[dev.regabi] cmd/compile: change iexport to avoid map[ir.Node]
In the past, we had a lot of trouble with misusing *types.Sym
throughout the frontend, so I tried to push us towards always passing
around ONAMEs instead. But for constructing and writing out the symbol
indexes for the indexed export data, keying by *types.Sym is exactly
what we want.
Passes buildall w/ toolstash -cmp.
Updates #42982.
Change-Id: Idd8f1fb057d75a52a34ebc7788d9332fb49caf8d
Reviewed-on: https://go-review.googlesource.com/c/go/+/275755
Trust: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Go Bot <gobot@golang.org> Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>