Make lb_create_enum_attribute ignore certain attributes (they are not properly supported by the actual LLVM C API)

src/llvm_abi.cpp

@@ -443,9 +443,7 @@ namespace lbAbi386 {
 			case 4: return lb_arg_type_direct(return_type, LLVMIntTypeInContext(c, 32), nullptr, nullptr);
 			case 8: return lb_arg_type_direct(return_type, LLVMIntTypeInContext(c, 64), nullptr, nullptr);
 			}
-			LLVMAttributeRef attr = nullptr;
-			// TODO(bill): sret doesn't work correct for LLVM C API
-			// attr = lb_create_enum_attribute(c, "sret", true);
+			LLVMAttributeRef attr = lb_create_enum_attribute(c, "sret", true);
 			return lb_arg_type_indirect(return_type, attr);
 		}
 		return non_struct(c, return_type, true);
@@ -604,8 +602,7 @@ namespace lbAbiAmd64SysV {
 			if (attribute_kind == Amd64TypeAttribute_ByVal) {
 				attribute = lb_create_enum_attribute(c, "byval", true);
 			} else if (attribute_kind == Amd64TypeAttribute_StructRect) {
-				// TODO(bill): sret doesn't work correct for LLVM C API
-				// attribute = lb_create_enum_attribute(c, "sret", true);
+				attribute = lb_create_enum_attribute(c, "sret", true);
 			}
 			return lb_arg_type_indirect(type, attribute);
 		} else {
@@ -904,9 +901,7 @@ namespace lbAbiAmd64SysV {
 			case 4: return lb_arg_type_direct(return_type, LLVMIntTypeInContext(c, 32), nullptr, nullptr);
 			case 8: return lb_arg_type_direct(return_type, LLVMIntTypeInContext(c, 64), nullptr, nullptr);
 			}
-			LLVMAttributeRef attr = nullptr;
-			// TODO(bill): sret doesn't work correct for LLVM C API
-			// attr = lb_create_enum_attribute(c, "sret", true);
+			LLVMAttributeRef attr = lb_create_enum_attribute(c, "sret", true);
 			return lb_arg_type_indirect(return_type, attr);
 		} else if (build_context.metrics.os == TargetOs_windows && lb_is_type_kind(return_type, LLVMIntegerTypeKind) && lb_sizeof(return_type) == 16) {
 			return lb_arg_type_direct(return_type, LLVMIntTypeInContext(c, 128), nullptr, nullptr);
@@ -1055,9 +1050,7 @@ namespace lbAbiArm64 {
 				}
 				return lb_arg_type_direct(type, cast_type, nullptr, nullptr);
 			} else {
-				LLVMAttributeRef attr = nullptr;
-				// TODO(bill): sret doesn't work correct for LLVM C API
-				// attr = lb_create_enum_attribute(c, "sret", true);
+				LLVMAttributeRef attr = lb_create_enum_attribute(c, "sret", true);
 				return lb_arg_type_indirect(type, attr);
 			}
 		}

src/llvm_backend.cpp

@@ -1977,7 +1977,22 @@ lbValue lb_emit_string(lbProcedure *p, lbValue str_elem, lbValue str_len) {
 }
 
 LLVMAttributeRef lb_create_enum_attribute(LLVMContextRef ctx, char const *name, u64 value) {
-	unsigned kind = LLVMGetEnumAttributeKindForName(name, gb_strlen(name));
+	String s = make_string_c(name);
+
+	// NOTE(2021-02-25, bill); All this attributes require a type associated with them
+	// and the current LLVM C API does not expose this functionality yet.
+	// It is better to ignore the attributes for the time being
+	if (s == "byval") {
+		return nullptr;
+	} else if (s == "byref") {
+		return nullptr;
+	} else if (s == "preallocated") {
+		return nullptr;
+	} else if (s == "sret") {
+		return nullptr;
+	}
+
+	unsigned kind = LLVMGetEnumAttributeKindForName(name, s.len);
 	GB_ASSERT_MSG(kind != 0, "unknown attribute: %s", name);
 	return LLVMCreateEnumAttribute(ctx, kind, value);
 }