/*-----------------------------------------------------------------*/
/* newInduction - creates a new induction variable */
/*-----------------------------------------------------------------*/
-induction *
+static induction *
newInduction (operand * sym, unsigned int op,
long constVal, iCode * ic, operand * asym)
{
induction *ip;
- ip = Safe_calloc (1, sizeof (induction));
+ ip = Safe_alloc ( sizeof (induction));
ip->sym = sym;
ip->asym = asym;
ip->op = op;
ip->cval = constVal;
ip->ic = ic;
- updateSpillLocation(ic,1);
+//updateSpillLocation(ic,1);
return ip;
}
/*-----------------------------------------------------------------*/
/* newRegion - allocate & returns a loop structure */
/*-----------------------------------------------------------------*/
-region *
+static region *
newRegion ()
{
region *lp;
- lp = Safe_calloc (1, sizeof (region));
+ lp = Safe_alloc ( sizeof (region));
return lp;
}
+#if 0
/*-----------------------------------------------------------------*/
/* pinduction - prints induction */
/*-----------------------------------------------------------------*/
+static
DEFSETFUNC (pinduction)
{
induction *ip = item;
/*-----------------------------------------------------------------*/
/* pregion - prints loop information */
/*-----------------------------------------------------------------*/
+static
DEFSETFUNC (pregion)
{
region *lp = item;
printf ("\n");
return 0;
}
+#endif
/*-----------------------------------------------------------------*/
/* backEdges - returns a list of back edges */
/*-----------------------------------------------------------------*/
+static
DEFSETFUNC (backEdges)
{
edge *ep = item;
return succVect;
}
-
/*-----------------------------------------------------------------*/
/* loopInsert will insert a block into the loop set */
/*-----------------------------------------------------------------*/
-static void
+static void
loopInsert (set ** regionSet, eBBlock * block)
{
if (!isinSet (*regionSet, block))
/*-----------------------------------------------------------------*/
/* insertIntoLoop - insert item into loop */
/*-----------------------------------------------------------------*/
+static
DEFSETFUNC (insertIntoLoop)
{
eBBlock *ebp = item;
/*-----------------------------------------------------------------*/
/* isNotInBlocks - will return 1 if not is blocks */
/*-----------------------------------------------------------------*/
+static
DEFSETFUNC (isNotInBlocks)
{
eBBlock *ebp = item;
return 0;
}
+#if 0
/*-----------------------------------------------------------------*/
/* hasIncomingDefs - has definitions coming into the loop. i.e. */
/* check to see if the preheaders outDefs has any definitions */
/*-----------------------------------------------------------------*/
-int
+static int
hasIncomingDefs (region * lreg, operand * op)
{
eBBlock *preHdr = lreg->entry->preHeader;
/* findLoopEndSeq - will return the sequence number of the last */
/* iCode with the maximum dfNumber in the region */
/*-----------------------------------------------------------------*/
-int
+static int
findLoopEndSeq (region * lreg)
{
eBBlock *block;
return lblock->lSeq;
}
+#endif
/*-----------------------------------------------------------------*/
/* addToExitsMarkDepth - will add the the exitSet all blocks that */
/* have exits, will also update the depth field in the blocks */
/*-----------------------------------------------------------------*/
+static
DEFSETFUNC (addToExitsMarkDepth)
{
eBBlock *ebp = item;
V_ARG (region *, lr);
/* mark the loop depth of this block */
- if (!ebp->depth)
+ //if (!ebp->depth)
+ if (ebp->depth<depth)
ebp->depth = depth;
- /* put the loop region info in the block */
/* NOTE: here we will update only the inner most loop
that it is a part of */
if (!ebp->partOfLoop)
/*-----------------------------------------------------------------*/
/* createLoop - will create a set of region */
/*-----------------------------------------------------------------*/
+static
DEFSETFUNC (createLoop)
{
edge *ep = item;
/*-----------------------------------------------------------------*/
/* dominatedBy - will return 1 if item is dominated by block */
/*-----------------------------------------------------------------*/
+static
DEFSETFUNC (dominatedBy)
