libgo: update to Go1.12beta2

    
    Reviewed-on: https://go-review.googlesource.com/c/158019

gotools/:
	* Makefile.am (go_cmd_vet_files): Update for Go1.12beta2 release.
	(GOTOOLS_TEST_TIMEOUT): Increase to 600.
	(check-runtime): Export LD_LIBRARY_PATH before computing GOARCH
	and GOOS.
	(check-vet): Copy golang.org/x/tools into check-vet-dir.
	* Makefile.in: Regenerate.

gcc/testsuite/:
	* go.go-torture/execute/names-1.go: Stop using debug/xcoff, which
	is no longer externally visible.

From-SVN: r268084

2 files changed, 30 insertions, 16 deletions

diff --git a/libgo/go/container/heap/heap.go b/libgo/go/container/heap/heap.go
index 67b5efcac7e..2e09da8613a 100644
--- a/libgo/go/container/heap/heap.go
+++ b/libgo/go/container/heap/heap.go
@@ -38,7 +38,7 @@ type Interface interface {
 // Init establishes the heap invariants required by the other routines in this package.
 // Init is idempotent with respect to the heap invariants
 // and may be called whenever the heap invariants may have been invalidated.
-// Its complexity is O(n) where n = h.Len().
+// The complexity is O(n) where n = h.Len().
 func Init(h Interface) {
 	// heapify
 	n := h.Len()
@@ -47,18 +47,16 @@ func Init(h Interface) {
 	}
 }
 
-// Push pushes the element x onto the heap. The complexity is
-// O(log(n)) where n = h.Len().
-//
+// Push pushes the element x onto the heap.
+// The complexity is O(log n) where n = h.Len().
 func Push(h Interface, x interface{}) {
 	h.Push(x)
 	up(h, h.Len()-1)
 }
 
-// Pop removes the minimum element (according to Less) from the heap
-// and returns it. The complexity is O(log(n)) where n = h.Len().
-// It is equivalent to Remove(h, 0).
-//
+// Pop removes and returns the minimum element (according to Less) from the heap.
+// The complexity is O(log n) where n = h.Len().
+// Pop is equivalent to Remove(h, 0).
 func Pop(h Interface) interface{} {
 	n := h.Len() - 1
 	h.Swap(0, n)
@@ -66,9 +64,8 @@ func Pop(h Interface) interface{} {
 	return h.Pop()
 }
 
-// Remove removes the element at index i from the heap.
-// The complexity is O(log(n)) where n = h.Len().
-//
+// Remove removes and returns the element at index i from the heap.
+// The complexity is O(log n) where n = h.Len().
 func Remove(h Interface, i int) interface{} {
 	n := h.Len() - 1
 	if n != i {
@@ -83,7 +80,7 @@ func Remove(h Interface, i int) interface{} {
 // Fix re-establishes the heap ordering after the element at index i has changed its value.
 // Changing the value of the element at index i and then calling Fix is equivalent to,
 // but less expensive than, calling Remove(h, i) followed by a Push of the new value.
-// The complexity is O(log(n)) where n = h.Len().
+// The complexity is O(log n) where n = h.Len().
 func Fix(h Interface, i int) {
 	if !down(h, i, h.Len()) {
 		up(h, i)
diff --git a/libgo/go/container/list/list.go b/libgo/go/container/list/list.go
index dc4260e1316..b8b599aabb1 100644
--- a/libgo/go/container/list/list.go
+++ b/libgo/go/container/list/list.go
@@ -116,6 +116,23 @@ func (l *List) remove(e *Element) *Element {
 	return e
 }
 
+// move moves e to next to at and returns e.
+func (l *List) move(e, at *Element) *Element {
+	if e == at {
+		return e
+	}
+	e.prev.next = e.next
+	e.next.prev = e.prev
+
+	n := at.next
+	at.next = e
+	e.prev = at
+	e.next = n
+	n.prev = e
+
+	return e
+}
+
 // Remove removes e from l if e is an element of list l.
 // It returns the element value e.Value.
 // The element must not be nil.
@@ -170,7 +187,7 @@ func (l *List) MoveToFront(e *Element) {
 		return
 	}
 	// see comment in List.Remove about initialization of l
-	l.insert(l.remove(e), &l.root)
+	l.move(e, &l.root)
 }
 
 // MoveToBack moves element e to the back of list l.
@@ -181,7 +198,7 @@ func (l *List) MoveToBack(e *Element) {
 		return
 	}
 	// see comment in List.Remove about initialization of l
-	l.insert(l.remove(e), l.root.prev)
+	l.move(e, l.root.prev)
 }
 
 // MoveBefore moves element e to its new position before mark.
@@ -191,7 +208,7 @@ func (l *List) MoveBefore(e, mark *Element) {
 	if e.list != l || e == mark || mark.list != l {
 		return
 	}
-	l.insert(l.remove(e), mark.prev)
+	l.move(e, mark.prev)
 }
 
 // MoveAfter moves element e to its new position after mark.
@@ -201,7 +218,7 @@ func (l *List) MoveAfter(e, mark *Element) {
 	if e.list != l || e == mark || mark.list != l {
 		return
 	}
-	l.insert(l.remove(e), mark)
+	l.move(e, mark)
 }
 
 // PushBackList inserts a copy of an other list at the back of list l.