diff --git a/lib/Target/X86/X86ISelSimple.cpp b/lib/Target/X86/X86ISelSimple.cpp index 5e6fd2fbd2d..4aeab3e5184 100644 --- a/lib/Target/X86/X86ISelSimple.cpp +++ b/lib/Target/X86/X86ISelSimple.cpp @@ -560,8 +560,15 @@ void X86ISel::copyConstantToRegister(MachineBasicBlock *MBB, BuildMI(*MBB, IP, X86::FLD0, 0, R); else if (CFP->isExactlyValue(+1.0)) BuildMI(*MBB, IP, X86::FLD1, 0, R); - else { // FIXME: PI, other native values - // FIXME: Could handle -1.0 with FLD1/FCHS + else if (CFP->isExactlyValue(-0.0)) { + unsigned Tmp = makeAnotherReg(Type::DoubleTy); + BuildMI(*MBB, IP, X86::FLD0, 0, Tmp); + BuildMI(*MBB, IP, X86::FCHS, 1, R).addReg(Tmp); + } else if (CFP->isExactlyValue(-1.0)) { + unsigned Tmp = makeAnotherReg(Type::DoubleTy); + BuildMI(*MBB, IP, X86::FLD1, 0, Tmp); + BuildMI(*MBB, IP, X86::FCHS, 1, R).addReg(Tmp); + } else { // FIXME: PI, other native values // FIXME: 2*PI -> LDPI + FADD // Otherwise we need to spill the constant to memory.