<rdar://problem/11672978> Fixing an issue where an ObjC object might come out without a description because the expression used to obtain it would timeout before running to completion

git-svn-id: https://llvm.org/svn/llvm-project/lldb/trunk@160326 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/source/Commands/CommandObjectExpression.cpp b/source/Commands/CommandObjectExpression.cpp
index 3c04eb3..4fecc6b 100644
--- a/source/Commands/CommandObjectExpression.cpp
+++ b/source/Commands/CommandObjectExpression.cpp
@@ -305,7 +305,8 @@
                                                   m_command_options.unwind_on_error,
                                                   keep_in_memory, 
                                                   use_dynamic, 
-                                                  result_valobj_sp);
+                                                  result_valobj_sp,
+                                                  0 /* no timeout */);
         
         if (exe_results == eExecutionInterrupted && !m_command_options.unwind_on_error)
         {
diff --git a/source/Commands/CommandObjectWatchpoint.cpp b/source/Commands/CommandObjectWatchpoint.cpp
index bb7ce45..973b9d4 100644
--- a/source/Commands/CommandObjectWatchpoint.cpp
+++ b/source/Commands/CommandObjectWatchpoint.cpp
@@ -1206,7 +1206,8 @@
                                                                    unwind_on_error, 
                                                                    keep_in_memory, 
                                                                    eNoDynamicValues, 
-                                                                   valobj_sp);
+                                                                   valobj_sp,
+                                                                   0 /* no timeout */);
         if (expr_result != eExecutionCompleted) {
             result.GetErrorStream().Printf("error: expression evaluation of address to watch failed\n");
             result.GetErrorStream().Printf("expression evaluated: %s\n", expr_str.c_str());
diff --git a/source/Expression/ClangUserExpression.cpp b/source/Expression/ClangUserExpression.cpp
index 4fed841..029b153 100644
--- a/source/Expression/ClangUserExpression.cpp
+++ b/source/Expression/ClangUserExpression.cpp
@@ -542,7 +542,8 @@
                               ExecutionContext &exe_ctx,
                               bool discard_on_error,
                               ClangUserExpression::ClangUserExpressionSP &shared_ptr_to_me,
-                              lldb::ClangExpressionVariableSP &result)
+                              lldb::ClangExpressionVariableSP &result,
+                              uint32_t single_thread_timeout_usec)
 {
     // The expression log is quite verbose, and if you're just tracking the execution of the
     // expression, it's quite convenient to have these logs come out with the STEP log as well.
@@ -578,8 +579,6 @@
     
         call_plan_sp->SetPrivate(true);
     
-        uint32_t single_thread_timeout_usec = 500000;
-        
         if (log)
             log->Printf("-- [ClangUserExpression::Execute] Execution of expression begins --");
         
@@ -648,10 +647,11 @@
                                bool discard_on_error,
                                const char *expr_cstr,
                                const char *expr_prefix,
-                               lldb::ValueObjectSP &result_valobj_sp)
+                               lldb::ValueObjectSP &result_valobj_sp,
+                               uint32_t single_thread_timeout_usec)
 {
     Error error;
-    return EvaluateWithError (exe_ctx, execution_policy, language, desired_type, discard_on_error, expr_cstr, expr_prefix, result_valobj_sp, error);
+    return EvaluateWithError (exe_ctx, execution_policy, language, desired_type, discard_on_error, expr_cstr, expr_prefix, result_valobj_sp, error, single_thread_timeout_usec);
 }
 
 ExecutionResults
@@ -663,7 +663,8 @@
                                         const char *expr_cstr,
                                         const char *expr_prefix,
                                         lldb::ValueObjectSP &result_valobj_sp,
-                                        Error &error)
+                                        Error &error,
+                                        uint32_t single_thread_timeout_usec)
 {
     lldb::LogSP log(lldb_private::GetLogIfAnyCategoriesSet (LIBLLDB_LOG_EXPRESSIONS | LIBLLDB_LOG_STEP));
 
