[thirdparty/glibc.git] / nptl / sysdeps / unix / sysv / linux / x86_64 / sem_wait.S

/* Copyright (C) 2002, 2003 Free Software Foundation, Inc.
   This file is part of the GNU C Library.
   Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.

   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, write to the Free
   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
   02111-1307 USA.  */

#include <sysdep.h>
#include <shlib-compat.h>
#include <pthread-errnos.h>

#ifndef UP
# define LOCK lock
#else
# define
#endif

#define SYS_futex		202


	.text

	.globl	sem_wait
	.type	sem_wait,@function
	.align	16
	cfi_startproc
sem_wait:
	/* First check for cancellation.  */
	movl	%fs:CANCELHANDLING, %eax
	andl	$0xfffffff9, %eax
	cmpl	$8, %eax
	je	4f

	pushq	%r12
	cfi_adjust_cfa_offset(8)
	cfi_offset(12, -16)
	pushq	%r13
	cfi_adjust_cfa_offset(8)
	movq	%rdi, %r13
	cfi_offset(13, -24)

3:	movl	(%r13), %eax
2:	testl	%eax, %eax
	je	1f

	leaq	-1(%rax), %rdx
	LOCK
	cmpxchgl %edx, (%r13)
	jne	2b
	xorl	%eax, %eax

	popq	%r13
	cfi_adjust_cfa_offset(-8)
	cfi_restore(13)
	popq	%r12
	cfi_adjust_cfa_offset(-8)
	cfi_restore(12)

	retq

	cfi_adjust_cfa_offset(16)
	cfi_offset(12, -16)
	cfi_offset(13, -24)
1:	call	__pthread_enable_asynccancel
	movl	%eax, %r8d

	xorq	%r10, %r10
	movq	$SYS_futex, %rax
	movq	%r13, %rdi
	movq	%r10, %rsi
	movq	%r10, %rdx
	syscall
	movq	%rax, %r12

	movl	%r8d, %edi
	call	__pthread_disable_asynccancel

	testq	%r12, %r12
	je	3b
	cmpq	$-EWOULDBLOCK, %r12
	je	3b
	negq	%r12
#if USE___THREAD
	movq	errno@gottpoff(%rip), %rdx
	movl	%r12d, %fs:(%rdx)
#else
	callq	__errno_location@plt
	movl	%r12d, (%rax)
#endif
	orl	$-1, %eax

	popq	%r13
	cfi_adjust_cfa_offset(-8)
	cfi_restore(13)
	popq	%r12
	cfi_adjust_cfa_offset(-8)
	cfi_restore(12)

