MemorySanitizer support.

runtime/vm/profiler.cc

 // Copyright (c) 2013, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
+#include "platform/memory_sanitizer.h"
 #include "platform/utils.h"
 
 #include "vm/allocation.h"
 #include "vm/atomic.h"
 #include "vm/code_patcher.h"
 #include "vm/isolate.h"
 #include "vm/json_stream.h"
 #include "vm/lockers.h"
 #include "vm/native_symbol.h"
 #include "vm/object.h"
@@ skipping 1912 matching lines @@
   }
 
  private:
   uword* CallerPC(uword* fp) const {
     ASSERT(fp != NULL);
     return reinterpret_cast<uword*>(*(fp + kSavedCallerPcSlotFromFp));
   }
 
   uword* CallerFP(uword* fp) const {
     ASSERT(fp != NULL);
-    return reinterpret_cast<uword*>(*(fp + kSavedCallerFpSlotFromFp));
+    uword* caller_fp_ptr = fp + kSavedCallerFpSlotFromFp;
+    // This may actually be uninitialized, by design (see class comment above).
+    __msan_unpoison(caller_fp_ptr, kWordSize);
+    return reinterpret_cast<uword*>(*caller_fp_ptr);
   }
 
   bool ValidFramePointer(uword* fp) const {
     if (fp == NULL) {
       return false;
     }
     uword cursor = reinterpret_cast<uword>(fp);
     cursor += sizeof(fp);
     bool r = (cursor >= lower_bound_) && (cursor < stack_upper_);
     return r;
@@ skipping 162 matching lines @@
                                             state.pc,
                                             state.fp,
                                             sp);
       stackWalker.walk();
 #endif
     }
   }
 }
 
 }  // namespace dart