diff --git a/src/oberon.c b/src/oberon.c
index e8cbf428c12a7261b90dd057c8dc96381f465a3b..f50f4d300246b4beed4fd6e58afaf21cb307cf3a 100644 (file)
--- a/src/oberon.c
+++ b/src/oberon.c
WHILE,
DO,
REPEAT,
- UNTIL
+ UNTIL,
+ FOR,
+ BY
};
// =======================================================================
return result;
}
+static oberon_object_t *
+oberon_create_object(oberon_scope_t * scope, char * name, int class, bool export, bool read_only)
+{
+ oberon_object_t * newvar = malloc(sizeof *newvar);
+ memset(newvar, 0, sizeof *newvar);
+ newvar -> name = name;
+ newvar -> class = class;
+ newvar -> export = export;
+ newvar -> read_only = read_only;
+ newvar -> local = scope -> local;
+ newvar -> parent = scope -> parent;
+ newvar -> parent_type = scope -> parent_type;
+ newvar -> module = scope -> ctx -> mod;
+ return newvar;
+}
+
static oberon_object_t *
oberon_define_object(oberon_scope_t * scope, char * name, int class, bool export, bool read_only, bool check_upscope)
{
@@ -229,17 +247,8 @@ oberon_define_object(oberon_scope_t * scope, char * name, int class, bool export
oberon_error(scope -> ctx, "already defined");
}
- oberon_object_t * newvar = malloc(sizeof *newvar);
- memset(newvar, 0, sizeof *newvar);
- newvar -> name = name;
- newvar -> class = class;
- newvar -> export = export;
- newvar -> read_only = read_only;
- newvar -> local = scope -> local;
- newvar -> parent = scope -> parent;
- newvar -> parent_type = scope -> parent_type;
- newvar -> module = scope -> ctx -> mod;
-
+ oberon_object_t * newvar;
+ newvar = oberon_create_object(scope, name, class, export, read_only);
x -> next = newvar;
return newvar;
{
ctx -> token = UNTIL;
}
+ else if(strcmp(ident, "FOR") == 0)
+ {
+ ctx -> token = FOR;
+ }
+ else if(strcmp(ident, "BY") == 0)
+ {
+ ctx -> token = BY;
+ }
}
static void
return x;
}
+static oberon_expr_t *
+oberon_ident_item(oberon_context_t * ctx, char * name)
+{
+ bool read_only;
+ oberon_object_t * x;
+ oberon_expr_t * expr;
+
+ x = oberon_find_object(ctx -> decl, name, true);
+
+ read_only = false;
+ if(x -> class == OBERON_CLASS_CONST || x -> class == OBERON_CLASS_PROC)
+ {
+ read_only = true;
+ }
+
+ expr = oberon_new_item(MODE_VAR, x -> type, read_only);
+ expr -> item.var = x;
+ return expr;
+}
+
static oberon_expr_t *
oberon_designator(oberon_context_t * ctx)
{
expr = oberon_new_item(MODE_VAR, var -> type, read_only);
break;
case OBERON_CLASS_PROC:
- expr = oberon_new_item(MODE_VAR, var -> type, 1);
+ expr = oberon_new_item(MODE_VAR, var -> type, true);
break;
default:
oberon_error(ctx, "invalid designator");
}
}
+static oberon_expr_t *
+oberon_integer_item(oberon_context_t * ctx, int64_t i)
+{
+ oberon_expr_t * expr;
+ oberon_type_t * result;
+ result = oberon_get_type_of_int_value(ctx, i);
+ expr = oberon_new_item(MODE_INTEGER, result, true);
+ expr -> item.integer = i;
+ return expr;
+}
+
static oberon_expr_t *
oberon_factor(oberon_context_t * ctx)
{
expr = oberon_opt_func_parens(ctx, expr);
break;
case INTEGER:
- result = oberon_get_type_of_int_value(ctx, ctx -> integer);
- expr = oberon_new_item(MODE_INTEGER, result, true);
- expr -> item.integer = ctx -> integer;
+ expr = oberon_integer_item(ctx, ctx -> integer);
oberon_assert_token(ctx, INTEGER);
break;
case CHAR:
oberon_error(ctx, "const expression are required");
}
+ switch(expr -> item.mode)
+ {
+ case MODE_INTEGER:
+ case MODE_BOOLEAN:
+ case MODE_NIL:
+ case MODE_REAL:
+ case MODE_CHAR:
+ case MODE_STRING:
+ /* accept */
+ break;
+ default:
+ oberon_error(ctx, "const expression are required");
+ break;
+ }
+
return (oberon_item_t *) expr;
}
oberon_prevent_undeclarated_procedures(ctx);
}
+static oberon_expr_t *
+oberon_make_temp_var_item(oberon_context_t * ctx, oberon_type_t * type)
+{
+ oberon_object_t * x;
+ oberon_expr_t * expr;
+
+ x = oberon_create_object(ctx -> decl, "TEMP", OBERON_CLASS_VAR, false, false);
+ x -> local = true;
+ x -> type = type;
+ oberon_generator_init_temp_var(ctx, x);
+
+ expr = oberon_new_item(MODE_VAR, type, false);
+ expr -> item.var = x;
+ return expr;
+}
+
static void
oberon_statement_seq(oberon_context_t * ctx);
oberon_generate_branch(ctx, cond, true, begin);
}
+ else if(ctx -> token == FOR)
+ {
+ oberon_expr_t * from;
+ oberon_expr_t * index;
+ oberon_expr_t * to;
+ oberon_expr_t * bound;
+ oberon_expr_t * by;
+ oberon_expr_t * cond;
+ oberon_expr_t * count;
+ gen_label_t * begin;
+ gen_label_t * end;
+ char * iname;
+ int op;
+
+ begin = oberon_generator_reserve_label(ctx);
+ end = oberon_generator_reserve_label(ctx);
+
+ oberon_assert_token(ctx, FOR);
+ iname = oberon_assert_ident(ctx);
+ index = oberon_ident_item(ctx, iname);
+ oberon_assert_token(ctx, ASSIGN);
+ from = oberon_expr(ctx);
+ oberon_assign(ctx, from, index);
+ oberon_assert_token(ctx, TO);
+ bound = oberon_make_temp_var_item(ctx, index -> result);
+ to = oberon_expr(ctx);
+ oberon_assign(ctx, to, bound);
+ if(ctx -> token == BY)
+ {
+ oberon_assert_token(ctx, BY);
+ by = (oberon_expr_t *) oberon_const_expr(ctx);
+ }
+ else
+ {
+ by = oberon_integer_item(ctx, 1);
+ }
+
+ if(by -> result -> class != OBERON_TYPE_INTEGER)
+ {
+ oberon_error(ctx, "must be integer");
+ }
+
+ if(by -> item.integer > 0)
+ {
+ op = LEQ;
+ }
+ else if(by -> item.integer < 0)
+ {
+ op = GEQ;
+ }
+ else
+ {
+ oberon_error(ctx, "zero step not allowed");
+ }
+
+ oberon_assert_token(ctx, DO);
+ oberon_generate_label(ctx, begin);
+ cond = oberon_make_bin_op(ctx, op, index, bound);
+ oberon_generate_branch(ctx, cond, false, end);
+ oberon_statement_seq(ctx);
+ count = oberon_make_bin_op(ctx, PLUS, index, by);
+ oberon_assign(ctx, count, index);
+ oberon_generate_goto(ctx, begin);
+ oberon_generate_label(ctx, end);
+ oberon_assert_token(ctx, END);
+ }
else if(ctx -> token == RETURN)
{
oberon_assert_token(ctx, RETURN);