Mercurial > hg > CbC > CbC_gcc
annotate gcc/mode-switching.c @ 56:3c8a44c06a95
Added tag gcc-4.4.5 for changeset 77e2b8dfacca
| author | ryoma <e075725@ie.u-ryukyu.ac.jp> |
|---|---|
| date | Fri, 12 Feb 2010 23:41:23 +0900 |
| parents | 77e2b8dfacca |
| children | b7f97abdc517 |
| rev | line source |
|---|---|
| 0 | 1 /* CPU mode switching |
| 2 Copyright (C) 1998, 1999, 2000, 2001, 2002, 2003, 2004, 2005, 2007, 2008, | |
| 3 2009 Free Software Foundation, Inc. | |
| 4 | |
| 5 This file is part of GCC. | |
| 6 | |
| 7 GCC is free software; you can redistribute it and/or modify it under | |
| 8 the terms of the GNU General Public License as published by the Free | |
| 9 Software Foundation; either version 3, or (at your option) any later | |
| 10 version. | |
| 11 | |
| 12 GCC is distributed in the hope that it will be useful, but WITHOUT ANY | |
| 13 WARRANTY; without even the implied warranty of MERCHANTABILITY or | |
| 14 FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License | |
| 15 for more details. | |
| 16 | |
| 17 You should have received a copy of the GNU General Public License | |
| 18 along with GCC; see the file COPYING3. If not see | |
| 19 <http://www.gnu.org/licenses/>. */ | |
| 20 | |
| 21 #include "config.h" | |
| 22 #include "system.h" | |
| 23 #include "coretypes.h" | |
| 24 #include "tm.h" | |
| 25 #include "rtl.h" | |
| 26 #include "regs.h" | |
| 27 #include "hard-reg-set.h" | |
| 28 #include "flags.h" | |
| 29 #include "real.h" | |
| 30 #include "insn-config.h" | |
| 31 #include "recog.h" | |
| 32 #include "basic-block.h" | |
| 33 #include "output.h" | |
| 34 #include "tm_p.h" | |
| 35 #include "function.h" | |
| 36 #include "tree-pass.h" | |
| 37 #include "timevar.h" | |
| 38 #include "df.h" | |
| 39 | |
| 40 /* We want target macros for the mode switching code to be able to refer | |
| 41 to instruction attribute values. */ | |
| 42 #include "insn-attr.h" | |
| 43 | |
| 44 #ifdef OPTIMIZE_MODE_SWITCHING | |
| 45 | |
| 46 /* The algorithm for setting the modes consists of scanning the insn list | |
| 47 and finding all the insns which require a specific mode. Each insn gets | |
| 48 a unique struct seginfo element. These structures are inserted into a list | |
| 49 for each basic block. For each entity, there is an array of bb_info over | |
| 50 the flow graph basic blocks (local var 'bb_info'), and contains a list | |
| 51 of all insns within that basic block, in the order they are encountered. | |
| 52 | |
| 53 For each entity, any basic block WITHOUT any insns requiring a specific | |
| 54 mode are given a single entry, without a mode. (Each basic block | |
| 55 in the flow graph must have at least one entry in the segment table.) | |
| 56 | |
| 57 The LCM algorithm is then run over the flow graph to determine where to | |
| 58 place the sets to the highest-priority value in respect of first the first | |
| 59 insn in any one block. Any adjustments required to the transparency | |
| 60 vectors are made, then the next iteration starts for the next-lower | |
| 61 priority mode, till for each entity all modes are exhausted. | |
| 62 | |
| 63 More details are located in the code for optimize_mode_switching(). */ | |
| 64 | |
| 65 /* This structure contains the information for each insn which requires | |
| 66 either single or double mode to be set. | |
| 67 MODE is the mode this insn must be executed in. | |
| 68 INSN_PTR is the insn to be executed (may be the note that marks the | |
