+2004-08-27 Jason Merrill <jason@redhat.com>
+
+ PR c++/13684
+ * gimplify.c (gimplify_cleanup_point_expr): Handle CLEANUP_EH_ONLY.
+ (gimple_push_cleanup): Add eh_only parm.
+ (gimplify_target_expr): Pass it.
+ * c.opt (-fno-threadsafe-statics): New option.
+ * c-opts.c (c_common_handle_option): Handle it.
+ * c-common.h (flag_threadsafe_statics): Declare it.
+ * c-common.c (flag_threadsafe_statics): Record it.
+ * doc/invoke.texi: Document it.
+ * tsystem.h (_GNU_SOURCE): Define.
+ * gthr-posix.h (__gthread_recursive_mutex_t): New typedef.
+ (__GTHREAD_RECURSIVE_MUTEX_INIT): New macro.
+ (__GTHREAD_RECURSIVE_MUTEX_INIT_FUNCTION): New macro.
+ (__gthread_recursive_mutex_init_function): New fn.
+ (__gthread_recursive_mutex_lock): New fn.
+ (__gthread_recursive_mutex_trylock): New fn.
+ (__gthread_recursive_mutex_unlock): New fn.
+ * gthr-solaris.h, gthr-single.h, gthr-dce.h: Likewise.
+ * gthr-win32.h, gthr-vxworks.h: Likewise.
+ * gthr.h: Document.
+
2004-08-27 David Edelsohn <edelsohn@gnu.org>
* config/rs6000/rs6000.c (rs6000_override_options): Increase
int flag_enforce_eh_specs = 1;
+/* Nonzero means to generate thread-safe code for initializing local
+ statics. */
+
+int flag_threadsafe_statics = 1;
+
/* Nonzero means warn about implicit declarations. */
int warn_implicit = 1;
extern int flag_enforce_eh_specs;
+/* Nonzero (the default) means to generate thread-safe code for
+ initializing local statics. */
+
+extern int flag_threadsafe_statics;
+
/* Nonzero means warn about implicit declarations. */
extern int warn_implicit;
flag_weak = value;
break;
+ case OPT_fthreadsafe_statics:
+ flag_threadsafe_statics = value;
+ break;
+
case OPT_fzero_link:
flag_zero_link = value;
break;
fthis-is-variable
C++ ObjC++
+fthreadsafe-statics
+C++ ObjC++
+-fno-threadsafe-statics Do not generate thread-safe code for initializing local statics.
+
funsigned-bitfields
C ObjC C++ ObjC++
When \"signed\" or \"unsigned\" is not given make the bitfield unsigned
else
return 0;
}
+
+void
+__gthr_win32_recursive_mutex_init_function (__gthread_recursive_mutex_t *mutex)
+{
+ mutex->counter = -1;
+ mutex->depth = 0;
+ mutex->owner = 0;
+ mutex->sema = CreateSemaphore (NULL, 0, 65535, NULL);
+}
+
+int
+__gthr_win32_recursive_mutex_lock (__gthread_recursive_mutex_t *mutex)
+{
+ DWORD me = GetCurrentThreadId();
+ if (InterlockedIncrement (&mutex->counter) == 0)
+ {
+ mutex->depth = 1;
+ mutex->owner = me;
+ }
+ else if (mutex->owner == me)
+ {
+ InterlockedDecrement (&mx->lock_idx);
+ ++(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;
+}
+
+int
+__gthr_win32_recursive_mutex_trylock (__gthread_recursive_mutex_t *mutex)
+{
+ 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;
+}
+
+int
+__gthr_win32_recursive_mutex_unlock (__gthread_recursive_mutex_t *mutex)
+{
+ --(mutex->depth);
+ if (mutex->depth == 0)
+ {
+ mutex->owner = 0;
+
+ if (InterlockedDecrement (&mutex->counter) >= 0)
+ return ReleaseSemaphore (mutex->sema, 1, NULL) ? 0 : 1;
+ }
+
+ return 0;
+}
+2004-08-27 Jason Merrill <jason@redhat.com>
+
+ PR c++/13684
+ * decl.c (expand_static_init): Use thread-safety API.
+ (register_dtor_fn): Return the call, don't expand it.
+ * tree.c (add_stmt_to_compound): New fn.
