cmd/compile: make stkobj symbols content-addressable
Shrinks binaries a little bit.
size before after Δ %
api
4892370 4875858 -16512 -0.338%
asm
4711218 4694706 -16512 -0.350%
cgo
4164770 4148258 -16512 -0.396%
compile
21875922 21826386 -49536 -0.226%
cover
4358370 4341858 -16512 -0.379%
doc
3532562 3516050 -16512 -0.467%
link
6110786 6094274 -16512 -0.270%
objdump
3982914 3966402 -16512 -0.415%
pprof
12869986 12836962 -33024 -0.257%
trace
9614626 9598114 -16512 -0.172%
vet
6580322 6563810 -16512 -0.251%
total
102897284 102666116 -231168 -0.225%
Change-Id: Idf4ba3c05e35ec1d1ae957d6ded00ae79cc0fd2a
Reviewed-on: https://go-review.googlesource.com/c/go/+/172198
Trust: Josh Bleecher Snyder <josharian@gmail.com>
Run-TryBot: Josh Bleecher Snyder <josharian@gmail.com>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Cherry Mui <cherryyz@google.com>