| File: | src/of_cprop.c |
| Warning: | line 973, column 3 Value stored to 'bb' is never read |
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| 1 | /***************************************************************************** |
| 2 | * |
| 3 | * of_cprop.c: Copy Propagation |
| 4 | * |
| 5 | * Copyright (c) 1990-2007 Aldor Software Organization Ltd (Aldor.org). |
| 6 | * |
| 7 | ****************************************************************************/ |
| 8 | /*************************************************************************** |
| 9 | * |
| 10 | * Copy propagation optimization |
| 11 | * |
| 12 | * (Refer. to 'Aho, Sethi, Ullman: "Compilers: Principles, Techinques, |
| 13 | * and Tools", Addison Wesley) |
| 14 | * |
| 15 | * The implementation of this optimization is really close to the |
| 16 | * algorithm used for UD chains (see top of usedef.c file) |
| 17 | * The main differences are: |
| 18 | * |
| 19 | * - VarCopiesVect[i] is the list of all the copies where (Loc i) is |
| 20 | * lhs or rhs (in usedef is only lhs) |
| 21 | * - Sets Gen and Kill are build in a slightly different way. |
| 22 | * - During phase (3), instead of attaching definitions on each usage, |
| 23 | * copy propagation is performed. Each usage of (Loc i) such that there |
| 24 | * is a unique copy in its reachingDefs list is substitued with the rhs |
| 25 | * of the copy. |
| 26 | * |
| 27 | * Implementation notes: |
| 28 | * |
| 29 | * - Once the dflow analysis has been performed, cpCopyPropagate is called. |
| 30 | * For each block, cpCopyPropagate0 is called on the corresponding foam |
| 31 | * tree. The algorithm try to substitute an usage skipping all the |
| 32 | * intermediate copies. |
| 33 | * Consider, in example, the following sequence: |
| 34 | * (L1 := L0), (L2 := L1), (L3 := L2), foo(L3) |
| 35 | * In this case, the rightmost occurrence of L3 is initially replaced |
| 36 | * by L2; in the second step L2 is replaced by L1, finally with L0. |
| 37 | * Therefore foo(L3) will become foo(L0). |
| 38 | * |
| 39 | ************************************************************************* |
| 40 | * |
| 41 | * DEFINITIONS |
| 42 | * |
| 43 | * For the current implementation: |
| 44 | * - a TMPVAR is a Loc or a Par. |
| 45 | * - a IMMEDIATE is SInt, Char, Bool, Byte, etc. (see cpIsImmediate) |
| 46 | * - a DEFinition is a Def or a Set stmt. of kind: |
| 47 | * (DEF TMPVAR expr) |
| 48 | * or |
| 49 | * (DEF (Values ...) expr) |
| 50 | * |
| 51 | * - CopyableCast is of the form (Cast type TMPVAR) |
| 52 | * |
| 53 | * - a COPY is a stmt. of kind: |
| 54 | * (DEF TMPVAR TMPVAR) |
| 55 | * or |
| 56 | * (DEF TMPVAR (Cast type TMPVAR)) |
| 57 | * or |
| 58 | * (DEF TMPVAR IMMEDIATE) |
| 59 | * or |
| 60 | * (DEF TMPVAR (Cast type IMMEDIATE)) |
| 61 | * |
| 62 | * |
| 63 | *************************************************************************/ |
| 64 | |
| 65 | #include "debug.h" |
| 66 | #include "dflow.h" |
| 67 | #include "flog.h" |
| 68 | #include "of_cprop.h" |
| 69 | #include "of_peep.h" |
| 70 | #include "of_util.h" |
| 71 | #include "optfoam.h" |
| 72 | #include "optinfo.h" |
| 73 | #include "opttools.h" |
| 74 | #include "store.h" |
| 75 | #include "bigint.h" |
| 76 | |
| 77 | /**************************************************************************** |
| 78 | * :: Macros |
| 79 | ****************************************************************************/ |
| 80 | |
| 81 | # define cpIsTmpVar(var)(((var)->hdr.tag) == FOAM_Loc || ((var)->hdr.tag) == FOAM_Par ) (foamTag(var)((var)->hdr.tag) == FOAM_Loc || foamTag(var)((var)->hdr.tag) == FOAM_Par) |
| 82 | |
| 83 | # define cpIsTmpVarOrValues(foam)((((foam)->hdr.tag) == FOAM_Loc || ((foam)->hdr.tag) == FOAM_Par) || ((foam)->hdr.tag)==FOAM_Values) (cpIsTmpVar(foam)(((foam)->hdr.tag) == FOAM_Loc || ((foam)->hdr.tag) == FOAM_Par ) || \ |
| 84 | foamTag(foam)((foam)->hdr.tag)==FOAM_Values) |
| 85 | |
| 86 | # define cpIsSpecialCast(foam)((foam)->foamCast.type == FOAM_SFlo) ((foam)->foamCast.type == FOAM_SFlo) |
| 87 | |
| 88 | # define cpIsCopyableCast(foam)(((foam)->hdr.tag)==FOAM_Cast && !((foam)->foamCast .type == FOAM_SFlo) && ((((foam->foamCast.expr)-> hdr.tag) == FOAM_Loc || ((foam->foamCast.expr)->hdr.tag ) == FOAM_Par) || cpIsImmediate(foam->foamCast.expr))) (foamTag(foam)((foam)->hdr.tag)==FOAM_Cast && \ |
| 89 | !cpIsSpecialCast(foam)((foam)->foamCast.type == FOAM_SFlo) && \ |
| 90 | (cpIsTmpVar(foam->foamCast.expr)(((foam->foamCast.expr)->hdr.tag) == FOAM_Loc || ((foam ->foamCast.expr)->hdr.tag) == FOAM_Par) || \ |
| 91 | cpIsImmediate(foam->foamCast.expr))) |
| 92 | |
| 93 | # define cpIsCopy(foam)(cpIsDef(foam) && cpDefIsCopy(foam)) (cpIsDef(foam) && cpDefIsCopy(foam)) |
| 94 | |
| 95 | |
| 96 | #define cpDF_CUTOFF200 200 /* Max no dataflow iterations to converge. */ |
| 97 | |
| 98 | # define cpDefNo(foam)((foam)->foamGen.hdr.info.defNo) ((foam)->foamGen.hdr.info.defNo) |
| 99 | |
| 100 | /* given a (Loc) or a (Par), assign to varno the index in the varDefsVect */ |
| 101 | # define cpGetVarNo(varno, foamVar)if (((foamVar)->hdr.tag) == FOAM_Par) (varno) = (foamVar)-> foamPar.index + cpInfo.nLocals; else (varno) = (foamVar)-> foamLoc.index; \ |