+ (stabilize_call): Use it.
+
2004-08-27 Richard Henderson <rth@redhat.com>
* cp-tree.def (OFFSETOF_EXPR): New.
extern int local_variable_p (tree);
extern int nonstatic_local_decl_p (tree);
extern tree declare_global_var (tree, tree);
-extern void register_dtor_fn (tree);
+extern tree register_dtor_fn (tree);
extern tmpl_spec_kind current_tmpl_spec_kind (int);
extern tree cp_fname_init (const char *, tree *);
extern tree builtin_function (const char *name, tree type,
extern tree stabilize_expr (tree, tree *);
extern void stabilize_call (tree, tree *);
extern bool stabilize_init (tree, tree *);
+extern tree add_stmt_to_compound (tree, tree);
extern tree cxx_maybe_build_cleanup (tree);
extern void init_tree (void);
extern int pod_type_p (tree);
/* Generate code to handle the destruction of DECL, an object with
static storage duration. */
-void
+tree
register_dtor_fn (tree decl)
{
tree cleanup;
tree fcall;
if (TYPE_HAS_TRIVIAL_DESTRUCTOR (TREE_TYPE (decl)))
- return;
+ return void_zero_node;
/* Call build_cleanup before we enter the anonymous function so that
any access checks will be done relative to the current scope,
}
else
args = tree_cons (NULL_TREE, cleanup, NULL_TREE);
- finish_expr_stmt (build_function_call (get_atexit_node (), args));
+ return build_function_call (get_atexit_node (), args);
}
/* DECL is a VAR_DECL with static storage duration. INIT, if present,
if (DECL_FUNCTION_SCOPE_P (decl))
{
/* Emit code to perform this initialization but once. */
- tree if_stmt;
- tree then_clause;
- tree assignment;
- tree guard;
- tree guard_init;
+ tree if_stmt, inner_if_stmt;
+ tree then_clause, inner_then_clause;
+ tree guard, guard_addr, guard_addr_list;
+ tree acquire_fn, release_fn, abort_fn;
+ tree flag, begin;
/* Emit code to perform this initialization but once. This code
looks like:
- static int guard = 0;
- if (!guard) {
- // Do initialization.
- guard = 1;
- // Register variable for destruction at end of program.
+ static <type> guard;
+ if (!guard.first_byte) {
+ if (__cxa_guard_acquire (&guard)) {
+ bool flag = false;
+ try {
+ // Do initialization.
+ flag = true; __cxa_guard_release (&guard);
+ // Register variable for destruction at end of program.
+ } catch {
+ if (!flag) __cxa_guard_abort (&guard);
+ }
}
- Note that the `temp' variable is only set to 1 *after* the
+ Note that the `flag' variable is only set to 1 *after* the
initialization is complete. This ensures that an exception,
thrown during the construction, will cause the variable to
reinitialized when we pass through this code again, as per:
[stmt.dcl]
- If the initialization exits by throwing an exception, the
+ If the initialization exits by throwing an exception, the
initialization is not complete, so it will be tried again
the next time control enters the declaration.