{
eBBlock *ebp = item;
/*-----------------------------------------------------------------*/
/* addDefInExprs - adds an expression into the inexpressions */
/*-----------------------------------------------------------------*/
+static
DEFSETFUNC (addDefInExprs)
{
eBBlock *ebp = item;
V_ARG (cseDef *, cdp);
- V_ARG (eBBlock **, ebbs);
- V_ARG (int, count);
+ V_ARG (ebbIndex *, ebbi);
addSetHead (&ebp->inExprs, cdp);
- cseBBlock (ebp, 0, ebbs, count);
+ cseBBlock (ebp, optimize.global_cse, ebbi);
return 0;
}
/*-----------------------------------------------------------------*/
/* assignmentsToSym - for a set of blocks determine # time assigned */
/*-----------------------------------------------------------------*/
-int
+static int
assignmentsToSym (set * sset, operand * sym)
{
eBBlock *ebp;
for (ebp = setFirstItem (blocks); ebp;
ebp = setNextItem (blocks))
{
-
/* get all the definitions for this symbol
in this block */
bitVect *defs = bitVectIntersect (ebp->ldefs, OP_DEFS (sym));
assigns += bitVectnBitsOn (defs);
- setToNull ((void **) &defs);
-
+ setToNull ((void *) &defs);
}
return assigns;
/*-----------------------------------------------------------------*/
/* isOperandInvariant - determines if an operand is an invariant */
/*-----------------------------------------------------------------*/
-int
+static int
isOperandInvariant (operand * op, region * theLoop, set * lInvars)
{
int opin = 0;
/*-----------------------------------------------------------------*/
/* pointerAssigned - will return 1 if pointer set found */
/*-----------------------------------------------------------------*/
+static
DEFSETFUNC (pointerAssigned)
{
eBBlock *ebp = item;
V_ARG (operand *, op);
- return ebp->hasFcall || bitVectBitValue (ebp->ptrsSet, op->key);
+ if (ebp->hasFcall)
+ return 1;
+
+ if (bitVectBitValue (ebp->ptrsSet, op->key))
+ return 1;
+
+ /* Unfortunately, one of the other pointer set operations */
+ /* may be using an alias of this operand, and the above */
+ /* test would miss it. To be thorough, some aliasing */
+ /* analysis should be done here. In the meantime, be */
+ /* conservative and assume any other pointer set operation */
+ /* is dangerous */
+ if (!bitVectIsZero (ebp->ptrsSet))
+ return 1;
+
+ return 0;
}
/*-----------------------------------------------------------------*/
/* hasNonPtrUse - returns true if operand has non pointer usage */
/*-----------------------------------------------------------------*/
+static
DEFSETFUNC (hasNonPtrUse)
{
eBBlock *ebp = item;
/*-----------------------------------------------------------------*/
/* loopInvariants - takes loop invariants out of region */
/*-----------------------------------------------------------------*/
-int
-loopInvariants (region * theLoop, eBBlock ** ebbs, int count)
+static int
+loopInvariants (region * theLoop, ebbIndex * ebbi)
{
+ eBBlock ** ebbs = ebbi->dfOrder;
+ int count = ebbi->count;
eBBlock *lBlock;
set *lInvars = NULL;
theLoop->exits == NULL)
return 0;
- /* we will do the elimination for those blocks */
- /* in the loop that dominates all exits from the loop */
+ /* we will do the elimination for those blocks */
+ /* in the loop that dominate all exits from the loop */
for (lBlock = setFirstItem (theLoop->regBlocks); lBlock;
lBlock = setNextItem (theLoop->regBlocks))
{
int lin, rin;
cseDef *ivar;
- /* if there are function calls in this block and this
- is a pointer get, the function could have changed it
- so skip, ISO-C99 according to David A. Long */
- if (fCallsInBlock && POINTER_GET(ic)) {
- continue;
+ /* TODO this is only needed if the call is between
+ here and the definition, but I am too lazy to do that now */
+
+ /* if there are function calls in this block */
+ if (fCallsInBlock) {
+
+ /* if this is a pointer get */
+ if (POINTER_GET(ic)) {
+ continue;
+ }
+
+ /* if this is an assignment from a global */
+ if (ic->op=='=' && isOperandGlobal(IC_RIGHT(ic))) {
+ continue;
+ }
}
if (SKIP_IC (ic) || POINTER_SET (ic) || ic->op == IFX)
continue;
+ /* iTemp assignment from a literal may be invariant, but it
+ will needlessly increase register pressure if the
+ iCode(s) that use this iTemp are not also invariant */
+ if (ic->op=='=' && IS_ITEMP (IC_RESULT (ic))
+ && IS_OP_LITERAL (IC_RIGHT (ic)))
