glibc/ports/sysdeps/mips/memcpy.S

631 lines
19 KiB
ArmAsm

/* Copyright (C) 2012-2013 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library. If not, see
<http://www.gnu.org/licenses/>. */
#ifdef ANDROID_CHANGES
#include "machine/asm.h"
#include "machine/regdef.h"
#define USE_MEMMOVE_FOR_OVERLAP
#define PREFETCH_LOAD_HINT PREFETCH_HINT_LOAD_STREAMED
#define PREFETCH_STORE_HINT PREFETCH_HINT_PREPAREFORSTORE
#elif _LIBC
#include <sysdep.h>
#include <regdef.h>
#include <sys/asm.h>
#define PREFETCH_LOAD_HINT PREFETCH_HINT_LOAD_STREAMED
#define PREFETCH_STORE_HINT PREFETCH_HINT_STORE_STREAMED
#elif _COMPILING_NEWLIB
#include "machine/asm.h"
#include "machine/regdef.h"
#define PREFETCH_LOAD_HINT PREFETCH_HINT_LOAD_STREAMED
#define PREFETCH_STORE_HINT PREFETCH_HINT_STORE_STREAMED
#else
#include <regdef.h>
#include <sys/asm.h>
#endif
#if (_MIPS_ISA == _MIPS_ISA_MIPS4) || (_MIPS_ISA == _MIPS_ISA_MIPS5) || \
(_MIPS_ISA == _MIPS_ISA_MIPS32) || (_MIPS_ISA == _MIPS_ISA_MIPS64)
#ifndef DISABLE_PREFETCH
#define USE_PREFETCH
#endif
#endif
#if (_MIPS_SIM == _ABI64) || (_MIPS_SIM == _ABIN32)
#ifndef DISABLE_DOUBLE
#define USE_DOUBLE
#endif
#endif
/* Some asm.h files do not have the L macro definition. */
#ifndef L
#if _MIPS_SIM == _ABIO32
# define L(label) $L ## label
#else
# define L(label) .L ## label
#endif
#endif
/* Some asm.h files do not have the PTR_ADDIU macro definition. */
#ifndef PTR_ADDIU
#ifdef USE_DOUBLE
#define PTR_ADDIU daddiu
#else
#define PTR_ADDIU addiu
#endif
#endif
/* Some asm.h files do not have the PTR_SRA macro definition. */
#ifndef PTR_SRA
#ifdef USE_DOUBLE
#define PTR_SRA dsra
#else
#define PTR_SRA sra
#endif
#endif
/*
* Using PREFETCH_HINT_LOAD_STREAMED instead of PREFETCH_LOAD on load
* prefetches appears to offer a slight preformance advantage.
*
* Using PREFETCH_HINT_PREPAREFORSTORE instead of PREFETCH_STORE
* or PREFETCH_STORE_STREAMED offers a large performance advantage
* but PREPAREFORSTORE has some special restrictions to consider.
*
* Prefetch with the 'prepare for store' hint does not copy a memory
* location into the cache, it just allocates a cache line and zeros
* it out. This means that if you do not write to the entire cache
* line before writing it out to memory some data will get zero'ed out
* when the cache line is written back to memory and data will be lost.
*
* Also if you are using this memcpy to copy overlapping buffers it may
* not behave correctly when using the 'prepare for store' hint. If you
* use the 'prepare for store' prefetch on a memory area that is in the
* memcpy source (as well as the memcpy destination), then you will get
* some data zero'ed out before you have a chance to read it and data will
* be lost.
*
* If you are going to use this memcpy routine with the 'prepare for store'
* prefetch you may want to set USE_MEMMOVE_FOR_OVERLAP in order to avoid
* the problem of running memcpy on overlapping buffers.
*
* There are ifdef'ed sections of this memcpy to make sure that it does not
* do prefetches on cache lines that are not going to be completely written.
* This code is only needed and only used when PREFETCH_STORE_HINT is set to
* PREFETCH_HINT_PREPAREFORSTORE. This code assumes that cache lines are
* 32 bytes and if the cache line is larger it will not work correctly.
*/
#ifdef USE_PREFETCH
# define PREFETCH_HINT_LOAD 0
# define PREFETCH_HINT_STORE 1
# define PREFETCH_HINT_LOAD_STREAMED 4
# define PREFETCH_HINT_STORE_STREAMED 5
# define PREFETCH_HINT_LOAD_RETAINED 6
# define PREFETCH_HINT_STORE_RETAINED 7
# define PREFETCH_HINT_WRITEBACK_INVAL 25
# define PREFETCH_HINT_PREPAREFORSTORE 30
/*
* If we have not picked out what hints to use at this point use the
* standard load and store prefetch hints.
*/
#ifndef PREFETCH_STORE_HINT
# define PREFETCH_STORE_HINT PREFETCH_HINT_STORE
#endif
#ifndef PREFETCH_LOAD_HINT
# define PREFETCH_LOAD_HINT PREFETCH_HINT_LOAD
#endif
/*
* We double everything when USE_DOUBLE is true so we do 2 prefetches to
* get 64 bytes in that case. The assumption is that each individual
* prefetch brings in 32 bytes.
*/
#ifdef USE_DOUBLE
# define PREFETCH_CHUNK 64
# define PREFETCH_FOR_LOAD(chunk, reg) \
pref PREFETCH_LOAD_HINT, (chunk)*32(reg); \
pref PREFETCH_LOAD_HINT, ((chunk)+1)*32(reg)
# define PREFETCH_FOR_STORE(chunk, reg) \
pref PREFETCH_STORE_HINT, (chunk)*32(reg); \
pref PREFETCH_STORE_HINT, ((chunk)+1)*32(reg)
#else
# define PREFETCH_CHUNK 32
# define PREFETCH_FOR_LOAD(chunk, reg) \
pref PREFETCH_LOAD_HINT, (chunk)*32(reg)
# define PREFETCH_FOR_STORE(chunk, reg) \
pref PREFETCH_STORE_HINT, (chunk)*32(reg)
#endif
# define PREFETCH_LIMIT (5 * PREFETCH_CHUNK)
#else /* USE_PREFETCH not defined */
# define PREFETCH_FOR_LOAD(offset, reg)
# define PREFETCH_FOR_STORE(offset, reg)
#endif
/* Allow the routine to be named something else if desired. */
#ifndef MEMCPY_NAME
#define MEMCPY_NAME memcpy
#endif
/* We use these 32/64 bit registers as temporaries to do the copying. */
#define REG0 t0
#define REG1 t1
#define REG2 t2
#define REG3 t3
#if _MIPS_SIM == _ABIO32
# define REG4 t4
# define REG5 t5
# define REG6 t6
# define REG7 t7
#else
# define REG4 ta0
# define REG5 ta1
# define REG6 ta2
# define REG7 ta3
#endif
/* We load/store 64 bits at a time when USE_DOUBLE is true.