- In theory, this process should be thread-safe, too; multiple
- threads should not be able to initialize the variable more
- than once. We don't yet attempt to ensure thread-safety. */
+ This process should be thread-safe, too; multiple threads
+ should not be able to initialize the variable more than
+ once. */
/* Create the guard variable. */
guard = get_guard (decl);
/* Begin the conditional initialization. */
if_stmt = begin_if_stmt ();
finish_if_stmt_cond (get_guard_cond (guard), if_stmt);
- then_clause = begin_compound_stmt (0);
-
- /* Do the initialization itself. */
- assignment = init ? init : NULL_TREE;
-
- /* Once the assignment is complete, set TEMP to 1. Since the
- construction of the static object is complete at this point,
- we want to make sure TEMP is set to 1 even if a temporary
- constructed during the initialization throws an exception
- when it is destroyed. So, we combine the initialization and
- the assignment to TEMP into a single expression, ensuring
- that when we call finish_expr_stmt the cleanups will not be
- run until after TEMP is set to 1. */
- guard_init = set_guard (guard);
- if (assignment)
- assignment = build_compound_expr (assignment, guard_init);
+ then_clause = begin_compound_stmt (BCS_NO_SCOPE);
+
+ if (flag_threadsafe_statics)
+ {
+ guard_addr = build_address (guard);
+ guard_addr_list = build_tree_list (NULL_TREE, guard_addr);
+
+ acquire_fn = get_identifier ("__cxa_guard_acquire");
+ release_fn = get_identifier ("__cxa_guard_release");
+ abort_fn = get_identifier ("__cxa_guard_abort");
+ if (!get_global_value_if_present (acquire_fn, &acquire_fn))
+ {
+ tree argtypes = tree_cons (NULL_TREE, TREE_TYPE (guard_addr),
+ void_list_node);
+ tree vfntype = build_function_type (void_type_node, argtypes);
+ acquire_fn = push_library_fn
+ (acquire_fn, build_function_type (integer_type_node, argtypes));
+ release_fn = push_library_fn (release_fn, vfntype);
+ abort_fn = push_library_fn (abort_fn, vfntype);
+ }
+ else
+ {
+ release_fn = identifier_global_value (release_fn);
+ abort_fn = identifier_global_value (abort_fn);
+ }
+
+ inner_if_stmt = begin_if_stmt ();
+ finish_if_stmt_cond (build_call (acquire_fn, guard_addr_list),
+ inner_if_stmt);
+
+ inner_then_clause = begin_compound_stmt (BCS_NO_SCOPE);
+ begin = get_target_expr (boolean_false_node);
+ flag = TARGET_EXPR_SLOT (begin);
+
+ TARGET_EXPR_CLEANUP (begin)
+ = build (COND_EXPR, void_type_node, flag,
+ void_zero_node,
+ build_call (abort_fn, guard_addr_list));
+ CLEANUP_EH_ONLY (begin) = 1;
+
+ /* Do the initialization itself. */
+ init = add_stmt_to_compound (begin, init);
+ init = add_stmt_to_compound
+ (init, build (MODIFY_EXPR, void_type_node, flag, boolean_true_node));
+ init = add_stmt_to_compound
+ (init, build_call (release_fn, guard_addr_list));
+ }
else
- assignment = guard_init;
- finish_expr_stmt (assignment);
+ init = add_stmt_to_compound (init, set_guard (guard));
/* Use atexit to register a function for destroying this static
variable. */
- register_dtor_fn (decl);
+ init = add_stmt_to_compound (init, register_dtor_fn (decl));
+
+ finish_expr_stmt (init);
+
+ if (flag_threadsafe_statics)
+ {
+ finish_compound_stmt (inner_then_clause);
+ finish_then_clause (inner_if_stmt);
+ finish_if_stmt (inner_if_stmt);
+ }
finish_compound_stmt (then_clause);
finish_then_clause (if_stmt);
/* If we're using __cxa_atexit, register a a function that calls the
destructor for the object. */
if (flag_use_cxa_atexit)
- register_dtor_fn (decl);
+ finish_expr_stmt (register_dtor_fn (decl));
/* Finish up. */
finish_static_initialization_or_destruction (guard_if_stmt);
return exp;
}
+/* Add NEW, an expression whose value we don't care about, after the
+ similar expression ORIG. */
+
+tree
+add_stmt_to_compound (tree orig, tree new)
+{
+ if (!new || !TREE_SIDE_EFFECTS (new))
+ return orig;
+ if (!orig || !TREE_SIDE_EFFECTS (orig))
+ return new;
+ return build2 (COMPOUND_EXPR, void_type_node, orig, new);
+}
+
/* Like stabilize_expr, but for a call whose args we want to
pre-evaluate. */
{
tree init;
TREE_VALUE (t) = stabilize_expr (TREE_VALUE (t), &init);
- if (!init)
- /* Nothing. */;
- else if (inits)
- inits = build2 (COMPOUND_EXPR, void_type_node, inits, init);
- else
- inits = init;
+ inits = add_stmt_to_compound (inits, init);
}
*initp = inits;
-fno-nonansi-builtins -fno-operator-names @gol
-fno-optional-diags -fpermissive @gol
-frepo -fno-rtti -fstats -ftemplate-depth-@var{n} @gol
--fuse-cxa-atexit -fno-weak -nostdinc++ @gol
+-fno-threadsafe-statics -fuse-cxa-atexit -fno-weak -nostdinc++ @gol
-fno-default-inline -fvisibility-inlines-hidden @gol
-Wabi -Wctor-dtor-privacy @gol
-Wnon-virtual-dtor -Wreorder @gol
endless recursions during template class instantiation. ANSI/ISO C++
conforming programs must not rely on a maximum depth greater than 17.