| 102 | if (foamTag(foamVar)((foamVar)->hdr.tag) == FOAM_Par) \ |
| 103 | (varno) = (foamVar)->foamPar.index + cpInfo.nLocals;\ |
| 104 | else \ |
| 105 | (varno) = (foamVar)->foamLoc.index; |
| 106 | |
| 107 | /**************************************************************************** |
| 108 | * :: Debug |
| 109 | ****************************************************************************/ |
| 110 | |
| 111 | Bool cpDfDebug = false((int) 0); |
| 112 | Bool cpDebug = false((int) 0); |
| 113 | |
| 114 | #define cpDfDEBUGif (!cpDfDebug) { } else afprintf DEBUG_IF(cpDf)if (!cpDfDebug) { } else afprintf |
| 115 | #define cpDEBUGif (!cpDebug) { } else afprintf DEBUG_IF(cp)if (!cpDebug) { } else afprintf |
| 116 | |
| 117 | /**************************************************************************** |
| 118 | * :: Global Data Structures |
| 119 | ****************************************************************************/ |
| 120 | |
| 121 | typedef struct { |
| 122 | FoamList * varCopiesVect; |
| 123 | int nParams; |
| 124 | int nLocals; |
| 125 | int nCopies; |
| 126 | |
| 127 | int nPropagated; |
| 128 | |
| 129 | BitvClass bitvClass; |
| 130 | } CpInfo; |
| 131 | |
| 132 | static CpInfo cpInfo; |
| 133 | static Bool cpFirstTime; |
| 134 | |
| 135 | /* maybe a bitmap ? */ |
| 136 | typedef enum { CP_Lhs, CP_Rhs, CP_CEnv } CpFlagState; |
| 137 | |
| 138 | /**************************************************************************** |
| 139 | * |
| 140 | * :: Local prototypes |
| 141 | * |
| 142 | ****************************************************************************/ |
| 143 | |
| 144 | localstatic Foam cpProg (Foam); |
| 145 | |
| 146 | localstatic void cpFlog0 (FlowGraph); |
| 147 | |
| 148 | localstatic void cpVarCopiesVectBuild (Foam); |
| 149 | localstatic void cpVarCopiesVectUpdate (Foam); |
| 150 | localstatic void cpVarCopiesVectFree (void); |
| 151 | extern void cpVarCopiesVectPrint (void); |
| 152 | |
| 153 | localstatic Bool cpIsDef (Foam); |
| 154 | localstatic Bool cpDefIsCopy (Foam); |
| 155 | localstatic Bool cpIsImmediate (Foam); |
| 156 | localstatic Foam cpRhsVarFrCopy (Foam); |
| 157 | |
| 158 | localstatic void cpFillGenKill (FlowGraph, BBlock); |
| 159 | localstatic void cpSetKillCopies (Bitv, Foam, int, Bool); |
| 160 | |
| 161 | localstatic void cpCopyPropagate (FlowGraph); |
| 162 | localstatic Foam cpCopyPropagate0 (Foam, Bitv, CpFlagState); |
| 163 | |
| 164 | localstatic void cpProgInit (Foam); |
| 165 | localstatic void cpProgFini (void); |
| 166 | |
| 167 | localstatic void acFoldAssignments (FlowGraph); |
| 168 | |
| 169 | |
| 170 | /**************************************************************************** |
| 171 | * |
| 172 | * :: External entry points |
| 173 | * |
| 174 | ****************************************************************************/ |
| 175 | |
| 176 | void |
| 177 | cpropUnit(Foam foam, Bool isFirst) |
| 178 | { |
| 179 | Foam defs, def; |
| 180 | int i; |
| 181 | |
| 182 | assert(foamTag(foam) == FOAM_Unit)do { if (!(((foam)->hdr.tag) == FOAM_Unit)) _do_assert(("foamTag(foam) == FOAM_Unit" ),"of_cprop.c",182); } while (0); |
| 183 | |
| 184 | cpFirstTime = isFirst; |
| 185 | |
| 186 | defs = foam->foamUnit.defs; |
| 187 | |
| 188 | for (i = 0; i < foamArgc(defs)((defs)->hdr.argc); i++) { |
| 189 | |
| 190 | def = defs->foamDDef.argv[i]; |
| 191 | |
| 192 | assert(foamTag(def) == FOAM_Def)do { if (!(((def)->hdr.tag) == FOAM_Def)) _do_assert(("foamTag(def) == FOAM_Def" ),"of_cprop.c",192); } while (0); |
| 193 | if (foamTag(def->foamDef.rhs)((def->foamDef.rhs)->hdr.tag) != FOAM_Prog) |
| 194 | continue; |
| 195 | |
| 196 | def->foamDef.rhs = cpProg(def->foamDef.rhs); |
| 197 | |
| 198 | if (DEBUG(cpDf)cpDfDebug) { |
| 199 | if (cpInfo.nCopies) { |
| 200 | fprintf(dbOut, "------ New prog: -----\n"); |
| 201 | foamPrintDb(def->foamDef.rhs); |
| 202 | } |
| 203 | } |
| 204 | |
| 205 | /* flogFree(flog); !! no flogFree, write it */ |
| 206 | } |
| 207 | } |
| 208 | |
| 209 | /* Given a flow graph, perform copy propagation on it. |
| 210 | * NOTE: Assumes that flog comes from a Prog. |
| 211 | */ |
| 212 | Bool |
| 213 | cpFlog(FlowGraph flog) |
| 214 | { |
| 215 | Bool result = false((int) 0); |
| 216 | |
| 217 | Foam prog = flog->prog; |
| 218 | |
| 219 | assert(foamTag(prog) == FOAM_Prog)do { if (!(((prog)->hdr.tag) == FOAM_Prog)) _do_assert(("foamTag(prog) == FOAM_Prog" ),"of_cprop.c",219); } while (0); |
| 220 | |
| 221 | cpProgInit(prog); |
| 222 | |
| 223 | if (cpInfo.nLocals + cpInfo.nParams == 0) { |
| 224 | cpProgFini(); |
| 225 | return false((int) 0); |
| 226 | } |
| 227 | |
| 228 | flogIter(flog, bb, {{ { int _i; BBlock bb; for (_i = 0; _i < ((flog)->blocks ->pos); _i++) { bb = bbufBlockFn((flog)->blocks,_i); if (!bb) continue; { { cpVarCopiesVectBuild(bb->code); }; }; } }; } |
| 229 | cpVarCopiesVectBuild(bb->code);{ { int _i; BBlock bb; for (_i = 0; _i < ((flog)->blocks ->pos); _i++) { bb = bbufBlockFn((flog)->blocks,_i); if (!bb) continue; { { cpVarCopiesVectBuild(bb->code); }; }; } }; } |
| 230 | }){ { int _i; BBlock bb; for (_i = 0; _i < ((flog)->blocks ->pos); _i++) { bb = bbufBlockFn((flog)->blocks,_i); if (!bb) continue; { { cpVarCopiesVectBuild(bb->code); }; }; } }; }; |
| 231 | |
