| 475 return; | |
| 476 } | |
| 477 | |
| 478 bitmap_set_bit (si->va_list_escape_vars, | |
| 479 DECL_UID (SSA_NAME_VAR (lhs))); | |
| 480 } | |
| 481 | |
| 482 | |
| 483 /* Check all uses of temporaries from si->va_list_escape_vars bitmap. | |
| 484 Return true if va_list might be escaping. */ | |
| 485 | |
| 486 static bool | |
| 487 check_all_va_list_escapes (struct stdarg_info *si) | |
| 488 { | |
| 489 basic_block bb; | |
| 490 | |
| 491 FOR_EACH_BB (bb) | |
| 492 { | |
| 493 gimple_stmt_iterator i; | |
| 494 | |
| 495 for (i = gsi_start_bb (bb); !gsi_end_p (i); gsi_next (&i)) | |
| 496 { | |
| 497 gimple stmt = gsi_stmt (i); | |
| 498 tree use; | |
| 499 ssa_op_iter iter; | |
| 500 | |
|
55
77e2b8dfacca
update it from 4.4.3 to 4.5.0
ryoma <e075725@ie.u-ryukyu.ac.jp>
parents:
0
diff
changeset
|
501 if (is_gimple_debug (stmt)) |
|
77e2b8dfacca
update it from 4.4.3 to 4.5.0
ryoma <e075725@ie.u-ryukyu.ac.jp>
parents:
0
diff
changeset
|
502 continue; |
|
77e2b8dfacca
update it from 4.4.3 to 4.5.0
ryoma <e075725@ie.u-ryukyu.ac.jp>
parents:
0
diff
changeset
|
503 |
| 0 | 504 FOR_EACH_SSA_TREE_OPERAND (use, stmt, iter, SSA_OP_ALL_USES) |
| 505 { | |
| 506 if (! bitmap_bit_p (si->va_list_escape_vars, | |
| 507 DECL_UID (SSA_NAME_VAR (use)))) | |
| 508 continue; | |
| 509 | |
| 510 if (is_gimple_assign (stmt)) | |
| 511 { | |
| 512 tree rhs = gimple_assign_rhs1 (stmt); | |
| 513 enum tree_code rhs_code = gimple_assign_rhs_code (stmt); | |
| 514 | |
| 515 /* x = *ap_temp; */ | |
| 516 if (gimple_assign_rhs_code (stmt) == INDIRECT_REF | |
| 517 && TREE_OPERAND (rhs, 0) == use | |
| 518 && TYPE_SIZE_UNIT (TREE_TYPE (rhs)) | |
| 519 && host_integerp (TYPE_SIZE_UNIT (TREE_TYPE (rhs)), 1) | |
| 520 && si->offsets[SSA_NAME_VERSION (use)] != -1) | |
| 521 { | |
| 522 unsigned HOST_WIDE_INT gpr_size; | |
| 523 tree access_size = TYPE_SIZE_UNIT (TREE_TYPE (rhs)); | |
| 524 | |
| 525 gpr_size = si->offsets[SSA_NAME_VERSION (use)] | |
| 526 + tree_low_cst (access_size, 1); | |
| 527 if (gpr_size >= VA_LIST_MAX_GPR_SIZE) | |
| 528 cfun->va_list_gpr_size = VA_LIST_MAX_GPR_SIZE; | |
| 529 else if (gpr_size > cfun->va_list_gpr_size) | |
| 530 cfun->va_list_gpr_size = gpr_size; | |
| 531 continue; | |
| 532 } | |
| 533 | |
| 534 /* va_arg sequences may contain | |
| 535 other_ap_temp = ap_temp; | |
| 536 other_ap_temp = ap_temp + constant; | |
| 537 other_ap_temp = (some_type *) ap_temp; | |
| 538 ap = ap_temp; | |
| 539 statements. */ | |
| 540 if (rhs == use | |
| 541 && ((rhs_code == POINTER_PLUS_EXPR | |
| 542 && (TREE_CODE (gimple_assign_rhs2 (stmt)) | |
| 543 == INTEGER_CST)) | |
| 544 || gimple_assign_cast_p (stmt) | |
| 545 || (get_gimple_rhs_class (rhs_code) | |
| 546 == GIMPLE_SINGLE_RHS))) | |
| 547 { | |
| 548 tree lhs = gimple_assign_lhs (stmt); | |
| 549 | |
| 550 if (TREE_CODE (lhs) == SSA_NAME | |
| 551 && bitmap_bit_p (si->va_list_escape_vars, | |
| 552 DECL_UID (SSA_NAME_VAR (lhs)))) | |
| 553 continue; | |
| 554 | |
| 555 if (TREE_CODE (lhs) == VAR_DECL | |
