diff --git a/src/llvm_backend.cpp b/src/llvm_backend.cpp
index 41a56c312..59d5847dd 100644
--- a/src/llvm_backend.cpp
+++ b/src/llvm_backend.cpp
@@ -1,12 +1,6 @@
 #include "llvm_backend.hpp"
 #include "llvm_abi.cpp"
 
-#ifdef USE_NEW_LLVM_ABI_SYSTEM
-#define USE_LLVM_ABI 1
-#else
-#define USE_LLVM_ABI 0
-#endif
-
 gb_global lbAddr lb_global_type_info_data           = {};
 gb_global lbAddr lb_global_type_info_member_types   = {};
 gb_global lbAddr lb_global_type_info_member_names   = {};
@@ -434,11 +428,7 @@ void lb_addr_store(lbProcedure *p, lbAddr addr, lbValue value) {
 	GB_ASSERT(value.value != nullptr);
 	value = lb_emit_conv(p, value, lb_addr_type(addr));
 
-	if (USE_LLVM_ABI) {
-		lb_emit_store(p, addr.addr, value);
-	} else {
-		LLVMBuildStore(p->builder, value.value, addr.addr.value);
-	}
+	lb_emit_store(p, addr.addr, value);
 }
 
 void lb_const_store(lbValue ptr, lbValue value) {
@@ -1280,146 +1270,85 @@ LLVMTypeRef lb_type_internal(lbModule *m, Type *type) {
 		}
 
 	case Type_Proc:
-		{
-			if (USE_LLVM_ABI) {
-				if (m->internal_type_level > 256) { // TODO HACK(bill): is this really enough?
-					return LLVMPointerType(LLVMIntTypeInContext(m->ctx, 8), 0);
-				} else {
-					unsigned param_count = 0;
-					if (type->Proc.calling_convention == ProcCC_Odin) {
-						param_count += 1;
+		if (m->internal_type_level > 256) { // TODO HACK(bill): is this really enough?
+			return LLVMPointerType(LLVMIntTypeInContext(m->ctx, 8), 0);
+		} else {
+			unsigned param_count = 0;
+			if (type->Proc.calling_convention == ProcCC_Odin) {
+				param_count += 1;
+			}
+
+			if (type->Proc.param_count != 0) {
+				GB_ASSERT(type->Proc.params->kind == Type_Tuple);
+				for_array(i, type->Proc.params->Tuple.variables) {
+					Entity *e = type->Proc.params->Tuple.variables[i];
+					if (e->kind != Entity_Variable) {
+						continue;
 					}
-
-					if (type->Proc.param_count != 0) {
-						GB_ASSERT(type->Proc.params->kind == Type_Tuple);
-						for_array(i, type->Proc.params->Tuple.variables) {
-							Entity *e = type->Proc.params->Tuple.variables[i];
-							if (e->kind != Entity_Variable) {
-								continue;
-							}
-							param_count += 1;
-						}
-					}
-					m->internal_type_level += 1;
-					defer (m->internal_type_level -= 1);
-
-					LLVMTypeRef ret = nullptr;
-					LLVMTypeRef *params = gb_alloc_array(heap_allocator(), LLVMTypeRef, param_count);
-					if (type->Proc.result_count != 0) {
-						Type *single_ret = reduce_tuple_to_single_type(type->Proc.results);
-						ret = lb_type(m, single_ret);
-						if (ret != nullptr) {
-							if (is_type_boolean(single_ret) &&
-							    is_calling_convention_none(type->Proc.calling_convention) &&
-							    type_size_of(single_ret) <= 1) {
-								ret = LLVMInt1TypeInContext(m->ctx);
-							}
-						}
-					}
-
-					isize param_index = 0;
-					if (type->Proc.param_count != 0) {
-						GB_ASSERT(type->Proc.params->kind == Type_Tuple);
-						for_array(i, type->Proc.params->Tuple.variables) {
-							Entity *e = type->Proc.params->Tuple.variables[i];
-							if (e->kind != Entity_Variable) {
-								continue;
-							}
-
-							Type *e_type = reduce_tuple_to_single_type(e->type);
-
-							LLVMTypeRef param_type = nullptr;
-							if (is_type_boolean(e_type) &&
-							    type_size_of(e_type) <= 1) {
-								param_type = LLVMInt1TypeInContext(m->ctx);
-							} else {
-								if (is_type_proc(e_type)) {
-									param_type = lb_type(m, t_rawptr);
-								} else {
-									param_type = lb_type(m, e_type);
-								}
-							}
-
-							params[param_index++] = param_type;
-						}
-					}
-					if (param_index < param_count) {
-						params[param_index++] = lb_type(m, t_rawptr);
-						// params[param_index++] = lb_type(m, t_context_ptr);
-					}
-					GB_ASSERT(param_index == param_count);
-
-
-					lbFunctionType *ft = lb_get_abi_info(m->ctx, params, param_count, ret, ret != nullptr, type->Proc.calling_convention);
-					map_set(&m->function_type_map, hash_type(type), ft);
-					LLVMTypeRef new_abi_fn_ptr_type = lb_function_type_to_llvm_ptr(ft, type->Proc.c_vararg);
-					LLVMTypeRef new_abi_fn_type = LLVMGetElementType(new_abi_fn_ptr_type);
-
-					// LLVMTypeRef new_ret = LLVMGetReturnType(new_abi_fn_type);
-					// LLVMTypeRef old_ret = LLVMGetReturnType(old_abi_fn_type);
-					// unsigned new_count = LLVMCountParamTypes(new_abi_fn_type);
-					// unsigned old_count = LLVMCountParamTypes(old_abi_fn_type);
-					// GB_ASSERT_MSG(new_count == old_count, "%u %u, %s %s", new_count, old_count, LLVMPrintTypeToString(new_abi_fn_type), LLVMPrintTypeToString(old_abi_fn_type));
-					return new_abi_fn_ptr_type;
+					param_count += 1;
 				}
-			} else {
-					LLVMTypeRef old_abi_fn_type = nullptr;
+			}
+			m->internal_type_level += 1;
+			defer (m->internal_type_level -= 1);
 
