From 6903a24f32e11d10ad7232b2c16c8d07f27a31c7 Mon Sep 17 00:00:00 2001 From: Eli Friedman Date: Fri, 13 Jun 2008 22:02:12 +0000 Subject: Don't skip over instructions other than loads that might read memory when trying to sink stores. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@52259 91177308-0d34-0410-b5e6-96231b3b80d8 --- lib/Transforms/Scalar/InstructionCombining.cpp | 11 ++++++----- 1 file changed, 6 insertions(+), 5 deletions(-) (limited to 'lib') diff --git a/lib/Transforms/Scalar/InstructionCombining.cpp b/lib/Transforms/Scalar/InstructionCombining.cpp index 8dbca0f..8a7128b 100644 --- a/lib/Transforms/Scalar/InstructionCombining.cpp +++ b/lib/Transforms/Scalar/InstructionCombining.cpp @@ -10417,18 +10417,19 @@ bool InstCombiner::SimplifyStoreAtEndOfBlock(StoreInst &SI) { return false; break; } - // If we find something that may be using the stored value, or if we run - // out of instructions, we can't do the xform. - if (isa(BBI) || BBI->mayWriteToMemory() || + // If we find something that may be using or overwriting the stored + // value, or if we run out of instructions, we can't do the xform. + if (BBI->mayReadFromMemory() || BBI->mayWriteToMemory() || BBI == OtherBB->begin()) return false; } // In order to eliminate the store in OtherBr, we have to - // make sure nothing reads the stored value in StoreBB. + // make sure nothing reads or overwrites the stored value in + // StoreBB. for (BasicBlock::iterator I = StoreBB->begin(); &*I != &SI; ++I) { // FIXME: This should really be AA driven. - if (isa(I) || I->mayWriteToMemory()) + if (I->mayReadFromMemory() || I->mayWriteToMemory()) return false; } } -- cgit v1.1