[llvm-dev] [test-suite] making polybench/symm succeed with "-Ofast" and "-ffp-contract=on"

[Sebastian Pop via llvm-dev]

On Fri, Oct 14, 2016 at 6:10 PM, Hal Finkel <hfinkel at anl.gov> wrote:
>> polybench/linear-algebra/kernels/symm, FP_ABSTOLERANCE=1e1
>> polybench/linear-algebra/solvers/gramschmidt, FP_ABSTOLERANCE=1e0
>> What should be a good relative tolerance to set for these two tests?
>
> What's the minimum relative tolerance that you need for them to pass?

Setting FP_ABSTOLERANCE=1e-5, the two tests are passing
when compiled with -Ofast for the following relative tolerance:

polybench/linear-algebra/kernels/symm, FP_TOLERANCE=1e-10
polybench/linear-algebra/solvers/gramschmidt, FP_TOLERANCE=1e5

gramschmidt passes validation against reference output,
symm does not pass validation against reference output:
I have opened a bug for that:
"__attribute__((optnone)) not respected with -ffast-math or -Ofast"
https://llvm.org/bugs/show_bug.cgi?id=30745

Sebastian