platform_bionic/libc/arch-arm64/bionic/_setjmp.S
Elliott Hughes fff3c0fdcf Align arm64 stacks to 16 bytes in __bionic_clone.
Also ensure that arm64/x86-64/x86 assembler uses local labels.
(There are are so many non-local labels in arm that fixing them
seems out of scope.)

Also synchronize the __bionic_clone.S comments.

Change-Id: I03b4f84780d996b54d6637a074638196bbb01cd4
2014-05-09 12:16:20 -07:00

111 lines
3.9 KiB
ArmAsm

/*
* Copyright (C) 2013 The Android Open Source Project
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* * Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* * 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 COPYRIGHT HOLDERS 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
* COPYRIGHT OWNER 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 <private/bionic_asm.h>
#include <machine/setjmp.h>
/*
* C library - _setjmp, _longjmp
*
* _longjmp(jmp_buf state, int value)
* will generate a "return(v)" from the last call to _setjmp(state) by restoring
* registers from the stack. The previous signal state is NOT restored.
*
* NOTE: x0 return value
* x9-x15 temporary registers
*/
ENTRY(_setjmp)
/* store magic number */
ldr w9, .L_setjmp_magic
str w9, [x0, #(_JB_MAGIC * 4)]
/* store core registers */
mov x10, sp
stp x30, x10, [x0, #(_JB_CORE_BASE * 4 + 16 * 0)]
stp x28, x29, [x0, #(_JB_CORE_BASE * 4 + 16 * 1)]
stp x26, x27, [x0, #(_JB_CORE_BASE * 4 + 16 * 2)]
stp x24, x25, [x0, #(_JB_CORE_BASE * 4 + 16 * 3)]
stp x22, x23, [x0, #(_JB_CORE_BASE * 4 + 16 * 4)]
stp x20, x21, [x0, #(_JB_CORE_BASE * 4 + 16 * 5)]
str x19, [x0, #(_JB_CORE_BASE * 4 + 16 * 6)]
/* store floating point registers */
stp d14, d15, [x0, #(_JB_FLOAT_BASE * 4 + 16 * 0)]
stp d12, d13, [x0, #(_JB_FLOAT_BASE * 4 + 16 * 1)]
stp d10, d11, [x0, #(_JB_FLOAT_BASE * 4 + 16 * 2)]
stp d8, d9, [x0, #(_JB_FLOAT_BASE * 4 + 16 * 3)]
mov w0, wzr
ret
END(_setjmp)
.L_setjmp_magic:
.word _JB_MAGIC__SETJMP
ENTRY(_longjmp)
/* check magic */
ldr w9, .L_setjmp_magic
ldr w10, [x0, #(_JB_MAGIC * 4)]
cmp w9, w10
b.ne .L_fail
/* restore core registers */
ldp x30, x10, [x0, #(_JB_CORE_BASE * 4 + 16 * 0)]
mov sp, x10
ldp x28, x29, [x0, #(_JB_CORE_BASE * 4 + 16 * 1)]
ldp x26, x27, [x0, #(_JB_CORE_BASE * 4 + 16 * 2)]
ldp x24, x25, [x0, #(_JB_CORE_BASE * 4 + 16 * 3)]
ldp x22, x23, [x0, #(_JB_CORE_BASE * 4 + 16 * 4)]
ldp x20, x21, [x0, #(_JB_CORE_BASE * 4 + 16 * 5)]
ldr x19, [x0, #(_JB_CORE_BASE * 4 + 16 * 6)]
/* restore floating point registers */
ldp d14, d15, [x0, #(_JB_FLOAT_BASE * 4 + 16 * 0)]
ldp d12, d13, [x0, #(_JB_FLOAT_BASE * 4 + 16 * 1)]
ldp d10, d11, [x0, #(_JB_FLOAT_BASE * 4 + 16 * 2)]
ldp d8, d9, [x0, #(_JB_FLOAT_BASE * 4 + 16 * 3)]
/* validate sp (sp mod 16 = 0) and lr (lr mod 4 = 0) */
tst x30, #3
b.ne .L_fail
mov x10, sp
tst x10, #15
b.ne .L_fail
/* set return value */
cmp w1, wzr
csinc w0, w1, wzr, ne
ret
/* validation failed, die die die */
.L_fail:
bl PIC_SYM(longjmperror, PLT)
bl PIC_SYM(abort, PLT)
b . - 8 /* Cannot get here */
END(_longjmp)