diff options
Diffstat (limited to 'src/runtime/mgc0.go')
| -rw-r--r-- | src/runtime/mgc0.go | 14 |
1 files changed, 12 insertions, 2 deletions
diff --git a/src/runtime/mgc0.go b/src/runtime/mgc0.go index ce5c290ef..760d2a545 100644 --- a/src/runtime/mgc0.go +++ b/src/runtime/mgc0.go @@ -92,13 +92,24 @@ const ( // but if we do that, Go inserts a write barrier on *dst = src. //go:nosplit func writebarrierptr(dst *uintptr, src uintptr) { + *dst = src + writebarrierptr_nostore(dst, src) +} + +// Like writebarrierptr, but the store has already been applied. +// Do not reapply. +//go:nosplit +func writebarrierptr_nostore(dst *uintptr, src uintptr) { + if getg() == nil { // very low-level startup + return + } + if src != 0 && (src < _PageSize || src == _PoisonGC || src == _PoisonStack) { onM(func() { gothrow("bad pointer in write barrier") }) } mp := acquirem() if mp.inwb { - *dst = src releasem(mp) return } @@ -112,7 +123,6 @@ func writebarrierptr(dst *uintptr, src uintptr) { mp.scalararg[1] = oldscalar1 mp.inwb = false releasem(mp) - // *dst = src is done inside of the write barrier. } //go:nosplit |