aboutsummaryrefslogtreecommitdiffstats
path: root/lib
diff options
context:
space:
mode:
authorEli Friedman <eli.friedman@gmail.com>2008-06-13 22:02:12 +0000
committerEli Friedman <eli.friedman@gmail.com>2008-06-13 22:02:12 +0000
commit3a311d57abc4ffc2e5bcbcd64e247f264c7a9a17 (patch)
tree25392f38f7effd961eacdff4946754d73a7cbac4 /lib
parent87bc2f19f8d72a9a5ea25bf711fba75baafe8562 (diff)
downloadexternal_llvm-3a311d57abc4ffc2e5bcbcd64e247f264c7a9a17.zip
external_llvm-3a311d57abc4ffc2e5bcbcd64e247f264c7a9a17.tar.gz
external_llvm-3a311d57abc4ffc2e5bcbcd64e247f264c7a9a17.tar.bz2
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
Diffstat (limited to 'lib')
-rw-r--r--lib/Transforms/Scalar/InstructionCombining.cpp11
1 files changed, 6 insertions, 5 deletions
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<LoadInst>(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<LoadInst>(I) || I->mayWriteToMemory())
+ if (I->mayReadFromMemory() || I->mayWriteToMemory())
return false;
}
}