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Re: get_condition and conditional move



  In message <m0ymAuj-00026AC@ocean.lucon.org>you write:
  > > No, read again.  This test applies only when flag_fast_math is zero.
  > > Reversing a inequality comparison does not work correctly when handling NaNs.
Generally this is true.  However, it is safe to reverse EQ and NE
comparisons, even for ieee floating point.

If some operand is a NaN, then  EQ always evaluates to false and
NE will always evaluate to true.

See "can_reverse_comparison_p" in jump.c

jeff


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