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| author | Yufeng Zhang <yufeng.zhang@arm.com> | 2014-04-22 17:26:59 +0100 |
|---|---|---|
| committer | Marcus Shawcroft <marcus.shawcroft@arm.com> | 2014-04-22 17:26:59 +0100 |
| commit | ea6c92f3be6d59736ee6183a61c538e5d1cc46f8 (patch) | |
| tree | 0ad25404aa0f39cdbdd7ca401cb0e472f0195893 | |
| parent | 766c4a363d5487dde04bb5e968c3db8b383ec3c2 (diff) | |
| download | glibc-ea6c92f3be6d59736ee6183a61c538e5d1cc46f8.tar.gz glibc-ea6c92f3be6d59736ee6183a61c538e5d1cc46f8.tar.xz glibc-ea6c92f3be6d59736ee6183a61c538e5d1cc46f8.zip | |
[AArch64] Use GCC builtins to count leading/tailing zeros.
| -rw-r--r-- | ChangeLog | 5 | ||||
| -rw-r--r-- | stdlib/longlong.h | 16 |
2 files changed, 21 insertions, 0 deletions
diff --git a/ChangeLog b/ChangeLog index 8c0f2a266d..c3fa6e57af 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,8 @@ +2014-04-22 Yufeng Zhang <yufeng.zhang@arm.com> + + * stdlib/longlong.h (count_leading_zeros, count_trailing_zeros) + (COUNT_LEADING_ZEROS_0): Define for AArch64. + 2014-04-22 Siddhesh Poyarekar <siddhesh@redhat.com> * nptl/sysdeps/unix/sysv/linux/sem_trywait.c: Include atomic.h. diff --git a/stdlib/longlong.h b/stdlib/longlong.h index 10d76cf65e..d45dbe2b73 100644 --- a/stdlib/longlong.h +++ b/stdlib/longlong.h @@ -122,6 +122,22 @@ extern const UQItype __clz_tab[256] attribute_hidden; #define __AND_CLOBBER_CC , "cc" #endif /* __GNUC__ < 2 */ +#if defined (__aarch64__) + +#if W_TYPE_SIZE == 32 +#define count_leading_zeros(COUNT, X) ((COUNT) = __builtin_clz (X)) +#define count_trailing_zeros(COUNT, X) ((COUNT) = __builtin_ctz (X)) +#define COUNT_LEADING_ZEROS_0 32 +#endif /* W_TYPE_SIZE == 32 */ + +#if W_TYPE_SIZE == 64 +#define count_leading_zeros(COUNT, X) ((COUNT) = __builtin_clzll (X)) +#define count_trailing_zeros(COUNT, X) ((COUNT) = __builtin_ctzll (X)) +#define COUNT_LEADING_ZEROS_0 64 +#endif /* W_TYPE_SIZE == 64 */ + +#endif /* __aarch64__ */ + #if defined (__alpha) && W_TYPE_SIZE == 64 #define umul_ppmm(ph, pl, m0, m1) \ do { \ |