[llvm-dev] TBAA

[Richard Kenner via llvm-dev]

> Are there any studies or examples of TBAA optimization for C showing
> substantive performance wins? I have not been able to find any
> papers or even compelling examples.

Consider:

void
square (float *arr, int *bound)
{
  int i;
  
  for (i = 0; i <= *bound; i++)
    arr[i] = arr[i] * arr[i];
}

without TBAA you can't hoist the reference to *bound out of the loop.  That
will prevent almost all loop optimizations.