harec

commit 92bd3f55a9a6e09da69b59bffeb7ef80a74f616c
parent 6264d353ad68d07c0f675be917e3c59b6cbad23d
Author: Drew DeVault <sir@cmpwn.com>
Date:   Tue, 29 Dec 2020 12:14:50 -0500

parse: implement if expressions

Diffstat:
M
include/ast.h
 | 
6
++++++
M
src/gen.c
 | 
2
+-
M
src/parse.c
 | 
36
++++++++++++++++++++++++++++++++++--

3 files changed, 41 insertions(+), 3 deletions(-)
diff --git a/include/ast.h b/include/ast.h
@@ -162,6 +162,11 @@ struct ast_expression_constant {
 	};
 };
 
+struct ast_expression_if {
+	struct ast_expression *cond;
+	struct ast_expression *true_branch, *false_branch;
+};
+
 struct ast_expression_list {
 	struct ast_expression *expr;
 	struct ast_expression_list *next;
@@ -220,6 +225,7 @@ struct ast_expression {
 		struct ast_expression_binding binding;
 		struct ast_expression_call call;
 		struct ast_expression_constant constant;
+		struct ast_expression_if _if;
 		struct ast_expression_list list;
 		struct ast_expression_measure measure;
 		struct ast_expression_return _return;
diff --git a/src/gen.c b/src/gen.c
@@ -446,7 +446,7 @@ gen_expr_call(struct gen_context *ctx,
 		if (type_is_aggregate(carg->value->result)) {
 			alloc_temp(ctx, &arg->value,
 				carg->value->result, "arg.%d");
-			qval_address(&arg->value);
+			qval_deref(&arg->value);
 		} else {
 			gen_temp(ctx, &arg->value,
 				qtype_for_type(ctx, carg->value->result, true),
diff --git a/src/parse.c b/src/parse.c
@@ -330,6 +330,8 @@ parse_primitive_type(struct parser *par)
 }
 
 static struct ast_expression *parse_simple_expression(struct parser *par);
+static struct ast_expression *parse_complex_expression(struct parser *par);
+static struct ast_expression *parse_compound_expression(struct parser *par);
 
 static struct ast_type *
 parse_enum_type(struct parser *par)
@@ -599,8 +601,6 @@ parse_type(struct parser *par)
 	return type;
 }
 
-static struct ast_expression *parse_complex_expression(struct parser *par);
-
 static struct ast_expression *
 parse_access(struct parser *par, struct identifier ident)
 {
@@ -1295,11 +1295,43 @@ parse_simple_expression(struct parser *par)
 }
 
 static struct ast_expression *
+parse_if_expression(struct parser *par)
+{
+	struct ast_expression *exp = xcalloc(1, sizeof(struct ast_expression));
+	exp->type = EXPR_IF;
+
+	struct token tok = {0};
+
+	want(par, T_LPAREN, &tok);
+	exp->_if.cond = parse_simple_expression(par);
+	want(par, T_RPAREN, &tok);
+
+	exp->_if.true_branch = parse_compound_expression(par);
+
+	switch (lex(par->lex, &tok)) {
+	case T_ELSE:
+		if (lex(par->lex, &tok) == T_IF) {
+			exp->_if.false_branch = parse_if_expression(par);
+		} else {
+			unlex(par->lex, &tok);
+			exp->_if.false_branch = parse_compound_expression(par);
+		}
+		break;
+	default:
+		unlex(par->lex, &tok);
+		break;
+	}
+
+	return exp;
+}
+
+static struct ast_expression *
 parse_complex_expression(struct parser *par)
 {
 	struct token tok;
 	switch (lex(par->lex, &tok)) {
 	case T_IF:
+		return parse_if_expression(par);
 	case T_FOR:
 	case T_MATCH:
 	case T_SWITCH: