#include "llvm/ADT/DenseMap.h"
#include "llvm/ADT/SmallPtrSet.h"
-#include "llvm/ADT/SmallPtrSet.h"
#include "llvm/ADT/SmallVector.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Analysis/AssumptionCache.h"
#include "llvm/Analysis/CodeMetrics.h"
-#include "llvm/Analysis/LegacyDivergenceAnalysis.h"
#include "llvm/Analysis/InstructionSimplify.h"
+#include "llvm/Analysis/LegacyDivergenceAnalysis.h"
#include "llvm/Analysis/LoopInfo.h"
+#include "llvm/Analysis/LoopIterator.h"
#include "llvm/Analysis/LoopPass.h"
+#include "llvm/Analysis/MemorySSA.h"
+#include "llvm/Analysis/MemorySSAUpdater.h"
#include "llvm/Analysis/ScalarEvolution.h"
#include "llvm/Analysis/TargetTransformInfo.h"
-#include "llvm/Transforms/Utils/Local.h"
#include "llvm/IR/Attributes.h"
#include "llvm/IR/BasicBlock.h"
#include "llvm/IR/CallSite.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Transforms/Scalar.h"
+#include "llvm/Transforms/Scalar/LoopPassManager.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/Transforms/Utils/Cloning.h"
+#include "llvm/Transforms/Utils/Local.h"
#include "llvm/Transforms/Utils/LoopUtils.h"
#include "llvm/Transforms/Utils/ValueMapper.h"
#include <algorithm>
Loop *currentLoop = nullptr;
DominatorTree *DT = nullptr;
+ MemorySSA *MSSA = nullptr;
+ std::unique_ptr<MemorySSAUpdater> MSSAU;
BasicBlock *loopHeader = nullptr;
BasicBlock *loopPreheader = nullptr;
void getAnalysisUsage(AnalysisUsage &AU) const override {
AU.addRequired<AssumptionCacheTracker>();
AU.addRequired<TargetTransformInfoWrapperPass>();
+ if (EnableMSSALoopDependency) {
+ AU.addRequired<MemorySSAWrapperPass>();
+ AU.addPreserved<MemorySSAWrapperPass>();
+ }
if (hasBranchDivergence)
AU.addRequired<LegacyDivergenceAnalysis>();
getLoopAnalysisUsage(AU);
INITIALIZE_PASS_DEPENDENCY(LoopPass)
INITIALIZE_PASS_DEPENDENCY(TargetTransformInfoWrapperPass)
INITIALIZE_PASS_DEPENDENCY(LegacyDivergenceAnalysis)
+INITIALIZE_PASS_DEPENDENCY(MemorySSAWrapperPass)
INITIALIZE_PASS_END(LoopUnswitch, "loop-unswitch", "Unswitch loops",
false, false)
LI = &getAnalysis<LoopInfoWrapperPass>().getLoopInfo();
LPM = &LPM_Ref;
DT = &getAnalysis<DominatorTreeWrapperPass>().getDomTree();
+ if (EnableMSSALoopDependency) {
+ MSSA = &getAnalysis<MemorySSAWrapperPass>().getMSSA();
+ MSSAU = make_unique<MemorySSAUpdater>(MSSA);
+ assert(DT && "Cannot update MemorySSA without a valid DomTree.");
+ }
currentLoop = L;
Function *F = currentLoop->getHeader()->getParent();
if (SanitizeMemory)
SafetyInfo.computeLoopSafetyInfo(L);
+ if (MSSA && VerifyMemorySSA)
+ MSSA->verifyMemorySSA();
+
bool Changed = false;
do {
assert(currentLoop->isLCSSAForm(*DT));
+ if (MSSA && VerifyMemorySSA)
+ MSSA->verifyMemorySSA();
redoLoop = false;
Changed |= processCurrentLoop();
} while(redoLoop);
+ if (MSSA && VerifyMemorySSA)
+ MSSA->verifyMemorySSA();
+
return Changed;
}
if (OldBranchSucc != TrueDest && OldBranchSucc != FalseDest) {
Updates.push_back({DominatorTree::Delete, OldBranchParent, OldBranchSucc});
}
-
DT->applyUpdates(Updates);
+
+ if (MSSAU)
+ MSSAU->applyUpdates(Updates, *DT);
}
// If either edge is critical, split it. This helps preserve LoopSimplify
// form for enclosing loops.
- auto Options = CriticalEdgeSplittingOptions(DT, LI).setPreserveLCSSA();
+ auto Options =
+ CriticalEdgeSplittingOptions(DT, LI, MSSAU.get()).setPreserveLCSSA();
SplitCriticalEdge(BI, 0, Options);
SplitCriticalEdge(BI, 1, Options);
}
// First step, split the preheader, so that we know that there is a safe place
// to insert the conditional branch. We will change loopPreheader to have a
// conditional branch on Cond.
