[dev.unified] cmd/compile: make Unified IR always writes concrete type for const exprs
So we don't have to depend on typecheck pass to fixup the concrete
type for some constant expressions. Previously, the problem won't show up,
until CL 418475 sent, which removes an un-necessary type conversion in
"append(a, b...) to help the optimization kicks in.
For #53888
Change-Id: Idaecd38b7abbaa3ad5b00ff3b1fb0fd8bbeb6726
Reviewed-on: https://go-review.googlesource.com/c/go/+/418514
Run-TryBot: Cuong Manh Le <cuong.manhle.vn@gmail.com> Reviewed-by: Matthew Dempsky <mdempsky@google.com> Reviewed-by: Dmitri Shuralyov <dmitshur@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>