Use C++ template types in code generation (#1000)

* WIP: Adding support for C/C++ compilation to slang API.

* Removed BackEndType in test harness -> use SlangPassThrough to identify backends
Only require stage for targets that require it.
Detection of all different backends.

* Windows/Unix create temporary filename.

* WIP: Output CPU binaries.

* Added a pass-through c/c++ test.

* Compile C++/C and store in temporary file.

* Read the binary back into memory.

* Set debug info and optimization flags for C/C++.
Make the CPPCompiler debug/optimization levels match slangs.

* Handling of include paths and math precision.

* Dumping c++/c source and exe/shared library.

* Put hex dump into own util.

* End to end pass through c compilation test.

* WIP: Simple execute test working on Linux/Unix.

* Fix typo on linux.

* WIP: To compile slang to cpp shared library. Report backend compiler errors.

* Compiles slang -> cpp and loads as shared library.

* Fix problem on c-cross-compile test because prelude is now included with <> quotes.

* Run slang generated cpp code - using hard coded data.

* Added cpp-execute-simple, and test output.

* Fix warning that broke win32 build.

* Fix compilation problem on osx.

* When C++ output use template types.

* Require C++14 if using partial specialization for matrix/vector types.

* Merge of master + add c-cross-compile.slang.expected

* Remove c-cross-compile.slang.expected

2 files changed, 48 insertions, 23 deletions

diff --git a/source/core/slang-gcc-compiler-util.cpp b/source/core/slang-gcc-compiler-util.cpp
index 69d68e608..0a53bcac8 100644
--- a/source/core/slang-gcc-compiler-util.cpp
+++ b/source/core/slang-gcc-compiler-util.cpp
@@ -369,7 +369,8 @@ static SlangResult _parseGCCFamilyLine(const UnownedStringSlice& line, LineParse
 
     if (options.sourceType == SourceType::CPP)
     {
-        cmdLine.addArg("-std=c++11");
+        // Need C++14 for partial specialization
+        cmdLine.addArg("-std=c++14");
     }
 
     // Use shared libraries
diff --git a/source/slang/slang-emit-cpp.cpp b/source/slang/slang-emit-cpp.cpp
index d039715e3..2ec087eef 100644
--- a/source/slang/slang-emit-cpp.cpp
+++ b/source/slang/slang-emit-cpp.cpp
@@ -209,6 +209,12 @@ CPPSourceEmitter::IntrinsicOp CPPSourceEmitter::getOperationByName(const Unowned
 
 void CPPSourceEmitter::emitTypeDefinition(IRType* inType)
 {
+    if (m_target == CodeGenTarget::CPPSource)
+    {
+        // All types are templates in C++
+        return;
+    }
+
     IRType* type = _cloneType(inType);
     if (m_typeEmittedMap.TryGetValue(type))
     {
@@ -362,17 +368,26 @@ StringSlicePool::Handle CPPSourceEmitter::_calcTypeName(IRType* type)
             auto vecCount = int(GetIntVal(vecType->getElementCount()));
             const IROp elemType = vecType->getElementType()->op;
 
-            StringBuilder builder;
-            builder << "Vec";
-            UnownedStringSlice postFix = _getCTypeVecPostFix(elemType);
-
-            builder << postFix;
-            if (postFix.size() > 1)
+            if (m_target == CodeGenTarget::CPPSource)
             {
-                builder << "_";
+                StringBuilder builder;
+                builder << "Vector<" << getBuiltinTypeName(elemType) << ", " << vecCount << ">";
+                return m_slicePool.add(builder);
+            }
+            else
+            {             
+                StringBuilder builder;
+                builder << "Vec";
+                UnownedStringSlice postFix = _getCTypeVecPostFix(elemType);
+
+                builder << postFix;
+                if (postFix.size() > 1)
+                {
+                    builder << "_";
+                }
+                builder << vecCount;
+                return m_slicePool.add(builder);
             }
-            builder << vecCount;
-            return m_slicePool.add(builder);
         }
         case kIROp_MatrixType:
         {
@@ -382,22 +397,31 @@ StringSlicePool::Handle CPPSourceEmitter::_calcTypeName(IRType* type)
             const auto rowCount = int(GetIntVal(matType->getRowCount()));
             const auto colCount = int(GetIntVal(matType->getColumnCount()));
 
-            // Make sure there is the vector name too
-            _getTypeName(_getVecType(elementType, colCount));
-
-            StringBuilder builder;
-
-            builder << "Mat";
-            const UnownedStringSlice postFix = _getCTypeVecPostFix(_getCType(elementType->op));
-            builder << postFix;
-            if (postFix.size() > 1)
+            if (m_target == CodeGenTarget::CPPSource)
             {
-                builder << "_";
+                StringBuilder builder;
+                builder << "Matrix<" << getBuiltinTypeName(elementType->op) << ", " << rowCount << ", " << colCount << ">";
+                return m_slicePool.add(builder);
             }
-            builder << rowCount;
-            builder << colCount;
+            else
+            {
+                // Make sure there is the vector name too
+                _getTypeName(_getVecType(elementType, colCount));
 
-            return m_slicePool.add(builder);
+                StringBuilder builder;
+
+                builder << "Mat";
+                const UnownedStringSlice postFix = _getCTypeVecPostFix(_getCType(elementType->op));
+                builder << postFix;
+                if (postFix.size() > 1)
+                {
+                    builder << "_";
+                }
+                builder << rowCount;
+                builder << colCount;
+
+                return m_slicePool.add(builder);
+            }
         }
         case kIROp_HLSLRWStructuredBufferType:
         {