search for: op0reg

...t; vregs: this is what the instruction selector is about. I recommend taking a look at the getReg(*) methods in the X86 instruction selector. The basic code generation stage for an add, boiled down to its simplest form, basically looks like this: void visitAdd(BinaryOperator &B) { unsigned Op0Reg = getReg(B.getOperand(0)); unsigned Op1Reg = getReg(B.getOperand(1)); unsigned DestReg = getReg(B); unsigned Opcode = (get the opcode for the size of the add); BuildMI(<where>, Opcode, 2, DestReg).addReg(Op0Reg).addReg(Op1Reg); } The nice thing about the "getReg" functiona...

Ok, I'm now trying to write instruction selector and have some questions 1. The MachineInstrBuilder has methods to add register operand and immediate operand. However, what would be really nice is a method to add Value*. So, I would write: BuildMI(*BB, NM::add, 1).add(I.getOperand(0), I.getOperand(1)); and depending on whether the passed Value* is contant or instruction, the add

...> selector is about. > > I recommend taking a look at the getReg(*) methods in the X86 instruction > selector. The basic code generation stage for an add, boiled down to its > simplest form, basically looks like this: > > void visitAdd(BinaryOperator &B) { > unsigned Op0Reg = getReg(B.getOperand(0)); > unsigned Op1Reg = getReg(B.getOperand(1)); > unsigned DestReg = getReg(B); > > unsigned Opcode = (get the opcode for the size of the add); > BuildMI(<where>, Opcode, 2, DestReg).addReg(Op0Reg).addReg(Op1Reg); > } > > The nice thing...