* The C_ prefix stands for CHUNK and is used to avoid macro name
* conflicts with system header files. */
#ifdef USE_DOUBLE
# define C_ST sd
# define C_LD ld
#if __MIPSEB
# define C_LDHI ldl /* high part is left in big-endian */
# define C_STHI sdl /* high part is left in big-endian */
# define C_LDLO ldr /* low part is right in big-endian */
# define C_STLO sdr /* low part is right in big-endian */
#else
# define C_LDHI ldr /* high part is right in little-endian */
# define C_STHI sdr /* high part is right in little-endian */
# define C_LDLO ldl /* low part is left in little-endian */
# define C_STLO sdl /* low part is left in little-endian */
#endif
#else
# define C_ST sw
# define C_LD lw
#if __MIPSEB
# define C_LDHI lwl /* high part is left in big-endian */
# define C_STHI swl /* high part is left in big-endian */
# define C_LDLO lwr /* low part is right in big-endian */
# define C_STLO swr /* low part is right in big-endian */
#else
# define C_LDHI lwr /* high part is right in little-endian */
# define C_STHI swr /* high part is right in little-endian */
# define C_LDLO lwl /* low part is left in little-endian */
# define C_STLO swl /* low part is left in little-endian */
#endif
#endif
/* Bookkeeping values for 32 vs. 64 bit mode. */
#ifdef USE_DOUBLE
# define NSIZE 8
# define NSIZEMASK 0x3f
# define NSIZEDMASK 0x7f
#else
# define NSIZE 4
# define NSIZEMASK 0x1f
# define NSIZEDMASK 0x3f
#endif
#define UNIT(unit) ((unit)*NSIZE)
#define UNITM1(unit) (((unit)*NSIZE)-1)
#ifdef ANDROID_CHANGES
LEAF(MEMCPY_NAME, 0)
#else
LEAF(MEMCPY_NAME)
#endif
.set nomips16
.set noreorder
/*
* Below we handle the case where memcpy is called with overlapping src and dst.
* Although memcpy is not required to handle this case, some parts of Android
* like Skia rely on such usage. We call memmove to handle such cases.
*/
#ifdef USE_MEMMOVE_FOR_OVERLAP
PTR_SUBU t0,a0,a1
PTR_SRA t2,t0,31
xor t1,t0,t2
PTR_SUBU t0,t1,t2
sltu t2,t0,a2
beq t2,zero,L(memcpy)
la t9,memmove
jr t9
nop
L(memcpy):
#endif
/*
* If the size is less then 2*NSIZE (8 or 16), go to L(lastb). Regardless of
* size, copy dst pointer to v0 for the return value.
*/
slti t2,a2,(2 * NSIZE)
bne t2,zero,L(lastb)
move v0,a0
/*
* If src and dst have different alignments, go to L(unaligned), if they
* have the same alignment (but are not actually aligned) do a partial
* load/store to make them aligned. If they are both already aligned
* we can start copying at L(aligned).
*/
xor t8,a1,a0
andi t8,t8,(NSIZE-1) /* t8 is a0/a1 word-displacement */
bne t8,zero,L(unaligned)
PTR_SUBU a3, zero, a0
andi a3,a3,(NSIZE-1) /* copy a3 bytes to align a0/a1 */
beq a3,zero,L(aligned) /* if a3=0, it is already aligned */
PTR_SUBU a2,a2,a3 /* a2 is the remining bytes count */
C_LDHI t8,0(a1)
PTR_ADDU a1,a1,a3
C_STHI t8,0(a0)
PTR_ADDU a0,a0,a3
/*
* Now dst/src are both aligned to (word or double word) aligned addresses
* Set a2 to count how many bytes we have to copy after all the 64/128 byte
* chunks are copied and a3 to the dst pointer after all the 64/128 byte
* chunks have been copied. We will loop, incrementing a0 and a1 until a0
* equals a3.
*/
L(aligned):
andi t8,a2,NSIZEDMASK /* any whole 64-byte/128-byte chunks? */
beq a2,t8,L(chkw) /* if a2==t8, no 64-byte/128-byte chunks */
PTR_SUBU a3,a2,t8 /* subtract from a2 the reminder */
PTR_ADDU a3,a0,a3 /* Now a3 is the final dst after loop */
/* When in the loop we may prefetch with the 'prepare to store' hint,
* in this case the a0+x should not be past the "t0-32" address. This
* means: for x=128 the last "safe" a0 address is "t0-160". Alternatively,
* for x=64 the last "safe" a0 address is "t0-96" In the current version we
* will use "prefetch hint,128(a0)", so "t0-160" is the limit.
