Torvald Riegel's semaphore reimplemenation to fix upstream swbz#12674.

commit 042e1521c794a945edc43b5bfa7e69ad70420524

Author: Carlos O'Donell <carlos@systemhalted.org>

Date:   Wed Jan 21 00:46:16 2015 -0500

    Fix semaphore destruction (bug 12674).

    This commit fixes semaphore destruction by either using 64b atomic

    operations (where available), or by using two separate fields when only

    32b atomic operations are available.  In the latter case, we keep a

    conservative estimate of whether there are any waiting threads in one

    bit of the field that counts the number of available tokens, thus

    allowing sem_post to atomically both add a token and determine whether

    it needs to call futex_wake.

    See:

    https://sourceware.org/ml/libc-alpha/2014-12/msg00155.html 

Notes:

* For x86_64 and i686, rather than movign to the generic lll_futex_wake

  we fix the existing versions to return the syscall result and to be

  usable as an R-value.

* We also backport fixes for swbz#18434, and swbz#18138.

* We ignore swbz#17870 because it applies only to x32.

Index: glibc-2.17-c758a686/nptl/DESIGN-sem.txt

===================================================================

--- glibc-2.17-c758a686.orig/nptl/DESIGN-sem.txt

+++ /dev/null

@@ -1,46 +0,0 @@

-Semaphores pseudocode

-==============================

-

-       int sem_wait(sem_t * sem);

-       int sem_trywait(sem_t * sem);

-       int sem_post(sem_t * sem);

-       int sem_getvalue(sem_t * sem, int * sval);

-

-struct sem_t {

-

-   unsigned int count;

-         - current semaphore count, also used as a futex

-}

-

-sem_wait(sem_t *sem)

-{

-  for (;;) {

-

-    if (atomic_decrement_if_positive(sem->count))

-      break;

-

-    futex_wait(&sem->count, 0)

-  }

-}

-

-sem_post(sem_t *sem)

-{

-  n = atomic_increment(sem->count);

-  // Pass the new value of sem->count

-  futex_wake(&sem->count, n + 1);

-}

-

-sem_trywait(sem_t *sem)

-{

-  if (atomic_decrement_if_positive(sem->count)) {

-    return 0;

-  } else {

-    return EAGAIN;

-  }

-}

-

-sem_getvalue(sem_t *sem, int *sval)

-{

-  *sval = sem->count;

-  read_barrier();

-}

Index: glibc-2.17-c758a686/nptl/Makefile

===================================================================

--- glibc-2.17-c758a686.orig/nptl/Makefile

+++ glibc-2.17-c758a686/nptl/Makefile

@@ -95,7 +95,7 @@ libpthread-routines = nptl-init vars eve

 		      sem_init sem_destroy \

 		      sem_open sem_close sem_unlink \

 		      sem_getvalue \

-		      sem_wait sem_trywait sem_timedwait sem_post \

+		      sem_wait sem_timedwait sem_post \

 		      cleanup cleanup_defer cleanup_compat \

 		      cleanup_defer_compat unwind \

 		      pt-longjmp pt-cleanup\

Index: glibc-2.17-c758a686/nptl/sem_getvalue.c

===================================================================

--- glibc-2.17-c758a686.orig/nptl/sem_getvalue.c

+++ glibc-2.17-c758a686/nptl/sem_getvalue.c

@@ -19,23 +19,37 @@

 #include <semaphore.h>

 #include <shlib-compat.h>

 #include "semaphoreP.h"

+#include <atomic.h>

 int

-__new_sem_getvalue (sem, sval)

-     sem_t *sem;

-     int *sval;

+__new_sem_getvalue (sem_t *sem, int *sval)

 {

   struct new_sem *isem = (struct new_sem *) sem;

   /* XXX Check for valid SEM parameter.  */

+  /* FIXME This uses relaxed MO, even though POSIX specifies that this function

+     should be linearizable.  However, its debatable whether linearizability

+     is the right requirement.  We need to follow up with POSIX and, if

+     necessary, use a stronger MO here and elsewhere (e.g., potentially

+     release MO in all places where we consume a token).  */

-  *sval = isem->value;

