From 4fe2302ae218217e52563d3f78183283960cd4bb Mon Sep 17 00:00:00 2001
From: Johnny Chen <johnny.chen@apple.com>
Date: Tue, 21 Aug 2012 23:17:04 +0000
Subject: [PATCH] Fix test failures in TestWatchpointIter.py due to
 http://llvm.org/viewvc/llvm-project?rev=162322&view=rev.

llvm-svn: 162328
---
 lldb/include/lldb/Breakpoint/Watchpoint.h |  9 +++++++++
 lldb/source/Breakpoint/Watchpoint.cpp     | 20 +++++++++++++++++++-
 lldb/source/Target/StopInfo.cpp           |  6 ++++++
 3 files changed, 34 insertions(+), 1 deletion(-)

diff --git a/lldb/include/lldb/Breakpoint/Watchpoint.h b/lldb/include/lldb/Breakpoint/Watchpoint.h
index 2b72a2fd4fe7..13a37041af4c 100644
--- a/lldb/include/lldb/Breakpoint/Watchpoint.h
+++ b/lldb/include/lldb/Breakpoint/Watchpoint.h
@@ -150,6 +150,12 @@ public:
     //------------------------------------------------------------------
     const char *GetConditionText () const;
 
+    void
+    TurnOnEphemeralMode();
+
+    void
+    TurnOffEphemeralMode();
+
 private:
     friend class Target;
     friend class WatchpointList;
@@ -161,6 +167,9 @@ private:
     bool        m_enabled;             // Is this watchpoint enabled
     bool        m_is_hardware;         // Is this a hardware watchpoint
     bool        m_is_watch_variable;   // True if set via 'watchpoint set variable'.
+    bool        m_is_ephemeral;        // True if the watchpoint is in the ephemeral mode, meaning that it is
+                                       // undergoing a pair of temporary disable/enable actions to avoid recursively
+                                       // triggering further watchpoint events.
     uint32_t    m_watch_read:1,        // 1 if we stop when the watched data is read from
                 m_watch_write:1,       // 1 if we stop when the watched data is written to
                 m_watch_was_read:1,    // Set to 1 when watchpoint is hit for a read access
diff --git a/lldb/source/Breakpoint/Watchpoint.cpp b/lldb/source/Breakpoint/Watchpoint.cpp
index 7c048fadf4a7..3736adb3b730 100644
--- a/lldb/source/Breakpoint/Watchpoint.cpp
+++ b/lldb/source/Breakpoint/Watchpoint.cpp
@@ -29,6 +29,7 @@ Watchpoint::Watchpoint (lldb::addr_t addr, size_t size, bool hardware) :
     m_enabled(false),
     m_is_hardware(hardware),
     m_is_watch_variable(false),
+    m_is_ephemeral(false),
     m_watch_read(0),
     m_watch_write(0),
     m_watch_was_read(0),
@@ -307,12 +308,29 @@ Watchpoint::IsEnabled() const
     return m_enabled;
 }
 
+// Within StopInfo.cpp, we purposely turn on the ephemeral mode right before temporarily disable the watchpoint
+// in order to perform possible watchpoint actions without triggering further watchpoint events.
+// After the temporary disabled watchpoint is enabled, we then turn off the ephemeral mode.
+
+void
+Watchpoint::TurnOnEphemeralMode()
+{
+    m_is_ephemeral = true;
+}
+
+void
+Watchpoint::TurnOffEphemeralMode()
+{
+    m_is_ephemeral = false;
+}
+
 void
 Watchpoint::SetEnabled(bool enabled)
 {
     if (!enabled)
     {
-        SetHardwareIndex(LLDB_INVALID_INDEX32);
+        if (!m_is_ephemeral)
+            SetHardwareIndex(LLDB_INVALID_INDEX32);
         // Don't clear the snapshots for now.
         // Within StopInfo.cpp, we purposely do disable/enable watchpoint while performing watchpoint actions.
         //ClearSnapshots();
diff --git a/lldb/source/Target/StopInfo.cpp b/lldb/source/Target/StopInfo.cpp
index 2d48dccaca48..400829ff7824 100644
--- a/lldb/source/Target/StopInfo.cpp
+++ b/lldb/source/Target/StopInfo.cpp
@@ -454,12 +454,18 @@ public:
             watchpoint(w)
         {
             if (process && watchpoint)
+            {
+                watchpoint->TurnOnEphemeralMode();
                 process->DisableWatchpoint(watchpoint);
+            }
         }
         ~WatchpointSentry()
         {
             if (process && watchpoint)
+            {
                 process->EnableWatchpoint(watchpoint);
+                watchpoint->TurnOffEphemeralMode();
+            }
         }
     private:
         Process *process;