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Merge branch 'master' into harmony-v3.0.23

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This commit is contained in:
alexlamsl
2017-07-02 17:47:21 +08:00
parent a9eecd844f 2dde41615a
commit e77b6d525c
8 changed files with 182 additions and 96 deletions
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149
lib/compress.js
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@@ -749,15 +749,23 @@ merge(Compressor.prototype, {
var candidates = [];
var stat_index = statements.length;
while (--stat_index >= 0) {
// Treat parameters as collapsible in IIFE, i.e.
// function(a, b){ ... }(x());
// would be translated into equivalent assignments:
// var a = x(), b = undefined;
if (stat_index == 0 && compressor.option("unused")) extract_args();
// Find collapsible assignments
extract_candidates(statements[stat_index]);
while (candidates.length > 0) {
var candidate = candidates.pop();
var lhs = get_lhs(candidate);
if (!lhs || is_lhs_read_only(lhs)) continue;
// Locate symbols which may execute code outside of scanning range
var lvalues = get_lvalues(candidate);
if (lhs instanceof AST_SymbolRef) lvalues[lhs.name] = false;
var side_effects = value_has_side_effects(candidate);
var hit = false, abort = false, replaced = false;
var hit = candidate.name instanceof AST_SymbolFunarg;
var abort = false, replaced = false;
var tt = new TreeTransformer(function(node, descend) {
if (abort) return node;
// Skip nodes before `candidate` as quickly as possible
@@ -840,6 +848,39 @@ merge(Compressor.prototype, {
}
}
function extract_args() {
var iife, fn = compressor.self();
if (is_func_expr(fn)
&& !fn.name
&& !fn.uses_arguments
&& !fn.uses_eval
&& (iife = compressor.parent()) instanceof AST_Call
&& iife.expression === fn
&& all(iife.args, function(arg) {
return !(arg instanceof AST_Expansion);
})) {
fn.argnames.forEach(function(sym, i) {
if (!(sym instanceof AST_SymbolFunarg)) return;
var arg = iife.args[i];
if (!arg) arg = make_node(AST_Undefined, sym);
else arg.walk(new TreeWalker(function(node) {
if (!arg) return true;
if (node instanceof AST_SymbolRef && fn.variables.has(node.name)) {
var s = node.definition().scope;
if (s !== scope) while (s = s.parent_scope) {
if (s === scope) return true;
}
arg = null;
}
}));
if (arg) candidates.push(make_node(AST_VarDef, sym, {
name: sym,
value: arg
}));
});
}
}
function extract_candidates(expr) {
if (expr instanceof AST_Assign && !expr.left.has_side_effects(compressor)
|| expr instanceof AST_Unary && (expr.operator == "++" || expr.operator == "--")) {
@@ -860,7 +901,7 @@ merge(Compressor.prototype, {
function get_lhs(expr) {
if (expr instanceof AST_VarDef && expr.name instanceof AST_SymbolDeclaration) {
var def = expr.name.definition();
if (def.orig.length > 1
if (def.orig.length > 1 && !(expr.name instanceof AST_SymbolFunarg)
|| def.references.length == 1 && !compressor.exposed(def)) {
return make_node(AST_SymbolRef, expr.name, expr.name);
}
@@ -903,6 +944,14 @@ merge(Compressor.prototype, {
}
function remove_candidate(expr) {
if (expr.name instanceof AST_SymbolFunarg) {
var index = compressor.self().argnames.indexOf(expr.name);
var args = compressor.parent().args;
if (args[index]) args[index] = make_node(AST_Number, args[index], {
value: 0
});
return true;
}
var found = false;
return statements[stat_index].transform(new TreeTransformer(function(node, descend, in_list) {
if (found) return node;
@@ -3343,98 +3392,54 @@ merge(Compressor.prototype, {
var value = stat.value;
if (!value || value.is_constant_expression()) {
var args = self.args.concat(value || make_node(AST_Undefined, self));
return make_sequence(self, args).transform(compressor);
return make_sequence(self, args).optimize(compressor);
}
}
if (is_func_expr(exp) && !exp.is_generator && !exp.async) {
if (compressor.option("inline")
&& simple_args
&& !exp.name
&& (exp.body instanceof AST_Node || exp.body.length == 1)
&& !exp.uses_arguments
&& !exp.uses_eval
&& simple_args
&& (exp.body instanceof AST_Node || exp.body.length == 1)
&& all(exp.argnames, function(arg) {
return arg.__unused;
})
&& !self.has_pure_annotation(compressor)) {
var value;
if (stat instanceof AST_Return) {
value = stat.value.clone(true);
value = stat.value;
} else if (stat instanceof AST_SimpleStatement) {
value = make_node(AST_UnaryPrefix, stat, {
operator: "void",
expression: stat.body.clone(true)
expression: stat.body
});
}
if (value) {
var fn = exp.clone();
fn.argnames = [];
fn.body = [];
if (exp.argnames.length > 0) {
fn.body.push(make_node(AST_Var, self, {
definitions: exp.argnames.map(function(sym, i) {
if (sym instanceof AST_Expansion) {
return make_node(AST_VarDef, sym, {
name: sym.expression,
value: make_node(AST_Array, self, {
elements: self.args.slice(i).map(function(arg) {
return arg.clone(true);
})
})
});
}
var arg = self.args[i];
return make_node(AST_VarDef, sym, {
name: sym,
value: arg ? arg.clone(true) : make_node(AST_Undefined, self)
});
})
}));
}
if (self.args.length > exp.argnames.length && !(exp.argnames[exp.argnames.length - 1] instanceof AST_Expansion)) {
fn.body.push(make_node(AST_SimpleStatement, self, {
body: make_sequence(self, self.args.slice(exp.argnames.length).map(function(node) {
return node.clone(true);
}))
}));
}
fn.body.push(make_node(AST_Return, self, {
value: value
}));
var body = fn.transform(compressor).body;
if (body instanceof AST_Node) {
body = [
make_node(AST_Return, body, {
value: body
})
];
}
if (body.length == 0) return make_node(AST_Undefined, self);
if (body.length == 1 && body[0] instanceof AST_Return) {
value = body[0].value;
if (!value) return make_node(AST_Undefined, self);
var tw = new TreeWalker(function(node) {
if (value === self) return true;
if (node instanceof AST_SymbolRef) {
var ref = node.scope.find_variable(node);
if (ref && ref.scope.parent_scope === fn.parent_scope) {
value = self;
return true;
}
}
if (node instanceof AST_This && !tw.find_parent(AST_Scope)) {
value = self;
var tw = new TreeWalker(function(node) {
if (!value) return true;
if (node instanceof AST_SymbolRef) {
var ref = node.scope.find_variable(node);
if (ref && ref.scope.parent_scope === fn.parent_scope) {
value = null;
return true;
}
});
value.walk(tw);
if (value !== self) value = best_of(compressor, value, self);
} else {
value = self;
}
if (value !== self) return value;
}
if (node instanceof AST_This && !tw.find_parent(AST_Scope)) {
value = null;
return true;
}
});
value.walk(tw);
}
if (value) {
var args = self.args.concat(value);
return make_sequence(self, args).optimize(compressor);
}
}
if (compressor.option("side_effects") && !(exp.body instanceof AST_Node) && all(exp.body, is_empty)) {
var args = self.args.concat(make_node(AST_Undefined, self));
return make_sequence(self, args).transform(compressor);
return make_sequence(self, args).optimize(compressor);
}
}
if (compressor.option("drop_console")) {