diff options
Diffstat (limited to 'contrib/llvm/lib/Transforms/Utils/LCSSA.cpp')
| -rw-r--r-- | contrib/llvm/lib/Transforms/Utils/LCSSA.cpp | 15 |
1 files changed, 14 insertions, 1 deletions
diff --git a/contrib/llvm/lib/Transforms/Utils/LCSSA.cpp b/contrib/llvm/lib/Transforms/Utils/LCSSA.cpp index b654111..5e05c83 100644 --- a/contrib/llvm/lib/Transforms/Utils/LCSSA.cpp +++ b/contrib/llvm/lib/Transforms/Utils/LCSSA.cpp @@ -53,6 +53,8 @@ namespace { // Cached analysis information for the current function. DominatorTree *DT; + LoopInfo *LI; + ScalarEvolution *SE; std::vector<BasicBlock*> LoopBlocks; PredIteratorCache PredCache; Loop *L; @@ -117,6 +119,8 @@ bool LCSSA::runOnLoop(Loop *TheLoop, LPPassManager &LPM) { L = TheLoop; DT = &getAnalysis<DominatorTree>(); + LI = &getAnalysis<LoopInfo>(); + SE = getAnalysisIfAvailable<ScalarEvolution>(); // Get the set of exiting blocks. SmallVector<BasicBlock*, 8> ExitBlocks; @@ -156,6 +160,12 @@ bool LCSSA::runOnLoop(Loop *TheLoop, LPPassManager &LPM) { MadeChange |= ProcessInstruction(I, ExitBlocks); } } + + // If we modified the code, remove any caches about the loop from SCEV to + // avoid dangling entries. + // FIXME: This is a big hammer, can we clear the cache more selectively? + if (SE && MadeChange) + SE->forgetLoop(L); assert(L->isLCSSAForm(*DT)); PredCache.clear(); @@ -245,7 +255,7 @@ bool LCSSA::ProcessInstruction(Instruction *Inst, // Remember that this phi makes the value alive in this block. SSAUpdate.AddAvailableValue(ExitBB, PN); } - + // Rewrite all uses outside the loop in terms of the new PHIs we just // inserted. for (unsigned i = 0, e = UsesToRewrite.size(); i != e; ++i) { @@ -260,6 +270,9 @@ bool LCSSA::ProcessInstruction(Instruction *Inst, if (isa<PHINode>(UserBB->begin()) && isExitBlock(UserBB, ExitBlocks)) { + // Tell the VHs that the uses changed. This updates SCEV's caches. + if (UsesToRewrite[i]->get()->hasValueHandle()) + ValueHandleBase::ValueIsRAUWd(*UsesToRewrite[i], UserBB->begin()); UsesToRewrite[i]->set(UserBB->begin()); continue; } |
