diff options
Diffstat (limited to 'llvm/lib/Transforms')
| -rw-r--r-- | llvm/lib/Transforms/Scalar/NewGVN.cpp | 4 |
1 files changed, 4 insertions, 0 deletions
diff --git a/llvm/lib/Transforms/Scalar/NewGVN.cpp b/llvm/lib/Transforms/Scalar/NewGVN.cpp index c7afd1d80ed..e976f0ec8c3 100644 --- a/llvm/lib/Transforms/Scalar/NewGVN.cpp +++ b/llvm/lib/Transforms/Scalar/NewGVN.cpp @@ -734,6 +734,10 @@ PHIExpression *NewGVN::createPHIExpression(Instruction *I, bool &HasBackedge, // PHIs. LLVM doesn't seem to always guarantee this. While we need to fix // this in LLVM at some point we don't want GVN to find wrong congruences. // Therefore, here we sort uses in predecessor order. + // We're sorting the values by pointer. In theory this might be cause of + // non-determinism, but here we don't rely on the ordering for anything + // significant, e.g. we don't create new instructions based on it so we're + // fine. SmallVector<const Use *, 4> PHIOperands; for (const Use &U : PN->operands()) PHIOperands.push_back(&U); |
