From dfd358f597cea078061476991bfeea06b9c3a7d4 Mon Sep 17 00:00:00 2001 From: Justin Lebar Date: Wed, 13 Jul 2016 22:34:50 +0000 Subject: [MI] Fix MachineInstr::isInvariantLoad. Summary: Previously it would say we had an invariant load if any of the memory operands were invariant. But the load should be invariant only if *all* the memory operands are invariant. No testcase because this has proven to be very difficult to tickle in practice. As just one example, ARM's ldrd instruction, which loads 64 bits into two 32-bit regs, is theoretically affected by this. But when it's produced, it loses its memoperands' invariance bits! Reviewers: jfb Subscribers: llvm-commits, aemerson Differential Revision: http://reviews.llvm.org/D22318 llvm-svn: 275331 --- llvm/lib/CodeGen/MachineInstr.cpp | 3 +-- 1 file changed, 1 insertion(+), 2 deletions(-) (limited to 'llvm/lib/CodeGen/MachineInstr.cpp') diff --git a/llvm/lib/CodeGen/MachineInstr.cpp b/llvm/lib/CodeGen/MachineInstr.cpp index 0b55d2e0b43..0b107c0abe5 100644 --- a/llvm/lib/CodeGen/MachineInstr.cpp +++ b/llvm/lib/CodeGen/MachineInstr.cpp @@ -1585,8 +1585,7 @@ bool MachineInstr::isInvariantLoad(AliasAnalysis *AA) const { E = memoperands_end(); I != E; ++I) { if ((*I)->isVolatile()) return false; if ((*I)->isStore()) return false; - if ((*I)->isInvariant()) return true; - + if ((*I)->isInvariant()) continue; // A load from a constant PseudoSourceValue is invariant. if (const PseudoSourceValue *PSV = (*I)->getPseudoValue()) -- cgit v1.2.3