platform_bionic/libc/arch-mips/string/memset.S
Elliott Hughes d4ca231ae2 Unified sysroot: kill arch-specific include dirs.
<machine/asm.h> was internal use only.

<machine/fenv.h> is quite large, but can live in <bits/...>.

<machine/regdef.h> is trivially replaced by saying $x instead of x in
our assembler.

<machine/setjmp.h> is trivially inlined into <setjmp.h>.

<sgidefs.h> is unused.

Bug: N/A
Test: builds
Change-Id: Id05dbab43a2f9537486efb8f27a5ef167b055815
2017-10-12 13:19:51 -07:00

448 lines
14 KiB
ArmAsm

/*
* Copyright (c) 2013
* MIPS Technologies, Inc., California.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the MIPS Technologies, Inc., nor the names of its
* contributors may be used to endorse or promote products derived from
* this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE MIPS TECHNOLOGIES, INC. ``AS IS'' AND
* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
* ARE DISCLAIMED. IN NO EVENT SHALL THE MIPS TECHNOLOGIES, INC. BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
#ifdef __ANDROID__
# include <private/bionic_asm.h>
# define PREFETCH_STORE_HINT PREFETCH_HINT_PREPAREFORSTORE
#elif _LIBC
# include <sysdep.h>
# include <regdef.h>
# include <sys/asm.h>
# define PREFETCH_STORE_HINT PREFETCH_HINT_PREPAREFORSTORE
#elif _COMPILING_NEWLIB
# include "machine/asm.h"
# include "machine/regdef.h"
# define PREFETCH_STORE_HINT PREFETCH_HINT_PREPAREFORSTORE
#else
# include <regdef.h>
# include <sys/asm.h>
#endif
/* Check to see if the MIPS architecture we are compiling for supports
prefetching. */
#if (__mips == 4) || (__mips == 5) || (__mips == 32) || (__mips == 64)
# ifndef DISABLE_PREFETCH
# define USE_PREFETCH
# endif
#endif
#if defined(_MIPS_SIM) && ((_MIPS_SIM == _ABI64) || (_MIPS_SIM == _ABIN32))
# ifndef DISABLE_DOUBLE
# define USE_DOUBLE
# endif
#endif
#ifndef USE_DOUBLE
# ifndef DISABLE_DOUBLE_ALIGN
# define DOUBLE_ALIGN
# 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
# if _MIPS_SIM == _ABIO32
# define PTR_ADDIU addiu
# else
# define PTR_ADDIU daddiu
# endif
#endif
/* New R6 instructions that may not be in asm.h. */
#ifndef PTR_LSA
# if _MIPS_SIM == _ABIO32
# define PTR_LSA lsa
# else
# define PTR_LSA dlsa
# endif
#endif
/* 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.
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
less than MAX_PREFETCH_SIZE bytes and if the cache line is larger it will
not work correctly. */
#ifdef USE_PREFETCH
# define PREFETCH_HINT_STORE 1
# define PREFETCH_HINT_STORE_STREAMED 5
# define PREFETCH_HINT_STORE_RETAINED 7
# 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
/* 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_STORE(chunk, reg) \
pref PREFETCH_STORE_HINT, (chunk)*64(reg); \
pref PREFETCH_STORE_HINT, ((chunk)*64)+32(reg)
# else
# define PREFETCH_CHUNK 32
# define PREFETCH_FOR_STORE(chunk, reg) \
pref PREFETCH_STORE_HINT, (chunk)*32(reg)
# endif
/* MAX_PREFETCH_SIZE is the maximum size of a prefetch, it must not be less
than PREFETCH_CHUNK, the assumed size of each prefetch. If the real size
of a prefetch is greater than MAX_PREFETCH_SIZE and the PREPAREFORSTORE