+@item -fno-threadsafe-statics
+@opindex fno-threadsafe-statics
+Do not emit the extra code to use the routines specified in the C++
+ABI for thread-safe initialization of local statics. You can use this
+option to reduce code size slightly in code that doesn't need to be
+thread-safe.
+
@item -fuse-cxa-atexit
@opindex fuse-cxa-atexit
Register destructors for objects with static storage duration with the
else
{
tree sl, tfe;
+ enum tree_code code;
+
+ if (CLEANUP_EH_ONLY (wce))
+ code = TRY_CATCH_EXPR;
+ else
+ code = TRY_FINALLY_EXPR;
sl = tsi_split_statement_list_after (&iter);
- tfe = build (TRY_FINALLY_EXPR, void_type_node, sl, NULL_TREE);
+ tfe = build (code, void_type_node, sl, NULL_TREE);
append_to_statement_list (TREE_OPERAND (wce, 0),
&TREE_OPERAND (tfe, 1));
*wce_p = tfe;
is the cleanup action required. */
static void
-gimple_push_cleanup (tree var, tree cleanup, tree *pre_p)
+gimple_push_cleanup (tree var, tree cleanup, bool eh_only, tree *pre_p)
{
tree wce;
else
{
wce = build (WITH_CLEANUP_EXPR, void_type_node, cleanup);
+ CLEANUP_EH_ONLY (wce) = eh_only;
append_to_statement_list (wce, pre_p);
}
if (TARGET_EXPR_CLEANUP (targ))
{
gimplify_stmt (&TARGET_EXPR_CLEANUP (targ));
- gimple_push_cleanup (temp, TARGET_EXPR_CLEANUP (targ), pre_p);
+ gimple_push_cleanup (temp, TARGET_EXPR_CLEANUP (targ),
+ CLEANUP_EH_ONLY (targ), pre_p);
}
/* Only expand this once. */
-
+/* Threads compatibility routines for libgcc2 and libobjc. */
/* Compile this one with gcc. */
/* Copyright (C) 1997, 1999, 2000, 2001 Free Software Foundation, Inc.
typedef pthread_key_t __gthread_key_t;
typedef pthread_once_t __gthread_once_t;
typedef pthread_mutex_t __gthread_mutex_t;
+typedef pthread_mutex_t __gthread_recursive_mutex_t;
#define __GTHREAD_ONCE_INIT pthread_once_init
#define __GTHREAD_MUTEX_INIT_FUNCTION __gthread_mutex_init_function
+#define __GTHREAD_RECURSIVE_MUTEX_INIT_FUNCTION __gthread_recursive_mutex_init_function
#define __GTHREAD_MUTEX_INIT_DEFAULT pthread_once_init
return 0;
}
+static inline int
+__gthread_recursive_mutex_init_function (__gthread_recursive_mutex_t *mutex)
+{
+ if (__gthread_active_p ())
+ {
+ pthread_mutexattr_t attr;
+ int r;
+
+ r = pthread_mutexattr_create (&attr);
+ if (!r)
+ r = pthread_mutexattr_setkind_np (&attr, MUTEX_RECURSIVE_NP);
+ if (!r)
+ r = pthread_mutex_init (mutex, attr);
+ if (!r)
+ r = pthread_mutexattr_delete (&attr);
+ return r;
+ }
+}
+
+static inline int
+__gthread_recursive_mutex_lock (__gthread_recursive_mutex_t *mutex)
+{
+ return __gthread_mutex_lock (mutex);
+}
+
+static inline int
+__gthread_recursive_mutex_trylock (__gthread_recursive_mutex_t *mutex)
+{
+ return __gthread_mutex_trylock (mutex);
+}
+
+static inline int
+__gthread_recursive_mutex_unlock (__gthread_recursive_mutex_t *mutex)
+{
+ return __gthread_mutex_unlock (mutex);
+}
+
#endif /* _LIBOBJC */
#undef UNUSED
typedef pthread_key_t __gthread_key_t;
typedef pthread_once_t __gthread_once_t;
typedef pthread_mutex_t __gthread_mutex_t;
+typedef pthread_mutex_t __gthread_recursive_mutex_t;
#define __GTHREAD_MUTEX_INIT PTHREAD_MUTEX_INITIALIZER
#define __GTHREAD_ONCE_INIT PTHREAD_ONCE_INIT
+#if defined(PTHREAD_RECURSIVE_MUTEX_INITIALIZER)
