Hello!

Attached patch fixes runtime comparison failure of 454.calculix due to
wrong movement of vzeroupper in jump2 pass. It turns out, that
can_move_insns_accross function does not special-case
unspec_volatiles, so vzeroupper is allowed to pass various 256bit avx
instructions.

The patch rejects moves of unspec_volatile insns in can_move_insn_accross.

2012-01-06  Uros Bizjak  <ubizjak@gmail.com>

	PR rtl-optimization/55845
	* df-problems.c (can_move_insns_across): Stop scanning at
	unspec_volatile source instruction.

2012-01-06  Uros Bizjak  <ubizjak@gmail.com>
	    Vladimir Yakovlev  <vladimir.b.yakovlev@intel.com>

	PR rtl-optimization/55845
	* gcc.target/i386/pr55845.c: New test.

Bootstrapped and regression tested on x86_64-pc-linux-gnu {,-m32} AVX target.

OK for mainline and 4.7 branch?

Uros.