[Patch] Fix PR44328 - switch/case optimization produces an invalid lookup table index

[Ian Bolton]

H.J.Lu writes:
> >        * testsuite/gcc.target/arm/pr44328.C: New test.
> >
> 
> Why is this test ARM specific?

It's because I didn't know the right place to put it yet. ;-)

I am open to suggestions as to where it should go, and what
options to give it.

For trunk, I need "-fstrict-enums -O2 -Wextra" to cause the
circumstances that exposed the bug, and check that there are
no warnings.  For 4.5 branch, -fstrict-enums does not exist,
so I guess I only want "-O2 -Wextra".

Cheers,
Ian