Cycles: Pass string by const reference rather than by value

Some of the functions might have been inlined, but others i don't see
how that was possible (don't think virtual functions can be inlined here).

In any case, better be explicitly optimal in the code.

1 files changed, 8 insertions, 8 deletions

diff --git a/intern/cycles/device/opencl/opencl.h b/intern/cycles/device/opencl/opencl.h
index 399fae9b42e..7da690904aa 100644
--- a/intern/cycles/device/opencl/opencl.h
+++ b/intern/cycles/device/opencl/opencl.h
@@ -84,7 +84,7 @@ public:
 	                                   string *error = NULL);
 	static bool device_version_check(cl_device_id device,
 	                                 string *error = NULL);
-	static string get_hardware_id(string platform_name,
+	static string get_hardware_id(const string& platform_name,
 	                              cl_device_id device_id);
 	static void get_usable_devices(vector<OpenCLPlatformDevice> *usable_devices,
 	                               bool force_all = false);
@@ -247,17 +247,17 @@ public:
 	public:
 		OpenCLProgram() : loaded(false), device(NULL) {}
 		OpenCLProgram(OpenCLDeviceBase *device,
-		              string program_name,
-		              string kernel_name,
-		              string kernel_build_options,
+		              const string& program_name,
+		              const string& kernel_name,
+		              const string& kernel_build_options,
 		              bool use_stdout = true);
 		~OpenCLProgram();
 
 		void add_kernel(ustring name);
 		void load();
 
-		bool is_loaded()    { return loaded; }
-		string get_log()    { return log; }
+		bool is_loaded() const { return loaded; }
+		const string& get_log() const { return log; }
 		void report_error();
 
 		cl_kernel operator()();
@@ -271,8 +271,8 @@ public:
 		bool load_binary(const string& clbin, const string *debug_src = NULL);
 		bool save_binary(const string& clbin);
 
-		void add_log(string msg, bool is_debug);
-		void add_error(string msg);
+		void add_log(const string& msg, bool is_debug);
+		void add_error(const string& msg);
 
 		bool loaded;
 		cl_program program;