- BasicBlock *NewPH = SplitEdge(loopPreheader, loopHeader, DT, LI);
+ BasicBlock *NewPH = SplitEdge(loopPreheader, loopHeader, DT, LI, MSSAU.get());
// Now that we have a place to insert the conditional branch, create a place
// to branch to: this is the exit block out of the loop that we should
// without actually branching to it (the exit block should be dominated by the
// loop header, not the preheader).
assert(!L->contains(ExitBlock) && "Exit block is in the loop?");
- BasicBlock *NewExit = SplitBlock(ExitBlock, &ExitBlock->front(), DT, LI);
+ BasicBlock *NewExit =
+ SplitBlock(ExitBlock, &ExitBlock->front(), DT, LI, MSSAU.get());
// Okay, now we have a position to branch from and a position to branch to,
// insert the new conditional branch.
// particular value, rewrite the loop with this info. We know that this will
// at least eliminate the old branch.
RewriteLoopBodyWithConditionConstant(L, Cond, Val, false);
+
++NumTrivial;
}
// Although SplitBlockPredecessors doesn't preserve loop-simplify in
// general, if we call it on all predecessors of all exits then it does.
- SplitBlockPredecessors(ExitBlock, Preds, ".us-lcssa", DT, LI, nullptr,
+ SplitBlockPredecessors(ExitBlock, Preds, ".us-lcssa", DT, LI, MSSAU.get(),
/*PreserveLCSSA*/ true);
}
}
// First step, split the preheader and exit blocks, and add these blocks to
// the LoopBlocks list.
- BasicBlock *NewPreheader = SplitEdge(loopPreheader, loopHeader, DT, LI);
+ BasicBlock *NewPreheader =
+ SplitEdge(loopPreheader, loopHeader, DT, LI, MSSAU.get());
LoopBlocks.push_back(NewPreheader);
// We want the loop to come after the preheader, but before the exit blocks.
assert(OldBR->isUnconditional() && OldBR->getSuccessor(0) == LoopBlocks[0] &&
"Preheader splitting did not work correctly!");
+ if (MSSAU) {
+ // Update MemorySSA after cloning, and before splitting to unreachables,
+ // since that invalidates the 1:1 mapping of clones in VMap.
+ LoopBlocksRPO LBRPO(L);
+ LBRPO.perform(LI);
+ MSSAU->updateForClonedLoop(LBRPO, ExitBlocks, VMap);
+ }
+
// Emit the new branch that selects between the two versions of this loop.
EmitPreheaderBranchOnCondition(LIC, Val, NewBlocks[0], LoopBlocks[0], OldBR,
TI);
LPM->deleteSimpleAnalysisValue(OldBR, L);
+ if (MSSAU) {
+ // Update MemoryPhis in Exit blocks.
+ MSSAU->updateExitBlocksForClonedLoop(ExitBlocks, VMap, *DT);
+ if (VerifyMemorySSA)
+ MSSA->verifyMemorySSA();
+ }
// The OldBr was replaced by a new one and removed (but not erased) by
// EmitPreheaderBranchOnCondition. It is no longer needed, so delete it.
if (!LoopProcessWorklist.empty() && LoopProcessWorklist.back() == NewLoop &&
LICHandle && !isa<Constant>(LICHandle))
RewriteLoopBodyWithConditionConstant(NewLoop, LICHandle, Val, true);
+
+ if (MSSA && VerifyMemorySSA)
+ MSSA->verifyMemorySSA();
}
/// Remove all instances of I from the worklist vector specified.
// and hooked up so as to preserve the loop structure, because
// trying to update it is complicated. So instead we preserve the
// loop structure and put the block on a dead code path.
- SplitEdge(Switch, SISucc, DT, LI);
+ SplitEdge(Switch, SISucc, DT, LI, MSSAU.get());
// Compute the successors instead of relying on the return value
// of SplitEdge, since it may have split the switch successor
// after PHI nodes.
Worklist.push_back(Use);
LPM->deleteSimpleAnalysisValue(I, L);
RemoveFromWorklist(I, Worklist);
+ if (MSSAU)
+ MSSAU->removeMemoryAccess(I);
I->eraseFromParent();
++NumSimplify;
continue;
// Move all of the successor contents from Succ to Pred.
Pred->getInstList().splice(BI->getIterator(), Succ->getInstList(),
Succ->begin(), Succ->end());
+ if (MSSAU)
+ MSSAU->moveAllAfterMergeBlocks(Succ, Pred, BI);
LPM->deleteSimpleAnalysisValue(BI, L);
RemoveFromWorklist(BI, Worklist);
BI->eraseFromParent();
projects / platform / upstream / llvm.git / commitdiff