PPC/s390: [liveedit] reimplement frame restarting.

src/s390/macro-assembler-s390.cc

Index: src/s390/macro-assembler-s390.cc
diff --git a/src/s390/macro-assembler-s390.cc b/src/s390/macro-assembler-s390.cc
index 4ed7c19002326a6c0031198da2f020fb164e02aa..dfc11a07715757c8facfaffa5d2f8e1c6f150c3d 100644
--- a/src/s390/macro-assembler-s390.cc
+++ b/src/s390/macro-assembler-s390.cc
@@ -1472,6 +1472,17 @@ 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(r3, Operand(restart_fp));
+  LoadP(r3, MemOperand(r3));
+  CmpP(r3, Operand::Zero());
+  Jump(isolate()->builtins()->FrameDropperTrampoline(), RelocInfo::CODE_TARGET,
+       ne);
+}
+
 void MacroAssembler::PushStackHandler() {
   // Adjust this code if not the case.
   STATIC_ASSERT(StackHandlerConstants::kSize == 1 * kPointerSize);