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1dec296000
Summary:
Uglify@3.1.7 is causing some perf issues (more specifically, this commit: 5b4b07e9a7) that are impacting TTI on RN views and increased memory usage.
More specifically, code like:
```
function nonTrivialFn(pre) {
return pre + Math.random();
}
function hotFunctionCalledALotOfTimes(num) {
return nonTrivialFn(num + Math.random());
}
hotFunctionCalledALotOfTimes(3);
hotFunctionCalledALotOfTimes(5);
```
in v3.1.7 gets converted to:
```
function hotFunctionCalledALotOfTimes(num){
return function(pre) {
return pre + Math.random();
}(num + Math.random())
}
hotFunctionCalledALotOfTimes(3);
hotFunctionCalledALotOfTimes(5);
```
This causes a function creation each time `hotFunctionCalledALotOfTimes` is called.
By comparison, in v3.1.6, that previous code was converted to:
```
function nonTrivialFn(pre){
return pre + Math.random()
}
function hotFunctionCalledALotOfTimes(num){
return nonTrivialFn(num + Math.random())
}
hotFunctionCalledALotOfTimes(3);
hotFunctionCalledALotOfTimes(5);
```
Reviewed By: jeanlauliac, alexeylang
Differential Revision: D6296740
fbshipit-source-id: b3988d886e607103ec3ae6b9763b2f0411a8aa3c