+#if __HAVE_64B_ATOMICS

+  *sval = atomic_load_relaxed (&isem->data) & SEM_VALUE_MASK;

+#else

+  *sval = atomic_load_relaxed (&isem->value) >> SEM_VALUE_SHIFT;

+#endif

   return 0;

 }

 versioned_symbol (libpthread, __new_sem_getvalue, sem_getvalue, GLIBC_2_1);

 #if SHLIB_COMPAT(libpthread, GLIBC_2_0, GLIBC_2_1)

-strong_alias (__new_sem_getvalue, __old_sem_getvalue)

+int

+__old_sem_getvalue (sem_t *sem, int *sval)

+{

+  struct old_sem *isem = (struct old_sem *) sem;

+  *sval = isem->value;

+  return 0;

+}

 compat_symbol (libpthread, __old_sem_getvalue, sem_getvalue, GLIBC_2_0);

 #endif

Index: glibc-2.17-c758a686/nptl/sem_init.c

===================================================================

--- glibc-2.17-c758a686.orig/nptl/sem_init.c

+++ glibc-2.17-c758a686/nptl/sem_init.c

@@ -18,17 +18,28 @@

 #include <errno.h>

 #include <semaphore.h>

-#include <lowlevellock.h>

 #include <shlib-compat.h>

 #include "semaphoreP.h"

 #include <kernel-features.h>

+/* Returns FUTEX_PRIVATE if pshared is zero and private futexes are supported;

+   returns FUTEX_SHARED otherwise.

+   TODO Remove when cleaning up the futex API throughout glibc.  */

+static __always_inline int

+futex_private_if_supported (int pshared)

+{

+  if (pshared != 0)

+    return LLL_SHARED;

+#ifdef __ASSUME_PRIVATE_FUTEX

+  return LLL_PRIVATE;

+#else

+  return THREAD_GETMEM (THREAD_SELF, header.private_futex)

+      ^ FUTEX_PRIVATE_FLAG;

+#endif

+}

 int

-__new_sem_init (sem, pshared, value)

-     sem_t *sem;

-     int pshared;

-     unsigned int value;

+__new_sem_init (sem_t *sem, int pshared, unsigned int value)

 {

   /* Parameter sanity check.  */

   if (__builtin_expect (value > SEM_VALUE_MAX, 0))

@@ -40,16 +51,15 @@ __new_sem_init (sem, pshared, value)

   /* Map to the internal type.  */

   struct new_sem *isem = (struct new_sem *) sem;

-  /* Use the values the user provided.  */

-  isem->value = value;

-#ifdef __ASSUME_PRIVATE_FUTEX

-  isem->private = pshared ? 0 : FUTEX_PRIVATE_FLAG;

+  /* Use the values the caller provided.  */

+#if __HAVE_64B_ATOMICS

+  isem->data = value;

 #else

-  isem->private = pshared ? 0 : THREAD_GETMEM (THREAD_SELF,

-					       header.private_futex);

+  isem->value = value << SEM_VALUE_SHIFT;

+  isem->nwaiters = 0;

 #endif

-  isem->nwaiters = 0;

+  isem->private = futex_private_if_supported (pshared);

   return 0;

 }

Index: glibc-2.17-c758a686/nptl/sem_open.c

===================================================================

--- glibc-2.17-c758a686.orig/nptl/sem_open.c

+++ glibc-2.17-c758a686/nptl/sem_open.c

@@ -307,9 +307,14 @@ sem_open (const char *name, int oflag, .

 	struct new_sem newsem;

       } sem;

-      sem.newsem.value = value;

-      sem.newsem.private = 0;

+#if __HAVE_64B_ATOMICS

+      sem.newsem.data = value;

+#else

+      sem.newsem.value = value << SEM_VALUE_SHIFT;

       sem.newsem.nwaiters = 0;

+#endif

+      /* This always is a shared semaphore.  */

+      sem.newsem.private = LLL_SHARED;

