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Re: [PATCH] Check precision rather than machine mode in STRIP_NOPS and STRIP_SIGN_NOPS

2009/6/9 Adam Nemet <>:
> Richard Guenther writes:
>> On Tue, Jun 9, 2009 at 8:23 AM, Eric Botcazou<> wrote:
>> >> Do you mean here conversions that are processed by STRIP_NOPS? ?STRIP_NOPS
>> >> is not used to process all conversions. ?There are things that are
>> >> converted with other operators like FLOAT_EXPR, FIX_TRUNC_EXPR,
>> >> VIEW_CONVERT_EXPR, etc. ?This code solely handles NOP_EXPR, CONVERT_EXPR
>> >> and NON_LVALUE_EXPR.
>> >
>> > Yes, I was thinking of NOP_EXPR.
>> >
>> >> And even if this type of conversion were used for your example, how would
>> >> keeping the check for TYPE_MODE change anything? ?I am assuming that the
>> >> same machine mode and precision is used for an aggregate type regardless of
>> >> its constness.
>> >
>> > I think the precision is not defined for aggregate types. ?And its mode must
>> > definitely be preserved. ?So you should only change STRIP_{SIGN_}NOPS for
>> > types that have a precision.
>> Indeed, you should do the TYPE_PRECISION check only on
>> INTEGRAL_TYPE_P types and keep the mode check on the rest.
> Can't we also check POINTER_TYPE_P and OFFSET_TYPE?

We can, but I don't think we ever have precision differences there.


> Adam

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