+#define __GTHREAD_RECURSIVE_MUTEX_INIT PTHREAD_RECURSIVE_MUTEX_INITIALIZER
+#elif defined(PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP)
+#define __GTHREAD_RECURSIVE_MUTEX_INIT PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP
+#else
+#define __GTHREAD_RECURSIVE_MUTEX_INIT_FUNCTION __gthread_recursive_mutex_init_function
+#endif
#if SUPPORTS_WEAK && GTHREAD_USE_WEAK
return 0;
}
+#ifndef PTHREAD_RECURSIVE_MUTEX_INITIALIZER_NP
+static inline int
+__gthread_recursive_mutex_init_function (__gthread_recursive_mutex_t *mutex)
+{
+ if (__gthread_active_p ())
+ {
+ pthread_mutexattr_t attr;
+ int r;
+
+ r = pthread_mutexattr_init (&attr);
+ if (!r)
+ r = pthread_mutexattr_settype (&attr, PTHREAD_MUTEX_RECURSIVE);
+ if (!r)
+ r = pthread_mutex_init (mutex, &attr);
+ if (!r)
+ r = pthread_mutexattr_destroy (&attr);
+ return r;
+ }
+}
+#endif
+
+static inline int
+__gthread_recursive_mutex_lock (__gthread_recursive_mutex_t *mutex)
+{
+ return __gthread_mutex_lock (mutex);
+}
+
+static inline int
+__gthread_recursive_mutex_trylock (__gthread_recursive_mutex_t *mutex)
+{
+ return __gthread_mutex_trylock (mutex);
+}
+
+static inline int
+__gthread_recursive_mutex_unlock (__gthread_recursive_mutex_t *mutex)
+{
+ return __gthread_mutex_unlock (mutex);
+}
+
#endif /* _LIBOBJC */
#endif /* ! GCC_GTHR_POSIX_H */
/* Just provide compatibility for mutex handling. */
typedef int __gthread_mutex_t;
+typedef int __gthread_recursive_mutex_t;
#define __GTHREAD_MUTEX_INIT 0
return 0;
}
+static inline int
+__gthread_recursive_mutex_lock (__gthread_recursive_mutex_t *mutex)
+{
+ return __gthread_mutex_lock (mutex);
+}
+
+static inline int
+__gthread_recursive_mutex_trylock (__gthread_recursive_mutex_t *mutex)
+{
+ return __gthread_mutex_trylock (mutex);
+}
+
+static inline int
+__gthread_recursive_mutex_unlock (__gthread_recursive_mutex_t *mutex)
+{
+ return __gthread_mutex_unlock (mutex);
+}
+
#endif /* _LIBOBJC */
#undef UNUSED
int once;
} __gthread_once_t;
typedef mutex_t __gthread_mutex_t;
+typedef mutex_t __gthread_recursive_mutex_t;
#define __GTHREAD_ONCE_INIT { DEFAULTMUTEX, 0 }
#define __GTHREAD_MUTEX_INIT DEFAULTMUTEX
+#define __GTHREAD_RECURSIVE_MUTEX_INIT RECURSIVE_ERRORCHECKMUTEX
#if SUPPORTS_WEAK && GTHREAD_USE_WEAK
return 0;
}
+static inline int
+__gthread_recursive_mutex_lock (__gthread_recursive_mutex_t *mutex)
+{
+ return __gthread_mutex_lock (mutex);
+}
+
+static inline int
+__gthread_recursive_mutex_trylock (__gthread_recursive_mutex_t *mutex)
+{
+ return __gthread_mutex_trylock (mutex);
+}
+
+static inline int
+__gthread_recursive_mutex_unlock (__gthread_recursive_mutex_t *mutex)
+{
+ return __gthread_mutex_unlock (mutex);
+}
+
#endif /* _LIBOBJC */
#endif /* ! GCC_GTHR_SOLARIS_H */
#include <semLib.h>
typedef SEM_ID __gthread_mutex_t;
+/* All VxWorks mutexes are recursive. */
+typedef SEM_ID __gthread_recursive_mutex_t;
#define __GTHREAD_MUTEX_INIT_FUNCTION __gthread_mutex_init_function
+#define __GTHREAD_RECURSIVE_MUTEX_INIT_FUNCTION __gthread_recursive_mutex_init_function
static inline void
__gthread_mutex_init_function (__gthread_mutex_t *mutex)
return semGive (*mutex);
}
+static inline void
