From 0253580a75decdaf22b6abce60d8265b2adb7dea Mon Sep 17 00:00:00 2001 From: Adhemerval Zanella Date: Fri, 21 Dec 2018 09:49:37 -0200 Subject: Replace check_mul_overflow_size_t with __builtin_mul_overflow Checked on x86_64-linux-gnu and i686-linux-gnu. * malloc/alloc_buffer_alloc_array.c (__libc_alloc_buffer_alloc_array): Use __builtin_mul_overflow in place of check_mul_overflow_size_t. * malloc/dynarray_emplace_enlarge.c (__libc_dynarray_emplace_enlarge): Likewise. * malloc/dynarray_resize.c (__libc_dynarray_resize): Likewise. * malloc/reallocarray.c (__libc_reallocarray): Likewise. * malloc/malloc-internal.h (check_mul_overflow_size_t): Remove function. * support/blob_repeat.c (check_mul_overflow_size_t, (minimum_stride_size, support_blob_repeat_allocate): Likewise. --- ChangeLog | 13 +++++++++++++ malloc/alloc_buffer_alloc_array.c | 3 +-- malloc/dynarray_emplace_enlarge.c | 3 +-- malloc/dynarray_resize.c | 3 +-- malloc/malloc-internal.h | 20 -------------------- malloc/reallocarray.c | 6 ++---- support/blob_repeat.c | 26 +++----------------------- 7 files changed, 21 insertions(+), 53 deletions(-) diff --git a/ChangeLog b/ChangeLog index 241f621..86d978c 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,16 @@ +2018-12-28 Adhemerval Zanella + + * malloc/alloc_buffer_alloc_array.c (__libc_alloc_buffer_alloc_array): + Use __builtin_mul_overflow in place of check_mul_overflow_size_t. + * malloc/dynarray_emplace_enlarge.c (__libc_dynarray_emplace_enlarge): + Likewise. + * malloc/dynarray_resize.c (__libc_dynarray_resize): Likewise. + * malloc/reallocarray.c (__libc_reallocarray): Likewise. + * malloc/malloc-internal.h (check_mul_overflow_size_t): Remove + function. + * support/blob_repeat.c (check_mul_overflow_size_t, + (minimum_stride_size, support_blob_repeat_allocate): Likewise. + 2018-12-28 Aurelien Jarno * sysdeps/alpha/fpu/libm-test-ulps: Regenerated. diff --git a/malloc/alloc_buffer_alloc_array.c b/malloc/alloc_buffer_alloc_array.c index 1dd098a..7505422 100644 --- a/malloc/alloc_buffer_alloc_array.c +++ b/malloc/alloc_buffer_alloc_array.c @@ -17,7 +17,6 @@ . */ #include -#include #include void * @@ -28,7 +27,7 @@ __libc_alloc_buffer_alloc_array (struct alloc_buffer *buf, size_t element_size, /* The caller asserts that align is a power of two. */ size_t aligned = ALIGN_UP (current, align); size_t size; - bool overflow = check_mul_overflow_size_t (element_size, count, &size); + bool overflow = __builtin_mul_overflow (element_size, count, &size); size_t new_current = aligned + size; if (!overflow /* Multiplication did not overflow. */ && aligned >= current /* No overflow in align step. */ diff --git a/malloc/dynarray_emplace_enlarge.c b/malloc/dynarray_emplace_enlarge.c index 0408271..aa8f5fa 100644 --- a/malloc/dynarray_emplace_enlarge.c +++ b/malloc/dynarray_emplace_enlarge.c @@ -18,7 +18,6 @@ #include #include -#include #include #include @@ -52,7 +51,7 @@ __libc_dynarray_emplace_enlarge (struct dynarray_header *list, } size_t new_size; - if (check_mul_overflow_size_t (new_allocated, element_size, &new_size)) + if (__builtin_mul_overflow (new_allocated, element_size, &new_size)) return false; void *new_array; if (list->array == scratch) diff --git a/malloc/dynarray_resize.c b/malloc/dynarray_resize.c index 0bfca1b..0205cf7 100644 --- a/malloc/dynarray_resize.c +++ b/malloc/dynarray_resize.c @@ -18,7 +18,6 @@ #include #include -#include #include #include @@ -38,7 +37,7 @@ __libc_dynarray_resize (struct dynarray_header *list, size_t size, over-allocation here. */ size_t new_size_bytes; - if (check_mul_overflow_size_t (size, element_size, &new_size_bytes)) + if (__builtin_mul_overflow (size, element_size, &new_size_bytes)) { /* Overflow. */ __set_errno (ENOMEM); diff --git a/malloc/malloc-internal.h b/malloc/malloc-internal.h index 9cee0fb..70d5b38 100644 --- a/malloc/malloc-internal.h +++ b/malloc/malloc-internal.h @@ -74,24 +74,4 @@ void __malloc_fork_unlock_child (void) attribute_hidden; /* Called as part of the thread shutdown sequence. */ void __malloc_arena_thread_freeres (void) attribute_hidden; -/* Set *RESULT to LEFT * RIGHT. Return true if the multiplication - overflowed. */ -static inline bool -check_mul_overflow_size_t (size_t left, size_t right, size_t *result) -{ -#if __GNUC__ >= 5 - return __builtin_mul_overflow (left, right, result); -#else - /* size_t is unsigned so the behavior on overflow is defined. */ - *result = left * right; - size_t half_size_t = ((size_t) 1) << (8 * sizeof (size_t) / 2); - if (__glibc_unlikely ((left | right) >= half_size_t)) - { - if (__glibc_unlikely (right != 0 && *result / right != left)) - return true; - } - return false; -#endif -} - #endif /* _MALLOC_INTERNAL_H */ diff --git a/malloc/reallocarray.c b/malloc/reallocarray.c index 319eccd..3264230 100644 --- a/malloc/reallocarray.c +++ b/malloc/reallocarray.c @@ -18,19 +18,17 @@ #include #include -#include void * __libc_reallocarray (void *optr, size_t nmemb, size_t elem_size) { size_t bytes; - if (check_mul_overflow_size_t (nmemb, elem_size, &bytes)) + if (__builtin_mul_overflow (nmemb, elem_size, &bytes)) { __set_errno (ENOMEM); return 0; } - else - return realloc (optr, bytes); + return realloc (optr, bytes); } libc_hidden_def (__libc_reallocarray) diff --git a/support/blob_repeat.c b/support/blob_repeat.c index 718846d..daa1b7f 100644 --- a/support/blob_repeat.c +++ b/support/blob_repeat.c @@ -34,26 +34,6 @@ optimization because mappings carry a lot of overhead. */ static const size_t maximum_small_size = 4 * 1024 * 1024; -/* Set *RESULT to LEFT * RIGHT. Return true if the multiplication - overflowed. See . */ -static inline bool -check_mul_overflow_size_t (size_t left, size_t right, size_t *result) -{ -#if __GNUC__ >= 5 - return __builtin_mul_overflow (left, right, result); -#else - /* size_t is unsigned so the behavior on overflow is defined. */ - *result = left * right; - size_t half_size_t = ((size_t) 1) << (8 * sizeof (size_t) / 2); - if (__glibc_unlikely ((left | right) >= half_size_t)) - { - if (__glibc_unlikely (right != 0 && *result / right != left)) - return true; - } - return false; -#endif -} - /* Internal helper for fill. */ static void fill0 (char *target, const char *element, size_t element_size, @@ -138,8 +118,8 @@ minimum_stride_size (size_t page_size, size_t element_size) common multiple, it appears only once. Therefore, shift one factor. */ size_t multiple; - if (check_mul_overflow_size_t (page_size >> common_zeros, element_size, - &multiple)) + if (__builtin_mul_overflow (page_size >> common_zeros, element_size, + &multiple)) return 0; return multiple; } @@ -275,7 +255,7 @@ support_blob_repeat_allocate (const void *element, size_t element_size, size_t count) { size_t total_size; - if (check_mul_overflow_size_t (element_size, count, &total_size)) + if (__builtin_mul_overflow (element_size, count, &total_size)) { errno = EOVERFLOW; return (struct support_blob_repeat) { 0 }; -- cgit v1.1