diff options
Diffstat (limited to 'lib')
| -rw-r--r-- | lib/Transforms/Scalar/IndVarSimplify.cpp | 11 |
1 files changed, 8 insertions, 3 deletions
diff --git a/lib/Transforms/Scalar/IndVarSimplify.cpp b/lib/Transforms/Scalar/IndVarSimplify.cpp index 2a3e4725a1..00f8831eb2 100644 --- a/lib/Transforms/Scalar/IndVarSimplify.cpp +++ b/lib/Transforms/Scalar/IndVarSimplify.cpp @@ -1015,9 +1015,9 @@ bool IndVarSimplify::EliminateIVUser(Instruction *UseInst, (SE->getSCEV(UseInst) != SE->getSCEV(IVOperand))) return false; - UseInst->replaceAllUsesWith(IVOperand); - DEBUG(dbgs() << "INDVARS: Eliminated identity: " << *UseInst << '\n'); + + UseInst->replaceAllUsesWith(IVOperand); ++NumElimIdentity; Changed = true; DeadInsts.push_back(UseInst); @@ -1037,7 +1037,9 @@ static void pushIVUsers( // Avoid infinite or exponential worklist processing. // Also ensure unique worklist users. - if (Simplified.insert(User)) + // If Def is a LoopPhi, it may not be in the Simplified set, so check for + // self edges first. + if (User != Def && Simplified.insert(User)) SimpleIVUsers.push_back(std::make_pair(User, Def)); } } @@ -1111,6 +1113,9 @@ void IndVarSimplify::SimplifyIVUsersNoRewrite(Loop *L, SCEVExpander &Rewriter) { // Use-def pairs if IVUsers waiting to be processed for CurrIV. SmallVector<std::pair<Instruction*, Instruction*>, 8> SimpleIVUsers; + // Push users of the current LoopPhi. In rare cases, pushIVUsers may be + // called multiple times for the same LoopPhi. This is the proper thing to + // do for loop header phis that use each other. pushIVUsers(CurrIV, Simplified, SimpleIVUsers); while (!SimpleIVUsers.empty()) { |