[ARC] Add single/double IEEE precission FPU support.

[ARC] Add single/double IEEE precission FPU support.

gcc/
2016-02-16  Claudiu Zissulescu  <claziss@synopsys.com>

	* config/arc/arc-modes.def (CC_FPU, CC_FPU_UNEQ): New modes.
	* config/arc/arc-opts.h (FPU_SP, FPU_SF, FPU_SC, FPU_SD, FPU_DP)
	(FPU_DF, FPU_DC, FPU_DD, FXP_DP): Define.
	* config/arc/arc.c (arc_init): Check FPU options.
	(get_arc_condition_code): Handle new CC_FPU* modes.
	(arc_select_cc_mode): Likewise.
	(arc_conditional_register_usage): Allow 64 bit datum into even-odd
	register pair only. Allow access for ARCv2 accumulator.
	(gen_compare_reg): Whenever we have FPU support use FPU compare
	instructions.
	(arc_reorg): Don't generate brcc insns when FPU compare
	instructions are involved.
	* config/arc/arc.h (TARGET_DPFP): Add TARGET_FP_DPAX condition.
	(TARGET_OPTFPE): Add condition when ARC EM can use optimized
	floating point emulation.
	(ACC_REG_FIRST, ACC_REG_LAST, ACCL_REGNO, ACCH_REGNO): Define.
	(REVERSE_CONDITION): Add new CC_FPU* modes.
	(TARGET_FP_SP_BASE): Define.
	(TARGET_FP_DP_BASE): Likewise.
	(TARGET_FP_SP_FUSED): Likewise.
	(TARGET_FP_DP_FUSED): Likewise.
	(TARGET_FP_SP_CONV): Likewise.
	(TARGET_FP_DP_CONV): Likewise.
	(TARGET_FP_SP_SQRT): Likewise.
	(TARGET_FP_DP_SQRT): Likewise.
	(TARGET_FP_DP_AX): Likewise.
	* config/arc/arc.md (ARCV2_ACC): New constant.
	(type): New fpu type attribute.
	(SDF): Conditional iterator.
	(cstore<mode>, cbranch<mode>): Change expand condition.
	(addsf3, subsf3, mulsf3, adddf3, subdf3, muldf3): New expands,
	handles FPU/FPX cases as well.
	* config/arc/arc.opt (mfpu): New option.
	* config/arc/fpx.md (addsf3_fpx, subsf3_fpx, mulsf3_fpx):
	Renamed.
	(adddf3, muldf3, subdf3): Removed.
	* config/arc/predicates.md (proper_comparison_operator): Recognize
	CC_FPU* modes.
	* config/arc/fpu.md: New file.
	* doc/invoke.texi (ARC Options): Document mfpu option.

From-SVN: r233451