testcase for validate_replace_rtx_1 fix.

Jan Hubicka jh@suse.cz
Mon Oct 9 11:52:00 GMT 2000


Hi
I've managed to create usefull testcase for validate_replace_rtx_1 bug
I sent patch to last week.  It gets gcse to create incorrect REG_EQUAL
note containing (sign_extend:SI (const_int 255)) by forcing chained
simplification of (sign_extend:SI (subreg:QI (reg:SI))) after replacing
the reg by constant.  This simplification is missed.
Hope that the patch will be now easier to review and we may want to install
the testcase.

int b=1;
main()
{
  int a;
  int c;
  a=0xff;
  for (;b;b--)
  {
    c=1;
    asm(""::"r"(c));
    c=(char)a;
  }
  if (c!=-1)
    abort();
  return c;
}


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