| 232 | if (cpInfo.nCopies) { |
| 233 | flogReuse(flog, FLOG_UniqueExit); |
| 234 | cpFlog0(flog); |
| 235 | } |
| 236 | |
| 237 | cpProgFini(); |
| 238 | |
| 239 | result = cpInfo.nPropagated > 0; |
| 240 | |
| 241 | return result; |
| 242 | } |
| 243 | |
| 244 | /**************************************************************************** |
| 245 | * |
| 246 | * :: cpProg |
| 247 | * |
| 248 | ****************************************************************************/ |
| 249 | |
| 250 | localstatic Foam |
| 251 | cpProg(Foam foam) |
| 252 | { |
| 253 | FlowGraph flog; |
| 254 | Foam newProg; |
| 255 | |
| 256 | assert(foamTag(foam) == FOAM_Prog)do { if (!(((foam)->hdr.tag) == FOAM_Prog)) _do_assert(("foamTag(foam) == FOAM_Prog" ),"of_cprop.c",256); } while (0); |
| 257 | |
| 258 | if (!optIsCPropPending(foam)(((foam)->hdr.info.opt)->optMask & (1 << 0))) return foam; |
| 259 | if (!cpFirstTime) |
| 260 | optResetCPropPending(foam)(((foam)->hdr.info.opt)->optMask &= ~(1 << 0) ); |
| 261 | |
| 262 | cpProgInit(foam); |
| 263 | |
| 264 | if (cpInfo.nLocals + cpInfo.nParams == 0) { |
| 265 | cpProgFini(); |
| 266 | return foam; |
| 267 | } |
| 268 | |
| 269 | cpVarCopiesVectBuild(foam->foamProg.body); |
| 270 | |
| 271 | if (cpInfo.nCopies == 0) |
| 272 | return foam; |
| 273 | |
| 274 | flog = flogFrProg(foam, FLOG_UniqueExit); |
| 275 | |
| 276 | cpFlog0(flog); |
| 277 | |
| 278 | newProg = flogToProg(flog); |
| 279 | |
| 280 | if (cpInfo.nPropagated > 0) { |
| 281 | optSetPeepPending(newProg)(((newProg)->hdr.info.opt)->optMask |= (1 << 4)); |
| 282 | optSetJFlowPending(newProg)(((newProg)->hdr.info.opt)->optMask |= (1 << 1)); |
| 283 | optSetCsePending(newProg)(((newProg)->hdr.info.opt)->optMask |= (1 << 2)); |
| 284 | /* newProg = peepProg(newProg); */ |
| 285 | } |
| 286 | |
| 287 | cpProgFini(); |
| 288 | |
| 289 | return newProg; |
| 290 | } |
| 291 | |
| 292 | /* |
| 293 | * Apply copy propagation to flog |
| 294 | */ |
| 295 | localstatic void |
| 296 | cpFlog0(FlowGraph flog) |
| 297 | { |
| 298 | BBlock bb; |
| 299 | int i, k; |
| 300 | |
| 301 | if (false((int) 0)) |
| 302 | acFoldAssignments(flog); |
| 303 | |
| 304 | flogBitvClass(flog)((flog)->bitvClass) = bitvClassCreate(cpInfo.nCopies); |
| 305 | cpInfo.bitvClass = flogBitvClass(flog)((flog)->bitvClass); |
| 306 | |
| 307 | for (i = 0; i < flogBlockC(flog)((flog)->blocks->pos); i++) { |
| 308 | bb = flogBlock(flog, i)bbufBlockFn((flog)->blocks,i); |
| 309 | if (!bb || bb->dfinfo) continue; |
| 310 | dflowNewBlockInfo(bb, cpInfo.nCopies, cpFillGenKill); |
| 311 | } |
| 312 | |
| 313 | i = dflowFwdIterate(flog, DFLOW_Intersection, cpDF_CUTOFF200, &k, NULL((void*)0)); |
| 314 | |
| 315 | if (DEBUG(cpDf)cpDfDebug) { |
| 316 | fprintf(dbOut, i == 0 ? "Converged" : "Did not converge"); |
| 317 | fprintf(dbOut, " after %d iterations\n", k); |
| 318 | flogPrint(dbOut, flog, true1); |
| 319 | } |
| 320 | |
| 321 | if (i != 0) return; |
| 322 | |
| 323 | cpCopyPropagate(flog); |
| 324 | |
| 325 | dflowFreeGraphInfo(flog); |
| 326 | } |
| 327 | |
| 328 | /**************************************************************************** |
| 329 | * |
| 330 | * :: Local function |
| 331 | * |
| 332 | ****************************************************************************/ |
| 333 | |
| 334 | |
| 335 | /* Assign a progressive number to each copy, and add it to varCopiesVect |
| 336 | * in the entries corresponding to the lhs and the rhs. |
| 337 | * This info will be used in the dflow analysis. |
| 338 | */ |
| 339 | localstatic void |
| 340 | cpVarCopiesVectBuild(Foam seq) |
| 341 | { |
| 342 | Foam stmt; |
| 343 | int i; |
| 344 | |
| 345 | assert(foamTag(seq) == FOAM_Seq)do { if (!(((seq)->hdr.tag) == FOAM_Seq)) _do_assert(("foamTag(seq) == FOAM_Seq" ),"of_cprop.c",345); } while (0); |
| 346 | |
| 347 | for (i = 0; i < foamArgc(seq)((seq)->hdr.argc); i++) { |
| 348 | stmt = foamArgv(seq)((seq)->foamGen.argv)[i].code; |
| 349 | |
| 350 | if (cpIsCopy(stmt)(cpIsDef(stmt) && cpDefIsCopy(stmt))) { |
| 351 | cpDefNo(stmt)((stmt)->foamGen.hdr.info.defNo) = cpInfo.nCopies++; |
| 352 | cpVarCopiesVectUpdate(stmt); |
| 353 | } |
| 354 | } |
| 355 | |
| 356 | if (DEBUG(cpDf)cpDfDebug) { |
| 357 | cpVarCopiesVectPrint(); |
| 358 | } |
| 359 | |
| 360 | return; |
| 361 | } |
| 362 | |
| 363 | localstatic void |
| 364 | cpVarCopiesVectUpdate(Foam def) |
| 365 | { |
| 366 | Foam lhs = def->foamDef.lhs; |
| 367 | Foam rhs; |
| 368 | int varNo; |
| 369 | |
| 370 | assert(foamTag(lhs) == FOAM_Loc || foamTag(lhs) == FOAM_Par)do { if (!(((lhs)->hdr.tag) == FOAM_Loc || ((lhs)->hdr. tag) == FOAM_Par)) _do_assert(("foamTag(lhs) == FOAM_Loc || foamTag(lhs) == FOAM_Par" ),"of_cprop.c",370); } while (0); |
| 371 | |
| 372 | cpGetVarNo(varNo, lhs)if (((lhs)->hdr.tag) == FOAM_Par) (varNo) = (lhs)->foamPar .index + cpInfo.nLocals; else (varNo) = (lhs)->foamLoc.index ;; |
| 373 | |
| 374 | assert(varNo < cpInfo.nLocals + cpInfo.nParams)do { if (!(varNo < cpInfo.nLocals + cpInfo.nParams)) _do_assert (("varNo < cpInfo.nLocals + cpInfo.nParams"),"of_cprop.c", 374); } while (0); |
| 375 | |
| 376 | cpInfo.varCopiesVect[varNo] = listCons(Foam)(Foam_listPointer->Cons) |
| 377 | (foamCopy(def), cpInfo.varCopiesVect[varNo]); |
