lldb-test symbols: Add ability to do name-based lookup

[labath]

Summary

lldb-test already had the ability to dump all symbol information in a
module. This is interesting, but it can be too verbose, and it also does
not use the same APIs that lldb uses to query symbol information. The
last part is interesting to me now, because I am about to add DWARF v5
debug_names support, which needs to implement these APIs.

This patch adds a set of arguments to lldb-test, which modify it's
behavior from dumping all symbols to dumping only the requested
information:

• --lookup={function,namespace,type,variable} - search for the given kind of objects.

• --name - the name to search for.

• --regex - whether to treat the "name" as a regular expression. This is not available for all lookup types (we do not have the required APIs for namespaces and types).

• --context - specifies the context, which can be used to restrict the search. This argument takes a variable name (which must be defined and be unique), and we then use the context that this variable is defined in as the search context.

• --function-flags={auto,full,base,method,selector} - a set of flags to further restrict the search for function symbols.

Together, these flags and their combinations cover the main SymbolFile
entry points which I will need to modify for the accelerator table
support, and so I plan to do most of the regression testing this way.
(I've also found this a useful tool for exploration of what the given
APIs are supposed to do.)

I add a couple of tests to demonstrate the usage of the usage of the
various options, and also an xfailed test which demonstrates a bug I
found while playing with this. The only requirement for these tests is
the presence of lld -- the should run on any platform which is able to
build lldb.

These tests use c++ code as input, but this isn't a requirement. It is also
possible to use IR, assembly or json to create the test module.

[zturner]

lit/CMakeLists.txt

32

Note that this depends on lld having had its own CMakeLists.txt file processed before LLDB's. I think this happens by accident since we process them in alphabetical order, but it's something to keep in mind.

lit/SymbolFile/DWARF/basic-function-lookup.cpp

23 ↗

(On Diff #144731)

I personally find it a little confusing to have the check lines interspersed with the source code here as we do in this file. I think it's easier to read if all check labels are grouped together so that you get a general idea of what the output of the tool looks like. I don't feel too strongly though, so up to you.

[JDevlieghere]

A few nits/stylistic comments

tools/lldb-test/lldb-test.cpp

87

It's a bit unfortunate that these argument names are different from the ones we have in dwarfdump. For instance, we use -lookup for addresses and -find for the accelerator tables. (https://llvm.org/docs/CommandGuide/llvm-dwarfdump.html)

Would you mind using the same names here?

245

Empty()?

261

You can use WithColor::error() from Support :-)

304

This feels a bit C89-like; personally I prefer to initialize my variables as close to their use as possible.

[labath]

Address review comments.

lit/SymbolFile/DWARF/basic-function-lookup.cpp

23 ↗

(On Diff #144731)

I agree it looks better when it's grouped. I did it this way originally, because the first tests I was writing were the variable & type tests, and there I used `@LINE` thingies to match the declarations (as the output stands now, the declaration line is the only sufficiently deterministic property I can use to distinguish two variables with the same name). I have regrouped the checks which don't depend on the line numbers.

tools/lldb-test/lldb-test.cpp

87

Hmm... I agree we should avoid confusion where possible. So using lookup is out.
How about renaming it to find. It's nice that it matches the underlying lldb functions, but it is also a bit inconsistent because llvm-dwarfdump uses it to search through the accelerator tables. However we don't have the distinction between searching using accelerator tables and not, and I don't think we will need it (the idea here was to make this search the same way that lldb would do).

The alternative is to rename this argument to something completely different (--search, --name-type, ...)

245

There isn't such a function, but having it sounds like a good idea, so I added one. :)

[JDevlieghere]

tools/lldb-test/lldb-test.cpp

87

Alright, find sounds okay.

261

I probably should've noticed this earlier, but since we return after all these errors maybe I'd be nice to have the function return an error? Doesn't have to be in this diff though.

463

If we can wrap this in a RAII object we could have this tool return a non-zero exit code in case of an error.

