From 3cd6a61b275f49df4f2aaa273efbf4cf8e0a6511 Mon Sep 17 00:00:00 2001 From: Chris Lattner Date: Mon, 2 Nov 2009 02:06:37 +0000 Subject: fix instcombine to only do store sinking when the alignments of the two loads agree. Propagate that onto the new store. llvm-svn: 85772 --- llvm/lib/Transforms/Scalar/InstructionCombining.cpp | 12 ++++++++---- 1 file changed, 8 insertions(+), 4 deletions(-) (limited to 'llvm/lib') diff --git a/llvm/lib/Transforms/Scalar/InstructionCombining.cpp b/llvm/lib/Transforms/Scalar/InstructionCombining.cpp index 07681d15d87..ba899bf15bb 100644 --- a/llvm/lib/Transforms/Scalar/InstructionCombining.cpp +++ b/llvm/lib/Transforms/Scalar/InstructionCombining.cpp @@ -11943,9 +11943,11 @@ bool InstCombiner::SimplifyStoreAtEndOfBlock(StoreInst &SI) { return false; --BBI; } - // If this isn't a store, or isn't a store to the same location, bail out. + // If this isn't a store, isn't a store to the same location, or if the + // alignments differ, bail out. OtherStore = dyn_cast(BBI); - if (!OtherStore || OtherStore->getOperand(1) != SI.getOperand(1)) + if (!OtherStore || OtherStore->getOperand(1) != SI.getOperand(1) || + OtherStore->getAlignment() != SI.getAlignment()) return false; } else { // Otherwise, the other block ended with a conditional branch. If one of the @@ -11960,7 +11962,8 @@ bool InstCombiner::SimplifyStoreAtEndOfBlock(StoreInst &SI) { for (;; --BBI) { // Check to see if we find the matching store. if ((OtherStore = dyn_cast(BBI))) { - if (OtherStore->getOperand(1) != SI.getOperand(1)) + if (OtherStore->getOperand(1) != SI.getOperand(1) || + OtherStore->getAlignment() != SI.getAlignment()) return false; break; } @@ -11995,7 +11998,8 @@ bool InstCombiner::SimplifyStoreAtEndOfBlock(StoreInst &SI) { // insert it. BBI = DestBB->getFirstNonPHI(); InsertNewInstBefore(new StoreInst(MergedVal, SI.getOperand(1), - OtherStore->isVolatile()), *BBI); + OtherStore->isVolatile(), + SI.getAlignment()), *BBI); // Nuke the old stores. EraseInstFromFunction(SI); -- cgit v1.2.3