| 378 | |
| 379 | cpInfo.nCopies += 1; |
| 380 | |
| 381 | rhs = cpRhsVarFrCopy(def); |
| 382 | |
| 383 | if (!rhs) |
| 384 | return; |
| 385 | |
| 386 | cpGetVarNo(varNo, rhs)if (((rhs)->hdr.tag) == FOAM_Par) (varNo) = (rhs)->foamPar .index + cpInfo.nLocals; else (varNo) = (rhs)->foamLoc.index ;; |
| 387 | |
| 388 | assert(varNo < cpInfo.nLocals + cpInfo.nParams)do { if (!(varNo < cpInfo.nLocals + cpInfo.nParams)) _do_assert (("varNo < cpInfo.nLocals + cpInfo.nParams"),"of_cprop.c", 388); } while (0); |
| 389 | |
| 390 | cpInfo.varCopiesVect[varNo] = listCons(Foam)(Foam_listPointer->Cons) |
| 391 | (foamCopy(def), cpInfo.varCopiesVect[varNo]); |
| 392 | } |
| 393 | |
| 394 | localstatic void |
| 395 | cpVarCopiesVectFree() |
| 396 | { |
| 397 | int i, totVars = cpInfo.nLocals + cpInfo.nParams; |
| 398 | |
| 399 | if (!cpInfo.varCopiesVect) return; |
| 400 | |
| 401 | for (i = 0; i < totVars; i++) |
| 402 | listFreeDeeply(Foam)(Foam_listPointer->FreeDeeply)(cpInfo.varCopiesVect[i], foamFree); |
| 403 | |
| 404 | stoFree(cpInfo.varCopiesVect); |
| 405 | } |
| 406 | |
| 407 | void |
| 408 | cpVarCopiesVectPrint() |
| 409 | { |
| 410 | FoamList fl; |
| 411 | int nLoc = cpInfo.nLocals; |
| 412 | int nPar = cpInfo.nParams; |
| 413 | int i; |
| 414 | |
| 415 | fprintf(dbOut, "**** varCopiesVect ****\n"); |
| 416 | |
| 417 | for (i = 0; i < nLoc; i++) { |
| 418 | if (!cpInfo.varCopiesVect[i]) continue; |
| 419 | fprintf(dbOut, "Loc %d:", i); |
| 420 | for (fl = cpInfo.varCopiesVect[i]; fl ; fl = cdr(fl)((fl)->rest)) |
| 421 | foamPrintDb(car(fl)((fl)->first)); |
| 422 | } |
| 423 | for (i = 0; i < nPar; i++) { |
| 424 | if (!cpInfo.varCopiesVect[i + nLoc]) continue; |
| 425 | fprintf(dbOut, "Par %d:", i); |
| 426 | for (fl = cpInfo.varCopiesVect[i + nLoc]; fl ; fl = cdr(fl)((fl)->rest)) |
| 427 | foamPrintDb(car(fl)((fl)->first)); |
| 428 | } |
| 429 | } |
| 430 | |
| 431 | /**************************************************************************** |
| 432 | * |
| 433 | * :: Utility |
| 434 | * |
| 435 | ****************************************************************************/ |
| 436 | |
| 437 | localstatic Bool |
| 438 | cpIsDef(Foam foam) |
| 439 | { |
| 440 | Foam lhs; |
| 441 | |
| 442 | if (foamTag(foam)((foam)->hdr.tag) != FOAM_Def && |
| 443 | foamTag(foam)((foam)->hdr.tag) != FOAM_Set) |
| 444 | return false((int) 0); |
| 445 | |
| 446 | lhs = foam->foamDef.lhs; |
| 447 | |
| 448 | if (!cpIsTmpVarOrValues(lhs)((((lhs)->hdr.tag) == FOAM_Loc || ((lhs)->hdr.tag) == FOAM_Par ) || ((lhs)->hdr.tag)==FOAM_Values)) |
| 449 | return false((int) 0); |
| 450 | |
| 451 | return true1; |
| 452 | } |
| 453 | |
| 454 | localstatic Bool |
| 455 | cpDefIsCopy(Foam foam) |
| 456 | { |
| 457 | Foam rhs; |
| 458 | |
| 459 | assert(foamTag(foam) == FOAM_Def || foamTag(foam) == FOAM_Set)do { if (!(((foam)->hdr.tag) == FOAM_Def || ((foam)->hdr .tag) == FOAM_Set)) _do_assert(("foamTag(foam) == FOAM_Def || foamTag(foam) == FOAM_Set" ),"of_cprop.c",459); } while (0); |
| 460 | |
| 461 | if (foamTag(foam->foamDef.lhs)((foam->foamDef.lhs)->hdr.tag) == FOAM_Values) |
| 462 | return false((int) 0); |
| 463 | |
| 464 | rhs = foam->foamDef.rhs; |
| 465 | |
| 466 | if (foamTag(rhs)((rhs)->hdr.tag) != FOAM_Loc && |
| 467 | foamTag(rhs)((rhs)->hdr.tag) != FOAM_Par && |
| 468 | #if 1 |
| 469 | foamTag(rhs)((rhs)->hdr.tag) != FOAM_Clos && |
| 470 | #endif |
| 471 | !cpIsImmediate(rhs) && |
| 472 | !cpIsCopyableCast(rhs)(((rhs)->hdr.tag)==FOAM_Cast && !((rhs)->foamCast .type == FOAM_SFlo) && ((((rhs->foamCast.expr)-> hdr.tag) == FOAM_Loc || ((rhs->foamCast.expr)->hdr.tag) == FOAM_Par) || cpIsImmediate(rhs->foamCast.expr)))) |
| 473 | return false((int) 0); |
| 474 | |
| 475 | return true1; |
| 476 | } |
| 477 | |
| 478 | /* FOAM is generally the rhs of a definition. |
| 479 | * Returns true if FOAM is an immediate data or a cast of it |
| 480 | * |
| 481 | * Note: DFlo, BInt, Rec, Arr, Prog and Clos are not immediate data. |
| 482 | * Roughly speaking, an immediate data is a data such that a foam expr |
| 483 | * like: |
| 484 | * (Seq (Set Loc0 DATA) (use Loc0) (use Loc0)) |
| 485 | * is semantically equivalent to: |
| 486 | * (Seq (use DATA) (use DATA)) |
| 487 | * Note: RRFmt is considered immediate, as are Type* and SizeOf* bcalls. |
| 488 | */ |
| 489 | localstatic Bool |
| 490 | cpIsImmediate(Foam foam) |
| 491 | { |
| 492 | Bool result = false((int) 0); |
| 493 | |
| 494 | while (foamTag(foam)((foam)->hdr.tag) == FOAM_Cast) |
| 495 | foam = foam->foamCast.expr; |
| 496 | |
| 497 | if (foamTag(foam)((foam)->hdr.tag) == FOAM_BInt) { |
| 498 | result = bintIsZero(foam->foamBInt.BIntData) || |
| 499 | bintEQ(foam->foamBInt.BIntData, bint1); |
| 500 | } |
| 501 | else if (foamTag(foam)((foam)->hdr.tag) == FOAM_BCall) { |
| 502 | /* |
| 503 | * We want to fold RawRepSize and Type* calls |
| 504 | * into RRFmt instructions (their primary use). |
| 505 | * This allows RRFmt values to be examined in |
| 506 | * detail: for example, RRFmts whose arguments |
| 507 | * do not refer to locs, lex or globs ought to |
| 508 | * be lifted to the start of progs and units. |
| 509 | * (see of_rrfmt for more details). |
| 510 | * |
| 511 | * Note that SizeOf* and Type* calls correspond to |