[labath]

More review feedback.

[labath]

tools/lldb-test/lldb-test.cpp

261

I've handled this a bit differently. Since this will be the same regex for each module we dump, I've done the validation up-front (next to the other checks), and changed this into an assertion.

463

Done. I've made the individual functions return an int, and had main forward that. The reason I am not having the functions return an Error or like is that the functions generally do the same thing over several inputs, and the errors that happen when processing one of the inputs should be printed next to that input and not deferred until the end. So, the functions just accumulate a flag saying whether they encountered any errors and then return that.

[JDevlieghere]

A few more nits but otherwise this LGTM.

tools/lldb-test/lldb-test.cpp

462

formatting

463

Alright, works for me!

464

WithColor:error()? :-)

include/lldb/Symbol/VariableList.h

public:
   size_t AppendVariablesWithScope(lldb::ValueType type, VariableList &var_list,
                                   bool if_unique = true);
 
   uint32_t FindIndexForVariable(Variable *variable);
 
   size_t MemorySize() const;
 
   size_t GetSize() const;
+  bool Empty() const { return m_variables.empty(); }
 
 protected:
   typedef std::vector<lldb::VariableSP> collection;
   typedef collection::iterator iterator;
   typedef collection::const_iterator const_iterator;
 
   collection m_variables;
 

lit/CMakeLists.txt

 
 if (NOT LLDB_TEST_USE_CUSTOM_CXX_COMPILER)
   string(REPLACE ${CMAKE_CFG_INTDIR} ${LLVM_BUILD_MODE} LLDB_TEST_CXX_COMPILER ${LLDB_TEST_CXX_COMPILER})
 endif ()
 
 string(REPLACE ${CMAKE_CFG_INTDIR} ${LLVM_BUILD_MODE} LLDB_LIBS_DIR ${LLVM_LIBRARY_OUTPUT_INTDIR})
 string(REPLACE ${CMAKE_CFG_INTDIR} ${LLVM_BUILD_MODE} LLDB_TOOLS_DIR ${LLVM_RUNTIME_OUTPUT_INTDIR})
 
+set(LLDB_TEST_DEPS
+  LLDBUnitTests
+  dsymutil
+  lldb
+  lldb-test
+  llvm-config
+  llvm-mc
+  llvm-objcopy
+  )
+
+if(TARGET lld)
+  list(APPEND LLDB_TEST_DEPS lld)
+  set(LLDB_HAVE_LLD 1)
+else()
+  set(LLDB_HAVE_LLD 0)
+endif()
+
+
 if(BUILD_SHARED_LIBS)
   set(ENABLE_SHARED 1)
 else()
   set(ENABLE_SHARED 0)
 endif(BUILD_SHARED_LIBS)
 
 # the value is not canonicalized within LLVM
 llvm_canonicalize_cmake_booleans(
   LLVM_ENABLE_ZLIB)
 
 configure_lit_site_cfg(
   ${CMAKE_CURRENT_SOURCE_DIR}/lit.site.cfg.in
   ${CMAKE_CURRENT_BINARY_DIR}/lit.site.cfg)
 configure_lit_site_cfg(
   ${CMAKE_CURRENT_SOURCE_DIR}/Unit/lit.site.cfg.in
   ${CMAKE_CURRENT_BINARY_DIR}/Unit/lit.site.cfg
   )
 
-set(LLDB_TEST_DEPS
-  LLDBUnitTests
-  dsymutil
-  lldb
-  lldb-test
-  llvm-config
-  llvm-mc
-  llvm-objcopy
-  )
-
 if(NOT LLDB_BUILT_STANDALONE)
   list(APPEND LLDB_TEST_DEPS FileCheck not yaml2obj)
 endif()
   
