add movq

This does the equivalent of dst = *(src + off),
which we use to find our gather base pointer in gather32.

Change-Id: I09ca7bfd404d7dce6de454ef1ed4eee78ab29932
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/264216
Commit-Queue: Mike Klein <mtklein@google.com>
Reviewed-by: Herb Derby <herb@google.com>
3 files changed