On 24/06/14 22:21, Jakub Jelinek wrote:
> 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.

Changed it.

>> +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)

For these flags, value ranges generated are not usable for extension
eliminations. Therefore, without this some of the test cases in
regression fails. For example:

short a;
void
foo (void)
{
  for (a = 0; a >= 0; a++)
    ;
}
-Os  -fno-strict-overflow produces the following range for the index
increment and hence goes into infinite loop.
_10: [1, 32768]
_10 = _4 + 1;

> 
>> +      || (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.

I have changed this. Please see the attached patch.


Thanks,
Kugan

gcc/
2014-06-25  Kugan Vivekanandarajah  <kuganv@linaro.org>

	* 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.
	* expr.h (is_promoted_for_type): New function definition.
	* cfgexpand.c (expand_gimple_stmt_1): Call emit_move_insn if
	SUBREG is promoted with SRP_SIGNED_AND_UNSIGNED.