*/
#if defined(USE_PREFETCH) && (PREFETCH_STORE_HINT == PREFETCH_HINT_PREPAREFORSTORE)
PTR_ADDU t0,a0,a2 /* t0 is the "past the end" address */
PTR_SUBU t9,t0,PREFETCH_LIMIT /* t9 is the "last safe pref" address */
#endif
PREFETCH_FOR_LOAD (0, a1)
PREFETCH_FOR_LOAD (1, a1)
PREFETCH_FOR_LOAD (2, a1)
PREFETCH_FOR_STORE (1, a0)
#if defined(USE_PREFETCH) && (PREFETCH_STORE_HINT == PREFETCH_HINT_PREPAREFORSTORE)
sltu v1,t9,a0 /* If a0 > t9 don't use next prefetch */
bgtz v1,L(loop16w)
nop
#endif
PREFETCH_FOR_STORE (2, a0)
L(loop16w):
PREFETCH_FOR_LOAD (3, a1)
C_LD t0,UNIT(0)(a1)
#if defined(USE_PREFETCH) && (PREFETCH_STORE_HINT == PREFETCH_HINT_PREPAREFORSTORE)
bgtz v1,L(skip_pref30_96)
#endif
C_LD t1,UNIT(1)(a1)
PREFETCH_FOR_STORE (3, a0)
L(skip_pref30_96):
C_LD REG2,UNIT(2)(a1)
C_LD REG3,UNIT(3)(a1)
C_LD REG4,UNIT(4)(a1)
C_LD REG5,UNIT(5)(a1)
C_LD REG6,UNIT(6)(a1)
C_LD REG7,UNIT(7)(a1)
PREFETCH_FOR_LOAD (4, a1)
C_ST t0,UNIT(0)(a0)
C_ST t1,UNIT(1)(a0)
C_ST REG2,UNIT(2)(a0)
C_ST REG3,UNIT(3)(a0)
C_ST REG4,UNIT(4)(a0)
C_ST REG5,UNIT(5)(a0)
C_ST REG6,UNIT(6)(a0)
C_ST REG7,UNIT(7)(a0)
C_LD t0,UNIT(8)(a1)
#if defined(USE_PREFETCH) && (PREFETCH_STORE_HINT == PREFETCH_HINT_PREPAREFORSTORE)
bgtz v1,L(skip_pref30_128)
#endif
C_LD t1,UNIT(9)(a1)
PREFETCH_FOR_STORE (4, a0)
L(skip_pref30_128):
C_LD REG2,UNIT(10)(a1)
C_LD REG3,UNIT(11)(a1)
C_LD REG4,UNIT(12)(a1)
C_LD REG5,UNIT(13)(a1)
C_LD REG6,UNIT(14)(a1)
C_LD REG7,UNIT(15)(a1)
PREFETCH_FOR_LOAD (5, a1)
C_ST t0,UNIT(8)(a0)
C_ST t1,UNIT(9)(a0)
C_ST REG2,UNIT(10)(a0)
C_ST REG3,UNIT(11)(a0)
C_ST REG4,UNIT(12)(a0)
C_ST REG5,UNIT(13)(a0)
C_ST REG6,UNIT(14)(a0)
C_ST REG7,UNIT(15)(a0)
PTR_ADDIU a0,a0,UNIT(16) /* adding 64/128 to dest */
#if defined(USE_PREFETCH) && (PREFETCH_STORE_HINT == PREFETCH_HINT_PREPAREFORSTORE)
sltu v1,t9,a0
#endif
bne a0,a3,L(loop16w)
PTR_ADDIU a1,a1,UNIT(16) /* adding 64/128 to src */
move a2,t8
/* Here we have src and dest word-aligned but less than 64-bytes or
* 128 bytes to go. Check for a 32(64) byte chunk and copy if if there
* is one. Otherwise jump down to L(chk1w) to handle the tail end of
* the copy.