| 556 && bitmap_bit_p (si->va_list_vars, | |
| 557 DECL_UID (lhs))) | |
| 558 continue; | |
| 559 } | |
| 560 } | |
| 561 | |
| 562 if (dump_file && (dump_flags & TDF_DETAILS)) | |
| 563 { | |
| 564 fputs ("va_list escapes in ", dump_file); | |
| 565 print_gimple_stmt (dump_file, stmt, 0, dump_flags); | |
| 566 fputc ('\n', dump_file); | |
| 567 } | |
| 568 return true; | |
| 569 } | |
| 570 } | |
| 571 } | |
| 572 | |
| 573 return false; | |
| 574 } | |
| 575 | |
| 576 | |
| 577 /* Return true if this optimization pass should be done. | |
| 578 It makes only sense for stdarg functions. */ | |
| 579 | |
| 580 static bool | |
| 581 gate_optimize_stdarg (void) | |
| 582 { | |
| 583 /* This optimization is only for stdarg functions. */ | |
| 584 return cfun->stdarg != 0; | |
| 585 } | |
| 586 | |
| 587 | |
| 588 /* Entry point to the stdarg optimization pass. */ | |
| 589 | |
| 590 static unsigned int | |
| 591 execute_optimize_stdarg (void) | |
| 592 { | |
| 593 basic_block bb; | |
| 594 bool va_list_escapes = false; | |
| 595 bool va_list_simple_ptr; | |
| 596 struct stdarg_info si; | |
| 597 struct walk_stmt_info wi; | |
| 598 const char *funcname = NULL; | |
| 599 tree cfun_va_list; | |
| 600 | |
| 601 cfun->va_list_gpr_size = 0; | |
| 602 cfun->va_list_fpr_size = 0; | |
| 603 memset (&si, 0, sizeof (si)); | |
| 604 si.va_list_vars = BITMAP_ALLOC (NULL); | |
| 605 si.va_list_escape_vars = BITMAP_ALLOC (NULL); | |
| 606 | |
| 607 if (dump_file) | |
| 608 funcname = lang_hooks.decl_printable_name (current_function_decl, 2); | |
| 609 | |
| 610 cfun_va_list = targetm.fn_abi_va_list (cfun->decl); | |
| 611 va_list_simple_ptr = POINTER_TYPE_P (cfun_va_list) | |
| 612 && (TREE_TYPE (cfun_va_list) == void_type_node | |
| 613 || TREE_TYPE (cfun_va_list) == char_type_node); | |
| 614 gcc_assert (is_gimple_reg_type (cfun_va_list) == va_list_simple_ptr); | |
| 615 | |
| 616 FOR_EACH_BB (bb) | |
| 617 { | |
| 618 gimple_stmt_iterator i; | |
| 619 | |
| 620 for (i = gsi_start_bb (bb); !gsi_end_p (i); gsi_next (&i)) | |
| 621 { | |
| 622 gimple stmt = gsi_stmt (i); | |
| 623 tree callee, ap; | |
| 624 | |
| 625 if (!is_gimple_call (stmt)) | |
| 626 continue; | |
| 627 | |
| 628 callee = gimple_call_fndecl (stmt); | |
| 629 if (!callee | |
| 630 || DECL_BUILT_IN_CLASS (callee) != BUILT_IN_NORMAL) | |
| 631 continue; | |
| 632 | |
| 633 switch (DECL_FUNCTION_CODE (callee)) | |
| 634 { | |
| 635 case BUILT_IN_VA_START: | |
| 636 break; | |
| 637 /* If old style builtins are used, don't optimize anything. */ | |
| 638 case BUILT_IN_SAVEREGS: | |
| 639 case BUILT_IN_ARGS_INFO: | |
| 640 case BUILT_IN_NEXT_ARG: | |
| 641 va_list_escapes = true; | |
| 642 continue; | |
| 643 default: | |
| 644 continue; | |
| 645 } | |
| 646 | |
| 647 si.va_start_count++; | |
| 648 ap = gimple_call_arg (stmt, 0); | |
| 649 | |
| 650 if (TREE_CODE (ap) != ADDR_EXPR) | |
| 651 { | |
| 652 va_list_escapes = true; | |
| 653 break; | |
| 654 } | |
| 655 ap = TREE_OPERAND (ap, 0); | |
| 656 if (TREE_CODE (ap) == ARRAY_REF) | |
| 657 { | |