-					set_procedure_abi_types(type);
-					LLVMTypeRef return_type = LLVMVoidTypeInContext(ctx);
-					if (type->Proc.return_by_pointer) {
-						// Void
-					} else if (type->Proc.abi_compat_result_type != nullptr) {
-						return_type = lb_type(m, type->Proc.abi_compat_result_type);
+			LLVMTypeRef ret = nullptr;
+			LLVMTypeRef *params = gb_alloc_array(heap_allocator(), LLVMTypeRef, param_count);
+			if (type->Proc.result_count != 0) {
+				Type *single_ret = reduce_tuple_to_single_type(type->Proc.results);
+				ret = lb_type(m, single_ret);
+				if (ret != nullptr) {
+					if (is_type_boolean(single_ret) &&
+					    is_calling_convention_none(type->Proc.calling_convention) &&
+					    type_size_of(single_ret) <= 1) {
+						ret = LLVMInt1TypeInContext(m->ctx);
+					}
+				}
+			}
+
+			isize param_index = 0;
+			if (type->Proc.param_count != 0) {
+				GB_ASSERT(type->Proc.params->kind == Type_Tuple);
+				for_array(i, type->Proc.params->Tuple.variables) {
+					Entity *e = type->Proc.params->Tuple.variables[i];
+					if (e->kind != Entity_Variable) {
+						continue;
 					}
 
-					isize extra_param_count = 0;
-					if (type->Proc.return_by_pointer) {
-						extra_param_count += 1;
-					}
-					if (type->Proc.calling_convention == ProcCC_Odin) {
-						extra_param_count += 1;
-					}
+					Type *e_type = reduce_tuple_to_single_type(e->type);
 
-					isize param_count = type->Proc.abi_compat_params.count + extra_param_count;
-					auto param_types = array_make<LLVMTypeRef>(temporary_allocator(), 0, param_count);
-
-					if (type->Proc.return_by_pointer) {
-						array_add(&param_types, LLVMPointerType(lb_type(m, type->Proc.abi_compat_result_type), 0));
-					}
-
-					for_array(i, type->Proc.abi_compat_params) {
-						Type *param = type->Proc.abi_compat_params[i];
-						if (param == nullptr) {
-							continue;
-						}
-						if (type->Proc.params->Tuple.variables[i]->flags & EntityFlag_CVarArg) {
-							GB_ASSERT(i+1 == type->Proc.abi_compat_params.count);
-							break;
-						}
-						if (is_type_tuple(param)) {
-							param = base_type(param);
-							for_array(j, param->Tuple.variables) {
-								Entity *v = param->Tuple.variables[j];
-								if (v->kind != Entity_Variable) {
-									// Sanity check
-									continue;
-								}
-								LLVMTypeRef t = lb_type(m, v->type);
-								array_add(&param_types, t);
-							}
+					LLVMTypeRef param_type = nullptr;
+					if (is_type_boolean(e_type) &&
+					    type_size_of(e_type) <= 1) {
+						param_type = LLVMInt1TypeInContext(m->ctx);
+					} else {
+						if (is_type_proc(e_type)) {
+							param_type = lb_type(m, t_rawptr);
 						} else {
-							array_add(&param_types, lb_type(m, param));
+							param_type = lb_type(m, e_type);
 						}
 					}
-					if (type->Proc.calling_convention == ProcCC_Odin) {
-						array_add(&param_types, lb_type(m, t_rawptr));
-						// array_add(&param_types, lb_type(m, t_context_ptr));
-					}
 