+ continue;
+
/* if result is volatile then skip */
if (IC_RESULT (ic) &&
(isOperandVolatile (IC_RESULT (ic), TRUE) ||
continue;
lin = rin = 0;
-
+
/* special case */
/* if address of then it is an invariant */
if (ic->op == ADDRESS_OF &&
that the pointer set does not exist in
any of the blocks */
if (POINTER_GET (ic) &&
- (applyToSet (theLoop->regBlocks,
+ (applyToSet (theLoop->regBlocks,
pointerAssigned, IC_LEFT (ic))))
lin = 0;
}
-
+
/* do the same for right */
rin = isOperandInvariant (IC_RIGHT (ic), theLoop, lInvars);
-
+
/* if this is a POINTER_GET then special case, make sure all
usages within the loop are POINTER_GET any other usage
would mean that this is not an invariant , since the pointer
applyToSet (theLoop->regBlocks, hasNonPtrUse, IC_LEFT (ic)))
continue;
- /* if both the left & right are invariants : then check that */
- /* this definition exists in the out definition of all the */
- /* blocks, this will ensure that this is not assigned any */
- /* other value in the loop , and not used in this block */
+
+ /* if both the left & right are invariants : then check that */
+ /* this definition exists in the out definition of all the */
+ /* blocks, this will ensure that this is not assigned any */
+ /* other value in the loop, and not used in this block */
/* prior to this definition which means only this definition */
- /* is used in this loop */
+ /* is used in this loop */
if (lin && rin && IC_RESULT (ic))
{
eBBlock *sBlock;
set *lSet = setFromSet (theLoop->regBlocks);
- /* if this block does not dominate all exists */
+ /* if this block does not dominate all exits */
/* make sure this defintion is not used anywhere else */
if (!domsAllExits)
{
for (sBlock = setFirstItem (lSet); sBlock;
sBlock = setNextItem (lSet))
{
+ iCode *ic2;
+ int used;
+ int defDominates;
+
/* if this is the block make sure the definition */
/* reaches the end of the block */
if (sBlock == lBlock)
}
else if (bitVectBitsInCommon (sBlock->defSet, OP_DEFS (IC_RESULT (ic))))
break;
+
+ /* Check that this definition is not assigned */
+ /* any other value in this block. Also check */
+ /* that any usage in the block is dominated by */
+ /* by this definition. */
+ defDominates = bitVectBitValue (sBlock->domVect, lBlock->bbnum);
+ used = 0;
+ for (ic2 = sBlock->sch; ic2; ic2 = ic2->next)
+ {
+ if (ic2->op == IFX)
+ {
+ if (isOperandEqual (IC_RESULT (ic), IC_COND (ic2)))
+ used = 1;
+ }
+ else if (ic2->op == JUMPTABLE)
+ {
+ if (isOperandEqual (IC_RESULT (ic), IC_JTCOND (ic2)))
+ used = 1;
+ }
+ else
+ {
+ if (IC_LEFT (ic2) && isOperandEqual (IC_RESULT (ic), IC_LEFT (ic2)))
+ used = 1;
+ if (IC_RIGHT (ic2) && isOperandEqual (IC_RESULT (ic), IC_RIGHT (ic2)))
+ used = 1;
+ if ((ic != ic2) && (isOperandEqual(IC_RESULT(ic), IC_RESULT(ic2))))
+ break;
+ /* If used before this definition, might not be invariant */
+ if ((ic == ic2) && used)
+ break;
+ }
+ if (used && !defDominates)
+ break;
+ }
+ if (ic2) /* found another definition or a usage before the definition */
+ break;
}
if (sBlock)
continue; /* another definition present in the block */
+
- /* now check if it exists in the in of this block */
+ /* now check if it exists in the in of this block */
/* if not then it was killed before this instruction */
if (!bitVectBitValue (lBlock->inDefs, ic->key))
continue;
/* now we know it is a true invariant */
/* remove it from the insts chain & put */
/* in the invariant set */
- OP_SYMBOL (IC_RESULT (ic))->isinvariant = 1;
+
+ OP_SYMBOL (IC_RESULT (ic))->isinvariant = 1;
+ SPIL_LOC (IC_RESULT (ic)) = NULL;
remiCodeFromeBBlock (lBlock, ic);
/* maintain the data flow */
bitVectUnSetBit (lBlock->defSet, ic->key);
bitVectUnSetBit (lBlock->ldefs, ic->key);
ivar = newCseDef (IC_RESULT (ic), ic);
- applyToSet (theLoop->regBlocks, addDefInExprs, ivar, ebbs, count);
+ applyToSet (theLoop->regBlocks, addDefInExprs, ivar, ebbi);
addSet (&lInvars, ivar);
}
}
/*-----------------------------------------------------------------*/
/* addressTaken - returns true if the symbol is found in the addrof */
/*-----------------------------------------------------------------*/
-int
+static int
addressTaken (set * sset, operand * sym)
{
set *loop;
/*-----------------------------------------------------------------*/
