X-Git-Url: https://git.gag.com/?a=blobdiff_plain;f=src%2FSDCClrange.c;h=c4a5bcc2959a180b2a67d7b7e5499682aa854551;hb=eae1bd2f705a2c61e143c539f8c4d1e9c2b4efe6;hp=5dd9335667e699c361a5f23387cf6c7a866c7032;hpb=b09af35f2f1cde7649d3ac4a6f5d2af6d97895a0;p=fw%2Fsdcc diff --git a/src/SDCClrange.c b/src/SDCClrange.c index 5dd93356..c4a5bcc2 100644 --- a/src/SDCClrange.c +++ b/src/SDCClrange.c @@ -8,516 +8,929 @@ under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2, or (at your option) any later version. - + This program is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. - + You should have received a copy of the GNU General Public License along with this program; if not, write to the Free Software Foundation, 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. - + In other words, you are welcome to use, share and improve this program. You are forbidden to forbid anyone else to use, share and improve - what you give them. Help stamp out software-hoarding! + what you give them. Help stamp out software-hoarding! -------------------------------------------------------------------------*/ -#include -#include -#include "SDCCglobl.h" -#include "SDCCast.h" -#include "SDCCmem.h" -#include "SDCCy.h" -#include "SDCChasht.h" -#include "SDCCbitv.h" -#include "SDCCset.h" -#include "SDCCicode.h" -#include "SDCClabel.h" -#include "SDCCBBlock.h" -#include "SDCCloop.h" -#include "SDCCcse.h" -#include "SDCCcflow.h" -#include "SDCCdflow.h" -#include "SDCClrange.h" - -int iCodeSeq = 0 ; +#include "common.h" +#include "limits.h" + +int iCodeSeq = 0; hTab *liveRanges = NULL; hTab *iCodehTab = NULL; +hTab *iCodeSeqhTab = NULL; + +/* all symbols, for which the previous definition is searched + and warning is emitted if there's none. */ +#define IS_AUTOSYM(op) (IS_ITEMP(op) || \ + (IS_SYMOP(op) && IS_AUTO(op->operand.symOperand) && !IS_PARM(op))) + +/*-----------------------------------------------------------------*/ +/* hashiCodeKeys - add all iCodes to the hash table */ +/*-----------------------------------------------------------------*/ +void +hashiCodeKeys (eBBlock ** ebbs, int count) +{ + int i; + + for (i = 0; i < count; i++) + { + iCode *ic; + for (ic = ebbs[i]->sch; ic; ic = ic->next) + hTabAddItem (&iCodehTab, ic->key, ic); + } +} /*-----------------------------------------------------------------*/ /* sequenceiCode - creates a sequence number for the iCode & add */ /*-----------------------------------------------------------------*/ -void sequenceiCode (eBBlock **ebbs, int count) +static void +sequenceiCode (eBBlock ** ebbs, int count) { - int i; - - for (i = 0 ; i < count ; i++ ) { - - iCode *ic; - ebbs[i]->fSeq = iCodeSeq + 1; - for ( ic = ebbs[i]->sch ; ic ; ic= ic->next) { - ic->seq = ++iCodeSeq; - ic->depth = ebbs[i]->depth; - hTabAddItem(&iCodehTab,ic->key,ic); + int i; + + for (i = 0; i < count; i++) + { + + iCode *ic; + ebbs[i]->fSeq = iCodeSeq + 1; + for (ic = ebbs[i]->sch; ic; ic = ic->next) + { + ic->seq = ++iCodeSeq; + ic->depth = ebbs[i]->depth; + //hTabAddItem (&iCodehTab, ic->key, ic); + hTabAddItem (&iCodeSeqhTab, ic->seq, ic); } - ebbs[i]->lSeq = iCodeSeq ; + ebbs[i]->lSeq = iCodeSeq; } } /*-----------------------------------------------------------------*/ -/* markVisited - will set the visited flag for the given Block */ +/* setFromRange - sets the from range of a given operand */ /*-----------------------------------------------------------------*/ -DEFSETFUNC(markVisited) +#if 0 +static void +setFromRange (operand * op, int from) { - eBBlock *ebp = item; - - if (ebp->visited) - return 0; - ebp->visited = 1; - applyToSet(ebp->succList,markVisited); - return 0; + /* only for compiler defined temporaries */ + if (!IS_ITEMP (op)) + return; + + hTabAddItemIfNotP (&liveRanges, op->key, OP_SYMBOL (op)); + + if (op->isaddr) + OP_SYMBOL (op)->isptr = 1; + + if (!OP_LIVEFROM (op) || + OP_LIVEFROM (op) > from) + OP_LIVEFROM (op) = from; } +#endif /*-----------------------------------------------------------------*/ -/* isOpAlive - checks to see if the usage in this block is the */ -/* uses the same definitions as this one */ +/* setToRange - set the range to for an operand */ /*-----------------------------------------------------------------*/ -DEFSETFUNC(isOpAlive) +void +setToRange (operand * op, int to, bool check) { - eBBlock *ebp = item; - V_ARG(operand *,op); - V_ARG(eBBlock *,orig); - V_ARG(iCode *,ic); + /* only for compiler defined temps */ + if (!IS_ITEMP (op)) + return; + + OP_SYMBOL (op)->key = op->key; + hTabAddItemIfNotP (&liveRanges, op->key, OP_SYMBOL (op)); + + if (op->isaddr) + OP_SYMBOL (op)->isptr = 1; + + if (check) + if (!OP_LIVETO (op)) + OP_LIVETO (op) = to; + else; + else + OP_LIVETO (op) = to; +} - if (ebp->visited) - return 0; +/*-----------------------------------------------------------------*/ +/* setFromRange - sets the from range of a given operand */ +/*-----------------------------------------------------------------*/ +static void +setLiveFrom (symbol * sym, int from) +{ + if (!sym->liveFrom || sym->liveFrom > from) + sym->liveFrom = from; +} - ebp->visited = 1; - - /* if we have reached the originating block */ - /* or this block has some definiton for it */ - /* then check if it is used between start & */ - /* this point */ - if ( ebp == orig || - bitVectBitsInCommon(OP_DEFS(op),ebp->defSet)) - if (usedBetweenPoints (op,ebp->sch,ic)) - return 1; - else { - applyToSet(ebp->succList,markVisited); - return 0; - } - else - /* choosing this more expensive one since - killDeadCode will take away some definitions - but there is not way right now to take away - the usage information for the corresponding - usages, this will lead to longer live ranges */ - if (usedInRemaining(op,ebp->sch)) - return 1; +/*-----------------------------------------------------------------*/ +/* setToRange - set the range to for an operand */ +/*-----------------------------------------------------------------*/ +static void +setLiveTo (symbol * sym, int to) +{ + if (!sym->liveTo || sym->liveTo < to) + sym->liveTo = to; +} + +/*-----------------------------------------------------------------*/ +/* markLiveRanges - for each operand mark the liveFrom & liveTo */ +/*-----------------------------------------------------------------*/ +static void +markLiveRanges (eBBlock ** ebbs, int count) +{ + int i, key; + symbol *sym; + for (i = 0; i < count; i++) + { + iCode *ic; + + for (ic = ebbs[i]->sch; ic; ic = ic->next) + { + if (ic->op == CALL || ic->op == PCALL) + if (bitVectIsZero (OP_SYMBOL (IC_RESULT (ic))->uses)) + bitVectUnSetBit (ebbs[i]->defSet, ic->key); + + /* for all iTemps alive at this iCode */ + for (key = 1; key < ic->rlive->size; key++) + { + if (!bitVectBitValue(ic->rlive, key)) + continue; + + sym = hTabItemWithKey(liveRanges, key); + setLiveTo(sym, ic->seq); + setLiveFrom(sym, ic->seq); + } - return (applyToSet(ebp->succList,isOpAlive,op,orig,ic)); + } + } } /*-----------------------------------------------------------------*/ -/* isLastUse - return TRUE if no usage of this operand after this */ +/* markAlive - marks the operand as alive between sic and eic */ /*-----------------------------------------------------------------*/ -int isLastUse (operand *op, eBBlock *ebp, iCode *ic, - eBBlock **ebbs, int count) +static void +markAlive (iCode * sic, iCode * eic, int key) { - int i; - - /* if this is used in the remaining */ - if (usedInRemaining(op,ic)) - return 0; - - /* if not then check any of the successor blocks use it */ - for (i = 0 ; i < count ; ebbs[i++]->visited = 0); - if (applyToSet(ebp->succList,isOpAlive,op,ebp,ic)) - return 0; - - /* this is the last use */ - return 1; + iCode *dic; + + for (dic = sic; dic != eic->next; dic = dic->next) + { + dic->rlive = bitVectSetBit (dic->rlive, key); + } } /*-----------------------------------------------------------------*/ -/* unionDefsUsed - unions the defsUsed in a block */ +/* findNextUseSym - finds the next use of the symbol and marks it */ +/* alive in between */ /*-----------------------------------------------------------------*/ -DEFSETFUNC(unionDefsUsed) +static int +findNextUseSym (eBBlock *ebp, iCode *ic, symbol * sym) { - eBBlock *ebp = item; - V_ARG(bitVect **,bvp); + int retval = 0; + iCode *uic; + eBBlock *succ; - if (ebp->visited) - return 0; + hTabAddItemIfNotP (&liveRanges, sym->key, sym); - ebp->visited = 1; + if (!ic) + goto check_successors; + + /* if we check a complete block and the symbol */ + /* is alive at the beginning of the block */ + /* and not defined in the first instructions */ + /* then a next use exists (return 1) */ + if ((ic == ebp->sch) && bitVectBitValue(ic->rlive, sym->key)) + { + /* check if the first instruction is a def of this op */ + if (ic->op == JUMPTABLE || ic->op == IFX || SKIP_IC2(ic)) + return 1; - *bvp = bitVectUnion(*bvp, ebp->usesDefs); - applyToSet(ebp->succList,unionDefsUsed,bvp); + if (IS_ITEMP(IC_RESULT(ic))) + if (IC_RESULT(ic)->key == sym->key) + return 0; + + return 1; + } + + if (ebp->visited) return 0; + + if (ic == ebp->sch) + ebp->visited = 1; + + /* for all remaining instructions in current block */ + for (uic = ic; uic; uic = uic->next) + { + + if (SKIP_IC2(uic)) + continue; + + if (uic->op == JUMPTABLE) + { + if (IS_ITEMP(IC_JTCOND(uic)) && IC_JTCOND(uic)->key == sym->key) + { + markAlive(ic, uic, sym->key); + return 1; + } + continue; + } + + if (uic->op == IFX) + { + if (IS_ITEMP(IC_COND(uic)) && IC_COND(uic)->key == sym->key) + { + markAlive(ic, uic, sym->key); + return 1; + } + continue; + } + + if (IS_ITEMP (IC_LEFT (uic))) + if (IC_LEFT (uic)->key == sym->key) + { + markAlive(ic, uic, sym->key); + return 1; + } + + if (IS_ITEMP (IC_RIGHT (uic))) + if (IC_RIGHT (uic)->key == sym->key) + { + markAlive (ic, uic, sym->key); + return 1; + } + + if (IS_ITEMP (IC_RESULT (uic))) + if (IC_RESULT (uic)->key == sym->key) + { + if (POINTER_SET (uic)) + { + markAlive (ic, uic, sym->key); + return 1; + } + else + return 0; + } + + } + + /* check all successors */ +check_successors: + + succ = setFirstItem (ebp->succList); + for (; succ; succ = setNextItem (ebp->succList)) + { + retval += findNextUseSym (succ, succ->sch, sym); + } + + if (retval) + { + if (ic) markAlive (ic, ebp->ech, sym->key); + return 1; + } + + return 0; } /*-----------------------------------------------------------------*/ -/* setFromRange - sets the from range of a given operand */ +/* findNextUse - finds the next use of the operand and marks it */ +/* alive in between */ /*-----------------------------------------------------------------*/ -void setFromRange (operand *op, int from) +static int +findNextUse (eBBlock *ebp, iCode *ic, operand *op) { - /* only for compiler defined temporaries */ - if (!IS_ITEMP(op)) - return ; - - hTabAddItemIfNotP (&liveRanges,op->key,OP_SYMBOL(op)); + if (op->isaddr) + OP_SYMBOL (op)->isptr = 1; - if (op->isaddr) - OP_SYMBOL(op)->isptr = 1; + OP_SYMBOL (op)->key = op->key; - if (!OP_LIVEFROM(op) || - OP_LIVEFROM(op) > from) - OP_LIVEFROM(op) = from; + return findNextUseSym (ebp, ic, OP_SYMBOL(op)); } /*-----------------------------------------------------------------*/ -/* setToRange - set the range to for an operand */ +/* unvisitBlocks - clears visited in all blocks */ /*-----------------------------------------------------------------*/ -void setToRange (operand *op,int to, bool check) -{ - /* only for compiler defined temps */ - if (!IS_ITEMP(op)) - return ; - - OP_SYMBOL(op)->key = op->key; - hTabAddItemIfNotP (&liveRanges,op->key,OP_SYMBOL(op)); - - if (op->isaddr) - OP_SYMBOL(op)->isptr = 1; - - if (check) - if (!OP_LIVETO(op)) - OP_LIVETO(op) = to; - else ; - else - OP_LIVETO(op) = to; +static void +unvisitBlocks (eBBlock ** ebbs, int count) +{ + int i; + + for (i = 0; i < count; i++) + ebbs[i]->visited = 0; } +/*------------------------------------------------------------------*/ +/* markWholeLoop - mark the symbol 'key' alive in all blocks */ +/* included by the outermost loop */ +/*------------------------------------------------------------------*/ +static void +markWholeLoop (eBBlock *ebp, int key) +{ + eBBlock *ebpi; -/*-----------------------------------------------------------------*/ -/* operandLUse - check and set the last use for a given operand */ -/*-----------------------------------------------------------------*/ -operand *operandLUse (operand *op, eBBlock **ebbs, - int count, iCode *ic, eBBlock *ebp) -{ - setFromRange(op,ic->seq); - if (ic->depth) - OP_SYMBOL(op)->used += (((unsigned int)1 << ic->depth) + 1); - else - OP_SYMBOL(op)->used += 1; - - if (isLastUse(op,ebp,ic->next,ebbs,count) || - (OP_LIVETO(op) && OP_LIVETO(op) < ic->seq)) { - int torange = ic->seq; - /* if this is the last use then if this block belongs - to a loop & some definition comes into the loop - then extend the live range to the end of the loop */ - if (ebp->partOfLoop && - hasIncomingDefs(ebp->partOfLoop,op)) { - torange = findLoopEndSeq(ebp->partOfLoop); - } - op = operandFromOperand(op); - setToRange(op,torange,FALSE); - } - ic->uses = bitVectSetBit(ic->uses,op->key); - + /* avoid endless loops */ + ebp->visited = 1; + + /* recurse through all predecessors */ + for (ebpi = setFirstItem (ebp->predList); + ebpi; + ebpi = setNextItem (ebp->predList)) { - link *type = operandType(op); - link *etype = getSpec(type); - - /* good place to check if unintialised */ - if ((IS_TRUE_SYMOP(op) || OP_SYMBOL(op)->isreqv) && - OP_SYMBOL(op)->islocal && - !IS_AGGREGATE(type) && - !IS_FUNC(type) && - ic->op != ADDRESS_OF && - !IS_STATIC(etype) ) { - -/* if (OP_SYMBOL(op)->isreqv && !OP_SYMBOL(op)->_isparm){ */ - -/* if (SPIL_LOC(op) && */ -/* bitVectIsZero(SPIL_LOC(op)->defs)) { */ -/* OP_SYMBOL(op)->isspilt = 1; */ -/* werror(W_LOCAL_NOINIT, */ -/* SPIL_LOC(op)->name, */ -/* ic->filename,ic->lineno); */ -/* } */ -/* } else { */ - - if (bitVectIsZero(op->usesDefs)) { - OP_SYMBOL(op)->isspilt = 1; - werror(W_LOCAL_NOINIT, - OP_SYMBOL(op)->name, - ic->filename,ic->lineno); - } -/* } */ - } + if (ebpi->visited) + continue; + /* is the predecessor still in the loop? */ + if (ebpi->depth == 0) + continue; + markWholeLoop (ebpi, key); } - return op; + + /* recurse through all successors */ + for (ebpi = setFirstItem (ebp->succList); + ebpi; + ebpi = setNextItem (ebp->succList)) + { + if (ebpi->visited) + continue; + if (ebpi->depth == 0) + continue; + markWholeLoop (ebpi, key); + } + + markAlive (ebp->sch, ebp->ech, key); } -/*-----------------------------------------------------------------*/ -/* compLastUse - computes the last usage with certainty */ -/*-----------------------------------------------------------------*/ -void compLastUse () +/*------------------------------------------------------------------*/ +/* findPrevUseSym - search for a previous definition of a symbol in */ +/* - the previous icodes */ +/* - all branches of predecessors */ +/*------------------------------------------------------------------*/ +static bool +findPrevUseSym (eBBlock *ebp, iCode *ic, symbol * sym) { - symbol *sym; - int key; - /* the strategy here is to look for live ranges that are not - induction variables, and find out the usage icode with the - highest sequence number then set the to range to that icode - sequence */ - /* once fully tested we can use only this routine to mark the - to range that will reduce a lot of computations in the - markLiveRanges routine */ - for (sym = hTabFirstItem(liveRanges,&key) ; sym; - sym = hTabNextItem(liveRanges,&key)) { - - int i ; - int maxKey = 0 ; - - if (sym->isind) - continue ; - - if (!sym->uses) - continue ; - - /* go thru all the usages of this live range and find out - the maximum sequence number of the icode that used it */ - for (i = 0 ; i < sym->uses->size ; i++ ) { - iCode *uic ; - - if (!bitVectBitValue(sym->uses,i)) - continue ; - - if ((uic = hTabItemWithKey(iCodehTab,i))) - maxKey = ( uic->seq > maxKey ? uic->seq : maxKey ); - } + eBBlock * pred; + iCode * uic; + + if (ebp->visited) + { + /* already visited: this branch must have been succesfull, */ + /* because otherwise the search would have been aborted. */ + return TRUE; + } + ebp->visited = 1; + + /* search backward in the current block */ + for (uic = ic; uic; uic = uic->prev) + { + if (!POINTER_SET (uic) && IS_AUTOSYM (IC_RESULT (uic))) + { + if (IC_RESULT (uic)->key == sym->key) + { + /* Ok, found a definition */ + return TRUE; + } + } + /* address taken from symbol? */ + if (uic->op == ADDRESS_OF && IS_AUTOSYM (IC_LEFT (uic))) + { + if (IC_LEFT (uic)->key == sym->key) + { + /* Ok, found a definition */ + return TRUE; + } + } + } - /* got it */ - if (maxKey) - sym->liveTo = maxKey; + /* There's no definition in this bblock, */ + /* let's have a look at all predecessors. */ + pred = setFirstItem (ebp->predList); + if (!pred) + { + /* no more predecessors and nothing found yet :-( */ + return FALSE; + } + for (; pred; pred = setNextItem (ebp->predList)) + { + /* recurse into all predecessors */ + if (!findPrevUseSym (pred, pred->ech, sym)) + { + /* found nothing: abort */ + return FALSE; + } + } + + /* Success! Went through all branches with no abort: */ + /* all branches end with a definition */ + return TRUE; +} + +/*------------------------------------------------------------------*/ +/* findPrevUse - search for a previous definition of an operand */ +/* If there's no definition let's: */ +/* - emit a warning */ +/* - fix the life range, if the symbol is used in */ +/* a loop */ +/*------------------------------------------------------------------*/ +static void +findPrevUse (eBBlock *ebp, iCode *ic, operand *op, + eBBlock ** ebbs, int count, + bool emitWarnings) +{ + unvisitBlocks (ebbs, count); + + if (op->isaddr) + OP_SYMBOL (op)->isptr = 1; + OP_SYMBOL (op)->key = op->key; + + /* There must be a definition in each branch of predecessors */ + if (!findPrevUseSym (ebp, ic->prev, OP_SYMBOL(op))) + { + /* computeLiveRanges() is called twice */ + if (emitWarnings) + { + if (IS_ITEMP (op)) + { + if (OP_SYMBOL (op)->prereqv) + { + werrorfl (ic->filename, ic->lineno, W_LOCAL_NOINIT, + OP_SYMBOL (op)->prereqv->name); + OP_SYMBOL (op)->prereqv->reqv = NULL; + OP_SYMBOL (op)->prereqv->allocreq = 1; + } + } + else + { + werrorfl (ic->filename, ic->lineno, W_LOCAL_NOINIT, + OP_SYMBOL (op)->name); + } + } + /* is this block part of a loop? */ + if (IS_ITEMP (op) && ebp->depth != 0) + { + /* extend the life range to the outermost loop */ + unvisitBlocks(ebbs, count); + markWholeLoop (ebp, op->key); + } } } /*-----------------------------------------------------------------*/ -/* killAllAlive - mark all the definitions living with this seq */ +/* incUsed - increment a symbol's usage count */ /*-----------------------------------------------------------------*/ -void killAllAlive (int seq) +static void +incUsed (iCode *ic, operand *op) { - symbol *sym; - int k; - - for (sym = hTabFirstItem(liveRanges,&k); sym; - sym = hTabNextItem(liveRanges,&k)) - if (!sym->liveTo || (sym->liveTo < sym->liveFrom)) - sym->liveTo = seq; + if (ic->depth) + OP_SYMBOL (op)->used += (((unsigned int) 1 << ic->depth) + 1); + else + OP_SYMBOL (op)->used += 1; } + /*-----------------------------------------------------------------*/ -/* defUsedAfterLoop - all definitions & usages before sequence num */ +/* rliveClear - clears the rlive bitVectors */ /*-----------------------------------------------------------------*/ -bool defUsedAfterLoop (operand *op, int seq) +static void +rliveClear (eBBlock ** ebbs, int count) { - int i; - iCode *ic; - - /* check for the usages first */ - if (OP_SYMBOL(op)->uses && !bitVectIsZero(OP_SYMBOL(op)->uses)) { - for (i = 0 ; i < OP_SYMBOL(op)->uses->size ; i++ ) { - - if (bitVectBitValue( OP_SYMBOL(op)->uses,i) && /* usage found */ - (ic = hTabItemWithKey(iCodehTab,i)) && /* "" */ - ic->seq > seq ) /* & is after the seq */ - return TRUE ; + int i; + + /* for all blocks do */ + for (i = 0; i < count; i++) + { + iCode *ic; + + /* for all instructions in this block do */ + for (ic = ebbs[i]->sch; ic; ic = ic->next) + { + freeBitVect (ic->rlive); + ic->rlive = NULL; } } - - return FALSE; } /*-----------------------------------------------------------------*/ -/* markLiveRanges - for each operand mark the liveFrom & liveTo */ +/* rlivePoint - for each point compute the ranges that are alive */ +/* The live range is only stored for ITEMPs; the same code is used */ +/* to find use of unitialized AUTOSYMs (an ITEMP is an AUTOSYM). */ /*-----------------------------------------------------------------*/ -void markLiveRanges (eBBlock *ebp, eBBlock **ebbs, int count) +static void +rlivePoint (eBBlock ** ebbs, int count, bool emitWarnings) { - iCode *ic; - bitVect *defsUsed = NULL; - bitVect *defsNotUsed = NULL; - int i; - /* for all the instructions */ - for (ic = ebp->sch ; ic ; ic = ic->next ) { - - if (ic->op == CALL || ic->op == PCALL) { - setFromRange(IC_RESULT(ic),ic->seq); - /* if the result has no usage then - mark this as the end of its life too - and take it away from the defs for the block*/ - if (bitVectIsZero(OP_SYMBOL(IC_RESULT(ic))->uses)) { - setToRange(IC_RESULT(ic),ic->seq,FALSE); - bitVectUnSetBit(ebp->defSet,ic->key); + int i, key; + eBBlock *succ; + bitVect *alive; + + /* for all blocks do */ + for (i = 0; i < count; i++) + { + iCode *ic; + + /* for all instructions in this block do */ + for (ic = ebbs[i]->sch; ic; ic = ic->next) + { + + if (!ic->rlive) + ic->rlive = newBitVect (operandKey); + + if (SKIP_IC2(ic)) + continue; + + if (ic->op == JUMPTABLE && IS_SYMOP(IC_JTCOND(ic))) + { + incUsed (ic, IC_JTCOND(ic)); + + if (!IS_AUTOSYM(IC_JTCOND(ic))) + continue; + + findPrevUse (ebbs[i], ic, IC_JTCOND(ic), ebbs, count, emitWarnings); + if (IS_ITEMP(IC_JTCOND(ic))) + { + unvisitBlocks(ebbs, count); + ic->rlive = bitVectSetBit (ic->rlive, IC_JTCOND(ic)->key); + findNextUse (ebbs[i], ic->next, IC_JTCOND(ic)); + } + + continue; + } + + if (ic->op == IFX && IS_SYMOP(IC_COND(ic))) + { + incUsed (ic, IC_COND(ic)); + + if (!IS_AUTOSYM(IC_COND(ic))) + continue; + + findPrevUse (ebbs[i], ic, IC_COND(ic), ebbs, count, emitWarnings); + if (IS_ITEMP(IC_COND(ic))) + { + unvisitBlocks (ebbs, count); + ic->rlive = bitVectSetBit (ic->rlive, IC_COND(ic)->key); + findNextUse (ebbs[i], ic->next, IC_COND(ic)); + } + + continue; + } + + if (IS_SYMOP(IC_LEFT(ic))) + { + incUsed (ic, IC_LEFT(ic)); + if (IS_AUTOSYM(IC_LEFT(ic)) && + ic->op != ADDRESS_OF) + { + findPrevUse (ebbs[i], ic, IC_LEFT(ic), ebbs, count, emitWarnings); + if (IS_ITEMP(IC_LEFT(ic))) + { + unvisitBlocks(ebbs, count); + ic->rlive = bitVectSetBit (ic->rlive, IC_LEFT(ic)->key); + findNextUse (ebbs[i], ic->next, IC_LEFT(ic)); + + /* if this is a send extend the LR to the call */ + if (ic->op == SEND) + { + iCode *lic; + for (lic = ic; lic; lic = lic->next) + { + if (lic->op == CALL || lic->op == PCALL) + { + markAlive (ic, lic->prev, IC_LEFT (ic)->key); + break; + } + } + } + } + } + } + + if (IS_SYMOP(IC_RIGHT(ic))) + { + incUsed (ic, IC_RIGHT(ic)); + if (IS_AUTOSYM(IC_RIGHT(ic))) + { + findPrevUse (ebbs[i], ic, IC_RIGHT(ic), ebbs, count, emitWarnings); + if (IS_ITEMP(IC_RIGHT(ic))) + { + unvisitBlocks(ebbs, count); + ic->rlive = bitVectSetBit (ic->rlive, IC_RIGHT(ic)->key); + findNextUse (ebbs[i], ic->next, IC_RIGHT(ic)); + } + } + } + + if (POINTER_SET(ic) && IS_SYMOP(IC_RESULT(ic))) + incUsed (ic, IC_RESULT(ic)); + + if (IS_AUTOSYM(IC_RESULT(ic))) + { + if (POINTER_SET(ic)) + { + findPrevUse (ebbs[i], ic, IC_RESULT(ic), ebbs, count, emitWarnings); + } + if (IS_ITEMP(IC_RESULT(ic))) + { + unvisitBlocks(ebbs, count); + ic->rlive = bitVectSetBit (ic->rlive, IC_RESULT(ic)->key); + findNextUse (ebbs[i], ic->next, IC_RESULT(ic)); + } } + + if (!POINTER_SET(ic) && IC_RESULT(ic)) + ic->defKey = IC_RESULT(ic)->key; + } - if (SKIP_IC2(ic)) - continue ; + /* check all symbols that are alive in the last instruction */ + /* but are not alive in all successors */ - /* take care of the special icodes first */ - if (ic->op == JUMPTABLE && IS_SYMOP(IC_JTCOND(ic))) { - operandLUse (IC_JTCOND(ic),ebbs,count,ic,ebp); + succ = setFirstItem (ebbs[i]->succList); + if (!succ) + continue; + + alive = succ->sch->rlive; + while ((succ = setNextItem (ebbs[i]->succList))) + { + if (succ->sch) + alive = bitVectIntersect (alive, succ->sch->rlive); + } + + if (ebbs[i]->ech) + alive = bitVectCplAnd ( bitVectCopy (ebbs[i]->ech->rlive), alive); + + if(!alive) + continue; + for (key = 1; key < alive->size; key++) + { + if (!bitVectBitValue (alive, key)) continue; + + unvisitBlocks(ebbs, count); + findNextUseSym (ebbs[i], NULL, hTabItemWithKey (liveRanges, key)); } - - if (ic->op == IFX && IS_SYMOP(IC_COND(ic))) { - operandLUse (IC_COND(ic),ebbs,count,ic,ebp); - continue ; - } - - if (IS_SYMOP(IC_LEFT(ic))) - operandLUse (IC_LEFT(ic),ebbs,count,ic,ebp); - - if (IS_SYMOP(IC_RIGHT(ic))) - operandLUse (IC_RIGHT(ic),ebbs,count,ic,ebp); - - if (POINTER_SET(ic)) - operandLUse(IC_RESULT(ic),ebbs,count,ic,ebp); - else - if (IC_RESULT(ic)) - ic->defKey = IC_RESULT(ic)->key ; + } +} +/*-----------------------------------------------------------------*/ +/* computeClash - find out which live ranges collide with others */ +/*-----------------------------------------------------------------*/ +static void +computeClash (eBBlock ** ebbs, int count) +{ + int i; - /* for all the definitions in the block */ - /* compute and set the live from */ - if ( ebp->defSet && ! bitVectIsZero(ebp->defSet)) { - for ( i = 0 ; i < ebp->defSet->size ; i++ ) { - iCode *dic; - - if (bitVectBitValue(ebp->defSet,i) && - (dic = hTabItemWithKey(iCodehTab,i))) { - - /* if the definition has a from & it is greater */ - /* than the defininng iCode->seq then change it */ - setFromRange(IC_RESULT(dic),dic->seq); - } - } - } + /* for all blocks do */ + for (i = 0; i < count; i++) + { + iCode *ic; + + /* for every iCode do */ + for (ic = ebbs[i]->sch; ic; ic = ic->next) + { + symbol *sym1, *sym2; + int key1, key2; + + /* for all iTemps alive at this iCode */ + for (key1 = 1; key1 < ic->rlive->size; key1++) + { + if (!bitVectBitValue(ic->rlive, key1)) + continue; + + sym1 = hTabItemWithKey(liveRanges, key1); - /* special case for lastBlock in a loop: here we - mark the end of all the induction