augment evaluate to extract within objects (#1425)

- gated by `unsafe`
- replaces previous optimisation specific to String.length
- "123"[0] => 1
- [1, 2, 3][0] => 1
- [1, 2, 3].length => 3
- does not apply to objects with overridden prototype functions
This commit is contained in:
Alex Lam S.L
2017-01-26 19:14:18 +08:00
committed by Richard van Velzen
parent 48284844a4
commit 0d7d4918eb
6 changed files with 729 additions and 14 deletions

View File

@@ -152,6 +152,12 @@ merge(Compressor.prototype, {
AST_Node.DEFMETHOD("clear_opt_flags", function(){
this.walk(new TreeWalker(function(node){
if (node instanceof AST_SymbolRef) {
var d = node.definition();
if (d && d.init) {
delete d.init._evaluated;
}
}
if (!(node instanceof AST_Directive || node instanceof AST_Constant)) {
node._squeezed = false;
node._optimized = false;
@@ -992,13 +998,20 @@ merge(Compressor.prototype, {
// constant; otherwise it's the original or a replacement node.
AST_Node.DEFMETHOD("evaluate", function(compressor){
if (!compressor.option("evaluate")) return [ this ];
var val;
try {
var val = this._eval(compressor);
return [ best_of(make_node_from_constant(compressor, val, this), this), val ];
val = this._eval(compressor);
} catch(ex) {
if (ex !== def) throw ex;
return [ this ];
}
var node;
try {
node = make_node_from_constant(compressor, val, this);
} catch(ex) {
return [ this ];
}
return [ best_of(node, this), val ];
});
AST_Node.DEFMETHOD("is_constant", function(compressor){
// Accomodate when compress option evaluate=false
@@ -1047,6 +1060,32 @@ merge(Compressor.prototype, {
def(AST_Constant, function(){
return this.getValue();
});
def(AST_Array, function(compressor){
if (compressor.option("unsafe")) {
return this.elements.map(function(element) {
return ev(element, compressor);
});
}
throw def;
});
def(AST_Object, function(compressor){
if (compressor.option("unsafe")) {
var val = {};
for (var i = 0, len = this.properties.length; i < len; i++) {
var prop = this.properties[i];
var key = prop.key;
if (key instanceof AST_Node) {
key = ev(key, compressor);
}
if (typeof Object.prototype[key] === 'function') {
throw def;
}
val[key] = ev(prop.value, compressor);
}
return val;
}
throw def;
});
def(AST_UnaryPrefix, function(compressor){
var e = this.expression;
switch (this.operator) {
@@ -1114,6 +1153,12 @@ merge(Compressor.prototype, {
try {
var d = this.definition();
if (d && (d.constant || compressor.option("reduce_vars") && !d.modified) && d.init) {
if (compressor.option("unsafe")) {
if (!HOP(d.init, '_evaluated')) {
d.init._evaluated = ev(d.init, compressor);
}
return d.init._evaluated;
}
return ev(d.init, compressor);
}
} finally {
@@ -1121,11 +1166,16 @@ merge(Compressor.prototype, {
}
throw def;
});
def(AST_Dot, function(compressor){
if (compressor.option("unsafe") && this.property == "length") {
var str = ev(this.expression, compressor);
if (typeof str == "string")
return str.length;
def(AST_PropAccess, function(compressor){
if (compressor.option("unsafe")) {
var key = this.property;
if (key instanceof AST_Node) {
key = ev(key, compressor);
}
var val = ev(this.expression, compressor);
if (val && HOP(val, key)) {
return val[key];
}
}
throw def;
});
@@ -2890,7 +2940,7 @@ merge(Compressor.prototype, {
});
}
}
return self;
return self.evaluate(compressor)[0];
});
OPT(AST_Dot, function(self, compressor){