| 658 if (! integer_zerop (TREE_OPERAND (ap, 1))) | |
| 659 { | |
| 660 va_list_escapes = true; | |
| 661 break; | |
| 662 } | |
| 663 ap = TREE_OPERAND (ap, 0); | |
| 664 } | |
| 665 if (TYPE_MAIN_VARIANT (TREE_TYPE (ap)) | |
| 666 != TYPE_MAIN_VARIANT (targetm.fn_abi_va_list (cfun->decl)) | |
| 667 || TREE_CODE (ap) != VAR_DECL) | |
| 668 { | |
| 669 va_list_escapes = true; | |
| 670 break; | |
| 671 } | |
| 672 | |
| 673 if (is_global_var (ap)) | |
| 674 { | |
| 675 va_list_escapes = true; | |
| 676 break; | |
| 677 } | |
| 678 | |
| 679 bitmap_set_bit (si.va_list_vars, DECL_UID (ap)); | |
| 680 | |
| 681 /* VA_START_BB and VA_START_AP will be only used if there is just | |
| 682 one va_start in the function. */ | |
| 683 si.va_start_bb = bb; | |
| 684 si.va_start_ap = ap; | |
| 685 } | |
| 686 | |
| 687 if (va_list_escapes) | |
| 688 break; | |
| 689 } | |
| 690 | |
| 691 /* If there were no va_start uses in the function, there is no need to | |
| 692 save anything. */ | |
| 693 if (si.va_start_count == 0) | |
| 694 goto finish; | |
| 695 | |
| 696 /* If some va_list arguments weren't local, we can't optimize. */ | |
| 697 if (va_list_escapes) | |
| 698 goto finish; | |
| 699 | |
| 700 /* For void * or char * va_list, something useful can be done only | |
| 701 if there is just one va_start. */ | |
| 702 if (va_list_simple_ptr && si.va_start_count > 1) | |
| 703 { | |
| 704 va_list_escapes = true; | |
| 705 goto finish; | |
| 706 } | |
| 707 | |
| 708 /* For struct * va_list, if the backend didn't tell us what the counter fields | |
| 709 are, there is nothing more we can do. */ | |
| 710 if (!va_list_simple_ptr | |
| 711 && va_list_gpr_counter_field == NULL_TREE | |
| 712 && va_list_fpr_counter_field == NULL_TREE) | |
| 713 { | |
| 714 va_list_escapes = true; | |
| 715 goto finish; | |
| 716 } | |
| 717 | |
| 718 /* For void * or char * va_list there is just one counter | |
| 719 (va_list itself). Use VA_LIST_GPR_SIZE for it. */ | |
| 720 if (va_list_simple_ptr) | |
| 721 cfun->va_list_fpr_size = VA_LIST_MAX_FPR_SIZE; | |
| 722 | |
| 723 calculate_dominance_info (CDI_DOMINATORS); | |
| 724 memset (&wi, 0, sizeof (wi)); | |
| 725 wi.info = si.va_list_vars; | |
| 726 | |
| 727 FOR_EACH_BB (bb) | |
| 728 { | |
| 729 gimple_stmt_iterator i; | |
| 730 | |
| 731 si.compute_sizes = -1; | |
| 732 si.bb = bb; | |
| 733 | |
| 734 /* For va_list_simple_ptr, we have to check PHI nodes too. We treat | |
| 735 them as assignments for the purpose of escape analysis. This is | |
| 736 not needed for non-simple va_list because virtual phis don't perform | |
| 737 any real data movement. */ | |
| 738 if (va_list_simple_ptr) | |
| 739 { | |
| 740 tree lhs, rhs; | |
| 741 use_operand_p uop; | |
| 742 ssa_op_iter soi; | |
| 743 | |
| 744 for (i = gsi_start_phis (bb); !gsi_end_p (i); gsi_next (&i)) | |
| 745 { | |
| 746 gimple phi = gsi_stmt (i); | |
| 747 lhs = PHI_RESULT (phi); | |
| 748 | |
| 749 if (!is_gimple_reg (lhs)) | |
| 750 continue; | |
| 751 | |
