This patch makes use of ppc64 VMX instructions to accelerate AES
computation. There is a speed boost of over 5 times using these
instructions.

			old ns/op	new ns/op	delta
BenchmarkEncrypt-96	167		33.4		-80%
BenchmarkDecrypt-96	173		32.7		-81.1%
BenchmarkExpand-96	962		140		-85.45

			old MB/s	new MB/s	speedup
BenchmarkEncrypt-96	95.62		479.49		5.01x
BenchmarkDecrypt-96	92.61		489.98		5.29x

Fixes golang#18499

This patch makes use of ppc64 VMX instructions to accelerate AES
computation. There is a speed boost of over 5 times using these
instructions.

			old ns/op	new ns/op	delta
BenchmarkEncrypt-96	167		33.4		-80%
BenchmarkDecrypt-96	173		32.7		-81.1%
BenchmarkExpand-96	962		140		-85.45

			old MB/s	new MB/s	speedup
BenchmarkEncrypt-96	95.62		479.49		5.01x
BenchmarkDecrypt-96	92.61		489.98		5.29x

Updates golang#18499

This does not enable GCM or CBC variants for ppc64, they
require more work to support bi-endian.

Updates #18499

Change-Id: Ic2bbe81c60107abc0a4803d8b9a833213286b1d0
Reviewed-on: https://go-review.googlesource.com/c/go/+/404395
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Paul Murphy <murp@ibm.com>
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>
Reviewed-by: Filippo Valsorda <valsorda@google.com>

This adds the code to allow the gcm assembler code to work on
big endian ppc64.

Updates #18499

Change-Id: Iab1ffc9b8af38a0605a91f2621dd9f4a9397b945
Reviewed-on: https://go-review.googlesource.com/c/go/+/404795
Reviewed-by: Heschi Kreinick <heschi@google.com>
Reviewed-by: Paul Murphy <murp@ibm.com>
Run-TryBot: Lynn Boger <laboger@linux.vnet.ibm.com>
Reviewed-by: David Chase <drchase@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>

This reworks how we load/store vector registers using the new
bi-endian P9 instruction emulation macros. This also removes
quite a bit of asm used to align and reorder vector registers.

This is also a slight improvement on P9 ppc64le/linux:

    name             old speed      new speed      delta
    AESCBCEncrypt1K   936MB/s ± 0%   943MB/s ± 0%  +0.80%
    AESCBCDecrypt1K  1.28GB/s ± 0%  1.37GB/s ± 0%  +6.76%

Updates #18499

Change-Id: Ic5ff71d217d7302b6ae4e8d877c25004bfda5ecd
Reviewed-on: https://go-review.googlesource.com/c/go/+/405134
Run-TryBot: Paul Murphy <murp@ibm.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
Reviewed-by: Lynn Boger <laboger@linux.vnet.ibm.com>
Reviewed-by: Ian Lance Taylor <iant@google.com>