cmd/compile: detect invalid NIH conversions within unified IR
Unified IR currently relies on typecheck to diagnose invalid
//go:notinheap conversions, which prevents removing all of
its (otherwise) dead error-reporting code.
This CL updates the unified IR reader to instead proactively diagnose
these invalid conversions. This logic can be removed again once #46731
is implemented, but in the mean time it allows progress on #51691.
Updates #46731.
Updates #51691.
Change-Id: Ifae81aaad770209ec7a67bc10b55660f291e403e
Reviewed-on: https://go-review.googlesource.com/c/go/+/392917
Trust: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org> Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>