2 files changed, 26 insertions, 0 deletions
diff --git a/llvm/include/llvm/Support/PrettyStackTrace.h b/llvm/include/llvm/Support/PrettyStackTrace.h
index 96afb60d8e5..027f9433969 100644
--- a/llvm/include/llvm/Support/PrettyStackTrace.h
+++ b/llvm/include/llvm/Support/PrettyStackTrace.h
@@ -66,6 +66,18 @@ namespace llvm {
     void print(raw_ostream &OS) const override;
   };
 
+  /// Returns the topmost element of the "pretty" stack state.
+  const void* SavePrettyStackState();
+
+  /// Restores the topmost element of the "pretty" stack state to State, which
+  /// should come from a previous call to SavePrettyStackState().  This is
+  /// useful when using a CrashRecoveryContext in code that also uses
+  /// PrettyStackTraceEntries, to make sure the stack that's printed if a crash
+  /// happens after a crash that's been recovered by CrashRecoveryContext
+  /// doesn't have frames on it that were added in code unwound by the
+  /// CrashRecoveryContext.
+  void RestorePrettyStackState(const void* State);
+
 } // end namespace llvm
 
 #endif
diff --git a/llvm/lib/Support/PrettyStackTrace.cpp b/llvm/lib/Support/PrettyStackTrace.cpp
index f9f8cab9d93..d6782a70e1a 100644
--- a/llvm/lib/Support/PrettyStackTrace.cpp
+++ b/llvm/lib/Support/PrettyStackTrace.cpp
@@ -154,6 +154,20 @@ void llvm::EnablePrettyStackTrace() {
 #endif
 }
 
+const void* llvm::SavePrettyStackState() {
+#if defined(HAVE_BACKTRACE) && defined(ENABLE_BACKTRACES)
+  return PrettyStackTraceHead;
+#else
+  return nullptr;
+#endif
+}
+
+void llvm::RestorePrettyStackState(const void* Top) {
+#if defined(HAVE_BACKTRACE) && defined(ENABLE_BACKTRACES)
+  PrettyStackTraceHead = (const PrettyStackTraceEntry*)Top;
+#endif
+}
+
 void LLVMEnablePrettyStackTrace() {
   EnablePrettyStackTrace();
 }