mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-07-19 03:29:22 +00:00
Rename bunch of variables.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@41250 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Devang Patel
parent
60cbab4252
commit
0b8e02b704
@ -705,90 +705,95 @@ void LoopIndexSplit::removeBlocks(BasicBlock *DeadBB, Loop *LP,
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}
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/// splitLoop - Split current loop L in two loops using split information
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/// SD. Update dominator information. Maintain LCSSA form.
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bool LoopIndexSplit::splitLoop(SplitInfo &SD) {
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BasicBlock *Preheader = L->getLoopPreheader();
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BasicBlock *SplitBlock = SD.SplitCondition->getParent();
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BasicBlock *Latch = L->getLoopLatch();
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BasicBlock *Header = L->getHeader();
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BranchInst *SplitTerminator = cast<BranchInst>(SplitBlock->getTerminator());
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// True loop is original loop. False loop is cloned loop.
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BasicBlock *TL_Preheader = L->getLoopPreheader();
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BasicBlock *TL_SplitCondBlock = SD.SplitCondition->getParent();
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BasicBlock *TL_Latch = L->getLoopLatch();
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BasicBlock *TL_Header = L->getHeader();
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BranchInst *TL_SplitTerminator =
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cast<BranchInst>(TL_SplitCondBlock->getTerminator());
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// FIXME - Unable to handle triange loops at the moment.
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// In triangle loop, split condition is in header and one of the
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// the split destination is loop latch. If split condition is EQ
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// then such loops are already handle in processOneIterationLoop().
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if (Header == SplitBlock
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&& (Latch == SplitTerminator->getSuccessor(0)
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|| Latch == SplitTerminator->getSuccessor(1)))
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BasicBlock *Succ0 = TL_SplitTerminator->getSuccessor(0);
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BasicBlock *Succ1 = TL_SplitTerminator->getSuccessor(1);
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if (TL_Header == TL_SplitCondBlock
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&& (TL_Latch == Succ0 || TL_Latch == Succ1))
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return false;
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// If one of the split condition branch is post dominating other then loop
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// index split is not appropriate.
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BasicBlock *Succ0 = SplitTerminator->getSuccessor(0);
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BasicBlock *Succ1 = SplitTerminator->getSuccessor(1);
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if (DT->dominates(Succ0, Latch) || DT->dominates(Succ1, Latch))
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if (DT->dominates(Succ0, TL_Latch) || DT->dominates(Succ1, TL_Latch))
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return false;
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// If one of the split condition branch is a predecessor of the other
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// split condition branch head then do not split loop on this condition.
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for(pred_iterator PI = pred_begin(Succ0), PE = pred_end(Succ0); PI != PE; ++PI)
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for(pred_iterator PI = pred_begin(Succ0), PE = pred_end(Succ0);
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PI != PE; ++PI)
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if (Succ1 == *PI)
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return false;
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for(pred_iterator PI = pred_begin(Succ1), PE = pred_end(Succ1); PI != PE; ++PI)
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for(pred_iterator PI = pred_begin(Succ1), PE = pred_end(Succ1);
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PI != PE; ++PI)
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if (Succ0 == *PI)
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return false;
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// True loop is original loop. False loop is cloned loop.
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bool SignedPredicate = ExitCondition->isSignedPredicate();
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//[*] Calculate True loop's new Exit Value in loop preheader.
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// TLExitValue = min(SplitValue, ExitValue)
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// TL_ExitValue = min(SplitValue, ExitValue)
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//[*] Calculate False loop's new Start Value in loop preheader.
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// FLStartValue = min(SplitValue, TrueLoop.StartValue)
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Value *TLExitValue = NULL;
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Value *FLStartValue = NULL;
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// FL_StartValue = min(SplitValue, TrueLoop.StartValue)
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Value *TL_ExitValue = NULL;
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Value *FL_StartValue = NULL;
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if (isa<ConstantInt>(SD.SplitValue)) {
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TLExitValue = SD.SplitValue;
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FLStartValue = SD.SplitValue;
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TL_ExitValue = SD.SplitValue;
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FL_StartValue = SD.SplitValue;
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}
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else {
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Instruction *TL_PHTerminator = TL_Preheader->getTerminator();
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Value *C1 = new ICmpInst(SignedPredicate ?
