search for: fusedmultiplyadd

Hi All, APFloat::fusedMultiplyAdd currently computes the wrong signed zero when small negative results are truncated back to zero in standard precision. The following snippet handles the signedness in fusedMultiplyAdd: /* If two numbers add (exactly) to zero, IEEE 754 decrees it is a positive zero unless rounding to minus infin...

...mits, where this email should have gone in the first place. :) Cheers, Lang. On Thu, Jan 1, 2015 at 10:56 PM, Mehdi Amini <mehdi.amini at apple.com> wrote: > Hi Lang, > > On Jan 1, 2015, at 5:57 PM, Lang Hames <lhames at gmail.com> wrote: > > Hi All, > > APFloat::fusedMultiplyAdd currently computes the wrong signed zero when > small negative results are truncated back to zero in standard precision. > The following snippet handles the signedness in fusedMultiplyAdd: > > /* If two numbers add (exactly) to zero, IEEE 754 decrees it is a > positive zero unless...

Hi Sanjay, You are right. I tried XL and gcc 4.8.2 for PPC and I also got multiply-and-add operations. I supported my statement on what I read in the gcc man page. -ffast-math is used in clang to set fp-contract to fast (default is standard) and in gcc it activates (among others) the flag -funsafe-math-optimizations whose description includes: "Allow optimizations for floating-point

This patch supplies software IEEE floating point support. The comment from the patch reproduced below says all there is to say. This patch contains the prior "cleanup" patch; please don't apply that one. Please let me know of any bugs. It is tested reasonably well, but until I put together random tests it's hard to have 100% confidence. Neil. /* A self-contained host- and