libsanitizer merge from upstream r191666

This may break gcc-asan on Mac, will follow up separately.



git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@204368 138bc75d-0d04-0410-961f-82ee72b054a4

1 files changed, 26 insertions, 0 deletions

diff --git a/libsanitizer/sanitizer_common/sanitizer_stackdepot.h b/libsanitizer/sanitizer_common/sanitizer_stackdepot.h
index bf73cf14aad..c2c04ef9d64 100644
--- a/libsanitizer/sanitizer_common/sanitizer_stackdepot.h
+++ b/libsanitizer/sanitizer_common/sanitizer_stackdepot.h
@@ -11,6 +11,7 @@
 #ifndef SANITIZER_STACKDEPOT_H
 #define SANITIZER_STACKDEPOT_H
 
+#include "sanitizer_common.h"
 #include "sanitizer_internal_defs.h"
 
 namespace __sanitizer {
@@ -29,6 +30,31 @@ struct StackDepotStats {
 
 StackDepotStats *StackDepotGetStats();
 
+struct StackDesc;
+
+// Instantiating this class creates a snapshot of StackDepot which can be
+// efficiently queried with StackDepotGet(). You can use it concurrently with
+// StackDepot, but the snapshot is only guaranteed to contain those stack traces
+// which were stored before it was instantiated.
+class StackDepotReverseMap {
+ public:
+  StackDepotReverseMap();
+  const uptr *Get(u32 id, uptr *size);
+
+ private:
+  struct IdDescPair {
+    u32 id;
+    StackDesc *desc;
+
+    static bool IdComparator(const IdDescPair &a, const IdDescPair &b);
+  };
+
+  InternalMmapVector<IdDescPair> map_;
+
+  // Disallow evil constructors.
+  StackDepotReverseMap(const StackDepotReverseMap&);
+  void operator=(const StackDepotReverseMap&);
+};
 }  // namespace __sanitizer
 
 #endif  // SANITIZER_STACKDEPOT_H