DirectXMath Library compiler directives
Compiler directives tune the functionality that the DirectXMath library uses.
| Directive | Description |
|---|---|
| _XM_NO_INTRINSICS_ | When _XM_NO_INTRINSICS_ is defined, DirectXMath operations are implemented without using any platform-specific intrinsics. Instead, DirectXMath uses only standard floating point operations. By default, _XM_NO_INTRINSICS_ is not defined. This directive overrides all other directives. Therefore, we recommend that you check for _XM_NO_INTRINSICS_ before you determine the status of _XM_ARM_NEON_INTRINSICS_ or _XM_SSE_INTRINSICS_. |
| _XM_SSE_INTRINSICS_ | When _XM_SSE_INTRINSICS_ is defined, code is compiled to use supporting SSE and SSE2 on platforms that support these instruction sets. The Windows versions providing SSE intrinsics support both SSE and SSE2. _XM_SSE_INTRINSICS_ has no effect on systems that do not support SSE and SSE2. By default, _XM_SSE_INTRINSICS_ is defined when users compile for a Windows platform. DirectXMath uses the standard compiler defines (_M_IX86 / _M_AMD64) to determine Windows x86 or Windows x64 targets. |
| _XM_ARM_NEON_INTRINSICS_ | This indicates the DirectXMath implementation uses of the ARM-NEON intrinsics. By default, _XM_ARM_NEON_INTRINSICS_ is defined when users compile for a Windows on ARM / ARM64 platform. DirectXMath uses the standard compiler define (_M_ARM, _M_ARM64) to determine this binary target. ARM-NEON intrinsics support is new to DirectXMath and is not supported by XNAMath 2.x. |
| _XM_SSE3_INTRINSICS_ | New for DirectXMath 3.10. When you specify this compiler directive, DirectXMath functions are implemented to make use of SSE3 intrinsics where applicable; otherwise it uses SSE/SSE2. |
| _XM_SSE4_INTRINSICS_ | New for DirectMath 3.09. When you specify this compiler directive, DirectXMath functions are implemented to make use of SSE3 and SSE4.1 intrinsics where applicable; otherwise it uses SSE/SSE2. When you specify this compiler directive, it also implies _XM_SSE3_INTRINSICS_ and _XM_SSE_INTRINSICS_. |
| _XM_AVX_INTRINSICS_ | New for DirectXMath 3.09. Use of /arch:AVX will enable this directive. When you specify this compiler directive, DirectXMath functions are implemented to make use of SSE3, SSE4.1, and AVX 128-bit intrinsics where applicable; otherwise DirectXMath uses SSE/SSE2. When you specify this compiler directive, it also implies _XM_SSE3_INTRINSICS, _XM_SSE4_INTRINSICS_, and _XM_SSE_INTRINSICS_, and includes a small subset of SSE3 instructions. |
| XM_AVX2_INTRINSICS_ | New for DirectXMath 3.11. Use of /arch:AVX2 enables this directive. When you specify this compiler directive, DirectXMath functions make use of AVX2, F16C/CVT16, FMA3, AVX 128-bit, SSE4.1, and SSE3 intrinsics where applicable. When you use _XM_AVX2_INTRINSICS_, it implies _XM_F16C_INTRINSICS_, _XM_FMA3_INTRINSICS_, _XM_AVX_INTRINSICS_, _XM_SSE_INTRINSICS_, _XM_SSE3_INTRINSICS_, and _XM_SSE4_INTRINSICS_. |
| _XM_F16C_INTRINSICS_ | New for DirectXMath 3.09. When you specify this compiler directive, DirectXMath functions are implemented to make use of SSE3, SSE4.1, AVX 128-bit, and F16C/CVT16 intrinsics where applicable; otherwise DirectXMath uses SSE/SSE2. When you use _XM_F16C_INTRINSICS_, it implies _XM_AVX_INTRINSICS_, _XM_SSE_INTRINSICS_, _XM_SSE3_INTRINSICS_, and _XM_SSE4_INTRINSICS_. |
| _XM_FMA3_INTRINSICS_ | New for DirectXMath 3.11. When you specify this compiler directive, DirectXMath functions will make use of SSE3, SSE4.1, AVX 128-bit, and FMA3 intrinsics where applicable; otherwise DirectXMath uses SSE/SSE2. When you use _XM_FMA3_INTRINSICS_, it implies _XM_AVX_INTRINSICS_, _XM_SSE_INTRINSICS_, _XM_SSE3_INTRINSICS_, and _XM_SSE4_INTRINSICS_. |
| _XM_VECTORCALL_ | This enables the use of the __vectorcall calling convention for Windows x86 or Windows x64 targets. It defaults to _XM_VECTORCALL_=1 when the compiler supports this feature. You can manually set it to _XM_VECTORCALL_=0 to always disable it. __vectorcall is not supported for the Windows on ARM / ARM64 platform or Managed C++. |
| _XM_SVML_INTRINSICS_ | New for DirectXMath 3.16. With VS 2019 or later, this enables the library to use the Intel® Short Vector Matrix Library for x86/x64. |
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