1  /* Area:	ffi_call
       2     Purpose:	Check denorm double value.
       3     Limitations:	none.
       4     PR:		PR26483.
       5     Originator:	From the original ffitest.c  */
       6  
       7  /* { dg-do run } */
       8  /* { dg-options "-mieee" { target alpha*-*-* } } */
       9  
      10  #include "ffitest.h"
      11  #include "float.h"
      12  
      13  typedef union
      14  {
      15    double d;
      16    unsigned char c[sizeof (double)];
      17  } value_type;
      18  
      19  #define CANARY 0xba
      20  
      21  static double dblit(double d)
      22  {
      23    return d;
      24  }
      25  
      26  int main (void)
      27  {
      28    ffi_cif cif;
      29    ffi_type *args[MAX_ARGS];
      30    void *values[MAX_ARGS];
      31    double d;
      32    value_type result[2];
      33    unsigned int i;
      34  
      35    args[0] = &ffi_type_double;
      36    values[0] = &d;
      37    
      38    /* Initialize the cif */
      39    CHECK(ffi_prep_cif(&cif, FFI_DEFAULT_ABI, 1,
      40  		     &ffi_type_double, args) == FFI_OK);
      41    
      42    d = DBL_MIN / 2;
      43    
      44    /* Put a canary in the return array.  This is a regression test for
      45       a buffer overrun.  */
      46    memset(result[1].c, CANARY, sizeof (double));
      47  
      48    ffi_call(&cif, FFI_FN(dblit), &result[0].d, values);
      49    
      50    /* The standard delta check doesn't work for denorms.  Since we didn't do
      51       any arithmetic, we should get the original result back, and hence an
      52       exact check should be OK here.  */
      53   
      54    CHECK(result[0].d == dblit(d));
      55  
      56    /* Check the canary.  */
      57    for (i = 0; i < sizeof (double); ++i)
      58      CHECK(result[1].c[i] == CANARY);
      59  
      60    exit(0);
      61  
      62  }