Revert "VM: New calling convention for generated code."

runtime/vm/deferred_objects.cc

Index: runtime/vm/deferred_objects.cc
diff --git a/runtime/vm/deferred_objects.cc b/runtime/vm/deferred_objects.cc
index 6aac45a6c392a200830157eb44d2c61baadb3381..a647af1768a356b2db103551cd94df8463f4cd59 100644
--- a/runtime/vm/deferred_objects.cc
+++ b/runtime/vm/deferred_objects.cc
@@ -161,7 +161,11 @@ void DeferredPcMarker::Materialize(DeoptContext* deopt_context) {
   uword* dest_addr = reinterpret_cast<uword*>(slot());
   Function& function = Function::Handle(zone);
   function ^= deopt_context->ObjectAt(index_);
-  ASSERT(!function.IsNull());
+  if (function.IsNull()) {
+    // Callee's PC marker is not used (pc of Deoptimize stub). Set to 0.
+    *dest_addr = 0;
+    return;
+  }
   const Error& error = Error::Handle(zone,
       Compiler::EnsureUnoptimizedCode(thread, function));
   if (!error.IsNull()) {
@@ -170,7 +174,9 @@ void DeferredPcMarker::Materialize(DeoptContext* deopt_context) {
   const Code& code = Code::Handle(zone, function.unoptimized_code());
   ASSERT(!code.IsNull());
   ASSERT(function.HasCode());
-  *reinterpret_cast<RawObject**>(dest_addr) = code.raw();
+  const intptr_t pc_marker =
+      code.EntryPoint() + Assembler::EntryPointToPcMarkerOffset();
+  *dest_addr = pc_marker;
 
   if (FLAG_trace_deoptimization_verbose) {
     OS::PrintErr("materializing pc marker at 0x%" Px ": %s, %s\n",