-internal-rvo

src/build_settings.cpp

@@ -579,6 +579,8 @@ struct BuildContext {
 	bool internal_ignore_llvm_verification;
 	bool internal_llvm_mem2reg;
 
+	bool   enable_rvo;
+
 	bool   no_threaded_checker;
 
 	bool   show_debug_messages;

src/llvm_backend_stmt.cpp

@@ -1,4 +1,4 @@
-#define LB_ENABLE_RVO true
+#define LB_ENABLE_RVO build_context.enable_rvo
 
 // NOTE(bill): @RVO Check if a call expression returns by sret with a return type matching dst_type.
 // Returns the callee's function type if eligible for copy elision, nullptr otherwise.

src/main.cpp

@@ -412,6 +412,7 @@ enum BuildFlagKind {
 	BuildFlag_InternalWeakMonomorphization,
 	BuildFlag_InternalLLVMVerification,
 	BuildFlag_InternalLLVMMem2Reg,
+	BuildFlag_InternalEnableRVO,
 
 	BuildFlag_Tilde,
 
@@ -644,6 +645,7 @@ gb_internal bool parse_build_flags(Array<String> args) {
 	add_flag(&build_flags, BuildFlag_InternalWeakMonomorphization, str_lit("internal-weak-monomorphization"), BuildFlagParam_None, Command_all);
 	add_flag(&build_flags, BuildFlag_InternalLLVMVerification, str_lit("internal-ignore-llvm-verification"), BuildFlagParam_None, Command_all);
 	add_flag(&build_flags, BuildFlag_InternalLLVMMem2Reg,     str_lit("internal-llvm-mem2reg"), BuildFlagParam_None, Command_all);
+	add_flag(&build_flags, BuildFlag_InternalEnableRVO,       str_lit("internal-enable-rvo"), BuildFlagParam_None, Command_all);
 
 #if ALLOW_TILDE
 	add_flag(&build_flags, BuildFlag_Tilde,                   str_lit("tilde"),                     BuildFlagParam_None,    Command__does_build);
@@ -1639,6 +1641,10 @@ gb_internal bool parse_build_flags(Array<String> args) {
 						case BuildFlag_InternalLLVMMem2Reg:
 							build_context.internal_llvm_mem2reg = true;
 							break;
+						case BuildFlag_InternalEnableRVO:
+							build_context.enable_rvo = true;
+							break;
+
 
 
 						case BuildFlag_Tilde: