Adjust hyperbolic trig functions to use ULP rules #342
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Unlike the standard trig functions which may be implemented as natural calculations or as hyperbolic aproximations, the hyperbolic functions are guaranteed to be hyperbolc aproximations and thus have consistent precision characteristics. These can all be guaranteed within 2 ULP, which gives a better match and will resolve the test failures on AMD GPUs. The `cosh.16` test is not updated in this PR because it is already using ULP rules and 2 ULP range specification.
llvm-beanz
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spall
approved these changes
Aug 11, 2025
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Do we want |
hekota
approved these changes
Aug 11, 2025
Yea, we probably need to for any test that covers NaN behavior. I think we need to figure out some issues with DXC and Clang for how we handle math flags to make sure that |
I filed a follow-up issue to this and assigned it to myself: #348 Once we figure out what needs to be done for SPIRV support I'll go through and cleanup the existing tests. |
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Unlike the standard trig functions which may be implemented as natural calculations or as hyperbolic aproximations, the hyperbolic functions are guaranteed to be hyperbolc aproximations and thus have consistent precision characteristics.
These can all be guaranteed within 2 ULP, which gives a better match and will resolve the test failures on AMD GPUs.
The
cosh.16test is not updated in this PR because it is already using ULP rules and 2 ULP range specification.I've captured a spec issue to follow up on the very wide range requirements for
tanhon NVIDIA GPUs:microsoft/hlsl-specs#601
This issue has also been observed by WGSL and is reflected in their spec:
gpuweb/gpuweb#5199
Fixes #326