gcc/testsuite/gcc.c-torture/execute/bswap-2.c

   1 #ifdef __UINT32_TYPE__
   2 typedef __UINT32_TYPE__ uint32_t;
   3 #else
   4 typedef __UINT32_TYPE__ unsigned;
   5 #endif
   6
   7 struct bitfield {
   8   unsigned char f0:7;
   9   unsigned char   :1;
  10   unsigned char f1:7;
  11   unsigned char   :1;
  12   unsigned char f2:7;
  13   unsigned char   :1;
  14   unsigned char f3:7;
  15 };
  16
  17 struct ok {
  18   unsigned char f0;
  19   unsigned char f1;
  20   unsigned char f2;
  21   unsigned char f3;
  22 };
  23
  24 union bf_or_uint32 {
  25   struct ok inval;
  26   struct bitfield bfval;
  27 };
  28
  29 __attribute__ ((noinline, noclone)) uint32_t
  30 partial_read_le32 (union bf_or_uint32 in)
  31 {
  32   return in.bfval.f0 | (in.bfval.f1 << 8)
  33          | (in.bfval.f2 << 16) | (in.bfval.f3 << 24);
  34 }
  35
  36 __attribute__ ((noinline, noclone)) uint32_t
  37 partial_read_be32 (union bf_or_uint32 in)
  38 {
  39   return in.bfval.f3 | (in.bfval.f2 << 8)
  40          | (in.bfval.f1 << 16) | (in.bfval.f0 << 24);
  41 }
  42
  43 __attribute__ ((noinline, noclone)) uint32_t
  44 fake_read_le32 (char *x, char *y)
  45 {
  46   unsigned char c0, c1, c2, c3;
  47
  48   c0 = x[0];
  49   c1 = x[1];
  50   *y = 1;
  51   c2 = x[2];
  52   c3 = x[3];
  53   return c0 | c1 << 8 | c2 << 16 | c3 << 24;
  54 }
  55
  56 __attribute__ ((noinline, noclone)) uint32_t
  57 fake_read_be32 (char *x, char *y)
  58 {
  59   unsigned char c0, c1, c2, c3;
  60
  61   c0 = x[0];
  62   c1 = x[1];
  63   *y = 1;
  64   c2 = x[2];
  65   c3 = x[3];
  66   return c3 | c2 << 8 | c1 << 16 | c0 << 24;
  67 }
  68
  69 __attribute__ ((noinline, noclone)) uint32_t
  70 incorrect_read_le32 (char *x, char *y)
  71 {
  72   unsigned char c0, c1, c2, c3;
  73
  74   c0 = x[0];
  75   c1 = x[1];
  76   c2 = x[2];
  77   c3 = x[3];
  78   *y = 1;
  79   return c0 | c1 << 8 | c2 << 16 | c3 << 24;
  80 }
  81
  82 __attribute__ ((noinline, noclone)) uint32_t
  83 incorrect_read_be32 (char *x, char *y)
  84 {
  85   unsigned char c0, c1, c2, c3;
  86
  87   c0 = x[0];
  88   c1 = x[1];
  89   c2 = x[2];
  90   c3 = x[3];
  91   *y = 1;
  92   return c3 | c2 << 8 | c1 << 16 | c0 << 24;
  93 }
  94
  95 int
  96 main ()
  97 {
  98   union bf_or_uint32 bfin;
  99   uint32_t out;
 100   char cin[] = { 0x83, 0x85, 0x87, 0x89 };
 101
 102   if (sizeof (uint32_t) * __CHAR_BIT__ != 32)
 103     return 0;
 104   bfin.inval = (struct ok) { 0x83, 0x85, 0x87, 0x89 };
 105   out = partial_read_le32 (bfin);
 106   /* Test what bswap would do if its check are not strict enough instead of
 107      what is the expected result as there is too many possible results with
 108      bitfields.  */
 109   if (out == 0x89878583)
 110     __builtin_abort ();
 111   bfin.inval = (struct ok) { 0x83, 0x85, 0x87, 0x89 };
 112   out = partial_read_be32 (bfin);
 113   /* Test what bswap would do if its check are not strict enough instead of
 114      what is the expected result as there is too many possible results with
 115      bitfields.  */
 116   if (out == 0x83858789)
 117     __builtin_abort ();
 118   out = fake_read_le32 (cin, &cin[2]);
 119   if (out != 0x89018583)
 120     __builtin_abort ();
 121   cin[2] = 0x87;
 122   out = fake_read_be32 (cin, &cin[2]);
 123   if (out != 0x83850189)
 124     __builtin_abort ();
 125   cin[2] = 0x87;
 126   out = incorrect_read_le32 (cin, &cin[2]);
 127   if (out != 0x89878583)
 128     __builtin_abort ();
 129   cin[2] = 0x87;
 130   out = incorrect_read_be32 (cin, &cin[2]);
 131   if (out != 0x83858789)
 132     __builtin_abort ();
 133   return 0;
 134 }