rs6000: Add vec_extracth and vec_extractl

rs6000: Add vec_extracth and vec_extractl

Add new insns vextdu[bhw]vlx, vextddvlx, vextdu[bhw]vhx, and
vextddvhx, along with built-in access and overloaded built-in
access to these insns.

[gcc]

2020-05-13  Kelvin Nilsen  <kelvin@gcc.gnu.org>

	* config/rs6000/altivec.h (vec_extractl): New #define.
	(vec_extracth): Likewise.
	* config/rs6000/altivec.md (UNSPEC_EXTRACTL): New constant.
	(UNSPEC_EXTRACTR): Likewise.
	(vextractl<mode>): New expansion.
	(vextractl<mode>_internal): New insn.
	(vextractr<mode>): New expansion.
	(vextractr<mode>_internal): New insn.
	* config/rs6000/rs6000-builtin.def (__builtin_altivec_vextdubvlx):
	New built-in function.
	(__builtin_altivec_vextduhvlx): Likewise.
	(__builtin_altivec_vextduwvlx): Likewise.
	(__builtin_altivec_vextddvlx): Likewise.
	(__builtin_altivec_vextdubvhx): Likewise.
	(__builtin_altivec_vextduhvhx): Likewise.
	(__builtin_altivec_vextduwvhx): Likewise.
	(__builtin_altivec_vextddvhx): Likewise.
	(__builtin_vec_extractl): New overloaded built-in function.
	(__builtin_vec_extracth): Likewise.
	* config/rs6000/rs6000-call.c (altivec_overloaded_builtins):
	Define overloaded forms of __builtin_vec_extractl and
	__builtin_vec_extracth.
	(builtin_function_type): Add cases to mark arguments of new
	built-in functions as unsigned.
	(rs6000_common_init_builtins): Add
	opaque_ftype_opaque_opaque_opaque_opaque.
	* config/rs6000/rs6000.md (du_or_d): New mode attribute.
	* doc/extend.texi (PowerPC AltiVec Built-in Functions Available
	for a Future Architecture): Add description of vec_extractl and
	vec_extractr built-in functions.

[gcc/testsuite]

2020-05-13  Kelvin Nilsen  <kelvin@gcc.gnu.org>

	* gcc.target/powerpc/vec-extracth-0.c: New.
	* gcc.target/powerpc/vec-extracth-1.c: New.
	* gcc.target/powerpc/vec-extracth-2.c: New.
	* gcc.target/powerpc/vec-extracth-3.c: New.
	* gcc.target/powerpc/vec-extracth-4.c: New.
	* gcc.target/powerpc/vec-extracth-5.c: New.
	* gcc.target/powerpc/vec-extracth-6.c: New.
	* gcc.target/powerpc/vec-extracth-7.c: New.
	* gcc.target/powerpc/vec-extracth-be-0.c: New.
	* gcc.target/powerpc/vec-extracth-be-1.c: New.
	* gcc.target/powerpc/vec-extracth-be-2.c: New.
	* gcc.target/powerpc/vec-extracth-be-3.c: New.
	* gcc.target/powerpc/vec-extractl-0.c: New.
	* gcc.target/powerpc/vec-extractl-1.c: New.
	* gcc.target/powerpc/vec-extractl-2.c: New.
	* gcc.target/powerpc/vec-extractl-3.c: New.
	* gcc.target/powerpc/vec-extractl-4.c: New.
	* gcc.target/powerpc/vec-extractl-5.c: New.
	* gcc.target/powerpc/vec-extractl-6.c: New.
	* gcc.target/powerpc/vec-extractl-7.c: New.
	* gcc.target/powerpc/vec-extractl-be-0.c: New.
	* gcc.target/powerpc/vec-extractl-be-1.c: New.
	* gcc.target/powerpc/vec-extractl-be-2.c: New.
	* gcc.target/powerpc/vec-extractl-be-3.c: New.