exposing FSINCOS to Visual C++ using assembly

Main.cpp

#include "SinCos.h"

#include <cmath>
#include <cassert>
#include <limits>

int main()
{
  constexpr double pi = 3.14159265358979323846;
  constexpr double err = std::numeric_limits<double>::epsilon();
  double radians, sine, cosine, delta;

  for (auto i = 0; i != 16; ++i)
  {
    radians = i * pi / 16;
    SinCos(radians, &sine, &cosine);
    delta = std::abs(std::sin(radians) - sine);
    if (delta > err)
      return 1;
    delta = std::abs(std::cos(radians) - cosine);
    if (delta > err)
      return 1;
  }
  return 0;
}

SinCos.asm

.code

PUBLIC SinCos
; void SinCos(double AngleInRadians, double *pSinAns, double *pCosAns);

angle_on_stack$ = 8

SinCos PROC

  movsd QWORD PTR angle_on_stack$[rsp], xmm0 ; argument angle is in xmm0, move it to the stack
  fld QWORD PTR angle_on_stack$[rsp]         ; push angle onto the FPU stack where we can do FLOPs
  fsincos
  fstp QWORD PTR [r8]  ; store/pop cosine output argument 
  fstp QWORD PTR [rdx] ; store/pop sine output argument
  ret 0

SinCos ENDP

END

SinCos.h

#pragma once

extern "C"
{

#if defined(_M_AMD64)

// 64 bit implementation in MASM
// VS2017> enable MASM by right clicking your project in solution explorer then
// Build Dependencies > Build Customizations > MASM
extern void SinCos(double AngleInRadians, double *pSinAns, double *pCosAns);
// Add your assembly file as a source, but exclude it from 32 bit build

#else

// 32 bit implementation in inline assembly
inline void SinCos(double AngleInRadians, double *pSinAns, double *pCosAns)
{
  double SinAns, CosAns;
  __asm {
    fld QWORD PTR[AngleInRadians]
    fsincos
    fstp QWORD PTR[CosAns]
    fstp QWORD PTR[SinAns]
    fwait
  }
  *pSinAns = SinAns;
  *pCosAns = CosAns;
}

#endif

} // extern "C"

SinCosAsm.filters

<?xml version="1.0" encoding="utf-8"?>
<Project ToolsVersion="4.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
  <ItemGroup>
    <Filter Include="Source Files">
      <UniqueIdentifier>{4FC737F1-C7A5-4376-A066-2A32D752A2FF}</UniqueIdentifier>
      <Extensions>cpp;c;cc;cxx;def;odl;idl;hpj;bat;asm;asmx</Extensions>
    </Filter>
    <Filter Include="Header Files">
      <UniqueIdentifier>{93995380-89BD-4b04-88EB-625FBE52EBFB}</UniqueIdentifier>
      <Extensions>h;hh;hpp;hxx;hm;inl;inc;xsd</Extensions>
    </Filter>
    <Filter Include="Resource Files">
      <UniqueIdentifier>{67DA6AB6-F800-4c08-8B7A-83BB121AAD01}</UniqueIdentifier>
      <Extensions>rc;ico;cur;bmp;dlg;rc2;rct;bin;rgs;gif;jpg;jpeg;jpe;resx;tiff;tif;png;wav;mfcribbon-ms</Extensions>
    </Filter>
  </ItemGroup>
  <ItemGroup>
    <ClInclude Include="SinCos.h">
      <Filter>Header Files</Filter>
    </ClInclude>
  </ItemGroup>
  <ItemGroup>
    <ClCompile Include="Main.cpp">
      <Filter>Source Files</Filter>
    </ClCompile>
  </ItemGroup>
  <ItemGroup>
    <MASM Include="SinCos.asm">
      <Filter>Source Files</Filter>
    </MASM>
  </ItemGroup>
</Project>