| 512 | * integer values which can be computed cheaply. |
| 513 | * Also, while RawRepSize values must be computed |
| 514 | * at runtime, they are constant and relatively |
| 515 | * cheap to compute. |
| 516 | */ |
| 517 | FoamBValTag tag = foam->foamBCall.op; |
| 518 | |
| 519 | switch (tag) { |
| 520 | case FOAM_BVal_RawRepSize: result = true1;break; |
| 521 | #if 0 |
| 522 | case FOAM_BVal_SizeOfInt8: /* Fall through */ |
| 523 | case FOAM_BVal_SizeOfInt16: /* Fall through */ |
| 524 | case FOAM_BVal_SizeOfInt32: /* Fall through */ |
| 525 | case FOAM_BVal_SizeOfInt64: /* Fall through */ |
| 526 | case FOAM_BVal_SizeOfInt128: /* Fall through */ |
| 527 | #endif |
| 528 | case FOAM_BVal_SizeOfNil: /* Fall through */ |
| 529 | case FOAM_BVal_SizeOfChar: /* Fall through */ |
| 530 | case FOAM_BVal_SizeOfBool: /* Fall through */ |
| 531 | case FOAM_BVal_SizeOfByte: /* Fall through */ |
| 532 | case FOAM_BVal_SizeOfHInt: /* Fall through */ |
| 533 | case FOAM_BVal_SizeOfSInt: /* Fall through */ |
| 534 | case FOAM_BVal_SizeOfBInt: /* Fall through */ |
| 535 | case FOAM_BVal_SizeOfSFlo: /* Fall through */ |
| 536 | case FOAM_BVal_SizeOfDFlo: /* Fall through */ |
| 537 | case FOAM_BVal_SizeOfWord: /* Fall through */ |
| 538 | case FOAM_BVal_SizeOfClos: /* Fall through */ |
| 539 | case FOAM_BVal_SizeOfPtr: /* Fall through */ |
| 540 | case FOAM_BVal_SizeOfRec: /* Fall through */ |
| 541 | case FOAM_BVal_SizeOfArr: /* Fall through */ |
| 542 | case FOAM_BVal_SizeOfTR: result = true1; break; |
| 543 | |
| 544 | #if 0 |
| 545 | case FOAM_BVal_TypeInt8: /* Fall through */ |
| 546 | case FOAM_BVal_TypeInt16: /* Fall through */ |
| 547 | case FOAM_BVal_TypeInt32: /* Fall through */ |
| 548 | case FOAM_BVal_TypeInt64: /* Fall through */ |
| 549 | case FOAM_BVal_TypeInt128: /* Fall through */ |
| 550 | #endif |
| 551 | case FOAM_BVal_TypeNil: /* Fall through */ |
| 552 | case FOAM_BVal_TypeChar: /* Fall through */ |
| 553 | case FOAM_BVal_TypeBool: /* Fall through */ |
| 554 | case FOAM_BVal_TypeByte: /* Fall through */ |
| 555 | case FOAM_BVal_TypeHInt: /* Fall through */ |
| 556 | case FOAM_BVal_TypeSInt: /* Fall through */ |
| 557 | case FOAM_BVal_TypeBInt: /* Fall through */ |
| 558 | case FOAM_BVal_TypeSFlo: /* Fall through */ |
| 559 | case FOAM_BVal_TypeDFlo: /* Fall through */ |
| 560 | case FOAM_BVal_TypeWord: /* Fall through */ |
| 561 | case FOAM_BVal_TypeClos: /* Fall through */ |
| 562 | case FOAM_BVal_TypePtr: /* Fall through */ |
| 563 | case FOAM_BVal_TypeRec: /* Fall through */ |
| 564 | case FOAM_BVal_TypeArr: /* Fall through */ |
| 565 | case FOAM_BVal_TypeTR: result = true1; break; |
| 566 | default: result = false((int) 0); break; |
| 567 | } |
| 568 | } |
| 569 | else { |
| 570 | result = (foamTag(foam)((foam)->hdr.tag) == FOAM_SInt || |
| 571 | foamTag(foam)((foam)->hdr.tag) == FOAM_Char || |
| 572 | foamTag(foam)((foam)->hdr.tag) == FOAM_Bool || |
| 573 | foamTag(foam)((foam)->hdr.tag) == FOAM_Byte || |
| 574 | foamTag(foam)((foam)->hdr.tag) == FOAM_HInt || |
| 575 | foamTag(foam)((foam)->hdr.tag) == FOAM_SFlo || |
| 576 | foamTag(foam)((foam)->hdr.tag) == FOAM_Nil || |
| 577 | foamTag(foam)((foam)->hdr.tag) == FOAM_RRFmt || |
| 578 | foamTag(foam)((foam)->hdr.tag) == FOAM_Env); |
| 579 | } |
| 580 | |
| 581 | return result; |
| 582 | } |
| 583 | |
| 584 | /* Given a copy, returns NULL if the rhs is not a (casted) tmpvar, |
| 585 | * the tmpvar elsewhere. |
| 586 | */ |
| 587 | localstatic Foam |
| 588 | cpRhsVarFrCopy(Foam copy) |
| 589 | { |
| 590 | Foam rhs; |
| 591 | |
| 592 | if (cpIsTmpVar(copy)(((copy)->hdr.tag) == FOAM_Loc || ((copy)->hdr.tag) == FOAM_Par )) |
| 593 | return copy->foamDef.rhs; |
| 594 | |
| 595 | rhs = copy->foamDef.rhs; |
| 596 | |
| 597 | if (foamTag(rhs)((rhs)->hdr.tag) == FOAM_Cast) |
| 598 | rhs = rhs->foamCast.expr; |
| 599 | |
| 600 | if (cpIsTmpVar(rhs)(((rhs)->hdr.tag) == FOAM_Loc || ((rhs)->hdr.tag) == FOAM_Par )) |
| 601 | return rhs; |
| 602 | |
| 603 | return NULL((void*)0); |
| 604 | } |
| 605 | /**************************************************************************** |
| 606 | * |
| 607 | * :: Build Gen and Kill sets |
| 608 | * |
| 609 | ****************************************************************************/ |
| 610 | |
| 611 | localstatic void |
| 612 | cpFillGenKill(FlowGraph flog, BBlock bb) |
| 613 | { |
| 614 | Foam seq = bb->code, stmt; |
| 615 | int defNo, i; |
| 616 | BitvClass class = cpInfo.bitvClass; |
| 617 | |
| 618 | assert(class == bbBitvClass(bb))do { if (!(class == ((((bb)->graph)->bitvClass)))) _do_assert (("class == bbBitvClass(bb)"),"of_cprop.c",618); } while (0); |
| 619 | |
| 620 | /* |
| 621 | * Clear the vectors. |
| 622 | */ |
| 623 | bitvClearAll(class, dfFwdGen(bb)((bb)->dfinfo->gen)); |
| 624 | bitvClearAll(class, dfFwdKill(bb, int0)((bb)->dfinfo->exit[((int) 0)].kill)); |
| 625 | |
| 626 | for (i = 0; i < foamArgc(seq)((seq)->hdr.argc); i++) { |
| 627 | stmt = foamArgv(seq)((seq)->foamGen.argv)[i].code; |
| 628 | |
| 629 | if (!cpIsDef(stmt)) |
| 630 | continue; |
| 631 | |
| 632 | defNo = cpDefNo(stmt)((stmt)->foamGen.hdr.info.defNo); |
| 633 | |
| 634 | cpSetKillCopies(dfFwdKill(bb, int0)((bb)->dfinfo->exit[((int) 0)].kill), stmt, defNo, true1); |
