prevent REG_EQUAL on set-mem insns

[Eric Botcazou]

> 2010-09-10  Olivier Hainque  <hainque@adacore.com>
>
>         * fwprop.c (forward_propagate_and_simplify): Only attach a
> 	REG_EQUAL note to an insn if the destination is a register.
>         * gcse.c (try_replace_reg): Likewise.
>
> 	testsuite/
> 	* gnat.dg/memtrap.adb: New test.

Something strange apparently happened to your testcase in the commit.

-- 
Eric Botcazou