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Diffstat (limited to 'lib/Target/X86/X86ISelLowering.cpp')
-rw-r--r--lib/Target/X86/X86ISelLowering.cpp40
1 files changed, 0 insertions, 40 deletions
diff --git a/lib/Target/X86/X86ISelLowering.cpp b/lib/Target/X86/X86ISelLowering.cpp
index 9ff05a2d11..1580935fb2 100644
--- a/lib/Target/X86/X86ISelLowering.cpp
+++ b/lib/Target/X86/X86ISelLowering.cpp
@@ -14415,7 +14415,6 @@ static SDValue PerformCMOVCombine(SDNode *N, SelectionDAG &DAG,
if (TrueC->getAPIntValue().ult(FalseC->getAPIntValue())) {
CC = X86::GetOppositeBranchCondition(CC);
std::swap(TrueC, FalseC);
- std::swap(TrueOp, FalseOp);
}
// Optimize C ? 8 : 0 -> zext(setcc(C)) << 3. Likewise for any pow2/0.
@@ -14498,45 +14497,6 @@ static SDValue PerformCMOVCombine(SDNode *N, SelectionDAG &DAG,
}
}
}
-
- // Handle these cases:
- // (select (x != c), e, c) -> select (x != c), e, x),
- // (select (x == c), c, e) -> select (x == c), x, e)
- // where the c is an integer constant, and the "select" is the combination
- // of CMOV and CMP.
- //
- // The rationale for this change is that the conditional-move from a constant
- // needs two instructions, however, conditional-move from a register needs
- // only one instruction.
- //
- // CAVEAT: By replacing a constant with a symbolic value, it may obscure
- // some instruction-combining opportunities. This opt needs to be
- // postponed as late as possible.
- //
- if (!DCI.isBeforeLegalize() && !DCI.isBeforeLegalizeOps()) {
- // the DCI.xxxx conditions are provided to postpone the optimization as
- // late as possible.
-
- ConstantSDNode *CmpAgainst = 0;
- if ((Cond.getOpcode() == X86ISD::CMP || Cond.getOpcode() == X86ISD::SUB) &&
- (CmpAgainst = dyn_cast<ConstantSDNode>(Cond.getOperand(1))) &&
- dyn_cast<ConstantSDNode>(Cond.getOperand(0)) == 0) {
-
- if (CC == X86::COND_NE &&
- CmpAgainst == dyn_cast<ConstantSDNode>(FalseOp)) {
- CC = X86::GetOppositeBranchCondition(CC);
- std::swap(TrueOp, FalseOp);
- }
-
- if (CC == X86::COND_E &&
- CmpAgainst == dyn_cast<ConstantSDNode>(TrueOp)) {
- SDValue Ops[] = { FalseOp, Cond.getOperand(0), N->getOperand(2), Cond };
- return DAG.getNode(X86ISD::CMOV, DL, N->getVTList (), Ops,
- array_lengthof(Ops));
- }
- }
- }
-
return SDValue();
}