/* findInduction :- returns 1 & the item if the induction is found */
/*-----------------------------------------------------------------*/
+static
DEFSETFUNC (findInduction)
{
induction *ip = item;
/*-----------------------------------------------------------------*/
/* findDefInRegion - finds the definition within the region */
/*-----------------------------------------------------------------*/
-iCode *
+static iCode *
findDefInRegion (set * regBlocks, operand * defOp, eBBlock ** owner)
{
eBBlock *lBlock;
return NULL;
}
+/*-----------------------------------------------------------------*/
+/* addPostLoopBlock - add a ebblock before the successors of the */
+/* loop exits */
+/*-----------------------------------------------------------------*/
+static void
+addPostLoopBlock (region *loopReg, ebbIndex *ebbi, iCode *ic)
+{
+ bitVect *loopSuccs;
+ int i;
+
+ /* if the number of exits is greater than one then
+ we use another trick: we will create an intersection
+ of succesors of the exits, then take those that are not
+ part of the loop and have dfNumber greater loop entry (eblock),
+ insert a new predecessor postLoopBlk before them and add
+ a copy of ic in the new block. The postLoopBlk in between
+ is necessary, because the old successors of the loop exits can
+ be successors of other blocks too: see bug-136564. */
+
+ /* loopSuccs now contains intersection
+ of all the loops successors */
+ loopSuccs = intersectLoopSucc (loopReg->exits, ebbi->dfOrder);
+ if (!loopSuccs)
+ return;
+
+ for (i = 0; i < loopSuccs->size; i++)
+ {
+ eBBlock *eblock = NULL;
+ eBBlock *postLoopBlk;
+ iCode *newic;
+ int j;
+
+ if (!bitVectBitValue (loopSuccs, i))
+ continue;
+
+ /* Need to search for bbnum == i since ebbi->dfOrder is
+ sorted by dfnum; a direct index won't do. */
+ for (j = 0; j < ebbi->count; j++)
+ if (ebbi->dfOrder[j]->bbnum == i)
+ {
+ eblock = ebbi->dfOrder[j];
+ break;
+ }
+ assert(eblock);
+
+ /* if the successor does not belong to the loop
+ and will be executed after the loop : then
+ add a definition to the block */
+ if (isinSet (loopReg->regBlocks, eblock))
+ continue;
+ if (eblock->dfnum <= loopReg->entry->dfnum)
+ continue;
+
+ /* look for an existing loopExitBlock */
+ if (strncmp (LOOPEXITLBL,
+ eblock->entryLabel->name,
+ sizeof(LOOPEXITLBL) - 1) == 0)
+ {
+ /* reuse the existing one */
+ postLoopBlk = eblock;
+ }
+ else
+ {
+ /* create and insert a new eBBlock.
+ Damn, that's messy ... */
+ int i;
+ set *oldPredList;
+ eBBlock *ebpi;
+
+ postLoopBlk = neweBBlock();
+
+ /* create a loopExit-label */
+ postLoopBlk->entryLabel = newiTempLoopHeaderLabel (0);
+
+ /* increase bbnum for all blocks after
+ (and including) eblock */
+ for (i = 0; i < ebbi->count; i++)
+ {
+ if (ebbi->bbOrder[i]->bbnum >= eblock->bbnum)
+ ++ebbi->bbOrder[i]->bbnum;
+ }
+ /* insert postLoopBlk before bbnum */
+ postLoopBlk->bbnum = eblock->bbnum - 1;
+
+ ++ebbi->count;
+
+ /* these arrays need one more block, which ... */
+ ebbi->bbOrder = Safe_realloc (ebbi->bbOrder,
+ (ebbi->count + 1) * sizeof(eBBlock *));
+ /* ... must be initialized with 0 */
+ ebbi->bbOrder[ebbi->count] = NULL;
+ /* move the blocks up ... */
+ memmove (&ebbi->bbOrder[postLoopBlk->bbnum + 1],
+ &ebbi->bbOrder[postLoopBlk->bbnum],
+ (ebbi->count - postLoopBlk->bbnum - 1) * sizeof(eBBlock *));
+ /* ... and insert postLoopBlk */
+ ebbi->bbOrder[postLoopBlk->bbnum] = postLoopBlk;
+
+ /* just add postLoopBlk at the end of dfOrder,
+ computeControlFlow() will compute the new dfnum */
+ ebbi->dfOrder = Safe_realloc (ebbi->dfOrder,
+ (ebbi->count + 1) * sizeof(eBBlock *));
+ ebbi->dfOrder[ebbi->count] = NULL;
+ ebbi->dfOrder[ebbi->count - 1] = postLoopBlk;
+
+ /* copy loop information from eblock to postLoopBlk */
+ if (eblock->partOfLoop)
+ {
+ postLoopBlk->partOfLoop = eblock->partOfLoop;
+ /* add postLoopBlk to loop region */
+ addSetHead (&postLoopBlk->partOfLoop->regBlocks, postLoopBlk);
+ }
+
+ /* go through loop exits and replace the old exit block eblock
+ with the new postLoopBlk */
+ for (ebpi = setFirstItem (loopReg->exits);
+ ebpi;
+ ebpi = setNextItem (loopReg->exits))
+ {
+ /* replace old label with new label */
+ replaceLabel (ebpi, eblock->entryLabel, postLoopBlk->entryLabel);
+ }
+
+ /* now eblock is replaced by postLoopBlk.
