ART: Use StackReference in Quick Stack Frame

The method reference at the bottom of a quick frame is a stack
reference and not a native pointer. This is important for 64b
architectures, where the notions do not coincide.

Change key methods to have StackReference<mirror::ArtMethod>*
parameter instead of mirror::ArtMethod**. Make changes to
invoke stubs for 64b archs, change the frame setup for JNI code
(both generic JNI and compilers), tie up loose ends.

Tested on x86 and x86-64 with host tests. On x86-64, tests succeed
with jni compiler activated. x86-64 QCG was not tested.

Tested on ARM32 with device tests.

Fix ARM64 not saving x19 (used for wSUSPEND) on upcalls.

Tested on ARM64 in interpreter-only + generic-jni mode.

Fix ARM64 JNI Compiler to work with the CL.

Tested on ARM64 in interpreter-only + jni compiler.

Change-Id: I77931a0cbadd04d163b3eb8d6f6a6f8740578f13
diff --git a/runtime/stack.cc b/runtime/stack.cc
index be1fba4..6633159 100644
--- a/runtime/stack.cc
+++ b/runtime/stack.cc
@@ -205,16 +205,16 @@
 }
 
 uintptr_t StackVisitor::GetReturnPc() const {
-  mirror::ArtMethod** sp = GetCurrentQuickFrame();
+  byte* sp = reinterpret_cast<byte*>(GetCurrentQuickFrame());
   DCHECK(sp != NULL);
-  byte* pc_addr = reinterpret_cast<byte*>(sp) + GetMethod()->GetReturnPcOffsetInBytes();
+  byte* pc_addr = sp + GetMethod()->GetReturnPcOffsetInBytes();
   return *reinterpret_cast<uintptr_t*>(pc_addr);
 }
 
 void StackVisitor::SetReturnPc(uintptr_t new_ret_pc) {
-  mirror::ArtMethod** sp = GetCurrentQuickFrame();
+  byte* sp = reinterpret_cast<byte*>(GetCurrentQuickFrame());
   CHECK(sp != NULL);
-  byte* pc_addr = reinterpret_cast<byte*>(sp) + GetMethod()->GetReturnPcOffsetInBytes();
+  byte* pc_addr = sp + GetMethod()->GetReturnPcOffsetInBytes();
   *reinterpret_cast<uintptr_t*>(pc_addr) = new_ret_pc;
 }
 
@@ -307,7 +307,7 @@
     if (cur_quick_frame_ != NULL) {  // Handle quick stack frames.
       // Can't be both a shadow and a quick fragment.
       DCHECK(current_fragment->GetTopShadowFrame() == NULL);
-      mirror::ArtMethod* method = *cur_quick_frame_;
+      mirror::ArtMethod* method = cur_quick_frame_->AsMirrorPtr();
       while (method != NULL) {
         SanityCheckFrame();
         bool should_continue = VisitFrame();
@@ -352,9 +352,9 @@
         }
         cur_quick_frame_pc_ = return_pc;
         byte* next_frame = reinterpret_cast<byte*>(cur_quick_frame_) + frame_size;
-        cur_quick_frame_ = reinterpret_cast<mirror::ArtMethod**>(next_frame);
+        cur_quick_frame_ = reinterpret_cast<StackReference<mirror::ArtMethod>*>(next_frame);
         cur_depth_++;
-        method = *cur_quick_frame_;
+        method = cur_quick_frame_->AsMirrorPtr();
       }
     } else if (cur_shadow_frame_ != NULL) {
       do {