| 69 beginning of a basic block). | |
| 70 BBNUM is the flow graph basic block this insn occurs in. | |
| 71 NEXT is the next insn in the same basic block. */ | |
| 72 struct seginfo | |
| 73 { | |
| 74 int mode; | |
| 75 rtx insn_ptr; | |
| 76 int bbnum; | |
| 77 struct seginfo *next; | |
| 78 HARD_REG_SET regs_live; | |
| 79 }; | |
| 80 | |
| 81 struct bb_info | |
| 82 { | |
| 83 struct seginfo *seginfo; | |
| 84 int computing; | |
| 85 }; | |
| 86 | |
| 87 /* These bitmaps are used for the LCM algorithm. */ | |
| 88 | |
| 89 static sbitmap *antic; | |
| 90 static sbitmap *transp; | |
| 91 static sbitmap *comp; | |
| 92 | |
| 93 static struct seginfo * new_seginfo (int, rtx, int, HARD_REG_SET); | |
| 94 static void add_seginfo (struct bb_info *, struct seginfo *); | |
| 95 static void reg_dies (rtx, HARD_REG_SET *); | |
| 96 static void reg_becomes_live (rtx, const_rtx, void *); | |
| 97 static void make_preds_opaque (basic_block, int); | |
| 98 | |
| 99 | |
| 100 /* This function will allocate a new BBINFO structure, initialized | |
| 101 with the MODE, INSN, and basic block BB parameters. */ | |
| 102 | |
| 103 static struct seginfo * | |
| 104 new_seginfo (int mode, rtx insn, int bb, HARD_REG_SET regs_live) | |
| 105 { | |
| 106 struct seginfo *ptr; | |
| 107 ptr = XNEW (struct seginfo); | |
| 108 ptr->mode = mode; | |
| 109 ptr->insn_ptr = insn; | |
| 110 ptr->bbnum = bb; | |
| 111 ptr->next = NULL; | |
| 112 COPY_HARD_REG_SET (ptr->regs_live, regs_live); | |
| 113 return ptr; | |
| 114 } | |
| 115 | |
| 116 /* Add a seginfo element to the end of a list. | |
| 117 HEAD is a pointer to the list beginning. | |
| 118 INFO is the structure to be linked in. */ | |
| 119 | |
| 120 static void | |
| 121 add_seginfo (struct bb_info *head, struct seginfo *info) | |
| 122 { | |
| 123 struct seginfo *ptr; | |
| 124 | |
| 125 if (head->seginfo == NULL) | |
| 126 head->seginfo = info; | |
| 127 else | |
| 128 { | |
| 129 ptr = head->seginfo; | |
| 130 while (ptr->next != NULL) | |
| 131 ptr = ptr->next; | |
| 132 ptr->next = info; | |
| 133 } | |
| 134 } | |
| 135 | |
| 136 /* Make all predecessors of basic block B opaque, recursively, till we hit | |
| 137 some that are already non-transparent, or an edge where aux is set; that | |
| 138 denotes that a mode set is to be done on that edge. | |
| 139 J is the bit number in the bitmaps that corresponds to the entity that | |
| 140 we are currently handling mode-switching for. */ | |
| 141 | |
| 142 static void | |
| 143 make_preds_opaque (basic_block b, int j) | |
| 144 { | |
| 145 edge e; | |
| 146 edge_iterator ei; | |
| 147 | |
| 148 FOR_EACH_EDGE (e, ei, b->preds) | |
| 149 { | |
| 150 basic_block pb = e->src; | |
| 151 | |
| 152 if (e->aux || ! TEST_BIT (transp[pb->index], j)) | |
| 153 continue; | |
| 154 | |
| 155 RESET_BIT (transp[pb->index], j); | |
| 156 make_preds_opaque (pb, j); | |
| 157 } | |
| 158 } | |
| 159 | |
| 160 /* Record in LIVE that register REG died. */ | |
| 161 | |
| 162 static void | |
| 163 reg_dies (rtx reg, HARD_REG_SET *live) | |
| 164 { | |
| 165 int regno; | |
| 166 | |
| 167 if (!REG_P (reg)) | |
| 168 return; | |
| 169 | |
| 170 regno = REGNO (reg); | |
| 171 if (regno < FIRST_PSEUDO_REGISTER) | |
| 172 remove_from_hard_reg_set (live, GET_MODE (reg), regno); | |
| 173 } | |
| 174 | |
| 175 /* Record in LIVE that register REG became live. | |
| 176 This is called via note_stores. */ | |
| 177 | |
| 178 static void | |