	retq

4:	/* Canceled.  */
	movq	$0xffffffffffffffff, %fs:RESULT
	LOCK
	orl	$0x10, %fs:CANCELHANDLING
	movq	%fs:CLEANUP_JMP_BUF, %rdi
	jmp	HIDDEN_JUMPTARGET (__pthread_unwind)
	cfi_endproc
	.size	sem_wait,.-sem_wait
Commit	Line	Data
a334319f	1	/* Copyright (C) 2002, 2003 Free Software Foundation, Inc.
db5f2fc9 UD	2	This file is part of the GNU C Library.
	3	Contributed by Ulrich Drepper <drepper@redhat.com>, 2002.
	4
	5	The GNU C Library is free software; you can redistribute it and/or
	6	modify it under the terms of the GNU Lesser General Public
	7	License as published by the Free Software Foundation; either
	8	version 2.1 of the License, or (at your option) any later version.
	9
	10	The GNU C Library is distributed in the hope that it will be useful,
	11	but WITHOUT ANY WARRANTY; without even the implied warranty of
	12	MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
	13	Lesser General Public License for more details.
	14
	15	You should have received a copy of the GNU Lesser General Public
	16	License along with the GNU C Library; if not, write to the Free
	17	Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
	18	02111-1307 USA. */
	19
	20	#include <sysdep.h>
	21	#include <shlib-compat.h>
326132db	22	#include <pthread-errnos.h>
db5f2fc9 UD	23
	24	#ifndef UP
	25	# define LOCK lock
	26	#else
	27	# define
	28	#endif
	29
	30	#define SYS_futex 202
	31
db5f2fc9 UD	32
	33	.text
	34
7588880f UD	35	.globl sem_wait
7588880f UD	36	.type sem_wait,@function
db5f2fc9	37	.align 16
7726edc2	38	cfi_startproc
7588880f	39	sem_wait:
7726edc2 UD	40	/* First check for cancellation. */
	41	movl %fs:CANCELHANDLING, %eax
	42	andl $0xfffffff9, %eax
	43	cmpl $8, %eax
	44	je 4f
	45
	46	pushq %r12
	47	cfi_adjust_cfa_offset(8)
	48	cfi_offset(12, -16)
	49	pushq %r13
	50	cfi_adjust_cfa_offset(8)
	51	movq %rdi, %r13
	52	cfi_offset(13, -24)
	53
	54	3: movl (%r13), %eax
db5f2fc9 UD	55	2: testl %eax, %eax
	56	je 1f
	57
5a03acfe	58	leaq -1(%rax), %rdx
db5f2fc9	59	LOCK
7726edc2	60	cmpxchgl %edx, (%r13)
db5f2fc9 UD	61	jne 2b
	62	xorl %eax, %eax
	63
7726edc2 UD	64	popq %r13
	65	cfi_adjust_cfa_offset(-8)
	66	cfi_restore(13)
	67	popq %r12
	68	cfi_adjust_cfa_offset(-8)
	69	cfi_restore(12)
	70
db5f2fc9 UD	71	retq
db5f2fc9 UD	72
7726edc2 UD	73	cfi_adjust_cfa_offset(16)
	74	cfi_offset(12, -16)
	75	cfi_offset(13, -24)
	76	1: call __pthread_enable_asynccancel
	77	movl %eax, %r8d
	78
	79	xorq %r10, %r10
a334319f	80	movq $SYS_futex, %rax
7726edc2	81	movq %r13, %rdi
db5f2fc9 UD	82	movq %r10, %rsi
	83	movq %r10, %rdx
	84	syscall
7726edc2 UD	85	movq %rax, %r12
	86
	87	movl %r8d, %edi
	88	call __pthread_disable_asynccancel
db5f2fc9	89
7726edc2	90	testq %r12, %r12
db5f2fc9	91	je 3b
7726edc2	92	cmpq $-EWOULDBLOCK, %r12
db5f2fc9	93	je 3b
7726edc2	94	negq %r12
db5f2fc9 UD	95	#if USE___THREAD
db5f2fc9 UD	96	movq errno@gottpoff(%rip), %rdx
7726edc2	97	movl %r12d, %fs:(%rdx)
db5f2fc9	98	#else
6c477888	99	callq __errno_location@plt
7726edc2	100	movl %r12d, (%rax)
db5f2fc9 UD	101	#endif
db5f2fc9 UD	102	orl $-1, %eax
7726edc2 UD	103
	104	popq %r13
	105	cfi_adjust_cfa_offset(-8)
	106	cfi_restore(13)
	107	popq %r12
	108	cfi_adjust_cfa_offset(-8)
	109	cfi_restore(12)
	110
db5f2fc9	111	retq
7726edc2 UD	112
	113	4: /* Canceled. */
	114	movq $0xffffffffffffffff, %fs:RESULT
	115	LOCK
	116	orl $0x10, %fs:CANCELHANDLING
	117	movq %fs:CLEANUP_JMP_BUF, %rdi
da0c02ee	118	jmp HIDDEN_JUMPTARGET (__pthread_unwind)
7726edc2	119	cfi_endproc
7588880f	120	.size sem_wait,.-sem_wait