freebsd-dev/lib/libc/arm/string/memmove.S
Konstantin Belousov 96cdb0ab9d Annotate arm userspace assembler sources stating their tolerance to
the non-executable stack.

Reviewed by:	andrew
Sponsored by:	The FreeBSD Foundation
2015-09-29 16:09:58 +00:00

614 lines
13 KiB
ArmAsm

/* $NetBSD: memmove.S,v 1.4 2003/10/14 07:51:45 scw Exp $ */
/*-
* Copyright (c) 1997 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Neil A. Carson and Mark Brinicombe
*
* 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.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS
* ``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 FOUNDATION OR CONTRIBUTORS
* 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.
*/
#include <machine/asm.h>
__FBSDID("$FreeBSD$");
.syntax unified
#ifndef _BCOPY
/* LINTSTUB: Func: void *memmove(void *, const void *, size_t) */
ENTRY(memmove)
#else
/* bcopy = memcpy/memmove with arguments reversed. */
/* LINTSTUB: Func: void bcopy(void *, void *, size_t) */
ENTRY(bcopy)
/* switch the source and destination registers */
eor r0, r1, r0
eor r1, r0, r1
eor r0, r1, r0
#endif
/* Do the buffers overlap? */
cmp r0, r1
it eq
RETeq /* Bail now if src/dst are the same */
ite cc
subcc r3, r0, r1 /* if (dst > src) r3 = dst - src */
subcs r3, r1, r0 /* if (src > dsr) r3 = src - dst */
cmp r3, r2 /* if (r3 < len) we have an overlap */
bcc PIC_SYM(_C_LABEL(memcpy), PLT)
/* Determine copy direction */
cmp r1, r0
it cc
bcc .Lmemmove_backwards
itt eq
moveq r0, #0 /* Quick abort for len=0 */
RETeq
stmdb sp!, {r0, lr} /* memmove() returns dest addr */
subs r2, r2, #4
blt .Lmemmove_fl4 /* less than 4 bytes */
ands r12, r0, #3
bne .Lmemmove_fdestul /* oh unaligned destination addr */
ands r12, r1, #3
bne .Lmemmove_fsrcul /* oh unaligned source addr */
.Lmemmove_ft8:
/* We have aligned source and destination */
subs r2, r2, #8
blt .Lmemmove_fl12 /* less than 12 bytes (4 from above) */
subs r2, r2, #0x14
blt .Lmemmove_fl32 /* less than 32 bytes (12 from above) */
stmdb sp!, {r4} /* borrow r4 */
/* blat 32 bytes at a time */
/* XXX for really big copies perhaps we should use more registers */
.Lmemmove_floop32:
ldmia r1!, {r3, r4, r12, lr}
stmia r0!, {r3, r4, r12, lr}
ldmia r1!, {r3, r4, r12, lr}
stmia r0!, {r3, r4, r12, lr}
subs r2, r2, #0x20
bge .Lmemmove_floop32
cmn r2, #0x10
ittt ge
ldmiage r1!, {r3, r4, r12, lr} /* blat a remaining 16 bytes */
stmiage r0!, {r3, r4, r12, lr}
subge r2, r2, #0x10
ldmia sp!, {r4} /* return r4 */
.Lmemmove_fl32:
adds r2, r2, #0x14
/* blat 12 bytes at a time */
.Lmemmove_floop12:
ittt ge
ldmiage r1!, {r3, r12, lr}
stmiage r0!, {r3, r12, lr}