variables for the - loop */ - if (ebp->isLastInLoop && !bitVectIsZero(ebp->linds)) { - for ( i = 0 ; i <= ebp->linds->size ; i++ ) { - iCode *dic; - - if (bitVectBitValue(ebp->linds,i) && - (dic = hTabItemWithKey(iCodehTab,i))) { - - /* if this is a register equvalent make sure - it is not defined or used anywhere after the loop */ - if (OP_SYMBOL(IC_RESULT(dic))->isreqv && - defUsedAfterLoop(IC_RESULT(dic), ebp->lSeq)) + if (!sym1->isitmp) + continue; + + /* for all other iTemps alive at this iCode */ + for (key2 = key1+1; key2 < ic->rlive->size; key2++) + { + if (!bitVectBitValue(ic->rlive, key2)) continue; - setToRange(IC_RESULT(dic),( ebp->lSeq ),FALSE); - } - } - } + sym2 = hTabItemWithKey(liveRanges, key2); - /* for defnitions coming into the block if they */ - /* not used by itself & any of its successors */ - /* they are dead */ - /* first union the definitions used in all successors - and itself */ - for (i = 0; i < count ; ebbs[i++]->visited = 0); - applyToSet(ebp->succList,unionDefsUsed,&defsUsed); - defsUsed = bitVectUnion(defsUsed,ebp->usesDefs); - - /* now subract the result of these unions from */ - /* the incoming definitions this will give the */ - /* definitions that are never used in the future */ - defsNotUsed = bitVectCplAnd(bitVectCopy(ebp->inDefs), - defsUsed); - - /* mark the end of the defintions */ - if ( !bitVectIsZero(defsNotUsed) && ebp->sch ) { - for ( i = 0 ; i < defsNotUsed->size; i++ ) { - iCode *dic; - - if (bitVectBitValue(defsNotUsed,i) && - (dic = hTabItemWithKey(iCodehTab,i))) { - - setToRange(IC_RESULT(dic),( ebp->fSeq - 1),TRUE); + if (!sym2->isitmp) + continue; + + /* if the result and left or right is an iTemp */ + /* than possibly the iTemps do not clash */ + if ((ic->op != JUMPTABLE) && (ic->op != IFX) && + IS_ITEMP(IC_RESULT(ic)) && + (IS_ITEMP(IC_LEFT(ic)) || IS_ITEMP(IC_RIGHT(ic)))) + { + if (OP_SYMBOL(IC_RESULT(ic))->key == key1 + && sym1->liveFrom == ic->seq + && sym2->liveTo == ic->seq) + { + if (IS_SYMOP(IC_LEFT(ic))) + if (OP_SYMBOL(IC_LEFT(ic))->key == key2) + continue; + if (IS_SYMOP(IC_RIGHT(ic))) + if (OP_SYMBOL(IC_RIGHT(ic))->key == key2) + continue; + } + + if (OP_SYMBOL(IC_RESULT(ic))->key == key2 + && sym2->liveFrom == ic->seq + && sym1->liveTo == ic->seq) + { + if (IS_SYMOP(IC_LEFT(ic))) + if (OP_SYMBOL(IC_LEFT(ic))->key == key1) + continue; + if (IS_SYMOP(IC_RIGHT(ic))) + if (OP_SYMBOL(IC_RIGHT(ic))->key == key1) + continue; + } + } + + /* the iTemps do clash. set the bits in clashes */ + sym1->clashes = bitVectSetBit (sym1->clashes, key2); + sym2->clashes = bitVectSetBit (sym2->clashes, key1); + + /* check if they share the same spill location */ + /* what is this good for? */ + if (SYM_SPIL_LOC(sym1) && SYM_SPIL_LOC(sym2) && + SYM_SPIL_LOC(sym1) == SYM_SPIL_LOC(sym2)) + { + if (sym1->reqv && !sym2->reqv) SYM_SPIL_LOC(sym2)=NULL; + else if (sym2->reqv && !sym1->reqv) SYM_SPIL_LOC(sym1)=NULL; + else if (sym1->used > sym2->used) SYM_SPIL_LOC(sym2)=NULL; + else SYM_SPIL_LOC(sym1)=NULL; + } + } } } } +} + +/*-----------------------------------------------------------------*/ +/* allDefsOutOfRange - all definitions are out of a range */ +/*-----------------------------------------------------------------*/ +bool +allDefsOutOfRange (bitVect * defs, int fseq, int toseq) +{ + int i; + + if (!defs) + return TRUE; + + for (i = 0; i < defs->size; i++) + { + iCode *ic; + if (bitVectBitValue (defs, i) && + (ic = hTabItemWithKey (iCodehTab, i)) && + (ic->seq >= fseq && ic->seq <= toseq)) + return FALSE; - /* if we reach a lock with noPath to it then kill all - the live ranges alive at this point */ -/* if (ebp->noPath || ebp->entryLabel == returnLabel) */ - if (ebp->entryLabel == returnLabel) - killAllAlive(ebp->fSeq); + } + + return TRUE; } /*-----------------------------------------------------------------*/ -/* rlivePoint - for each point compute the ranges that are alive */ +/* notUsedInBlock - not used in this block */ /*-----------------------------------------------------------------*/ -void rlivePoint (eBBlock **ebbs, int count) +int +notUsedInBlock (symbol * sym, eBBlock * ebp, iCode *ic) { - int i; - - /* for all blocks do */ - for ( i = 0 ; i < count ; i++ ) { - iCode *ic; - - /* for all instruction in the block do */ - for ( ic = ebbs[i]->sch ; ic ; ic = ic->next ) { - symbol *lrange; - int k; - - ic->rlive = newBitVect(operandKey); - /* for