var last_count = 1 / 0;
for (var pass = 0; pass < passes; pass++) {
if (pass > 0 || this.option("reduce_vars"))
- node.reset_opt_flags(this, true);
+ node.reset_opt_flags(this);
node = node.transform(this);
if (passes > 1) {
var count = 0;
self.transform(tt);
});
- AST_Node.DEFMETHOD("reset_opt_flags", function(compressor, rescan) {
- var reduce_vars = rescan && compressor.option("reduce_vars");
+ AST_Node.DEFMETHOD("reset_opt_flags", function(compressor) {
+ var reduce_vars = compressor.option("reduce_vars");
+ var unused = compressor.option("unused");
// Stack of look-up tables to keep track of whether a `SymbolDef` has been
// properly assigned before use:
// - `push()` & `pop()` when visiting conditional branches
if (node instanceof AST_SymbolRef) {
var d = node.definition();
d.references.push(node);
- if (d.fixed === undefined || !safe_to_read(d)
- || is_modified(node, 0, is_immutable(node))) {
+ if (d.fixed === undefined || !safe_to_read(d) || d.single_use == "m") {
d.fixed = false;
} else {
- var parent = tw.parent();
- if (parent instanceof AST_Assign && parent.operator == "=" && node === parent.right
- || parent instanceof AST_Call && node !== parent.expression
- || parent instanceof AST_Return && node === parent.value && node.scope !== d.scope
- || parent instanceof AST_VarDef && node === parent.value) {
- d.escaped = true;
+ var value = node.fixed_value();
+ if (unused) {
+ d.single_use = value
+ && d.references.length == 1
+ && loop_ids[d.id] === in_loop
+ && d.scope === node.scope
+ && value.is_constant_expression();
+ }
+ if (is_modified(node, 0, is_immutable(value))) {
+ if (d.single_use) {
+ d.single_use = "m";
+ } else {
+ d.fixed = false;
+ }
+ } else {
+ var parent = tw.parent();
+ if (parent instanceof AST_Assign && parent.operator == "=" && node === parent.right
+ || parent instanceof AST_Call && node !== parent.expression
+ || parent instanceof AST_Return && node === parent.value && node.scope !== d.scope
+ || parent instanceof AST_VarDef && node === parent.value) {
+ d.escaped = true;
+ }
}
}
}
def.single_use = undefined;
}
- function is_immutable(node) {
- var value = node.fixed_value();
- if (!value) return false;
- if (value.is_constant()) return true;
- if (compressor.option("unused")) {
- var d = node.definition();
- if (d.single_use === undefined) {
- d.single_use = loop_ids[d.id] === in_loop
- && d.scope === node.scope
- && value.is_constant_expression();
- }
- if (d.references.length == 1 && d.single_use) return true;
- }
- return value instanceof AST_Lambda;
+ function is_immutable(value) {
+ return value && (value.is_constant() || value instanceof AST_Lambda);
}
function is_modified(node, level, immutable) {
d.fixed = fixed = make_node(AST_Function, fixed, fixed);
}
if (compressor.option("unused")
+ && fixed
&& d.references.length == 1
&& (d.single_use || fixed instanceof AST_Function
&& !(d.scope.uses_arguments && d.orig[0] instanceof AST_SymbolFunarg)