[liveedit] reimplement frame restarting.

src/arm/macro-assembler-arm.cc

Index: src/arm/macro-assembler-arm.cc
diff --git a/src/arm/macro-assembler-arm.cc b/src/arm/macro-assembler-arm.cc
index ea0c4cb1d6759bffbab56cc2001e6b83e3d6c4ba..2e00e31e3ce9a63c487773e6459a100e23ec4caf 100644
--- a/src/arm/macro-assembler-arm.cc
+++ b/src/arm/macro-assembler-arm.cc
@@ -1930,6 +1930,16 @@ void MacroAssembler::DebugBreak() {
   Call(ces.GetCode(), RelocInfo::DEBUGGER_STATEMENT);
 }
 
+void MacroAssembler::MaybeDropFrames() {
+  // Check whether we need to drop frames to restart a function on the stack.
+  ExternalReference restart_fp =
+      ExternalReference::debug_restart_fp_address(isolate());
+  mov(r1, Operand(restart_fp));
+  ldr(r1, MemOperand(r1));
+  tst(r1, r1);
+  Jump(isolate()->builtins()->FrameDropperTrampoline(), RelocInfo::CODE_TARGET,
+       ne);
+}
 
 void MacroAssembler::PushStackHandler() {
   // Adjust this code if not the case.