Here is the patch to add the round to odd instructions using separate UNSPEC
names instead of putting the operation into the unspec.

I have done a bootstrap and check on a little endian power8 system and there
were no regressions.  Can I check this into the trunk?

[gcc]
2017-10-03  Michael Meissner  <meissner@linux.vnet.ibm.com>

	* config/rs6000/rs6000-builtin.def (BU_FLOAT128_2_HW): Define new
	helper macro for IEEE float128 hardware built-in functions.
	(SQRTF128_ODD): Add built-in functions with the round-to-odd
	semantics.
	(TRUNCF128_ODD): Likewise.
	(ADDF128_ODD): Likewise.
	(SUBF128_ODD): Likewise.
	(MULF128_ODD): Likewise.
	(DIVF128_ODD): Likewise.
	(FMAF128_ODD): Likewise.
	* config/rs6000/rs6000.md (UNSPEC_ROUND_TO_ODD): Rename to
	UNSPEC_TRUNC_ROUND_TO_ODD.
	(UNSPEC_TRUNC_ROUND_TO_ODD): Likewise.
	(UNSPEC_ADD_ROUND_TO_ODD): New unspec codes for the IEEE 128-bit
	floating point round to odd instructions.
	(UNSPEC_SUB_ROUND_TO_ODD): Likewise.
	(UNSPEC_MUL_ROUND_TO_ODD): Likewise.
	(UNSPEC_DIV_ROUND_TO_ODD): Likewise.
	(UNSPEC_FMA_ROUND_TO_ODD): Likewise.
	(UNSPEC_SQRT_ROUND_TO_ODD): Likewise.
	(trunc<mode>sf2_hw): Change the truncate with round to odd
	expansion to use UNSPEC_TRUNC_ROUND_TO_ODD.
	(add<mode>3_odd): Add insns for IEEE 128-bit floating point round
	to odd hardware instructions.
	(sub<mode>3_odd): Likewise.
	(mul<mode>3_odd): Likewise.
	(div<mode>3_odd): Likewise.
	(sqrt<mode>2_odd): Likewise.
	(fma<mode>4_odd): Likewise.
	(fms<mode>4_odd): Likewise.
	(nfma<mode>4_odd): Likewise.
	(nfms<mode>4_odd): Likewise.
	(trunc<mode>df2_odd): Change the truncate with round to odd
	expansion to use UNSPEC_TRUNC_ROUND_TO_ODD.	Add a generator
	function.
	* doc/extend.texi (PowerPC built-in functions): Update documentation
	for existing IEEE float128-bit built-in functions.  Add built-in
	functions that generate the IEEE 128-bit floating point round to
	odd instructions.

[gcc/testsuite]
2017-10-03  Michael Meissner  <meissner@linux.vnet.ibm.com>

	* gcc.target/powerpc/float128-odd.c: New test.

-- 
Michael Meissner, IBM
IBM, M/S 2506R, 550 King Street, Littleton, MA 01460-6245, USA
email: meissner@linux.vnet.ibm.com, phone: +1 (978) 899-4797