This patch changes the inliner to use callsite scores when deciding to
inline as opposed to looking only at callee cost/hairyness.
For this to work, we have to relax the inline budget cutoff as part of
CanInline to allow for the possibility that a given function might
start off with a cost of N where N > 80, but then be called from a
callsites whose score is less than 80. Once a given function F in
package P has been approved by CanInline (based on the relaxed budget)
it will then be emitted as part of the export data, meaning that other
packages importing P will need to also need to compute callsite scores
appropriately.
For a function F that calls function G, if G is marked as potentially
inlinable then the hairyness computation for F will use G's cost for
the call to G as opposed to the default call cost; for this to work
with the new scheme (given relaxed cost change described above) we
use G's cost only if it falls below inlineExtraCallCost, otherwise
just use inlineExtraCallCost.
Included in this patch are a bunch of skips and workarounds to
selected 'errorcheck' tests in the <GOROOT>/test directory to deal
with the additional "can inline" messages emitted when the new inliner
is turned on.
Change-Id: I9be5f8cd0cd8676beb4296faf80d2f6be7246335
Reviewed-on: https://go-review.googlesource.com/c/go/+/519197
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Added a flag '-d=inlfuncswithclosures=1' to allow inlining functions with
closures, and change the default to off for now, until #44370 is fixed.
Updates #44370.
Change-Id: Ic17723aa5c091d91f5f5004d8b63ec7125257acf
Reviewed-on: https://go-review.googlesource.com/c/go/+/296049
Run-TryBot: Dan Scales <danscales@google.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
TryBot-Result: Go Bot <gobot@golang.org>
Trust: Dan Scales <danscales@google.com>
CL 65071 enabled inlining for local closures with no captures.
To determine safety of inlining a call sites, we check whether the
variable holding the closure has any assignments after its original
definition.
Unfortunately, that check did not catch OAS2MAPR and OAS2DOTTYPE,
leading to incorrect inlining when a variable holding a closure was
subsequently reassigned through a type conversion or a 2-valued map
access.
There was another more subtle issue wherein reassignment check would
always return a false positive for closure calls inside other
closures. This was caused by the Name.Curfn field of local variables
pointing to the OCLOSURE node instead of the corresponding ODCLFUNC,
which resulted in reassigned walking an empty Nbody and thus never
seeing any reassignments.
This CL fixes these oversights and adds many more tests for closure
inlining which ensure not only that inlining triggers but also the
correctness of the resulting code.
Updates #15561
Change-Id: I74bdae849c4ecfa328546d6d62b512e8d54d04ce
Reviewed-on: https://go-review.googlesource.com/75770
Reviewed-by: Hugues Bruant <hugues.bruant@gmail.com>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
Run-TryBot: Brad Fitzpatrick <bradfitz@golang.org>
TryBot-Result: Gobot Gobot <gobot@golang.org>