re PR rtl-optimization/17808 (Scheduler overly conservative in sched-deps)

	PR rtl-optimization/17808
	* sched-deps.c (sched_get_condition): Enable #if 0'ed code.
	(sched_insns_conditions_mutex_p): Split out from...
	(add_dependence): ...here.  But don't call it from here.
	(add_dependence_list): Check sched_insns_conditions_mutex_p
	before calling add_dependence.
	(add_dependence_list_and_free): Likewise.
	(fixup_sched_groups): Likewise.
	(sched_analyze_1): Likewise.
	(sched_analyze_2): Likewise (and replace a "0" with REG_DEP_TRUE).
	(sched_analyze): Likewise.
	(sched_analyze_insn): Likewise.
	* sched-ebb.c (add_deps_for_risky_insns): Likewise.
	* sched-rgn.c (add_branch_dependences): Likewise.  Also, add
	dependencies on all COND_EXEC insns to jumps ending basic blocks
	when doing intrablock scheduling.
	* sched-int.h (sched_insns_conditions_mutex_p): Add prototype.

From-SVN: r102433