util.c: for aligned_malloc, store original pointer directly

diff --git a/src/util.c b/src/util.c
index 928a0368668ce06bd4a3236018c707148ffe4068..e0c5cc1bbc94ec0421bfd6184ee4834495c6f1e0 100644 (file)
--- a/src/util.c
+++ b/src/util.c
@@ -105,18 +105,13 @@ wimlib_wcsdup(const wchar_t *str)
 void *
 wimlib_aligned_malloc(size_t size, size_t alignment)
 {
-       wimlib_assert(alignment != 0 && is_power_of_2(alignment) &&
-                     alignment <= 4096);
-
-       const uintptr_t mask = alignment - 1;
-       char *ptr = NULL;
-       char *raw_ptr;
-
-       raw_ptr = MALLOC(mask + sizeof(size_t) + size);
-       if (raw_ptr) {
-               ptr = (char *)raw_ptr + sizeof(size_t);
-               ptr = (void *)(((uintptr_t)ptr + mask) & ~mask);
-               *((size_t *)ptr - 1) = ptr - raw_ptr;
+       wimlib_assert(is_power_of_2(alignment));
+
+       void *ptr = MALLOC(sizeof(void *) + alignment - 1 + size);
+       if (ptr) {
+               void *orig_ptr = ptr;
+               ptr = (void *)ALIGN((uintptr_t)ptr + sizeof(void *), alignment);
+               ((void **)ptr)[-1] = orig_ptr;
        }
        return ptr;
 }
@@ -125,7 +120,7 @@ void
 wimlib_aligned_free(void *ptr)
 {
        if (ptr)
-               FREE((char *)ptr - *((size_t *)ptr - 1));
+               FREE(((void **)ptr)[-1]);
 }
 
 void *