constraints.md (ZQ, ZR, ZS, ZT): New constraints.

constraints.md (ZQ, ZR, ZS, ZT): New constraints.

2009-07-22  Andreas Krebbel  <krebbel1@de.ibm.com>

	* config/s390/constraints.md (ZQ, ZR, ZS, ZT): New constraints.
	(U, W): Constraints are now deprecated and will be removed if we
	run out of letters.
	* config/s390/s390.md (U, W): Replaced with ZQZR, ZSZT throughout
	the file.
	("prefetch"): Add the stcmh instruction for prefetching.
	* config/s390/s390.c (s390_symref_operand_p): Function moved. No
	changes.
	(s390_short_displacement): Return always true if compiling for
	machines not providing the long displacement facility.
	(s390_mem_constraint): Support the new constraint letter Z.
	(s390_check_qrst_address): New function.

From-SVN: r149917