Add clean_func_name() to support overrides to function names.

spirv_glsl.cpp

@@ -2710,6 +2710,15 @@ string CompilerGLSL::to_function_args(uint32_t img, const SPIRType &, bool, bool
 	return farg_str;
 }
 
+// Some languages may have additional standard library functions whose names conflict
+// with a function defined in the body of the shader. Subclasses can override to rename
+// the function name defined in the shader to avoid conflict with the language standard
+// functions (eg. MSL includes saturate()).
+string CompilerGLSL::clean_func_name(string func_name)
+{
+    return func_name;
+}
+
 void CompilerGLSL::emit_glsl_op(uint32_t result_type, uint32_t id, uint32_t eop, const uint32_t *args, uint32_t)
 {
 	GLSLstd450 op = static_cast<GLSLstd450>(eop);
@@ -3638,7 +3647,7 @@ void CompilerGLSL::emit_instruction(const Instruction &instruction)
 
 		string funexpr;
 		vector<string> arglist;
-		funexpr += to_name(func) + "(";
+		funexpr += clean_func_name(to_name(func)) + "(";
 		for (uint32_t i = 0; i < length; i++)
 		{
 			// Do not pass in separate images or samplers if we're remapping
@@ -5359,11 +5368,11 @@ void CompilerGLSL::emit_function_prototype(SPIRFunction &func, uint64_t return_f
 
 	if (func.self == entry_point)
 	{
-		decl += "main";
+		decl += clean_func_name("main");
 		processing_entry_point = true;
 	}
 	else
-		decl += to_name(func.self);
+		decl += clean_func_name(to_name(func.self));
 
 	decl += "(";
 	vector<string> arglist;

spirv_glsl.hpp

@@ -168,6 +168,7 @@ protected:
 	                                     uint32_t grad_x, uint32_t grad_y, uint32_t lod, uint32_t coffset,
 	                                     uint32_t offset, uint32_t bias, uint32_t comp, uint32_t sample,
 	                                     bool *p_forward);
+    virtual std::string clean_func_name(std::string func_name);
 
 	std::unique_ptr<std::ostringstream> buffer;
 

spirv_msl.cpp

@@ -27,6 +27,15 @@ CompilerMSL::CompilerMSL(vector<uint32_t> spirv_)
     : CompilerGLSL(move(spirv_))
 {
 	options.vertex.fixup_clipspace = false;
+
+    populate_func_name_overrides();
+}
+
+// Populate the collection of function names that need to be overridden
+void CompilerMSL::populate_func_name_overrides()
+{
+    func_name_overrides["main"] = "main0";
+    func_name_overrides["saturate"] = "saturate0";
 }
 
 string CompilerMSL::compile(MSLConfiguration &msl_cfg, vector<MSLVertexAttr> *p_vtx_attrs,
@@ -1203,8 +1212,8 @@ string CompilerMSL::func_type_decl(SPIRType &type)
 // Ensures the function name is not "main", which is illegal in MSL
 string CompilerMSL::clean_func_name(string func_name)
 {
-	static std::string _clean_msl_main_func_name = "mmain";
+    auto iter = func_name_overrides.find(func_name);
-	return (func_name == "main") ? _clean_msl_main_func_name : func_name;
+    return (iter != func_name_overrides.end()) ? iter->second : func_name;
 }
 
 // Returns a string containing a comma-delimited list of args for the entry point function

spirv_msl.hpp

@@ -115,6 +115,7 @@ protected:
 	                             uint32_t coord, uint32_t coord_components, uint32_t dref, uint32_t grad_x,
 	                             uint32_t grad_y, uint32_t lod, uint32_t coffset, uint32_t offset, uint32_t bias,
 	                             uint32_t comp, uint32_t sample, bool *p_forward) override;
+    std::string clean_func_name(std::string func_name) override;
 
 	void register_custom_functions();
 	void emit_custom_functions();
@@ -129,9 +130,9 @@ protected:
 	void emit_interface_block(uint32_t ib_var_id);
 	void emit_function_prototype(SPIRFunction &func, bool is_decl);
 	void emit_function_declarations();
+    void populate_func_name_overrides();
 
 	std::string func_type_decl(SPIRType &type);
-	std::string clean_func_name(std::string func_name);
 	std::string entry_point_args(bool append_comma);
 	std::string get_entry_point_name();
 	std::string to_qualified_member_name(const SPIRType &type, uint32_t index);
@@ -148,6 +149,7 @@ protected:
 	std::string to_component_argument(uint32_t id);
 
 	MSLConfiguration msl_config;
+    std::unordered_map<std::string,std::string> func_name_overrides;
 	std::set<uint32_t> custom_function_ops;
 	std::unordered_map<uint32_t, MSLVertexAttr *> vtx_attrs_by_location;
 	std::vector<MSLResourceBinding *> resource_bindings;