*/
L(chkw):
PREFETCH_FOR_LOAD (0, a1)
andi t8,a2,NSIZEMASK /* Is there a 32-byte/64-byte chunk. */
/* The t8 is the reminder count past 32-bytes */
beq a2,t8,L(chk1w) /* When a2=t8, no 32-byte chunk */
nop
C_LD t0,UNIT(0)(a1)
C_LD t1,UNIT(1)(a1)
C_LD REG2,UNIT(2)(a1)
C_LD REG3,UNIT(3)(a1)
C_LD REG4,UNIT(4)(a1)
C_LD REG5,UNIT(5)(a1)
C_LD REG6,UNIT(6)(a1)
C_LD REG7,UNIT(7)(a1)
PTR_ADDIU a1,a1,UNIT(8)
C_ST t0,UNIT(0)(a0)
C_ST t1,UNIT(1)(a0)
C_ST REG2,UNIT(2)(a0)
C_ST REG3,UNIT(3)(a0)
C_ST REG4,UNIT(4)(a0)
C_ST REG5,UNIT(5)(a0)
C_ST REG6,UNIT(6)(a0)
C_ST REG7,UNIT(7)(a0)
PTR_ADDIU a0,a0,UNIT(8)
/*
* Here we have less then 32(64) bytes to copy. Set up for a loop to
* copy one word (or double word) at a time. Set a2 to count how many
* bytes we have to copy after all the word (or double word) chunks are
* copied and a3 to the dst pointer after all the (d)word chunks have
* been copied. We will loop, incrementing a0 and a1 until a0 equals a3.
*/
L(chk1w):
andi a2,t8,(NSIZE-1) /* a2 is the reminder past one (d)word chunks */
beq a2,t8,L(lastb)
PTR_SUBU a3,t8,a2 /* a3 is count of bytes in one (d)word chunks */
PTR_ADDU a3,a0,a3 /* a3 is the dst address after loop */
/* copying in words (4-byte or 8-byte chunks) */
L(wordCopy_loop):
C_LD REG3,UNIT(0)(a1)
PTR_ADDIU a1,a1,UNIT(1)
PTR_ADDIU a0,a0,UNIT(1)
bne a0,a3,L(wordCopy_loop)
C_ST REG3,UNIT(-1)(a0)
/* Copy the last 8 (or 16) bytes */
L(lastb):
blez a2,L(leave)
PTR_ADDU a3,a0,a2 /* a3 is the last dst address */
L(lastbloop):
lb v1,0(a1)
PTR_ADDIU a1,a1,1
PTR_ADDIU a0,a0,1
bne a0,a3,L(lastbloop)
sb v1,-1(a0)
L(leave):
j ra
nop
/*
* UNALIGNED case, got here with a3 = "negu a0"
* This code is nearly identical to the aligned code above
* but only the destination (not the source) gets aligned
* so we need to do partial loads of the source followed
* by normal stores to the destination (once we have aligned
* the destination).
*/
L(unaligned):
andi a3,a3,(NSIZE-1) /* copy a3 bytes to align a0/a1 */
beqz a3,L(ua_chk16w) /* if a3=0, it is already aligned */
PTR_SUBU a2,a2,a3 /* a2 is the remining bytes count */
C_LDHI v1,UNIT(0)(a1)
C_LDLO v1,UNITM1(1)(a1)
PTR_ADDU a1,a1,a3
C_STHI v1,UNIT(0)(a0)
PTR_ADDU a0,a0,a3
/*
* Now the destination (but not the source) is aligned
* Set a2 to count how many bytes we have to copy after all the 64/128 byte
* chunks are copied and a3 to the dst pointer after all the 64/128 byte
* chunks have been copied. We will loop, incrementing a0 and a1 until a0
* equals a3.