       /* Initialize the remaining bytes as well.  */

       memset ((char *) &sem.initsem + sizeof (struct new_sem), '\0',

Index: glibc-2.17-c758a686/nptl/tst-sem11.c

===================================================================

--- glibc-2.17-c758a686.orig/nptl/tst-sem11.c

+++ glibc-2.17-c758a686/nptl/tst-sem11.c

@@ -34,8 +34,11 @@ main (void)

       puts ("sem_init failed");

       return 1;

     }

-

+#if __HAVE_64B_ATOMICS

+  if ((u.ns.data >> SEM_NWAITERS_SHIFT) != 0)

+#else

   if (u.ns.nwaiters != 0)

+#endif

     {

       puts ("nwaiters not initialized");

       return 1;

@@ -68,7 +71,11 @@ main (void)

       goto again;

     }

+#if __HAVE_64B_ATOMICS

+  if ((u.ns.data >> SEM_NWAITERS_SHIFT) != 0)

+#else

   if (u.ns.nwaiters != 0)

+#endif

     {

       puts ("nwaiters not reset");

       return 1;

Index: glibc-2.17-c758a686/nptl/tst-sem13.c

===================================================================

--- glibc-2.17-c758a686.orig/nptl/tst-sem13.c

+++ glibc-2.17-c758a686/nptl/tst-sem13.c

@@ -33,9 +33,14 @@ do_test (void)

       perror ("sem_timedwait did not fail with EINVAL");

       return 1;

     }

-  if (u.ns.nwaiters != 0)

+#if __HAVE_64B_ATOMICS

+  unsigned int nwaiters = (u.ns.data >> SEM_NWAITERS_SHIFT);

+#else

+  unsigned int nwaiters = u.ns.nwaiters;

+#endif

+  if (nwaiters != 0)

     {

-      printf ("sem_timedwait modified nwaiters: %ld\n", u.ns.nwaiters);

+      printf ("sem_timedwait modified nwaiters: %d\n", nwaiters);

       return 1;

     }

@@ -52,9 +57,14 @@ do_test (void)

       perror ("2nd sem_timedwait did not fail with ETIMEDOUT");

       return 1;

     }

-  if (u.ns.nwaiters != 0)

+#if __HAVE_64B_ATOMICS

+  nwaiters = (u.ns.data >> SEM_NWAITERS_SHIFT);

+#else

+  nwaiters = u.ns.nwaiters;

+#endif

+  if (nwaiters != 0)

     {

-      printf ("2nd sem_timedwait modified nwaiters: %ld\n", u.ns.nwaiters);

+      printf ("2nd sem_timedwait modified nwaiters: %d\n", nwaiters);

       return 1;

     }

Index: glibc-2.17-c758a686/nptl/sysdeps/unix/sysv/linux/i386/i486/sem_post.S

===================================================================

--- glibc-2.17-c758a686.orig/nptl/sysdeps/unix/sysv/linux/i386/i486/sem_post.S

+++ /dev/null

@@ -1,151 +0,0 @@

-/* Copyright (C) 2002,2003,2005,2007,2008,2011-2012

-   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, see

-   <http://www.gnu.org/licenses/>.  */

-

-#include <sysdep.h>

-#include <shlib-compat.h>

-#include <pthread-errnos.h>

-#include <structsem.h>

-#include <lowlevellock.h>

-

-

-	.text

-

-	.globl	__new_sem_post

-	.type	__new_sem_post,@function

-	.align	16

-__new_sem_post:

-	cfi_startproc

-	pushl	%ebx

-	cfi_adjust_cfa_offset(4)

-	cfi_offset(%ebx, -8)

-

-	movl	8(%esp), %ebx

-

-#if VALUE == 0

-	movl	(%ebx), %eax

-#else

-	movl	VALUE(%ebx), %eax

-#endif

-0:	cmpl	$SEM_VALUE_MAX, %eax

-	je	3f

-	leal	1(%eax), %edx

-	LOCK

-#if VALUE == 0

-	cmpxchgl %edx, (%ebx)

-#else

-	cmpxchgl %edx, VALUE(%ebx)

-#endif

-	jnz	0b

-

-	cmpl	$0, NWAITERS(%ebx)