hint is used, the code will not work correctly. If PREPAREFORSTORE is not
used than MAX_PREFETCH_SIZE does not matter. */
# define MAX_PREFETCH_SIZE 128
/* PREFETCH_LIMIT is set based on the fact that we never use an offset greater
than 5 on a STORE prefetch and that a single prefetch can never be larger
than MAX_PREFETCH_SIZE. We add the extra 32 when USE_DOUBLE is set because
we actually do two prefetches in that case, one 32 bytes after the other. */
# ifdef USE_DOUBLE
# define PREFETCH_LIMIT (5 * PREFETCH_CHUNK) + 32 + MAX_PREFETCH_SIZE
# else
# define PREFETCH_LIMIT (5 * PREFETCH_CHUNK) + MAX_PREFETCH_SIZE
# endif
# if (PREFETCH_STORE_HINT == PREFETCH_HINT_PREPAREFORSTORE) \
&& ((PREFETCH_CHUNK * 4) < MAX_PREFETCH_SIZE)
/* We cannot handle this because the initial prefetches may fetch bytes that
are before the buffer being copied. We start copies with an offset
of 4 so avoid this situation when using PREPAREFORSTORE. */
# error "PREFETCH_CHUNK is too large and/or MAX_PREFETCH_SIZE is too small."
# endif
#else /* USE_PREFETCH not defined */
# define PREFETCH_FOR_STORE(offset, reg)
#endif
#if __mips_isa_rev > 5
# if (PREFETCH_STORE_HINT == PREFETCH_HINT_PREPAREFORSTORE)
# undef PREFETCH_STORE_HINT
# define PREFETCH_STORE_HINT PREFETCH_HINT_STORE_STREAMED
# endif
# define R6_CODE
#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
# if __MIPSEB
# define C_STHI sdl /* high part is left in big-endian */
# else
# define C_STHI sdr /* high part is right in little-endian */
# endif
#else
# define C_ST sw
# if __MIPSEB
# define C_STHI swl /* high part is left in big-endian */
# else
# define C_STHI swr /* high part is right 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__
LEAF(__memset_chk,0)
#else
LEAF(__memset_chk)
#endif
.set noreorder
sltu $t2, $a3, $a2
beq $t2, $zero, memset
nop
.cpsetup $t9, $t8, __memset_chk
LA $t9, __memset_chk_fail
jr $t9
nop
.set reorder
END(__memset_chk)
#ifdef __ANDROID__
LEAF(memset,0)
#else
LEAF(memset)
#endif
.set nomips16
.set noreorder
/* If the size is less than 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 memset value is not zero, we copy it to all the bytes in a 32 or 64
bit word. */
beq $a1,$zero,L(set0) /* If memset value is zero no smear */
PTR_SUBU $a3,$zero,$a0
nop
/* smear byte into 32 or 64 bit word */
#if ((__mips == 64) || (__mips == 32)) && (__mips_isa_rev >= 2)
# ifdef USE_DOUBLE
dins $a1, $a1, 8, 8 /* Replicate fill byte into half-word. */
dins $a1, $a1, 16, 16 /* Replicate fill byte into word. */
dins $a1, $a1, 32, 32 /* Replicate fill byte into dbl word. */
# else
ins $a1, $a1, 8, 8 /* Replicate fill byte into half-word. */
ins $a1, $a1, 16, 16 /* Replicate fill byte into word. */
# endif
#else
# ifdef USE_DOUBLE
and $a1,0xff
dsll $t2,$a1,8
or $a1,$t2
dsll $t2,$a1,16
or $a1,$t2
dsll $t2,$a1,32
or $a1,$t2
# else
and $a1,0xff
sll $t2,$a1,8
or $a1,$t2
sll $t2,$a1,16
or $a1,$t2
# endif
#endif
/* If the destination address is not aligned do a partial store to get it
aligned. If it is already aligned just jump to L(aligned). */
L(set0):
#ifndef R6_CODE
andi $t2,$a3,(NSIZE-1) /* word-unaligned address? */
beq $t2,$zero,L(aligned) /* t2 is the unalignment count */
PTR_SUBU $a2,$a2,$t2
