Added more comments

1 files changed, 6 insertions, 0 deletions

diff --git a/pkg/atomicbitops/aligned_32bit_unsafe.go b/pkg/atomicbitops/aligned_32bit_unsafe.go
index a5c762f67..200fc0092 100644
--- a/pkg/atomicbitops/aligned_32bit_unsafe.go
+++ b/pkg/atomicbitops/aligned_32bit_unsafe.go
@@ -35,6 +35,9 @@ type AlignedAtomicInt64 struct {
 }
 
 func (aa *AlignedAtomicInt64) ptr() *int64 {
+	// In the 15-byte aa.value, there are guaranteed to be 8 contiguous
+	// bytes with 64-bit alignment. We find an address in this range by
+	// adding 7, then clear the 3 least significant bits to get its start.
 	return (*int64)(unsafe.Pointer((uintptr(unsafe.Pointer(&aa.value)) + 7) &^ 7))
 }
 
@@ -67,6 +70,9 @@ type AlignedAtomicUint64 struct {
 }
 
 func (aa *AlignedAtomicUint64) ptr() *uint64 {
+	// In the 15-byte aa.value, there are guaranteed to be 8 contiguous
+	// bytes with 64-bit alignment. We find an address in this range by
+	// adding 7, then clear the 3 least significant bits to get its start.
 	return (*uint64)(unsafe.Pointer((uintptr(unsafe.Pointer(&aa.value)) + 7) &^ 7))
 }