runtime: implement experiment to replace heap bitmap with alloc headers

[gostls13.git] / src / runtime / cgocall.go

diff --git a/src/runtime/cgocall.go b/src/runtime/cgocall.go
index 6c2fd8f907a5f6cd48b45bf9b2a860a9fb0dbbf7..f2dd98702d18b3aaf46ca390eb331b701a975689 100644 (file)
--- a/src/runtime/cgocall.go
+++ b/src/runtime/cgocall.go
@@ -664,19 +664,32 @@ func cgoCheckUnknownPointer(p unsafe.Pointer, msg string) (base, i uintptr) {
                if base == 0 {
                        return
                }
-               n := span.elemsize
-               hbits := heapBitsForAddr(base, n)
-               for {
-                       var addr uintptr
-                       if hbits, addr = hbits.next(); addr == 0 {
-                               break
+               if goexperiment.AllocHeaders {
+                       tp := span.typePointersOfUnchecked(base)
+                       for {
+                               var addr uintptr
+                               if tp, addr = tp.next(base + span.elemsize); addr == 0 {
+                                       break
+                               }
+                               pp := *(*unsafe.Pointer)(unsafe.Pointer(addr))
+                               if cgoIsGoPointer(pp) && !isPinned(pp) {
+                                       panic(errorString(msg))
+                               }
                        }
-                       pp := *(*unsafe.Pointer)(unsafe.Pointer(addr))
-                       if cgoIsGoPointer(pp) && !isPinned(pp) {
-                               panic(errorString(msg))
+               } else {
+                       n := span.elemsize
+                       hbits := heapBitsForAddr(base, n)
+                       for {
+                               var addr uintptr
+                               if hbits, addr = hbits.next(); addr == 0 {
+                                       break
+                               }
+                               pp := *(*unsafe.Pointer)(unsafe.Pointer(addr))
+                               if cgoIsGoPointer(pp) && !isPinned(pp) {
+                                       panic(errorString(msg))
+                               }
                        }
                }
-
                return
        }