This change reduces the sizes of the critical section
in traces.ProcessEvent, in particular moving allocations
ahead of Lock. This reduces the contention according
to the trace profiler.
See https://go-review.googlesource.com/c/go/+/411909 for
another reduction in contention. The largest remaining
contention is Handle.Get, which thousands of goroutines
wait for because we initiate typechecking top down.
(Second attempt at https://go-review.googlesource.com/c/tools/+/411910,
reverted in https://go-review.googlesource.com/c/tools/+/412694.
The changes to Generation.Bind have been dropped.)
Change-Id: Ia9050c97bd12d2d75055f8d1dfcda3ef1f5ad334
Reviewed-on: https://go-review.googlesource.com/c/tools/+/412820
Run-TryBot: Alan Donovan <adonovan@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
gopls-CI: kokoro <noreply+kokoro@google.com>
Reviewed-by: Hyang-Ah Hana Kim <hyangah@gmail.com>