Re: [PATCH 2/2] Enable elimination of zext/sext

[Jakub Jelinek <jakub@redhat.com>]

On Tue, Jun 24, 2014 at 09:53:35PM +1000, Kugan wrote:
> 2014-06-24  Kugan Vivekanandarajah  <kuganv@linaro.org>
> 
> 	* gcc/calls.c (precompute_arguments: Check is_promoted_for_type
> 	and set the promoted mode.
> 	(is_promoted_for_type) : New function.
> 	(expand_expr_real_1) : Check is_promoted_for_type
> 	and set the promoted mode.
> 	* gcc/expr.h (is_promoted_for_type) : New function definition.
> 	* gcc/cfgexpand.c (expand_gimple_stmt_1) : Call emit_move_insn if
> 	SUBREG is promoted with SRP_SIGNED_AND_UNSIGNED.

Similarly to the other patch, no gcc/ prefix in ChangeLog, no space before
:, watch for too long lines, remove useless ()s around conditions.

> +bool
> +is_promoted_for_type (tree ssa, enum machine_mode lhs_mode, bool lhs_uns)
> +{
> +  wide_int type_min, type_max;
> +  wide_int min, max, limit;
> +  unsigned int prec;
> +  tree lhs_type;
> +  bool rhs_uns;
> +
> +  if (flag_wrapv

Why?

> +      || (flag_strict_overflow == false)

Why?  Also, that would be !flag_strict_overflow instead of
(flag_strict_overflow == false)

> +      || (ssa == NULL_TREE)
> +      || (TREE_CODE (ssa) != SSA_NAME)
> +      || !INTEGRAL_TYPE_P (TREE_TYPE (ssa))
> +      || POINTER_TYPE_P (TREE_TYPE (ssa)))

All pointer types are !INTEGRAL_TYPE_P, so the last condition
doesn't make any sense.

	Jakub