luc14n0/glib
1
0
Fork 0
mirror of https://gitlab.gnome.org/GNOME/glib.git synced 2025-04-03 14:23:07 +02:00
Code Issues Packages Projects Releases Wiki Activity

gmem: Add an inline definition of g_free() to automatically use g_free_sized()

Browse Source 
When using GCC we can take the advantage of __builtin_object_size() to
know the allocated size of a memory area, this generally only works when
some optimization level enabled (-O1 seems enough here) and can provide
us with memory size information for lower-level optimizations.
This commit is contained in:
Marco Trevisan (Treviño) 2023-02-03 12:14:22 +01:00 committed by Philip Withnall
parent ad464d5563
commit c580b5c2f4
2 changed files with 21 additions and 2 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

12
glib/gmem.c
View File

@ -223,11 +223,17 @@ g_realloc (gpointer mem,
* If you know the allocated size of @mem, calling g_free_sized() may be faster, * If you know the allocated size of @mem, calling g_free_sized() may be faster,
* depending on the libc implementation in use. * depending on the libc implementation in use.
* *
* Starting from GLib 2.78, this may happen automatically in case a GCC
* compatible compiler is used with some optimization level and the allocated
* size is known at compile time (see [documentation of
* `__builtin_object_size()`](https://gcc.gnu.org/onlinedocs/gcc/Object-Size-Checking.html)
* to understand its caveats).
*
* If @mem is %NULL it simply returns, so there is no need to check @mem * If @mem is %NULL it simply returns, so there is no need to check @mem
* against %NULL before calling this function. * against %NULL before calling this function.
*/ */
void void
g_free (gpointer mem) (g_free) (gpointer mem)
{ {
free (mem); free (mem);
TRACE(GLIB_MEM_FREE((void*) mem)); TRACE(GLIB_MEM_FREE((void*) mem));
@ -246,6 +252,10 @@ g_free (gpointer mem)
* allocated. @size is passed to this function to allow optimizations in the * allocated. @size is passed to this function to allow optimizations in the
* allocator. If you don’t know the allocation size, use g_free() instead. * allocator. If you don’t know the allocation size, use g_free() instead.
* *
* In case a GCC compatible compiler is used, this function may be used
* automatically via g_free() if the allocated size is known at compile time,
* since GLib 2.78.
*
* Since: 2.76 * Since: 2.76
*/ */
void void

11
glib/gmem.h
View File

@ -71,7 +71,7 @@ typedef struct _GMemVTable GMemVTable;
*/ */
GLIB_AVAILABLE_IN_ALL GLIB_AVAILABLE_IN_ALL
void g_free (gpointer mem); void (g_free) (gpointer mem);
GLIB_AVAILABLE_IN_2_76 GLIB_AVAILABLE_IN_2_76
void g_free_sized (gpointer mem, void g_free_sized (gpointer mem,
size_t size); size_t size);
@ -165,6 +165,15 @@ void g_aligned_free_sized (gpointer mem,
GLIB_AVAILABLE_MACRO_IN_2_34 GLIB_AVAILABLE_MACRO_IN_2_34
#endif /* __GNUC__ */ #endif /* __GNUC__ */
#if G_GNUC_CHECK_VERSION (4, 1) && GLIB_VERSION_MAX_ALLOWED >= GLIB_VERSION_2_78
#define g_free(mem) \
(__builtin_object_size ((mem), 0) != ((size_t) - 1)) ? \
g_free_sized (mem, __builtin_object_size ((mem), 0)) : (g_free) (mem)
#endif /* G_GNUC_CHECK_VERSION (4, 1) && && GLIB_VERSION_MAX_ALLOWED >= GLIB_VERSION_2_78 */
/** /**
* g_steal_pointer: * g_steal_pointer:
* @pp: (not nullable): a pointer to a pointer * @pp: (not nullable): a pointer to a pointer