Per golang.org/s/generatedcode

Updates #nnn

Change-Id: Ia7513ef6bd26c20b62b57b29f7770684a315d389
Reviewed-on: https://go-review.googlesource.com/45470
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
Reviewed-by: Matt Layher <mdlayher@gmail.com>
Reviewed-by: Ian Lance Taylor <iant@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>

Replace the confusing game where a frame size of $-8 would suppress the
implicit setting up of a stack frame with a nice explicit flag.

The code to set up the function prologue is still a little confusing but better
than it was.

Change-Id: I1d49278ff42c6bc734ebfb079998b32bc53f8d9a
Reviewed-on: https://go-review.googlesource.com/15670
Reviewed-by: Minux Ma <minux@golang.org>

All of the architectures except ppc64 have only "RET" for the return
mnemonic. ppc64 used to have only "RETURN", but commit cf06ea6
introduced RET as a synonym for RETURN to make ppc64 consistent with
the other architectures. However, that commit was never followed up to
make the code itself consistent by eliminating uses of RETURN.

This commit replaces all uses of RETURN in the ppc64 assembly with
RET.

This was done with
    sed -i 's/\<RETURN\>/RET/' **/*_ppc64x.s
plus one manual change to syscall/asm.s.

Change-Id: I3f6c8d2be157df8841d48de988ee43f3e3087995
Reviewed-on: https://go-review.googlesource.com/10672
Reviewed-by: Rob Pike <r@golang.org>
Reviewed-by: Russ Cox <rsc@golang.org>
Reviewed-by: Minux Ma <minux@golang.org>

This makes it easier to experiment with alternative implementations.

While we're here, update the comments.

No functional changes. Passes toolstash -cmp.

Change-Id: I428535754908f0fdd7cc36c214ddb6e1e60f376e
Reviewed-on: https://go-review.googlesource.com/8310
Reviewed-by: Keith Randall <khr@golang.org>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>