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Re: Simplify floating point conversions


On Tue, Nov 05, 2002 at 06:14:00PM +0100, Jan Hubicka wrote:
> Hi,
> this patch makes us to simplify some of the floating point operations to
> narrower mode when conversions are present.  This include
> +,-,/,*,abs,neg,sqrt/sin/cos/exp.
> I believe it is IEEE safe, but some expert would be welcome.

You should have commented this.  It should not take someone 5
minutes to even figure out what's going on here.  To be sure, it's

	(float)sqrtl(x)   ->  sqrtf((float)x)

correct?  Well, clearly this fails for X = 2**(127 * 2), since
X is not representable as a float, but its square root is.  It
would not be hard to identify similar problems with every other
operation on your list except for ABS/NEG.


r~


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