gcc/testsuite/gcc.dg/optimize-bswapdi-1.c

   1 /* { dg-do compile { target alpha*-*-* ia64*-*-* x86_64-*-* s390x-*-* } } */
   2 /* { dg-require-effective-target stdint_types } */
   3 /* { dg-require-effective-target lp64 } */
   4 /* { dg-options "-O2 -fdump-tree-bswap" } */
   5
   6 #include <stdint.h>
   7 #define __const_swab64(x) ((uint64_t)(                                          \
   8         (((uint64_t)(x) & (uint64_t)0x00000000000000ffULL) << 56) |             \
   9         (((uint64_t)(x) & (uint64_t)0x000000000000ff00ULL) << 40) |             \
  10         (((uint64_t)(x) & (uint64_t)0x0000000000ff0000ULL) << 24) |             \
  11         (((uint64_t)(x) & (uint64_t)0x00000000ff000000ULL) <<  8) |             \
  12         (((uint64_t)(x) & (uint64_t)0x000000ff00000000ULL) >>  8) |             \
  13         (((uint64_t)(x) & (uint64_t)0x0000ff0000000000ULL) >> 24) |             \
  14         (((uint64_t)(x) & (uint64_t)0x00ff000000000000ULL) >> 40) |             \
  15         (((uint64_t)(x) & (uint64_t)0xff00000000000000ULL) >> 56)))
  16
  17
  18 /* This byte swap implementation is used by the Linux kernel and the
  19    GNU C library.  */
  20
  21 uint64_t
  22 swap64 (uint64_t in)
  23 {
  24   return __const_swab64 (in);
  25 }
  26
  27 /* This variant is currently used by libgcc.  The difference is that
  28    the bswap source and destination have a signed integer type which
  29    requires a slightly higher search depth in order to dive through
  30    the cast as well.  */
  31
  32 typedef int DItype __attribute__ ((mode (DI)));
  33 DItype
  34 swap64_b (DItype u)
  35 {
  36   return ((((u) & 0xff00000000000000ull) >> 56)
  37           | (((u) & 0x00ff000000000000ull) >> 40)
  38           | (((u) & 0x0000ff0000000000ull) >> 24)
  39           | (((u) & 0x000000ff00000000ull) >>  8)
  40           | (((u) & 0x00000000ff000000ull) <<  8)
  41           | (((u) & 0x0000000000ff0000ull) << 24)
  42           | (((u) & 0x000000000000ff00ull) << 40)
  43           | (((u) & 0x00000000000000ffull) << 56));
  44 }
  45
  46
  47 /* { dg-final { scan-tree-dump-times "64 bit bswap implementation found at" 2 "bswap" } } */
  48 /* { dg-final { cleanup-tree-dump "bswap" } } */