all symbols in the liverange table */ - for ( lrange = hTabFirstItem(liveRanges,&k); lrange; - lrange = hTabNextItem(liveRanges,&k)) { - - if (lrange->liveFrom <= ic->seq && - lrange->liveTo >= ic->seq ) - ic->rlive = bitVectSetBit(ic->rlive,lrange->key); - } - } - } + return (!bitVectBitsInCommon (sym->defs, ebp->usesDefs) && + allDefsOutOfRange (sym->defs, ebp->fSeq, ebp->lSeq) && + allDefsOutOfRange (sym->uses, ebp->fSeq, ebp->lSeq)); } +/*-----------------------------------------------------------------*/ +/* adjustIChain - correct the sch and ech pointers */ +/*-----------------------------------------------------------------*/ +static void +adjustIChain (eBBlock ** ebbs, int count) +{ + int i; + + for (i = 0; i < count; i++) + { + iCode *ic; + + if (ebbs[i]->noPath) + continue; + + ic = ebbs[i]->sch; + + /* is there any code for this eBBlock? (e.g. ROM assignment) */ + if(!ic)continue; + + while (ic->prev) + ic = ic->prev; + ebbs[i]->sch = ic; + + ic = ebbs[i]->ech; + while (ic->next) + ic = ic->next; + ebbs[i]->ech = ic; + } +} /*-----------------------------------------------------------------*/ /* computeLiveRanges - computes the live ranges for variables */ /*-----------------------------------------------------------------*/ -void computeLiveRanges (eBBlock **ebbs, int count ) +void +computeLiveRanges (eBBlock ** ebbs, int count, bool emitWarnings) +{ + /* first look through all blocks and adjust the + sch and ech pointers */ + adjustIChain (ebbs, count); + + /* sequence the code the live ranges are computed + in terms of this sequence additionally the + routine will also create a hashtable of instructions */ + iCodeSeq = 0; + setToNull ((void *) &iCodehTab); + iCodehTab = newHashTable (iCodeKey); + hashiCodeKeys (ebbs, count); + setToNull ((void *) &iCodeSeqhTab); + iCodeSeqhTab = newHashTable (iCodeKey); + sequenceiCode (ebbs, count); + + /* mark the ranges live for each point */ + setToNull ((void *) &liveRanges); + rlivePoint (ebbs, count, emitWarnings); + + /* mark the from & to live ranges for variables used */ + markLiveRanges (ebbs, count); + + /* compute which overlaps with what */ + computeClash(ebbs, count); +} + +/*-----------------------------------------------------------------*/ +/* recomputeLiveRanges - recomputes the live ranges for variables */ +/*-----------------------------------------------------------------*/ +void +recomputeLiveRanges (eBBlock ** ebbs, int count) { - int i = 0 ; - /* sequence the code the live ranges are computed - in terms of this sequence additionally the - routine will also create a hashtable of instructions */ - iCodeSeq = 0 ; - setToNull((void **)&iCodehTab); - iCodehTab = newHashTable (iCodeKey); - sequenceiCode(ebbs,count); - - /* call routine to mark the from & to live ranges for - variables used */ - setToNull((void **)&liveRanges); - for ( i = 0 ; i < count; i++ ) - markLiveRanges (ebbs[i],ebbs,count); - -/* compLastUse(); */ - /* mark the ranges live for each point */ - rlivePoint (ebbs,count); + symbol * sym; + int key; + + /* clear all rlive bitVectors */ + rliveClear (ebbs, count); + + sym = hTabFirstItem (liveRanges, &key); + if (sym) + { + do { + sym->used = 0; + sym->liveFrom = 0; + sym->liveTo = 0; + freeBitVect (sym->clashes); + sym->clashes = NULL; + } while ( (sym = hTabNextItem (liveRanges, &key))); + } + + /* do the LR computation again */ + computeLiveRanges (ebbs, count, FALSE); +} + +/*-----------------------------------------------------------------*/ +/* dump icode->rlive in all blocks */ +/*-----------------------------------------------------------------*/ +#if 0 +void +dumpIcRlive (eBBlock ** ebbs, int count) +{ + int i, j; + iCode *ic; + + /* for all blocks do */ + for (i = 0; i < count; i++) + { + printf ("bb %d %s alive symbols:\n", i, ebbs[i]->entryLabel->name); + /* for all instructions in this block do */ + for (ic = ebbs[i]->sch; ic; ic = ic->next) + { + printf ("\tic->key %d\n", ic->key); + + if (!ic->rlive) + continue; + /* for all live Ranges alive at this point */ + for (j = 1; j < ic->rlive->size; j++) + { + symbol *sym; + + if (!bitVectBitValue (ic->rlive, j)) + continue; + + /* find the live range we are interested in */ + if ((sym = hTabItemWithKey (liveRanges, j))) + printf ("\t\tsym->key %2d: %s\n", sym->key, sym->rname[0] ? sym->rname : sym->name); + } + } + } } +#endif