-	je	2f

-

-	movl	$FUTEX_WAKE, %ecx

-	orl	PRIVATE(%ebx), %ecx

-	movl	$1, %edx

-	movl	$SYS_futex, %eax

-	ENTER_KERNEL

-

-	testl	%eax, %eax

-	js	1f

-

-2:	xorl	%eax, %eax

-	popl	%ebx

-	cfi_adjust_cfa_offset(-4)

-	cfi_restore(%ebx)

-	ret

-

-	cfi_adjust_cfa_offset(4)

-	cfi_offset(%ebx, -8)

-1:

-#ifdef PIC

-	SETUP_PIC_REG(bx)

-#else

-	movl	$4f, %ebx

-4:

-#endif

-	addl	$_GLOBAL_OFFSET_TABLE_, %ebx

-#ifdef NO_TLS_DIRECT_SEG_REFS

-	movl	errno@gotntpoff(%ebx), %edx

-	addl	%gs:0, %edx

-	movl	$EINVAL, (%edx)

-#else

-	movl	errno@gotntpoff(%ebx), %edx

-	movl	$EINVAL, %gs:(%edx)

-#endif

-

-	orl	$-1, %eax

-	popl	%ebx

-	ret

-

-3:

-#ifdef PIC

-	SETUP_PIC_REG(bx)

-#else

-	movl	$5f, %ebx

-5:

-#endif

-	addl	$_GLOBAL_OFFSET_TABLE_, %ebx

-#ifdef NO_TLS_DIRECT_SEG_REFS

-	movl	errno@gotntpoff(%ebx), %edx

-	addl	%gs:0, %edx

-	movl	$EOVERFLOW, (%edx)

-#else

-	movl	errno@gotntpoff(%ebx), %edx

-	movl	$EOVERFLOW, %gs:(%edx)

-#endif

-

-	orl	$-1, %eax

-	popl	%ebx

-	cfi_adjust_cfa_offset(-4)

-	cfi_restore(%ebx)

-	ret

-	cfi_endproc

-	.size	__new_sem_post,.-__new_sem_post

-	versioned_symbol(libpthread, __new_sem_post, sem_post, GLIBC_2_1)

-#if SHLIB_COMPAT(libpthread, GLIBC_2_0, GLIBC_2_1)

-	.global	__old_sem_post

-	.type	__old_sem_post,@function

-__old_sem_post:

-	cfi_startproc

-	pushl	%ebx

-	cfi_adjust_cfa_offset(4)

-	cfi_offset(%ebx, -8)

-

-	movl	8(%esp), %ebx

-	LOCK

-	addl	$1, (%ebx)

-

-	movl	$SYS_futex, %eax

-	movl	$FUTEX_WAKE, %ecx

-	movl	$1, %edx

-	ENTER_KERNEL

-

-	testl	%eax, %eax

-	js	1b

-

-	xorl	%eax, %eax

-	popl	%ebx

-	cfi_adjust_cfa_offset(-4)

-	cfi_restore(%ebx)

-	ret

-	cfi_endproc

-	.size	__old_sem_post,.-__old_sem_post

-	compat_symbol(libpthread, __old_sem_post, sem_post, GLIBC_2_0)

-#endif

Index: glibc-2.17-c758a686/nptl/sysdeps/unix/sysv/linux/i386/i486/sem_timedwait.S

===================================================================

--- glibc-2.17-c758a686.orig/nptl/sysdeps/unix/sysv/linux/i386/i486/sem_timedwait.S

+++ /dev/null

@@ -1,327 +0,0 @@

-/* Copyright (C) 2002-2012 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, see

-   <http://www.gnu.org/licenses/>.  */

-

-#include <sysdep.h>

-#include <shlib-compat.h>

-#include <pthread-errnos.h>

-#include <structsem.h>

-#include <lowlevellock.h>

-

-

-#if VALUE != 0

-# error "code needs to be rewritten for VALUE != 0"

-#endif

-

-

-	.text

-

-	.globl	sem_timedwait

-	.type	sem_timedwait,@function

-	.align	16

-sem_timedwait:

-.LSTARTCODE:

-	movl	4(%esp), %ecx

-

-	movl	(%ecx), %eax

-2:	testl	%eax, %eax

-	je	1f

-

-	leal	-1(%eax), %edx

-	LOCK

-	cmpxchgl %edx, (%ecx)

-	jne	2b

-

-	xorl	%eax, %eax

-	ret

-

-	/* Check whether the timeout value is valid.  */

-1:	pushl	%esi

-.Lpush_esi:

-	pushl	%edi

-.Lpush_edi:

-	pushl	%ebx

-.Lpush_ebx:

-	subl	$12, %esp

-.Lsub_esp:

-

-	movl	32(%esp), %edi

-

-	/* Check for invalid nanosecond field.  */

-	cmpl	$1000000000, 4(%edi)

-	movl	$EINVAL, %esi

-	jae	.Lerrno_exit

-

-	LOCK

-	incl	NWAITERS(%ecx)

-

-7:	xorl	%ecx, %ecx

-	movl	%esp, %ebx

-	movl	%ecx, %edx

-	movl	$__NR_gettimeofday, %eax

-	ENTER_KERNEL

-

-	/* Compute relative timeout.  */

-	movl	4(%esp), %eax

-	movl	$1000, %edx

-	mul	%edx		/* Milli seconds to nano seconds.  */

-	movl	(%edi), %ecx

-	movl	4(%edi), %edx

-	subl	(%esp), %ecx

-	subl	%eax, %edx

-	jns	5f

-	addl	$1000000000, %edx

-	subl	$1, %ecx

-5:	testl	%ecx, %ecx

-	movl	$ETIMEDOUT, %esi

-	js	6f		/* Time is already up.  */

-

-	movl	%ecx, (%esp)	/* Store relative timeout.  */

-	movl	%edx, 4(%esp)

-

-.LcleanupSTART:

-	call	__pthread_enable_asynccancel

-	movl	%eax, 8(%esp)

-

-	movl	28(%esp), %ebx	/* Load semaphore address.  */

-#if FUTEX_WAIT == 0

-	movl	PRIVATE(%ebx), %ecx

-#else

-	movl	$FUTEX_WAIT, %ecx

-	orl	PRIVATE(%ebx), %ecx

-#endif

-	movl	%esp, %esi

-	xorl	%edx, %edx

-	movl	$SYS_futex, %eax

-	ENTER_KERNEL

-	movl	%eax, %esi

-

-	movl	8(%esp), %eax

-	call	__pthread_disable_asynccancel

-.LcleanupEND:

-

-	testl	%esi, %esi

-	je	9f

-	cmpl	$-EWOULDBLOCK, %esi

-	jne	3f

-

-9:	movl	(%ebx), %eax

-8:	testl	%eax, %eax

-	je	7b

-

-	leal	-1(%eax), %ecx

-	LOCK

-	cmpxchgl %ecx, (%ebx)

-	jne	8b

-

-	xorl	%eax, %eax

-

-	LOCK

-	decl	NWAITERS(%ebx)

-

-10:	addl	$12, %esp

-.Ladd_esp:

-	popl	%ebx

-.Lpop_ebx:

-	popl	%edi

-.Lpop_edi:

-	popl	%esi

-.Lpop_esi:

-	ret

-

-.Lafter_ret:

-3:	negl	%esi

-6:

-	movl	28(%esp), %ebx	/* Load semaphore address.  */

-	LOCK

-	decl	NWAITERS(%ebx)

-.Lerrno_exit:

-#ifdef PIC

-	SETUP_PIC_REG(bx)

-#else

-	movl	$4f, %ebx

-4:

-#endif

-	addl	$_GLOBAL_OFFSET_TABLE_, %ebx

-#ifdef NO_TLS_DIRECT_SEG_REFS

-	movl	errno@gotntpoff(%ebx), %edx

-	addl	%gs:0, %edx

-	movl	%esi, (%edx)

-#else

-	movl	errno@gotntpoff(%ebx), %edx

-	movl	%esi, %gs:(%edx)