| 179 reg_becomes_live (rtx reg, const_rtx setter ATTRIBUTE_UNUSED, void *live) | |
| 180 { | |
| 181 int regno; | |
| 182 | |
| 183 if (GET_CODE (reg) == SUBREG) | |
| 184 reg = SUBREG_REG (reg); | |
| 185 | |
| 186 if (!REG_P (reg)) | |
| 187 return; | |
| 188 | |
| 189 regno = REGNO (reg); | |
| 190 if (regno < FIRST_PSEUDO_REGISTER) | |
| 191 add_to_hard_reg_set ((HARD_REG_SET *) live, GET_MODE (reg), regno); | |
| 192 } | |
| 193 | |
| 194 /* Make sure if MODE_ENTRY is defined the MODE_EXIT is defined | |
| 195 and vice versa. */ | |
| 196 #if defined (MODE_ENTRY) != defined (MODE_EXIT) | |
| 197 #error "Both MODE_ENTRY and MODE_EXIT must be defined" | |
| 198 #endif | |
| 199 | |
| 200 #if defined (MODE_ENTRY) && defined (MODE_EXIT) | |
| 201 /* Split the fallthrough edge to the exit block, so that we can note | |
| 202 that there NORMAL_MODE is required. Return the new block if it's | |
| 203 inserted before the exit block. Otherwise return null. */ | |
| 204 | |
| 205 static basic_block | |
| 206 create_pre_exit (int n_entities, int *entity_map, const int *num_modes) | |
| 207 { | |
| 208 edge eg; | |
| 209 edge_iterator ei; | |
| 210 basic_block pre_exit; | |
| 211 | |
| 212 /* The only non-call predecessor at this stage is a block with a | |
| 213 fallthrough edge; there can be at most one, but there could be | |
| 214 none at all, e.g. when exit is called. */ | |
| 215 pre_exit = 0; | |
| 216 FOR_EACH_EDGE (eg, ei, EXIT_BLOCK_PTR->preds) | |
| 217 if (eg->flags & EDGE_FALLTHRU) | |
| 218 { | |
| 219 basic_block src_bb = eg->src; | |
| 220 rtx last_insn, ret_reg; | |
| 221 | |
| 222 gcc_assert (!pre_exit); | |
| 223 /* If this function returns a value at the end, we have to | |
| 224 insert the final mode switch before the return value copy | |
| 225 to its hard register. */ | |
| 226 if (EDGE_COUNT (EXIT_BLOCK_PTR->preds) == 1 | |
| 227 && NONJUMP_INSN_P ((last_insn = BB_END (src_bb))) | |
| 228 && GET_CODE (PATTERN (last_insn)) == USE | |
| 229 && GET_CODE ((ret_reg = XEXP (PATTERN (last_insn), 0))) == REG) | |
| 230 { | |
| 231 int ret_start = REGNO (ret_reg); | |
| 232 int nregs = hard_regno_nregs[ret_start][GET_MODE (ret_reg)]; | |
| 233 int ret_end = ret_start + nregs; | |
| 234 int short_block = 0; | |
| 235 int maybe_builtin_apply = 0; | |
| 236 int forced_late_switch = 0; | |
| 237 rtx before_return_copy; | |
| 238 | |
| 239 do | |
| 240 { | |
| 241 rtx return_copy = PREV_INSN (last_insn); | |
| 242 rtx return_copy_pat, copy_reg; | |
| 243 int copy_start, copy_num; | |
| 244 int j; | |
| 245 | |
| 246 if (INSN_P (return_copy)) | |
| 247 { | |
| 248 /* When using SJLJ exceptions, the call to the | |
| 249 unregister function is inserted between the | |
| 250 clobber of the return value and the copy. | |
| 251 We do not want to split the block before this | |
| 252 or any other call; if we have not found the | |
| 253 copy yet, the copy must have been deleted. */ | |
| 254 if (CALL_P (return_copy)) | |
| 255 { | |
| 256 short_block = 1; | |
| 257 break; | |
| 258 } | |
| 259 return_copy_pat = PATTERN (return_copy); | |
| 260 switch (GET_CODE (return_copy_pat)) | |
| 261 { | |
| 262 case USE: | |
| 263 /* Skip __builtin_apply pattern. */ | |
| 264 if (GET_CODE (XEXP (return_copy_pat, 0)) == REG | |
| 265 && (FUNCTION_VALUE_REGNO_P | |
| 266 (REGNO (XEXP (return_copy_pat, 0))))) | |
| 267 { | |
| 268 maybe_builtin_apply = 1; | |
| 269 last_insn = return_copy; | |
| 270 continue; | |
| 271 } | |
| 272 break; | |