+ It's possible, that eblock has an immediate predecessor
+ (with ebpi->bbnum + 1 == eblock->bbnum), which isn't part of the
+ loop. This predecessor must stay predecessor of eblock, not of
+ postLoopBlk. But now postLoopBlk is in between, therefore a GOTO
+ from this predecessor to eblock must be appended.
+ Example: bug-136564.c */
+
+ /* take all predecessors and subtract the loop exits */
+ oldPredList = subtractFromSet (eblock->predList,
+ loopReg->exits,
+ THROW_NONE);
+ for (ebpi = setFirstItem (oldPredList);
+ ebpi;
+ ebpi = setNextItem (oldPredList))
+ {
+ /* Is it an immediate predecessor (without GOTO)?
+ All other predecessors end with a
+ GOTO, IF, IFX or JUMPTABLE: nothing to to do */
+ if (ebpi->bbnum + 1 == postLoopBlk->bbnum)
+ {
+ /* insert goto to old predecessor of eblock */
+ newic = newiCodeLabelGoto (GOTO, eblock->entryLabel);
+ addiCodeToeBBlock (ebpi, newic, NULL);
+ break; /* got it, only one is possible */
+ }
+ }
+
+ /* set the label */
+ postLoopBlk->sch =
+ postLoopBlk->ech = newiCodeLabelGoto (LABEL, postLoopBlk->entryLabel);
+ }
+
+ /* create the definition in postLoopBlk */
+ newic = newiCode ('=', NULL, operandFromOperand (IC_RIGHT (ic)));
+ IC_RESULT (newic) = operandFromOperand (IC_RESULT (ic));
+ /* maintain data flow */
+ OP_DEFS(IC_RESULT (newic)) = bitVectSetBit (OP_DEFS (IC_RESULT (newic)),
+ newic->key);
+ OP_USES(IC_RIGHT (newic)) = bitVectSetBit (OP_USES (IC_RIGHT (newic)),
+ newic->key);
+
+ /* and add it */
+ addiCodeToeBBlock (postLoopBlk, newic, NULL);
+ postLoopBlk->sch->lineno =
+ postLoopBlk->ech->lineno = eblock->sch->lineno;
+
+ /* outDefs is needed by computeControlFlow(), anything
+ else will be set up by computeControlFlow() */
+ postLoopBlk->outDefs = bitVectSetBit (postLoopBlk->outDefs, newic->key);
+ } /* for (i = 0; i < loopSuccs->size; i++) */
+
+ /* the postLoopBlk and the induction significantly
+ changed the control flow, recompute it */
+ computeControlFlow (ebbi);
+}
+
/*-----------------------------------------------------------------*/
/* basicInduction - finds the basic induction variables in a loop */
/*-----------------------------------------------------------------*/
-set *
-basicInduction (region * loopReg, eBBlock ** ebbs, int count)
+static set *
+basicInduction (region * loopReg, ebbIndex * ebbi)
{
eBBlock *lBlock;
set *indVars = NULL;
{
operand *aSym;
- unsigned long litValue;
+ long litValue;
induction *ip;
iCode *indIc;
eBBlock *owner = NULL;
int nexits;
-
- /* look for assignments of the form */
+ sym_link *optype;
+
+ /* To find an induction variable, we need to */
+ /* find within the loop three iCodes in this */
+ /* general form: */
+ /* */
+ /* ddic: iTempB := symbolVar */
+ /* dic: iTempA := iTempB + lit */
+ /* or iTempA := iTempB - lit */
+ /* or iTempA := lit + iTempB */
+ /* ic: symbolVar := iTempA */
+ /* */
+ /* (symbolVar may also be an iTemp if it is */
+ /* register equivalent) */
+
+ /* look for assignments of the form */
/* symbolVar := iTempNN */
if (ic->op != '=')
continue;
