From 58a37754bb107ee1bd2e7a94f1da39fcebe900d9 Mon Sep 17 00:00:00 2001 From: Alina Sbirlea Date: Wed, 10 Jul 2019 17:36:56 +0000 Subject: [LoopRotate + MemorySSA] Keep an map. Summary: The map kept in loop rotate is used for instruction remapping, in order to simplify the clones of instructions. Thus, if an instruction can be simplified, its simplified value is placed in the map, even when the clone is added to the IR. MemorySSA in contrast needs to know about that clone, so it can add an access for it. To resolve this: keep a different map for MemorySSA. Reviewers: george.burgess.iv Subscribers: jlebar, Prazek, llvm-commits Tags: #llvm Differential Revision: https://reviews.llvm.org/D63680 llvm-svn: 365672 --- llvm/lib/Transforms/Utils/LoopRotationUtils.cpp | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) (limited to 'llvm/lib/Transforms/Utils/LoopRotationUtils.cpp') diff --git a/llvm/lib/Transforms/Utils/LoopRotationUtils.cpp b/llvm/lib/Transforms/Utils/LoopRotationUtils.cpp index 88c4937cfe1..37389a695b4 100644 --- a/llvm/lib/Transforms/Utils/LoopRotationUtils.cpp +++ b/llvm/lib/Transforms/Utils/LoopRotationUtils.cpp @@ -295,7 +295,7 @@ bool LoopRotate::rotateLoop(Loop *L, bool SimplifiedLatch) { // Begin by walking OrigHeader and populating ValueMap with an entry for // each Instruction. BasicBlock::iterator I = OrigHeader->begin(), E = OrigHeader->end(); - ValueToValueMapTy ValueMap; + ValueToValueMapTy ValueMap, ValueMapMSSA; // For PHI nodes, the value available in OldPreHeader is just the // incoming value from OldPreHeader. @@ -374,6 +374,9 @@ bool LoopRotate::rotateLoop(Loop *L, bool SimplifiedLatch) { if (auto *II = dyn_cast(C)) if (II->getIntrinsicID() == Intrinsic::assume) AC->registerAssumption(II); + // MemorySSA cares whether the cloned instruction was inserted or not, and + // not whether it can be remapped to a simplified value. + ValueMapMSSA[Inst] = C; } } @@ -391,10 +394,11 @@ bool LoopRotate::rotateLoop(Loop *L, bool SimplifiedLatch) { LoopEntryBranch->eraseFromParent(); // Update MemorySSA before the rewrite call below changes the 1:1 - // instruction:cloned_instruction_or_value mapping in ValueMap. + // instruction:cloned_instruction_or_value mapping. if (MSSAU) { - ValueMap[OrigHeader] = OrigPreheader; - MSSAU->updateForClonedBlockIntoPred(OrigHeader, OrigPreheader, ValueMap); + ValueMapMSSA[OrigHeader] = OrigPreheader; + MSSAU->updateForClonedBlockIntoPred(OrigHeader, OrigPreheader, + ValueMapMSSA); } SmallVector InsertedPHIs; -- cgit v1.2.3