| 752 FOR_EACH_PHI_ARG (uop, phi, soi, SSA_OP_USE) | |
| 753 { | |
| 754 rhs = USE_FROM_PTR (uop); | |
| 755 if (va_list_ptr_read (&si, rhs, lhs)) | |
| 756 continue; | |
| 757 else if (va_list_ptr_write (&si, lhs, rhs)) | |
| 758 continue; | |
| 759 else | |
| 760 check_va_list_escapes (&si, lhs, rhs); | |
| 761 | |
| 762 if (si.va_list_escapes) | |
| 763 { | |
| 764 if (dump_file && (dump_flags & TDF_DETAILS)) | |
| 765 { | |
| 766 fputs ("va_list escapes in ", dump_file); | |
| 767 print_gimple_stmt (dump_file, phi, 0, dump_flags); | |
| 768 fputc ('\n', dump_file); | |
| 769 } | |
| 770 va_list_escapes = true; | |
| 771 } | |
| 772 } | |
| 773 } | |
| 774 } | |
| 775 | |
| 776 for (i = gsi_start_bb (bb); | |
| 777 !gsi_end_p (i) && !va_list_escapes; | |
| 778 gsi_next (&i)) | |
| 779 { | |
| 780 gimple stmt = gsi_stmt (i); | |
| 781 | |
| 782 /* Don't look at __builtin_va_{start,end}, they are ok. */ | |
| 783 if (is_gimple_call (stmt)) | |
| 784 { | |
| 785 tree callee = gimple_call_fndecl (stmt); | |
| 786 | |
| 787 if (callee | |
| 788 && DECL_BUILT_IN_CLASS (callee) == BUILT_IN_NORMAL | |
| 789 && (DECL_FUNCTION_CODE (callee) == BUILT_IN_VA_START | |
| 790 || DECL_FUNCTION_CODE (callee) == BUILT_IN_VA_END)) | |
| 791 continue; | |
| 792 } | |
| 793 | |
| 794 if (is_gimple_assign (stmt)) | |
| 795 { | |
| 796 tree lhs = gimple_assign_lhs (stmt); | |
| 797 tree rhs = gimple_assign_rhs1 (stmt); | |
| 798 | |
| 799 if (va_list_simple_ptr) | |
| 800 { | |
| 801 if (get_gimple_rhs_class (gimple_assign_rhs_code (stmt)) | |
| 802 == GIMPLE_SINGLE_RHS) | |
| 803 { | |
| 804 /* Check for tem = ap. */ | |
| 805 if (va_list_ptr_read (&si, rhs, lhs)) | |
| 806 continue; | |
| 807 | |
| 808 /* Check for the last insn in: | |
| 809 tem1 = ap; | |
| 810 tem2 = tem1 + CST; | |
| 811 ap = tem2; | |
| 812 sequence. */ | |
| 813 else if (va_list_ptr_write (&si, lhs, rhs)) | |
| 814 continue; | |
| 815 } | |
| 816 | |
| 817 if ((gimple_assign_rhs_code (stmt) == POINTER_PLUS_EXPR | |
| 818 && TREE_CODE (gimple_assign_rhs2 (stmt)) == INTEGER_CST) | |
| 819 || CONVERT_EXPR_CODE_P (gimple_assign_rhs_code (stmt)) | |
| 820 || (get_gimple_rhs_class (gimple_assign_rhs_code (stmt)) | |
| 821 == GIMPLE_SINGLE_RHS)) | |
| 822 check_va_list_escapes (&si, lhs, rhs); | |
| 823 } | |
| 824 else | |
| 825 { | |
| 826 if (get_gimple_rhs_class (gimple_assign_rhs_code (stmt)) | |
| 827 == GIMPLE_SINGLE_RHS) | |
| 828 { | |
| 829 /* Check for ap[0].field = temp. */ | |
| 830 if (va_list_counter_struct_op (&si, lhs, rhs, true)) | |
| 831 continue; | |
| 832 | |
| 833 /* Check for temp = ap[0].field. */ | |
| 834 else if (va_list_counter_struct_op (&si, rhs, lhs, | |
| 835 false)) | |
| 836 continue; | |
| 837 } | |
| 838 | |
| 839 /* Do any architecture specific checking. */ | |
| 840 if (targetm.stdarg_optimize_hook | |
| 841 && targetm.stdarg_optimize_hook (&si, stmt)) | |
| 842 continue; | |
| 843 } | |
| 844 } | |
|
55
77e2b8dfacca
update it from 4.4.3 to 4.5.0
ryoma <e075725@ie.u-ryukyu.ac.jp>
parents:
0
diff
changeset
|
