Bug 280144 – Deleting existing entry from Map/Set followed by re-adding is 30x slower than in v8

• Status: RESOLVED
• Resolution: DUPLICATE
• Component: JavaScriptCore

[Dylan Conway]

Example minified from https://github.com/oven-sh/bun/issues/14063

```
var map = new Set();

for (var i = 0; i < 1000; i++) {
    for (var j = 0; j < 1000; j++) {
        map.delete(j);
        map.add(j);
    }
}
```

Running this on an m1 max takes about 1 second with JSC. With v8 it takes about 100 milliseconds.

Switching the order of `delete` and `add`, or combining the loops into a single loop to 1000000 does not seem to repro this behavior.

[Dylan Conway]

I suspect this is a bug causing the table to resize too frequently. Removing `shrinkIfNeeded` in `OrderedHashTableHelper::removeImpl` almost brings performance back to normal

[Radar WebKit Bug Importer]

<rdar://problem/136912759>

[Yusuke Suzuki]

Thanks. Oops, I accidentally opened a new bugzilla for patch upload. Merging it to that as it already has GitHub link.

*** This bug has been marked as a duplicate of bug 280600 ***