mirror of
https://github.com/c64scene-ar/llvm-6502.git
synced 2024-11-01 00:11:00 +00:00
a1826c2ecd
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@5182 91177308-0d34-0410-b5e6-96231b3b80d8
54 lines
2.2 KiB
C++
54 lines
2.2 KiB
C++
//===-- X86InstrBuilder.h - Functions to aid building x86 insts -*- C++ -*-===//
|
|
//
|
|
// This file exposes functions that may be used with BuildMI from the
|
|
// MachineInstrBuilder.h file to handle X86'isms in a clean way.
|
|
//
|
|
// The BuildMem function may be used with the BuildMI function to add entire
|
|
// memory references in a single, typed, function call. X86 memory references
|
|
// can be very complex expressions (described in the README), so wrapping them
|
|
// up behind an easier to use interface makes sense. Descriptions of the
|
|
// functions are included below.
|
|
//
|
|
// For reference, the order of operands for memory references is:
|
|
// (Operand), Base, Scale, Index, Displacement.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#ifndef X86INSTRBUILDER_H
|
|
#define X86INSTRBUILDER_H
|
|
|
|
#include "llvm/CodeGen/MachineInstrBuilder.h"
|
|
|
|
/// addDirectMem - This function is used to add a direct memory reference to the
|
|
/// current instruction -- that is, a dereference of an address in a register,
|
|
/// with no scale, index or displacement. An example is: DWORD PTR [EAX].
|
|
///
|
|
inline const MachineInstrBuilder &addDirectMem(const MachineInstrBuilder &MIB,
|
|
unsigned Reg) {
|
|
// Because memory references are always represented with four
|
|
// values, this adds: Reg, [1, NoReg, 0] to the instruction.
|
|
return MIB.addReg(Reg).addZImm(1).addMReg(0).addSImm(0);
|
|
}
|
|
|
|
|
|
/// addRegOffset - This function is used to add a memory reference of the form
|
|
/// [Reg + Offset], i.e., one with no scale or index, but with a
|
|
/// displacement. An example is: DWORD PTR [EAX + 4].
|
|
///
|
|
inline const MachineInstrBuilder &addRegOffset(const MachineInstrBuilder &MIB,
|
|
unsigned Reg, int Offset) {
|
|
return MIB.addReg(Reg).addZImm(1).addMReg(0).addSImm(Offset);
|
|
}
|
|
|
|
/// addFrameReference - This function is used to add a reference to the base of
|
|
/// an abstract object on the stack frame of the current function. This
|
|
/// reference has base register <noreg> and a FrameIndex offset until it is
|
|
/// resolved.
|
|
///
|
|
inline const MachineInstrBuilder &
|
|
addFrameReference(const MachineInstrBuilder &MIB, int FI) {
|
|
return MIB.addReg(0).addZImm(1).addMReg(0).addFrameIndex(FI);
|
|
}
|
|
|
|
#endif
|