S/390: PR80080: Optimize atomic patterns.

S/390: PR80080: Optimize atomic patterns.

The attached patch optimizes the atomic_exchange and atomic_compare
patterns on s390 and s390x (mostly limited to SImode and DImode).
Among general optimizaation, the changes fix most of the problems
reported in PR 80080:
https://gcc.gnu.org/bugzilla/show_bug.cgi?id=80080

gcc/ChangeLog:

2017-04-25  Dominik Vogt  <vogt@linux.vnet.ibm.com>

	PR target/80080
	* s390-protos.h (s390_expand_cs_hqi): Removed.
	(s390_expand_cs, s390_expand_atomic_exchange_tdsi): New prototypes.
	* config/s390/s390.c (s390_emit_compare_and_swap): Handle all integer
	modes as well as CCZ1mode and CCZmode.
	(s390_expand_atomic_exchange_tdsi, s390_expand_atomic): Adapt to new
	signature of s390_emit_compare_and_swap.
	(s390_expand_cs_hqi): Likewise, make static.
	(s390_expand_cs_tdsi): Generate an explicit compare before trying
	compare-and-swap, in some cases.
	(s390_expand_cs): Wrapper function.
	(s390_expand_atomic_exchange_tdsi): New backend specific expander for
	atomic_exchange.
	(s390_match_ccmode_set): Allow CCZmode <-> CCZ1 mode.
	* config/s390/s390.md ("atomic_compare_and_swap<mode>"): Merge the
	patterns for small and large integers.  Forbid symref memory operands.
	Move expander to s390.c.  Require cc register.
	("atomic_compare_and_swap<DGPR:mode><CCZZ1:mode>_internal")
	("*atomic_compare_and_swap<TDI:mode><CCZZ1:mode>_1")
	("*atomic_compare_and_swapdi<CCZZ1:mode>_2")
	("*atomic_compare_and_swapsi<CCZZ1:mode>_3"): Use s_operand to forbid
	symref memory operands.  Remove CC mode and call s390_match_ccmode
	instead.
	("atomic_exchange<mode>"): Allow and implement all integer modes.

gcc/testsuite/ChangeLog:

2017-04-25  Dominik Vogt  <vogt@linux.vnet.ibm.com>

	PR target/80080
	* gcc.target/s390/md/atomic_compare_exchange-1.c: New test.
	* gcc.target/s390/md/atomic_compare_exchange-1.inc: New test.
	* gcc.target/s390/md/atomic_exchange-1.inc: New test.

From-SVN: r247132