Revert "Revert "Don't use the compiler driver for method resolution.""

This reverts commit c88ef3a10c474045a3476a02ae75d07ddd3230b7.

Change-Id: I0ed88a48b313a8d28bc39fae40631123aadb13ef
diff --git a/compiler/optimizing/code_generator_x86_64.cc b/compiler/optimizing/code_generator_x86_64.cc
index 534ee1c..4618be9 100644
--- a/compiler/optimizing/code_generator_x86_64.cc
+++ b/compiler/optimizing/code_generator_x86_64.cc
@@ -802,12 +802,17 @@
   CpuRegister temp = temp_in.AsRegister<CpuRegister>();
   size_t method_offset = mirror::Class::EmbeddedVTableEntryOffset(
       invoke->GetVTableIndex(), kX86_64PointerSize).SizeValue();
-  LocationSummary* locations = invoke->GetLocations();
-  Location receiver = locations->InAt(0);
+
+  // Use the calling convention instead of the location of the receiver, as
+  // intrinsics may have put the receiver in a different register. In the intrinsics
+  // slow path, the arguments have been moved to the right place, so here we are
+  // guaranteed that the receiver is the first register of the calling convention.
+  InvokeDexCallingConvention calling_convention;
+  Register receiver = calling_convention.GetRegisterAt(0);
+
   size_t class_offset = mirror::Object::ClassOffset().SizeValue();
-  DCHECK(receiver.IsRegister());
   // /* HeapReference<Class> */ temp = receiver->klass_
-  __ movl(temp, Address(receiver.AsRegister<CpuRegister>(), class_offset));
+  __ movl(temp, Address(CpuRegister(receiver), class_offset));
   MaybeRecordImplicitNullCheck(invoke);
   // Instead of simply (possibly) unpoisoning `temp` here, we should
   // emit a read barrier for the previous class reference load.