[lldb] Don't filter variable list when doing a lookup by mangled name in SymbolFileDWARF::FindGlobalVariables

[labath]

A test case?

[kubamracek]

Adding a test case.

[jingham]

One picky comment about the test, otherwise this looks good to me. Pavel had his hands in this code most recently, however, so we should wait on his opinion.

packages/Python/lldbsuite/test/lang/cpp/global_variables/TestGlobalVariables.py

32–42

Can you use lldbutil.run_to_source_breakpoint to do this? Like:

lldbutil.run_to_source_breakpoint(self, "//Set break point at this line", self.source)

[kubamracek]

Updating test to use run_to_source_breakpoint

[labath]

Thanks for adding the test.

I guess I've touched this bit when I was working on the dwarf5 index thingy, but all my memory of this function has already been swapped out (and I'm not sure I ever fully understood all the nuances of how it was supposed to work).

So yeah, I think this is fine but I don't feel very qualified to make that claim.

packages/Python/lldbsuite/test/lang/cpp/global_variables/TestGlobalVariables.py

20

I don't think this bug applies here, as we're inspecting a running process, though we don't have any arm64 bots running ATM to verify that. I'd just remove this XFAIL.

[kubamracek]

Okay. @jingham, any more comments, or is this okay to land?

[jingham]

LGTM

packages/Python/lldbsuite/test/lang/cpp/global_variables/Makefile

+LEVEL = ../../../make
+
+CXX_SOURCES := main.cpp
+
+include $(LEVEL)/Makefile.rules

packages/Python/lldbsuite/test/lang/cpp/global_variables/TestGlobalVariables.py

+"""Test that C++ global variables can be inspected by name and also their mangled name."""
+
+from __future__ import print_function
+
+
+from lldbsuite.test.decorators import *
+from lldbsuite.test.lldbtest import *
+from lldbsuite.test import lldbutil
+
+
+class GlobalVariablesCppTestCase(TestBase):
+
+    mydir = TestBase.compute_mydir(__file__)
+
+    def setUp(self):
+        TestBase.setUp(self)
+        self.source = lldb.SBFileSpec('main.cpp')
+
+    @expectedFailureAll(oslist=["windows"], bugnumber="llvm.org/pr24764")
+    @expectedFailureAll(oslist=["linux"], archs=["aarch64"], bugnumber="llvm.org/pr37301")
+    def test(self):
+        self.build()
+
+        (target, _, _, _) = lldbutil.run_to_source_breakpoint(self, "// Set break point at this line.", self.source)
+        
+        # Check that we can access g_file_global_int by its name
+        self.expect("target variable g_file_global_int", VARIABLES_DISPLAYED_CORRECTLY,
+                    substrs=['42'])
+        self.expect("target variable abc::g_file_global_int", VARIABLES_DISPLAYED_CORRECTLY,
+                    substrs=['42'])
+        self.expect("target variable xyz::g_file_global_int", VARIABLES_DISPLAYED_CORRECTLY,
+                    error=True, substrs=['can\'t find global variable'])
+
+        # Check that we can access g_file_global_int by its mangled name
+        addr = target.EvaluateExpression("&abc::g_file_global_int").GetValueAsUnsigned()
+        self.assertTrue(addr != 0)
+        mangled = lldb.SBAddress(addr, target).GetSymbol().GetMangledName()
+        self.assertTrue(mangled != None)
+        gv = target.FindFirstGlobalVariable(mangled)
+        self.assertTrue(gv.IsValid())
+        self.assertEqual(gv.GetName(), "abc::g_file_global_int")
+        self.assertEqual(gv.GetValueAsUnsigned(), 42)

packages/Python/lldbsuite/test/lang/cpp/global_variables/main.cpp

+//===-- main.c --------------------------------------------------*- C++ -*-===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+#include <stdio.h>
+
+namespace abc {
+  int g_file_global_int = 42;
+}
+
+int main (int argc, char const *argv[])
+{
+    return abc::g_file_global_int; // Set break point at this line.
+}

source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp

uint32_t SymbolFileDWARF::FindGlobalVariables(
   if (info == NULL)
     return 0;
 
   // Remember how many variables are in the list before we search.
   const uint32_t original_size = variables.GetSize();
 
   llvm::StringRef basename;
   llvm::StringRef context;
+  bool name_is_mangled = (bool)Mangled(name);
 
   if (!CPlusPlusLanguage::ExtractContextAndIdentifier(name.GetCString(),
                                                       context, basename))
     basename = name.GetStringRef();
 
   DIEArray die_offsets;
   m_index->GetGlobalVariables(ConstString(basename), die_offsets);
   const size_t num_die_matches = die_offsets.size();
for (size_t i = 0; i < num_die_matches && !done; ++i) {
                 continue;
             }
           }
 
           ParseVariables(sc, die, LLDB_INVALID_ADDRESS, false, false,
                          &variables);
           while (pruned_idx < variables.GetSize()) {
             VariableSP var_sp = variables.GetVariableAtIndex(pruned_idx);
-            if (var_sp->GetName().GetStringRef().contains(name.GetStringRef()))
+            if (name_is_mangled ||
+                var_sp->GetName().GetStringRef().contains(name.GetStringRef()))
               ++pruned_idx;
             else
               variables.RemoveVariableAtIndex(pruned_idx);
           }
 
           if (variables.GetSize() - original_size >= max_matches)
             done = true;
         } break;