Visual Studio compilation working in test harness (#979)

* Work in progress to be able to invoke VS from within code.

* First pass at windows version of refactor of OSProcessSpawner

* Closer to getting VS path lookup working.

* Make OSString assignable/ctor able

* Work out program files directory directly, so don't have to expand %%.

* WIP: Improve handling of process spawning.

* Add support for splitting input by line.

* * Correctly locates visual studio install
* Added functionality to invoke vs via cmd

* Add option to execute the command line.

* Handle in ProcessUtil for windows -> WinHandle.

* Rename files slang-win-visual-studio-util.cpp/.h and slang-process-util.h

* First pass at unix/linux version of ProcessUtil.

* Fix reading Visual Studio path from the registry.

* Get compiling on linux with.

* Fix vcvarsall.bat name

* Use ProcessUtil to execute external code.

* Remove OSProcessSpawner.

* Remove includes for "os.h" where no longer needed.

* Fix tabbing issue in premake5.lua
Remove test code from slang-test-main.cpp

* Fix premake4.lua tabbing issue.

* Small fixes to slang-process-util.h
Init ExecuteResult on Win execute.

* Improve comments.

* Fix bug in StringUtil::calcLines - with oddly terminated source input being able to read past end.
Make slang-generate use StringUtil over it's own impl.

* Fix off by one bug in working out Visual Studio version.

* Fix bug in calculating Visual Studio Version

* Fix compilation on linux with string parameter being passed to messageFormat.

* Remove erroneous use of kOSError codes - use Result.

* First effort to generate standard compiler options.

* Initial efforts in compiling source code in test framework for VisualStudio.

* Testing compiling c code on VisualStudio on Windows.

* Fix warning on linux.

* Fix clang on linux warning (and therefore failing) returning a StringBuilder as String.

* Disable return-std-move on clang.

1 files changed, 121 insertions, 0 deletions

diff --git a/source/core/windows/slang-win-visual-studio-util.cpp b/source/core/windows/slang-win-visual-studio-util.cpp
index edf33110c..5fc56d091 100644
--- a/source/core/windows/slang-win-visual-studio-util.cpp
+++ b/source/core/windows/slang-win-visual-studio-util.cpp
@@ -336,4 +336,125 @@ static SlangResult _find(int versionIndex, WinVisualStudioUtil::VersionPath& out
     }
 }
 
+/* static */void WinVisualStudioUtil::calcArgs(const CPPCompileOptions& options, CommandLine& cmdLine)
+{
+    typedef CPPCompileOptions::OptimizationLevel OptimizationLevel;
+    typedef CPPCompileOptions::TargetType TargetType;
+    typedef CPPCompileOptions::DebugInfoType DebugInfoType;
+
+    // https://docs.microsoft.com/en-us/cpp/build/reference/compiler-options-listed-alphabetically?view=vs-2019
+
+    cmdLine.addArg("/nologo");
+    // Generate complete debugging information
+    cmdLine.addArg("/Zi");
+    // Display full path of source files in diagnostics
+    cmdLine.addArg("/FC");
+
+    switch (options.optimizationLevel)
+    {
+        case OptimizationLevel::Debug:
+        {
+            // No optimization
+            cmdLine.addArg("/Od");
+            
+            cmdLine.addArg("/MDd");
+            break;
+        }
+        case OptimizationLevel::Normal:
+        {
+            cmdLine.addArg("/O2");
+            // Multithreaded DLL
+            cmdLine.addArg("/MD");
+            break;
+        }
+        default: break;
+    }
+
+    // /Fd - followed by name of the pdb file
+    if (options.debugInfoType != DebugInfoType::None)
+    {
+        StringBuilder builder;
+        builder << "/Fd" << options.modulePath << ".pdb";
+        cmdLine.addArg(builder);
+    }
+    
+    switch (options.targetType)
+    {
+        case TargetType::SharedLibrary:
+        {
+            // Create dynamic link library
+            if (options.optimizationLevel == OptimizationLevel::Debug)
+            {
+                cmdLine.addArg("/LDd");
+            }
+            else
+            {
+                cmdLine.addArg("/LD");
+            }
+
+            StringBuilder builder;
+            builder << "/Fe" << options.modulePath << ".dll";
+            cmdLine.addArg(builder);
+            break;
+        }
+        case TargetType::Executable:
+        {
+            StringBuilder builder;
+            builder << "/Fe" << options.modulePath << ".exe";
+            cmdLine.addArg(builder);
+            break;
+        }
+        default: break;
+    }
+
+    // Object file specify it's location - needed if we are out
+    {
+        StringBuilder builder;
+        builder << "/Fo" << options.modulePath << ".obj";
+        cmdLine.addArg(builder);
+    }
+
+    // Add defines
+    for (const auto& define : options.defines)
+    {
+        StringBuilder builder;
+        builder << define.nameWithSig;
+        if (define.value.getLength())
+        {
+            builder << "=" << define.value;
+        }
+
+        cmdLine.addArg(builder);
+    }
+
+    // Add includes
+    for (const auto& include : options.includePaths)
+    {
+        cmdLine.addArg("/I");
+        cmdLine.addArg(include);
+    }
+
+    
+    // https://docs.microsoft.com/en-us/cpp/build/reference/eh-exception-handling-model?view=vs-2019
+    // /Eha - Specifies the model of exception handling. (a, s, c, r are options)
+
+    // Files to compile
+    for (const auto& sourceFile : options.sourceFiles)
+    {
+        cmdLine.addArg(sourceFile);
+    }
+
+    // Link options (parameters past /link go to linker)
+    cmdLine.addArg("/link");
+
+    for (const auto& libPath : options.libraryPaths)
+    {
+        // Note that any escaping of the path is handled in the ProcessUtil::
+        StringBuilder builder;
+        builder << "/LIBPATH:" << libPath;
+
+        cmdLine.addArg(builder);
+    }
+}
+
 } // namespace Slang