cmd/asm, cmd/internal/obj/ppc64: add ppc64 vector registers and instructions
The current implementation for Power architecture does not include the vector
(Altivec) registers. This adds the 32 VMX registers and the most commonly used
instructions: X-form loads/stores; VX-form logical operations, add/sub,
rotate/shift, count, splat, SHA Sigma and AES cipher; VC-form compare; and
VA-form permute, shift, add/sub and select.
Fixes #15619
Change-Id: I544b990631726e8fdfcce8ecca0aeeb72faae9aa
Reviewed-on: https://go-review.googlesource.com/25600
Run-TryBot: David Chase <drchase@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org> Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com> Reviewed-by: David Chase <drchase@google.com>