From d102a03b36fb522899cefc31a396c9793b929cf6 Mon Sep 17 00:00:00 2001 From: Eli Friedman Date: Thu, 22 Sep 2011 18:56:30 +0000 Subject: PR10987: add a missed safety check to isSafePHIToSpeculate in scalarrepl. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@140327 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Transforms/Scalar/ScalarReplAggregates.cpp | 18 +++++++++++------- 1 file changed, 11 insertions(+), 7 deletions(-) (limited to 'lib/Transforms/Scalar/ScalarReplAggregates.cpp') diff --git a/lib/Transforms/Scalar/ScalarReplAggregates.cpp b/lib/Transforms/Scalar/ScalarReplAggregates.cpp index 3721807933..82364c36e4 100644 --- a/lib/Transforms/Scalar/ScalarReplAggregates.cpp +++ b/lib/Transforms/Scalar/ScalarReplAggregates.cpp @@ -1286,17 +1286,21 @@ static bool isSafePHIToSpeculate(PHINode *PN, const TargetData *TD) { // trapping load in the predecessor if it is a critical edge. for (unsigned i = 0, e = PN->getNumIncomingValues(); i != e; ++i) { BasicBlock *Pred = PN->getIncomingBlock(i); + Value *InVal = PN->getIncomingValue(i); + + // If the terminator of the predecessor has side-effects (an invoke), + // there is no safe place to put a load in the predecessor. + if (Pred->getTerminator()->mayHaveSideEffects()) + return false; + + // If the value is produced by the terminator of the predecessor + // (an invoke), there is no valid place to put a load in the predecessor. + if (Pred->getTerminator() == InVal) + return false; // If the predecessor has a single successor, then the edge isn't critical. if (Pred->getTerminator()->getNumSuccessors() == 1) continue; - - Value *InVal = PN->getIncomingValue(i); - - // If the InVal is an invoke in the pred, we can't put a load on the edge. - if (InvokeInst *II = dyn_cast(InVal)) - if (II->getParent() == Pred) - return false; // If this pointer is always safe to load, or if we can prove that there is // already a load in the block, then we can move the load to the pred block. -- cgit v1.2.3