 # lldb-server is not built on every platform.
 if (TARGET lldb-server)
   list(APPEND LLDB_TEST_DEPS lldb-server)
 endif()

lit/SymbolFile/DWARF/find-basic-function.cpp

+// REQUIRES: lld
+
+// RUN: clang %s -g -c -o %t.o --target=x86_64-pc-linux
+// RUN: ld.lld %t.o -o %t
+// RUN: lldb-test symbols --name=foo --find=function --function-flags=base %t | \
+// RUN:   FileCheck --check-prefix=BASE %s
+// RUN: lldb-test symbols --name=foo --find=function --function-flags=method %t | \
+// RUN:   FileCheck --check-prefix=METHOD %s
+// RUN: lldb-test symbols --name=foo --find=function --function-flags=full %t | \
+// RUN:   FileCheck --check-prefix=FULL %s
+// RUN: lldb-test symbols --name=foo --context=context --find=function --function-flags=base %t | \
+// RUN:   FileCheck --check-prefix=CONTEXT %s
+// RUN: lldb-test symbols --name=not_there --find=function %t | \
+// RUN:   FileCheck --check-prefix=EMPTY %s
+
+// BASE: Found 4 functions:
+// BASE-DAG: name = "foo()", mangled = "_Z3foov"
+// BASE-DAG: name = "foo(int)", mangled = "_Z3fooi"
+// BASE-DAG: name = "bar::foo()", mangled = "_ZN3bar3fooEv"
+// BASE-DAG: name = "bar::baz::foo()", mangled = "_ZN3bar3baz3fooEv"
+
+// METHOD: Found 3 functions:
+// METHOD-DAG: name = "sbar::foo()", mangled = "_ZN4sbar3fooEv"
+// METHOD-DAG: name = "sbar::foo(int)", mangled = "_ZN4sbar3fooEi"
+// METHOD-DAG: name = "ffbar()::sbar::foo()", mangled = "_ZZ5ffbarvEN4sbar3fooEv"
+
+// FULL: Found 2 functions:
+// FULL-DAG: name = "foo()", mangled = "_Z3foov"
+// FULL-DAG: name = "foo(int)", mangled = "_Z3fooi"
+
+// CONTEXT: Found 1 functions:
+// CONTEXT-DAG: name = "bar::foo()", mangled = "_ZN3bar3fooEv"
+
+// EMPTY: Found 0 functions:
+
+void foo() {}
+void foo(int) {}
+
+namespace bar {
+int context;
+void foo() {}
+namespace baz {
+void foo() {}
+} // namespace baz
+} // namespace bar
+
+struct foo {};
+void fbar(struct foo) {}
+
+void Foo() {}
+
+struct sbar {
+  void foo();
+  static void foo(int);
+};
+void sbar::foo() {}
+void sbar::foo(int) {}
+
+void ffbar() {
+  struct sbar {
+    void foo() {}
+  };
+  sbar a;
+  a.foo();
+}
+
+extern "C" void _start() {}

lit/SymbolFile/DWARF/find-basic-namespace.cpp

+// REQUIRES: lld
+
+// RUN: clang %s -g -c -o %t.o --target=x86_64-pc-linux
+// RUN: ld.lld %t.o -o %t
+// RUN: lldb-test symbols --name=foo --find=namespace %t | \
+// RUN:   FileCheck --check-prefix=FOO %s
+// RUN: lldb-test symbols --name=foo --find=namespace --context=context %t | \
+// RUN:   FileCheck --check-prefix=CONTEXT %s
+// RUN: lldb-test symbols --name=not_there --find=namespace %t | \
+// RUN:   FileCheck --check-prefix=EMPTY %s
+
+// FOO: Found namespace: foo
+
+// CONTEXT: Found namespace: bar::foo
+
+// EMPTY: Namespace not found.
+
+namespace foo {
+int X;
+}
+
+namespace bar {
+int context;
+namespace foo {
+int X;
+}
+} // namespace bar
+
+extern "C" void _start() {}