*/
L(ua_chk16w):
andi t8,a2,NSIZEDMASK /* any whole 64-byte/128-byte chunks? */
beq a2,t8,L(ua_chkw) /* if a2==t8, no 64-byte/128-byte chunks */
PTR_SUBU a3,a2,t8 /* subtract from a2 the reminder */
PTR_ADDU a3,a0,a3 /* Now a3 is the final dst after loop */
#if defined(USE_PREFETCH) && (PREFETCH_STORE_HINT == PREFETCH_HINT_PREPAREFORSTORE)
PTR_ADDU t0,a0,a2 /* t0 is the "past the end" address */
PTR_SUBU t9,t0,PREFETCH_LIMIT /* t9 is the "last safe pref" address */
#endif
PREFETCH_FOR_LOAD (0, a1)
PREFETCH_FOR_LOAD (1, a1)
PREFETCH_FOR_LOAD (2, a1)
PREFETCH_FOR_STORE (1, a0)
#if defined(USE_PREFETCH) && (PREFETCH_STORE_HINT == PREFETCH_HINT_PREPAREFORSTORE)
sltu v1,t9,a0
bgtz v1,L(ua_loop16w) /* skip prefetch for too short arrays */
nop
#endif
PREFETCH_FOR_STORE (2, a0)
L(ua_loop16w):
PREFETCH_FOR_LOAD (3, a1)
C_LDHI t0,UNIT(0)(a1)
C_LDLO t0,UNITM1(1)(a1)
C_LDHI t1,UNIT(1)(a1)
#if defined(USE_PREFETCH) && (PREFETCH_STORE_HINT == PREFETCH_HINT_PREPAREFORSTORE)
bgtz v1,L(ua_skip_pref30_96)
#endif
C_LDLO t1,UNITM1(2)(a1)
PREFETCH_FOR_STORE (3, a0)
L(ua_skip_pref30_96):
C_LDHI REG2,UNIT(2)(a1)
C_LDLO REG2,UNITM1(3)(a1)
C_LDHI REG3,UNIT(3)(a1)
C_LDLO REG3,UNITM1(4)(a1)
C_LDHI REG4,UNIT(4)(a1)
C_LDLO REG4,UNITM1(5)(a1)
C_LDHI REG5,UNIT(5)(a1)
C_LDLO REG5,UNITM1(6)(a1)
C_LDHI REG6,UNIT(6)(a1)
C_LDLO REG6,UNITM1(7)(a1)
C_LDHI REG7,UNIT(7)(a1)
C_LDLO REG7,UNITM1(8)(a1)
PREFETCH_FOR_LOAD (4, a1)
C_ST t0,UNIT(0)(a0)
C_ST t1,UNIT(1)(a0)
C_ST REG2,UNIT(2)(a0)
C_ST REG3,UNIT(3)(a0)
C_ST REG4,UNIT(4)(a0)
C_ST REG5,UNIT(5)(a0)
C_ST REG6,UNIT(6)(a0)
C_ST REG7,UNIT(7)(a0)
C_LDHI t0,UNIT(8)(a1)
C_LDLO t0,UNITM1(9)(a1)
C_LDHI t1,UNIT(9)(a1)
#if defined(USE_PREFETCH) && (PREFETCH_STORE_HINT == PREFETCH_HINT_PREPAREFORSTORE)
bgtz v1,L(ua_skip_pref30_128)
#endif
C_LDLO t1,UNITM1(10)(a1)
PREFETCH_FOR_STORE (4, a0)
L(ua_skip_pref30_128):
C_LDHI REG2,UNIT(10)(a1)
C_LDLO REG2,UNITM1(11)(a1)
C_LDHI REG3,UNIT(11)(a1)
C_LDLO REG3,UNITM1(12)(a1)
C_LDHI REG4,UNIT(12)(a1)
C_LDLO REG4,UNITM1(13)(a1)
C_LDHI REG5,UNIT(13)(a1)
C_LDLO REG5,UNITM1(14)(a1)
C_LDHI REG6,UNIT(14)(a1)
C_LDLO REG6,UNITM1(15)(a1)
C_LDHI REG7,UNIT(15)(a1)
C_LDLO REG7,UNITM1(16)(a1)
PREFETCH_FOR_LOAD (5, a1)
C_ST t0,UNIT(8)(a0)
C_ST t1,UNIT(9)(a0)
C_ST REG2,UNIT(10)(a0)
C_ST REG3,UNIT(11)(a0)
