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

   1 /* { dg-do compile } */
   2 /* { dg-require-effective-target bswap } */
   3 /* { dg-require-effective-target stdint_types } */
   4 /* { dg-options "-O2 -fdump-tree-bswap" } */
   5 /* { dg-additional-options "-march=z900" { target s390-*-* } } */
   6
   7 #include <stdint.h>
   8
   9 unsigned char data[2];
  10
  11 struct uint16_st {
  12   unsigned char u0, u1;
  13 };
  14
  15 uint32_t read_le16_1 (void)
  16 {
  17   return data[0] | (data[1] << 8);
  18 }
  19
  20 uint32_t read_le16_2 (struct uint16_st data)
  21 {
  22   return data.u0 | (data.u1 << 8);
  23 }
  24
  25 uint32_t read_le16_3 (unsigned char *data)
  26 {
  27   return *data | (*(data + 1) << 8);
  28 }
  29
  30 uint32_t read_be16_1 (void)
  31 {
  32   return data[1] | (data[0] << 8);
  33 }
  34
  35 uint32_t read_be16_2 (struct uint16_st data)
  36 {
  37   return data.u1 | (data.u0 << 8);
  38 }
  39
  40 uint32_t read_be16_3 (unsigned char *data)
  41 {
  42   return *(data + 1) | (*data << 8);
  43 }
  44
  45 typedef int HItype __attribute__ ((mode (HI)));
  46
  47 /* Test that detection of significant sign extension works correctly. This
  48    checks that unknown byte markers are set correctly in cast of cast.  */
  49
  50 HItype
  51 swap16 (HItype in)
  52 {
  53   return (HItype) (((in >> 0) & 0xFF) << 8)
  54                 | (((in >> 8) & 0xFF) << 0);
  55 }
  56
  57 /* { dg-final { scan-tree-dump-times "16 bit load in target endianness found at" 3 "bswap" } } */
  58 /* { dg-final { scan-tree-dump-times "16 bit bswap implementation found at" 4 "bswap" } } */