+__gthread_recursive_mutex_init_function (__gthread_recursive_mutex_t *mutex)
+{
+ __gthread_mutex_init_function (mutex);
+}
+
+static inline int
+__gthread_recursive_mutex_lock (__gthread_recursive_mutex_t *mutex)
+{
+ return __gthread_mutex_lock (mutex);
+}
+
+static inline int
+__gthread_recursive_mutex_trylock (__gthread_recursive_mutex_t *mutex)
+{
+ return __gthread_mutex_trylock (mutex);
+}
+
+static inline int
+__gthread_recursive_mutex_unlock (__gthread_recursive_mutex_t *mutex)
+{
+ return __gthread_mutex_unlock (mutex);
+}
+
/* pthread_once is complicated enough that it's implemented
out-of-line. See config/vxlib.c. */
void *sema;
} __gthread_mutex_t;
+typedef struct {
+ long counter;
+ long depth;
+ DWORD 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_mutex_init_function
+#define __GTHREAD_RECURSIVE_MUTEX_INIT_DEFAULT {-1, 0}
#if __MINGW32_MAJOR_VERSION >= 1 || \
(__MINGW32_MAJOR_VERSION == 0 && __MINGW32_MINOR_VERSION > 2)
return 0;
}
+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;
+}
+
#else /* ! __GTHREAD_HIDE_WIN32API */
#include <windows.h>
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 = CreateSemaphore (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 (&mx->lock_idx);
+ ++(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;
+}
+
#endif /* __GTHREAD_HIDE_WIN32API */
#ifdef __cplusplus
__gthread_key_t
__gthread_once_t
__gthread_mutex_t
+ __gthread_recursive_mutex_t
The threads interface must define the following macros:
function which looks like this:
void __GTHREAD_MUTEX_INIT_FUNCTION (__gthread_mutex_t *)
Don't define __GTHREAD_MUTEX_INIT in this case
+ __GTHREAD_RECURSIVE_MUTEX_INIT
+ __GTHREAD_RECURSIVE_MUTEX_INIT_FUNCTION
+ as above, but for a recursive mutex.
The threads interface must define the following static functions:
int __gthread_mutex_trylock (__gthread_mutex_t *mutex);
int __gthread_mutex_unlock (__gthread_mutex_t *mutex);
+ int __gthread_recursive_mutex_lock (__gthread_recursive_mutex_t *mutex);
+ int __gthread_recursive_mutex_trylock (__gthread_recursive_mutex_t *mutex);
+ int __gthread_recursive_mutex_unlock (__gthread_recursive_mutex_t *mutex);
+
All functions returning int should return zero on success or the error
number. If the operation is not supported, -1 is returned.
#define HAVE_DECL_GETOPT 1
#endif
+/* We want everything from the glibc headers. */
+#define _GNU_SOURCE 1
+
/* GCC supplies these headers. */
#include <stddef.h>
#include <float.h>
+2004-08-27 Jason Merrill <jason@redhat.com>
+
+ PR c++/13684
+ * libsupc++/guard.cc (static_mutex): Internal class implementing a
+ recursive mutex which controls initialization of local statics.
+ (__gnu_cxx::recursive_init): New exception class.
+ (__cxa_guard_acquire): Deal with locking and recursion detection.
+ (acquire_1, __cxa_guard_abort, __cxa_guard_release): Likewise.
+
2004-08-27 Matthias Klose <doko@debian.org>
* configure.host: For mips*-*-linux* update cpu_include_dir
// Written by Mark Mitchell, CodeSourcery LLC, <mark@codesourcery.com>
#include <cxxabi.h>
+#include <exception>
+#include <bits/c++config.h>
+#include <bits/gthr.h>
// The IA64/generic ABI uses the first byte of the guard variable.
