enhance hoist_props & reduce_vars (#5183)

closes #5182
This commit is contained in:
Alex Lam S.L
2021-11-22 16:31:10 +00:00
committed by GitHub
parent 1e3ca4c6f7
commit 3ee1b0d00d
3 changed files with 65 additions and 22 deletions

View File

@@ -703,6 +703,7 @@ merge(Compressor.prototype, {
if (depth > 1 && !(value && value.is_constant_expression(scope))) depth = 1; if (depth > 1 && !(value && value.is_constant_expression(scope))) depth = 1;
if (!d.escaped.depth || d.escaped.depth > depth) d.escaped.depth = depth; if (!d.escaped.depth || d.escaped.depth > depth) d.escaped.depth = depth;
if (d.scope.resolve() !== scope.resolve()) d.escaped.cross_scope = true; if (d.scope.resolve() !== scope.resolve()) d.escaped.cross_scope = true;
if (d.fixed) d.fixed.escaped = d.escaped;
return; return;
} else if (value_in_use(node, parent)) { } else if (value_in_use(node, parent)) {
mark_escaped(tw, d, scope, parent, parent, level + 1, depth); mark_escaped(tw, d, scope, parent, parent, level + 1, depth);
@@ -720,6 +721,7 @@ merge(Compressor.prototype, {
if (parent instanceof AST_SimpleStatement) return; if (parent instanceof AST_SimpleStatement) return;
if (parent instanceof AST_Unary && !unary_side_effects[parent.operator]) return; if (parent instanceof AST_Unary && !unary_side_effects[parent.operator]) return;
d.direct_access = true; d.direct_access = true;
if (d.fixed) d.fixed.direct_access = true;
} }
function mark_assignment_to_arguments(node) { function mark_assignment_to_arguments(node) {
@@ -1000,9 +1002,9 @@ merge(Compressor.prototype, {
d.single_use = false; d.single_use = false;
} }
tw.loop_ids[d.id] = tw.in_loop; tw.loop_ids[d.id] = tw.in_loop;
mark_escaped(tw, d, sym.scope, node, right, 0, 1);
sym.fixed = d.fixed = fixed; sym.fixed = d.fixed = fixed;
sym.fixed.assigns = [ node ]; sym.fixed.assigns = [ node ];
mark_escaped(tw, d, sym.scope, node, right, 0, 1);
} }
}); });
} }
@@ -7678,6 +7680,7 @@ merge(Compressor.prototype, {
right: prop.value, right: prop.value,
})); }));
}); });
defs.value = node.right;
defs_by_id[node.left.definition().id] = defs; defs_by_id[node.left.definition().id] = defs;
self.body.splice(self.body.indexOf(this.stack[1]) + 1, 0, make_node(AST_Var, node, { self.body.splice(self.body.indexOf(this.stack[1]) + 1, 0, make_node(AST_Var, node, {
definitions: decls, definitions: decls,
@@ -7690,12 +7693,16 @@ merge(Compressor.prototype, {
descend(node, this); descend(node, this);
var defs = new Dictionary(); var defs = new Dictionary();
var var_defs = []; var var_defs = [];
var decl = node.clone();
decl.value = node.name instanceof AST_SymbolConst ? make_node(AST_Number, node, { value: 0 }) : null;
var_defs.push(decl);
node.value.properties.forEach(function(prop) { node.value.properties.forEach(function(prop) {
var_defs.push(make_node(AST_VarDef, node, { var_defs.push(make_node(AST_VarDef, node, {
name: make_sym(node.name.CTOR, node.name, prop.key), name: make_sym(node.name.CTOR, node.name, prop.key),
value: prop.value, value: prop.value,
})); }));
}); });
defs.value = node.value;
defs_by_id[node.name.definition().id] = defs; defs_by_id[node.name.definition().id] = defs;
return List.splice(var_defs); return List.splice(var_defs);
} }
@@ -7711,6 +7718,7 @@ merge(Compressor.prototype, {
if (!(node.expression instanceof AST_SymbolRef)) return; if (!(node.expression instanceof AST_SymbolRef)) return;
var defs = defs_by_id[node.expression.definition().id]; var defs = defs_by_id[node.expression.definition().id];
if (!defs) return; if (!defs) return;
if (node.expression.fixed_value() !== defs.value) return;
var def = defs.get(node.get_property()); var def = defs.get(node.get_property());
var sym = make_node(AST_SymbolRef, node, { var sym = make_node(AST_SymbolRef, node, {
name: def.name, name: def.name,
@@ -7721,7 +7729,9 @@ merge(Compressor.prototype, {
return sym; return sym;
} }
if (node instanceof AST_SymbolRef) { if (node instanceof AST_SymbolRef) {
if (!(node.definition().id in defs_by_id)) return; var defs = defs_by_id[node.definition().id];
if (!defs) return;
if (node.fixed_value() !== defs.value) return;
return make_node(AST_Object, node, { properties: [] }); return make_node(AST_Object, node, { properties: [] });
} }
})); }));
@@ -7730,18 +7740,16 @@ merge(Compressor.prototype, {
if (!(sym instanceof AST_Symbol)) return; if (!(sym instanceof AST_Symbol)) return;
var def = sym.definition(); var def = sym.definition();
if (def.assignments != count) return; if (def.assignments != count) return;
if (def.direct_access) return;
if (def.escaped.depth == 1) return;
if (def.references.length - def.replaced == count) return; if (def.references.length - def.replaced == count) return;
if (def.single_use) return; if (def.single_use) return;
if (top_retain(def)) return; if (top_retain(def)) return;
if (sym.fixed_value() !== right) return; if (sym.fixed_value() !== right) return;
var fixed = sym.fixed || def.fixed;
if (fixed.direct_access) return;
if (fixed.escaped && fixed.escaped.depth == 1) return;
return right instanceof AST_Object return right instanceof AST_Object
&& right.properties.length > 0 && right.properties.length > 0
&& all(right.properties, can_hoist_property) && all(right.properties, can_hoist_property)
&& all(def.references, function(ref) {
return ref.fixed_value() === right;
})
&& can_drop_symbol(sym, compressor); && can_drop_symbol(sym, compressor);
} }
}); });