| 273 | |
| 274 case ASM_OPERANDS: | |
| 275 /* Skip barrier insns. */ | |
| 276 if (!MEM_VOLATILE_P (return_copy_pat)) | |
| 277 break; | |
| 278 | |
| 279 /* Fall through. */ | |
| 280 | |
| 281 case ASM_INPUT: | |
| 282 case UNSPEC_VOLATILE: | |
| 283 last_insn = return_copy; | |
| 284 continue; | |
| 285 | |
| 286 default: | |
| 287 break; | |
| 288 } | |
| 289 | |
| 290 /* If the return register is not (in its entirety) | |
| 291 likely spilled, the return copy might be | |
| 292 partially or completely optimized away. */ | |
| 293 return_copy_pat = single_set (return_copy); | |
| 294 if (!return_copy_pat) | |
| 295 { | |
| 296 return_copy_pat = PATTERN (return_copy); | |
| 297 if (GET_CODE (return_copy_pat) != CLOBBER) | |
| 298 break; | |
| 299 else if (!optimize) | |
| 300 { | |
| 301 /* This might be (clobber (reg [<result>])) | |
| 302 when not optimizing. Then check if | |
| 303 the previous insn is the clobber for | |
| 304 the return register. */ | |
| 305 copy_reg = SET_DEST (return_copy_pat); | |
| 306 if (GET_CODE (copy_reg) == REG | |
| 307 && !HARD_REGISTER_NUM_P (REGNO (copy_reg))) | |
| 308 { | |
| 309 if (INSN_P (PREV_INSN (return_copy))) | |
| 310 { | |
| 311 return_copy = PREV_INSN (return_copy); | |
| 312 return_copy_pat = PATTERN (return_copy); | |
| 313 if (GET_CODE (return_copy_pat) != CLOBBER) | |
| 314 break; | |
| 315 } | |
| 316 } | |
| 317 } | |
| 318 } | |
| 319 copy_reg = SET_DEST (return_copy_pat); | |
| 320 if (GET_CODE (copy_reg) == REG) | |
| 321 copy_start = REGNO (copy_reg); | |
| 322 else if (GET_CODE (copy_reg) == SUBREG | |
| 323 && GET_CODE (SUBREG_REG (copy_reg)) == REG) | |
| 324 copy_start = REGNO (SUBREG_REG (copy_reg)); | |
| 325 else | |
| 326 break; | |
| 327 if (copy_start >= FIRST_PSEUDO_REGISTER) | |
| 328 break; | |
| 329 copy_num | |
| 330 = hard_regno_nregs[copy_start][GET_MODE (copy_reg)]; | |
| 331 | |
| 332 /* If the return register is not likely spilled, - as is | |
| 333 the case for floating point on SH4 - then it might | |
| 334 be set by an arithmetic operation that needs a | |
| 335 different mode than the exit block. */ | |
| 336 for (j = n_entities - 1; j >= 0; j--) | |
| 337 { | |
| 338 int e = entity_map[j]; | |
| 339 int mode = MODE_NEEDED (e, return_copy); | |
| 340 | |
| 341 if (mode != num_modes[e] && mode != MODE_EXIT (e)) | |
| 342 break; | |
| 343 } | |
| 344 if (j >= 0) | |
| 345 { | |
| 346 /* For the SH4, floating point loads depend on fpscr, | |
| 347 thus we might need to put the final mode switch | |
| 348 after the return value copy. That is still OK, | |
| 349 because a floating point return value does not | |
| 350 conflict with address reloads. */ | |
| 351 if (copy_start >= ret_start | |
| 352 && copy_start + copy_num <= ret_end | |
| 353 && OBJECT_P (SET_SRC (return_copy_pat))) | |
| 354 forced_late_switch = 1; | |
| 355 break; | |
| 356 } | |
| 357 | |
| 358 if (copy_start >= ret_start | |
| 359 && copy_start + copy_num <= ret_end) | |
| 360 nregs -= copy_num; | |
| 361 else if (!maybe_builtin_apply | |
| 362 || !FUNCTION_VALUE_REGNO_P (copy_start)) | |
| 363 break; | |
| 364 last_insn = return_copy; | |
| 365 } | |
| 366 /* ??? Exception handling can lead to the return value | |
| 367 copy being already separated from the return value use, | |
| 368 as in unwind-dw2.c . | |
| 369 Similarly, conditionally returning without a value, | |
| 370 and conditionally using builtin_return can lead to an | |
| 371 isolated use. */ | |
