Fix issues related to MXCSR register

[M-HT]

These are fixes for issues described in #1059.

[mr-c]

Thank you @M-HT ! Can you add some tests to demonstrate the fixes?

[M-HT]

The first two issues are missing definitions so tests don't make sense, because programs using them fail to compile without the fix.
As for the third issue, I don't know how to demonstrate it.

[mr-c]

In the native-aliases CI test, we convert all of the test case source code to not use prefixed version of the intrinsics and we enable SIMDE_ENABLE_NATIVE_ALIASES to ensure that the aliases work

To test the _MM_ROUND_MASK native alias, write a test that uses SIMDE_ENABLE_NATIVE_ALIASES; likewise for _MM_GET_FLUSH_ZERO_MODE via SIMDE_MM_GET_FLUSH_ZERO_MODE.

I'm less concerned about the third case.

[M-HT]

I'm not sure what meaningful test can be written which uses _MM_ROUND_MASK / _MM_GET_FLUSH_ZERO_MODE.
Also native-aliases.sh script only removes simde prefix and not SIMDE prefix, and it ignores macro "constants" like _MM_ROUND_MASK, _MM_SHUFFLE, ...

[M-HT]

How about this test, is it acceptable ?

static int
test_simde_MXCSR (SIMDE_MUNIT_TEST_ARGS) {
  uint32_t original_mxcsr = simde_mm_getcsr();
  uint32_t masked_mxcsr = original_mxcsr & ~(SIMDE_MM_ROUND_MASK | SIMDE_MM_FLUSH_ZERO_MASK);

  simde_mm_setcsr(masked_mxcsr | SIMDE_MM_ROUND_NEAREST | SIMDE_MM_FLUSH_ZERO_OFF);
  uint32_t rm_nearest_off = HEDLEY_STATIC_CAST(uint32_t, SIMDE_MM_GET_ROUNDING_MODE());
  uint32_t fzm_nearest_off = HEDLEY_STATIC_CAST(uint32_t, SIMDE_MM_GET_FLUSH_ZERO_MODE());

  simde_mm_setcsr(masked_mxcsr | SIMDE_MM_ROUND_NEAREST | SIMDE_MM_FLUSH_ZERO_ON);
  uint32_t rm_nearest_on = HEDLEY_STATIC_CAST(uint32_t, SIMDE_MM_GET_ROUNDING_MODE());
  uint32_t fzm_nearest_on = HEDLEY_STATIC_CAST(uint32_t, SIMDE_MM_GET_FLUSH_ZERO_MODE());

  simde_mm_setcsr(masked_mxcsr | SIMDE_MM_ROUND_DOWN | SIMDE_MM_FLUSH_ZERO_OFF);
  uint32_t rm_down_off = HEDLEY_STATIC_CAST(uint32_t, SIMDE_MM_GET_ROUNDING_MODE());
  uint32_t fzm_down_off = HEDLEY_STATIC_CAST(uint32_t, SIMDE_MM_GET_FLUSH_ZERO_MODE());

  simde_mm_setcsr(masked_mxcsr | SIMDE_MM_ROUND_DOWN | SIMDE_MM_FLUSH_ZERO_ON);
  uint32_t rm_down_on = HEDLEY_STATIC_CAST(uint32_t, SIMDE_MM_GET_ROUNDING_MODE());
  uint32_t fzm_down_on = HEDLEY_STATIC_CAST(uint32_t, SIMDE_MM_GET_FLUSH_ZERO_MODE());

  simde_mm_setcsr(masked_mxcsr | SIMDE_MM_ROUND_UP | SIMDE_MM_FLUSH_ZERO_OFF);
  uint32_t rm_up_off = HEDLEY_STATIC_CAST(uint32_t, SIMDE_MM_GET_ROUNDING_MODE());
  uint32_t fzm_up_off = HEDLEY_STATIC_CAST(uint32_t, SIMDE_MM_GET_FLUSH_ZERO_MODE());

  simde_mm_setcsr(masked_mxcsr | SIMDE_MM_ROUND_UP | SIMDE_MM_FLUSH_ZERO_ON);
  uint32_t rm_up_on = HEDLEY_STATIC_CAST(uint32_t, SIMDE_MM_GET_ROUNDING_MODE());
  uint32_t fzm_up_on = HEDLEY_STATIC_CAST(uint32_t, SIMDE_MM_GET_FLUSH_ZERO_MODE());

  simde_mm_setcsr(masked_mxcsr | SIMDE_MM_ROUND_TOWARD_ZERO | SIMDE_MM_FLUSH_ZERO_OFF);
  uint32_t rm_zero_off = HEDLEY_STATIC_CAST(uint32_t, SIMDE_MM_GET_ROUNDING_MODE());
  uint32_t fzm_zero_off = HEDLEY_STATIC_CAST(uint32_t, SIMDE_MM_GET_FLUSH_ZERO_MODE());

  simde_mm_setcsr(masked_mxcsr | SIMDE_MM_ROUND_TOWARD_ZERO | SIMDE_MM_FLUSH_ZERO_ON);
  uint32_t rm_zero_on = HEDLEY_STATIC_CAST(uint32_t, SIMDE_MM_GET_ROUNDING_MODE());
  uint32_t fzm_zero_on = HEDLEY_STATIC_CAST(uint32_t, SIMDE_MM_GET_FLUSH_ZERO_MODE());

  simde_mm_setcsr(original_mxcsr);

  simde_assert_equal_u32(rm_nearest_off, rm_nearest_on);
  simde_assert_equal_u32(rm_down_off, rm_down_on);
  simde_assert_equal_u32(rm_up_off, rm_up_on);
  simde_assert_equal_u32(rm_zero_off, rm_zero_on);

  simde_assert_equal_u32(fzm_nearest_off, fzm_down_off);
  simde_assert_equal_u32(fzm_nearest_off, fzm_up_off);
  simde_assert_equal_u32(fzm_nearest_off, fzm_zero_off);

  simde_assert_equal_u32(fzm_nearest_on, fzm_down_on);
  simde_assert_equal_u32(fzm_nearest_on, fzm_up_on);
  simde_assert_equal_u32(fzm_nearest_on, fzm_zero_on);

  return 0;
}

[mr-c]

Also native-aliases.sh script only removes simde prefix and not SIMDE prefix, and it ignores macro "constants" like _MM_ROUND_MASK, _MM_SHUFFLE, ...

Oh, I didn't see that. It would be good to add those SIMDE_ prefixed to the script, but I can see how that is a bit tricky with the private SIMDE_ constants and other defines..

How about this test, is it acceptable ?

I like them, thanks! Can you add them to this PR?

[M-HT]

I looked at the how to fix the failing tests and noticed following:
In xmmintrin.h (from gcc, clang and visual studio), functions _mm_getcsr and _mm_setcsr use unsigned int datatype and _MM_GET_ROUNDING_MODE, _MM_SET_ROUNDING_MODE, _MM_GET_FLUSH_ZERO_MODE, _MM_SET_FLUSH_ZERO_MODE are either macros using _mm_getcsr and _mm_setcsr or functions using unsigned int datatype.

In simde, functions simde_mm_getcsr, simde_mm_setcsr, SIMDE_MM_GET_FLUSH_ZERO_MODE, SIMDE_MM_SET_FLUSH_ZERO_MODE use uint32_t datatype (which is an understandable change), but functions SIMDE_MM_GET_ROUNDING_MODE and SIMDE_MM_SET_ROUNDING_MODE use unsigned int datatype.

I think functions SIMDE_MM_GET_ROUNDING_MODE and SIMDE_MM_SET_ROUNDING_MODE should also use uint32_t datatype (to be consistent). Then fixing the failing tests would be simple.

[mr-c]

I think functions SIMDE_MM_GET_ROUNDING_MODE and SIMDE_MM_SET_ROUNDING_MODE should also use uint32_t datatype (to be consistent). Then fixing the failing tests would be simple.

Makes sense to me, please implement that; thank you!

[mr-c]

@M-HT Do you have time to file the bug report with emscripten/llvm? The emscripten people are pretty fast at fixing things

Directions: https://emscripten.org/docs/getting_started/bug_reports.html

Error log: https://github.com/simd-everywhere/simde/actions/runs/6172090486/job/16751643532?pr=1060#step:8:1076

[M-HT]

I created this issue: emscripten-core/emscripten#20250