1  /* { dg-do run } */
       2  /* { dg-options "-Os -fsplit-wide-types" } */
       3  
       4  /* This testcase should uncover bugs like
       5     PR46779
       6     PR45291
       7     PR41894
       8  
       9     The inline asm just serves to direct y into the Y register.
      10     Otherwise, it is hard to write a "stable" test case that
      11     also fails with slight variations in source code, middle- resp.
      12     backend.
      13  
      14     The problem is that Y is also the frame-pointer, and
      15     avr.c:avr_hard_regno_mode_ok disallows QI to get in Y-reg.
      16     However, the y.a = 0 generates a
      17         (set (subreg:QI (reg:HI pseudo)) ...)
      18     where pseudo gets allocated to Y.
      19  
      20     Reload fails to generate the right spill.
      21  */
      22  
      23  #include <stdlib.h>
      24  
      25  struct S
      26  {
      27      unsigned char a, b;
      28  } ab = {12, 34};
      29  
      30  void yoo (struct S y)
      31  {
      32      __asm volatile ("ldi %B0, 56" : "+y" (y));
      33      y.a = 0;
      34      __asm volatile ("; y = %0" : "+y" (y));
      35      ab = y;
      36  }
      37  
      38  int main ()
      39  {
      40      yoo (ab);
      41  
      42      if (ab.a != 0)
      43          abort();
      44  
      45      if (ab.b != 56)
      46          abort();
      47  
      48      exit (0);
      49      
      50      return 0;
      51  }