// Try to match this select into a max/min operation, which have dedicated
// opcode in the instruction set.
- // NOTE: This is not correct in the presence of NaNs, so we only enable this
+ // FIXME: This is not correct in the presence of NaNs, so we only enable this
// in no-NaNs mode.
if (getTargetMachine().Options.NoNaNsFPMath) {
- if (selectCCOpsAreFMaxCompatible(LHS, FVal) &&
- selectCCOpsAreFMaxCompatible(RHS, TVal)) {
+ SDValue MinMaxLHS = TVal, MinMaxRHS = FVal;
+ if (selectCCOpsAreFMaxCompatible(LHS, MinMaxRHS) &&
+ selectCCOpsAreFMaxCompatible(RHS, MinMaxLHS)) {
CC = ISD::getSetCCSwappedOperands(CC);
- std::swap(TVal, FVal);
+ std::swap(MinMaxLHS, MinMaxRHS);
}
- if (selectCCOpsAreFMaxCompatible(LHS, TVal) &&
- selectCCOpsAreFMaxCompatible(RHS, FVal)) {
+ if (selectCCOpsAreFMaxCompatible(LHS, MinMaxLHS) &&
+ selectCCOpsAreFMaxCompatible(RHS, MinMaxRHS)) {
switch (CC) {
default:
break;
case ISD::SETUGE:
case ISD::SETOGT:
case ISD::SETOGE:
- return DAG.getNode(ARM64ISD::FMAX, dl, VT, TVal, FVal);
+ return DAG.getNode(ARM64ISD::FMAX, dl, VT, MinMaxLHS, MinMaxRHS);
break;
case ISD::SETLT:
case ISD::SETLE:
case ISD::SETULE:
case ISD::SETOLT:
case ISD::SETOLE:
- return DAG.getNode(ARM64ISD::FMIN, dl, VT, TVal, FVal);
+ return DAG.getNode(ARM64ISD::FMIN, dl, VT, MinMaxLHS, MinMaxRHS);
break;
}
}
; RUN: llc -march=arm64 -enable-no-nans-fp-math < %s | FileCheck %s
define double @test_direct(float %in) #1 {
-entry:
+; CHECK-LABEL: test_direct:
%cmp = fcmp olt float %in, 0.000000e+00
%longer = fpext float %in to double
%val = select i1 %cmp, double 0.000000e+00, double %longer
}
define double @test_cross(float %in) #1 {
-entry:
+; CHECK-LABEL: test_cross:
%cmp = fcmp olt float %in, 0.000000e+00
%longer = fpext float %in to double
%val = select i1 %cmp, double %longer, double 0.000000e+00
; CHECK: fmin
}
+
+; This isn't a min or a max, but passes the first condition for swapping the
+; results. Make sure they're put back before we resort to the normal fcsel.
+define float @test_cross_fail(float %lhs, float %rhs) {
+; CHECK-LABEL: test_cross_fail:
+ %tst = fcmp une float %lhs, %rhs
+ %res = select i1 %tst, float %rhs, float %lhs
+ ret float %res
+
+ ; The register allocator would have to decide to be deliberately obtuse before
+ ; other register were used.
+; CHECK: fcsel s0, s1, s0, ne
+}
\ No newline at end of file