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Re: [PATCH] Use -frounding-math for math testsuite
From: Roland McGrath <roland@hack.frob.com>
Date: Mon, 7 May 2012 16:00:31 -0700 (PDT)
> Since this exact sequence:
>
>> + sethi %hi(_GLOBAL_OFFSET_TABLE_-4), %##reg; \
>> call __sparc_get_pc_thunk.reg; \
>> or %##reg, %lo(_GLOBAL_OFFSET_TABLE_+4), %##reg; \
>
> must appear together for subtle reasons, it seems wise to put it
> into its own macro with a comment saying that it's important that
> it not be broken up (and why)
>
> Conversely, you could just litter the code with some local labels and use
> -(1f-0b) sorts of calculations instead of -4. Then you could schedule the
> instructions however you want without breaking the semantics. The use of
> the labels would also serve as implicit documentation about what the magic
> constant is needed for. Seems better that way to me.
Ok, I'll just abstract it behind a macro with a big comment, thanks.
Trying to schedule these instructions is what got me into trouble in
the first place, so I'll take a pass on the -(1f-0b) stuff for now.