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authorDan Gohman <gohman@apple.com>2009-01-21 14:50:16 +0000
committerDan Gohman <gohman@apple.com>2009-01-21 14:50:16 +0000
commit1ef4d8f7ee60f724eff2175ed22f75a60eb8d50d (patch)
treef5deef088f589e4ace600983207a55229e16185d /lib
parent1421b7bc23f39e57052a51f4647512936f45b12f (diff)
Fix a recent regression. ClrOpcode is not set for i8; for i8, if
we want to clear %ah to zero before a division, just use a zero-extending mov to %al. This fixes PR3366. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62691 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'lib')
-rw-r--r--lib/Target/X86/X86ISelDAGToDAG.cpp5
1 files changed, 3 insertions, 2 deletions
diff --git a/lib/Target/X86/X86ISelDAGToDAG.cpp b/lib/Target/X86/X86ISelDAGToDAG.cpp
index 9b42d00b65..c1d886c32f 100644
--- a/lib/Target/X86/X86ISelDAGToDAG.cpp
+++ b/lib/Target/X86/X86ISelDAGToDAG.cpp
@@ -1381,9 +1381,10 @@ SDNode *X86DAGToDAGISel::Select(SDValue N) {
SDValue Tmp0, Tmp1, Tmp2, Tmp3;
bool foldedLoad = TryFoldLoad(N, N1, Tmp0, Tmp1, Tmp2, Tmp3);
+ bool signBitIsZero = CurDAG->SignBitIsZero(N0);
SDValue InFlag;
- if (NVT == MVT::i8 && !isSigned) {
+ if (NVT == MVT::i8 && (!isSigned || signBitIsZero)) {
// Special case for div8, just use a move with zero extension to AX to
// clear the upper 8 bits (AH).
SDValue Tmp0, Tmp1, Tmp2, Tmp3, Move, Chain;
@@ -1405,7 +1406,7 @@ SDNode *X86DAGToDAGISel::Select(SDValue N) {
InFlag =
CurDAG->getCopyToReg(CurDAG->getEntryNode(),
LoReg, N0, SDValue()).getValue(1);
- if (isSigned && !CurDAG->SignBitIsZero(N0)) {
+ if (isSigned && !signBitIsZero) {
// Sign extend the low part into the high part.
InFlag =
SDValue(CurDAG->getTargetNode(SExtOpcode, MVT::Flag, InFlag), 0);