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Re: [PATCH] Optimize abs(x) < 0.0
Richard Henderson <rth@redhat.com> writes:
| > 2) Even in the case where fabs(x)
| > may not cause a trap by itself, the expression
| >
| > fabs(x) < 0.0
| >
| > may because of the comparaison (SPARC V9 for example has mode to
| > trigger exception when comparing a signaling NaN against something).
|
| We don't preserve signals anywere else in gcc (e.g. eliminated
| because the result is dead). I don't see why we should start now.
Then, what does GCC return for fabs(x) when x is a signaling NaN?
-- Gaby