runtime: change lfstack support to taggedPointer

This is a refactoring with no change in behavior, in preparation
for future netpoll work.

For #59545

Change-Id: I493c5fd0f49f31b75787f7b5b89c544bed73f64f
Reviewed-on: https://go-review.googlesource.com/c/go/+/484836
TryBot-Result: Gopher Robot <gobot@golang.org>
Reviewed-by: Bryan Mills <bcmills@google.com>
Auto-Submit: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Michael Knyszek <mknyszek@google.com>
Run-TryBot: Ian Lance Taylor <iant@golang.org>
Reviewed-by: Orlando Labao <orlando.labao43@gmail.com>

1 files changed, 8 insertions, 0 deletions

diff --git a/src/runtime/lfstack.go b/src/runtime/lfstack.go
index 306a8e888a..a91ae64e53 100644
--- a/src/runtime/lfstack.go
+++ b/src/runtime/lfstack.go
@@ -67,3 +67,11 @@ func lfnodeValidate(node *lfnode) {
 		throw("bad lfnode address")
 	}
 }
+
+func lfstackPack(node *lfnode, cnt uintptr) uint64 {
+	return uint64(taggedPointerPack(unsafe.Pointer(node), cnt))
+}
+
+func lfstackUnpack(val uint64) *lfnode {
+	return (*lfnode)(taggedPointer(val).pointer())
+}