subsge r2, r2, #0x0c
bge .Lmemmove_floop12
.Lmemmove_fl12:
adds r2, r2, #8
blt .Lmemmove_fl4
subs r2, r2, #4
itt lt
ldrlt r3, [r1], #4
strlt r3, [r0], #4
ittt ge
ldmiage r1!, {r3, r12}
stmiage r0!, {r3, r12}
subge r2, r2, #4
.Lmemmove_fl4:
/* less than 4 bytes to go */
adds r2, r2, #4
it eq
ldmiaeq sp!, {r0, pc} /* done */
/* copy the crud byte at a time */
cmp r2, #2
ldrb r3, [r1], #1
strb r3, [r0], #1
itt ge
ldrbge r3, [r1], #1
strbge r3, [r0], #1
itt gt
ldrbgt r3, [r1], #1
strbgt r3, [r0], #1
ldmia sp!, {r0, pc}
/* erg - unaligned destination */
.Lmemmove_fdestul:
rsb r12, r12, #4
cmp r12, #2
/* align destination with byte copies */
ldrb r3, [r1], #1
strb r3, [r0], #1
itt ge
ldrbge r3, [r1], #1
strbge r3, [r0], #1
itt gt
ldrbgt r3, [r1], #1
strbgt r3, [r0], #1
subs r2, r2, r12
blt .Lmemmove_fl4 /* less the 4 bytes */
ands r12, r1, #3
beq .Lmemmove_ft8 /* we have an aligned source */
/* erg - unaligned source */
/* This is where it gets nasty ... */
.Lmemmove_fsrcul:
bic r1, r1, #3
ldr lr, [r1], #4
cmp r12, #2
bgt .Lmemmove_fsrcul3
beq .Lmemmove_fsrcul2
cmp r2, #0x0c
blt .Lmemmove_fsrcul1loop4
sub r2, r2, #0x0c
stmdb sp!, {r4, r5}
.Lmemmove_fsrcul1loop16:
#ifdef __ARMEB__
mov r3, lr, lsl #8
#else
mov r3, lr, lsr #8
#endif
ldmia r1!, {r4, r5, r12, lr}
#ifdef __ARMEB__
orr r3, r3, r4, lsr #24
mov r4, r4, lsl #8
orr r4, r4, r5, lsr #24
mov r5, r5, lsl #8
orr r5, r5, r12, lsr #24
mov r12, r12, lsl #8
orr r12, r12, lr, lsr #24
#else
orr r3, r3, r4, lsl #24
mov r4, r4, lsr #8
orr r4, r4, r5, lsl #24
mov r5, r5, lsr #8
orr r5, r5, r12, lsl #24
mov r12, r12, lsr #8
orr r12, r12, lr, lsl #24
#endif
stmia r0!, {r3-r5, r12}
subs r2, r2, #0x10
bge .Lmemmove_fsrcul1loop16
ldmia sp!, {r4, r5}
adds r2, r2, #0x0c
blt .Lmemmove_fsrcul1l4
.Lmemmove_fsrcul1loop4:
#ifdef __ARMEB__
mov r12, lr, lsl #8
#else
mov r12, lr, lsr #8
#endif
ldr lr, [r1], #4
#ifdef __ARMEB__
orr r12, r12, lr, lsr #24
#else
orr r12, r12, lr, lsl #24
#endif
str r12, [r0], #4
subs r2, r2, #4
bge .Lmemmove_fsrcul1loop4
.Lmemmove_fsrcul1l4:
sub r1, r1, #3
b .Lmemmove_fl4
.Lmemmove_fsrcul2:
cmp r2, #0x0c
blt .Lmemmove_fsrcul2loop4
sub r2, r2, #0x0c
stmdb sp!, {r4, r5}
.Lmemmove_fsrcul2loop16:
#ifdef __ARMEB__
mov r3, lr, lsl #16
#else
mov r3, lr, lsr #16
#endif
ldmia r1!, {r4, r5, r12, lr}
#ifdef __ARMEB__
orr r3, r3, r4, lsr #16
mov r4, r4, lsl #16
orr r4, r4, r5, lsr #16
mov r5, r5, lsl #16
orr r5, r5, r12, lsr #16
mov r12, r12, lsl #16
orr r12, r12, lr, lsr #16
#else
orr r3, r3, r4, lsl #16
mov r4, r4, lsr #16
orr r4, r4, r5, lsl #16
mov r5, r5, lsr #16
orr r5, r5, r12, lsl #16
mov r12, r12, lsr #16
orr r12, r12, lr, lsl #16