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ICmpInst::ICMP_SLT : ICmpInst::ICMP_ULT,
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SD.SplitValue,
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ExitCondition->getOperand(ExitValueNum),
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"lsplit.ev",
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Preheader->getTerminator());
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TLExitValue = new SelectInst(C1, SD.SplitValue,
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"lsplit.ev", TL_PHTerminator);
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TL_ExitValue = new SelectInst(C1, SD.SplitValue,
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ExitCondition->getOperand(ExitValueNum),
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"lsplit.ev", Preheader->getTerminator());
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"lsplit.ev", TL_PHTerminator);
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Value *C2 = new ICmpInst(SignedPredicate ?
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ICmpInst::ICMP_SLT : ICmpInst::ICMP_ULT,
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SD.SplitValue, StartValue, "lsplit.sv",
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Preheader->getTerminator());
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FLStartValue = new SelectInst(C2, SD.SplitValue, StartValue,
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"lsplit.sv", Preheader->getTerminator());
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TL_PHTerminator);
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FL_StartValue = new SelectInst(C2, SD.SplitValue, StartValue,
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"lsplit.sv", TL_Preheader->getTerminator());
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}
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//[*] Clone loop. Avoid true destination of split condition and
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// the blocks dominated by true destination.
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DenseMap<const Value *, Value *> ValueMap;
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Loop *FalseLoop = CloneLoop(L, LPM, LI, ValueMap, this);
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BasicBlock *FalseHeader = FalseLoop->getHeader();
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BasicBlock *FL_Header = FalseLoop->getHeader();
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//[*] True loop's exit edge enters False loop.
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PHINode *IndVarClone = cast<PHINode>(ValueMap[IndVar]);
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BasicBlock *ExitingBlock = ExitCondition->getParent();
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BranchInst *ExitInsn = dyn_cast<BranchInst>(ExitingBlock->getTerminator());
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assert (ExitInsn && "Unable to find suitable loop exit branch");
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BasicBlock *ExitDest = ExitInsn->getSuccessor(1);
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if (L->contains(ExitDest)) {
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ExitDest = ExitInsn->getSuccessor(0);
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ExitInsn->setSuccessor(0, FalseHeader);
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PHINode *FL_IndVar = cast<PHINode>(ValueMap[IndVar]);
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BasicBlock *TL_ExitingBlock = ExitCondition->getParent();
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BranchInst *TL_ExitInsn =
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dyn_cast<BranchInst>(TL_ExitingBlock->getTerminator());
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assert (TL_ExitInsn && "Unable to find suitable loop exit branch");
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BasicBlock *TL_ExitDest = TL_ExitInsn->getSuccessor(1);
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if (L->contains(TL_ExitDest)) {
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TL_ExitDest = TL_ExitInsn->getSuccessor(0);
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TL_ExitInsn->setSuccessor(0, FL_Header);
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} else
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ExitInsn->setSuccessor(1, FalseHeader);
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TL_ExitInsn->setSuccessor(1, FL_Header);
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// Collect inverse map of Header PHINodes.
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DenseMap<Value *, Value *> InverseMap;
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for (BasicBlock::iterator BI = L->getHeader()->begin(),
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@ -799,67 +804,70 @@ bool LoopIndexSplit::splitLoop(SplitInfo &SD) {
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} else
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break;
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}
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// Update False loop's header
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for (BasicBlock::iterator BI = FalseHeader->begin(), BE = FalseHeader->end();
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for (BasicBlock::iterator BI = FL_Header->begin(), BE = FL_Header->end();
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BI != BE; ++BI) {
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if (PHINode *PN = dyn_cast<PHINode>(BI)) {
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PN->removeIncomingValue(Preheader);
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if (PN == IndVarClone)
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PN->addIncoming(FLStartValue, ExitingBlock);
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PN->removeIncomingValue(TL_Preheader);
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if (PN == FL_IndVar)
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PN->addIncoming(FL_StartValue, TL_ExitingBlock);
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else {
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PHINode *OrigPN = cast<PHINode>(InverseMap[PN]);
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Value *V2 = OrigPN->getIncomingValueForBlock(ExitingBlock);
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PN->addIncoming(V2, ExitingBlock);
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Value *V2 = OrigPN->getIncomingValueForBlock(TL_ExitingBlock);
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PN->addIncoming(V2, TL_ExitingBlock);
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}
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} else
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break;
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}
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// Update ExitDest. Now it's predecessor is False loop's exit block.
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BasicBlock *ExitingBlockClone = cast<BasicBlock>(ValueMap[ExitingBlock]);
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for (BasicBlock::iterator BI = ExitDest->begin(), BE = ExitDest->end();
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// Update TL_ExitDest. Now it's predecessor is False loop's exit block.
