From d98b7bf2f7e18b37860a29e34edaf2928555a42e Mon Sep 17 00:00:00 2001 From: alexlamsl Date: Sat, 14 Apr 2018 14:49:35 +0800 Subject: [PATCH] improve performance when handling unused variables in `collapse_vars` fixes #3082 --- lib/compress.js | 3 ++- 1 file changed, 2 insertions(+), 1 deletion(-) diff --git a/lib/compress.js b/lib/compress.js index 999e03c4..f82d99ef 100644 --- a/lib/compress.js +++ b/lib/compress.js @@ -1348,8 +1348,9 @@ merge(Compressor.prototype, { if (expr instanceof AST_VarDef) { var def = expr.name.definition(); if (!member(expr.name, def.orig)) return; - var declared = def.orig.length - def.eliminated; var referenced = def.references.length - def.replaced; + if (!referenced) return; + var declared = def.orig.length - def.eliminated; if (declared > 1 && !(expr.name instanceof AST_SymbolFunarg) || (referenced > 1 ? mangleable_var(expr) : !compressor.exposed(def))) { return make_node(AST_SymbolRef, expr.name, expr.name);