0,0 → 1,164 |
/* Thread library support for -fsplit-stack. */ |
/* Copyright (C) 2009-2015 Free Software Foundation, Inc. |
Contributed by Ian Lance Taylor <iant@google.com>. |
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This file is part of GCC. |
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GCC is free software; you can redistribute it and/or modify it under |
the terms of the GNU General Public License as published by the Free |
Software Foundation; either version 3, or (at your option) any later |
version. |
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GCC 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 General Public License |
for more details. |
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Under Section 7 of GPL version 3, you are granted additional |
permissions described in the GCC Runtime Library Exception, version |
3.1, as published by the Free Software Foundation. |
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You should have received a copy of the GNU General Public License and |
a copy of the GCC Runtime Library Exception along with this program; |
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see |
<http://www.gnu.org/licenses/>. */ |
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#include "tconfig.h" |
#include "tsystem.h" |
#include "coretypes.h" |
#include "tm.h" |
#include "libgcc_tm.h" |
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/* If inhibit_libc is defined, we can not compile this file. The |
effect is that people will not be able to use -fsplit-stack. That |
is much better than failing the build particularly since people |
will want to define inhibit_libc while building a compiler which |
can build glibc. */ |
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#ifndef inhibit_libc |
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#include <errno.h> |
#include <pthread.h> |
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#include "generic-morestack.h" |
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/* We declare the pthread functions we need as weak, so that |
libgcc_s.so does not need to be linked against -lpthread. */ |
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extern int pthread_once (pthread_once_t *, void (*) (void)) |
__attribute__ ((weak)); |
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extern int pthread_key_create (pthread_key_t *, void (*) (void *)) |
__attribute__ ((weak)); |
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extern int pthread_setspecific (pthread_key_t, const void *) |
__attribute__ ((weak)); |
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/* The key for the list of stack segments to free when the thread |
exits. This is created by pthread_key_create. */ |
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static pthread_key_t segment_list_key; |
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/* Used to only run create_key once. */ |
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static pthread_once_t create_key_once = PTHREAD_ONCE_INIT; |
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/* Release all the segments for a thread. This is the destructor |
function used by pthread_key_create, and is called when a thread |
exits. */ |
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static void |
free_segments (void* arg) |
{ |
__morestack_release_segments ((struct stack_segment **) arg, 1); |
} |
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/* Set up the key for the list of segments. This is called via |
pthread_once. */ |
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static void |
create_key (void) |
{ |
int err; |
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err = pthread_key_create (&segment_list_key, free_segments); |
if (err != 0) |
{ |
static const char msg[] = "pthread_key_create failed: errno "; |
__morestack_fail (msg, sizeof msg - 1, err); |
} |
} |
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/* Pass information from the pthread_create wrapper to |
stack_split_initialize_thread. */ |
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struct pthread_create_args |
{ |
void *(*start_routine) (void *); |
void *arg; |
}; |
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/* Initialize a thread. This is called via pthread_create. It calls |
a target dependent function to set up any required stack guard. */ |
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static void* stack_split_initialize_thread (void *) |
__attribute__ ((no_split_stack)); |
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static void * |
stack_split_initialize_thread (void *varg) |
{ |
struct pthread_create_args *args = (struct pthread_create_args *) varg; |
int err; |
void *(*start_routine) (void *); |
void *arg; |
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__stack_split_initialize (); |
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err = pthread_setspecific (segment_list_key, (void *) &__morestack_segments); |
if (err != 0) |
{ |
static const char msg[] = "pthread_setspecific failed: errno "; |
__morestack_fail (msg, sizeof msg - 1, err); |
} |
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start_routine = args->start_routine; |
arg = args->arg; |
free (args); |
return (*start_routine) (arg); |
} |
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/* This function wraps calls to pthread_create to make sure that the |
stack guard is initialized for new threads. FIXME: This hack will |
not be necessary if glibc supports -fsplit-stack directly. */ |
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int __wrap_pthread_create (pthread_t *, const pthread_attr_t *, |
void *(*start_routine) (void *), void *) |
__attribute__ ((visibility ("hidden"))); |
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extern int __real_pthread_create (pthread_t *, const pthread_attr_t *, |
void *(*start_routine) (void *), void *) |
__attribute__ ((weak)); |
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int |
__wrap_pthread_create (pthread_t *tid, const pthread_attr_t *attr, |
void *(*start_routine) (void *), void *arg) |
{ |
int err; |
struct pthread_create_args* args; |
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err = pthread_once (&create_key_once, create_key); |
if (err != 0) |
{ |
static const char msg[] = "pthread_once failed: errno "; |
__morestack_fail (msg, sizeof msg - 1, err); |
} |
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args = malloc (sizeof (struct pthread_create_args)); |
if (args == NULL) |
return EAGAIN; |
args->start_routine = start_routine; |
args->arg = arg; |
return __real_pthread_create (tid, attr, stack_split_initialize_thread, args); |
} |
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#endif /* !defined (inhibit_libc) */ |