[SYCL][libdevice] Keep sign bit of result for std::sin(-0)

[jinge90]

For input '-0', __spirv_ocl_sin returns +0 for float and returns -0 for double, MSVC complex math implementation does depend on this, discarding the signbit for sin(-0) will lead to some corner case failures in exp(std::complex) e2e tests. This patch is a workaround for the issue.

[jinge90]

Hi, @KornevNikita
This PR should fix the pre-ci failure for #16639
Could you try it?
Thanks very much.

[KornevNikita]

@jinge90 I've cherry-picked your commit to my PR, waiting for the pre-commit results.
UPD. yep, the test passes now

[KseniyaTikhomirova]

LGTM but libdevice should be reviewed by another team, not SYCL RT

[Naghasan]

_spirv_ocl_sin returns +0 for float and returns -0 for double, although no definition exists in standard for -0 input

There is and it should return -0, the driver has a bug. See https://registry.khronos.org/OpenCL/specs/3.0-unified/html/OpenCL_C.html#edge-case-behavior, and C99 F.9.1.6 states sin(-0) returns -0.

[bader]

libdevice should be reviewed by another team, not SYCL RT

@KseniyaTikhomirova, I disagree with this statement. libdevice code is owned by SYCL RT team for the last 3+ years. If you want to transfer the ownership to another team, please, open a PR changing https://github.com/intel/llvm/blob/sycl/.github/CODEOWNERS. The PR must be approved by both teams SYCL RT and new libdevice code owner team.

[jinge90]

_spirv_ocl_sin returns +0 for float and returns -0 for double, although no definition exists in standard for -0 input

There is and it should return -0, the driver has a bug. See https://registry.khronos.org/OpenCL/specs/3.0-unified/html/OpenCL_C.html#edge-case-behavior, and C99 F.9.1.6 states sin(-0) returns -0.

Hi, @Naghasan
Thanks very much for pointing out this! I will report this to GPU driver developers and before the driver bug is fixed, we will use this workaround to fix complex math's corner case failure.

[Maetveis]

LGTM, thanks!

[jinge90]

Hi, @intel/llvm-gatekeepers
Could you help merge this PR?
Thanks very much.