#endif
stmia r0!, {r3-r5, r12}
subs r2, r2, #0x10
bge .Lmemmove_fsrcul2loop16
ldmia sp!, {r4, r5}
adds r2, r2, #0x0c
blt .Lmemmove_fsrcul2l4
.Lmemmove_fsrcul2loop4:
#ifdef __ARMEB__
mov r12, lr, lsl #16
#else
mov r12, lr, lsr #16
#endif
ldr lr, [r1], #4
#ifdef __ARMEB__
orr r12, r12, lr, lsr #16
#else
orr r12, r12, lr, lsl #16
#endif
str r12, [r0], #4
subs r2, r2, #4
bge .Lmemmove_fsrcul2loop4
.Lmemmove_fsrcul2l4:
sub r1, r1, #2
b .Lmemmove_fl4
.Lmemmove_fsrcul3:
cmp r2, #0x0c
blt .Lmemmove_fsrcul3loop4
sub r2, r2, #0x0c
stmdb sp!, {r4, r5}
.Lmemmove_fsrcul3loop16:
#ifdef __ARMEB__
mov r3, lr, lsl #24
#else
mov r3, lr, lsr #24
#endif
ldmia r1!, {r4, r5, r12, lr}
#ifdef __ARMEB__
orr r3, r3, r4, lsr #8
mov r4, r4, lsl #24
orr r4, r4, r5, lsr #8
mov r5, r5, lsl #24
orr r5, r5, r12, lsr #8
mov r12, r12, lsl #24
orr r12, r12, lr, lsr #8
#else
orr r3, r3, r4, lsl #8
mov r4, r4, lsr #24
orr r4, r4, r5, lsl #8
mov r5, r5, lsr #24
orr r5, r5, r12, lsl #8
mov r12, r12, lsr #24
orr r12, r12, lr, lsl #8
#endif
stmia r0!, {r3-r5, r12}
subs r2, r2, #0x10
bge .Lmemmove_fsrcul3loop16
ldmia sp!, {r4, r5}
adds r2, r2, #0x0c
blt .Lmemmove_fsrcul3l4
.Lmemmove_fsrcul3loop4:
#ifdef __ARMEB__
mov r12, lr, lsl #24
#else
mov r12, lr, lsr #24
#endif
ldr lr, [r1], #4
#ifdef __ARMEB__
orr r12, r12, lr, lsr #8
#else
orr r12, r12, lr, lsl #8
#endif
str r12, [r0], #4
subs r2, r2, #4
bge .Lmemmove_fsrcul3loop4
.Lmemmove_fsrcul3l4:
sub r1, r1, #1
b .Lmemmove_fl4
.Lmemmove_backwards:
add r1, r1, r2
add r0, r0, r2
subs r2, r2, #4
blt .Lmemmove_bl4 /* less than 4 bytes */
ands r12, r0, #3
bne .Lmemmove_bdestul /* oh unaligned destination addr */
ands r12, r1, #3
bne .Lmemmove_bsrcul /* oh unaligned source addr */
.Lmemmove_bt8:
/* We have aligned source and destination */
subs r2, r2, #8
blt .Lmemmove_bl12 /* less than 12 bytes (4 from above) */
stmdb sp!, {r4, lr}
subs r2, r2, #0x14 /* less than 32 bytes (12 from above) */
blt .Lmemmove_bl32
/* blat 32 bytes at a time */
/* XXX for really big copies perhaps we should use more registers */
.Lmemmove_bloop32:
ldmdb r1!, {r3, r4, r12, lr}
stmdb r0!, {r3, r4, r12, lr}
ldmdb r1!, {r3, r4, r12, lr}
stmdb r0!, {r3, r4, r12, lr}
subs r2, r2, #0x20
bge .Lmemmove_bloop32
.Lmemmove_bl32:
cmn r2, #0x10
ittt ge
ldmdbge r1!, {r3, r4, r12, lr} /* blat a remaining 16 bytes */
stmdbge r0!, {r3, r4, r12, lr}
subge r2, r2, #0x10
adds r2, r2, #0x14
ittt ge
ldmdbge r1!, {r3, r12, lr} /* blat a remaining 12 bytes */
stmdbge r0!, {r3, r12, lr}
subge r2, r2, #0x0c
ldmia sp!, {r4, lr}
.Lmemmove_bl12:
adds r2, r2, #8
blt .Lmemmove_bl4
subs r2, r2, #4
itt lt
ldrlt r3, [r1, #-4]!
