possible gcse failure: not able to eliminate redundant loads

[Richard Henderson]

On Fri, Dec 13, 2002 at 11:26:34AM +0530, Sanjiv Kumar Gupta, Noida wrote:
>         b[2] = a[1];
>         for (j = 0; j < i; j++)
>         {
>                if (i)
>                    b[3] = a[1];

Yes, this requires more knowledge than is present in loop.

Ignoring the first statement, we cannot hoist a[1] because
it is only conditionally executed and might trap.  But we
don't have any code that knows how to propagate the fact
that we've already loaded from a earlier.

This case needs some form of gcse to work.


r~