diff options
| -rw-r--r-- | lib/Transforms/Scalar/Sink.cpp | 13 | ||||
| -rw-r--r-- | test/Transforms/Sink/basic.ll | 16 |
2 files changed, 22 insertions, 7 deletions
diff --git a/lib/Transforms/Scalar/Sink.cpp b/lib/Transforms/Scalar/Sink.cpp index 705f442049..c83f56c4d2 100644 --- a/lib/Transforms/Scalar/Sink.cpp +++ b/lib/Transforms/Scalar/Sink.cpp @@ -153,9 +153,13 @@ bool Sinking::ProcessBlock(BasicBlock &BB) { static bool isSafeToMove(Instruction *Inst, AliasAnalysis *AA, SmallPtrSet<Instruction *, 8> &Stores) { - if (LoadInst *L = dyn_cast<LoadInst>(Inst)) { - if (L->isVolatile()) return false; + if (Inst->mayWriteToMemory()) { + Stores.insert(Inst); + return false; + } + + if (LoadInst *L = dyn_cast<LoadInst>(Inst)) { AliasAnalysis::Location Loc = AA->getLocation(L); for (SmallPtrSet<Instruction *, 8>::iterator I = Stores.begin(), E = Stores.end(); I != E; ++I) @@ -163,11 +167,6 @@ static bool isSafeToMove(Instruction *Inst, AliasAnalysis *AA, return false; } - if (Inst->mayWriteToMemory()) { - Stores.insert(Inst); - return false; - } - if (isa<TerminatorInst>(Inst) || isa<PHINode>(Inst)) return false; diff --git a/test/Transforms/Sink/basic.ll b/test/Transforms/Sink/basic.ll index 54b7f1369d..81782e9d42 100644 --- a/test/Transforms/Sink/basic.ll +++ b/test/Transforms/Sink/basic.ll @@ -20,3 +20,19 @@ true: false: ret i32 0 } + +; But don't sink volatile loads... + +; CHECK: @foo2 +; CHECK: volatile load +; CHECK-NEXT: store i32 + +define i32 @foo2(i1 %z) { + %l = volatile load i32* @A + store i32 0, i32* @B + br i1 %z, label %true, label %false +true: + ret i32 %l +false: + ret i32 0 +} |