Re: Fixing the arm/thumb backends

[Richard Henderson <rth at cygnus dot com>]

On Thu, Oct 07, 1999 at 06:37:51PM +0100, Bernd Schmidt wrote:
> My question is, is this a change that is expected to be necessary
> due to the new genrecog?

It's quite possible.  I'm really surprised at the number of 
problems the new code is turning up that were supposed to 
have been detected before.

> @@ -2086,8 +2086,11 @@ arm_rhs_operand (op, mode)
>       rtx op;
>       enum machine_mode mode;
>  {
> -  return (s_register_operand (op, mode)
> -	  || (GET_CODE (op) == CONST_INT && const_ok_for_arm (INTVAL (op))));
> +  if (GET_CODE (op) == CONST_INT)
> +    return const_ok_for_arm (INTVAL (op));
> +  if (GET_MODE (op) != mode)
> +    return FALSE;
> +  return s_register_operand (op, mode);

You shouldn't need to make this change, as s_register_operand
should be checking the mode.  Further, all mode checks should
allow mode==VOIDmode to match, as that is a signal that we don't
care about the mode of the operand.

> @@ -2098,9 +2101,11 @@ arm_rhsm_operand (op, mode)
> @@ -2111,10 +2116,12 @@ arm_add_operand (op, mode)
> @@ -2122,10 +2129,12 @@ arm_not_operand (op, mode)
> @@ -2302,9 +2321,11 @@ index_operand (op, mode)
> @@ -72,9 +72,11 @@ thumb_cmp_operand (op, mode)

Likewise.

> @@ -2199,10 +2208,12 @@ fpu_rhs_operand (op, mode)
>       rtx op;
>       enum machine_mode mode;
>  {
> +  if (GET_CODE (op) == CONST_DOUBLE)
> +    return (const_double_rtx_ok_for_fpu (op));
> +  if (GET_MODE (op) != mode)
> +    return FALSE;
>    if (s_register_operand (op, mode))
>      return TRUE;
> -  else if (GET_CODE (op) == CONST_DOUBLE)
> -    return (const_double_rtx_ok_for_fpu (op));

You probably want to move the CONST_DOUBLE check after the
mode check.  CONST_DOUBLE is VOIDmode for integers, but 
uses the appropriate mode for FP constants.

> @@ -2212,12 +2223,14 @@ fpu_add_operand (op, mode)

Likewise.

> @@ -2246,6 +2259,9 @@ di_operand (op, mode)
>       rtx op;
>       enum machine_mode mode;
>  {
> +  if (GET_MODE (op) != VOIDmode && GET_MODE (op) != mode)
> +    return FALSE;

This is probably correct; it depends on the context.

> @@ -2316,9 +2337,11 @@ const_shift_operand (op, mode)
>       rtx op;
>       enum machine_mode mode;
>  {
> -  return (power_of_two_operand (op, mode)
> -	  || (immediate_operand (op, mode)
> -	      && (INTVAL (op) < 32 && INTVAL (op) > 0)));
> +  if (GET_CODE (op) == CONST_INT)
> +    return INTVAL (op) < 32 && INTVAL (op) > 0;
> +  if (GET_MODE (op) != mode)
> +    return FALSE;
> +  return power_of_two_operand (op, mode);

This isn't right at all -- power_of_two_operand matches CONST_INT too.

>  (define_insn "*call_insn"
>    [(call (mem:SI (match_operand:SI 0 "" "X"))
> -	 (match_operand:SI 1 "" ""))]
> +	 (match_operand 1 "" ""))]
>    "GET_CODE (operands[0]) == SYMBOL_REF"
>    "bl\\t%a0"
>  [(set_attr "length" "4")])

Oh dear -- you were trying to match a const_int here. 
This is a bug in genrecog.  I'll fix it.


r~