-					old_abi_fn_type = LLVMFunctionType(return_type, param_types.data, cast(unsigned)param_types.count, type->Proc.c_vararg);
-					return LLVMPointerType(old_abi_fn_type, 0);
+					params[param_index++] = param_type;
 				}
+			}
+			if (param_index < param_count) {
+				params[param_index++] = lb_type(m, t_rawptr);
+				// params[param_index++] = lb_type(m, t_context_ptr);
+			}
+			GB_ASSERT(param_index == param_count);
+
+
+			lbFunctionType *ft = lb_get_abi_info(m->ctx, params, param_count, ret, ret != nullptr, type->Proc.calling_convention);
+			map_set(&m->function_type_map, hash_type(type), ft);
+			LLVMTypeRef new_abi_fn_ptr_type = lb_function_type_to_llvm_ptr(ft, type->Proc.c_vararg);
+			LLVMTypeRef new_abi_fn_type = LLVMGetElementType(new_abi_fn_ptr_type);
+
+			// LLVMTypeRef new_ret = LLVMGetReturnType(new_abi_fn_type);
+			// LLVMTypeRef old_ret = LLVMGetReturnType(old_abi_fn_type);
+			// unsigned new_count = LLVMCountParamTypes(new_abi_fn_type);
+			// unsigned old_count = LLVMCountParamTypes(old_abi_fn_type);
+			// GB_ASSERT_MSG(new_count == old_count, "%u %u, %s %s", new_count, old_count, LLVMPrintTypeToString(new_abi_fn_type), LLVMPrintTypeToString(old_abi_fn_type));
+			return new_abi_fn_ptr_type;
 		}
 
 		break;
@@ -1467,7 +1396,7 @@ LLVMTypeRef lb_type(lbModule *m, Type *type) {
 	m->internal_type_level += 1;
 	llvm_type = lb_type_internal(m, type);
 	m->internal_type_level -= 1;
-	if (USE_LLVM_ABI && m->internal_type_level == 0) {
+	if (m->internal_type_level == 0) {
 		map_set(&m->types, hash_type(type), llvm_type);
 		if (is_type_named(type)) {
 			map_set(&m->llvm_types, hash_pointer(llvm_type), type);
@@ -2009,6 +1938,20 @@ void lb_add_proc_attribute_at_index(lbProcedure *p, isize index, char const *nam
 
 
 
+void lb_ensure_abi_function_type(lbModule *m, lbProcedure *p) {
+	if (p->abi_function_type != nullptr) {
+		return;
+	}
+	auto hash = hash_type(p->type);
+	lbFunctionType **ft_found = map_get(&m->function_type_map, hash);
+	if (ft_found == nullptr) {
+		LLVMTypeRef llvm_proc_type = lb_type(p->module, p->type);
+		ft_found = map_get(&m->function_type_map, hash);
+	}
+	GB_ASSERT(ft_found != nullptr);
+	p->abi_function_type = *ft_found;
+	GB_ASSERT(p->abi_function_type != nullptr);
+}
 
 lbProcedure *lb_create_procedure(lbModule *m, Entity *entity) {
 	GB_ASSERT(entity != nullptr);
@@ -2070,12 +2013,9 @@ lbProcedure *lb_create_procedure(lbModule *m, Entity *entity) {
 
 	p->value = LLVMAddFunction(m->mod, c_link_name, func_type);
 