| 635 | |
| 636 | if (cpDefIsCopy(stmt)) { |
| 637 | /* Set gen bit for the corresponding def */ |
| 638 | bitvSet(class, dfFwdGen(bb)((bb)->dfinfo->gen), defNo); |
| 639 | /* Unkill, needed because we use (IN \/ Gen) - Kill */ |
| 640 | bitvClear(class, dfFwdKill(bb, int0)((bb)->dfinfo->exit[((int) 0)].kill), defNo); |
| 641 | } |
| 642 | |
| 643 | } |
| 644 | } |
| 645 | |
| 646 | localstatic void |
| 647 | cpSetKillCopies(Bitv statev, Foam def, int defNo, Bool bit) |
| 648 | { |
| 649 | int varNo, n, var, nVars; |
| 650 | FoamList defs; |
| 651 | Foam lhs = def->foamDef.lhs; |
| 652 | Foam * lhsVarVect; |
| 653 | BitvClass class = cpInfo.bitvClass; |
| 654 | |
| 655 | assert(cpIsTmpVarOrValues(lhs))do { if (!(((((lhs)->hdr.tag) == FOAM_Loc || ((lhs)->hdr .tag) == FOAM_Par) || ((lhs)->hdr.tag)==FOAM_Values))) _do_assert (("cpIsTmpVarOrValues(lhs)"),"of_cprop.c",655); } while (0); |
| 656 | |
| 657 | if (foamTag(lhs)((lhs)->hdr.tag) == FOAM_Values) { |
| 658 | nVars = foamArgc(lhs)((lhs)->hdr.argc); |
| 659 | lhsVarVect = lhs->foamValues.argv; |
| 660 | } |
| 661 | else { |
| 662 | nVars = 1; |
| 663 | lhsVarVect = &lhs; |
| 664 | } |
| 665 | |
| 666 | for (var = 0; var < nVars; var++) { |
| 667 | |
| 668 | lhs = lhsVarVect[var]; |
| 669 | |
| 670 | if (!cpIsTmpVar(lhs)(((lhs)->hdr.tag) == FOAM_Loc || ((lhs)->hdr.tag) == FOAM_Par )) |
| 671 | continue; |
| 672 | |
| 673 | cpGetVarNo(varNo, lhs)if (((lhs)->hdr.tag) == FOAM_Par) (varNo) = (lhs)->foamPar .index + cpInfo.nLocals; else (varNo) = (lhs)->foamLoc.index ;; |
| 674 | |
| 675 | defs = cpInfo.varCopiesVect[varNo]; |
| 676 | |
| 677 | for ( ; defs ; defs = cdr(defs)((defs)->rest)) { |
| 678 | n = cpDefNo(car(defs))((((defs)->first))->foamGen.hdr.info.defNo); |
| 679 | if (bit) |
| 680 | bitvSet(class, statev, n); |
| 681 | else |
| 682 | bitvClear(class, statev, n); |
| 683 | } |
| 684 | } |
| 685 | |
| 686 | return; |
| 687 | } |
| 688 | |
| 689 | /**************************************************************************** |
| 690 | * |
| 691 | * :: Foam traversal and copy propagation |
| 692 | * |
| 693 | ****************************************************************************/ |
| 694 | |
| 695 | localstatic void |
| 696 | cpCopyPropagate(FlowGraph flog) |
| 697 | { |
| 698 | BBlock bb; |
| 699 | int i; |
| 700 | |
| 701 | for (i = 0; i < flogBlockC(flog)((flog)->blocks->pos); i++) { |
| 702 | bb = flogBlock(flog, i)bbufBlockFn((flog)->blocks,i); |
| 703 | if (!bb) continue; |
| 704 | if (bbEntryC(bb)((bb)->entries->pos) == 0 && !bb->isblock0) continue; |
| 705 | |
| 706 | bb->code = cpCopyPropagate0(bb->code, dfFwdIn(bb)((bb)->dfinfo->in), CP_Rhs); |
| 707 | |
| 708 | if (DEBUG(cpDf)cpDfDebug) { |
| 709 | foamPrintDb(bb->code); |
| 710 | } |
| 711 | } |
| 712 | } |
| 713 | |
| 714 | localstatic Foam |
| 715 | cpCopyPropagate0(Foam foam, Bitv dfin, CpFlagState cpState) |
| 716 | { |
| 717 | Foam newFoam = foam; |
| 718 | Bool isDef = false((int) 0); |
| 719 | |
| 720 | if (otIsDef(foam)(((foam)->hdr.tag) == FOAM_Set || ((foam)->hdr.tag) == FOAM_Def )) { |
| 721 | Foam lhs, rhs; |
| 722 | isDef = cpDefIsCopy(foam); |
| 723 | |
| 724 | foam->foamDef.rhs = cpCopyPropagate0(foam->foamDef.rhs, dfin, |
| 725 | CP_Rhs); |
| 726 | foam->foamDef.lhs = cpCopyPropagate0(foam->foamDef.lhs, dfin, |
| 727 | CP_Lhs); |
| 728 | |
| 729 | lhs = foam->foamDef.lhs; |
| 730 | rhs = foam->foamDef.rhs; |
| 731 | |
| 732 | /* Remove (Set (Loc n) (Loc n)) that might appear |
| 733 | * after a propagation. */ |
| 734 | |
| 735 | if (foamTag(lhs)((lhs)->hdr.tag) == foamTag(rhs)((rhs)->hdr.tag) && |
| 736 | cpIsTmpVar(lhs)(((lhs)->hdr.tag) == FOAM_Loc || ((lhs)->hdr.tag) == FOAM_Par ) && |
| 737 | lhs->foamLoc.index == rhs->foamLoc.index) { |
| 738 | |
| 739 | foamFree(foam); |
| 740 | return foamNewNOp()foamNew(FOAM_NOp, (int) 0); |
| 741 | } |
| 742 | } |
| 743 | else if (foamTag(foam)((foam)->hdr.tag) == FOAM_CEnv) { |
| 744 | Foam clos = cpCopyPropagate0(foam->foamCEnv.env, dfin, CP_CEnv); |
| 745 | /* Should check that clos->env is a constant */ |
| 746 | if (foamTag(clos)((clos)->hdr.tag) == FOAM_Clos) |
| 747 | return clos->foamClos.env; |
| 748 | return foam; |
| 749 | } |
| 750 | else if (foamTag(foam)((foam)->hdr.tag) == FOAM_Values && cpState == CP_Lhs) |
| 751 | return foam; |
| 752 | else foamIter(foam, arg, *arg = cpCopyPropagate0(*arg, dfin, CP_Rhs); ){ { String argf = (foamInfoTable [(int)(((foam)->hdr.tag)) -(int)FOAM_START]).argf; Length _i; for (_i = 0; _i < ((foam )->hdr.argc); _i++, argf++) { if (*argf == '*') argf--; if (*argf == 'C') { Foam *arg = (Foam *) ((foam)->foamGen.argv )+_i; { *arg = cpCopyPropagate0(*arg, dfin, CP_Rhs);; }; } } } ; }; |
| 753 | |
| 754 | |
| 755 | switch (foamTag(foam)((foam)->hdr.tag)) { |
| 756 | case FOAM_Loc: |
| 757 | case FOAM_Par: { |
| 758 | int defNo, varNo, index; |
| 759 | FoamList defs; |
| 760 | Foam def, copy, lhs, rhsVar; |
| 761 | Bool unique, foundLoop = false((int) 0); |
| 762 | AInt castType = FOAM_Nil; |
| 763 | |
| 764 | if (cpState == CP_Lhs) break; |
| 765 | |
| 766 | while (!foundLoop && foam) { |
| 767 | copy = NULL((void*)0); |
| 768 | |
| 769 | cpGetVarNo(varNo, foam)if (((foam)->hdr.tag) == FOAM_Par) (varNo) = (foam)->foamPar .index + cpInfo.nLocals; else (varNo) = (foam)->foamLoc.index ;; |