@@ -738,7 +739,8 @@
                                                              exe_ctx, 
                                                              discard_on_error,
                                                              user_expression_sp, 
-                                                             expr_result);
+                                                             expr_result,
+                                                             single_thread_timeout_usec);
             
             if (execution_results != eExecutionCompleted)
             {
diff --git a/source/Interpreter/CommandInterpreter.cpp b/source/Interpreter/CommandInterpreter.cpp
index 2879ec4..b807e61 100644
--- a/source/Interpreter/CommandInterpreter.cpp
+++ b/source/Interpreter/CommandInterpreter.cpp
@@ -1162,7 +1162,8 @@
                                                                                unwind_on_error, 
                                                                                keep_in_memory, 
                                                                                eNoDynamicValues, 
-                                                                               expr_result_valobj_sp);
+                                                                               expr_result_valobj_sp,
+                                                                               0 /* no timeout */);
                     if (expr_result == eExecutionCompleted)
                     {
                         Scalar scalar;
diff --git a/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntime.cpp b/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntime.cpp
index a2bc888..4d001d8 100644
--- a/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntime.cpp
+++ b/source/Plugins/LanguageRuntime/ObjC/AppleObjCRuntime/AppleObjCRuntime.cpp
@@ -142,7 +142,7 @@
                                                      &wrapper_struct_addr, 
                                                      error_stream, 
                                                      stop_others, 
-                                                     100000, 
+                                                     0 /* no timeout */,
                                                      try_all_threads, 
                                                      unwind_on_error, 
                                                      ret);
diff --git a/source/Target/Process.cpp b/source/Target/Process.cpp
index 531b56c..61da768 100644
--- a/source/Target/Process.cpp
+++ b/source/Target/Process.cpp
@@ -4228,11 +4228,27 @@
                 
                 if (single_thread_timeout_usec != 0)
                 {
+                    // we have a > 0 timeout, let us set it so that we stop after the deadline
                     real_timeout = TimeValue::Now();
                     real_timeout.OffsetWithMicroSeconds(single_thread_timeout_usec);
                         
                     timeout_ptr = &real_timeout;
                 }
+                else if (first_timeout)
+                {
+                    // if we are willing to wait "forever" we still need to have an initial timeout
+                    // this timeout is going to induce all threads to run when hit. we do this so that
+                    // we can avoid ending locked up because of multithreaded contention issues
+                    real_timeout = TimeValue::Now();
+                    real_timeout.OffsetWithNanoSeconds(500000000UL);
+                    timeout_ptr = &real_timeout;
+                }
+                else
+                {
+                    timeout_ptr = NULL; // if we are in a no-timeout scenario, then we only need a fake timeout the first time through
+                    // at this point in the code, all threads will be running so we are willing to wait forever, and do not
+                    // need a timeout
+                }
             }
             else
             {
diff --git a/source/Target/StopInfo.cpp b/source/Target/StopInfo.cpp
index 5b782be..fe4f795 100644
--- a/source/Target/StopInfo.cpp
+++ b/source/Target/StopInfo.cpp
@@ -520,7 +520,8 @@
                                                                       wp_sp->GetConditionText(),
                                                                       NULL,
                                                                       result_value_sp,
-                                                                      error);
+                                                                      error,
+                                                                      500000);
                 if (result_code == eExecutionCompleted)
                 {
                     if (result_value_sp)
diff --git a/source/Target/Target.cpp b/source/Target/Target.cpp
index c5c0a18..5b56827 100644
--- a/source/Target/Target.cpp
+++ b/source/Target/Target.cpp
@@ -1652,7 +1652,8 @@
     bool unwind_on_error,
     bool keep_in_memory,
     lldb::DynamicValueType use_dynamic,
-    lldb::ValueObjectSP &result_valobj_sp
+    lldb::ValueObjectSP &result_valobj_sp,
+    uint32_t single_thread_timeout_usec
 )
 {
     ExecutionResults execution_results = eExecutionSetupError;
@@ -1781,7 +1782,8 @@
                                                                unwind_on_error,
                                                                expr_cstr, 
                                                                prefix, 
-                                                               result_valobj_sp);
+                                                               result_valobj_sp,
+                                                               single_thread_timeout_usec);
         }
     }