First step towards constant unions

1 files changed, 19 insertions, 3 deletions

diff --git a/src/llvm_backend_expr.cpp b/src/llvm_backend_expr.cpp
index 80cab9722..0e8562194 100644
--- a/src/llvm_backend_expr.cpp
+++ b/src/llvm_backend_expr.cpp
@@ -3947,6 +3947,20 @@ gb_internal lbValue lb_build_expr(lbProcedure *p, Ast *expr) {
 	return res;
 }
 
+gb_internal Type *lb_build_expr_original_const_type(Ast *expr) {
+	expr = unparen_expr(expr);
+	Type *type = type_of_expr(expr);
+	if (is_type_union(type)) {
+		if (expr->kind == Ast_CallExpr) {
+			if (expr->CallExpr.proc->tav.mode == Addressing_Type) {
+				Type *res = lb_build_expr_original_const_type(expr->CallExpr.args[0]);
+				return res;
+			}
+		}
+	}
+	return type_of_expr(expr);
+}
+
 gb_internal lbValue lb_build_expr_internal(lbProcedure *p, Ast *expr) {
 	lbModule *m = p->module;
 
@@ -3958,9 +3972,11 @@ gb_internal lbValue lb_build_expr_internal(lbProcedure *p, Ast *expr) {
 	GB_ASSERT_MSG(tv.mode != Addressing_Invalid, "invalid expression '%s' (tv.mode = %d, tv.type = %s) @ %s\n Current Proc: %.*s : %s", expr_to_string(expr), tv.mode, type_to_string(tv.type), token_pos_to_string(expr_pos), LIT(p->name), type_to_string(p->type));
 
 
+
 	if (tv.value.kind != ExactValue_Invalid) {
+		Type *original_type = lb_build_expr_original_const_type(expr);
 		// NOTE(bill): Short on constant values
-		return lb_const_value(p->module, type, tv.value, LB_CONST_CONTEXT_DEFAULT_ALLOW_LOCAL);
+		return lb_const_value(p->module, type, tv.value, LB_CONST_CONTEXT_DEFAULT_ALLOW_LOCAL, original_type);
 	} else if (tv.mode == Addressing_Type) {
 		// NOTE(bill, 2023-01-16): is this correct? I hope so at least
 		return lb_typeid(m, tv.type);
@@ -4041,7 +4057,7 @@ gb_internal lbValue lb_build_expr_internal(lbProcedure *p, Ast *expr) {
 		TypeAndValue tav = type_and_value_of_expr(expr);
 		GB_ASSERT(tav.mode == Addressing_Constant);
 
-		return lb_const_value(p->module, type, tv.value);
+		return lb_const_value(p->module, type, tv.value, LB_CONST_CONTEXT_DEFAULT_ALLOW_LOCAL, tv.type);
 	case_end;
 
 	case_ast_node(se, SelectorCallExpr, expr);
@@ -4322,7 +4338,7 @@ gb_internal lbAddr lb_build_addr_from_entity(lbProcedure *p, Entity *e, Ast *exp
 	GB_ASSERT(e != nullptr);
 	if (e->kind == Entity_Constant) {
 		Type *t = default_type(type_of_expr(expr));
-		lbValue v = lb_const_value(p->module, t, e->Constant.value);
+		lbValue v = lb_const_value(p->module, t, e->Constant.value, LB_CONST_CONTEXT_DEFAULT_NO_LOCAL, e->type);
 		if (LLVMIsConstant(v.value)) {
 			lbAddr g = lb_add_global_generated_from_procedure(p, t, v);
 			return g;