diff options
Diffstat (limited to 'gcc-4.9/libgcc/config/i386/gthr-win32.h')
| -rw-r--r-- | gcc-4.9/libgcc/config/i386/gthr-win32.h | 786 |
1 files changed, 786 insertions, 0 deletions
diff --git a/gcc-4.9/libgcc/config/i386/gthr-win32.h b/gcc-4.9/libgcc/config/i386/gthr-win32.h new file mode 100644 index 000000000..c295fd5f1 --- /dev/null +++ b/gcc-4.9/libgcc/config/i386/gthr-win32.h @@ -0,0 +1,786 @@ +/* Threads compatibility routines for libgcc2 and libobjc. */ +/* Compile this one with gcc. */ + +/* Copyright (C) 1999-2014 Free Software Foundation, Inc. + Contributed by Mumit Khan <khan@xraylith.wisc.edu>. + +This file is part of GCC. + +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. + +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. + +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. + +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/>. */ + +#ifndef GCC_GTHR_WIN32_H +#define GCC_GTHR_WIN32_H + +/* Make sure CONST_CAST2 (origin in system.h) is declared. */ +#ifndef CONST_CAST2 +#define CONST_CAST2(TOTYPE,FROMTYPE,X) ((__extension__(union {FROMTYPE _q; TOTYPE _nq;})(X))._nq) +#endif + +/* Windows32 threads specific definitions. The windows32 threading model + does not map well into pthread-inspired gcc's threading model, and so + there are caveats one needs to be aware of. + + 1. The destructor supplied to __gthread_key_create is ignored for + generic x86-win32 ports. This will certainly cause memory leaks + due to unreclaimed eh contexts (sizeof (eh_context) is at least + 24 bytes for x86 currently). + + This memory leak may be significant for long-running applications + that make heavy use of C++ EH. + + However, Mingw runtime (version 0.3 or newer) provides a mechanism + to emulate pthreads key dtors; the runtime provides a special DLL, + linked in if -mthreads option is specified, that runs the dtors in + the reverse order of registration when each thread exits. If + -mthreads option is not given, a stub is linked in instead of the + DLL, which results in memory leak. Other x86-win32 ports can use + the same technique of course to avoid the leak. + + 2. The error codes returned are non-POSIX like, and cast into ints. + This may cause incorrect error return due to truncation values on + hw where sizeof (DWORD) > sizeof (int). + + 3. We are currently using a special mutex instead of the Critical + Sections, since Win9x does not support TryEnterCriticalSection + (while NT does). + + The basic framework should work well enough. In the long term, GCC + needs to use Structured Exception Handling on Windows32. */ + +#define __GTHREADS 1 + +#include <errno.h> +#ifdef __MINGW32__ +#include <_mingw.h> +#endif + +#ifndef __UNUSED_PARAM +#define __UNUSED_PARAM(x) x +#endif + +#ifdef _LIBOBJC + +/* This is necessary to prevent windef.h (included from windows.h) from + defining its own BOOL as a typedef. */ +#ifndef __OBJC__ +#define __OBJC__ +#endif +#include <windows.h> +/* Now undef the windows BOOL. */ +#undef BOOL + +/* Key structure for maintaining thread specific storage */ +static DWORD __gthread_objc_data_tls = (DWORD) -1; + +/* Backend initialization functions */ + +/* Initialize the threads subsystem. */ +int +__gthread_objc_init_thread_system (void) +{ + /* Initialize the thread storage key. */ + if ((__gthread_objc_data_tls = TlsAlloc ()) != (DWORD) -1) + return 0; + else + return -1; +} + +/* Close the threads subsystem. */ +int +__gthread_objc_close_thread_system (void) +{ + if (__gthread_objc_data_tls != (DWORD) -1) + TlsFree (__gthread_objc_data_tls); + return 0; +} + +/* Backend thread functions */ + +/* Create a new thread of execution. */ +objc_thread_t +__gthread_objc_thread_detach (void (*func)(void *arg), void *arg) +{ + DWORD thread_id = 0; + HANDLE win32_handle; + + if (!