From ba827dfdaedffb20844c997abed43c02c3279a37 Mon Sep 17 00:00:00 2001
From: Dmitry Vyukov <dvyukov@google.com>
Date: Tue, 6 Nov 2012 13:16:25 +0000
Subject: [PATCH] tsan: don't release disabled clocks

llvm-svn: 167451
---
 compiler-rt/lib/tsan/rtl/tsan_clock.cc | 6 ++++++
 compiler-rt/lib/tsan/rtl/tsan_clock.h  | 3 ++-
 2 files changed, 8 insertions(+), 1 deletion(-)

diff --git a/compiler-rt/lib/tsan/rtl/tsan_clock.cc b/compiler-rt/lib/tsan/rtl/tsan_clock.cc
index 32ed91dc2103..89e788d27658 100644
--- a/compiler-rt/lib/tsan/rtl/tsan_clock.cc
+++ b/compiler-rt/lib/tsan/rtl/tsan_clock.cc
@@ -58,6 +58,7 @@ namespace __tsan {
 
 ThreadClock::ThreadClock() {
   nclk_ = 0;
+  disabled_ = false;
   for (uptr i = 0; i < (uptr)kMaxTidInClock; i++)
     clk_[i] = 0;
 }
@@ -80,6 +81,8 @@ void ThreadClock::release(SyncClock *dst) const {
   DCHECK(nclk_ <= kMaxTid);
   DCHECK(dst->clk_.Size() <= kMaxTid);
 
+  if (disabled_)
+    return;
   if (dst->clk_.Size() < nclk_)
     dst->clk_.Resize(nclk_);
   for (uptr i = 0; i < nclk_; i++) {
@@ -92,6 +95,8 @@ void ThreadClock::ReleaseStore(SyncClock *dst) const {
   DCHECK(nclk_ <= kMaxTid);
   DCHECK(dst->clk_.Size() <= kMaxTid);
 
+  if (disabled_)
+    return;
   if (dst->clk_.Size() < nclk_)
     dst->clk_.Resize(nclk_);
   for (uptr i = 0; i < nclk_; i++)
@@ -106,6 +111,7 @@ void ThreadClock::acq_rel(SyncClock *dst) {
 }
 
 void ThreadClock::Disable(unsigned tid) {
+  disabled_ = true;
   u64 c0 = clk_[tid];
   for (uptr i = 0; i < kMaxTidInClock; i++)
     clk_[i] = (u64)-1;
diff --git a/compiler-rt/lib/tsan/rtl/tsan_clock.h b/compiler-rt/lib/tsan/rtl/tsan_clock.h
index 02ddb9abdb30..38a99db9538d 100644
--- a/compiler-rt/lib/tsan/rtl/tsan_clock.h
+++ b/compiler-rt/lib/tsan/rtl/tsan_clock.h
@@ -48,7 +48,7 @@ struct ThreadClock {
 
   void set(unsigned tid, u64 v) {
     DCHECK_LT(tid, kMaxTid);
-    DCHECK_GE(v, clk_[tid]);
+    DCHECK(v >= clk_[tid] || disabled_);
     clk_[tid] = v;
     if (nclk_ <= tid)
       nclk_ = tid + 1;
@@ -74,6 +74,7 @@ struct ThreadClock {
 
  private:
   uptr nclk_;
+  bool disabled_;
   u64 clk_[kMaxTidInClock];
 };