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Re: [patch, ia64] Patch for PR target/44583 to fix signed zeros


On 07/29/2010 01:45 PM, Steve Ellcey wrote:
> +(define_constraint "Z"
> +  "1.0 or (0.0 and !flag_signed_zeros)"
> +  (and (match_code "const_double")
> +       (ior (match_test "op == CONST1_RTX (mode)")
> +	    (and (match_test "op == CONST0_RTX (mode)")
> +		 (match_test "!flag_signed_zeros")))))

That can't be right.  The pointer equality there, as in "G",
should mean that we know we really have a positive zero,
which *can* use FP0.

It would seem you're pessimizing every instance of "x = y + 0".

Which operation is it, specifically, that's failing?


r~


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