C_STHI $a1,0($a0)
PTR_ADDU $a0,$a0,$t2
#else /* R6_CODE */
andi $t2,$a0,(NSIZE-1)
lapc $t9,L(atable)
PTR_LSA $t9,$t2,$t9,2
jrc $t9
L(atable):
bc L(aligned)
# ifdef USE_DOUBLE
bc L(lb7)
bc L(lb6)
bc L(lb5)
bc L(lb4)
# endif
bc L(lb3)
bc L(lb2)
bc L(lb1)
L(lb7):
sb $a1,6($a0)
L(lb6):
sb $a1,5($a0)
L(lb5):
sb $a1,4($a0)
L(lb4):
sb $a1,3($a0)
L(lb3):
sb $a1,2($a0)
L(lb2):
sb $a1,1($a0)
L(lb1):
sb $a1,0($a0)
li $t9,NSIZE
subu $t2,$t9,$t2
PTR_SUBU $a2,$a2,$t2
PTR_ADDU $a0,$a0,$t2
#endif /* R6_CODE */
L(aligned):
/* If USE_DOUBLE is not set we may still want to align the data on a 16
byte boundry instead of an 8 byte boundry to maximize the opportunity
of proAptiv chips to do memory bonding (combining two sequential 4
byte stores into one 8 byte store). We know there are at least 4 bytes
left to store or we would have jumped to L(lastb) earlier in the code. */
#ifdef DOUBLE_ALIGN
andi $t2,$a3,4
beq $t2,$zero,L(double_aligned)
PTR_SUBU $a2,$a2,$t2
sw $a1,0($a0)
PTR_ADDU $a0,$a0,$t2
L(double_aligned):
#endif
/* Now the destination is aligned to (word or double word) aligned address
Set a2 to count how many bytes we have to copy after all the 64/128 byte
chunks are copied and a3 to the dest pointer after all the 64/128 byte
chunks have been copied. We will loop, incrementing a0 until it equals
a3. */
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
#if defined(USE_PREFETCH) \
&& (PREFETCH_STORE_HINT != PREFETCH_HINT_PREPAREFORSTORE)
PREFETCH_FOR_STORE (1, $a0)
PREFETCH_FOR_STORE (2, $a0)
PREFETCH_FOR_STORE (3, $a0)
#endif
L(loop16w):
#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(skip_pref)
nop
#endif
#ifndef R6_CODE
PREFETCH_FOR_STORE (4, $a0)
PREFETCH_FOR_STORE (5, $a0)
#else
PREFETCH_FOR_STORE (2, $a0)
#endif
L(skip_pref):
C_ST $a1,UNIT(0)($a0)
C_ST $a1,UNIT(1)($a0)
C_ST $a1,UNIT(2)($a0)
C_ST $a1,UNIT(3)($a0)
C_ST $a1,UNIT(4)($a0)
C_ST $a1,UNIT(5)($a0)
C_ST $a1,UNIT(6)($a0)
C_ST $a1,UNIT(7)($a0)
C_ST $a1,UNIT(8)($a0)
C_ST $a1,UNIT(9)($a0)
C_ST $a1,UNIT(10)($a0)
C_ST $a1,UNIT(11)($a0)
C_ST $a1,UNIT(12)($a0)
C_ST $a1,UNIT(13)($a0)
C_ST $a1,UNIT(14)($a0)
C_ST $a1,UNIT(15)($a0)
PTR_ADDIU $a0,$a0,UNIT(16) /* adding 64/128 to dest */
bne $a0,$a3,L(loop16w)
nop
move $a2,$t8
/* Here we have 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):
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_ST $a1,UNIT(0)($a0)
C_ST $a1,UNIT(1)($a0)
C_ST $a1,UNIT(2)($a0)
C_ST $a1,UNIT(3)($a0)
C_ST $a1,UNIT(4)($a0)
C_ST $a1,UNIT(5)($a0)
C_ST $a1,UNIT(6)($a0)
C_ST $a1,UNIT(7)($a0)
PTR_ADDIU $a0,$a0,UNIT(8)
/* Here we have less than 32(64) bytes to set. 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 dest pointer after all the (d)word chunks have
been copied. We will loop, incrementing a0 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):
PTR_ADDIU $a0,$a0,UNIT(1)
bne $a0,$a3,L(wordCopy_loop)
C_ST $a1,UNIT(-1)($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):
PTR_ADDIU $a0,$a0,1
bne $a0,$a3,L(lastbloop)
sb $a1,-1($a0)
L(leave):
j $ra
nop
.set at
.set reorder
END(memset)
#ifndef __ANDROID__
# ifdef _LIBC
libc_hidden_builtin_def (memset)
libc_hidden_builtin_def (__memset_chk)
# endif
#endif