reg-stack.c (subst_stack_regs_pat): Handle <UNSPEC_FIST> case.

	* reg-stack.c (subst_stack_regs_pat): Handle <UNSPEC_FIST> case.
	* config/i386/i386.c (output_fix_trunc): Add new round_mode
	variable.  Output "fldcw" depending on round_mode.
	* config/i386/i386.md (UNSPEC_FIST): New.
	(fistdi2, fistdi2_with_temp, fist<mode>2, fist<mode>2_with_temp):
	New isns patterns to implement lrint and llrint built-ins as x87
	intrinsic function.
	(fistdi2, fist<mode>2 splitters): New splitters.
	(lrint<mode>2): New expanders.

From-SVN: r97151