Added Iterable, a class that vends standard C++

iterators for LLDB's container data structures.
Iterable abstracts over the backing data structure,
ignoring keys for maps for example.  It also provides
locking as a service so that the code

for (ThreadSP thread_sp : process->Threads())
{
  // ... use thread_sp
}

takes the appropriate locks once, without having to
do anything else.

The salient advantages of this system are:

- Much simpler and idiomatic loop code
- Lock once instead of each time an element is fetched
- Less boilerplate to produce the iterators

The intent is that Iterable will replace Get...AtIndex
in most places, and that ForEach(), which solves the
same problem in a less-idiomatic way, be phased out in
favor of this approach.

I've added Iterables to ThreadList, TypeList, and
Process (which is really just forwarding to ThreadList).

llvm-svn: 194159

1 files changed, 7 insertions, 8 deletions

diff --git a/lldb/source/Commands/CommandObjectThread.cpp b/lldb/source/Commands/CommandObjectThread.cpp
index f46a2219a50..3dce83c48d0 100644
--- a/lldb/source/Commands/CommandObjectThread.cpp
+++ b/lldb/source/Commands/CommandObjectThread.cpp
@@ -183,24 +183,23 @@ protected:
         else if (command.GetArgumentCount() == 1 && ::strcmp (command.GetArgumentAtIndex(0), "all") == 0)
         {
             Process *process = m_exe_ctx.GetProcessPtr();
-            Mutex::Locker locker (process->GetThreadList().GetMutex());
-            uint32_t num_threads = process->GetThreadList().GetSize();
-            for (uint32_t i = 0; i < num_threads; i++)
+            uint32_t idx = 0;
+            for (ThreadSP thread_sp : process->Threads())
             {
-                ThreadSP thread_sp = process->GetThreadList().GetThreadAtIndex(i);
+                if (idx != 0)
+                    result.AppendMessage("");
+
                 if (!thread_sp->GetStatus (strm,
                                            m_options.m_start,
                                            m_options.m_count,
                                            num_frames_with_source))
                 {
-                    result.AppendErrorWithFormat ("error displaying backtrace for thread: \"0x%4.4x\"\n", i);
+                    result.AppendErrorWithFormat ("error displaying backtrace for thread: \"0x%4.4x\"\n", idx);
                     result.SetStatus (eReturnStatusFailed);
                     return false;
                 }
                 
-                if (i < num_threads - 1)
-                    result.AppendMessage("");
-                    
+                ++idx;
             }
         }
         else