Move more functionality from CEntryStub to the helper...

src/macro-assembler-arm.cc

 // Copyright 2006-2008 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 288 matching lines @@
   mov(ip, Operand(ExternalReference(Top::k_context_address)));
   str(cp, MemOperand(ip));
 
   // Setup argc and the builtin function in callee-saved registers.
   mov(r4, Operand(r0));
   mov(r5, Operand(r1));
 
   // Compute the argv pointer and keep it in a callee-saved register.
   add(r6, fp, Operand(r4, LSL, kPointerSizeLog2));
   add(r6, r6, Operand(ExitFrameConstants::kPPDisplacement - kPointerSize));
+
+  // Save the state of all registers to the stack from the memory
+  // location. This is needed to allow nested break points.
+  if (type == StackFrame::EXIT_DEBUG) {
+    // Use sp as base to push.
+    CopyRegistersFromMemoryToStack(sp, kJSCallerSaved);
+  }
 }
 
 
-void MacroAssembler::LeaveExitFrame() {
+void MacroAssembler::LeaveExitFrame(StackFrame::Type type) {
+  // Restore the memory copy of the registers by digging them out from
+  // the stack. This is needed to allow nested break points.
+  if (type == StackFrame::EXIT_DEBUG) {
+    // This code intentionally clobbers r2 and r3.
+    const int kCallerSavedSize = kNumJSCallerSaved * kPointerSize;
+    const int kOffset = ExitFrameConstants::kDebugMarkOffset - kCallerSavedSize;
+    add(r3, fp, Operand(kOffset));
+    CopyRegistersFromStackToMemory(r3, r2, kJSCallerSaved);
+  }
+
   // Clear top frame.
   mov(r3, Operand(0));
   mov(ip, Operand(ExternalReference(Top::k_c_entry_fp_address)));
   str(r3, MemOperand(ip));
 
   // Restore current context from top and clear it in debug mode.
   mov(ip, Operand(ExternalReference(Top::k_context_address)));
   ldr(cp, MemOperand(ip));
   if (kDebug) {
     str(r3, MemOperand(ip));
@@ skipping 477 matching lines @@
 #endif
   mov(r0, Operand(p0));
   push(r0);
   mov(r0, Operand(Smi::FromInt(p1 - p0)));
   push(r0);
   CallRuntime(Runtime::kAbort, 2);
   // will not return here
 }
 
 } }  // namespace v8::internal