Long Vector Execution tests preliminary work to merge a minor refactor. (microsoft#7532)

This resolves issue microsoft#7531. This is a preliminary step to merging in some
of the Long Vector Execution tests currently sitting in the
staging-sm6.9 branch. There are no functional changes here, but given
that this is a refactor I do not want to add the [NFC] tag to the PR
title.

- Moves functions used by existing exec tests and incoming long vector
tests to a common HlslExecTestUtils.h.
- Updates naming to adhere to LLVM coding standards for newly created
files (even though the functions aren't new)
- Move a few other shared functions to files that make more sense than
ExecutionTest.cpp.
- TableParameterHandler class moved to its own header/cpp files. No
naming updates as nothing else was touched. Can update in a subsequent
PR if it is preferred.
- Add the LLVM coding guidelines preferred include guard to
HlslTestUtils.h to mitigate redefinition issues exposed by this
refactor.
- Updated the D3D shader model 'redefines' in ExecutionTest.cpp as they
were also factored out into a common header. constexpr required because
they are enum values.
- BigObj added to the cmake file as I was hitting issues locally for
this.

Author: alsepkow

include/dxc/Test/HlslTestUtils.h

@@ -10,6 +10,8 @@
 ///////////////////////////////////////////////////////////////////////////////
 
 // *** THIS FILE CANNOT TAKE ANY LLVM DEPENDENCIES  *** //
+#ifndef HLSLTESTUTILS_H
+#define HLSLTESTUTILS_H
 
 #include <algorithm>
 #include <atomic>
@@ -735,3 +737,5 @@ inline UINT GetByteSizeForFormat(DXGI_FORMAT value) {
   }
 }
 #endif
+
+#endif // HLSLTESTUTILS_H

tools/clang/unittests/HLSLExec/CMakeLists.txt

@@ -3,9 +3,12 @@
 find_package(TAEF REQUIRED)
 find_package(D3D12 REQUIRED) # Used for ExecutionTest.cpp.
 
+set(CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} /bigobj")
+
 add_clang_library(ExecHLSLTests SHARED
   ExecutionTest.cpp
   ShaderOpTest.cpp
+  TableParameterHandler.cpp
   ExecHLSLTests.rc
   )