SinCosAsm.vcxproj

<?xml version="1.0" encoding="utf-8"?>
<Project DefaultTargets="Build" ToolsVersion="15.0" xmlns="http://schemas.microsoft.com/developer/msbuild/2003">
  <ItemGroup Label="ProjectConfigurations">
    <ProjectConfiguration Include="Debug|Win32">
      <Configuration>Debug</Configuration>
      <Platform>Win32</Platform>
    </ProjectConfiguration>
    <ProjectConfiguration Include="Release|Win32">
      <Configuration>Release</Configuration>
      <Platform>Win32</Platform>
    </ProjectConfiguration>
    <ProjectConfiguration Include="Debug|x64">
      <Configuration>Debug</Configuration>
      <Platform>x64</Platform>
    </ProjectConfiguration>
    <ProjectConfiguration Include="Release|x64">
      <Configuration>Release</Configuration>
      <Platform>x64</Platform>
    </ProjectConfiguration>
  </ItemGroup>
  <ItemGroup>
    <ClInclude Include="SinCos.h" />
  </ItemGroup>
  <ItemGroup>
    <ClCompile Include="Main.cpp" />
  </ItemGroup>
  <ItemGroup>
    <MASM Include="SinCos.asm">
      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">true</ExcludedFromBuild>
      <ExcludedFromBuild Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">true</ExcludedFromBuild>
    </MASM>
  </ItemGroup>
  <PropertyGroup Label="Globals">
    <VCProjectVersion>15.0</VCProjectVersion>
    <ProjectGuid>{F390DF0D-F092-46E8-B8A5-608C3C19BDF4}</ProjectGuid>
    <RootNamespace>AsmHackery</RootNamespace>
    <WindowsTargetPlatformVersion>10.0.15063.0</WindowsTargetPlatformVersion>
    <ProjectName>SinCosAsm</ProjectName>
  </PropertyGroup>
  <Import Project="$(VCTargetsPath)\Microsoft.Cpp.Default.props" />
  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'" Label="Configuration">
    <ConfigurationType>Application</ConfigurationType>
    <UseDebugLibraries>true</UseDebugLibraries>
    <PlatformToolset>v141</PlatformToolset>
    <CharacterSet>MultiByte</CharacterSet>
  </PropertyGroup>
  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'" Label="Configuration">
    <ConfigurationType>Application</ConfigurationType>
    <UseDebugLibraries>false</UseDebugLibraries>
    <PlatformToolset>v141</PlatformToolset>
    <WholeProgramOptimization>true</WholeProgramOptimization>
    <CharacterSet>MultiByte</CharacterSet>
  </PropertyGroup>
  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|x64'" Label="Configuration">
    <ConfigurationType>Application</ConfigurationType>
    <UseDebugLibraries>true</UseDebugLibraries>
    <PlatformToolset>v141</PlatformToolset>
    <CharacterSet>MultiByte</CharacterSet>
  </PropertyGroup>
  <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|x64'" Label="Configuration">
    <ConfigurationType>Application</ConfigurationType>
    <UseDebugLibraries>false</UseDebugLibraries>
    <PlatformToolset>v141</PlatformToolset>
    <WholeProgramOptimization>true</WholeProgramOptimization>
    <CharacterSet>MultiByte</CharacterSet>
  </PropertyGroup>
  <Import Project="$(VCTargetsPath)\Microsoft.Cpp.props" />
  <ImportGroup Label="ExtensionSettings">
    <Import Project="$(VCTargetsPath)\BuildCustomizations\masm.props" />
  </ImportGroup>
  <ImportGroup Label="Shared">
  </ImportGroup>
  <ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
  </ImportGroup>
  <ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
  </ImportGroup>
  <ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">
    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
  </ImportGroup>
  <ImportGroup Label="PropertySheets" Condition="'$(Configuration)|$(Platform)'=='Release|x64'">
    <Import Project="$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props" Condition="exists('$(UserRootDir)\Microsoft.Cpp.$(Platform).user.props')" Label="LocalAppDataPlatform" />
  </ImportGroup>
  <PropertyGroup Label="UserMacros" />
  <PropertyGroup />
  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|Win32'">
    <ClCompile>
      <WarningLevel>Level3</WarningLevel>
      <Optimization>Disabled</Optimization>
      <SDLCheck>true</SDLCheck>
    </ClCompile>
  </ItemDefinitionGroup>
  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">
    <ClCompile>
      <WarningLevel>Level3</WarningLevel>
      <Optimization>Disabled</Optimization>
      <SDLCheck>true</SDLCheck>
    </ClCompile>
  </ItemDefinitionGroup>
  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|Win32'">
    <ClCompile>
      <WarningLevel>Level3</WarningLevel>
      <Optimization>MaxSpeed</Optimization>
      <FunctionLevelLinking>true</FunctionLevelLinking>
      <IntrinsicFunctions>true</IntrinsicFunctions>
      <SDLCheck>true</SDLCheck>
    </ClCompile>
    <Link>
      <EnableCOMDATFolding>true</EnableCOMDATFolding>
      <OptimizeReferences>true</OptimizeReferences>
    </Link>
  </ItemDefinitionGroup>
  <ItemDefinitionGroup Condition="'$(Configuration)|$(Platform)'=='Release|x64'">
    <ClCompile>
      <WarningLevel>Level3</WarningLevel>
      <Optimization>MaxSpeed</Optimization>
      <FunctionLevelLinking>true</FunctionLevelLinking>
      <IntrinsicFunctions>true</IntrinsicFunctions>
      <SDLCheck>true</SDLCheck>
    </ClCompile>
    <Link>
      <EnableCOMDATFolding>true</EnableCOMDATFolding>
      <OptimizeReferences>true</OptimizeReferences>
    </Link>
  </ItemDefinitionGroup>
  <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
  <ImportGroup Label="ExtensionTargets">
    <Import Project="$(VCTargetsPath)\BuildCustomizations\masm.targets" />
  </ImportGroup>
</Project>