View File

@@ -217,7 +217,8 @@ name_collision_1: {
var obj_foo = 1; var obj_foo = 1;
var obj_bar = 2; var obj_bar = 2;
function f() { function f() {
var obj_foo$0 = 3, var obj,
obj_foo$0 = 3,
obj_bar = 4, obj_bar = 4,
obj_b_r = 5, obj_b_r = 5,
obj_b_r$0 = 6, obj_b_r$0 = 6,
@@ -249,7 +250,8 @@ name_collision_2: {
console.log(o.p === o.p, o["+"](4), o["-"](5), o__$0, o__$1); console.log(o.p === o.p, o["+"](4), o["-"](5), o__$0, o__$1);
} }
expect: { expect: {
var o_p = 1, var o,
o_p = 1,
o__ = function(x) { o__ = function(x) {
return x; return x;
}, },
@@ -283,7 +285,8 @@ name_collision_3: {
console.log(o.p === o.p, o["+"](4), o["-"](5)); console.log(o.p === o.p, o["+"](4), o["-"](5));
} }
expect: { expect: {
var o_p = 1, var o,
o_p = 1,
o__ = function(x) { o__ = function(x) {
return x; return x;
}, },
@@ -315,7 +318,7 @@ name_collision_4: {
} }
expect: { expect: {
console.log(function() { console.log(function() {
var o_p$0 = 0, o_q = "PASS"; var o, o_p$0 = 0, o_q = "PASS";
return function(o_p) { return function(o_p) {
if (!o_p$0) return o_p; if (!o_p$0) return o_p;
}(o_q); }(o_q);
@@ -768,7 +771,7 @@ issue_3046: {
expect: { expect: {
console.log(function(a) { console.log(function(a) {
do { do {
var b_c = a++; var b, b_c = a++;
} while (b_c && a); } while (b_c && a);
return a; return a;
}(0)); }(0));
@@ -931,7 +934,7 @@ issue_3411: {
expect: { expect: {
var c = 1; var c = 1;
!function f() { !function f() {
var o_p = --c && f(); var o, o_p = --c && f();
+{} || console.log("PASS"); +{} || console.log("PASS");
}(); }();
} }
@@ -1042,9 +1045,7 @@ issue_3945_1: {
expect: { expect: {
function f() { function f() {
o.p; o.p;
var o = { var o, o_q = 0;
q: 0,
};
} }
} }
} }
@@ -1063,9 +1064,7 @@ issue_3945_2: {
} }
expect: { expect: {
console.log(typeof o); console.log(typeof o);
var o = { var o, o_p = 0;
p: 0,
};
} }
expect_stdout: "undefined" expect_stdout: "undefined"
} }
@@ -1134,10 +1133,46 @@ issue_4985: {
}()); }());
} }
expect: { expect: {
var a_p = 42; var a, a_p = 42;
console.log(function() { console.log(function() {
({}); ({});
}()); }());
} }
expect_stdout: "undefined" expect_stdout: "undefined"
} }
issue_5182: {
options = {
hoist_props: true,
merge_vars: true,
passes: 2,
reduce_vars: true,
side_effects: true,
toplevel: true,
unused: true,
}
input: {
var o = console;
log = o.log;
o = {
p: function(a) {
console.log(a ? "PASS" : "FAIL");
return a;
},
};
log(o.p(42));
}
expect: {
var o_p = console;
log = o_p.log;
o_p = function(a) {
console.log(a ? "PASS" : "FAIL");
return a;
};
log(o_p(42));
}
expect_stdout: [
"PASS",
"42",
]
}

View File

@@ -111,7 +111,7 @@ hoist_props_const: {
} }
} }
expect: { expect: {
var o_p = "PASS"; var o = 0, o_p = "PASS";
console.log(o_p); console.log(o_p);
} }
expect_stdout: "PASS" expect_stdout: "PASS"
@@ -136,7 +136,7 @@ hoist_props_let: {
} }
expect: { expect: {
"use strict"; "use strict";
var o_p = "PASS"; var o, o_p = "PASS";
console.log(o_p); console.log(o_p);
} }
expect_stdout: "PASS" expect_stdout: "PASS"