lit/SymbolFile/DWARF/find-basic-type.cpp

+// REQUIRES: lld
+
+// RUN: clang %s -g -c -o %t.o --target=x86_64-pc-linux
+// RUN: ld.lld %t.o -o %t
+// RUN: lldb-test symbols --name=foo --find=type %t | \
+// RUN:   FileCheck --check-prefix=NAME %s
+// RUN: lldb-test symbols --name=foo --context=context --find=type %t | \
+// RUN:   FileCheck --check-prefix=CONTEXT %s
+// RUN: lldb-test symbols --name=not_there --find=type %t | \
+// RUN:   FileCheck --check-prefix=EMPTY %s
+
+// EMPTY: Found 0 types:
+// NAME: Found 4 types:
+// CONTEXT: Found 1 types:
+struct foo { };
+// NAME-DAG: name = "foo", {{.*}} decl = find-basic-type.cpp:[[@LINE-1]]
+
+namespace bar {
+int context;
+struct foo {};
+// NAME-DAG: name = "foo", {{.*}} decl = find-basic-type.cpp:[[@LINE-1]]
+// CONTEXT-DAG: name = "foo", {{.*}} decl = find-basic-type.cpp:[[@LINE-2]]
+namespace baz {
+struct foo {};
+// NAME-DAG: name = "foo", {{.*}} decl = find-basic-type.cpp:[[@LINE-1]]
+}
+}
+
+struct sbar {
+  struct foo {};
+// NAME-DAG: name = "foo", {{.*}} decl = find-basic-type.cpp:[[@LINE-1]]
+};
+
+struct foobar {};
+
+struct Foo {};
+
+extern "C" void _start(foo, bar::foo, bar::baz::foo, sbar::foo, foobar, Foo) {}

lit/SymbolFile/DWARF/find-basic-variable.cpp

+// REQUIRES: lld
+
+// RUN: clang %s -g -c -o %t.o --target=x86_64-pc-linux
+// RUN: ld.lld %t.o -o %t
+// RUN: lldb-test symbols --name=foo --find=variable --context=context %t | \
+// RUN:   FileCheck --check-prefix=CONTEXT %s
+// RUN: lldb-test symbols --name=foo --find=variable %t | \
+// RUN:   FileCheck --check-prefix=NAME %s
+// RUN: lldb-test symbols --regex --name=foo --find=variable %t | \
+// RUN:   FileCheck --check-prefix=REGEX %s
+// RUN: lldb-test symbols --name=not_there --find=variable %t | \
+// RUN:   FileCheck --check-prefix=EMPTY %s
+
+// EMPTY: Found 0 variables:
+// NAME: Found 4 variables:
+// CONTEXT: Found 1 variables:
+// REGEX: Found 5 variables:
+int foo;
+// NAME-DAG: name = "foo", type = {{.*}} (int), {{.*}} decl = find-basic-variable.cpp:[[@LINE-1]]
+// REGEX-DAG: name = "foo", type = {{.*}} (int), {{.*}} decl = find-basic-variable.cpp:[[@LINE-2]]
+namespace bar {
+int context;
+long foo;
+// NAME-DAG: name = "foo", type = {{.*}} (long int), {{.*}} decl = find-basic-variable.cpp:[[@LINE-1]]
+// CONTEXT-DAG: name = "foo", type = {{.*}} (long int), {{.*}} decl = find-basic-variable.cpp:[[@LINE-2]]
+// REGEX-DAG: name = "foo", type = {{.*}} (long int), {{.*}} decl = find-basic-variable.cpp:[[@LINE-3]]
+namespace baz {
+static short foo;
+// NAME-DAG: name = "foo", type = {{.*}} (short), {{.*}} decl = find-basic-variable.cpp:[[@LINE-1]]
+// REGEX-DAG: name = "foo", type = {{.*}} (short), {{.*}} decl = find-basic-variable.cpp:[[@LINE-2]]
+}
+}
+
+struct sbar {
+  static int foo;
+// NAME-DAG: name = "foo", type = {{.*}} (int), {{.*}} decl = find-basic-variable.cpp:[[@LINE-1]]
+// REGEX-DAG: name = "foo", type = {{.*}} (int), {{.*}} decl = find-basic-variable.cpp:[[@LINE-2]]
+};
+int sbar::foo;
+
+int foobar;
+// REGEX-DAG: name = "foobar", type = {{.*}} (int), {{.*}} decl = find-basic-variable.cpp:[[@LINE-1]]
+
+int fbar() {
+  static int foo;
+  return foo + bar::baz::foo;
+}
+
+int Foo;
+
+struct ssbar {
+  int foo;
+};
+
+extern "C" void _start(sbar, ssbar) {}

