📄 memcpy.s
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/************************************************************************ * * memcpy.S * * Memory copy * * ###################################################################### * * mips_start_of_legal_notice * * Copyright (c) 2004 MIPS Technologies, Inc. All rights reserved. * * * Unpublished rights (if any) reserved under the copyright laws of the * United States of America and other countries. * * This code is proprietary to MIPS Technologies, Inc. ("MIPS * Technologies"). Any copying, reproducing, modifying or use of this code * (in whole or in part) that is not expressly permitted in writing by MIPS * Technologies or an authorized third party is strictly prohibited. At a * minimum, this code is protected under unfair competition and copyright * laws. Violations thereof may result in criminal penalties and fines. * * MIPS Technologies reserves the right to change this code to improve * function, design or otherwise. MIPS Technologies does not assume any * liability arising out of the application or use of this code, or of any * error or omission in such code. Any warranties, whether express, * statutory, implied or otherwise, including but not limited to the implied * warranties of merchantability or fitness for a particular purpose, are * excluded. Except as expressly provided in any written license agreement * from MIPS Technologies or an authorized third party, the furnishing of * this code does not give recipient any license to any intellectual * property rights, including any patent rights, that cover this code. * * This code shall not be exported, reexported, transferred, or released, * directly or indirectly, in violation of the law of any country or * international law, regulation, treaty, Executive Order, statute, * amendments or supplements thereto. Should a conflict arise regarding the * export, reexport, transfer, or release of this code, the laws of the * United States of America shall be the governing law. * * This code constitutes one or more of the following: commercial computer * software, commercial computer software documentation or other commercial * items. If the user of this code, or any related documentation of any * kind, including related technical data or manuals, is an agency, * department, or other entity of the United States government * ("Government"), the use, duplication, reproduction, release, * modification, disclosure, or transfer of this code, or any related * documentation of any kind, is restricted in accordance with Federal * Acquisition Regulation 12.212 for civilian agencies and Defense Federal * Acquisition Regulation Supplement 227.7202 for military agencies. The use * of this code by the Government is further restricted in accordance with * the terms of the license agreement(s) and/or applicable contract terms * and conditions covering this code from MIPS Technologies or an authorized * third party. * * * * * mips_end_of_legal_notice * * ************************************************************************//************************************************************************ * Include files ************************************************************************/#include <sysdefs.h>#include <mips.h>/************************************************************************ * Definitions ************************************************************************//************************************************************************ * Public variables ************************************************************************//************************************************************************ * Static variables ************************************************************************//************************************************************************ * Implementation : Public functions ************************************************************************//* This routine could be optimized for MIPS64. The current code only * uses MIPS32 instructions. */ #ifdef EB# define LWHI lwl /* high part is left in big-endian */# define SWHI swl /* high part is left in big-endian */# define LWLO lwr /* low part is right in big-endian */# define SWLO swr /* low part is right in big-endian */#else# define LWHI lwr /* high part is right in little-endian */# define SWHI swr /* high part is right in little-endian */# define LWLO lwl /* low part is left in big-endian */# define SWLO swl /* low part is left in big-endian */#endifLEAF( memcpy ) .set noreorder .set noat slti AT,a2,8 bne AT,zero,last8 move v0,a0 xor t2,a1,a0 andi t2,t2,0x3 # a0/a1 displacement bne t2,zero,shift subu v1,zero,a1 andi v1,v1,0x3 beq v1,zero,chk8w subu a2,a2,v1 LWHI t2,0(a1) addu a1,a1,v1 SWHI t2,0(a0) addu a0,a0,v1chk8w: andi t2,a2,0x1f beq a2,t2,chk1w subu a3,a2,t2 addu a3,a3,a1loop8w: lw t7,0(a1) lw v1,4(a1) lw t0,8(a1) lw t1,12(a1) lw t3,16(a1) lw t4,20(a1) lw t5,24(a1) lw t6,28(a1) sw t7,0(a0) sw v1,4(a0) sw t0,8(a0) sw t1,12(a0) sw t3,16(a0) addiu a1,a1,32 sw t4,20(a0) sw t5,24(a0) addiu a0,a0,32 bne a1,a3,loop8w sw t6,-4(a0) move a2,t2chk1w: andi t2,a2,0x3 beq a2,t2,last8 subu a3,a2,t2 addu a3,a3,a1loop1w: lw t3,0(a1) addiu a1,a1,4 addiu a0,a0,4 bne a1,a3,loop1w sw t3,-4(a0) move a2,t2last8: blez a2,last8e addu a3,a2,a1last8l: lb t2,0(a1) addiu a1,a1,1 addiu a0,a0,1 bne a1,a3,last8l sb t2,-1(a0)last8e: j ra nopshift: subu a3,zero,a0 andi a3,a3,0x3 beq a3,zero,shift1 subu a2,a2,a3 # bytes left LWHI t2,0(a1) LWLO t2,3(a1) addu a1,a1,a3 SWHI t2,0(a0) addu a0,a0,a3shift1: andi t2,a2,0x3 subu a3,a2,t2 addu a3,a3,a1shifth: LWHI t3,0(a1) LWLO t3,3(a1) addiu a1,a1,4 addiu a0,a0,4 bne a1,a3,shifth sw t3,-4(a0) b last8 move a2,t2 .set at .set reorderEND( memcpy )/************************************************************************ * Implementation : Static functions ************************************************************************/
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