harec

commit 56853be54d30eded69604d2d6efd3cefd6e1e805
parent dcce8b33f57727f8b29dce99a5bf0785b20cb99e
Author: Drew DeVault <sir@cmpwn.com>
Date:   Wed, 23 Dec 2020 13:24:50 -0500

check: initial support for assignments

Diffstat:
M
include/ast.h
 | 
2
+-
M
include/expr.h
 | 
6
++++++
M
src/check.c
 | 
27
++++++++++++++++++++++++++-
M
src/parse.c
 | 
8
++++----

4 files changed, 37 insertions(+), 6 deletions(-)
diff --git a/include/ast.h b/include/ast.h
@@ -91,7 +91,7 @@ struct ast_expression_access {
 };
 
 struct ast_expression_assign {
-	struct ast_expression *lvalue, *rvalue;
+	struct ast_expression *object, *value;
 	bool indirect;
 };
 
diff --git a/include/expr.h b/include/expr.h
@@ -44,6 +44,11 @@ struct expression_access {
 	// TODO: Details for index, field selection
 };
 
+struct expression_assign {
+	struct expression *object, *value;
+	bool indirect;
+};
+
 enum binarithm_operator {
 	BIN_BAND,
 	BIN_BNOT,
@@ -112,6 +117,7 @@ struct expression {
 	bool terminates;
 	union {
 		struct expression_access access;
+		struct expression_assign assign;
 		struct expression_binarithm binarithm;
 		struct expression_binding binding;
 		union expression_constant constant;
diff --git a/src/check.c b/src/check.c
@@ -53,6 +53,29 @@ check_expr_access(struct context *ctx,
 }
 
 static void
+check_expr_assign(struct context *ctx,
+	const struct ast_expression *aexpr,
+	struct expression *expr)
+{
+	trace(TR_CHECK, "assign");
+	expr->type = EXPR_ASSIGN;
+	expr->assign.indirect = aexpr->assign.indirect;
+	expr->assign.object = calloc(1, sizeof(struct expression));
+	expr->assign.value = calloc(1, sizeof(struct expression));
+
+	check_expression(ctx, aexpr->assign.object, expr->assign.object);
+	check_expression(ctx, aexpr->assign.value, expr->assign.value);
+
+	if (aexpr->assign.indirect) {
+		assert(0); // TODO
+	} else {
+		assert(expr->assign.object->type == EXPR_ACCESS); // Invariant
+		// TODO: Test assignability rules:
+		assert(expr->assign.object->result->storage == expr->assign.value->result->storage);
+	}
+}
+
+static void
 check_expr_binarithm(struct context *ctx,
 	const struct ast_expression *aexpr,
 	struct expression *expr)
@@ -262,8 +285,10 @@ check_expression(struct context *ctx,
 		check_expr_access(ctx, aexpr, expr);
 		break;
 	case EXPR_ASSERT:
-	case EXPR_ASSIGN:
 		assert(0); // TODO
+	case EXPR_ASSIGN:
+		check_expr_assign(ctx, aexpr, expr);
+		break;
 	case EXPR_BINARITHM:
 		check_expr_binarithm(ctx, aexpr, expr);
 		break;
diff --git a/src/parse.c b/src/parse.c
@@ -778,14 +778,14 @@ parse_binding_list(struct parser *par)
 }
 
 static struct ast_expression *
-parse_assignment(struct parser *par, struct ast_expression *lvalue, bool indirect)
+parse_assignment(struct parser *par, struct ast_expression *object, bool indirect)
 {
 	trenter(TR_PARSE, "assign");
-	struct ast_expression *rvalue = parse_complex_expression(par);
+	struct ast_expression *value = parse_complex_expression(par);
 	struct ast_expression *expr = calloc(1, sizeof(struct ast_expression));
 	expr->type = EXPR_ASSIGN;
-	expr->assign.lvalue = lvalue;
-	expr->assign.rvalue = rvalue;
+	expr->assign.object = object;
+	expr->assign.value = value;
 	expr->assign.indirect = indirect;
 	trleave(TR_PARSE, NULL);
 	return expr;