On Thursday 26 May 2005 14:25, Scott Robert Ladd wrote: > Scott Robert Ladd <[EMAIL PROTECTED]> wrote: > >>May I be so bold as to suggest that -funsafe-math-optimizations be > >>reduced in scope to perform exactly what it's name implies: > >>transformations that may slightly alter the meanding of code. Then move > >>the use of hardware intrinsics to a new -fhardware-math switch. > > Richard Guenther wrote: > > I think the other options implied by -ffast-math apart from > > -funsafe-math-optimizations should (and do?) enable the use of > > hardware intrinsics already. It's only that some of the optimzations > > guarded by -funsafe-math-optimizations could be applied in general. > > A good start may be to enumerate the transformations done on a > > Wiki page and list the flags it is guarded with. > > Unless I've missed something obvious, -funsafe-math-optimizations alone > enables most hardware floating-point intrinsics -- on x86_64 and x86, at > least --. For example, consider a simple line of code that takes the > sine of a constant:
I thought the x86 sin/cos intrinsics were unsafe. ie. they don't gave accurate results in all cases. Paul