Implement notion of a "container format" (#213)

The big addition here is that the Slang "bytecode" is no longer treated as just a "code generation target" (`CodeGenTarget`) akin to DX bytecode (DXBC) or SPIR-V, but instead is a `ContainerFormat` that can be used to emit all the results of a compile request (well, currently just the IR-as-BC, but the intention is there).

Getting to this goal involved some prior checkins that eliminated bogus "targets" that weren't really akin to SPIR-V or DXBC: `-target slang-ir-asm` and `-target reflection-json`. Those targets were really in place to support testing, and so they've been made more explicit testing/debug options.

This change eliminates `-target slang-ir` and instead tries to allow the user to specify `-o foo.slang-module` as an output file name, that indicates the intention to output a "container" file that will wrap up all the generated code.

I've also gone ahead and generalized the existing `-target` option so that we are actually building up a *list* of code generation targets. This is largely just a cleanup, since it forces code to be more aware of when it is doing something target-specific vs. target independent. For example, reflection layout information lives on a requested target, and not on the compile request as a whole, and similarly output code is per-target, per-entry-point.

As a cleanup, I eliminated support for per-translation-unit output. This was vestigial code from back when I used to try and do HLSL generation for a whole translation unit instead of per-entry-point (which turned out to be a lot of complexity for little gain), and it was only being used in the `hello` example and the `render-test` test fixture - in both cases fixing it up was easy enough. I've stubbed out the old `spGetTranslationUnitSource` API, but haven't removed it yet.

1 files changed, 6 insertions, 10 deletions

diff --git a/tools/render-test/slang-support.cpp b/tools/render-test/slang-support.cpp
index dbddd9c4f..bf8b7b9c7 100644
--- a/tools/render-test/slang-support.cpp
+++ b/tools/render-test/slang-support.cpp
@@ -38,6 +38,8 @@ struct SlangShaderCompilerWrapper : public ShaderCompiler
 
         int vertexTranslationUnit = 0;
         int fragmentTranslationUnit = 0;
+        char const* vertexEntryPointName = request.vertexShader.name;
+        char const* fragmentEntryPointName = request.fragmentShader.name;
         if( sourceLanguage == SLANG_SOURCE_LANGUAGE_GLSL )
         {
             // GLSL presents unique challenges because, frankly, it got the whole
@@ -48,13 +50,13 @@ struct SlangShaderCompilerWrapper : public ShaderCompiler
 
             vertexTranslationUnit = spAddTranslationUnit(slangRequest, sourceLanguage, nullptr);
             spAddTranslationUnitSourceString(slangRequest, vertexTranslationUnit, request.source.path, request.source.text);
-
             spTranslationUnit_addPreprocessorDefine(slangRequest, vertexTranslationUnit, "__GLSL_VERTEX__", "1");
+            vertexEntryPointName = "main";
 
             fragmentTranslationUnit = spAddTranslationUnit(slangRequest, sourceLanguage, nullptr);
             spAddTranslationUnitSourceString(slangRequest, fragmentTranslationUnit, request.source.path, request.source.text);
-
             spTranslationUnit_addPreprocessorDefine(slangRequest, fragmentTranslationUnit, "__GLSL_FRAGMENT__", "1");
+            fragmentEntryPointName = "main";
         }
         else
         {
@@ -72,8 +74,8 @@ struct SlangShaderCompilerWrapper : public ShaderCompiler
             spSetCompileFlags(slangRequest, SLANG_COMPILE_FLAG_NO_CHECKING);
         }
 
-        int vertexEntryPoint = spAddEntryPoint(slangRequest, vertexTranslationUnit, request.vertexShader.name,   spFindProfile(slangSession, request.vertexShader.profile));
-        int fragmentEntryPoint = spAddEntryPoint(slangRequest, fragmentTranslationUnit, request.fragmentShader.name, spFindProfile(slangSession, request.fragmentShader.profile));
+        int vertexEntryPoint = spAddEntryPoint(slangRequest, vertexTranslationUnit, vertexEntryPointName,   spFindProfile(slangSession, request.vertexShader.profile));
+        int fragmentEntryPoint = spAddEntryPoint(slangRequest, fragmentTranslationUnit, fragmentEntryPointName, spFindProfile(slangSession, request.fragmentShader.profile));
 
         int compileErr = spCompile(slangRequest);
         if(auto diagnostics = spGetDiagnosticOutput(slangRequest))
@@ -90,12 +92,6 @@ struct SlangShaderCompilerWrapper : public ShaderCompiler
 
         ShaderCompileRequest innerRequest = request;
 
-        if( sourceLanguage != SLANG_SOURCE_LANGUAGE_GLSL )
-        {
-            char const* translatedCode = spGetTranslationUnitSource(slangRequest, 0);
-            innerRequest.source.text = translatedCode;
-        }
-
         char const* vertexCode = spGetEntryPointSource(slangRequest, vertexEntryPoint);
         char const* fragmentCode = spGetEntryPointSource(slangRequest, fragmentEntryPoint);