[PATCH] D26817: [APFloat] Implement PPCDoubleDouble add and subtract.

[Hal Finkel via llvm-commits]

hfinkel added a comment.

In https://reviews.llvm.org/D26817#600060, @timshen wrote:

> In https://reviews.llvm.org/D26817#600032, @hfinkel wrote:
>
> > Can you please comment on how similar/different this algorithm is from the one in compiler-rt/lib/builtins/ppc/gcc_qadd.c (and other nearby files)?
>
>
> I didn't look at compiler-rt/lib/builtins/ppc/gcc_qadd.c. These algorithms take time to reason about, so currently the only thing I know is that they are different :P. I chose libgcc's version, because it has a paper to refer to.


Okay, can you explain your comment about overflow/underflow. Can't you do it the same way that the libgcc implementations do?


https://reviews.llvm.org/D26817