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Re: RFC/RFA: patch for PR 22156: improve SRA for bit-fields
> > In the testcase, the structure contains exactly 2 fields, which are both
> > words. How does this relate to what you're saying?
>
> Two SImode fields that are laid out in such a way that they can be
> accessed with a single DImode access. The first patch used to
> consider it profitable to create a single variable for them.
That would have been fine if it didn't immediately need to split it up!
SR.8_6 = BIT_FIELD_REF <VIEW_CONVERT_EXPR<struct
gnat__strings__string_access>(D.746), 64, 0>;
lib_opts$P_BOUNDS_7 = BIT_FIELD_REF <SR.8_6, 32, 32>;
lib_opts$P_ARRAY_8 = BIT_FIELD_REF <SR.8_6, 32, 0>;
What's the point in turning 2 COMPONENT_REFs into 3 BIT_FIELD_REFs? Can't we
take that into account to prevent the transformation?
--
Eric Botcazou