strlt r3, [r0, #-4]!
ittt ge
ldmdbge r1!, {r3, r12}
stmdbge r0!, {r3, r12}
subge r2, r2, #4
.Lmemmove_bl4:
/* less than 4 bytes to go */
adds r2, r2, #4
it eq
RETeq /* done */
/* copy the crud byte at a time */
cmp r2, #2
ldrb r3, [r1, #-1]!
strb r3, [r0, #-1]!
itt ge
ldrbge r3, [r1, #-1]!
strbge r3, [r0, #-1]!
itt gt
ldrbgt r3, [r1, #-1]!
strbgt r3, [r0, #-1]!
RET
/* erg - unaligned destination */
.Lmemmove_bdestul:
cmp r12, #2
/* align destination with byte copies */
ldrb r3, [r1, #-1]!
strb r3, [r0, #-1]!
itt ge
ldrbge r3, [r1, #-1]!
strbge r3, [r0, #-1]!
itt gt
ldrbgt r3, [r1, #-1]!
strbgt r3, [r0, #-1]!
subs r2, r2, r12
blt .Lmemmove_bl4 /* less than 4 bytes to go */
ands r12, r1, #3
beq .Lmemmove_bt8 /* we have an aligned source */
/* erg - unaligned source */
/* This is where it gets nasty ... */
.Lmemmove_bsrcul:
bic r1, r1, #3
ldr r3, [r1, #0]
cmp r12, #2
blt .Lmemmove_bsrcul1
beq .Lmemmove_bsrcul2
cmp r2, #0x0c
blt .Lmemmove_bsrcul3loop4
sub r2, r2, #0x0c
stmdb sp!, {r4, r5, lr}
.Lmemmove_bsrcul3loop16:
#ifdef __ARMEB__
mov lr, r3, lsr #8
#else
mov lr, r3, lsl #8
#endif
ldmdb r1!, {r3-r5, r12}
#ifdef __ARMEB__
orr lr, lr, r12, lsl #24
mov r12, r12, lsr #8
orr r12, r12, r5, lsl #24
mov r5, r5, lsr #8
orr r5, r5, r4, lsl #24
mov r4, r4, lsr #8
orr r4, r4, r3, lsl #24
#else
orr lr, lr, r12, lsr #24
mov r12, r12, lsl #8
orr r12, r12, r5, lsr #24
mov r5, r5, lsl #8
orr r5, r5, r4, lsr #24
mov r4, r4, lsl #8
orr r4, r4, r3, lsr #24
#endif
stmdb r0!, {r4, r5, r12, lr}
subs r2, r2, #0x10
bge .Lmemmove_bsrcul3loop16
ldmia sp!, {r4, r5, lr}
adds r2, r2, #0x0c
blt .Lmemmove_bsrcul3l4
.Lmemmove_bsrcul3loop4:
#ifdef __ARMEB__
mov r12, r3, lsr #8
#else
mov r12, r3, lsl #8
#endif
ldr r3, [r1, #-4]!
