Turn X < 0 -> TEST X,X js
llvm-svn: 30294
diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp
index 56ee57e..dfd7aa5 100644
--- a/llvm/lib/Target/X86/X86ISelLowering.cpp
+++ b/llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -1873,14 +1873,17 @@
SelectionDAG &DAG) {
X86CC = X86ISD::COND_INVALID;
if (!isFP) {
- if (SetCCOpcode == ISD::SETGT) {
- if (ConstantSDNode *RHSC = dyn_cast<ConstantSDNode>(RHS))
- if (RHSC->isAllOnesValue()) {
- // X > -1 -> X == 0, jump on sign.
- RHS = DAG.getConstant(0, RHS.getValueType());
- X86CC = X86ISD::COND_NS;
- return true;
- }
+ if (ConstantSDNode *RHSC = dyn_cast<ConstantSDNode>(RHS)) {
+ if (SetCCOpcode == ISD::SETGT && RHSC->isAllOnesValue()) {
+ // X > -1 -> X == 0, jump !sign.
+ RHS = DAG.getConstant(0, RHS.getValueType());
+ X86CC = X86ISD::COND_NS;
+ return true;
+ } else if (SetCCOpcode == ISD::SETLT && RHSC->isNullValue()) {
+ // X < 0 -> X == 0, jump on sign.
+ X86CC = X86ISD::COND_S;
+ return true;
+ }
}
switch (SetCCOpcode) {