fix instcombine to only do store sinking when the alignments

of the two loads agree.  Propagate that onto the new store.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@85772 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner
2009-11-02 02:06:37 +00:00
parent f013eea972
commit 7ebbabf500
2 changed files with 26 additions and 4 deletions

View File

@@ -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<StoreInst>(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<StoreInst>(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);