View File

@@ -184,6 +184,17 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(options){
var func = null;
var globals = self.globals = new Dictionary();
var tw = new TreeWalker(function(node, descend){
function isModified(node, level) {
var parent = tw.parent(level);
if (parent instanceof AST_Unary && (parent.operator === "++" || parent.operator === "--")
|| parent instanceof AST_Assign && parent.left === node
|| parent instanceof AST_Call && parent.expression === node) {
return true;
} else if (parent instanceof AST_PropAccess && parent.expression === node) {
return isModified(parent, level + 1);
}
}
if (node instanceof AST_Lambda) {
var prev_func = func;
func = node;
@@ -197,8 +208,7 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(options){
}
if (node instanceof AST_SymbolRef) {
var name = node.name;
var parent = tw.parent();
if (name == "eval" && parent instanceof AST_Call) {
if (name == "eval" && tw.parent() instanceof AST_Call) {
for (var s = node.scope; s && !s.uses_eval; s = s.parent_scope) {
s.uses_eval = true;
}
@@ -220,8 +230,7 @@ AST_Toplevel.DEFMETHOD("figure_out_scope", function(options){
sym = g;
}
node.thedef = sym;
if (parent instanceof AST_Unary && (parent.operator === "++" || parent.operator === "--")
|| parent instanceof AST_Assign && parent.left === node) {
if (isModified(node, 0)) {
sym.modified = true;
}
node.reference();

View File

@@ -72,3 +72,52 @@ constant_join_2: {
var f = "strstr" + variable + "foobarmoo" + foo;
}
}
for_loop: {
options = {
unsafe : true,
evaluate : true,
reduce_vars : true
};
input: {
function f0() {
var a = [1, 2, 3];
for (var i = 0; i < a.length; i++) {
console.log(a[i]);
}
}
function f1() {
var a = [1, 2, 3];
for (var i = 0, len = a.length; i < len; i++) {
console.log(a[i]);
}
}
function f2() {
var a = [1, 2, 3];
for (var i = 0; i < a.length; i++) {
a[i]++;
}
}
}
expect: {
function f0() {
var a = [1, 2, 3];
for (var i = 0; i < 3; i++)
console.log(a[i]);
}
function f1() {
var a = [1, 2, 3];
for (var i = 0, len = 3; i < len; i++)
console.log(a[i]);
}
function f2() {
var a = [1, 2, 3];
for (var i = 0; i < a.length; i++)
a[i]++;
}
}
}

