rs6000: Add xxeval and vec_ternarylogic

rs6000: Add xxeval and vec_ternarylogic

Add the xxeval insn and access it via the vec_ternarylogic built-in
function.  As part of this, add support to the built-in function
infrastructure for functions that take four arguments.

[gcc]

2020-05-11  Kelvin Nilsen  <wschmidt@linux.ibm.com>

	* config/rs6000/altivec.h (vec_ternarylogic): New #define.
	* config/rs6000/altivec.md (UNSPEC_XXEVAL): New constant.
	(xxeval): New insn.
	* config/rs6000/predicates.md (u8bit_cint_operand): New predicate.
	* config/rs6000/rs6000-builtin.def: Add handling of new macro
	RS6000_BUILTIN_4.
	(BU_FUTURE_V_4): New macro. Use it.
	(BU_FUTURE_OVERLOAD_4): Likewise.
	* config/rs6000/rs6000-c.c (altivec_build_resolved_builtin): Add
	handling for quaternary built-in functions.
	(altivec_resolve_overloaded_builtin): Add special-case handling
	for __builtin_vec_xxeval.
	* config/rs6000/rs6000-call.c: Add handling of new macro
	RS6000_BUILTIN_4 in initialization of rs6000_builtin_info,
	bdesc0_arg, bdesc1_arg, bdesc2_arg, bdesc_3arg,
	bdesc_altivec_preds, bdesc_abs, and bdesc_htm arrays.
	(altivec_overloaded_builtins): Add definitions for
	FUTURE_BUILTIN_VEC_XXEVAL.
	(bdesc_4arg): New array.
	(htm_expand_builtin): Add handling for quaternary built-in
	functions.
	(rs6000_expand_quaternop_builtin): New function.
	(rs6000_expand_builtin): Add handling for quaternary built-in
	functions.
	(rs6000_init_builtins): Initialize builtin_mode_to_type entries
	for unsigned QImode and unsigned HImode.
	(builtin_quaternary_function_type): New function.
	(rs6000_common_init_builtins): Add handling of quaternary
	operations.
	* config/rs6000/rs6000.h (RS6000_BTC_QUATERNARY): New defined
	constant.
	(RS6000_BTC_PREDICATE): Change value of constant.
	(RS6000_BTC_ABS): Likewise.
	(rs6000_builtins): Add support for new macro RS6000_BUILTIN_4.
	* doc/extend.texi (PowerPC AltiVec Built-In Functions Available
	for a Future Architecture): Add description of vec_ternarylogic
	built-in function.

[gcc/testsuite]

2020-05-11  Kelvin Nilsen  <wschmidt@linux.ibm.com>

	* gcc.target/powerpc/vec-ternarylogic-0.c: New.
	* gcc.target/powerpc/vec-ternarylogic-1.c: New.
	* gcc.target/powerpc/vec-ternarylogic-10.c: New.
	* gcc.target/powerpc/vec-ternarylogic-2.c: New.
	* gcc.target/powerpc/vec-ternarylogic-3.c: New.
	* gcc.target/powerpc/vec-ternarylogic-4.c: New.
	* gcc.target/powerpc/vec-ternarylogic-5.c: New.
	* gcc.target/powerpc/vec-ternarylogic-6.c: New.
	* gcc.target/powerpc/vec-ternarylogic-7.c: New.
	* gcc.target/powerpc/vec-ternarylogic-8.c: New.
	* gcc.target/powerpc/vec-ternarylogic-9.c: New.