diff options
Diffstat (limited to 'lib/compress.js')
| -rw-r--r-- | lib/compress.js | 100 |
1 files changed, 58 insertions, 42 deletions
diff --git a/lib/compress.js b/lib/compress.js index c556c492..103f47f1 100644 --- a/lib/compress.js +++ b/lib/compress.js @@ -6171,6 +6171,7 @@ merge(Compressor.prototype, { if (var_decl <= 1) hoist_vars = false; } if (!hoist_funs && !hoist_vars) return; + var consts = Object.create(null); var dirs = []; var hoisted = []; var vars = new Dictionary(), vars_found = 0; @@ -6186,6 +6187,12 @@ merge(Compressor.prototype, { return make_node(AST_EmptyStatement, node); } if (hoist_vars && node instanceof AST_Var) { + if (!all(node.definitions, function(defn) { + var sym = defn.name; + return sym instanceof AST_SymbolVar + && !consts[sym.name] + && self.find_variable(sym.name) === sym.definition(); + })) return node; node.definitions.forEach(function(def) { vars.set(def.name.name, def); ++vars_found; @@ -6204,6 +6211,10 @@ merge(Compressor.prototype, { }); } if (node instanceof AST_Scope) return node; + if (node instanceof AST_SymbolConst) { + consts[node.name] = true; + return node; + } }); self.transform(tt); if (vars_found > 0) { @@ -6224,48 +6235,7 @@ merge(Compressor.prototype, { }); if (defs.length > 0) { // try to merge in assignments - for (var i = 0; i < self.body.length;) { - if (self.body[i] instanceof AST_SimpleStatement) { - var expr = self.body[i].body, sym, assign; - if (expr instanceof AST_Assign - && expr.operator == "=" - && (sym = expr.left) instanceof AST_Symbol - && vars.has(sym.name)) - { - var def = vars.get(sym.name); - if (def.value) break; - def.value = expr.right; - remove(defs, def); - defs.push(def); - self.body.splice(i, 1); - continue; - } - if (expr instanceof AST_Sequence - && (assign = expr.expressions[0]) instanceof AST_Assign - && assign.operator == "=" - && (sym = assign.left) instanceof AST_Symbol - && vars.has(sym.name)) - { - var def = vars.get(sym.name); - if (def.value) break; - def.value = assign.right; - remove(defs, def); - defs.push(def); - self.body[i].body = make_sequence(expr, expr.expressions.slice(1)); - continue; - } - } - if (self.body[i] instanceof AST_EmptyStatement) { - self.body.splice(i, 1); - continue; - } - if (self.body[i] instanceof AST_BlockStatement) { - var tmp = [ i, 1 ].concat(self.body[i].body); - self.body.splice.apply(self.body, tmp); - continue; - } - break; - } + insert_vars(self.body); defs = make_node(AST_Var, self, { definitions: defs }); @@ -6273,6 +6243,50 @@ merge(Compressor.prototype, { } } self.body = dirs.concat(hoisted, self.body); + + function insert_vars(body) { + while (body.length) { + var stat = body[0]; + if (stat instanceof AST_SimpleStatement) { + var expr = stat.body, sym, assign; + if (expr instanceof AST_Assign + && expr.operator == "=" + && (sym = expr.left) instanceof AST_Symbol + && vars.has(sym.name)) { + var def = vars.get(sym.name); + if (def.value) break; + def.value = expr.right; + remove(defs, def); + defs.push(def); + body.shift(); + continue; + } + if (expr instanceof AST_Sequence + && (assign = expr.expressions[0]) instanceof AST_Assign + && assign.operator == "=" + && (sym = assign.left) instanceof AST_Symbol + && vars.has(sym.name)) { + var def = vars.get(sym.name); + if (def.value) break; + def.value = assign.right; + remove(defs, def); + defs.push(def); + stat.body = make_sequence(expr, expr.expressions.slice(1)); + continue; + } + } + if (stat instanceof AST_EmptyStatement) { + body.shift(); + continue; + } + if (stat instanceof AST_BlockStatement && !insert_vars(stat.body)) { + body.shift(); + continue; + } + break; + } + return body.length; + } }); function scan_local_returns(fn, transform) { @@ -9352,6 +9366,8 @@ merge(Compressor.prototype, { scope.inlined = true; } while (scope = scope.parent_scope); } + } else if (fixed.name && fixed.name.name == "await" && is_async(fixed)) { + single_use = false; } if (single_use) fixed.parent_scope = self.scope; } else if (!fixed || !fixed.is_constant_expression()) { |