Merge pull request #1983 from KhronosGroup/fix-1979

HLSL: Add option to emit entry point name 1:1 instead of main().

3 files changed, 44 insertions, 16 deletions

diff --git a/main.cpp b/main.cpp
index b430ec81..81db89ce 100644
--- a/main.cpp
+++ b/main.cpp
@@ -1348,6 +1348,10 @@ static string compile_iteration(const CLIArguments &args, std::vector<uint32_t>
 			build_dummy_sampler = true;
 		}
 
+		// If we're explicitly renaming, we probably want that name to be output.
+		if (!args.entry_point_rename.empty())
+			hlsl_opts.use_entry_point_name = true;
+
 		hlsl_opts.support_nonzero_base_vertex_base_instance = args.hlsl_support_nonzero_base;
 		hlsl_opts.force_storage_buffer_as_uav = args.hlsl_force_storage_buffer_as_uav;
 		hlsl_opts.nonwritable_uav_texture_as_srv = args.hlsl_nonwritable_uav_texture_as_srv;
diff --git a/spirv_hlsl.cpp b/spirv_hlsl.cpp
index c5a37d2c..8c15416c 100644
--- a/spirv_hlsl.cpp
+++ b/spirv_hlsl.cpp
@@ -2404,12 +2404,32 @@ string CompilerHLSL::to_func_call_arg(const SPIRFunction::Parameter &arg, uint32
 	return arg_str;
 }
 
+string CompilerHLSL::get_inner_entry_point_name() const
+{
+	auto &execution = get_entry_point();
+
+	if (hlsl_options.use_entry_point_name)
+	{
+		auto name = join(execution.name, "_inner");
+		ParsedIR::sanitize_underscores(name);
+		return name;
+	}
+
+	if (execution.model == ExecutionModelVertex)
+		return "vert_main";
+	else if (execution.model == ExecutionModelFragment)
+		return "frag_main";
+	else if (execution.model == ExecutionModelGLCompute)
+		return "comp_main";
+	else
+		SPIRV_CROSS_THROW("Unsupported execution model.");
+}
+
 void CompilerHLSL::emit_function_prototype(SPIRFunction &func, const Bitset &return_flags)
 {
 	if (func.self != ir.default_entry_point)
 		add_function_overload(func);
 
-	auto &execution = get_entry_point();
 	// Avoid shadow declarations.
 	local_variable_names = resource_names;
 
@@ -2430,14 +2450,7 @@ void CompilerHLSL::emit_function_prototype(SPIRFunction &func, const Bitset &ret
 
 	if (func.self == ir.default_entry_point)
 	{
-		if (execution.model == ExecutionModelVertex)
-			decl += "vert_main";
-		else if (execution.model == ExecutionModelFragment)
-			decl += "frag_main";
-		else if (execution.model == ExecutionModelGLCompute)
-			decl += "comp_main";
-		else
-			SPIRV_CROSS_THROW("Unsupported execution model.");
+		decl += get_inner_entry_point_name();
 		processing_entry_point = true;
 	}
 	else
@@ -2555,7 +2568,13 @@ void CompilerHLSL::emit_hlsl_entry_point()
 		break;
 	}
 
-	statement(require_output ? "SPIRV_Cross_Output " : "void ", "main(", merge(arguments), ")");
+	const char *entry_point_name;
+	if (hlsl_options.use_entry_point_name)
+		entry_point_name = get_entry_point().name.c_str();
+	else
+		entry_point_name = "main";
+
+	statement(require_output ? "SPIRV_Cross_Output " : "void ", entry_point_name, "(", merge(arguments), ")");
 	begin_scope();
 	bool legacy = hlsl_options.shader_model <= 30;
 
@@ -2728,12 +2747,12 @@ void CompilerHLSL::emit_hlsl_entry_point()
 	});
 
 	// Run the shader.
-	if (execution.model == ExecutionModelVertex)
-		statement("vert_main();");
-	else if (execution.model == ExecutionModelFragment)
-		statement("frag_main();");
-	else if (execution.model == ExecutionModelGLCompute)
-		statement("comp_main();");
+	if (execution.model == ExecutionModelVertex ||
+	    execution.model == ExecutionModelFragment ||
+	    execution.model == ExecutionModelGLCompute)
+	{
+		statement(get_inner_entry_point_name(), "();");
+	}
 	else
 		SPIRV_CROSS_THROW("Unsupported shader stage.");
 
diff --git a/spirv_hlsl.hpp b/spirv_hlsl.hpp
index 23b97f11..f01bcf96 100644
--- a/spirv_hlsl.hpp
+++ b/spirv_hlsl.hpp
@@ -137,6 +137,9 @@ public:
 		// If add_vertex_attribute_remap is used and this feature is used,
 		// the semantic name will be queried once per active location.
 		bool flatten_matrix_vertex_input_semantics = false;
+
+		// Rather than emitting main() for the entry point, use the name in SPIR-V.
+		bool use_entry_point_name = false;
 	};
 
 	explicit CompilerHLSL(std::vector<uint32_t> spirv_)
@@ -374,6 +377,8 @@ private:
 	bool builtin_translates_to_nonarray(spv::BuiltIn builtin) const override;
 
 	std::vector<TypeID> composite_selection_workaround_types;
+
+	std::string get_inner_entry_point_name() const;
 };
 } // namespace SPIRV_CROSS_NAMESPACE