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BasicBlock *FL_ExitingBlock = cast<BasicBlock>(ValueMap[TL_ExitingBlock]);
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for (BasicBlock::iterator BI = TL_ExitDest->begin(), BE = TL_ExitDest->end();
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BI != BE; ++BI) {
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if (PHINode *PN = dyn_cast<PHINode>(BI)) {
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PN->addIncoming(ValueMap[PN->getIncomingValueForBlock(ExitingBlock)], ExitingBlockClone);
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PN->removeIncomingValue(ExitingBlock);
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PN->addIncoming(ValueMap[PN->getIncomingValueForBlock(TL_ExitingBlock)],
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FL_ExitingBlock);
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PN->removeIncomingValue(TL_ExitingBlock);
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} else
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break;
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}
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if (DT) {
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DT->changeImmediateDominator(FalseHeader, ExitingBlock);
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DT->changeImmediateDominator(ExitDest, cast<BasicBlock>(ValueMap[ExitingBlock]));
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DT->changeImmediateDominator(FL_Header, TL_ExitingBlock);
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DT->changeImmediateDominator(TL_ExitDest,
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cast<BasicBlock>(ValueMap[TL_ExitingBlock]));
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}
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assert (!L->contains(ExitDest) && " Unable to find exit edge destination");
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assert (!L->contains(TL_ExitDest) && " Unable to find exit edge destination");
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//[*] Split Exit Edge.
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BasicBlock *TL_ExitBlock = SplitEdge(ExitingBlock, FalseHeader, this);
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BasicBlock *TL_ExitBlock = SplitEdge(TL_ExitingBlock, FL_Header, this);
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//[*] Eliminate split condition's false branch from True loop.
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BranchInst *BR = cast<BranchInst>(SplitBlock->getTerminator());
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BasicBlock *FBB = BR->getSuccessor(1);
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BR->setUnconditionalDest(BR->getSuccessor(0));
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removeBlocks(FBB, L, BR->getSuccessor(0));
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BranchInst *TL_BR = cast<BranchInst>(TL_SplitCondBlock->getTerminator());
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BasicBlock *TL_FalseBlock = TL_BR->getSuccessor(1);
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TL_BR->setUnconditionalDest(TL_BR->getSuccessor(0));
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removeBlocks(TL_FalseBlock, L, TL_BR->getSuccessor(0));
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//[*] Update True loop's exit value using new exit value.
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ExitCondition->setOperand(ExitValueNum, TLExitValue);
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ExitCondition->setOperand(ExitValueNum, TL_ExitValue);
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//[*] Eliminate split condition's true branch in False loop CFG.
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BasicBlock *FSplitBlock = cast<BasicBlock>(ValueMap[SplitBlock]);
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BranchInst *FBR = cast<BranchInst>(FSplitBlock->getTerminator());
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BasicBlock *TBB = FBR->getSuccessor(0);
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FBR->setUnconditionalDest(FBR->getSuccessor(1));
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removeBlocks(TBB, FalseLoop, cast<BasicBlock>(FBR->getSuccessor(0)));
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BasicBlock *FL_SplitCondBlock = cast<BasicBlock>(ValueMap[TL_SplitCondBlock]);
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BranchInst *FL_BR = cast<BranchInst>(FL_SplitCondBlock->getTerminator());
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BasicBlock *FL_TrueBlock = FL_BR->getSuccessor(0);
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FL_BR->setUnconditionalDest(FL_BR->getSuccessor(1));
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removeBlocks(FL_TrueBlock, FalseLoop,
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cast<BasicBlock>(FL_BR->getSuccessor(0)));
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//[*] Preserve LCSSA
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for(BasicBlock::iterator BI = FalseHeader->begin(), BE = FalseHeader->end();
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for(BasicBlock::iterator BI = FL_Header->begin(), BE = FL_Header->end();
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BI != BE; ++BI) {
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if (PHINode *PN = dyn_cast<PHINode>(BI)) {
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Value *V1 = PN->getIncomingValueForBlock(TL_ExitBlock);
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PHINode *newPHI = new PHINode(PN->getType(), PN->getName());
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newPHI->addIncoming(V1, ExitingBlock);
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newPHI->addIncoming(V1, TL_ExitingBlock);
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TL_ExitBlock->getInstList().push_front(newPHI);
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PN->removeIncomingValue(TL_ExitBlock);
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PN->addIncoming(newPHI, TL_ExitBlock);
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@ -869,4 +877,3 @@ bool LoopIndexSplit::splitLoop(SplitInfo &SD) {
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return true;
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}
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