if (addressTaken (loopReg->regBlocks, IC_RESULT (ic)))
continue;
+ /* Only consider variables with integral type. */
+ /* (2004/12/06 - EEP - ds390 fails regression tests unless */
+ /* pointers are also considered for induction (due to some */
+ /* register alloctaion bugs). Remove !IS_PTR clause when */
+ /* that gets fixed) */
+ optype = operandType (IC_RIGHT (ic));
+ if (!IS_INTEGRAL (optype) && !IS_PTR (optype))
+ continue;
+
/* find the definition for the result in the block */
if (!(dic = findDefInRegion (setFromSet (loopReg->regBlocks),
IC_RIGHT (ic), &owner)))
/* if not +/- continue */
if (dic->op != '+' && dic->op != '-')
continue;
-
+
/* make sure definition is of the form a +/- c */
if (!IS_OP_LITERAL (IC_LEFT (dic)) && !IS_OP_LITERAL (IC_RIGHT (dic)))
continue;
+
+ /* make sure the definition found is the only one */
+ if (assignmentsToSym (loopReg->regBlocks, IC_RIGHT (ic)) > 1)
+ continue;
- aSym = (IS_OP_LITERAL (IC_RIGHT (dic)) ?
- (litValue = (unsigned long) operandLitValue (IC_RIGHT (dic)), IC_LEFT (dic)) :
- (litValue = (unsigned long) operandLitValue (IC_LEFT (dic)), IC_RIGHT (dic)));
+ if (IS_OP_LITERAL (IC_RIGHT (dic)))
+ {
+ aSym = IC_LEFT (dic);
+ litValue = (long) operandLitValue (IC_RIGHT (dic));
+ }
+ else
+ {
+ /* For minus, the literal must not be on the left side. */
+ /* (Actually, this case could be handled, but it's probably */
+ /* not worth the extra code) */
+ if (dic->op == '-')
+ continue;
+ aSym = IC_RIGHT (dic);
+ litValue = (long) operandLitValue (IC_LEFT (dic));
+ }
if (!isOperandEqual (IC_RESULT (ic), aSym) &&
!isOperandEqual (IC_RIGHT (ic), aSym))
/* replace the inducted variable by the iTemp */
replaceSymBySym (loopReg->regBlocks, IC_RESULT (ic), IC_RIGHT (ic));
-
- /* if it has only one exit then remove it from here
- and put it in the exit block */
- nexits = elementsInSet (loopReg->exits);
- if (nexits == 1)
- {
- eBBlock *exit = setFirstItem (loopReg->exits);
-
- /* if it is the same block then there is no
- need to move it about */
- if (exit != lBlock)
- {
- iCode *saveic = ic->prev;
- /* remove it */
- remiCodeFromeBBlock (lBlock, ic);
- /* clear the definition */
- bitVectUnSetBit (lBlock->defSet, ic->key);
- /* add it to the exit */
- addiCodeToeBBlock (exit, ic, NULL);
- /* set the definition bit */
- exit->defSet = bitVectSetBit (exit->defSet, ic->key);
- ic = saveic;
- }
- }
-
- /* if the number of exits is greater than one then
- we use another trick ; we will create an intersection
- of succesors of the exits, then take those that are not
- part of the loop and have dfNumber greater loop entry
- and insert a new definition in them */
- if (nexits > 1)
- {
-
- bitVect *loopSuccs = intersectLoopSucc (loopReg->exits, ebbs);
-
- /* loopSuccs now contains intersection
- of all the loops successors */
- if (loopSuccs)
- {
- int i;
- for (i = 0; i < loopSuccs->size; i++)
- {
- if (bitVectBitValue (loopSuccs, i))
- {
-
- eBBlock *eblock = ebbs[i];
-
- /* if the successor does not belong to the loop
- and will be executed after the loop : then
