It makes use of the hiter structure which matches runtime.hiter's.
This change mainly improves the performance of Next method of MapIter.
goos: darwin
goarch: arm64
pkg: reflect
cpu: Apple M2
│ ./old.txt │ ./new.txt │
│ sec/op │ sec/op vs base │
MapIterNext-8 61.95n ± 0% 54.95n ± 0% -11.28% (p=0.000 n=10)
for the change of `test/escape_reflect.go`:
removing mapiterkey, mapiterelem would cause leaking MapIter content
when calling SetIterKey and SetIterValue,
and this may cause map bucket to be allocated on heap instead of stack.
Reproduce:
```
{
m := map[int]int{1: 2} // escapes to heap after this change
it := reflect.ValueOf(m).MapRange()
it.Next()
var k, v int
reflect.ValueOf(&k).Elem().SetIterKey(it)
reflect.ValueOf(&v).Elem().SetIterValue(it)
println(k, v)
}
```
This CL would not introduce abi.NoEscape to fix this. It may need futher
optimization and tests on hiter field usage and its escape analysis.
Fixes#69416
Change-Id: Ibaa33bcf86228070b4a505b9512680791aa59f04
Reviewed-on: https://go-review.googlesource.com/c/go/+/612616
Reviewed-by: Keith Randall <khr@golang.org>
Auto-Submit: Keith Randall <khr@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Reviewed-by: Keith Randall <khr@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
One of the more tedious quirks of the original frontend (i.e.,
typecheck) to preserve was that it preserved the original
representation of constants into the backend. To fit into the unified
IR model, I ended up implementing a fairly heavyweight workaround:
simply record the original constant's string expression in the export
data, so that diagnostics could still report it back, and match the
old test expectations.
But now that there's just a single frontend to support, it's easy
enough to just update the test expectations and drop this support for
"raw" constant expressions.
Change-Id: I1d859c5109d679879d937a2b213e777fbddf4f2f
Reviewed-on: https://go-review.googlesource.com/c/go/+/526376
Reviewed-by: Keith Randall <khr@golang.org>
Reviewed-by: Keith Randall <khr@google.com>
LUCI-TryBot-Result: Go LUCI <golang-scoped@luci-project-accounts.iam.gserviceaccount.com>
Auto-Submit: Matthew Dempsky <mdempsky@google.com>
Reviewed-by: Cuong Manh Le <cuong.manhle.vn@gmail.com>
With CL 408826 reflect.Value does not always escape. We need to
make sure Value operations does (or does not) escape the Value
correctly. This CL adds a test.
There are still a few unfortunate cases, where some Value
operations escape more than necessary (comparing to a non-reflect
version of the code), but hard to fix. These are mostly that a
Value would escape conditionally (mostly on the type of the Value),
but currently we don't have a good way to express that.
Change-Id: I9fdfc7584670aa09c5a01f6b2803f2043aaddb65
Reviewed-on: https://go-review.googlesource.com/c/go/+/441938
Run-TryBot: Cherry Mui <cherryyz@google.com>
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: David Chase <drchase@google.com>