lit/SymbolFile/DWARF/find-type-in-function.cpp

+// REQUIRES: lld
+
+// XFAIL: *
+
+// RUN: clang %s -g -c -o %t.o --target=x86_64-pc-linux
+// RUN: ld.lld %t.o -o %t
+// RUN: lldb-test symbols --name=foo --find=type %t | \
+// RUN:   FileCheck --check-prefix=NAME %s
+
+// Lookup for "foo" should find either both "struct foo" types or just the
+// global one. Right now, it finds the definition inside bar(), which is
+// definitely wrong.
+
+// NAME: Found 2 types:
+struct foo {};
+// NAME-DAG: name = "foo", {{.*}} decl = find-type-in-function.cpp:[[@LINE-1]]
+
+void bar() {
+  struct foo {};
+// NAME-DAG: name = "foo", {{.*}} decl = find-type-in-function.cpp:[[@LINE-1]]
+  foo a;
+}
+
+extern "C" void _start(foo) {}

lit/SymbolFile/DWARF/lit.local.cfg

+config.suffixes = ['.cpp']

lit/lit.cfg

 elif re.match(r'clang', config.cc):
     config.available_features.add("compiler-clang")
 elif re.match(r'gcc', config.cc):
     config.available_features.add("compiler-gcc")
 elif re.match(r'cl', config.cc):
     config.available_features.add("compiler-msvc")
 
 config.available_features.add(binary_feature(config.have_zlib, "zlib", "no"))
+if config.have_lld:
+  config.available_features.add("lld")
 
 # llvm-config knows whether it is compiled with asserts (and)
 # whether we are operating in release/debug mode.
 import subprocess
 try:
     llvm_config_cmd = \
      subprocess.Popen([os.path.join(llvm_tools_dir, 'llvm-config'),
                      '--build-mode', '--assertion-mode', '--targets-built'],

lit/lit.site.cfg.in

 @LIT_SITE_CFG_IN_HEADER@
 
 config.llvm_src_root = "@LLVM_SOURCE_DIR@"
 config.llvm_obj_root = "@LLVM_BINARY_DIR@"
 config.llvm_tools_dir = "@LLVM_TOOLS_DIR@"
 config.llvm_libs_dir = "@LLVM_LIBS_DIR@"
 config.lit_tools_dir = "@LLVM_LIT_TOOLS_DIR@"
 config.lldb_obj_root = "@LLDB_BINARY_DIR@"
 config.lldb_libs_dir = "@LLDB_LIBS_DIR@"
 config.lldb_tools_dir = "@LLDB_TOOLS_DIR@"
 config.target_triple = "@TARGET_TRIPLE@"
 config.python_executable = "@PYTHON_EXECUTABLE@"
 config.cc = "@LLDB_TEST_C_COMPILER@"
 config.cxx = "@LLDB_TEST_CXX_COMPILER@"
 config.have_zlib = @LLVM_ENABLE_ZLIB@
+config.have_lld = @LLDB_HAVE_LLD@
 
