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runtime/vm/signal_handler_linux.cc

Index: runtime/vm/signal_handler_linux.cc
diff --git a/runtime/vm/signal_handler_linux.cc b/runtime/vm/signal_handler_linux.cc
index 980733e2cd5279da200b2089772be9fceea36876..957edda62bc2b5b46b0d0d7e4651f6898a51b554 100644
--- a/runtime/vm/signal_handler_linux.cc
+++ b/runtime/vm/signal_handler_linux.cc
@@ -97,6 +97,32 @@ uintptr_t SignalHandler::GetDartStackPointer(const mcontext_t& mcontext) {
 }
 
 
+uintptr_t SignalHandler::GetLinkRegister(const mcontext_t& mcontext) {
+  uintptr_t lr = 0;
+
+#if defined(TARGET_ARCH_IA32)
+  lr = 0;
+#elif defined(TARGET_ARCH_X64)
+  lr = 0;
+#elif defined(TARGET_ARCH_MIPS) && defined(USING_SIMULATOR)
+  lr = 0;
+#elif defined(TARGET_ARCH_ARM) && defined(USING_SIMULATOR)
+  lr = 0;
+#elif defined(TARGET_ARCH_ARM64) && defined(USING_SIMULATOR)
+  lr = 0;
+#elif defined(TARGET_ARCH_ARM)
+  lr = static_cast<uintptr_t>(mcontext.arm_lr);
+#elif defined(TARGET_ARCH_ARM64)
+  lr = static_cast<uintptr_t>(mcontext.lr);
+#elif defined(TARGET_ARCH_MIPS)
+  lr = static_cast<uintptr_t>(mcontext.gregs[31]);
+#else
+  UNIMPLEMENTED();
+#endif  // TARGET_ARCH_...
+  return lr;
+}
+
+
 void SignalHandler::Install(SignalAction action) {
   struct sigaction act;
   act.sa_handler = NULL;