[libc-commits] [libc] [llvm] [libc][math][c23] Add atan2f16 function (PR #183531)

[Xinlong Chen via libc-commits]

Xinlong-Chen wrote:

have checked exhaustive test with a tolerance of `0.5 ULP`:

```
[==========] Running 1 test from 1 test suite.
[ RUN      ] LlvmLibcAtan2f16ExhaustiveTest.AllInputs
-- Testing for FE_TONEAREST in x range [0x0, 0xfc00), y range [0x0, 0xfc00) --
100% is in process     
Test PASSED
-- Testing for FE_UPWARD in x range [0x0, 0xfc00), y range [0x0, 0xfc00) --
100% is in process     
Test PASSED
-- Testing for FE_DOWNWARD in x range [0x0, 0xfc00), y range [0x0, 0xfc00) --
100% is in process     
Test PASSED
-- Testing for FE_TOWARDZERO in x range [0x0, 0xfc00), y range [0x0, 0xfc00) --
100% is in process     
Test PASSED
[       OK ] LlvmLibcAtan2f16ExhaustiveTest.AllInputs (54211186 ms)
Ran 1 tests.  PASS: 1  FAIL: 0
```

https://github.com/llvm/llvm-project/pull/183531