(win32_handle = CreateThread (NULL, 0, (LPTHREAD_START_ROUTINE) func, + arg, 0, &thread_id))) + thread_id = 0; + + return (objc_thread_t) (INT_PTR) thread_id; +} + +/* Set the current thread's priority. */ +int +__gthread_objc_thread_set_priority (int priority) +{ + int sys_priority = 0; + + switch (priority) + { + case OBJC_THREAD_INTERACTIVE_PRIORITY: + sys_priority = THREAD_PRIORITY_NORMAL; + break; + default: + case OBJC_THREAD_BACKGROUND_PRIORITY: + sys_priority = THREAD_PRIORITY_BELOW_NORMAL; + break; + case OBJC_THREAD_LOW_PRIORITY: + sys_priority = THREAD_PRIORITY_LOWEST; + break; + } + + /* Change priority */ + if (SetThreadPriority (GetCurrentThread (), sys_priority)) + return 0; + else + return -1; +} + +/* Return the current thread's priority. */ +int +__gthread_objc_thread_get_priority (void) +{ + int sys_priority; + + sys_priority = GetThreadPriority (GetCurrentThread ()); + + switch (sys_priority) + { + case THREAD_PRIORITY_HIGHEST: + case THREAD_PRIORITY_TIME_CRITICAL: + case THREAD_PRIORITY_ABOVE_NORMAL: + case THREAD_PRIORITY_NORMAL: + return OBJC_THREAD_INTERACTIVE_PRIORITY; + + default: + case THREAD_PRIORITY_BELOW_NORMAL: + return OBJC_THREAD_BACKGROUND_PRIORITY; + + case THREAD_PRIORITY_IDLE: + case THREAD_PRIORITY_LOWEST: + return OBJC_THREAD_LOW_PRIORITY; + } + + /* Couldn't get priority. */ + return -1; +} + +/* Yield our process time to another thread. */ +void +__gthread_objc_thread_yield (void) +{ + Sleep (0); +} + +/* Terminate the current thread. */ +int +__gthread_objc_thread_exit (void) +{ + /* exit the thread */ + ExitThread (__objc_thread_exit_status); + + /* Failed if we reached here */ + return -1; +} + +/* Returns an integer value which uniquely describes a thread. */ +objc_thread_t +__gthread_objc_thread_id (void) +{ + return (objc_thread_t) (INT_PTR) GetCurrentThreadId (); +} + +/* Sets the thread's local storage pointer. */ +int +__gthread_objc_thread_set_data (void *value) +{ + if (TlsSetValue (__gthread_objc_data_tls, value)) + return 0; + else + return -1; +} + +/* Returns the thread's local storage pointer. */ +void * +__gthread_objc_thread_get_data (void) +{ + DWORD lasterror; + void *ptr; + + lasterror = GetLastError (); + + ptr = TlsGetValue (__gthread_objc_data_tls); /* Return thread data. */ + + SetLastError (lasterror); + + return ptr; +} + +/* Backend mutex functions */ + +/* Allocate a mutex. */ +int +__gthread_objc_mutex_allocate (objc_mutex_t mutex) +{ + if ((mutex->backend = (void *) CreateMutex (NULL, 0, NULL)) == NULL) + return -1; + else + return 0; +} + +/* Deallocate a mutex. */ +int +__gthread_objc_mutex_deallocate (objc_mutex_t mutex) +{ + CloseHandle ((HANDLE) (mutex->backend)); + return 0; +} + +/* Grab a lock on a mutex. */ +int +__gthread_objc_mutex_lock (objc_mutex_t mutex) +{ + int status; + + status = WaitForSingleObject ((HANDLE) (mutex->backend), INFINITE); + if (status != WAIT_OBJECT_0 && status != WAIT_ABANDONED) + return -1; + else + return 0; +} + +/* Try to grab a lock on a mutex. */ +int +__gthread_objc_mutex_trylock (objc_mutex_t mutex) +{ + int status; + + status = WaitForSingleObject ((HANDLE) (mutex->backend), 0); + if (status != WAIT_OBJECT_0 && status != WAIT_ABANDONED) + return -1; + else + return 0; +} + +/* Unlock the mutex */ +int +__gthread_objc_mutex_unlock (objc_mutex_t mutex) +{ + if (ReleaseMutex ((HANDLE) (mutex->backend)) == 0) + return -1; + else + return 0; +} + +/* Backend condition mutex functions */ + +/* Allocate a condition. */ +int +__gthread_objc_condition_allocate (objc_condition_t __UNUSED_PARAM(condition)) +{ + /* Unimplemented. */ + return -1; +} + +/* Deallocate a condition. */ +int +__gthread_objc_condition_deallocate (objc_condition_t __UNUSED_PARAM(condition)) +{ + /* Unimplemented. */ + return -1; +} + +/* Wait on the condition */ +int +__gthread_objc_condition_wait (objc_condition_t __UNUSED_PARAM(condition), + objc_mutex_t __UNUSED_PARAM(mutex)) +{ + /* Unimplemented. */ + return -1; +} + +/* Wake up all threads waiting on this condition. */ +int +__gthread_objc_condition_broadcast (objc_condition_t __UNUSED_PARAM(condition)) +{ + /* Unimplemented. */ + return -1; +} + +/* Wake up one thread waiting on this condition. */ +int +__gthread_objc_condition_signal (objc_condition_t __UNUSED_PARAM(condition)) +{ + /* Unimplemented. */ + return -1; +} + +#else /* _LIBOBJC */ + +#ifdef __cplusplus +extern "C" { +#endif + +typedef unsigned long __gthread_key_t; + +typedef struct { + int done; + long started; +} __gthread_once_t; + +typedef struct { + long counter; + void *sema; +} __gthread_mutex_t; + +typedef struct { + long counter; + long depth; + unsigned long owner; + void *sema; +} __gthread_recursive_mutex_t; + +#define __GTHREAD_ONCE_INIT {0, -1} +#define __GTHREAD_MUTEX_INIT_FUNCTION __gthread_mutex_init_function +#define __GTHREAD_MUTEX_INIT_DEFAULT {-1, 0} +#define __GTHREAD_RECURSIVE_MUTEX_INIT_FUNCTION \ + __gthread_recursive_mutex_init_function +#define __GTHREAD_RECURSIVE_MUTEX_INIT_DEFAULT {-1, 0, 0, 0} + +#if defined (_WIN32) && !defined(__CYGWIN__) +#define MINGW32_SUPPORTS_MT_EH 1 +/* Mingw runtime >= v0.3 provides a magic variable that is set to nonzero + if -mthreads option was specified, or 0 otherwise. This is to get around + the lack of weak symbols in PE-COFF. */ +extern int _CRT_MT; +extern int __mingwthr_key_dtor (unsigned long, void (*) (void *)); +#endif /* _WIN32 && !__CYGWIN__ */ + +/* The Windows95 kernel does not export InterlockedCompareExchange. + This provides a substitute. When building apps that reference + gthread_mutex_try_lock, the __GTHREAD_I486_INLINE_LOCK_PRIMITIVES + macro must be defined if Windows95 is a target. Currently + gthread_mutex_try_lock is not referenced by libgcc or libstdc++. */ +#ifdef __GTHREAD_I486_INLINE_LOCK_PRIMITIVES +static inline long +__gthr_i486_lock_cmp_xchg(long *__dest, long __xchg, long __comperand) +{ + long result; + __asm__ __volatile__ ("\n\ + lock\n\ + cmpxchg{l} {%4, %1|%1, %4}\n" + : "=a" (result), "=m" (*__dest) + : "0" (__comperand), "m" (*__dest), "r" (__xchg) + : "cc"); + return result; +} +#define __GTHR_W32_InterlockedCompareExchange __gthr_i486_lock_cmp_xchg +#else /* __GTHREAD_I486_INLINE_LOCK_PRIMITIVES */ +#define __GTHR_W32_InterlockedCompareExchange InterlockedCompareExchange +#endif /* __GTHREAD_I486_INLINE_LOCK_PRIMITIVES */ + +static inline int +__gthread_active_p (void) +{ +#ifdef MINGW32_SUPPORTS_MT_EH + return _CRT_MT; +#else + return 1; +#endif +} + +#if __GTHREAD_HIDE_WIN32API + +/* The implementations are in config/i386/gthr-win32.c in libgcc.a. + Only stubs are exposed to avoid polluting the C++ namespace with + windows api definitions. */ + +extern int __gthr_win32_once (__gthread_once_t *, void (*) (void)); +extern int __gthr_win32_key_create (__gthread_key_t *, void (*) (void*)); +extern int __gthr_win32_key_delete (__gthread_key_t); +extern void * __gthr_win32_getspecific (__gthread_key_t); +extern int __gthr_win32_setspecific (__gthread_key_t, const void *); +extern void __gthr_win32_mutex_init_function (__gthread_mutex_t *); +extern int __gthr_win32_mutex_lock (__gthread_mutex_t *); +extern int __gthr_win32_mutex_trylock (__gthread_mutex_t *); +extern int __gthr_win32_mutex_unlock (__gthread_mutex_t *); +extern void + __gthr_win32_recursive_mutex_init_function (__gthread_recursive_mutex_t *); +extern int __gthr_win32_recursive_mutex_lock (__gthread_recursive_mutex_t *); +extern int + __gthr_win32_recursive_mutex_trylock (__gthread_recursive_mutex_t *); +extern int __gthr_win32_recursive_mutex_unlock (__gthread_recursive_mutex_t *); +extern void __gthr_win32_mutex_destroy (__gthread_mutex_t *); +extern int + __gthr_win32_recursive_mutex_destroy (__gthread_recursive_mutex_t *); + +static inline int +__gthread_once (__gthread_once_t *__once, void (*__func) (void)) +{ + if (__gthread_active_p ()) + return __gthr_win32_once (__once, __func); + else + return -1; +} + +static inline int +__gthread_key_create (__gthread_key_t *__key, void (*__dtor) (void *)) +{ + return __gthr_win32_key_create (__key, __dtor); +} + +static inline int +__gthread_key_delete (__gthread_key_t __key) +{ + return __gthr_win32_key_delete (__key); +} + +static inline void * +__gthread_getspecific (__gthread_key_t __key) +{ + return __gthr_win32_getspecific (__key); +} + +static inline int +__gthread_setspecific (__gthread_key_t __key, const void *__ptr) +{ + return __gthr_win32_setspecific (__key, __ptr); +} + +static inline void +__gthread_mutex_init_function (__gthread_mutex_t *__mutex) +{ + __gthr_win32_mutex_init_function (__mutex); +} + +static inline void +__gthread_mutex_destroy (__gthread_mutex_t *__mutex) +{ + __gthr_win32_mutex_destroy (__mutex); +} + +static inline int +__gthread_mutex_lock (__gthread_mutex_t *__mutex) +{ + if (__gthread_active_p ()) + return __gthr_win32_mutex_lock (__mutex); + else + return 0; +} + +static inline int +__gthread_mutex_trylock (__gthread_mutex_t *__mutex) +{ + if (__gthread_active_p ()) + return __gthr_win32_mutex_trylock (__mutex); + else + return 0; +} + +static inline int +__gthread_mutex_unlock (__gthread_mutex_t *__mutex) +{ + if (__gthread_active_p ()) + return __gthr_win32_mutex_unlock (__mutex); + else + return 0; +} + +static inline void +__gthread_recursive_mutex_init_function (__gthread_recursive_mutex_t *__mutex) +{ + __gthr_win32_recursive_mutex_init_function (__mutex); +} + +static inline int +__gthread_recursive_mutex_lock (__gthread_recursive_mutex_t *__mutex) +{ + if (__gthread_active_p ()) + return __gthr_win32_recursive_mutex_lock (__mutex); + else + return 0; +} + +static inline int +__gthread_recursive_mutex_trylock (__gthread_recursive_mutex_t *__mutex) +{ + if (__gthread_active_p ()) + return __gthr_win32_recursive_mutex_trylock (__mutex); + else + return 0; +} + +static inline int +__gthread_recursive_mutex_unlock (__gthread_recursive_mutex_t *__mutex) +{ + if (__gthread_active_p ()) + return __gthr_win32_recursive_mutex_unlock (__mutex); + else + return 0; +} + +static inline int +__gthread_recursive_mutex_destroy (__gthread_recursive_mutex_t *__mutex) +{ + return __gthr_win32_recursive_mutex_destroy (__mutex); +} + +#else /* ! __GTHREAD_HIDE_WIN32API */ + +#include <windows.h> +#include <errno.h> + +static inline int +__gthread_once (__gthread_once_t *__once, void (*__func) (void)) +{ + if (! __gthread_active_p ()) + return -1; + else if (__once == NULL || __func == NULL) + return EINVAL; + + if (! __once->done) + { + if (InterlockedIncrement (&(__once->started)) == 0) + { + (*__func) (); + __once->done = TRUE; + } + else + { + /* Another thread is currently executing the code, so wait for it + to finish; yield the CPU in the meantime. If performance + does become an issue, the solution is to use an Event that + we wait on here (and set above), but that implies a place to + create the event before this routine is called. */ + while (! __once->done) + Sleep (0); + } + } + + return 0; +} + +/* Windows32 thread local keys don't support destructors; this leads to + leaks, especially in threaded applications making extensive use of + C++ EH. Mingw uses a thread-support DLL to work-around this problem. */ +static inline int +__gthread_key_create (__gthread_key_t *__key, + void (*__dtor) (void *) __attribute__((unused))) +{ + int __status = 0; + DWORD __tls_index = TlsAlloc (); + if (__tls_index != 0xFFFFFFFF) + { + *__key = __tls_index; +#ifdef MINGW32_SUPPORTS_MT_EH + /* Mingw runtime will run the dtors in reverse order for each thread + when the thread exits. */ + __status = __mingwthr_key_dtor (*__key, __dtor); +#endif + } + else + __status = (int) GetLastError (); + return __status; +} + +static inline int +__gthread_key_delete (__gthread_key_t __key) +{ + return (TlsFree (__key) != 0) ? 