| 372 if (return_copy == BB_HEAD (src_bb)) | |
| 373 { | |
| 374 short_block = 1; | |
| 375 break; | |
| 376 } | |
| 377 last_insn = return_copy; | |
| 378 } | |
| 379 while (nregs); | |
|
55
77e2b8dfacca
update it from 4.4.3 to 4.5.0
ryoma <e075725@ie.u-ryukyu.ac.jp>
parents:
0
diff
changeset
|
380 |
| 0 | 381 /* If we didn't see a full return value copy, verify that there |
| 382 is a plausible reason for this. If some, but not all of the | |
| 383 return register is likely spilled, we can expect that there | |
| 384 is a copy for the likely spilled part. */ | |
| 385 gcc_assert (!nregs | |
| 386 || forced_late_switch | |
| 387 || short_block | |
| 388 || !(CLASS_LIKELY_SPILLED_P | |
| 389 (REGNO_REG_CLASS (ret_start))) | |
| 390 || (nregs | |
| 391 != hard_regno_nregs[ret_start][GET_MODE (ret_reg)]) | |
| 392 /* For multi-hard-register floating point | |
| 393 values, sometimes the likely-spilled part | |
| 394 is ordinarily copied first, then the other | |
| 395 part is set with an arithmetic operation. | |
| 396 This doesn't actually cause reload | |
| 397 failures, so let it pass. */ | |
| 398 || (GET_MODE_CLASS (GET_MODE (ret_reg)) != MODE_INT | |
| 399 && nregs != 1)); | |
|
55
77e2b8dfacca
update it from 4.4.3 to 4.5.0
ryoma <e075725@ie.u-ryukyu.ac.jp>
parents:
0
diff
changeset
|
400 |
| 0 | 401 if (INSN_P (last_insn)) |
| 402 { | |
| 403 before_return_copy | |
| 404 = emit_note_before (NOTE_INSN_DELETED, last_insn); | |
| 405 /* Instructions preceding LAST_INSN in the same block might | |
| 406 require a different mode than MODE_EXIT, so if we might | |
| 407 have such instructions, keep them in a separate block | |
| 408 from pre_exit. */ | |
| 409 if (last_insn != BB_HEAD (src_bb)) | |
| 410 src_bb = split_block (src_bb, | |
| 411 PREV_INSN (before_return_copy))->dest; | |
| 412 } | |
| 413 else | |
| 414 before_return_copy = last_insn; | |
| 415 pre_exit = split_block (src_bb, before_return_copy)->src; | |
| 416 } | |
| 417 else | |
| 418 { | |
| 419 pre_exit = split_edge (eg); | |
| 420 } | |
| 421 } | |
| 422 | |
| 423 return pre_exit; | |
| 424 } | |
| 425 #endif | |
| 426 | |
| 427 /* Find all insns that need a particular mode setting, and insert the | |
| 428 necessary mode switches. Return true if we did work. */ | |
| 429 | |
| 430 static int | |
| 431 optimize_mode_switching (void) | |
| 432 { | |
| 433 rtx insn; | |
| 434 int e; | |
| 435 basic_block bb; | |
| 436 int need_commit = 0; | |
| 437 sbitmap *kill; | |
| 438 struct edge_list *edge_list; | |
| 439 static const int num_modes[] = NUM_MODES_FOR_MODE_SWITCHING; | |
| 440 #define N_ENTITIES ARRAY_SIZE (num_modes) | |
| 441 int entity_map[N_ENTITIES]; | |
| 442 struct bb_info *bb_info[N_ENTITIES]; | |
| 443 int i, j; | |
| 444 int n_entities; | |
| 445 int max_num_modes = 0; | |
| 446 bool emited = false; | |
| 447 basic_block post_entry ATTRIBUTE_UNUSED, pre_exit ATTRIBUTE_UNUSED; | |
| 448 | |
| 449 for (e = N_ENTITIES - 1, n_entities = 0; e >= 0; e--) | |
| 450 if (OPTIMIZE_MODE_SWITCHING (e)) | |
| 451 { | |
| 452 int entry_exit_extra = 0; | |
| 453 | |
| 454 /* Create the list of segments within each basic block. | |
| 455 If NORMAL_MODE is defined, allow for two extra | |
| 456 blocks split from the entry and exit block. */ | |
| 457 #if defined (MODE_ENTRY) && defined (MODE_EXIT) | |
| 458 entry_exit_extra = 3; | |
| 459 #endif | |
| 460 bb_info[n_entities] | |
| 461 = XCNEWVEC (struct bb_info, last_basic_block + entry_exit_extra); | |
