Merge branch '2523-checked-arithmetic' into 'main'

gtypes: Rework checked arithmetic handling

Closes #2523

See merge request GNOME/glib!2343
This commit is contained in:
Philip Withnall 2021-11-18 10:54:54 +00:00
commit 81a31fd062

View File

@ -424,56 +424,62 @@ typedef const gchar * (*GTranslateFunc) (const gchar *str,
/* https://bugzilla.gnome.org/show_bug.cgi?id=769104 */
#if __GNUC__ >= 5 && !defined(__INTEL_COMPILER)
#define _GLIB_HAVE_BUILTIN_OVERFLOW_CHECKS
#elif g_macro__has_builtin(__builtin_uadd_overflow)
#elif g_macro__has_builtin(__builtin_add_overflow)
#define _GLIB_HAVE_BUILTIN_OVERFLOW_CHECKS
#endif
#endif
#ifdef _GLIB_HAVE_BUILTIN_OVERFLOW_CHECKS
#define g_uint_checked_add(dest, a, b) \
_GLIB_CHECKED_ADD_U32(dest, a, b)
(!__builtin_add_overflow(a, b, dest))
#define g_uint_checked_mul(dest, a, b) \
_GLIB_CHECKED_MUL_U32(dest, a, b)
(!__builtin_mul_overflow(a, b, dest))
#define g_uint64_checked_add(dest, a, b) \
_GLIB_CHECKED_ADD_U64(dest, a, b)
(!__builtin_add_overflow(a, b, dest))
#define g_uint64_checked_mul(dest, a, b) \
_GLIB_CHECKED_MUL_U64(dest, a, b)
(!__builtin_mul_overflow(a, b, dest))
#if GLIB_SIZEOF_SIZE_T == 8
#define g_size_checked_add(dest, a, b) \
_GLIB_CHECKED_ADD_U64(dest, a, b)
(!__builtin_add_overflow(a, b, dest))
#define g_size_checked_mul(dest, a, b) \
_GLIB_CHECKED_MUL_U64(dest, a, b)
#else
#define g_size_checked_add(dest, a, b) \
_GLIB_CHECKED_ADD_U32(dest, a, b)
#define g_size_checked_mul(dest, a, b) \
_GLIB_CHECKED_MUL_U32(dest, a, b)
#endif
(!__builtin_mul_overflow(a, b, dest))
#else /* !_GLIB_HAVE_BUILTIN_OVERFLOW_CHECKS */
/* The names of the following inlines are private. Use the macro
* definitions above.
*/
#ifdef _GLIB_HAVE_BUILTIN_OVERFLOW_CHECKS
static inline gboolean _GLIB_CHECKED_ADD_U32 (guint32 *dest, guint32 a, guint32 b) {
return !__builtin_uadd_overflow(a, b, dest); }
static inline gboolean _GLIB_CHECKED_MUL_U32 (guint32 *dest, guint32 a, guint32 b) {
return !__builtin_umul_overflow(a, b, dest); }
static inline gboolean _GLIB_CHECKED_ADD_U64 (guint64 *dest, guint64 a, guint64 b) {
G_STATIC_ASSERT(sizeof (unsigned long long) == sizeof (guint64));
return !__builtin_uaddll_overflow(a, b, (unsigned long long *) dest); }
static inline gboolean _GLIB_CHECKED_MUL_U64 (guint64 *dest, guint64 a, guint64 b) {
return !__builtin_umulll_overflow(a, b, (unsigned long long *) dest); }
#else
static inline gboolean _GLIB_CHECKED_ADD_U32 (guint32 *dest, guint32 a, guint32 b) {
static inline gboolean _GLIB_CHECKED_ADD_UINT (guint *dest, guint a, guint b) {
*dest = a + b; return *dest >= a; }
static inline gboolean _GLIB_CHECKED_MUL_U32 (guint32 *dest, guint32 a, guint32 b) {
static inline gboolean _GLIB_CHECKED_MUL_UINT (guint *dest, guint a, guint b) {
*dest = a * b; return !a || *dest / a == b; }
static inline gboolean _GLIB_CHECKED_ADD_U64 (guint64 *dest, guint64 a, guint64 b) {
static inline gboolean _GLIB_CHECKED_ADD_UINT64 (guint64 *dest, guint64 a, guint64 b) {
*dest = a + b; return *dest >= a; }
static inline gboolean _GLIB_CHECKED_MUL_U64 (guint64 *dest, guint64 a, guint64 b) {
static inline gboolean _GLIB_CHECKED_MUL_UINT64 (guint64 *dest, guint64 a, guint64 b) {
*dest = a * b; return !a || *dest / a == b; }
#endif
static inline gboolean _GLIB_CHECKED_ADD_SIZE (gsize *dest, gsize a, gsize b) {
*dest = a + b; return *dest >= a; }
static inline gboolean _GLIB_CHECKED_MUL_SIZE (gsize *dest, gsize a, gsize b) {
*dest = a * b; return !a || *dest / a == b; }
#define g_uint_checked_add(dest, a, b) \
_GLIB_CHECKED_ADD_UINT(dest, a, b)
#define g_uint_checked_mul(dest, a, b) \
_GLIB_CHECKED_MUL_UINT(dest, a, b)
#define g_uint64_checked_add(dest, a, b) \
_GLIB_CHECKED_ADD_UINT64(dest, a, b)
#define g_uint64_checked_mul(dest, a, b) \
_GLIB_CHECKED_MUL_UINT64(dest, a, b)
#define g_size_checked_add(dest, a, b) \
_GLIB_CHECKED_ADD_SIZE(dest, a, b)
#define g_size_checked_mul(dest, a, b) \
_GLIB_CHECKED_MUL_SIZE(dest, a, b)
#endif /* !_GLIB_HAVE_BUILTIN_OVERFLOW_CHECKS */
/* IEEE Standard 754 Single Precision Storage Format (gfloat):
*