The code that analyzes function return values checks for cases where a
function F always returns the same inlinable function, e.g.
func returnsFunc() func(*int, int) { return setit }
func setit(p *int, v int) { *p = v }
The check for inlinability was being done by looking at "fn.Inl !=
nil", which is probably not what we want, since it includes functions
whose cost value is between 80 and 160 and may only be inlined if lots
of other heuristics kick in.
This patch changes the "always returns same inlinable func" heuristic
to ensure that the func in question has a size of 80 or less, so as to
restrict this case to functions that have a high likelihood of being
inlined.
Change-Id: I06003bca1c56c401df8fd51c922a59c61aa86bea
Reviewed-on: https://go-review.googlesource.com/c/go/+/529116
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com> Reviewed-by: Matthew Dempsky <mdempsky@google.com>