- add a definition to the block */
- if (!isinSet (loopReg->regBlocks, eblock) &&
- eblock->dfnum > loopReg->entry->dfnum)
- {
- /* create the definition */
- iCode *newic = newiCode ('=', NULL,
- operandFromOperand (IC_RIGHT (ic)));
- IC_RESULT (newic) = operandFromOperand (IC_RESULT (ic));
- OP_DEFS (IC_RESULT (newic)) =
- bitVectSetBit (OP_DEFS (IC_RESULT (newic)), newic->key);
- OP_USES (IC_RIGHT (newic)) =
- bitVectSetBit (OP_USES (IC_RIGHT (newic)), newic->key);
- /* and add it */
- if (eblock->sch && eblock->sch->op == LABEL)
- addiCodeToeBBlock (eblock, newic, eblock->sch->next);
- else
- addiCodeToeBBlock (eblock, newic, eblock->sch);
- /* set the definition bit */
- eblock->defSet = bitVectSetBit (eblock->defSet, ic->key);
- }
- }
- }
- }
- }
-
- addSet (&indVars, ip);
- }
-
- } /* end of all blocks for basic induction variables */
+ /* ic should now be moved to the exit block(s) */
+
+ nexits = elementsInSet (loopReg->exits);
+ if (nexits == 0)
+ {
+ /* this is a endless loop without exits: there's
+ no need to restore the inducted variable */
+ iCode *saveic = ic->prev;
+
+ /* ic will be removed by killDeadCode() too,
+ but it's a nice to see a clean dumploop now. */
+ remiCodeFromeBBlock (lBlock, ic);
+ /* clear the definition */
+ bitVectUnSetBit (lBlock->defSet, ic->key);
+ ic = saveic;
+ }
+ else
+ addPostLoopBlock (loopReg, ebbi, ic);
+ addSet (&indVars, ip);
+ } /* for ic */
+ } /* end of all blocks for basic induction variables */
return indVars;
}
/*-----------------------------------------------------------------*/
/* loopInduction - remove induction variables from a loop */
/*-----------------------------------------------------------------*/
-int
-loopInduction (region * loopReg, eBBlock ** ebbs, int count)
+static int
+loopInduction (region * loopReg, ebbIndex * ebbi)
{
int change = 0;
- eBBlock *lBlock, *lastBlock = NULL;
+ eBBlock *lBlock, *owner, *lastBlock = NULL;
set *indVars = NULL;
set *basicInd = NULL;
return 0;
/* we first determine the basic Induction variables */
- basicInd = setFromSet (indVars = basicInduction (loopReg, ebbs, count));
+ basicInd = setFromSet (indVars = basicInduction (loopReg, ebbi));
/* find other induction variables : by other we mean definitions of */
/* the form x := y (* | / ) <constant> .. we will move this one to */
lBlock = setNextItem (loopReg->regBlocks))
{
- iCode *ic, *indIc;
+ iCode *ic, *indIc, *dic;
induction *ip;
/* last block is the one with the highest block
for (ic = lBlock->sch; ic; ic = ic->next)
{
operand *aSym;
- unsigned long litVal;
- int lr = 0;
+ long litVal;
/* consider only * & / */
if (ic->op != '*' && ic->op != '/')
continue;
- /* if the result has more definitions then */
+ /* only consider variables with integral type */
+ if (!IS_INTEGRAL (operandType (IC_RESULT (ic))))
+ continue;
+
+ /* if the result has more definitions then */
if (assignmentsToSym (loopReg->regBlocks, IC_RESULT (ic)) > 1)
continue;
(IS_OP_LITERAL (IC_LEFT (ic)) && IS_SYMOP (IC_RIGHT (ic)))))
continue;
- aSym = (IS_SYMOP (IC_LEFT (ic)) ?
