compare-elim.c (conforming_compare): Accept UNSPECs.

compare-elim.c (conforming_compare): Accept UNSPECs.

	* compare-elim.c (conforming_compare): Accept UNSPECs.
	(find_comparison_dom_walker::before_dom_children): Deal with
	instructions both using and killing the flags register.
	(equivalent_reg_at_start): New function extracted from...
	(try_eliminate_compare): ...here.  Use it and add support for
	registers and UNSPECs as second operand of the compare.
	* config/visium/visium-modes.def (CCV): New.
	* config/visium/predicates.md (visium_v_comparison_operator): New.
	(visium_branch_operator): Deal with CCV mode.
	* config/visium/visium.c (visium_select_cc_mode): Likewise.
	(output_cbranch): Likewise.
	* config/visium/visium.md (UNSPEC_{ADD,SUB,NEG}V): New constants.
	(uaddv<mode>4): New expander.
	(addv<mode>4): Likewise.
	(add<mode>3_insn_set_carry): New instruction.
	(add<mode>3_insn_set_overflow): Likewise.
	(addsi3_insn_set_overflow): Likewise.
	(usubv<mode>4): New expander.
	(subv<mode>4): Likewise.
	(sub<mode>3_insn_set_carry): New instruction.
	(sub<mode>3_insn_set_overflow): Likewise.
	(subsi3_insn_set_overflow): Likewise.
	(unegv<mode>3): New expander.
	(negv<mode>3): Likewise.
	(neg<mode>2_insn_set_overflow): New instruction.
	(addv_tst<mode>): Likewise.
	(subv_tst<mode>): Likewise.
	(negv_tst<mode>): Likewise.
	(cbranch<mode>4_addv_insn): New splitter and instruction.
	(cbranch<mode>4_subv_insn): Likewise.
	(cbranch<mode>4_negv_insn): Likewise.

From-SVN: r241379