[llvm] [LoopPeel] Peel to make Phis loop inductions (PR #121104)

[Madhur Amilkanthwar via llvm-commits]

madhur13490 wrote:

1. Overall, I am fine with the change. However, I feel you should assess the compile-time impact of this to be on the safe side. I suspect a negative effect on compile-time because the change will also consider Phi becoming IV.

Please refer to [compile-time-tracker.](https://llvm-compile-time-tracker.com/)

2. Can you please add a test case for the below case too?
```
#define N 100
void f(int a[], int b[]) {
  int im = N - 1;
  for (int i = 0; i < N; i++) {
    a[i] = b[i] + b[im];
    im = i;
  }
}
```



https://github.com/llvm/llvm-project/pull/121104