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Re: [RFH][libgcc] fp-bit bit ordering (PR 78804)
- From: Bernd Edlinger <bernd dot edlinger at hotmail dot de>
- To: Oleg Endo <oleg dot endo at t-online dot de>
- Cc: "gcc-patches at gcc dot gnu dot org" <gcc-patches at gcc dot gnu dot org>
- Date: Sun, 29 Sep 2019 08:49:04 +0000
- Subject: Re: [RFH][libgcc] fp-bit bit ordering (PR 78804)
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Hi Oleg,
I think both variants should fix the issues for us.
But I cannot tell if the bitfield access generates
more efficient code or identical code than the
original variant when no ms bitfields are used.
That needs closer inspection of the generated
assembler code, a simple bootstrap / regtest will
probably not be sufficient.
But my thought is if the -mms-bitfields option has such
an impact on this structure, then it would be good if there
was a built-in define that can be used to adjust to and/or
diagnose the problem at compile time.
I think that is missing right now, but wouldn't it be nice to have
a define like __MS_BITFIELD_LAYOUT__ ?
Bernd.