Add basic type checking

Squashed commit of WIP-type_check@5dadc4f5667ae69a709dd45c020780f2f424d67e

1 files changed, 76 insertions, 0 deletions

diff --git a/sem_check.c b/sem_check.c
index 637d044..ae1fa4c 100644
--- a/sem_check.c
+++ b/sem_check.c
@@ -34,3 +34,79 @@ char *n;
 
 	return tmp;
 }
+
+int check_ret_type(t)
+ptree *t;
+{
+	char buf[100];
+	int type;
+
+	if (!t)
+	printf("TYPE: %d\n", t->type);
+
+	switch (t->type) {
+	case ID:
+		if (!(t->attr.nval))
+			yyerror("Missing ID\n");
+
+		return t->attr.nval->var_type;
+
+	case ADDOP :
+	case MULOP :
+	case RELOP :
+		if (!(t->r && t->l))
+			yyerror("Missing nodes\n");
+
+		if (t->r->ret_type == t->l->ret_type)
+			return BOOL;
+		else
+			yyerror("Misssing nodes\n");
+		break;
+	case NOT:
+		if (t->ret_type == BOOL)
+			return BOOL;
+		yyerror("NOT needs bool input\n");
+		break;
+	case INUM:
+		printf("INUM: %d", t->attr.ival);
+		return INT;
+	case RNUM:
+		return REAL;
+	case ASSIGNOP:
+		fprintf(stderr, "HERE\n");
+		if (!(t->r && t->l && t->r->attr.nval))
+			yyerror("Incomplete parse tree\n");
+
+		if (t->l->attr.nval->var_type == t->r->ret_type)
+			return 0;
+		else {
+			snprintf(buf, 100, "Mismached types: "
+					"Cannot assign type %s "
+					"to variable \"%s\" of type %s\n",
+					pretty_type(t->r->ret_type),
+					t->l->attr.nval->name,
+					pretty_type(t->l->attr.nval->var_type));
+			yyerror(buf);
+		}
+
+
+		break;
+	case ARRAY_ACCESS:
+		if (!(t->r && t->l && t->l->attr.nval))
+			yyerror("Incorrect Array Access\n");
+
+		type = t->l->attr.nval -> var_type;
+		if (type == ARRAY - INT || type == ARRAY - REAL)
+			return 0;
+		break;
+	default:
+		return -200;
+		snprintf(buf, 101, "Unknown tree node: %d...\n", t->type);
+		yyerror(buf);
+	}
+
+
+	return -1;
+
+}
+