-	lbFunctionType **ft_found = map_get(&m->function_type_map, hash_type(p->type));
-	if (USE_LLVM_ABI && ft_found) {
-		lbFunctionType *abi_ft = *ft_found;
-		p->abi_function_type = abi_ft;
-		lb_add_function_type_attributes(p->value, abi_ft, abi_ft->calling_convention);
-	} else {
+	lb_ensure_abi_function_type(m, p);
+	lb_add_function_type_attributes(p->value, p->abi_function_type, p->abi_function_type->calling_convention);
+	if (false) {
 		lbCallingConventionKind cc_kind = lbCallingConvention_C;
 		// TODO(bill): Clean up this logic
 		if (build_context.metrics.os != TargetOs_js)  {
@@ -2124,10 +2064,6 @@ lbProcedure *lb_create_procedure(lbModule *m, Entity *entity) {
 	// NOTE(bill): offset==0 is the return value
 	isize offset = 1;
 	if (pt->Proc.return_by_pointer) {
-		if (!USE_LLVM_ABI) {
-			lb_add_proc_attribute_at_index(p, 1, "sret");
-			lb_add_proc_attribute_at_index(p, 1, "noalias");
-		}
 		offset = 2;
 	}
 
@@ -2160,14 +2096,6 @@ lbProcedure *lb_create_procedure(lbModule *m, Entity *entity) {
 		}
 	}
 
-	if (!USE_LLVM_ABI && pt->Proc.calling_convention == ProcCC_Odin) {
-		lb_add_proc_attribute_at_index(p, offset+parameter_index, "noalias");
-		lb_add_proc_attribute_at_index(p, offset+parameter_index, "nonnull");
-		lb_add_proc_attribute_at_index(p, offset+parameter_index, "nocapture");
-	}
-
-
-
 
 	{ // Debug Information
 		unsigned line = cast(unsigned)entity->token.pos.line;
@@ -2252,34 +2180,6 @@ lbProcedure *lb_create_dummy_procedure(lbModule *m, String link_name, Type *type
 	}
 
 	isize parameter_index = 0;
-	if (!USE_LLVM_ABI && pt->Proc.param_count) {
-		TypeTuple *params = &pt->Proc.params->Tuple;
-		for (isize i = 0; i < pt->Proc.param_count; i++) {
-			Entity *e = params->variables[i];
-			Type *original_type = e->type;
-			Type *abi_type = pt->Proc.abi_compat_params[i];
-			if (e->kind != Entity_Variable) continue;
-
-			if (i+1 == params->variables.count && pt->Proc.c_vararg) {
-				continue;
-			}
-			if (is_type_tuple(abi_type)) {
-				for_array(j, abi_type->Tuple.variables) {
-					Type *tft = abi_type->Tuple.variables[j]->type;
-					if (e->flags&EntityFlag_NoAlias) {
-						lb_add_proc_attribute_at_index(p, offset+parameter_index+j, "noalias");
-					}
-				}
-				parameter_index += abi_type->Tuple.variables.count;
-			} else {
-				if (e->flags&EntityFlag_NoAlias) {
-					lb_add_proc_attribute_at_index(p, offset+parameter_index, "noalias");
-				}
-				parameter_index += 1;
-			}
-		}
-	}
-
 	if (pt->Proc.calling_convention == ProcCC_Odin) {
 		lb_add_proc_attribute_at_index(p, offset+parameter_index, "noalias");
 		lb_add_proc_attribute_at_index(p, offset+parameter_index, "nonnull");
@@ -2504,7 +2404,8 @@ void lb_begin_procedure_body(lbProcedure *p) {
 
 	GB_ASSERT(p->type != nullptr);
 
-	if (p->abi_function_type) {
+	lb_ensure_abi_function_type(p->module, p);
+	{
 		lbFunctionType *ft = p->abi_function_type;
 
 		unsigned param_offset = 0;
@@ -2602,80 +2503,6 @@ void lb_begin_procedure_body(lbProcedure *p) {
 						res = lb_add_local(p, e->type, e);
 					}
 
-					if (e->Variable.param_value.kind != ParameterValue_Invalid) {
-						lbValue c = lb_handle_param_value(p, e->type, e->Variable.param_value, e->token.pos);
-						lb_addr_store(p, res, c);
-					}
-				}
-			}
-		}
-	} else {
-		i32 parameter_index = 0;
-		lbValue return_ptr_value = {};
-		if (p->type->Proc.return_by_pointer) {
-			// NOTE(bill): this must be parameter 0
-			Type *ptr_type = alloc_type_pointer(reduce_tuple_to_single_type(p->type->Proc.results));
-			Entity *e = alloc_entity_param(nullptr, make_token_ident(str_lit("agg.result")), ptr_type, false, false);
-			e->flags |= EntityFlag_Sret | EntityFlag_NoAlias;
-
-			return_ptr_value.value = LLVMGetParam(p->value, 0);
-			return_ptr_value.type = ptr_type;
-			p->return_ptr = lb_addr(return_ptr_value);
-
-			lb_add_entity(p->module, e, return_ptr_value);
-
-			parameter_index += 1;
-		}
-
-		if (p->type->Proc.params != nullptr) {
-			TypeTuple *params = &p->type->Proc.params->Tuple;
-			auto abi_types = p->type->Proc.abi_compat_params;
-
-			for_array(i, params->variables) {
-				Entity *e = params->variables[i];
-				if (e->kind != Entity_Variable) {
-					continue;
-				}
-				Type *abi_type = e->type;
-				if (abi_types.count > 0) {
-					abi_type = abi_types[i];
-				}
-				if (e->token.string != "") {
-					lb_add_param(p, e, nullptr, abi_type, parameter_index);
-				}
-				if (is_type_tuple(abi_type)) {
-					parameter_index += cast(i32)abi_type->Tuple.variables.count;
-				} else {
-					parameter_index += 1;
-				}
-			}
-		}
-
-
-		if (p->type->Proc.has_named_results) {
-			GB_ASSERT(p->type->Proc.result_count > 0);
-			TypeTuple *results = &p->type->Proc.results->Tuple;
-
-			for_array(i, results->variables) {
-				Entity *e = results->variables[i];
-				GB_ASSERT(e->kind == Entity_Variable);
-
-				if (e->token.string != "") {
-					GB_ASSERT(!is_blank_ident(e->token));
-
-					lbAddr res = {};
-					if (p->type->Proc.return_by_pointer) {
-						lbValue ptr = return_ptr_value;
-						if (results->variables.count != 1) {
-							ptr = lb_emit_struct_ep(p, ptr, cast(i32)i);
-						}
-
-						res = lb_addr(ptr);
-						lb_add_entity(p->module, e, ptr);
-					} else {
-						res = lb_add_local(p, e->type, e);
-					}
-
 					if (e->Variable.param_value.kind != ParameterValue_Invalid) {
 						lbValue c = lb_handle_param_value(p, e->type, e->Variable.param_value, e->token.pos);
 						lb_addr_store(p, res, c);
@@ -4469,53 +4296,30 @@ void lb_build_stmt(lbProcedure *p, Ast *node) {
 		}
 
 
-		if (p->abi_function_type) {
-			if (p->abi_function_type->ret.kind == lbArg_Indirect) {
-				if (res.value != nullptr) {
-					LLVMBuildStore(p->builder, res.value, p->return_ptr.addr.value);
-				} else {
-					LLVMBuildStore(p->builder, LLVMConstNull(p->abi_function_type->ret.type), p->return_ptr.addr.value);
-				}
-
-				lb_emit_defer_stmts(p, lbDeferExit_Return, nullptr);
-
-				LLVMBuildRetVoid(p->builder);
+		lb_ensure_abi_function_type(p->module, p);
+		if (p->abi_function_type->ret.kind == lbArg_Indirect) {
+			if (res.value != nullptr) {
+				LLVMBuildStore(p->builder, res.value, p->return_ptr.addr.value);
 			} else {
-				LLVMValueRef ret_val = res.value;
-				ret_val = OdinLLVMBuildTransmute(p, ret_val, p->abi_function_type->ret.type);
-				if (p->abi_function_type->ret.cast_type != nullptr) {
-					ret_val = OdinLLVMBuildTransmute(p, ret_val, p->abi_function_type->ret.cast_type);
-				}
-
-				lb_emit_defer_stmts(p, lbDeferExit_Return, nullptr);
-				LLVMBuildRet(p->builder, ret_val);
+				LLVMBuildStore(p->builder, LLVMConstNull(p->abi_function_type->ret.type), p->return_ptr.addr.value);
 			}
+
+			lb_emit_defer_stmts(p, lbDeferExit_Return, nullptr);
+
+			LLVMBuildRetVoid(p->builder);
 		} else {
-			GB_ASSERT(!USE_LLVM_ABI);
-
-			if (p->type->Proc.return_by_pointer) {
-				if (res.value != nullptr) {
-					lb_addr_store(p, p->return_ptr, res);
-				} else {
-					lb_addr_store(p, p->return_ptr, lb_const_nil(p->module, p->type->Proc.abi_compat_result_type));
-				}
-
-				lb_emit_defer_stmts(p, lbDeferExit_Return, nullptr);
-
-				LLVMBuildRetVoid(p->builder);
-			} else {
-				GB_ASSERT_MSG(res.value != nullptr, "%.*s", LIT(p->name));
-
-				Type *abi_rt = p->type->Proc.abi_compat_result_type;
-				if (!are_types_identical(res.type, abi_rt)) {
-					res = lb_emit_transmute(p, res, abi_rt);
-				}
-				lb_emit_defer_stmts(p, lbDeferExit_Return, nullptr);
-				LLVMBuildRet(p->builder, res.value);
+			LLVMValueRef ret_val = res.value;
+			ret_val = OdinLLVMBuildTransmute(p, ret_val, p->abi_function_type->ret.type);
+			if (p->abi_function_type->ret.cast_type != nullptr) {
+				ret_val = OdinLLVMBuildTransmute(p, ret_val, p->abi_function_type->ret.cast_type);
 			}
+
+			lb_emit_defer_stmts(p, lbDeferExit_Return, nullptr);
+			LLVMBuildRet(p->builder, ret_val);
 		}
 
