Bug 205573 – JSC::WatchpointSet* JSC::Structure::ensurePropertyReplacementWatchpointSet ASSERTION FAILED

• Status: NEW
• Component: JavaScriptCore

When jsc run code below ,it will throw an ASSERTION FAILED in function 
JSC::WatchpointSet* JSC::Structure::ensurePropertyReplacementWatchpointSet

```
//poc
function main() {
const v1 = {length:parseInt};
let v3 = v1;
for (let v6 = 0; v6 < 100; v6 = v6 + 2.0) {
    function v8(v9,v10,v11,v12) {
        try {
            const v13 = v9();
            const v15 = {get:v13};
            const v17 = Object.defineProperty(v13,"c",v15);
            v3.__proto__ = v13;
            const v18 = v1.arguments;
        } catch(v19) {
        }
        return v8;
    }
    const v21 = [293729.1679360643,2635518607,293729.1679360643,293729.1679360643,293729.1679360643];
    const v22 = v21.reduce(v8);
}
}
noDFG(main);
noFTL(main);
main();
```

the command line I used

```
jsc --validateOptions=true --useConcurrentJIT=false --thresholdForJITSoon=10 --thresholdForJITAfterWarmUp=10 --thresholdForOptimizeAfterWarmUp=100 --thresholdForOptimizeAfterLongWarmUp=100 --thresholdForOptimizeAfterLongWarmUp=100 --thresholdForFTLOptimizeAfterWarmUp=1000 --thresholdForFTLOptimizeSoon=1000 --gcAtEnd=true '/home/android/Desktop/JSC_Crash/crash_1576593415940_20540_deterministic_6.js
```

and the result I get

```
ASSERTION FAILED: !isUncacheableDictionary()
../../Source/JavaScriptCore/runtime/Structure.cpp(847) : JSC::WatchpointSet* JSC::Structure::ensurePropertyReplacementWatchpointSet(JSC::VM&, JSC::PropertyOffset)
Aborted (core dumped)
```

[Radar WebKit Bug Importer]

<rdar://problem/58186007>