Merge from trunk revision 257610.

From-SVN: r257612

4 files changed, 69 insertions, 71 deletions

diff --git a/libgo/go/runtime/atomic_pointer.go b/libgo/go/runtime/atomic_pointer.go
new file mode 100644
index 0000000..b66ef58
--- /dev/null
+++ b/libgo/go/runtime/atomic_pointer.go
@@ -0,0 +1,69 @@
+// Copyright 2009 The Go Authors. All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package runtime
+
+import (
+	"runtime/internal/atomic"
+	"unsafe"
+)
+
+// These functions cannot have go:noescape annotations,
+// because while ptr does not escape, new does.
+// If new is marked as not escaping, the compiler will make incorrect
+// escape analysis decisions about the pointer value being stored.
+// Instead, these are wrappers around the actual atomics (casp1 and so on)
+// that use noescape to convey which arguments do not escape.
+
+// atomicstorep performs *ptr = new atomically and invokes a write barrier.
+//
+//go:nosplit
+func atomicstorep(ptr unsafe.Pointer, new unsafe.Pointer) {
+	writebarrierptr_prewrite((*uintptr)(ptr), uintptr(new))
+	atomic.StorepNoWB(noescape(ptr), new)
+}
+
+//go:nosplit
+func casp(ptr *unsafe.Pointer, old, new unsafe.Pointer) bool {
+	// The write barrier is only necessary if the CAS succeeds,
+	// but since it needs to happen before the write becomes
+	// public, we have to do it conservatively all the time.
+	writebarrierptr_prewrite((*uintptr)(unsafe.Pointer(ptr)), uintptr(new))
+	return atomic.Casp1((*unsafe.Pointer)(noescape(unsafe.Pointer(ptr))), noescape(old), new)
+}
+
+// Like above, but implement in terms of sync/atomic's uintptr operations.
+// We cannot just call the runtime routines, because the race detector expects
+// to be able to intercept the sync/atomic forms but not the runtime forms.
+
+//go:linkname sync_atomic_StoreUintptr sync_atomic.StoreUintptr
+func sync_atomic_StoreUintptr(ptr *uintptr, new uintptr)
+
+//go:linkname sync_atomic_StorePointer sync_atomic.StorePointer
+//go:nosplit
+func sync_atomic_StorePointer(ptr *unsafe.Pointer, new unsafe.Pointer) {
+	writebarrierptr_prewrite((*uintptr)(unsafe.Pointer(ptr)), uintptr(new))
+	sync_atomic_StoreUintptr((*uintptr)(unsafe.Pointer(ptr)), uintptr(new))
+}
+
+//go:linkname sync_atomic_SwapUintptr sync_atomic.SwapUintptr
+func sync_atomic_SwapUintptr(ptr *uintptr, new uintptr) uintptr
+
+//go:linkname sync_atomic_SwapPointer sync_atomic.SwapPointer
+//go:nosplit
+func sync_atomic_SwapPointer(ptr *unsafe.Pointer, new unsafe.Pointer) unsafe.Pointer {
+	writebarrierptr_prewrite((*uintptr)(unsafe.Pointer(ptr)), uintptr(new))
+	old := unsafe.Pointer(sync_atomic_SwapUintptr((*uintptr)(noescape(unsafe.Pointer(ptr))), uintptr(new)))
+	return old
+}
+
+//go:linkname sync_atomic_CompareAndSwapUintptr sync_atomic.CompareAndSwapUintptr
+func sync_atomic_CompareAndSwapUintptr(ptr *uintptr, old, new uintptr) bool
+
+//go:linkname sync_atomic_CompareAndSwapPointer sync_atomic.CompareAndSwapPointer
+//go:nosplit
+func sync_atomic_CompareAndSwapPointer(ptr *unsafe.Pointer, old, new unsafe.Pointer) bool {
+	writebarrierptr_prewrite((*uintptr)(unsafe.Pointer(ptr)), uintptr(new))
+	return sync_atomic_CompareAndSwapUintptr((*uintptr)(noescape(unsafe.Pointer(ptr))), uintptr(old), uintptr(new))
+}
diff --git a/libgo/go/runtime/extern.go b/libgo/go/runtime/extern.go
index 36787e3..b3afd10 100644
--- a/libgo/go/runtime/extern.go
+++ b/libgo/go/runtime/extern.go
@@ -157,10 +157,6 @@ package runtime
 
 import "runtime/internal/sys"
 