 
+
 	case_end;
 
 	case_ast_node(is, IfStmt, node);
@@ -7279,8 +7083,7 @@ lbValue lb_emit_call_internal(lbProcedure *p, lbValue value, lbValue return_ptr,
 	LLVMBasicBlockRef curr_block = LLVMGetInsertBlock(p->builder);
 	GB_ASSERT(curr_block != p->decl_block->block);
 
-	if (USE_LLVM_ABI) {
-
+	{
 		LLVMTypeRef ftp = lb_type(p->module, value.type);
 		LLVMTypeRef ft = LLVMGetElementType(ftp);
 		LLVMValueRef fn = value.value;
@@ -7295,13 +7098,6 @@ lbValue lb_emit_call_internal(lbProcedure *p, lbValue value, lbValue return_ptr,
 		res.value = ret;
 		res.type = abi_rt;
 		return res;
-	} else {
-
-		LLVMValueRef ret = LLVMBuildCall2(p->builder, LLVMGetElementType(lb_type(p->module, value.type)), value.value, args, arg_count, "");;
-		lbValue res = {};
-		res.value = ret;
-		res.type = abi_rt;
-		return res;
 	}
 }
 
@@ -7362,7 +7158,7 @@ lbValue lb_emit_call(lbProcedure *p, lbValue value, Array<lbValue> const &args,
 
 	auto processed_args = array_make<lbValue>(permanent_allocator(), 0, args.count);
 
-	if (USE_LLVM_ABI) {
+	{
 		lbFunctionType **ft_found = nullptr;
 		ft_found = map_get(&m->function_type_map, hash_type(pt));
 		if (!ft_found) {
@@ -7455,95 +7251,6 @@ lbValue lb_emit_call(lbProcedure *p, lbValue value, Array<lbValue> const &args,
 			lb_emit_call_internal(p, value, {}, processed_args, nullptr, context_ptr, inlining);
 		}
 
