This package defines a control-flow graph of Go statements and
expressions. It was originally built as part of cmd/vet (where
it was in turn derived from x/tools/go/ssa) and is being
published to make it available to other analyses.
Change-Id: Ib6077c5a856bb74d6a8411e9c3f9e2f79beb5658
Reviewed-on: https://go-review.googlesource.com/135636
Reviewed-by: Ian Cottrell <iancottrell@google.com>