0 : (int) GetLastError (); +} + +static inline void * +__gthread_getspecific (__gthread_key_t __key) +{ + DWORD __lasterror; + void *__ptr; + + __lasterror = GetLastError (); + + __ptr = TlsGetValue (__key); + + SetLastError (__lasterror); + + return __ptr; +} + +static inline int +__gthread_setspecific (__gthread_key_t __key, const void *__ptr) +{ + if (TlsSetValue (__key, CONST_CAST2(void *, const void *, __ptr)) != 0) + return 0; + else + return GetLastError (); +} + +static inline void +__gthread_mutex_init_function (__gthread_mutex_t *__mutex) +{ + __mutex->counter = -1; + __mutex->sema = CreateSemaphoreW (NULL, 0, 65535, NULL); +} + +static inline void +__gthread_mutex_destroy (__gthread_mutex_t *__mutex) +{ + CloseHandle ((HANDLE) __mutex->sema); +} + +static inline int +__gthread_mutex_lock (__gthread_mutex_t *__mutex) +{ + int __status = 0; + + if (__gthread_active_p ()) + { + if (InterlockedIncrement (&__mutex->counter) == 0 || + WaitForSingleObject (__mutex->sema, INFINITE) == WAIT_OBJECT_0) + __status = 0; + else + { + /* WaitForSingleObject returns WAIT_FAILED, and we can only do + some best-effort cleanup here. */ + InterlockedDecrement (&__mutex->counter); + __status = 1; + } + } + return __status; +} + +static inline int +__gthread_mutex_trylock (__gthread_mutex_t *__mutex) +{ + int __status = 0; + + if (__gthread_active_p ()) + { + if (__GTHR_W32_InterlockedCompareExchange (&__mutex->counter, 0, -1) < 0) + __status = 0; + else + __status = 1; + } + return __status; +} + +static inline int +__gthread_mutex_unlock (__gthread_mutex_t *__mutex) +{ + if (__gthread_active_p ()) + { + if (InterlockedDecrement (&__mutex->counter) >= 0) + return ReleaseSemaphore (__mutex->sema, 1, NULL) ? 0 : 1; + } + return 0; +} + +static inline void +__gthread_recursive_mutex_init_function (__gthread_recursive_mutex_t *__mutex) +{ + __mutex->counter = -1; + __mutex->depth = 0; + __mutex->owner = 0; + __mutex->sema = CreateSemaphoreW (NULL, 0, 65535, NULL); +} + +static inline int +__gthread_recursive_mutex_lock (__gthread_recursive_mutex_t *__mutex) +{ + if (__gthread_active_p ()) + { + DWORD __me = GetCurrentThreadId(); + if (InterlockedIncrement (&__mutex->counter) == 0) + { + __mutex->depth = 1; + __mutex->owner = __me; + } + else if (__mutex->owner == __me) + { + InterlockedDecrement (&__mutex->counter); + ++(__mutex->depth); + } + else if (WaitForSingleObject (__mutex->sema, INFINITE) == WAIT_OBJECT_0) + { + __mutex->depth = 1; + __mutex->owner = __me; + } + else + { + /* WaitForSingleObject returns WAIT_FAILED, and we can only do + some best-effort cleanup here. */ + InterlockedDecrement (&__mutex->counter); + return 1; + } + } + return 0; +} + +static inline int +__gthread_recursive_mutex_trylock (__gthread_recursive_mutex_t *__mutex) +{ + if (__gthread_active_p ()) + { + DWORD __me = GetCurrentThreadId(); + if (__GTHR_W32_InterlockedCompareExchange (&__mutex->counter, 0, -1) < 0) + { + __mutex->depth = 1; + __mutex->owner = __me; + } + else if (__mutex->owner == __me) + ++(__mutex->depth); + else + return 1; + } + return 0; +} + +static inline int +__gthread_recursive_mutex_unlock (__gthread_recursive_mutex_t *__mutex) +{ + if (__gthread_active_p ()) + { + --(__mutex->depth); + if (__mutex->depth == 0) + { + __mutex->owner = 0; + + if (InterlockedDecrement (&__mutex->counter) >= 0) + return ReleaseSemaphore (__mutex->sema, 1, NULL) ? 0 : 1; + } + } + return 0; +} + +static inline int +__gthread_recursive_mutex_destroy (__gthread_recursive_mutex_t *__mutex) +{ + CloseHandle ((HANDLE) __mutex->sema); + return 0; +} + +#endif /* __GTHREAD_HIDE_WIN32API */ + +#ifdef __cplusplus +} +#endif + +#endif /* _LIBOBJC */ + +#endif /* ! GCC_GTHR_WIN32_H */ |