 # Support substitution of the tools and libs dirs with user parameters. This is
 # used when we can't determine the tool dir at configuration time.
 try:
     config.llvm_tools_dir = config.llvm_tools_dir % lit_config.params
     config.llvm_libs_dir = config.llvm_libs_dir % lit_config.params
     config.lldb_libs_dir = config.lldb_libs_dir % lit_config.params
     config.lldb_tools_dir = config.lldb_tools_dir % lit_config.params
     config.cc = config.cc % lit_config.params
     config.cxx = config.cxx % lit_config.params
 except KeyError as e:
     key, = e.args
     lit_config.fatal("unable to find %r parameter, use '--param=%s=VALUE'" % (key,key))
 
 # Let the main config do the real work.
 lit_config.load_config(config, "@LLDB_SOURCE_DIR@/lit/lit.cfg")

tools/lldb-test/lldb-test.cpp

 #include "lldb/Core/Debugger.h"
 #include "lldb/Core/Module.h"
 #include "lldb/Core/Section.h"
 #include "lldb/Initialization/SystemLifetimeManager.h"
 #include "lldb/Interpreter/CommandInterpreter.h"
 #include "lldb/Interpreter/CommandReturnObject.h"
 #include "lldb/Symbol/ClangASTContext.h"
 #include "lldb/Symbol/ClangASTImporter.h"
+#include "lldb/Symbol/SymbolVendor.h"
+#include "lldb/Symbol/TypeList.h"
+#include "lldb/Symbol/VariableList.h"
 #include "lldb/Utility/DataExtractor.h"
 #include "lldb/Utility/StreamString.h"
 
 #include "llvm/ADT/StringRef.h"
 #include "llvm/Support/CommandLine.h"
 #include "llvm/Support/ManagedStatic.h"
 #include "llvm/Support/Path.h"
 #include "llvm/Support/PrettyStackTrace.h"
 #include "llvm/Support/Signals.h"
+#include "llvm/Support/WithColor.h"
 #include <thread>
 
 using namespace lldb;
 using namespace lldb_private;
 using namespace llvm;
 
 namespace opts {
 static cl::SubCommand BreakpointSubcommand("breakpoints",

 cl::opt<bool> SectionContents("contents",
                               cl::desc("Dump each section's contents"),
                               cl::sub(ModuleSubcommand));
 cl::list<std::string> InputFilenames(cl::Positional, cl::desc("<input files>"),
                                      cl::OneOrMore, cl::sub(ModuleSubcommand));
 } // namespace module
 
 namespace symbols {
-cl::list<std::string> InputFilenames(cl::Positional, cl::desc("<input files>"),
-                                     cl::OneOrMore, cl::sub(SymbolsSubcommand));
+static cl::list<std::string> InputFilenames(cl::Positional,
+                                            cl::desc("<input files>"),
+                                            cl::OneOrMore,
+                                            cl::sub(SymbolsSubcommand));
+enum class FindType {
+  None,
+  Function,
+  Namespace,
+  Type,
+  Variable,
+};
+static cl::opt<FindType> Find(
+    "find", cl::desc("Choose search type:"),
+    cl::values(
+        clEnumValN(FindType::None, "none",
+                   "No search, just dump the module."),
+        clEnumValN(FindType::Function, "function", "Find functions."),
+        clEnumValN(FindType::Namespace, "namespace", "Find namespaces."),
+        clEnumValN(FindType::Type, "type", "Find types."),
+        clEnumValN(FindType::Variable, "variable", "Find global variables.")),
+    cl::sub(SymbolsSubcommand));
+
+static cl::opt<std::string> Name("name", cl::desc("Name to find."),
+                                 cl::sub(SymbolsSubcommand));
+static cl::opt<bool>
+    Regex("regex",
+          cl::desc("Search using regular expressions (avaliable for variables "
+                   "and functions only)."),
+          cl::sub(SymbolsSubcommand));
+static cl::opt<std::string>
+    Context("context",
+            cl::desc("Restrict search to the context of the given variable."),
+            cl::value_desc("variable"), cl::sub(SymbolsSubcommand));
+
+static cl::list<FunctionNameType> FunctionNameFlags(
+    "function-flags", cl::desc("Function search flags:"),
+    cl::values(clEnumValN(eFunctionNameTypeAuto, "auto",
+                          "Automatically deduce flags based on name."),
+               clEnumValN(eFunctionNameTypeFull, "full", "Full function name."),
+               clEnumValN(eFunctionNameTypeBase, "base", "Base name."),
+               clEnumValN(eFunctionNameTypeMethod, "method", "Method name."),
+               clEnumValN(eFunctionNameTypeSelector, "selector",
+                          "Selector name.")),
+    cl::sub(SymbolsSubcommand));
+static FunctionNameType getFunctionNameFlags() {
+  FunctionNameType Result = FunctionNameType(0);
+  for (FunctionNameType Flag : FunctionNameFlags)
+    Result = FunctionNameType(Result | Flag);
+  return Result;
+}
+
+static Expected<CompilerDeclContext> getDeclContext(SymbolVendor &Vendor);
+
+static void findFunctions(SymbolVendor &Vendor);
+static void findNamespaces(SymbolVendor &Vendor);
+static void findTypes(SymbolVendor &Vendor);
+static void findVariables(SymbolVendor &Vendor);
+
+static void dumpSymbols(Debugger &Dbg);
 }
 } // namespace opts
 
