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Re: A new patch for floating point conditional mov on PPo


> 
> 
>   In message <199806102153.RAA17221@jwlab.FEITH.COM>you write:
>   > I believe that this is already handled by:
> 
>   > 
>   > #ifdef REGISTER_CONSTRAINTS
>   >         if (! constrain_operands (insn_code_number, 1))
>   >           fatal_insn_not_found (insn);
>   > #endif
>   > 
>   > in final.c (final_scan_insn).
> This checks that the constraints match, not that the predicate
> matches or that the pattern's condition is true.

...

> However, given the complexities of reload the the uncertainty of it's
> exact operation, if we're going to change that code, I would
> recommend that we call abort for the "can't happen case" rather than
> assuming it can't happen and silently generating incorrect code if
> it does happen.

I suggest we leave it alone since it has been that way for a long time.
I can fold those normal test/compare into my fcmov functions so that we
only need to change one place for that. We can do that optimization
after signed int comparison is fixed.

-- 
H.J. Lu (hjl@gnu.org)


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