[release-branch.go1.17] cmd/compile: fix prove pass when upper condition is <= maxint
When the terminating condition is <= X, we need to make sure that
X+step doesn't overflow.
Fixes #53617
Change-Id: I36e5384d05b4d7168e48db6094200fcae409bfe5
Reviewed-on: https://go-review.googlesource.com/c/go/+/415219
Reviewed-by: Than McIntosh <thanm@google.com>
Run-TryBot: David Chase <drchase@google.com>
Reviewed-by: David Chase <drchase@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Run-TryBot: Keith Randall <khr@golang.org>
(cherry picked from commit
31b8c23c5702f129aca9241bbb2132c90b1929cc)
Reviewed-on: https://go-review.googlesource.com/c/go/+/415415
Reviewed-by: Keith Randall <khr@google.com>