845 else if (is_gimple_debug (stmt)) |
|
77e2b8dfacca
update it from 4.4.3 to 4.5.0
ryoma <e075725@ie.u-ryukyu.ac.jp>
parents:
0
diff
changeset
|
846 continue; |
| 0 | 847 |
| 848 /* All other uses of va_list are either va_copy (that is not handled | |
| 849 in this optimization), taking address of va_list variable or | |
| 850 passing va_list to other functions (in that case va_list might | |
| 851 escape the function and therefore va_start needs to set it up | |
| 852 fully), or some unexpected use of va_list. None of these should | |
| 853 happen in a gimplified VA_ARG_EXPR. */ | |
| 854 if (si.va_list_escapes | |
| 855 || walk_gimple_op (stmt, find_va_list_reference, &wi)) | |
| 856 { | |
| 857 if (dump_file && (dump_flags & TDF_DETAILS)) | |
| 858 { | |
| 859 fputs ("va_list escapes in ", dump_file); | |
| 860 print_gimple_stmt (dump_file, stmt, 0, dump_flags); | |
| 861 fputc ('\n', dump_file); | |
| 862 } | |
| 863 va_list_escapes = true; | |
| 864 } | |
| 865 } | |
| 866 | |
| 867 if (va_list_escapes) | |
| 868 break; | |
| 869 } | |
| 870 | |
| 871 if (! va_list_escapes | |
| 872 && va_list_simple_ptr | |
| 873 && ! bitmap_empty_p (si.va_list_escape_vars) | |
| 874 && check_all_va_list_escapes (&si)) | |
| 875 va_list_escapes = true; | |
| 876 | |
| 877 finish: | |
| 878 if (va_list_escapes) | |
| 879 { | |
| 880 cfun->va_list_gpr_size = VA_LIST_MAX_GPR_SIZE; | |
| 881 cfun->va_list_fpr_size = VA_LIST_MAX_FPR_SIZE; | |
| 882 } | |
| 883 BITMAP_FREE (si.va_list_vars); | |
| 884 BITMAP_FREE (si.va_list_escape_vars); | |
| 885 free (si.offsets); | |
| 886 if (dump_file) | |
| 887 { | |
| 888 fprintf (dump_file, "%s: va_list escapes %d, needs to save ", | |
| 889 funcname, (int) va_list_escapes); | |
| 890 if (cfun->va_list_gpr_size >= VA_LIST_MAX_GPR_SIZE) | |
| 891 fputs ("all", dump_file); | |
| 892 else | |
| 893 fprintf (dump_file, "%d", cfun->va_list_gpr_size); | |
| 894 fputs (" GPR units and ", dump_file); | |
| 895 if (cfun->va_list_fpr_size >= VA_LIST_MAX_FPR_SIZE) | |
| 896 fputs ("all", dump_file); | |
| 897 else | |
| 898 fprintf (dump_file, "%d", cfun->va_list_fpr_size); | |
| 899 fputs (" FPR units.\n", dump_file); | |
| 900 } | |
| 901 return 0; | |
| 902 } | |
| 903 | |
| 904 | |
| 905 struct gimple_opt_pass pass_stdarg = | |
| 906 { | |
| 907 { | |
| 908 GIMPLE_PASS, | |
| 909 "stdarg", /* name */ | |
| 910 gate_optimize_stdarg, /* gate */ | |
| 911 execute_optimize_stdarg, /* execute */ | |
| 912 NULL, /* sub */ | |
| 913 NULL, /* next */ | |
| 914 0, /* static_pass_number */ | |
|
55
77e2b8dfacca
update it from 4.4.3 to 4.5.0
ryoma <e075725@ie.u-ryukyu.ac.jp>
parents:
0
diff
changeset
|
915 TV_NONE, /* tv_id */ |
|
77e2b8dfacca
update it from 4.4.3 to 4.5.0
ryoma <e075725@ie.u-ryukyu.ac.jp>
parents:
0
diff
changeset
|
916 PROP_cfg | PROP_ssa, /* properties_required */ |
| 0 | 917 0, /* properties_provided */ |
| 918 0, /* properties_destroyed */ | |
| 919 0, /* todo_flags_start */ | |
| 920 TODO_dump_func /* todo_flags_finish */ | |
| 921 } | |
| 922 }; |