[Chore] (MG_Util/Program): test in/out linkage across stages

MobileGL/MG_Util/ShaderTranspiler/ShaderCompiler.cpp

@@ -196,6 +196,47 @@ namespace MobileGL {
 
                 return allSpirv;
             }
+
+            Result<String> ShaderCompiler::DecompileShader(Vector<unsigned int> spirv) {
+                spvc_context context = nullptr;
+                spvc_parsed_ir ir = nullptr;
+                spvc_compiler compiler_glsl = nullptr;
+                spvc_compiler_options options = nullptr;
+                spvc_resources resources = nullptr;
+                const spvc_reflected_resource *list = nullptr;
+                const char *result = nullptr;
+                size_t count;
+
+                const SpvId *p_spirv = spirv.data();
+                size_t word_count = spirv.size();
+
+                spvc_context_create(&context);
+                spvc_context_parse_spirv(context, p_spirv, word_count, &ir);
+                spvc_context_create_compiler(context, SPVC_BACKEND_GLSL, ir, SPVC_CAPTURE_MODE_TAKE_OWNERSHIP, &compiler_glsl);
+                spvc_compiler_create_shader_resources(compiler_glsl, &resources);
+                spvc_resources_get_resource_list_for_type(resources, SPVC_RESOURCE_TYPE_UNIFORM_BUFFER, &list, &count);
+                spvc_compiler_create_compiler_options(compiler_glsl, &options);
+
+                spvc_compiler_options_set_uint(options, SPVC_COMPILER_OPTION_GLSL_VERSION, 450);
+                spvc_compiler_options_set_bool(options, SPVC_COMPILER_OPTION_GLSL_ES, SPVC_FALSE);
+                spvc_compiler_options_set_bool(options, SPVC_COMPILER_OPTION_GLSL_VULKAN_SEMANTICS, SPVC_TRUE);
+                spvc_compiler_install_compiler_options(compiler_glsl, options);
+                spvc_compiler_compile(compiler_glsl, &result);
+
+                if (!result) {
+                    ResultInfo r;
+                    r.log += "Failed to compile the shader to GLSL: \n";
+                    r.log += spvc_context_get_last_error_string(context);
+                    r.errc = -5;
+                    return std::unexpected(r);
+                }
+
+                std::string glsl = result;
+
+                spvc_context_destroy(context);
+
+                return glsl;
+            }
         }
     }
 }

MobileGL/MG_Util/ShaderTranspiler/ShaderCompiler.h

@@ -12,6 +12,7 @@ namespace ShaderTranspiler {
     public:
         static Result<SharedPtr<glslang::TShader>> CompileShader(const ShaderAttrib& attrib);
         static Result<Vector<Vector<unsigned>>> LinkProgram(const ProgramAttrib& attrib);
+        static Result<String> DecompileShader(Vector<unsigned int> spirv);
     };
 }
 }