Compiler Incorrect Optimization

[zhiyi]

OS: ubuntu20.04
Architecture: <x64>

./jsc bug.js

expected output
3
3

actual output
3
-1


bug.js
##################################
function f() {
    let v0 = 2147483648;
    const v1 = v0--;
    const v2 = new Float32Array([111,222,333,v1]);
    const v3 = v2.indexOf(v0);
    return v3;
}
let a0 = f();
print(a0);

for (let i = 0; i < 0x1000; i++) { f(); }
let a3 = f();
print(a3);

[Radar WebKit Bug Importer]

<rdar://problem/85449162>