diff options
| author | H.J. Lu <hjl.tools@gmail.com> | 2012-04-10 12:11:54 -0700 |
|---|---|---|
| committer | H.J. Lu <hjl.tools@gmail.com> | 2012-04-10 13:02:41 -0700 |
| commit | b46068fcf2e915d740dab7993253c0ec8f84fe5d (patch) | |
| tree | 123c3b44b0b211712d5d0bbd8a506db4f2998cf5 | |
| parent | 73d65cc3784b1413b017fed31550ec11e717e45b (diff) | |
| download | glibc-b46068fcf2e915d740dab7993253c0ec8f84fe5d.tar.gz glibc-b46068fcf2e915d740dab7993253c0ec8f84fe5d.tar.xz glibc-b46068fcf2e915d740dab7993253c0ec8f84fe5d.zip | |
Use __builtin_bswap32/64 in x86_64 <bits/byteswap.h>
| -rw-r--r-- | ChangeLog | 6 | ||||
| -rw-r--r-- | sysdeps/x86_64/bits/byteswap.h | 85 |
2 files changed, 59 insertions, 32 deletions
diff --git a/ChangeLog b/ChangeLog index 80b38fc2ac..d6c9964beb 100644 --- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,9 @@ +2012-04-10 H.J. Lu <hongjiu.lu@intel.com> + + * sysdeps/x86_64/bits/byteswap.h: Include <features.h>. + (__bswap_32): Use __builtin_bswap32 for GCC >= 4.2. + (__bswap_64): Use __builtin_bswap64 for GCC >= 4.2. + 2012-04-10 Siddhesh Poyarekar <siddhesh@redhat.com> * elf/dl-support.c (_dl_inhibit_cache): New variable. diff --git a/sysdeps/x86_64/bits/byteswap.h b/sysdeps/x86_64/bits/byteswap.h index d7e503c622..4178439334 100644 --- a/sysdeps/x86_64/bits/byteswap.h +++ b/sysdeps/x86_64/bits/byteswap.h @@ -23,6 +23,7 @@ #ifndef _BITS_BYTESWAP_H #define _BITS_BYTESWAP_H 1 +#include <features.h> #include <bits/wordsize.h> /* Swap bytes in 16 bit value. */ @@ -37,46 +38,60 @@ ((((x) & 0xff000000) >> 24) | (((x) & 0x00ff0000) >> 8) | \ (((x) & 0x0000ff00) << 8) | (((x) & 0x000000ff) << 24)) -#if defined __GNUC__ && __GNUC__ >= 2 -# if __WORDSIZE == 64 || (defined __i486__ || defined __pentium__ \ - || defined __pentiumpro__ || defined __pentium4__ \ - || defined __k8__ || defined __athlon__ \ - || defined __k6__ || defined __nocona__ \ - || defined __core2__ || defined __geode__ \ - || defined __amdfam10__) +#ifdef __GNUC__ +# if __GNUC_PREREQ (4, 2) +static __inline unsigned int +__bswap_32 (unsigned int __bsx) +{ + return __builtin_bswap32 (__bsx); +} +# elif __GNUC__ >= 2 +# if __WORDSIZE == 64 || (defined __i486__ || defined __pentium__ \ + || defined __pentiumpro__ || defined __pentium4__ \ + || defined __k8__ || defined __athlon__ \ + || defined __k6__ || defined __nocona__ \ + || defined __core2__ || defined __geode__ \ + || defined __amdfam10__) /* To swap the bytes in a word the i486 processors and up provide the `bswap' opcode. On i386 we have to use three instructions. */ -# define __bswap_32(x) \ - (__extension__ \ - ({ register unsigned int __v, __x = (x); \ - if (__builtin_constant_p (__x)) \ - __v = __bswap_constant_32 (__x); \ - else \ - __asm__ ("bswap %0" : "=r" (__v) : "0" (__x)); \ - __v; })) +# define __bswap_32(x) \ + (__extension__ \ + ({ register unsigned int __v, __x = (x); \ + if (__builtin_constant_p (__x)) \ + __v = __bswap_constant_32 (__x); \ + else \ + __asm__ ("bswap %0" : "=r" (__v) : "0" (__x)); \ + __v; })) +# else +# define __bswap_32(x) \ + (__extension__ \ + ({ register unsigned int __v, __x = (x); \ + if (__builtin_constant_p (__x)) \ + __v = __bswap_constant_32 (__x); \ + else \ + __asm__ ("rorw $8, %w0;" \ + "rorl $16, %0;" \ + "rorw $8, %w0" \ + : "=r" (__v) \ + : "0" (__x) \ + : "cc"); \ + __v; })) +# endif # else -# define __bswap_32(x) \ +# define __bswap_32(x) \ (__extension__ \ - ({ register unsigned int __v, __x = (x); \ - if (__builtin_constant_p (__x)) \ - __v = __bswap_constant_32 (__x); \ - else \ - __asm__ ("rorw $8, %w0;" \ - "rorl $16, %0;" \ - "rorw $8, %w0" \ - : "=r" (__v) \ - : "0" (__x) \ - : "cc"); \ - __v; })) + ({ register unsigned int __x = (x); __bswap_constant_32 (__x); })) # endif #else -# define __bswap_32(x) \ - (__extension__ \ - ({ register unsigned int __x = (x); __bswap_constant_32 (__x); })) +static __inline unsigned int +__bswap_32 (unsigned int __bsx) +{ + return __bswap_constant_32 (__bsx); +} #endif -#if defined __GNUC__ && __GNUC__ >= 2 +#if __GNUC_PREREQ (2, 0) /* Swap bytes in 64 bit value. */ # define __bswap_constant_64(x) \ (__extension__ ((((x) & 0xff00000000000000ull) >> 56) \ @@ -88,7 +103,13 @@ | (((x) & 0x000000000000ff00ull) << 40) \ | (((x) & 0x00000000000000ffull) << 56))) -# if __WORDSIZE == 64 +# if __GNUC_PREREQ (4, 2) +static __inline unsigned long long int +__bswap_64 (unsigned long long int __bsx) +{ + return __builtin_bswap64 (__bsx); +} +# elif __WORDSIZE == 64 # define __bswap_64(x) \ (__extension__ \ ({ register unsigned long __v, __x = (x); \ |