Intermediate writes to array slot not eliminated by optimizer

[Vitaly Davidovich]

Anyone? :)

Thanks

On Mon, May 11, 2015 at 8:25 PM, Vitaly Davidovich <vitalyd at gmail.com>
wrote:

> Hi guys,
>
> Suppose we have the following code:
>
> private static final long[] ARR = new long[10];
> private static final int ITERATIONS = 500 * 1000 * 1000;
>
>
> static void loop() {
>     int i = ITERATIONS;
>     while(--i >= 0) {
>          ARR[4] = i;
>      }
> }
>
> My expectation would be that loop() effectively compiles to:
> ARR[4] = 0;
> ret;
>
> However, an actual loop is compiled.  This example is a reduction of a
> slightly more involved case that I had in mind, but I'm curious if I'm
> missing something here.
>
> I tested this with 8u40 and tiered compilation disabled, for what it's
> worth.
>
> Thanks
>
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