View File

@@ -37,3 +37,380 @@ positive_zero: {
);
}
}
unsafe_constant: {
options = {
evaluate : true,
unsafe : true
}
input: {
console.log(
true.a,
false.a,
null.a,
undefined.a
);
}
expect: {
console.log(
true.a,
false.a,
null.a,
(void 0).a
);
}
}
unsafe_object: {
options = {
evaluate : true,
unsafe : true
}
input: {
console.log(
({a:1}) + 1,
({a:1}).a + 1,
({a:1}).b + 1,
({a:1}).a.b + 1
);
}
expect: {
console.log(
({a:1}) + 1,
2,
({a:1}).b + 1,
1..b + 1
);
}
}
unsafe_object_nested: {
options = {
evaluate : true,
unsafe : true
}
input: {
console.log(
({a:{b:1}}) + 1,
({a:{b:1}}).a + 1,
({a:{b:1}}).b + 1,
({a:{b:1}}).a.b + 1
);
}
expect: {
console.log(
({a:{b:1}}) + 1,
({a:{b:1}}).a + 1,
({a:{b:1}}).b + 1,
2
);
}
}
unsafe_object_complex: {
options = {
evaluate : true,
unsafe : true
}
input: {
console.log(
({a:{b:1},b:1}) + 1,
({a:{b:1},b:1}).a + 1,
({a:{b:1},b:1}).b + 1,
({a:{b:1},b:1}).a.b + 1
);
}
expect: {
console.log(
({a:{b:1},b:1}) + 1,
({a:{b:1},b:1}).a + 1,
2,
2
);
}
}
unsafe_object_repeated: {
options = {
evaluate : true,
unsafe : true
}
input: {
console.log(
({a:{b:1},a:1}) + 1,
({a:{b:1},a:1}).a + 1,
({a:{b:1},a:1}).b + 1,
({a:{b:1},a:1}).a.b + 1
);
}
expect: {
console.log(
({a:{b:1},a:1}) + 1,
2,
({a:{b:1},a:1}).b + 1,
1..b + 1
);
}
}
unsafe_function: {
options = {
evaluate : true,
unsafe : true
}
input: {
console.log(
({a:{b:1},b:function(){}}) + 1,
({a:{b:1},b:function(){}}).a + 1,
({a:{b:1},b:function(){}}).b + 1,
({a:{b:1},b:function(){}}).a.b + 1
);
}
expect: {
console.log(
({a:{b:1},b:function(){}}) + 1,
({a:{b:1},b:function(){}}).a + 1,
({a:{b:1},b:function(){}}).b + 1,
({a:{b:1},b:function(){}}).a.b + 1
);
}
}
unsafe_integer_key: {
options = {
evaluate : true,
unsafe : true
}
input: {
console.log(
({0:1}) + 1,
({0:1})[0] + 1,
({0:1})["0"] + 1,
({0:1})[1] + 1,
({0:1})[0][1] + 1,
({0:1})[0]["1"] + 1
);
}
expect: {
console.log(
({0:1}) + 1,
2,
2,
({0:1})[1] + 1,
1[1] + 1,
1["1"] + 1
);
}
}
unsafe_integer_key_complex: {
options = {
evaluate : true,
unsafe : true
}
input: {
console.log(
({0:{1:1},1:1}) + 1,
({0:{1:1},1:1})[0] + 1,
({0:{1:1},1:1})["0"] + 1,
({0:{1:1},1:1})[1] + 1,
({0:{1:1},1:1})[0][1] + 1,
({0:{1:1},1:1})[0]["1"] + 1
);
}
expect: {
console.log(
({0:{1:1},1:1}) + 1,
"[object Object]1",
"[object Object]1",
2,
2,
2
);
}
}
unsafe_float_key: {
options = {
evaluate : true,
unsafe : true
}
input: {
console.log(
({2.72:1}) + 1,
({2.72:1})[2.72] + 1,
({2.72:1})["2.72"] + 1,
({2.72:1})[3.14] + 1,
({2.72:1})[2.72][3.14] + 1,
({2.72:1})[2.72]["3.14"] + 1
);
}
expect: {
console.log(
({2.72:1}) + 1,
2,
2,
({2.72:1})[3.14] + 1,
1[3.14] + 1,
1["3.14"] + 1
);
}
}
unsafe_float_key_complex: {
options = {
evaluate : true,
unsafe : true
}
input: {
console.log(
({2.72:{3.14:1},3.14:1}) + 1,
({2.72:{3.14:1},3.14:1})[2.72] + 1,
({2.72:{3.14:1},3.14:1})["2.72"] + 1,
({2.72:{3.14:1},3.14:1})[3.14] + 1,
({2.72:{3.14:1},3.14:1})[2.72][3.14] + 1,
({2.72:{3.14:1},3.14:1})[2.72]["3.14"] + 1
);
}
expect: {
console.log(
"[object Object]1",
"[object Object]1",
"[object Object]1",
2,
2,
2
);
}
}
unsafe_array: {
options = {
evaluate : true,
unsafe : true
}
input: {
console.log(
[1, , 3][1],
[1, 2, 3, a] + 1,
[1, 2, 3, 4] + 1,
[1, 2, 3, a][0] + 1,
[1, 2, 3, 4][0] + 1,
[1, 2, 3, 4][6 - 5] + 1,
[1, , 3, 4][6 - 5] + 1,
[[1, 2], [3, 4]][0] + 1,
[[1, 2], [3, 4]][6 - 5][1] + 1,
[[1, 2], , [3, 4]][6 - 5][1] + 1
);
}
expect: {
console.log(
void 0,
[1, 2, 3, a] + 1,
"1,2,3,41",
[1, 2, 3, a][0] + 1,
2,
3,
NaN,
"1,21",
5,
(void 0)[1] + 1
);
}
}
unsafe_string: {
options = {
evaluate : true,
unsafe : true
}
input: {
console.log(
"1234" + 1,
"1234"[0] + 1,
"1234"[6 - 5] + 1,
("12" + "34")[0] + 1,
("12" + "34")[6 - 5] + 1,
[1, 2, 3, 4].join("")[0] + 1
);
}
expect: {
console.log(
"12341",
"11",
"21",
"11",
"21",
"11"
);
}
}
unsafe_array_bad_index: {
options = {
evaluate : true,
unsafe : true
}
input: {
console.log(
[1, 2, 3, 4].a + 1,
[1, 2, 3, 4]["a"] + 1,
[1, 2, 3, 4][3.14] + 1
);
}
expect: {
console.log(
[1, 2, 3, 4].a + 1,
[1, 2, 3, 4]["a"] + 1,
[1, 2, 3, 4][3.14] + 1
);
}
}
unsafe_string_bad_index: {
options = {
evaluate : true,
unsafe : true
}
input: {
console.log(
"1234".a + 1,
"1234"["a"] + 1,
"1234"[3.14] + 1
);
}
expect: {
console.log(
"1234".a + 1,
"1234"["a"] + 1,
"1234"[3.14] + 1
);
}
}
unsafe_prototype_function: {
options = {
evaluate : true,
unsafe : true
}
input: {
var a = ({valueOf: 0}) < 1;
var b = ({toString: 0}) < 1;
var c = ({valueOf: 0}) + "";
var d = ({toString: 0}) + "";
var e = (({valueOf: 0}) + "")[2];
var f = (({toString: 0}) + "")[2];
var g = ({valueOf: 0}).valueOf();
var h = ({toString: 0}).toString();
}
expect: {
var a = ({valueOf: 0}) < 1;
var b = ({toString: 0}) < 1;
var c = ({valueOf: 0}) + "";
var d = ({toString: 0}) + "";
var e = (({valueOf: 0}) + "")[2];
var f = (({toString: 0}) + "")[2];
var g = ({valueOf: 0}).valueOf();
var h = "" + ({toString: 0});
}
}