// The ARM EABI uses the least significant bit.
+// Thread-safe static local initialization support.
+#ifdef __GTHREADS
+namespace
+{
+ // static_mutex is a single mutex controlling all static initializations.
+ // This is a static class--the need for a static initialization function
+ // to pass to __gthread_once precludes creating multiple instances, though
+ // I suppose you could achieve the same effect with a template.
+ class static_mutex
+ {
+ static __gthread_recursive_mutex_t mutex;
+
+#ifdef __GTHREAD_RECURSIVE_MUTEX_INIT_FUNCTION
+ static void init();
+#endif
+
+ public:
+ static void lock();
+ static void unlock();
+ };
+
+ __gthread_recursive_mutex_t static_mutex::mutex
+#ifdef __GTHREAD_RECURSIVE_MUTEX_INIT
+ = __GTHREAD_RECURSIVE_MUTEX_INIT
+#endif
+ ;
+
+#ifdef __GTHREAD_RECURSIVE_MUTEX_INIT_FUNCTION
+ void static_mutex::init()
+ {
+ __GTHREAD_RECURSIVE_MUTEX_INIT_FUNCTION (&mutex);
+ }
+#endif
+
+ void static_mutex::lock()
+ {
+#ifdef __GTHREAD_RECURSIVE_MUTEX_INIT_FUNCTION
+ static __gthread_once_t once = __GTHREAD_ONCE_INIT;
+ __gthread_once (&once, init);
+#endif
+ __gthread_recursive_mutex_lock (&mutex);
+ }
+
+ void static_mutex::unlock ()
+ {
+ __gthread_recursive_mutex_unlock (&mutex);
+ }
+}
+#endif
+
+namespace __gnu_cxx
+{
+ // 6.7[stmt.dcl]/4: If control re-enters the declaration (recursively)
+ // while the object is being initialized, the behavior is undefined.
+
+ // Since we already have a library function to handle locking, we might
+ // as well check for this situation and throw an exception.
+ // We use the second byte of the guard variable to remember that we're
+ // in the middle of an initialization.
+ class recursive_init: public std::exception
+ {
+ public:
+ recursive_init() throw() { }
+ virtual ~recursive_init() throw ();
+ };
+
+ recursive_init::~recursive_init() throw() { }
+}
+
namespace __cxxabiv1
{
+ static int
+ acquire_1 (__guard *g)
+ {
+ if (_GLIBCXX_GUARD_ACQUIRE (g))
+ {
+ if (((char *)g)[1]++)
+ {
+#ifdef __EXCEPTIONS
+ throw __gnu_cxx::recursive_init();
+#else
+ abort ();
+#endif
+ }
+ return 1;
+ }
+ return 0;
+ }
+
extern "C"
int __cxa_guard_acquire (__guard *g)
{
- return _GLIBCXX_GUARD_ACQUIRE (g);
+#ifdef __GTHREADS
+ if (__gthread_active_p ())
+ {
+ // Simple wrapper for exception safety.
+ struct mutex_wrapper
+ {
+ bool unlock;
+ mutex_wrapper (): unlock(true)
+ {
+ static_mutex::lock ();
+ }
+ ~mutex_wrapper ()
+ {
+ if (unlock)
+ static_mutex::unlock ();
+ }
+ } mw;
+
+ if (acquire_1 (g))
+ {
+ mw.unlock = false;
+ return 1;
+ }
+
+ return 0;
+ }
+#endif
+
+ return acquire_1 (g);
}
extern "C"
- void __cxa_guard_release (__guard *g)
+ void __cxa_guard_abort (__guard *g)
{
- _GLIBCXX_GUARD_RELEASE (g);
+ ((char *)g)[1]--;
+#ifdef __GTHREADS
+ if (__gthread_active_p ())
+ static_mutex::unlock ();
+#endif
}
extern "C"
- void __cxa_guard_abort (__guard *)
+ void __cxa_guard_release (__guard *g)
{
+ ((char *)g)[1]--;
+ _GLIBCXX_GUARD_RELEASE (g);
+#ifdef __GTHREADS
+ if (__gthread_active_p ())
+ static_mutex::unlock ();
+#endif
}
}
OSDN Git Service