| 770 | index = foam->foamLoc.index; |
| 771 | |
| 772 | /* Look which copies are alive at this point */ |
| 773 | defs = cpInfo.varCopiesVect[varNo]; |
| 774 | |
| 775 | for (unique = true1; defs && unique; defs = cdr(defs)((defs)->rest)) { |
| 776 | def = car(defs)((defs)->first); |
| 777 | defNo = cpDefNo(def)((def)->foamGen.hdr.info.defNo); |
| 778 | lhs = def->foamDef.lhs; |
| 779 | |
| 780 | /* Still alive ? */ |
| 781 | if (!bitvTest(cpInfo.bitvClass, dfin, defNo)) |
| 782 | continue; |
| 783 | |
| 784 | /* Is the same lhs ? */ |
| 785 | if (index == lhs->foamLoc.index && |
| 786 | foamTag(lhs)((lhs)->hdr.tag) == foamTag(foam)((foam)->hdr.tag)) { |
| 787 | if (copy) unique = false((int) 0); |
| 788 | copy = def; |
| 789 | } |
| 790 | } |
| 791 | |
| 792 | /* Found a unique copy ? */ |
| 793 | if (!copy || !unique) break; |
| 794 | |
| 795 | rhsVar = cpRhsVarFrCopy(copy); |
| 796 | if (cpState != CP_CEnv && rhsVar && foamTag(rhsVar)((rhsVar)->hdr.tag) == FOAM_Clos) |
| 797 | break; |
| 798 | |
| 799 | if (cpState != CP_CEnv && foamTag(copy->foamDef.rhs)((copy->foamDef.rhs)->hdr.tag) == FOAM_Clos) |
| 800 | break; |
| 801 | |
| 802 | if (foamTag(copy->foamDef.rhs)((copy->foamDef.rhs)->hdr.tag) == FOAM_Cast && |
| 803 | castType == FOAM_Nil) |
| 804 | castType = copy->foamDef.rhs->foamCast.type; |
| 805 | |
| 806 | /* It's a loop? (Set (Loc 0) (Loc 0)) is a loop. */ |
| 807 | if (rhsVar && index == rhsVar->foamLoc.index && |
| 808 | foamTag(foam)((foam)->hdr.tag) == foamTag(rhsVar)((rhsVar)->hdr.tag)) |
| 809 | foundLoop = true1; |
| 810 | |
| 811 | /* Is the unique copy/definition reaching this point. |
| 812 | * Substitution can be performed. |
| 813 | */ |
| 814 | |
| 815 | /* foamFree(foam); */ |
| 816 | |
| 817 | newFoam = foamCopy(copy->foamDef.rhs); |
| 818 | cpInfo.nPropagated += 1; |
| 819 | |
| 820 | cpDEBUGif (!cpDebug) { } else afprintf(dbOut, "CPROP>> Copy propagated ---\n"); |
| 821 | |
| 822 | foam = rhsVar; /* Will be NULL if rhs is IMMEDIATE */ |
| 823 | } |
| 824 | |
| 825 | |
| 826 | /* "castType" is used to handle situations like: |
| 827 | * l6 -> (Cast Word l5) |
| 828 | * l5 -> (Cast SInt l3) |
| 829 | * In this case l6 should be substitued by (Cast Word l3). |
| 830 | * "castType" keeps trace of the first cast type. |
| 831 | */ |
| 832 | |
| 833 | if (castType != FOAM_Nil) |
| 834 | newFoam = foamNewCast(castType, newFoam)foamNew(FOAM_Cast, 2, castType, newFoam); |
| 835 | |
| 836 | |
| 837 | break; |
| 838 | } |
| 839 | |
| 840 | case FOAM_Set: |
| 841 | case FOAM_Def: { |
| 842 | Foam lhs = foam->foamDef.lhs; |
| 843 | int defNo; |
| 844 | |
| 845 | /* Update the IN vector */ |
| 846 | |
| 847 | if (!cpIsTmpVarOrValues(lhs)((((lhs)->hdr.tag) == FOAM_Loc || ((lhs)->hdr.tag) == FOAM_Par ) || ((lhs)->hdr.tag)==FOAM_Values)) |
| 848 | break; |
| 849 | |
| 850 | defNo = cpDefNo(foam)((foam)->foamGen.hdr.info.defNo); |
| 851 | cpSetKillCopies(dfin, foam, defNo, false((int) 0)); |
| 852 | |
| 853 | /* |
| 854 | * !!NB: cpDefIsCopy can return garbage if propogation |
| 855 | * has happened |
| 856 | */ |
| 857 | if (isDef) |
| 858 | /* Set bit for the corresponding def */ |
| 859 | bitvSet(cpInfo.bitvClass, dfin, defNo); |
| 860 | |
| 861 | break; |
| 862 | } |
| 863 | |
| 864 | default: |
| 865 | break; |
| 866 | } |
| 867 | |
| 868 | return newFoam; |
| 869 | } |
| 870 | |
| 871 | |
| 872 | /**************************************************************************** |
| 873 | * |
| 874 | * :: cpProgInit and cpProgFini |
| 875 | * |
| 876 | ****************************************************************************/ |
| 877 | |
| 878 | localstatic void |
| 879 | cpProgInit(Foam prog) |
| 880 | { |
| 881 | int nLoc = foamDDeclArgc(prog->foamProg.locals)(((prog->foamProg.locals)->hdr.argc) - (1)); |
| 882 | int nPar = foamDDeclArgc(prog->foamProg.params)(((prog->foamProg.params)->hdr.argc) - (1)); |
| 883 | int i; |
| 884 | |
| 885 | assert(foamTag(prog) == FOAM_Prog)do { if (!(((prog)->hdr.tag) == FOAM_Prog)) _do_assert(("foamTag(prog) == FOAM_Prog" ),"of_cprop.c",885); } while (0); |
| 886 | |
| 887 | cpInfo.nLocals = nLoc; |
| 888 | cpInfo.nParams = nPar; |
| 889 | cpInfo.nCopies = 0; |
| 890 | cpInfo.nPropagated = 0; |
| 891 | cpInfo.varCopiesVect = (FoamList *) 0; |
| 892 | |
| 893 | if (nLoc + nPar == 0) |
| 894 | return; |
| 895 | |
| 896 | cpInfo.varCopiesVect = |
| 897 | (FoamList *) stoAlloc(OB_Other0, (nLoc + nPar) * sizeof(FoamList)); |
| 898 | |
| 899 | for (i = 0; i < nLoc + nPar; i++) |
| 900 | cpInfo.varCopiesVect[i] = listNil(Foam)((FoamList) 0); |
| 901 | |
| 902 | |
| 903 | } |
| 904 | |
| 905 | localstatic void |
| 906 | cpProgFini() |
| 907 | { |
| 908 | cpVarCopiesVectFree(); |
| 909 | return; |
| 910 | } |
| 911 | |
| 912 | /**************************************************************************** |
| 913 | * |
| 914 | * :: acFlog --- Collect assignments into BB |
| 915 | * |
| 916 | ****************************************************************************/ |
| 917 | |
| 918 | static BitvClass acBitClass; |
| 919 | static Bitv acMarkBits; |
| 920 | localstatic Bool acIsCandidate (BBlock); |
