<rdar://problem/15960553>

Fix a bug where calling SBFrame::FindValue() would cause a copy of all variables in the block to be inserted in the frame's variable list, regardless of whether those same variables were there or not - which means one could end up with a frame with lots of duplicate copies of the same variables

llvm-svn: 201614

lldb/include/lldb/Symbol/VariableList.h

@@ -49,6 +49,9 @@ public:
     
     lldb::VariableSP
     FindVariable (const ConstString& name);
+    
+    lldb::VariableSP
+    FindVariable (const ConstString& name, lldb::ValueType value_type);
 
     uint32_t
     FindVariableIndex (const lldb::VariableSP &var_sp);

lldb/source/API/SBFrame.cpp

@@ -852,7 +852,7 @@ SBFrame::FindValue (const char *name, ValueType value_type, lldb::DynamicValueTy
                 case eValueTypeVariableArgument:    // function argument variables
                 case eValueTypeVariableLocal:       // function local variables
                     {
-                        VariableList *variable_list = frame->GetVariableList(true);
+                        VariableList variable_list;
 
                         SymbolContext sc (frame->GetSymbolContext (eSymbolContextBlock));
 
@@ -863,21 +863,15 @@ SBFrame::FindValue (const char *name, ValueType value_type, lldb::DynamicValueTy
                         if (sc.block && sc.block->AppendVariables (can_create, 
                                                                    get_parent_variables,
                                                                    stop_if_block_is_inlined_function,
-                                                                   variable_list))
+                                                                   &variable_list))
                         {
                             ConstString const_name(name);
-                            const uint32_t num_variables = variable_list->GetSize();
-                            for (uint32_t i = 0; i < num_variables; ++i)
+                            VariableSP variable_sp(variable_list.FindVariable(const_name,value_type));
+                            if (variable_sp)
                             {
-                                VariableSP variable_sp (variable_list->GetVariableAtIndex(i));
-                                if (variable_sp && 
-                                    variable_sp->GetScope() == value_type &&
-                                    variable_sp->GetName() == const_name)
-                                {
-                                    value_sp = frame->GetValueObjectForFrameVariable (variable_sp, eNoDynamicValues);
-                                    sb_value.SetSP (value_sp, use_dynamic);
-                                    break;
-                                }
+                                value_sp = frame->GetValueObjectForFrameVariable (variable_sp, eNoDynamicValues);
+                                sb_value.SetSP (value_sp, use_dynamic);
+                                break;
                             }
                         }
                     }

lldb/source/Symbol/VariableList.cpp

@@ -115,6 +115,22 @@ VariableList::FindVariable(const ConstString& name)
     return var_sp;
 }
 
+VariableSP
+VariableList::FindVariable (const ConstString& name, lldb::ValueType value_type)
+{
+    VariableSP var_sp;
+    iterator pos, end = m_variables.end();
+    for (pos = m_variables.begin(); pos != end; ++pos)
+    {
+        if ((*pos)->NameMatches(name) && (*pos)->GetScope() == value_type)
+        {
+            var_sp = (*pos);
+            break;
+        }
+    }
+    return var_sp;
+}
+
 size_t
 VariableList::AppendVariablesIfUnique (const RegularExpression& regex, VariableList &var_list, size_t& total_matches)
 {

lldb/test/python_api/findvalue_duplist/Makefile

@@ -0,0 +1,8 @@
+LEVEL = ../../make
+
+CXX_SOURCES := main.cpp
+
+# Clean renamed executable on 'make clean'
+clean: OBJECTS+=no_synth
+
+include $(LEVEL)/Makefile.rules

lldb/test/python_api/findvalue_duplist/TestSBFrameFindValue.py

@@ -0,0 +1,70 @@
+"""Test that SBFrame::FindValue finds things but does not duplicate the entire variables list"""
+
+import os, sys, time
+import unittest2
+import lldb
+from lldbtest import *
+import lldbutil
+
+class SBFrameFindValueTestCase(TestBase):
+
+    mydir = TestBase.compute_mydir(__file__)
+
+    @unittest2.skipUnless(sys.platform.startswith("darwin"), "requires Darwin")
+    @python_api_test
+    @dsym_test
+    def test_with_dsym_formatters_api(self):
+        """Test that SBFrame::FindValue finds things but does not duplicate the entire variables list"""
+        self.buildDsym()
+        self.setTearDownCleanup()
+        self.commands()
+
+    @python_api_test
+    @dwarf_test
+    def test_with_dwarf_formatters_api(self):
+        """Test that SBFrame::FindValue finds things but does not duplicate the entire variables list"""
+        self.buildDwarf()
+        self.setTearDownCleanup()
+        self.commands()
+
+    def setUp(self):
+        # Call super's setUp().
+        TestBase.setUp(self)
+
+    def commands(self):
+        """Test that SBFrame::FindValue finds things but does not duplicate the entire variables list"""
+        exe_name = "a.out"
+        exe = os.path.join(os.getcwd(), exe_name)
+
+        # Create the target
+        target = self.dbg.CreateTarget(exe)
+        self.assertTrue(target, VALID_TARGET)
+        
+        # Set the breakpoints
+        breakpoint = target.BreakpointCreateBySourceRegex('Set breakpoint here', lldb.SBFileSpec("main.cpp"))
+        self.assertTrue(breakpoint.GetNumLocations() > 0, VALID_BREAKPOINT)
+
+        # Launch the process, and do not stop at the entry point.
+        process = target.LaunchSimple(None, None, os.getcwd())
+
+        self.assertTrue(process, PROCESS_IS_VALID)
+
+        # Frame #0 should be at our breakpoint.
+        threads = lldbutil.get_threads_stopped_at_breakpoint (process, breakpoint)
+        
+        self.assertTrue(len(threads) == 1)
+        self.thread = threads[0]
+        self.frame = self.thread.frames[0]
+        self.assertTrue(self.frame, "Frame 0 is valid.")
+
+        self.assertTrue(self.frame.GetVariables(True,True,False,True).GetSize() == 2, "variable count is off")
+        self.assertFalse(self.frame.FindValue("NoSuchThing",lldb.eValueTypeVariableArgument,lldb.eDynamicCanRunTarget).IsValid(), "found something that should not be here")
+        self.assertTrue(self.frame.GetVariables(True,True,False,True).GetSize() == 2, "variable count is off after failed FindValue()")
+        self.assertTrue(self.frame.FindValue("a",lldb.eValueTypeVariableArgument,lldb.eDynamicCanRunTarget).IsValid(), "FindValue() didn't find an argument")
+        self.assertTrue(self.frame.GetVariables(True,True,False,True).GetSize() == 2, "variable count is off after successful FindValue()")
+
+if __name__ == '__main__':
+    import atexit
+    lldb.SBDebugger.Initialize()
+    atexit.register(lambda: lldb.SBDebugger.Terminate())
+    unittest2.main()

lldb/test/python_api/findvalue_duplist/main.cpp

@@ -0,0 +1,7 @@
+int foo(int a, int b) {
+	return a + b; // Set breakpoint here
+}
+
+int main() {
+	return foo(1,3);
+}