windows-nt/Source/XPSP1/NT/base/ntos/rtl/ia64/bswapi64.s
2020-09-26 16:20:57 +08:00

126 lines
2.2 KiB
ArmAsm
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

// TITLE("Byte Swap Functions")
//++
//
// Copyright (c) 1998 Intel Corporation
// Copyright (c) 1997 Microsoft Corporation
//
// Module Name:
//
// byteswap.s
//
// Abstract:
//
// This module implements functions to perform byte swapping operations.
//
// Author:
//
// William Cheung (v-willc) 30-Nov-1998
//
// Environment:
//
// User or Kernel mode.
//
// Revision History:
//
//--
#include "ksia64.h"
SBTTL("RtlUshortByteSwap")
//++
//
// USHORT
// RtlUshortByteSwap(
// IN USHORT Source
// )
//
// Routine Description:
//
// The RtlUshortByteSwap function exchanges bytes 0 and 1 of Source
// and returns the resulting USHORT.
//
// Arguments:
//
// Source (a0[0..15]) - 16-bit value to byteswap.
//
// Return Value:
//
// The 16-bit integer result is returned as the function value
// in v0[0..15].
//
//--
LEAF_ENTRY(RtlUshortByteSwap)
shl t0 = a0, 48
;;
mux1 v0 = t0, @rev
br.ret.sptk brp
LEAF_EXIT(RtlUshortByteSwap)
SBTTL("RtlUlongByteSwap")
//++
//
// ULONG
// RtlUlongByteSwap(
// IN ULONG Source
// )
//
// Routine Description:
//
// The RtlUlongByteSwap function exchanges byte pairs 0:3 and 1:2 of
// Source and returns the the resulting ULONG.
//
// Arguments:
//
// Source (a0[0..31]) - 32-bit value to byteswap.
//
// Return Value:
//
// The 32-bit integer result is returned as the function value
// in v0[0..31].
//
//--
LEAF_ENTRY(RtlUlongByteSwap)
shl t0 = a0, 32
;;
mux1 v0 = t0, @rev
br.ret.sptk brp
LEAF_EXIT(RtlUlongByteSwap)
SBTTL("RtlUlonglongByteSwap")
//++
//
// ULONG
// RtlUlonglongByteSwap(
// IN ULONGLONG Source
// )
//
// /*++
//
// Routine Description:
//
// The RtlUlonglongByteSwap function exchanges byte pairs 0:7, 1:6, 2:5,
// and 3:4 of Source and returns the resulting ULONGLONG.
//
// Arguments:
//
// Source (a0[0..63]) - 64-bit value to byteswap.
//
// Return Value:
//
// Swapped 64-bit value.
//
//--
LEAF_ENTRY(RtlUlonglongByteSwap)
mux1 v0 = a0, @rev
br.ret.sptk brp
LEAF_EXIT(RtlUlonglongByteSwap)