C_ST REG4,UNIT(12)(a0)
C_ST REG5,UNIT(13)(a0)
C_ST REG6,UNIT(14)(a0)
C_ST REG7,UNIT(15)(a0)
PTR_ADDIU a0,a0,UNIT(16) /* adding 64/128 to dest */
#if defined(USE_PREFETCH) && (PREFETCH_STORE_HINT == PREFETCH_HINT_PREPAREFORSTORE)
sltu v1,t9,a0
#endif
bne a0,a3,L(ua_loop16w)
PTR_ADDIU a1,a1,UNIT(16) /* adding 64/128 to src */
move a2,t8
/* Here we have src and dest word-aligned but less than 64-bytes or
* 128 bytes to go. Check for a 32(64) byte chunk and copy if if there
* is one. Otherwise jump down to L(ua_chk1w) to handle the tail end of
* the copy. */
L(ua_chkw):
PREFETCH_FOR_LOAD (0, a1)
andi t8,a2,NSIZEMASK /* Is there a 32-byte/64-byte chunk. */
/* t8 is the reminder count past 32-bytes */
beq a2,t8,L(ua_chk1w) /* When a2=t8, no 32-byte chunk */
nop
C_LDHI t0,UNIT(0)(a1)
C_LDLO t0,UNITM1(1)(a1)
C_LDHI t1,UNIT(1)(a1)
C_LDLO t1,UNITM1(2)(a1)
C_LDHI REG2,UNIT(2)(a1)
C_LDLO REG2,UNITM1(3)(a1)
C_LDHI REG3,UNIT(3)(a1)
C_LDLO REG3,UNITM1(4)(a1)
C_LDHI REG4,UNIT(4)(a1)
C_LDLO REG4,UNITM1(5)(a1)
C_LDHI REG5,UNIT(5)(a1)
C_LDLO REG5,UNITM1(6)(a1)
C_LDHI REG6,UNIT(6)(a1)
C_LDLO REG6,UNITM1(7)(a1)
C_LDHI REG7,UNIT(7)(a1)
C_LDLO REG7,UNITM1(8)(a1)
PTR_ADDIU a1,a1,UNIT(8)
C_ST t0,UNIT(0)(a0)
C_ST t1,UNIT(1)(a0)
C_ST REG2,UNIT(2)(a0)
C_ST REG3,UNIT(3)(a0)
C_ST REG4,UNIT(4)(a0)
C_ST REG5,UNIT(5)(a0)
C_ST REG6,UNIT(6)(a0)
C_ST REG7,UNIT(7)(a0)
PTR_ADDIU a0,a0,UNIT(8)
/*
* Here we have less then 32(64) bytes to copy. Set up for a loop to
* copy one word (or double word) at a time.
*/
L(ua_chk1w):
andi a2,t8,(NSIZE-1) /* a2 is the reminder past one (d)word chunks */
beq a2,t8,L(ua_smallCopy)
PTR_SUBU a3,t8,a2 /* a3 is count of bytes in one (d)word chunks */
PTR_ADDU a3,a0,a3 /* a3 is the dst address after loop */
/* copying in words (4-byte or 8-byte chunks) */
L(ua_wordCopy_loop):
C_LDHI v1,UNIT(0)(a1)
C_LDLO v1,UNITM1(1)(a1)
PTR_ADDIU a1,a1,UNIT(1)
PTR_ADDIU a0,a0,UNIT(1)
bne a0,a3,L(ua_wordCopy_loop)
C_ST v1,UNIT(-1)(a0)
/* Copy the last 8 (or 16) bytes */
L(ua_smallCopy):
beqz a2,L(leave)
PTR_ADDU a3,a0,a2 /* a3 is the last dst address */
L(ua_smallCopy_loop):
lb v1,0(a1)
PTR_ADDIU a1,a1,1
PTR_ADDIU a0,a0,1
bne a0,a3,L(ua_smallCopy_loop)
sb v1,-1(a0)
j ra
nop
.set at
.set reorder
END(MEMCPY_NAME)
#ifdef _LIBC
libc_hidden_builtin_def (MEMCPY_NAME)
#endif