diff options
| -rw-r--r-- | ChangeLog | 7 | ||||
| -rw-r--r-- | include/libc-internal.h | 20 |
2 files changed, 27 insertions, 0 deletions
@@ -1,3 +1,10 @@ +2013-06-24 Mike Frysinger <vapier@gentoo.org> + + * include/libc-internal.h (ALIGN_DOWN): New helper macro. + (ALIGN_UP): Likewise. + (PTR_ALIGN_DOWN): Likewise. + (PTR_ALIGN_UP): Likewise. + 2013-06-24 Ryan S. Arnold <rsa@linux.vnet.ibm.com> * sysdeps/powerpc/dl-procinfo.c (_dl_powerpc_platforms): Add "power8" diff --git a/include/libc-internal.h b/include/libc-internal.h index 0c0fa02..78f82da 100644 --- a/include/libc-internal.h +++ b/include/libc-internal.h @@ -50,4 +50,24 @@ extern void __init_misc (int, char **, char **); /* Cast an integer or a pointer VAL to integer with proper type. */ # define cast_to_integer(val) ((__integer_if_pointer_type (val)) (val)) +/* Align a value by rounding down to closest size. + e.g. Using size of 4096, we get this behavior: + {4095, 4096, 4097} = {0, 4096, 4096}. */ +#define ALIGN_DOWN(base, size) ((base) & -((__typeof__ (base)) (size))) + +/* Align a value by rounding up to closest size. + e.g. Using size of 4096, we get this behavior: + {4095, 4096, 4097} = {4096, 4096, 8192}. + + Note: The size argument has side effects (expanded multiple times). */ +#define ALIGN_UP(base, size) ALIGN_DOWN ((base) + (size) - 1, (size)) + +/* Same as ALIGN_DOWN(), but automatically casts when base is a pointer. */ +#define PTR_ALIGN_DOWN(base, size) \ + ((__typeof__ (base)) ALIGN_DOWN ((uintptr_t) (base), (size))) + +/* Same as ALIGN_UP(), but automatically casts when base is a pointer. */ +#define PTR_ALIGN_UP(base, size) \ + ((__typeof__ (base)) ALIGN_UP ((uintptr_t) (base), (size))) + #endif /* _LIBC_INTERNAL */ |