 static llvm::ManagedStatic<SystemLifetimeManager> DebuggerLifetime;
 
 void opts::breakpoint::dumpState(const BreakpointList &List, LinePrinter &P) {
   P.formatLine("{0} breakpoint{1}", List.GetSize(), plural(List.GetSize()));
   if (List.GetSize() > 0)
if (!Dbg.GetCommandInterpreter().HandleCommand(
       P.formatLine("Failed: {0}", Result.GetErrorData());
       continue;
     }
 
     dumpState(Target->GetBreakpointList(/*internal*/ false), P);
   }
 }
 
-static void dumpSymbols(Debugger &Dbg) {
-  for (const auto &File : opts::symbols::InputFilenames) {
+Expected<CompilerDeclContext>
+opts::symbols::getDeclContext(SymbolVendor &Vendor) {
+  if (Context.empty())
+    return CompilerDeclContext();
+  VariableList List;
+  Vendor.FindGlobalVariables(ConstString(Context), nullptr, false, UINT32_MAX,
+                             List);
+  if (List.Empty()) {
+    return make_error<StringError>("Context search didn't find a match.",
+                                   inconvertibleErrorCode());
+  }
+  if (List.GetSize() > 1) {
+    return make_error<StringError>("Context search found multiple matches.",
+                                   inconvertibleErrorCode());
+  }
+  return List.GetVariableAtIndex(0)->GetDeclContext();
+}
+
+void opts::symbols::findFunctions(SymbolVendor &Vendor) {
+  SymbolContextList List;
+  if (Regex) {
+    RegularExpression RE(Name);
+    if (!RE.IsValid()) {
+      WithColor::error() << "`" << Name
+                         << "` is not a valid regular expression.\n";
+      return;
+    }
+    Vendor.FindFunctions(RE, true, false, List);
+  } else {
+    Expected<CompilerDeclContext> ContextOr = getDeclContext(Vendor);
+    if (!ContextOr) {
+      WithColor::error() << toString(ContextOr.takeError()) << "\n";
+      return;
+    }
+    CompilerDeclContext *ContextPtr =
+        ContextOr->IsValid() ? &*ContextOr : nullptr;
+
+    Vendor.FindFunctions(ConstString(Name), ContextPtr, getFunctionNameFlags(),
+                          true, false, List);
+  }
+  outs() << formatv("Found {0} functions:\n", List.GetSize());
+  StreamString Stream;
+  List.Dump(&Stream, nullptr);
+  outs() << Stream.GetData() << "\n";
+}
+
+void opts::symbols::findNamespaces(SymbolVendor &Vendor) {
+  Expected<CompilerDeclContext> ContextOr = getDeclContext(Vendor);
+  if (!ContextOr) {
+    WithColor::error() << toString(ContextOr.takeError()) << "\n";
+    return;
+  }
+  CompilerDeclContext *ContextPtr =
+      ContextOr->IsValid() ? &*ContextOr : nullptr;
+
+  SymbolContext SC;
+  CompilerDeclContext Result =
+      Vendor.FindNamespace(SC, ConstString(Name), ContextPtr);
+  if (Result)
+    outs() << "Found namespace: "
+           << Result.GetScopeQualifiedName().GetStringRef() << "\n";
+  else
+    outs() << "Namespace not found.\n";
+}
+