-	} else {
-		for (isize i = 0; i < param_count; i++) {
-			Entity *e = pt->Proc.params->Tuple.variables[i];
-			if (e->kind != Entity_Variable) {
-				// array_add(&processed_args, args[i]);
-				continue;
-			}
-			GB_ASSERT(e->flags & EntityFlag_Param);
-
-			Type *original_type = e->type;
-			Type *new_type = pt->Proc.abi_compat_params[i];
-			Type *arg_type = args[i].type;
-
-			if (are_types_identical(arg_type, new_type)) {
-				// NOTE(bill): Done
-				array_add(&processed_args, args[i]);
-			} else if (!are_types_identical(original_type, new_type)) {
-				if (is_type_pointer(new_type) && !is_type_pointer(original_type)) {
-					Type *av = core_type(type_deref(new_type));
-					if (are_types_identical(av, core_type(original_type))) {
-						if (e->flags&EntityFlag_ImplicitReference) {
-							array_add(&processed_args, lb_address_from_load_or_generate_local(p, args[i]));
-						} else if (!is_type_pointer(arg_type)) {
-							array_add(&processed_args, lb_copy_value_to_ptr(p, args[i], original_type, 16));
-						}
-					} else {
-						array_add(&processed_args, lb_emit_transmute(p, args[i], new_type));
-					}
-				} else if (new_type == t_llvm_bool) {
-					array_add(&processed_args, lb_emit_conv(p, args[i], new_type));
-				} else if (is_type_integer(new_type) || is_type_float(new_type) || is_type_boolean(new_type)) {
-					array_add(&processed_args, lb_emit_transmute(p, args[i], new_type));
-				} else if (is_type_simd_vector(new_type)) {
-					array_add(&processed_args, lb_emit_transmute(p, args[i], new_type));
-				} else if (is_type_tuple(new_type)) {
-					Type *abi_type = pt->Proc.abi_compat_params[i];
-					Type *st = struct_type_from_systemv_distribute_struct_fields(abi_type);
-					lbValue x = {};
-					i64 st_sz = type_size_of(st);
-					i64 arg_sz = type_size_of(args[i].type);
-					if (st_sz == arg_sz) {
-						x = lb_emit_transmute(p, args[i], st);
-					} else {
-						// NOTE(bill): struct{f32, f32, f32} != struct{#simd[2]f32, f32}
-						GB_ASSERT(st_sz > arg_sz);
-						lbAddr xx = lb_add_local_generated(p, st, false);
-						lbValue pp = lb_emit_conv(p, xx.addr, alloc_type_pointer(args[i].type));
-						lb_emit_store(p, pp, args[i]);
-						x = lb_addr_load(p, xx);
-					}
-					for (isize j = 0; j < new_type->Tuple.variables.count; j++) {
-						lbValue xx = lb_emit_struct_ev(p, x, cast(i32)j);
-						array_add(&processed_args, xx);
-					}
-				}
-			} else {
-				lbValue x = lb_emit_conv(p, args[i], new_type);
-				array_add(&processed_args, x);
-			}
-		}
-
-		if (inlining == ProcInlining_none) {
-			inlining = p->inlining;
-		}
-
-
-		Type *abi_rt = reduce_tuple_to_single_type(pt->Proc.abi_compat_result_type);
-		Type *rt = reduce_tuple_to_single_type(results);
-		if (pt->Proc.return_by_pointer) {
-			lbValue return_ptr = {};
-			if (use_return_ptr_hint && p->return_ptr_hint_value.value != nullptr) {
-				if (are_types_identical(type_deref(p->return_ptr_hint_value.type), rt)) {
-					return_ptr = p->return_ptr_hint_value;
-					p->return_ptr_hint_used = true;
-				}
-			}
-			if (return_ptr.value == nullptr) {
-				lbAddr r = lb_add_local_generated(p, rt, true);
-				return_ptr = r.addr;
-			}
-			GB_ASSERT(is_type_pointer(return_ptr.type));
-			lb_emit_call_internal(p, value, return_ptr, processed_args, nullptr, context_ptr, inlining);
-			result = lb_emit_load(p, return_ptr);
-		} else {
-			result = lb_emit_call_internal(p, value, {}, processed_args, abi_rt, context_ptr, inlining);
-			if (abi_rt != rt) {
-				result = lb_emit_transmute(p, result, rt);
-			}
-		}
 	}
 
 	Entity **found = map_get(&p->module->procedure_values, hash_pointer(value.value));
diff --git a/src/main.cpp b/src/main.cpp
index 4ab4df7be..bc45b80af 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -31,7 +31,7 @@ gb_global Timings global_timings = {0};
 
 #if defined(GB_SYSTEM_OSX)
 	#include <llvm/Config/llvm-config.h>
-	#if LLVM_VERSION_MAJOR < 11 
+	#if LLVM_VERSION_MAJOR < 11
 	#error LLVM Version 11+ is required => "brew install llvm@11"
 	#endif
 #endif
@@ -1844,9 +1844,7 @@ void print_show_unused(Checker *c) {
 
 void enforce_platform_settings(void) {
 #if defined(GB_SYSTEM_OSX) && defined(GB_CPU_ARM)
-	#if defined(USE_NEW_LLVM_ABI_SYSTEM)
-		build_context.use_llvm_api = true;
-	#endif
+	build_context.use_llvm_api = true;
 #endif
 }