-#endif

-

-	orl	$-1, %eax

-	jmp	10b

-	.size	sem_timedwait,.-sem_timedwait

-

-

-	.type	sem_wait_cleanup,@function

-sem_wait_cleanup:

-	LOCK

-	decl	NWAITERS(%ebx)

-	movl	%eax, (%esp)

-.LcallUR:

-	call	_Unwind_Resume@PLT

-	hlt

-.LENDCODE:

-	.size	sem_wait_cleanup,.-sem_wait_cleanup

-

-

-	.section .gcc_except_table,"a",@progbits

-.LexceptSTART:

-	.byte	0xff				# @LPStart format (omit)

-	.byte	0xff				# @TType format (omit)

-	.byte	0x01				# call-site format

-						# DW_EH_PE_uleb128

-	.uleb128 .Lcstend-.Lcstbegin

-.Lcstbegin:

-	.uleb128 .LcleanupSTART-.LSTARTCODE

-	.uleb128 .LcleanupEND-.LcleanupSTART

-	.uleb128 sem_wait_cleanup-.LSTARTCODE

-	.uleb128  0

-	.uleb128 .LcallUR-.LSTARTCODE

-	.uleb128 .LENDCODE-.LcallUR

-	.uleb128 0

-	.uleb128  0

-.Lcstend:

-

-

-	.section .eh_frame,"a",@progbits

-.LSTARTFRAME:

-	.long	.LENDCIE-.LSTARTCIE		# Length of the CIE.

-.LSTARTCIE:

-	.long	0				# CIE ID.

-	.byte	1				# Version number.

-#ifdef SHARED

-	.string	"zPLR"				# NUL-terminated augmentation

-						# string.

-#else

-	.string	"zPL"				# NUL-terminated augmentation

-						# string.

-#endif

-	.uleb128 1				# Code alignment factor.

-	.sleb128 -4				# Data alignment factor.

-	.byte	8				# Return address register

-						# column.

-#ifdef SHARED

-	.uleb128 7				# Augmentation value length.

-	.byte	0x9b				# Personality: DW_EH_PE_pcrel

-						# + DW_EH_PE_sdata4

-						# + DW_EH_PE_indirect

-	.long	DW.ref.__gcc_personality_v0-.

-	.byte	0x1b				# LSDA Encoding: DW_EH_PE_pcrel

-						# + DW_EH_PE_sdata4.

-	.byte	0x1b				# FDE Encoding: DW_EH_PE_pcrel

-						# + DW_EH_PE_sdata4.

-#else

-	.uleb128 6				# Augmentation value length.

-	.byte	0x0				# Personality: absolute

-	.long	__gcc_personality_v0

-	.byte	0x0				# LSDA Encoding: absolute

-#endif

-	.byte 0x0c				# DW_CFA_def_cfa

-	.uleb128 4

-	.uleb128 4

-	.byte	0x88				# DW_CFA_offset, column 0x10

-	.uleb128 1

-	.align 4

-.LENDCIE:

-

-	.long	.LENDFDE-.LSTARTFDE		# Length of the FDE.

-.LSTARTFDE:

-	.long	.LSTARTFDE-.LSTARTFRAME		# CIE pointer.

-#ifdef SHARED

-	.long	.LSTARTCODE-.			# PC-relative start address

-						# of the code.

-#else

-	.long	.LSTARTCODE			# Start address of the code.

-#endif

-	.long	.LENDCODE-.LSTARTCODE		# Length of the code.

-	.uleb128 4				# Augmentation size

-#ifdef SHARED

-	.long	.LexceptSTART-.

-#else

-	.long	.LexceptSTART

-#endif

-

-	.byte	4				# DW_CFA_advance_loc4

-	.long	.Lpush_esi-.LSTARTCODE

-	.byte	14				# DW_CFA_def_cfa_offset

-	.uleb128 8

-	.byte   0x86				# DW_CFA_offset %esi

-	.uleb128 2

-	.byte	4				# DW_CFA_advance_loc4

-	.long	.Lpush_edi-.Lpush_esi

-	.byte	14				# DW_CFA_def_cfa_offset

-	.uleb128 12