Lower some min/max idioms to minss/maxss when unsafe fp math is enabled.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@30748 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Chris Lattner 2006-10-05 04:11:26 +00:00
parent 666ad1f8cf
commit 1907a7b37b

View File

@ -5377,25 +5377,55 @@ static SDOperand PerformSELECTCombine(SDNode *N, SelectionDAG &DAG,
unsigned IntNo = 0;
if (LHS == Cond.getOperand(0) && RHS == Cond.getOperand(1)) {
// (X olt Y) ? X : Y -> min
if (CC == ISD::SETOLT || CC == ISD::SETLT)
switch (CC) {
default: break;
case ISD::SETOLE: // (X <= Y) ? X : Y -> min
case ISD::SETULE:
case ISD::SETLE:
if (!UnsafeFPMath) break;
// FALL THROUGH.
case ISD::SETOLT: // (X olt/lt Y) ? X : Y -> min
case ISD::SETLT:
IntNo = LHS.getValueType() == MVT::f32 ? Intrinsic::x86_sse_min_ss :
Intrinsic::x86_sse2_min_sd;
// (X uge Y) ? X : Y -> max
if (CC == ISD::SETUGE || CC == ISD::SETGE)
break;
case ISD::SETOGT: // (X > Y) ? X : Y -> max
case ISD::SETUGT:
case ISD::SETGT:
if (!UnsafeFPMath) break;
// FALL THROUGH.
case ISD::SETUGE: // (X uge/ge Y) ? X : Y -> max
case ISD::SETGE:
IntNo = LHS.getValueType() == MVT::f32 ? Intrinsic::x86_sse_max_ss :
Intrinsic::x86_sse2_max_sd;
// TODO: Handle more cases if unsafe math!
Intrinsic::x86_sse2_max_sd;
break;
}
} else if (LHS == Cond.getOperand(1) && RHS == Cond.getOperand(0)) {
// (X uge Y) ? Y : X -> min
if (CC == ISD::SETUGE || CC == ISD::SETGE)
switch (CC) {
default: break;
case ISD::SETOGT: // (X > Y) ? Y : X -> min
case ISD::SETUGT:
case ISD::SETGT:
if (!UnsafeFPMath) break;
// FALL THROUGH.
case ISD::SETUGE: // (X uge/ge Y) ? Y : X -> min
case ISD::SETGE:
IntNo = LHS.getValueType() == MVT::f32 ? Intrinsic::x86_sse_min_ss :
Intrinsic::x86_sse2_min_sd;
// (X olt Y) ? Y : X -> max
if (CC == ISD::SETOLT || CC == ISD::SETLT)
Intrinsic::x86_sse2_min_sd;
break;
case ISD::SETOLE: // (X <= Y) ? Y : X -> max
case ISD::SETULE:
case ISD::SETLE:
if (!UnsafeFPMath) break;
// FALL THROUGH.
case ISD::SETOLT: // (X olt/lt Y) ? Y : X -> max
case ISD::SETLT:
IntNo = LHS.getValueType() == MVT::f32 ? Intrinsic::x86_sse_max_ss :
Intrinsic::x86_sse2_max_sd;
// TODO: Handle more cases if unsafe math!
Intrinsic::x86_sse2_max_sd;
break;
}
}
// minss/maxss take a v4f32 operand.