| 462 entity_map[n_entities++] = e; | |
| 463 if (num_modes[e] > max_num_modes) | |
| 464 max_num_modes = num_modes[e]; | |
| 465 } | |
| 466 | |
| 467 if (! n_entities) | |
| 468 return 0; | |
| 469 | |
| 470 #if defined (MODE_ENTRY) && defined (MODE_EXIT) | |
| 471 /* Split the edge from the entry block, so that we can note that | |
| 472 there NORMAL_MODE is supplied. */ | |
| 473 post_entry = split_edge (single_succ_edge (ENTRY_BLOCK_PTR)); | |
| 474 pre_exit = create_pre_exit (n_entities, entity_map, num_modes); | |
| 475 #endif | |
| 476 | |
| 477 df_analyze (); | |
| 478 | |
| 479 /* Create the bitmap vectors. */ | |
| 480 | |
| 481 antic = sbitmap_vector_alloc (last_basic_block, n_entities); | |
| 482 transp = sbitmap_vector_alloc (last_basic_block, n_entities); | |
| 483 comp = sbitmap_vector_alloc (last_basic_block, n_entities); | |
| 484 | |
| 485 sbitmap_vector_ones (transp, last_basic_block); | |
| 486 | |
| 487 for (j = n_entities - 1; j >= 0; j--) | |
| 488 { | |
| 489 int e = entity_map[j]; | |
| 490 int no_mode = num_modes[e]; | |
| 491 struct bb_info *info = bb_info[j]; | |
| 492 | |
| 493 /* Determine what the first use (if any) need for a mode of entity E is. | |
| 494 This will be the mode that is anticipatable for this block. | |
| 495 Also compute the initial transparency settings. */ | |
| 496 FOR_EACH_BB (bb) | |
| 497 { | |
| 498 struct seginfo *ptr; | |
| 499 int last_mode = no_mode; | |
| 500 HARD_REG_SET live_now; | |
| 501 | |
| 502 REG_SET_TO_HARD_REG_SET (live_now, df_get_live_in (bb)); | |
| 503 | |
| 504 /* Pretend the mode is clobbered across abnormal edges. */ | |
| 505 { | |
| 506 edge_iterator ei; | |
| 507 edge e; | |
| 508 FOR_EACH_EDGE (e, ei, bb->preds) | |
| 509 if (e->flags & EDGE_COMPLEX) | |
| 510 break; | |
| 511 if (e) | |
| 512 { | |
| 513 ptr = new_seginfo (no_mode, BB_HEAD (bb), bb->index, live_now); | |
| 514 add_seginfo (info + bb->index, ptr); | |
| 515 RESET_BIT (transp[bb->index], j); | |
| 516 } | |
| 517 } | |
| 518 | |
| 519 for (insn = BB_HEAD (bb); | |
| 520 insn != NULL && insn != NEXT_INSN (BB_END (bb)); | |
| 521 insn = NEXT_INSN (insn)) | |
| 522 { | |
| 523 if (INSN_P (insn)) | |
| 524 { | |
| 525 int mode = MODE_NEEDED (e, insn); | |
| 526 rtx link; | |
| 527 | |
| 528 if (mode != no_mode && mode != last_mode) | |
| 529 { | |
| 530 last_mode = mode; | |
| 531 ptr = new_seginfo (mode, insn, bb->index, live_now); | |
| 532 add_seginfo (info + bb->index, ptr); | |
| 533 RESET_BIT (transp[bb->index], j); | |
| 534 } | |
| 535 #ifdef MODE_AFTER | |
| 536 last_mode = MODE_AFTER (last_mode, insn); | |
| 537 #endif | |
| 538 /* Update LIVE_NOW. */ | |
| 539 for (link = REG_NOTES (insn); link; link = XEXP (link, 1)) | |
| 540 if (REG_NOTE_KIND (link) == REG_DEAD) | |
| 541 reg_dies (XEXP (link, 0), &live_now); | |
| 542 | |
| 543 note_stores (PATTERN (insn), reg_becomes_live, &live_now); | |
| 544 for (link = REG_NOTES (insn); link; link = XEXP (link, 1)) | |
| 545 if (REG_NOTE_KIND (link) == REG_UNUSED) | |
| 546 reg_dies (XEXP (link, 0), &live_now); | |
| 547 } | |
| 548 } | |
| 549 | |
| 550 info[bb->index].computing = last_mode; | |
| 551 /* Check for blocks without ANY mode requirements. */ | |
| 552 if (last_mode == no_mode) | |
| 553 { | |
| 554 ptr = new_seginfo (no_mode, BB_END (bb), bb->index, live_now); | |
| 555 add_seginfo (info + bb->index, ptr); | |
| 556 } | |
| 557 } | |
| 558 #if defined (MODE_ENTRY) && defined (MODE_EXIT) | |