- (lr = 1, litVal = (unsigned long) operandLitValue (IC_RIGHT (ic)), IC_LEFT (ic)) :
- (litVal = (unsigned long) operandLitValue (IC_LEFT (ic)), IC_RIGHT (ic)));
+ if (IS_SYMOP (IC_LEFT (ic)))
+ {
+ aSym = IC_LEFT (ic);
+ litVal = (long) operandLitValue (IC_RIGHT (ic));
+ }
+ else
+ {
+ /* For division, the literal must not be on the left side */
+ if (ic->op == '/')
+ continue;
+ aSym = IC_RIGHT (ic);
+ litVal = (long) operandLitValue (IC_LEFT (ic));
+ }
ip = NULL;
/* check if this is an induction variable */
addSet (&indVars,
newInduction (IC_RESULT (ic), ip->op, litVal, indIc, NULL));
- /* now change this instruction */
- ic->op = ip->op;
- if (lr)
- {
- IC_LEFT (ic) = operandFromOperand (IC_RESULT (ic));
- IC_RIGHT (ic) = operandFromLit (litVal);
- }
- else
- {
- IC_RIGHT (ic) = operandFromOperand (IC_RESULT (ic));
- IC_LEFT (ic) = operandFromLit (litVal);
- }
-
- /* we need somemore initialisation code */
- /* we subtract the litVal from itself if increment */
- if (ic->op == '+')
- {
- indIc = newiCode ('-',
- operandFromOperand (IC_RESULT (ic)),
- operandFromLit (litVal));
- indIc->lineno = ic->lineno;
- IC_RESULT (indIc) = operandFromOperand (IC_RESULT (ic));
+ /* Replace mul/div with assignment to self; killDeadCode() will */
+ /* clean this up since we can't use remiCodeFromeBBlock() here. */
+ ic->op = '=';
+ IC_LEFT (ic) = NULL;
+ IC_RIGHT (ic) = IC_RESULT (ic);
+
+ /* Insert an update of the induction variable just before */
+ /* the update of the basic induction variable. */
+ indIc = newiCode (ip->op,
+ operandFromOperand (IC_RESULT (ic)),
+ operandFromLit (litVal));
+ IC_RESULT (indIc) = operandFromOperand (IC_RESULT (ic));
+ owner = NULL;
+ dic = findDefInRegion (setFromSet (loopReg->regBlocks), aSym, &owner);
+ assert (dic);
+ addiCodeToeBBlock (owner, indIc, dic);
- addSet (&indVars,
- newInduction (IC_RESULT (ic), ip->op, litVal, indIc, NULL));
- }
}
}
ip;
ip = setNextItem (indVars))
{
-
indVect = bitVectSetBit (indVect, ip->ic->key);
ip->ic->lineno = preHdr->ech->lineno;
if (!icFirst)
/* add the induction variable vector to the last
block in the loop */
lastBlock->isLastInLoop = 1;
- lastBlock->linds = indVect;
+ lastBlock->linds = bitVectUnion(lastBlock->linds,indVect);
}
- setToNull ((void **) &indVars);
+ setToNull ((void *) &indVars);
return change;
}
/*-----------------------------------------------------------------*/
/* mergeRegions - will merge region with same entry point */
/*-----------------------------------------------------------------*/
+static
DEFSETFUNC (mergeRegions)
{
region *theLoop = item;
if (lp->entry == theLoop->entry)
{
theLoop->regBlocks = unionSets (theLoop->regBlocks,
- lp->regBlocks, THROW_BOTH);
+ lp->regBlocks, THROW_DEST);
lp->merged = 1;
}
}
/*-----------------------------------------------------------------*/
/* ifMerged - return 1 if the merge flag is 1 */
/*-----------------------------------------------------------------*/
+static
DEFSETFUNC (ifMerged)
{
region *lp = item;
/*-----------------------------------------------------------------*/
/* mergeInnerLoops - will merge into body when entry is present */
/*-----------------------------------------------------------------*/
+static
DEFSETFUNC (mergeInnerLoops)
{
region *theLoop = item;
/* createLoopRegions - will detect and create a set of natural loops */
/*-----------------------------------------------------------------*/
hTab *
-createLoopRegions (eBBlock ** ebbs, int count)
+createLoopRegions (ebbIndex * ebbi)
{
set *allRegion = NULL; /* set of all loops */
hTab *orderedLoops = NULL;
applyToSet (allRegion, mergeInnerLoops, allRegion, &maxDepth);
maxDepth++;
+
/* now create all the exits .. also */
/* create an ordered set of loops */
/* i.e. we process loops in the inner to outer order */
/*-----------------------------------------------------------------*/
/* loopOptimizations - identify region & remove invariants & ind */
/*-----------------------------------------------------------------*/
-int
-loopOptimizations (hTab * orderedLoops, eBBlock ** ebbs, int count)
+int
+loopOptimizations (hTab * orderedLoops, ebbIndex * ebbi)
{
region *lp;
int change = 0;
{
if (optimize.loopInvariant)
- change += loopInvariants (lp, ebbs, count);
+ change += loopInvariants (lp, ebbi);
if (optimize.loopInduction)
- change += loopInduction (lp, ebbs, count);
+ change += loopInduction (lp, ebbi);
}
return change;
projects / fw / sdcc / blobdiff