diff options
Diffstat (limited to 'lib/Target/X86/InstSelectSimple.cpp')
| -rw-r--r-- | lib/Target/X86/InstSelectSimple.cpp | 13 |
1 files changed, 11 insertions, 2 deletions
diff --git a/lib/Target/X86/InstSelectSimple.cpp b/lib/Target/X86/InstSelectSimple.cpp index 6144b626a6..d44288678c 100644 --- a/lib/Target/X86/InstSelectSimple.cpp +++ b/lib/Target/X86/InstSelectSimple.cpp @@ -1690,14 +1690,23 @@ void ISel::emitSimpleBinaryOperation(MachineBasicBlock *MBB, unsigned Class = getClassB(Op0->getType()); // sub 0, X -> neg X - if (OperatorClass == 1 && Class != cLong) + if (OperatorClass == 1) if (ConstantInt *CI = dyn_cast<ConstantInt>(Op0)) { if (CI->isNullValue()) { unsigned op1Reg = getReg(Op1, MBB, IP); static unsigned const NEGTab[] = { - X86::NEG8r, X86::NEG16r, X86::NEG32r + X86::NEG8r, X86::NEG16r, X86::NEG32r, 0, X86::NEG32r }; BuildMI(*MBB, IP, NEGTab[Class], 1, DestReg).addReg(op1Reg); + + if (Class == cLong) { + // We just emitted: Dl = neg Sl + // Now emit : T = addc Sh, 0 + // : Dh = neg T + unsigned T = makeAnotherReg(Type::IntTy); + BuildMI(*MBB, IP, X86::ADC32ri, 2, T).addReg(op1Reg+1).addImm(0); + BuildMI(*MBB, IP, X86::NEG32r, 1, DestReg+1).addReg(T); + } return; } } else if (ConstantFP *CFP = dyn_cast<ConstantFP>(Op0)) |