#ifdef __ARMEB__
orr r12, r12, r3, lsl #24
#else
orr r12, r12, r3, lsr #24
#endif
str r12, [r0, #-4]!
subs r2, r2, #4
bge .Lmemmove_bsrcul3loop4
.Lmemmove_bsrcul3l4:
add r1, r1, #3
b .Lmemmove_bl4
.Lmemmove_bsrcul2:
cmp r2, #0x0c
blt .Lmemmove_bsrcul2loop4
sub r2, r2, #0x0c
stmdb sp!, {r4, r5, lr}
.Lmemmove_bsrcul2loop16:
#ifdef __ARMEB__
mov lr, r3, lsr #16
#else
mov lr, r3, lsl #16
#endif
ldmdb r1!, {r3-r5, r12}
#ifdef __ARMEB__
orr lr, lr, r12, lsl #16
mov r12, r12, lsr #16
orr r12, r12, r5, lsl #16
mov r5, r5, lsr #16
orr r5, r5, r4, lsl #16
mov r4, r4, lsr #16
orr r4, r4, r3, lsl #16
#else
orr lr, lr, r12, lsr #16
mov r12, r12, lsl #16
orr r12, r12, r5, lsr #16
mov r5, r5, lsl #16
orr r5, r5, r4, lsr #16
mov r4, r4, lsl #16
orr r4, r4, r3, lsr #16
#endif
stmdb r0!, {r4, r5, r12, lr}
subs r2, r2, #0x10
bge .Lmemmove_bsrcul2loop16
ldmia sp!, {r4, r5, lr}
adds r2, r2, #0x0c
blt .Lmemmove_bsrcul2l4
.Lmemmove_bsrcul2loop4:
#ifdef __ARMEB__
mov r12, r3, lsr #16
#else
mov r12, r3, lsl #16
#endif
ldr r3, [r1, #-4]!
#ifdef __ARMEB__
orr r12, r12, r3, lsl #16
#else
orr r12, r12, r3, lsr #16
#endif
str r12, [r0, #-4]!
subs r2, r2, #4
bge .Lmemmove_bsrcul2loop4
.Lmemmove_bsrcul2l4:
add r1, r1, #2
b .Lmemmove_bl4
.Lmemmove_bsrcul1:
cmp r2, #0x0c
blt .Lmemmove_bsrcul1loop4
sub r2, r2, #0x0c
stmdb sp!, {r4, r5, lr}
.Lmemmove_bsrcul1loop32:
#ifdef __ARMEB__
mov lr, r3, lsr #24
#else
mov lr, r3, lsl #24
#endif
ldmdb r1!, {r3-r5, r12}
#ifdef __ARMEB__
orr lr, lr, r12, lsl #8
mov r12, r12, lsr #24
orr r12, r12, r5, lsl #8
mov r5, r5, lsr #24
orr r5, r5, r4, lsl #8
mov r4, r4, lsr #24
orr r4, r4, r3, lsl #8
#else
orr lr, lr, r12, lsr #8
mov r12, r12, lsl #24
orr r12, r12, r5, lsr #8
mov r5, r5, lsl #24
orr r5, r5, r4, lsr #8
mov r4, r4, lsl #24
orr r4, r4, r3, lsr #8
#endif
stmdb r0!, {r4, r5, r12, lr}
subs r2, r2, #0x10
bge .Lmemmove_bsrcul1loop32
ldmia sp!, {r4, r5, lr}
adds r2, r2, #0x0c
blt .Lmemmove_bsrcul1l4
.Lmemmove_bsrcul1loop4:
#ifdef __ARMEB__
mov r12, r3, lsr #24
#else
mov r12, r3, lsl #24
#endif
ldr r3, [r1, #-4]!
#ifdef __ARMEB__
orr r12, r12, r3, lsl #8
#else
orr r12, r12, r3, lsr #8
#endif
str r12, [r0, #-4]!
subs r2, r2, #4
bge .Lmemmove_bsrcul1loop4
.Lmemmove_bsrcul1l4:
add r1, r1, #1
b .Lmemmove_bl4
#ifndef _BCOPY
END(memmove)
#else
END(bcopy)
#endif
.section .note.GNU-stack,"",%progbits