bx::sqrt(0.f) will return NaN about bx

[bkaradzic]

Can't repro:

==== Building bx (release) ====
==== Building bx.test (release) ====
math_test.cpp
Linking bx.test
Running...
2023-04-16 20:41:39.397 bx.testRelease[14422:366556] ../../../tests/run_test.cpp(19): Compiler: Clang 14.0.3, CPU: ARM, Architecture: 64-bit, OS: OSX, CRT: Clang C Library, Date: Apr 13 2023, Time: 20:32:22, C++: C++14
Filters: libm
Randomness seeded to: 3232557189
===============================================================================
All tests passed (579889 assertions in 1 test case)

[junjie020]

I want to know, how do you build bx.test target from bx?

Here is what I try to build bx.test taget from bx/makefile, like:

cd bxfolder
make test
.build/osx-x64/bin/bx.testRelease

result:

2023-04-17 16:06:04.935 bx.testRelease[92617:3820883] ../../../tests/run_test.cpp(19): Compiler: Clang 14.0.3, CPU: x86, Architecture: 64-bit, OS: OSX, CRT: Clang C Library, Date: Apr 17 2023, Time: 15:26:31, C++: C++14
Randomness seeded to: 3560497745

bx.testRelease is a Catch2 v3.1.0 host application.
Run with -? for options

-------------------------------------------------------------------------------
isFinite, isInfinite, isNan
-------------------------------------------------------------------------------
../../../tests/math_test.cpp:15
...............................................................................

../../../tests/math_test.cpp:20: FAILED:
  REQUIRE( std::isnan(u.f) == bx::isNan(u.f) )
with expansion:
  false == true

903.920000
-------------------------------------------------------------------------------
Settings
-------------------------------------------------------------------------------
../../../tests/settings_test.cpp:10
...............................................................................

../../../tests/settings_test.cpp:10: FAILED:
  {Unknown expression after the reported line}
due to a fatal error condition:
  SIGSEGV - Segmentation violation signal

===============================================================================
test cases:       35 |       33 passed | 2 failed
assertions: 10154393 | 10154391 passed | 2 failed

It's different from last result which build from my build system. But still have some strange errors.

Could you mind to show me how you build your bx.test target?

My test device is macbook M1 with macOS Ventura 13.2.1

Thanks.

[cloudwu]

I think

bx/include/bx/inline/simd128_neon.inl

Line 655 in 7bbda80

const simd128_neon_t rsqrt = simd_rsqrt(_a);

simd_rsqrt(0) should be NaN here.

[bkaradzic]

Did you try with latest?

[junjie020]

I have try the new code(build from bx/makefile), all test passed.

Beside that, could you mind to define a macro, let the bx lib use the CRT version math methods?

[bkaradzic]

Beside that, could you mind to define a macro, let the bx lib use the CRT version math methods?

Not in official repo, I would suggest you just modify bx for your project to do whatever you need.

[junjie020]

I found it will failed the test with ARM architecture. To reproduce:

cd bxfolder
make osx-arm64-release
./.build/osx-arm64/bin/bx.testRelease

It will log:

2023-04-25 10:19:16.197 bx.testRelease[7498:1704298] ../../../tests/run_test.cpp(19): Compiler: Clang 14.0.3, CPU: ARM, Architecture: 64-bit, OS: OSX, CRT: Clang C Library, Date: Apr 25 2023, Time: 10:18:31, C++: C++14
Randomness seeded to: 2004761687

bx.testRelease is a Catch2 v3.1.0 host application.
Run with -? for options

libm
../../../tests/math_test.cpp:75

../../../tests/math_test.cpp:158: FAILED:
REQUIRE( bx::isNan(bx::sqrtRef(-1.0f) ) )
with expansion:
false

905.025000
test cases: 185 | 184 passed | 1 failed
assertions: 11271229 | 11271228 passed | 1 failed

[bkaradzic]

I found it will failed the test with ARM architecture. To reproduce:

But your original problem is solved? This is sqrtRef failure which is not used by default... I'll fix it, just asking for original issue?

[junjie020]

I try to reproduce my original problem, it can pass the test in release version, but it still failed in debug version.

cd bxfolder
make osx-arm64-debug
/.build/osx-arm64/bin/bx.testDebug

the log:

2023-04-25 10:53:00.302 bx.testDebug[9366:1716925] ../../../tests/run_test.cpp(19): Compiler: Clang 14.0.3, CPU: ARM, Architecture: 64-bit, OS: OSX, CRT: Clang C Library, Date: Apr 25 2023, Time: 10:51:01, C++: C++14
Randomness seeded to: 1175618260

bx.testDebug is a Catch2 v3.1.0 host application.
Run with -? for options

libm
../../../tests/math_test.cpp:75

../../../tests/math_test.cpp:115: FAILED:
REQUIRE( bx::isInfinite(bx::rsqrt(0.0f) ) )
with expansion:
false

905.026000
test cases: 185 | 184 passed | 1 failed
assertions: 11263216 | 11263215 passed | 1 failed

And I add this code in one of the test file, and build as debug version:

REQUIRE(bx::sqrt(0.f) == 0);

It still failed.

[bkaradzic]

Try again with latest.