From 4fd8c327de7759aa987869a8933ef5a09a670b34 Mon Sep 17 00:00:00 2001
From: yurys <yurys@chromium.org>
Date: Tue, 29 Sep 2015 01:18:57 -0700
Subject: [PATCH] Tell MSAN that profiler doesn't expect sp to point at
 initialized memory

BUG=v8:4444,v8:4151
LOG=N

Review URL: https://codereview.chromium.org/1371253002

Cr-Commit-Position: refs/heads/master@{#30996}
---
 src/profiler/sampler.cc | 3 +++
 1 file changed, 3 insertions(+)

diff --git a/src/profiler/sampler.cc b/src/profiler/sampler.cc
index 8f01e4f..dc4c4c4 100644
--- a/src/profiler/sampler.cc
+++ b/src/profiler/sampler.cc
@@ -682,6 +682,9 @@ DISABLE_ASAN void TickSample::Init(Isolate* isolate,
     external_callback = scope->callback();
     has_external_callback = true;
   } else {
+    // sp register may point at an arbitrary place in memory, make
+    // sure MSAN doesn't complain about it.
+    MSAN_MEMORY_IS_INITIALIZED(regs.sp, sizeof(Address));
     // Sample potential return address value for frameless invocation of
     // stubs (we'll figure out later, if this value makes sense).
     tos = Memory::Address_at(reinterpret_cast<Address>(regs.sp));
-- 
2.7.4