llvm-6502/lib/Target/X86/X86InstrInfo.cpp

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//===- X86InstrInfo.cpp - X86 Instruction Information -----------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file was developed by the LLVM research group and is distributed under
// the University of Illinois Open Source License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains the X86 implementation of the TargetInstrInfo class.
//
//===----------------------------------------------------------------------===//
#include "X86InstrInfo.h"
#include "X86.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "X86GenInstrInfo.inc"
using namespace llvm;
X86InstrInfo::X86InstrInfo()
: TargetInstrInfo(X86Insts, sizeof(X86Insts)/sizeof(X86Insts[0])) {
}
bool X86InstrInfo::isMoveInstr(const MachineInstr& MI,
unsigned& sourceReg,
unsigned& destReg) const {
MachineOpCode oc = MI.getOpcode();
if (oc == X86::MOV8rr || oc == X86::MOV16rr || oc == X86::MOV32rr ||
oc == X86::FpMOV) {
assert(MI.getNumOperands() == 2 &&
MI.getOperand(0).isRegister() &&
MI.getOperand(1).isRegister() &&
"invalid register-register move instruction");
sourceReg = MI.getOperand(1).getReg();
destReg = MI.getOperand(0).getReg();
return true;
}
return false;
}
void X86InstrInfo::insertGoto(MachineBasicBlock& MBB,
MachineBasicBlock& TMBB) const {
BuildMI(MBB, MBB.end(), X86::JMP, 1).addMBB(&TMBB);
}
MachineBasicBlock::iterator
X86InstrInfo::reverseBranchCondition(MachineBasicBlock::iterator MI) const {
unsigned Opcode = MI->getOpcode();
assert(isBranch(Opcode) && "MachineInstr must be a branch");
unsigned ROpcode;
switch (Opcode) {
default: assert(0 && "Cannot reverse unconditional branches!");
case X86::JB: ROpcode = X86::JAE; break;
case X86::JAE: ROpcode = X86::JB; break;
case X86::JE: ROpcode = X86::JNE; break;
case X86::JNE: ROpcode = X86::JE; break;
case X86::JBE: ROpcode = X86::JA; break;
case X86::JA: ROpcode = X86::JBE; break;
case X86::JS: ROpcode = X86::JNS; break;
case X86::JNS: ROpcode = X86::JS; break;
case X86::JL: ROpcode = X86::JGE; break;
case X86::JGE: ROpcode = X86::JL; break;
case X86::JLE: ROpcode = X86::JG; break;
case X86::JG: ROpcode = X86::JLE; break;
}
MachineBasicBlock* MBB = MI->getParent();
MachineBasicBlock* TMBB = MI->getOperand(0).getMachineBasicBlock();
return BuildMI(*MBB, MBB->erase(MI), ROpcode, 1).addMBB(TMBB);
}