[PATCH][compare-elim] Fix PR rtl-optimization/82597

[Michael Collison]

This patch fixes an ICE on x86 because we were not constraining the operands
of a recognized insn. Bootstrapped and tested on aarch64-none-linux-gnu and 
x86_64.

Also successfully compiled the failing test cases in 82597 and duplicate 82592.

Ok for trunk?

2017-10-18  Michael Collison  <michael.colli...@arm.com>

        PR rtl-optimization/82597
        * compare-elim.c: (try_validate_parallel): Constrain operands
        of recognized insn.

2017-10-18  Michael Collison  <michael.colli...@arm.com>
        * gcc.dg/pr82597.c: New test.

rb8338.patch
Description: rb8338.patch