Internalize strings in-place

src/compiler/access-builder.cc

Index: src/compiler/access-builder.cc
diff --git a/src/compiler/access-builder.cc b/src/compiler/access-builder.cc
index 57eb86a711bf1f5524a2c9b61e136b40fa745ae8..33a828f4f8b264c63499ac94f31fa08eddc1b7ec 100644
--- a/src/compiler/access-builder.cc
+++ b/src/compiler/access-builder.cc
@@ -500,6 +500,14 @@ FieldAccess AccessBuilder::ForConsStringSecond() {
 }
 
 // static
+FieldAccess AccessBuilder::ForThinStringActual() {
+  FieldAccess access = {
+      kTaggedBase,    ThinString::kActualOffset,    Handle<Name>(),
+      Type::String(), MachineType::TaggedPointer(), kPointerWriteBarrier};
+  return access;
+}
+
+// static
 FieldAccess AccessBuilder::ForSlicedStringOffset() {
   FieldAccess access = {
       kTaggedBase,         SlicedString::kOffsetOffset, Handle<Name>(),