| 921 | localstatic BBlock acMergeWithSuccessor (FlowGraph, int); |
| 922 | localstatic void acFoldBlock(FlowGraph flog, int label); |
| 923 | |
| 924 | localstatic void |
| 925 | acFoldAssignments(FlowGraph flog) |
| 926 | { |
| 927 | Bitv candidates; |
| 928 | BBlock bb; |
| 929 | int i, sz; |
| 930 | sz = flogBlockC(flog)((flog)->blocks->pos); |
| 931 | acBitClass = bitvClassCreate(sz); |
| 932 | candidates = bitvNew(acBitClass); |
| 933 | acMarkBits = bitvNew(acBitClass); |
| 934 | bitvClearAll(acBitClass, candidates); |
| 935 | bitvClearAll(acBitClass, acMarkBits); |
| 936 | |
| 937 | for (i=0; i<sz; i++) { |
| 938 | bb = flogBlock(flog, i)bbufBlockFn((flog)->blocks,i); |
| 939 | if (!bb) continue; |
| 940 | if (acIsCandidate(bb)) |
| 941 | bitvSet(acBitClass, candidates, i); |
| 942 | } |
| 943 | |
| 944 | acFoldBlock(flog, flog->block0->label); |
| 945 | bitvClassDestroy(acBitClass); |
| 946 | } |
| 947 | |
| 948 | localstatic void |
| 949 | acFoldBlock(FlowGraph flog, int label) |
| 950 | { |
| 951 | BBlock bb = flogBlock(flog, label)bbufBlockFn((flog)->blocks,label); |
| 952 | int i; |
| 953 | |
| 954 | /* Depth first, post-order ensures that the |
| 955 | * target blocks should already be merged |
| 956 | * before the parent looks at them |
| 957 | */ |
| 958 | if (!bb) return; |
| 959 | if (label >= bitvClassSize(acBitClass)((acBitClass)->nbits)) |
| 960 | return; |
| 961 | if (bitvTest(acBitClass, acMarkBits, label)) |
| 962 | return; |
| 963 | |
| 964 | bitvSet(acBitClass, acMarkBits, label); |
| 965 | |
| 966 | for (i=0; i<bbExitC(bb)((bb)->exits->pos); i++) |
| 967 | acFoldBlock(flog, bbExit(bb, i)((bb)->exits->argv[i])->label); |
| 968 | |
| 969 | if (bbExitC(bb)((bb)->exits->pos) != 1) |
| 970 | return; |
| 971 | |
| 972 | if (acIsCandidate(bbExit(bb,int0)((bb)->exits->argv[((int) 0)]))) |
| 973 | bb = acMergeWithSuccessor(flog, label); |
Value stored to 'bb' is never read | |
| 974 | } |
| 975 | |
| 976 | localstatic Bool |
| 977 | acIsCandidate(BBlock bb) |
| 978 | { |
| 979 | Foam seq = bb->code; |
| 980 | int i; |
| 981 | |
| 982 | if (bbExitC(bb)((bb)->exits->pos) != 1) |
| 983 | return false((int) 0); |
| 984 | for (i=0; i<foamArgc(seq)((seq)->hdr.argc) - 1; i++) { |
| 985 | Foam foam = seq->foamSeq.argv[i]; |
| 986 | |
| 987 | if (!otIsDef(foam)(((foam)->hdr.tag) == FOAM_Set || ((foam)->hdr.tag) == FOAM_Def )) return false((int) 0); |
| 988 | if (!otIsLocalVar(foam->foamSet.lhs)(((foam->foamSet.lhs)->hdr.tag) == FOAM_Loc || ((foam-> foamSet.lhs)->hdr.tag) == FOAM_Par)) |
| 989 | return false((int) 0); |
| 990 | foam = foam->foamSet.rhs; |
| 991 | otDereferenceCast(foam)while (((foam)->hdr.tag) == FOAM_Cast) foam = foam->foamCast .expr;; |
| 992 | if (!otIsLocalVar(foam)(((foam)->hdr.tag) == FOAM_Loc || ((foam)->hdr.tag) == FOAM_Par )) |
| 993 | return false((int) 0); |
| 994 | } |
| 995 | |
| 996 | return true1; |
| 997 | } |
| 998 | |
| 999 | localstatic BBlock |
| 1000 | acMergeWithSuccessor(FlowGraph flog, int label) |
| 1001 | { |
| 1002 | BBlock thisBB, nextBB, newBB; |
| 1003 | Foam new; |
| 1004 | int i, j; |
| 1005 | |
| 1006 | thisBB = flogBlock(flog, label)bbufBlockFn((flog)->blocks,label); |
| 1007 | nextBB = bbExit(thisBB, int0)((thisBB)->exits->argv[((int) 0)]); |
| 1008 | if (thisBB == nextBB) |
| 1009 | return thisBB; |
| 1010 | |
| 1011 | new = foamNew(FOAM_Seq, foamArgc(thisBB->code)((thisBB->code)->hdr.argc) + foamArgc(nextBB->code)((nextBB->code)->hdr.argc) - 1); |
| 1012 | for (i=0; i<foamArgc(thisBB->code)((thisBB->code)->hdr.argc) - 1 ; i++) |
| 1013 | new->foamSeq.argv[i] = foamCopy(thisBB->code->foamSeq.argv[i]); |
| 1014 | for (j = 0; j<foamArgc(nextBB->code)((nextBB->code)->hdr.argc); i++, j++) |
| 1015 | new->foamSeq.argv[i] = foamCopy(nextBB->code->foamSeq.argv[j]); |
| 1016 | |
| 1017 | i = flogReserveLabel(flog)bbufReserve1((flog)->blocks); |
| 1018 | newBB = bbNew(new, i); |
| 1019 | flogSetBlock(flog, i, newBB)((flog)->fixedEntries = ((int) 0), bbufSetBlockFn((flog)-> blocks,i,newBB), (newBB)->graph = (flog)); |
| 1020 | bbufNeed(newBB->exits, 1); |
| 1021 | bbSetExitC(newBB, 1)((newBB)->exits->pos = (1)); |
| 1022 | bbSetExit(newBB, int0, bbExit(nextBB, int0))((newBB)->graph->fixedEntries = ((int) 0), (newBB)-> exits->argv[((int) 0)] = (((nextBB)->exits->argv[((int ) 0)]))); |
| 1023 | #if 0 |
| 1024 | fprintf(dbOut, "merging: %d with %d -> %d\n", label, nextBB->label, newBB->label); |
| 1025 | foamPrintDb(thisBB->code); |
| 1026 | foamPrintDb(nextBB->code); |
| 1027 | #endif |
| 1028 | if (flog->block0 == thisBB) { |
| 1029 | flog->block0 = newBB; |
| 1030 | newBB->isblock0 = true1; |
| 1031 | thisBB->isblock0 = false((int) 0); |
| 1032 | } |
| 1033 | for (i=0; i<flogBlockC(flog)((flog)->blocks->pos); i++) { |
| 1034 | BBlock bb = flogBlock(flog, i)bbufBlockFn((flog)->blocks,i); |
| 1035 | if (!bb) continue; |
| 1036 | for (j=0; j<bbExitC(bb)((bb)->exits->pos); j++) { |
| 1037 | if (bbExit(bb, j)((bb)->exits->argv[j]) == thisBB) |
| 1038 | bbSetExit(bb, j, newBB)((bb)->graph->fixedEntries = ((int) 0), (bb)->exits-> argv[j] = (newBB)); |
| 1039 | } |
| 1040 | } |
| 1041 | flogKillBlock(flog, label)((flog)->blocks->argv[label] = 0); |
| 1042 | |
| 1043 | return newBB; |
| 1044 | } |
| 1045 | |
| 1046 |