| 559 { | |
| 560 int mode = MODE_ENTRY (e); | |
| 561 | |
| 562 if (mode != no_mode) | |
| 563 { | |
| 564 bb = post_entry; | |
| 565 | |
| 566 /* By always making this nontransparent, we save | |
| 567 an extra check in make_preds_opaque. We also | |
| 568 need this to avoid confusing pre_edge_lcm when | |
| 569 antic is cleared but transp and comp are set. */ | |
| 570 RESET_BIT (transp[bb->index], j); | |
| 571 | |
| 572 /* Insert a fake computing definition of MODE into entry | |
| 573 blocks which compute no mode. This represents the mode on | |
| 574 entry. */ | |
| 575 info[bb->index].computing = mode; | |
| 576 | |
| 577 if (pre_exit) | |
| 578 info[pre_exit->index].seginfo->mode = MODE_EXIT (e); | |
| 579 } | |
| 580 } | |
| 581 #endif /* NORMAL_MODE */ | |
| 582 } | |
| 583 | |
| 584 kill = sbitmap_vector_alloc (last_basic_block, n_entities); | |
| 585 for (i = 0; i < max_num_modes; i++) | |
| 586 { | |
| 587 int current_mode[N_ENTITIES]; | |
| 588 sbitmap *del; | |
| 589 sbitmap *insert; | |
| 590 | |
| 591 /* Set the anticipatable and computing arrays. */ | |
| 592 sbitmap_vector_zero (antic, last_basic_block); | |
| 593 sbitmap_vector_zero (comp, last_basic_block); | |
| 594 for (j = n_entities - 1; j >= 0; j--) | |
| 595 { | |
| 596 int m = current_mode[j] = MODE_PRIORITY_TO_MODE (entity_map[j], i); | |
| 597 struct bb_info *info = bb_info[j]; | |
| 598 | |
| 599 FOR_EACH_BB (bb) | |
| 600 { | |
| 601 if (info[bb->index].seginfo->mode == m) | |
| 602 SET_BIT (antic[bb->index], j); | |
| 603 | |
| 604 if (info[bb->index].computing == m) | |
| 605 SET_BIT (comp[bb->index], j); | |
| 606 } | |
| 607 } | |
| 608 | |
| 609 /* Calculate the optimal locations for the | |
| 610 placement mode switches to modes with priority I. */ | |
| 611 | |
| 612 FOR_EACH_BB (bb) | |
| 613 sbitmap_not (kill[bb->index], transp[bb->index]); | |
| 614 edge_list = pre_edge_lcm (n_entities, transp, comp, antic, | |
| 615 kill, &insert, &del); | |
| 616 | |
| 617 for (j = n_entities - 1; j >= 0; j--) | |
| 618 { | |
| 619 /* Insert all mode sets that have been inserted by lcm. */ | |
| 620 int no_mode = num_modes[entity_map[j]]; | |
| 621 | |
| 622 /* Wherever we have moved a mode setting upwards in the flow graph, | |
| 623 the blocks between the new setting site and the now redundant | |
| 624 computation ceases to be transparent for any lower-priority | |
| 625 mode of the same entity. First set the aux field of each | |
| 626 insertion site edge non-transparent, then propagate the new | |
| 627 non-transparency from the redundant computation upwards till | |
| 628 we hit an insertion site or an already non-transparent block. */ | |
| 629 for (e = NUM_EDGES (edge_list) - 1; e >= 0; e--) | |
| 630 { | |
| 631 edge eg = INDEX_EDGE (edge_list, e); | |
| 632 int mode; | |
| 633 basic_block src_bb; | |
| 634 HARD_REG_SET live_at_edge; | |
| 635 rtx mode_set; | |
| 636 | |
| 637 eg->aux = 0; | |
| 638 | |
| 639 if (! TEST_BIT (insert[e], j)) | |
| 640 continue; | |
| 641 | |
| 642 eg->aux = (void *)1; | |
| 643 | |
| 644 mode = current_mode[j]; | |
| 645 src_bb = eg->src; | |
| 646 | |
| 647 REG_SET_TO_HARD_REG_SET (live_at_edge, df_get_live_out (src_bb)); | |
| 648 | |
| 649 start_sequence (); | |
| 650 EMIT_MODE_SET (entity_map[j], mode, live_at_edge); | |
| 651 mode_set = get_insns (); | |
| 652 end_sequence (); | |
| 653 | |
| 654 /* Do not bother to insert empty sequence. */ | |
| 655 if (mode_set == NULL_RTX) | |
| 656 continue; | |
