Fix for issue 14790 - Crash when using dartium devtools

runtime/vm/assembler_x64.cc

Index: runtime/vm/assembler_x64.cc
===================================================================
--- runtime/vm/assembler_x64.cc	(revision 29988)
+++ runtime/vm/assembler_x64.cc	(working copy)
@@ -2667,17 +2667,11 @@
 }
 
 
-void Assembler::LeaveFrameWithPP() {
-  movq(PP, Address(RBP, -2 * kWordSize));
-  LeaveFrame();
-}
-
-
 void Assembler::ReturnPatchable() {
   // This sequence must have a fixed size so that it can be patched by the
   // debugger.
   intptr_t start = buffer_.GetPosition();
-  LeaveFrameWithPP();
+  LeaveDartFrame();
   ret();
   nop(4);
   ASSERT((buffer_.GetPosition() - start) == 13);
@@ -2825,6 +2819,13 @@
 }
 
 
+void Assembler::LeaveDartFrame() {
+  // Restore caller's PP register that was pushed in EnterDartFrame.
+  movq(PP, Address(RBP, (kSavedCallerPpSlotFromFp * kWordSize)));
+  LeaveFrame();
+}
+
+
 // On entry to a function compiled for OSR, the caller's frame pointer, the
 // stack locals, and any copied parameters are already in place.  The frame
 // pointer is already set up.  The PC marker is not correct for the
@@ -2862,17 +2863,20 @@
 }
 
 
-void Assembler::EnterStubFrame() {
+void Assembler::EnterStubFrame(bool load_pp) {
   EnterFrame(0);
   pushq(Immediate(0));  // Push 0 in the saved PC area for stub frames.
+  pushq(PP);  // Save caller's pool pointer
+  if (load_pp) {
+    LoadPoolPointer(PP);
+  }
 }
 
 
-void Assembler::EnterStubFrameWithPP() {
-  EnterFrame(0);
-  pushq(Immediate(0));  // Push 0 in the saved PC area for stub frames.
-  pushq(PP);  // Save caller's pool pointer
-  LoadPoolPointer(PP);
+void Assembler::LeaveStubFrame() {

[zra, 2013/11/07 19:28:17]

This looks the same as LeaveDartFrame. I can see the benefit of using names
Enter/LeaveStubFrame and Enter/LeaveDartFrame, but would it make sense to have
LeaveStubFrame and LeaveDartFrame call the same function?

[siva, 2013/11/07 23:08:19]

I have tried to be consistent with how it is done in ARM and MIPs,
maybe I could do another CL after this to factor out the code into a helper
method that could be called from here.

+  // Restore caller's PP register that was pushed in EnterStubFrame.
+  movq(PP, Address(RBP, (kSavedCallerPpSlotFromFp * kWordSize)));
+  LeaveFrame();
 }