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Re: Second Draft "Unsafe fp optimizations" project description.
- To: dewar at gnat dot com, toon at moene dot indiv dot nluug dot nl
- Subject: Re: Second Draft "Unsafe fp optimizations" project description.
- From: dewar at gnat dot com
- Date: Mon, 6 Aug 2001 20:46:19 -0400 (EDT)
- Cc: gcc at gcc dot gnu dot org
<<E.g., if we want to say that optimization -fblah will cause overflow
when the inputs to the (transformed) expression are in the subset X of
all representable floating point numbers, we have to assume a model - my
suggestion is to use the IEEE-754 model.
But this is meaningless, there *is* no "IEEE-754" model for evaluation of
floating-point expressions in high level languages. So this model needs
a lot of filling out. I refer again to Sam Figueroa's PhD thesis which is
all about such models.