1 files changed, 60 insertions, 1 deletions
diff --git a/libgo/go/runtime/export_test.go b/libgo/go/runtime/export_test.go
index 5e798e3e3a3..7f4811c5a0c 100644
--- a/libgo/go/runtime/export_test.go
+++ b/libgo/go/runtime/export_test.go
@@ -21,7 +21,6 @@ import (
 //var Fcmp64 = fcmp64
 //var Fintto64 = fintto64
 //var F64toint = f64toint
-//var Sqrt = sqrt
 
 var Entersyscall = entersyscall
 var Exitsyscall = exitsyscall
@@ -372,6 +371,8 @@ func (rw *RWMutex) Unlock() {
 	rw.rw.unlock()
 }
 
+const RuntimeHmapSize = unsafe.Sizeof(hmap{})
+
 func MapBucketsCount(m map[int]int) int {
 	h := *(**hmap)(unsafe.Pointer(&m))
 	return 1 << h.B
@@ -395,3 +396,61 @@ func LockOSCounts() (external, internal uint32) {
 	}
 	return g.m.lockedExt, g.m.lockedInt
 }
+
+func KeepNArenaHints(n int) {
+	hint := mheap_.arenaHints
+	for i := 1; i < n; i++ {
+		hint = hint.next
+		if hint == nil {
+			return
+		}
+	}
+	hint.next = nil
+}
+
+// MapNextArenaHint reserves a page at the next arena growth hint,
+// preventing the arena from growing there, and returns the range of
+// addresses that are no longer viable.
+func MapNextArenaHint() (start, end uintptr) {
+	hint := mheap_.arenaHints
+	addr := hint.addr
+	if hint.down {
+		start, end = addr-heapArenaBytes, addr
+		addr -= physPageSize
+	} else {
+		start, end = addr, addr+heapArenaBytes
+	}
+	sysReserve(unsafe.Pointer(addr), physPageSize)
+	return
+}
+
+func GetNextArenaHint() uintptr {
+	return mheap_.arenaHints.addr
+}
+
+type G = g
+
+func Getg() *G {
+	return getg()
+}
+
+//go:noinline
+func PanicForTesting(b []byte, i int) byte {
+	return unexportedPanicForTesting(b, i)
+}
+
+//go:noinline
+func unexportedPanicForTesting(b []byte, i int) byte {
+	return b[i]
+}
+
+func G0StackOverflow() {
+	systemstack(func() {
+		stackOverflow(nil)
+	})
+}
+
+func stackOverflow(x *byte) {
+	var buf [256]byte
+	stackOverflow(&buf[0])
+}