-// Gosched yields the processor, allowing other goroutines to run.  It does not
-// suspend the current goroutine, so execution resumes automatically.
-func Gosched()
-
 // Caller reports file and line number information about function invocations on
 // the calling goroutine's stack. The argument skip is the number of stack frames
 // to ascend, with 0 identifying the caller of Caller.  (For historical reasons the
diff --git a/libgo/go/runtime/stubs.go b/libgo/go/runtime/stubs.go
index fa3b1ce..bda2c69 100644
--- a/libgo/go/runtime/stubs.go
+++ b/libgo/go/runtime/stubs.go
@@ -5,7 +5,6 @@
 package runtime
 
 import (
-	"runtime/internal/atomic"
 	"runtime/internal/sys"
 	"unsafe"
 )
@@ -307,19 +306,6 @@ func setSupportAES(v bool) {
 	support_aes = v
 }
 
-// Here for gccgo until we port atomic_pointer.go and mgc.go.
-//go:nosplit
-func casp(ptr *unsafe.Pointer, old, new unsafe.Pointer) bool {
-	if !atomic.Casp1((*unsafe.Pointer)(noescape(unsafe.Pointer(ptr))), noescape(old), new) {
-		return false
-	}
-	return true
-}
-
-// Here for gccgo until we port lock_*.go.
-func lock(l *mutex)
-func unlock(l *mutex)
-
 // Here for gccgo.
 func errno() int
 
@@ -327,9 +313,6 @@ func errno() int
 func entersyscall(int32)
 func entersyscallblock(int32)
 
-// Here for gccgo until we port mgc.go.
-func GC()
-
 // For gccgo to call from C code, so that the C code and the Go code
 // can share the memstats variable for now.
 //go:linkname getMstats runtime.getMstats
@@ -337,22 +320,6 @@ func getMstats() *mstats {
 	return &memstats
 }
 
-// Temporary for gccgo until we port mem_GOOS.go.
-func sysAlloc(n uintptr, sysStat *uint64) unsafe.Pointer
-func sysFree(v unsafe.Pointer, n uintptr, sysStat *uint64)
-
-// Temporary for gccgo until we port malloc.go
-func persistentalloc(size, align uintptr, sysStat *uint64) unsafe.Pointer
-
-// Temporary for gccgo until we port mheap.go
-func setprofilebucket(p unsafe.Pointer, b *bucket)
-
-// Temporary for gccgo until we port atomic_pointer.go.
-//go:nosplit
-func atomicstorep(ptr unsafe.Pointer, new unsafe.Pointer) {
-	atomic.StorepNoWB(noescape(ptr), new)
-}
-
 // Get signal trampoline, written in C.
 func getSigtramp() uintptr
 
diff --git a/libgo/go/sync/atomic/atomic.c b/libgo/go/sync/atomic/atomic.c
index 32cbf03..07a4306 100644
--- a/libgo/go/sync/atomic/atomic.c
+++ b/libgo/go/sync/atomic/atomic.c
@@ -62,16 +62,6 @@ SwapUintptr (uintptr_t *addr, uintptr_t new)
   return __atomic_exchange_n (addr, new, __ATOMIC_SEQ_CST);
 }
 
-void *SwapPointer (void **, void *)
-  __asm__ (GOSYM_PREFIX "sync_atomic.SwapPointer")
-  __attribute__ ((no_split_stack));
-
-void *
-SwapPointer (void **addr, void *new)
-{
-  return __atomic_exchange_n (addr, new, __ATOMIC_SEQ_CST);
-}
-
 _Bool CompareAndSwapInt32 (int32_t *, int32_t, int32_t)
   __asm__ (GOSYM_PREFIX "sync_atomic.CompareAndSwapInt32")
   __attribute__ ((no_split_stack));
@@ -126,16 +116,6 @@ CompareAndSwapUintptr (uintptr_t *val, uintptr_t old, uintptr_t new)
   return __sync_bool_compare_and_swap (val, old, new);
 }
 
-_Bool CompareAndSwapPointer (void **, void *, void *)
-  __asm__ (GOSYM_PREFIX "sync_atomic.CompareAndSwapPointer")
-  __attribute__ ((no_split_stack));
-
-_Bool
-CompareAndSwapPointer (void **val, void *old, void *new)
-{
-  return __sync_bool_compare_and_swap (val, old, new);
-}
-
 int32_t AddInt32 (int32_t *, int32_t)
   __asm__ (GOSYM_PREFIX "sync_atomic.AddInt32")
   __attribute__ ((no_split_stack));
@@ -357,17 +337,3 @@ StoreUintptr (uintptr_t *addr, uintptr_t val)
   while (! __sync_bool_compare_and_swap (addr, v, val))
     v = *addr;
 }
-
-void StorePointer (void **addr, void *val)
-  __asm__ (GOSYM_PREFIX "sync_atomic.StorePointer")
-  __attribute__ ((no_split_stack));
-
-void
-StorePointer (void **addr, void *val)
-{
-  void *v;
-
-  v = *addr;
-  while (! __sync_bool_compare_and_swap (addr, v, val))
-    v = *addr;
-}