| 657 | |
| 658 /* We should not get an abnormal edge here. */ | |
| 659 gcc_assert (! (eg->flags & EDGE_ABNORMAL)); | |
| 660 | |
| 661 need_commit = 1; | |
| 662 insert_insn_on_edge (mode_set, eg); | |
| 663 } | |
| 664 | |
| 665 FOR_EACH_BB_REVERSE (bb) | |
| 666 if (TEST_BIT (del[bb->index], j)) | |
| 667 { | |
| 668 make_preds_opaque (bb, j); | |
| 669 /* Cancel the 'deleted' mode set. */ | |
| 670 bb_info[j][bb->index].seginfo->mode = no_mode; | |
| 671 } | |
| 672 } | |
| 673 | |
| 674 sbitmap_vector_free (del); | |
| 675 sbitmap_vector_free (insert); | |
| 676 clear_aux_for_edges (); | |
| 677 free_edge_list (edge_list); | |
| 678 } | |
| 679 | |
| 680 /* Now output the remaining mode sets in all the segments. */ | |
| 681 for (j = n_entities - 1; j >= 0; j--) | |
| 682 { | |
| 683 int no_mode = num_modes[entity_map[j]]; | |
| 684 | |
| 685 FOR_EACH_BB_REVERSE (bb) | |
| 686 { | |
| 687 struct seginfo *ptr, *next; | |
| 688 for (ptr = bb_info[j][bb->index].seginfo; ptr; ptr = next) | |
| 689 { | |
| 690 next = ptr->next; | |
| 691 if (ptr->mode != no_mode) | |
| 692 { | |
| 693 rtx mode_set; | |
| 694 | |
| 695 start_sequence (); | |
| 696 EMIT_MODE_SET (entity_map[j], ptr->mode, ptr->regs_live); | |
| 697 mode_set = get_insns (); | |
| 698 end_sequence (); | |
| 699 | |
| 700 /* Insert MODE_SET only if it is nonempty. */ | |
| 701 if (mode_set != NULL_RTX) | |
| 702 { | |
| 703 emited = true; | |
| 704 if (NOTE_INSN_BASIC_BLOCK_P (ptr->insn_ptr)) | |
| 705 emit_insn_after (mode_set, ptr->insn_ptr); | |
| 706 else | |
| 707 emit_insn_before (mode_set, ptr->insn_ptr); | |
| 708 } | |
| 709 } | |
| 710 | |
| 711 free (ptr); | |
| 712 } | |
| 713 } | |
| 714 | |
| 715 free (bb_info[j]); | |
| 716 } | |
| 717 | |
| 718 /* Finished. Free up all the things we've allocated. */ | |
| 719 sbitmap_vector_free (kill); | |
| 720 sbitmap_vector_free (antic); | |
| 721 sbitmap_vector_free (transp); | |
| 722 sbitmap_vector_free (comp); | |
| 723 | |
| 724 if (need_commit) | |
| 725 commit_edge_insertions (); | |
| 726 | |
| 727 #if defined (MODE_ENTRY) && defined (MODE_EXIT) | |
| 728 cleanup_cfg (CLEANUP_NO_INSN_DEL); | |
| 729 #else | |
| 730 if (!need_commit && !emited) | |
| 731 return 0; | |
| 732 #endif | |
| 733 | |
| 734 return 1; | |
| 735 } | |
| 736 | |
| 737 #endif /* OPTIMIZE_MODE_SWITCHING */ | |
| 738 | |
| 739 static bool | |
| 740 gate_mode_switching (void) | |
| 741 { | |
| 742 #ifdef OPTIMIZE_MODE_SWITCHING | |
| 743 return true; | |
| 744 #else | |
| 745 return false; | |
| 746 #endif | |
| 747 } | |
| 748 | |
| 749 static unsigned int | |
| 750 rest_of_handle_mode_switching (void) | |
| 751 { | |
| 752 #ifdef OPTIMIZE_MODE_SWITCHING | |
| 753 optimize_mode_switching (); | |
| 754 #endif /* OPTIMIZE_MODE_SWITCHING */ | |
| 755 return 0; | |
| 756 } | |
| 757 | |
| 758 | |
| 759 struct rtl_opt_pass pass_mode_switching = | |
| 760 { | |
| 761 { | |
| 762 RTL_PASS, | |
| 763 "mode_sw", /* name */ | |
| 764 gate_mode_switching, /* gate */ | |
| 765 rest_of_handle_mode_switching, /* execute */ | |
| 766 NULL, /* sub */ | |
| 767 NULL, /* next */ | |
| 768 0, /* static_pass_number */ | |
| 769 TV_MODE_SWITCH, /* tv_id */ | |
| 770 0, /* properties_required */ | |
| 771 0, /* properties_provided */ | |
| 772 0, /* properties_destroyed */ | |
| 773 0, /* todo_flags_start */ | |
| 774 TODO_df_finish | TODO_verify_rtl_sharing | | |
| 775 TODO_dump_func /* todo_flags_finish */ | |
| 776 } | |
| 777 }; |