llvm/lib/Target/Xtensa/XtensaUtils.cpp

//===--- XtensaUtils.cpp ---- Xtensa Utility Functions ----------*- C++ -*-===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file contains miscellaneous utility functions.
//
//===----------------------------------------------------------------------===//

#include "XtensaUtils.h"

namespace llvm {

bool isValidAddrOffset(int Scale, int64_t OffsetVal) {
  bool Valid = false;

  switch (Scale) {
  case 1:
    Valid = (OffsetVal >= 0 && OffsetVal <= 255);
    break;
  case 2:
    Valid = (OffsetVal >= 0 && OffsetVal <= 510) && ((OffsetVal & 0x1) == 0);
    break;
  case 4:
    Valid = (OffsetVal >= 0 && OffsetVal <= 1020) && ((OffsetVal & 0x3) == 0);
    break;
  default:
    break;
  }
  return Valid;
}

bool isValidAddrOffset(MachineInstr &MI, int64_t Offset) {
  int Scale = 0;

  switch (MI.getOpcode()) {
  case Xtensa::L8UI:
  case Xtensa::S8I:
    Scale = 1;
    break;
  case Xtensa::L16SI:
  case Xtensa::L16UI:
  case Xtensa::S16I:
    Scale = 2;
    break;
  case Xtensa::LEA_ADD:
    return (Offset >= -128 && Offset <= 127);
  default:
    // assume that MI is 32-bit load/store operation
    Scale = 4;
    break;
  }
  return isValidAddrOffset(Scale, Offset);
}

} // namespace llvm