runtime/map: update comment for gc/reflect

update comment cause gc/reflect.go has been moved to reflectdata/reflect.go

In the commit (attach below), gc/reflect.go is moved to reflectdata/reflect.go
So the  comment referring gc/reflect.go should be updated to reflectdata/reflect.go

There maybe other places that refers gc/reflect.go that should be updated.
I would work around it soon.

commit:
de65151
e4895ab

Change-Id: Ieed5c48049ffe6889c08e164972fc7825653ac05
GitHub-Last-Rev: eec9c23
GitHub-Pull-Request: #45421
Reviewed-on: https://go-review.googlesource.com/c/go/+/307930
Reviewed-by: Keith Randall <[email protected]>
Trust: Emmanuel Odeke <[email protected]>

Author: MakDon

src/cmd/compile/internal/walk/range.go

@@ -168,7 +168,9 @@ func walkRange(nrange *ir.RangeStmt) ir.Node {
 
 		hit := nrange.Prealloc
 		th := hit.Type()
-		keysym := th.Field(0).Sym  // depends on layout of iterator struct.  See reflect.go:MapIterType
+		// depends on layout of iterator struct.
+		// See cmd/compile/internal/reflectdata/reflect.go:MapIterType
+		keysym := th.Field(0).Sym  
 		elemsym := th.Field(1).Sym // ditto
 
 		fn := typecheck.LookupRuntime("mapiterinit")

src/runtime/map.go

@@ -113,7 +113,7 @@ func isEmpty(x uint8) bool {
 
 // A header for a Go map.
 type hmap struct {
-	// Note: the format of the hmap is also encoded in cmd/compile/internal/gc/reflect.go.
+	// Note: the format of the hmap is also encoded in cmd/compile/internal/reflectdata/reflect.go.
 	// Make sure this stays in sync with the compiler's definition.
 	count     int // # live cells == size of map.  Must be first (used by len() builtin)
 	flags     uint8
@@ -159,11 +159,11 @@ type bmap struct {
 }
 
 // A hash iteration structure.
-// If you modify hiter, also change cmd/compile/internal/gc/reflect.go to indicate
+// If you modify hiter, also change cmd/compile/internal/reflectdata/reflect.go to indicate
 // the layout of this structure.
 type hiter struct {
-	key         unsafe.Pointer // Must be in first position.  Write nil to indicate iteration end (see cmd/compile/internal/gc/range.go).
-	elem        unsafe.Pointer // Must be in second position (see cmd/compile/internal/gc/range.go).
+	key         unsafe.Pointer // Must be in first position.  Write nil to indicate iteration end (see cmd/compile/internal/walk/range.go).
+	elem        unsafe.Pointer // Must be in second position (see cmd/compile/internal/walk/range.go).
 	t           *maptype
 	h           *hmap
 	buckets     unsafe.Pointer // bucket ptr at hash_iter initialization time
@@ -810,7 +810,7 @@ func mapiterinit(t *maptype, h *hmap, it *hiter) {
 	}
 
 	if unsafe.Sizeof(hiter{})/sys.PtrSize != 12 {
-		throw("hash_iter size incorrect") // see cmd/compile/internal/gc/reflect.go
+		throw("hash_iter size incorrect") // see cmd/compile/internal/reflectdata/reflect.go
 	}
 	it.t = t
 	it.h = h