From ea6c92f3be6d59736ee6183a61c538e5d1cc46f8 Mon Sep 17 00:00:00 2001 From: Yufeng Zhang Date: Tue, 22 Apr 2014 17:26:59 +0100 Subject: [PATCH] [AArch64] Use GCC builtins to count leading/tailing zeros. --- ChangeLog | 5 +++++ stdlib/longlong.h | 16 ++++++++++++++++ 2 files changed, 21 insertions(+) diff --git a/ChangeLog b/ChangeLog index 8c0f2a2..c3fa6e5 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,8 @@ +2014-04-22 Yufeng Zhang + + * stdlib/longlong.h (count_leading_zeros, count_trailing_zeros) + (COUNT_LEADING_ZEROS_0): Define for AArch64. + 2014-04-22 Siddhesh Poyarekar * nptl/sysdeps/unix/sysv/linux/sem_trywait.c: Include atomic.h. diff --git a/stdlib/longlong.h b/stdlib/longlong.h index 10d76cf..d45dbe2 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 { \ -- 2.7.4