View File

@@ -54,7 +54,56 @@ dot_properties_es5: {
}
}
evaluate_length: {
sub_properties: {
options = {
evaluate: true,
properties: true
};
input: {
a[0] = 0;
a["0"] = 1;
a[3.14] = 2;
a["3" + ".14"] = 3;
a["i" + "f"] = 4;
a["foo" + " bar"] = 5;
a[0 / 0] = 6;
a[null] = 7;
a[undefined] = 8;
}
expect: {
a[0] = 0;
a[0] = 1;
a[3.14] = 2;
a[3.14] = 3;
a.if = 4;
a["foo bar"] = 5;
a[NaN] = 6;
a[null] = 7;
a[void 0] = 8;
}
}
evaluate_array_length: {
options = {
properties: true,
unsafe: true,
evaluate: true
};
input: {
a = [1, 2, 3].length;
a = [1, 2, 3].join()["len" + "gth"];
a = [1, 2, b].length;
a = [1, 2, 3].join(b).length;
}
expect: {
a = 3;
a = 5;
a = [1, 2, b].length;
a = [1, 2, 3].join(b).length;
}
}
evaluate_string_length: {
options = {
properties: true,
unsafe: true,

View File

@@ -169,3 +169,184 @@ modified: {
}
}
}
unsafe_evaluate: {
options = {
evaluate : true,
reduce_vars : true,
unsafe : true,
unused : true
}
input: {
function f0(){
var a = {
b:1
};
console.log(a.b + 3);
}
function f1(){
var a = {
b:{
c:1
},
d:2
};
console.log(a.b + 3, a.d + 4, a.b.c + 5, a.d.c + 6);
}
}
expect: {
function f0(){
console.log(4);
}
function f1(){
var a = {
b:{
c:1
},
d:2
};
console.log(a.b + 3, 6, 6, 2..c + 6);
}
}
}
unsafe_evaluate_object: {
options = {
evaluate : true,
reduce_vars : true,
unsafe : true
}
input: {
function f0(){
var a = 1;
var b = {};
b[a] = 2;
console.log(a + 3);
}
function f1(){
var a = {
b:1
};
a.b = 2;
console.log(a.b + 3);
}
}
expect: {
function f0(){
var a = 1;
var b = {};
b[a] = 2;
console.log(4);
}
function f1(){
var a = {
b:1
};
a.b = 2;
console.log(a.b + 3);
}
}
}
unsafe_evaluate_array: {
options = {
evaluate : true,
reduce_vars : true,
unsafe : true
}
input: {
function f0(){
var a = 1;
var b = [];
b[a] = 2;
console.log(a + 3);
}
function f1(){
var a = [1];
a[2] = 3;
console.log(a.length);
}
function f2(){
var a = [1];
a.push(2);
console.log(a.length);
}
}
expect: {
function f0(){
var a = 1;
var b = [];
b[a] = 2;
console.log(4);
}
function f1(){
var a = [1];
a[2] = 3;
console.log(a.length);
}
function f2(){
var a = [1];
a.push(2);
console.log(a.length);
}
}
}
unsafe_evaluate_equality: {
options = {
evaluate : true,
reduce_vars : true,
unsafe : true,
unused : true
}
input: {
function f0(){
var a = {};
console.log(a === a);
}
function f1(){
var a = [];
console.log(a === a);
}
function f2(){
var a = {a:1, b:2};
var b = a;
var c = a;
console.log(b === c);
}
function f3(){
var a = [1, 2, 3];
var b = a;
var c = a;
console.log(b === c);
}
}
expect: {
function f0(){
console.log(true);
}
function f1(){
console.log(true);
}
function f2(){
console.log(true);
}
function f3(){
console.log(true);
}
}
}