search for: build_in

This seems a very natural approach but I probably am having a trouble with the iterator invalidation. However, looking at other peephole optimizers passes, I couldn't see how to do this: #define BUILD_INS(opcode, new_reg, i) \ BuildMI(*MBB, MBBI, MBBI->getDebugLoc(), TII->get(X86::opcode)) \ .addReg(X86::new_reg, kill).addImm(i) for (MachineFunction::iterator MFI = MF.begin(), MFE = MF.end(); MFI != MFE; ++MFI) { MachineBasicBlock* MBB = MFI...

I'm writing a peephole pass and I'm done with the X86_64 instruction level detail work. But I'm having difficulty with the basic block surgery of replacing the old MachineInst. The peephole pass gets called per MachineFunction and then iterates over each MachineBasicBlock and in turn over each MachineInst. When it finds an instruction which should be replaced, it builds a new

I made the change to the BuildMI() call. Again, I don't think that matters. #define BUILD_INS(opcode, new_reg, i) \ BuildMI(*MBB, OldMI, MBBI->getDebugLoc(), TII->get(X86::opcode)) \ .addReg(X86::new_reg, kill).addImm(i) I didn't completely understand your other proposed change: ​ for (MachineBasicBlock::iterator MBBI = MBB->begin();...

There are 11 BuildMI() functions in MachineInstrBuilder.h including four using the iterator and one using an instruction. But I just don't think that's it. The creation of the new instruction works fine (works fine with OldMI as well) and the new instruction is present in the assembly output. The problem is removing the old instruction correctly. > The loop header needs to be