+void opts::symbols::findTypes(SymbolVendor &Vendor) {
+  Expected<CompilerDeclContext> ContextOr = getDeclContext(Vendor);
+  if (!ContextOr) {
+    WithColor::error() << toString(ContextOr.takeError()) << "\n";
+    return;
+  }
+  CompilerDeclContext *ContextPtr =
+      ContextOr->IsValid() ? &*ContextOr : nullptr;
+
+  SymbolContext SC;
+  DenseSet<SymbolFile *> SearchedFiles;
+  TypeMap Map;
+  Vendor.FindTypes(SC, ConstString(Name), ContextPtr, true, UINT32_MAX,
+                    SearchedFiles, Map);
+
+  outs() << formatv("Found {0} types:\n", Map.GetSize());
+  StreamString Stream;
+  Map.Dump(&Stream, false);
+  outs() << Stream.GetData() << "\n";
+}
+
+void opts::symbols::findVariables(SymbolVendor &Vendor) {
+  VariableList List;
+  if (Regex) {
+    RegularExpression RE(Name);
+    if (!RE.IsValid()) {
+      WithColor::error() << "`" << Name
+                         << "` is not a valid regular expression.\n";
+      return;
+    }
+    Vendor.FindGlobalVariables(RE, false, UINT32_MAX, List);
+  } else {
+    Expected<CompilerDeclContext> ContextOr = getDeclContext(Vendor);
+    if (!ContextOr) {
+      WithColor::error() << toString(ContextOr.takeError()) << "\n";
+      return;
+    }
+    CompilerDeclContext *ContextPtr =
+        ContextOr->IsValid() ? &*ContextOr : nullptr;
+
+    Vendor.FindGlobalVariables(ConstString(Name), ContextPtr, false, UINT32_MAX,
+                               List);
+  }
+  outs() << formatv("Found {0} variables:\n", List.GetSize());
+  StreamString Stream;
+  List.Dump(&Stream, false);
+  outs() << Stream.GetData() << "\n";
+}
+
+void opts::symbols::dumpSymbols(Debugger &Dbg) {
+  if (Find != FindType::None && Regex && !Context.empty()) {
+    WithColor::error()
+        << "Cannot search using both regular expressions and context.\n";
+    return;
+  }
+  if ((Find == FindType::Type || Find == FindType::Namespace) && Regex) {
+    WithColor::error() << "Cannot search for types and namespaces using "
+                          "regular expressions.\n";
+    return;
+  }
+  if (Find == FindType::Function && Regex && getFunctionNameFlags() != 0) {
+    WithColor::error() << "Cannot search for types using both regular "
+                          "expressions and function-flags.\n";
+    return;
+  }
+  for (const auto &File : InputFilenames) {
+    outs() << "Module: " << File << "\n";
     ModuleSpec Spec{FileSpec(File, false)};
     Spec.GetSymbolFileSpec().SetFile(File, false);
 
     auto ModulePtr = std::make_shared<lldb_private::Module>(Spec);
+    SymbolVendor *Vendor = ModulePtr->GetSymbolVendor();
+    if (!Vendor) {
+      WithColor::error() << "Module has no symbol vendor.\n";
+      continue;
+    }
 
+    switch(Find) {
+    case FindType::Function:
+      findFunctions(*Vendor);
+      break;
+    case FindType::Namespace:
+      findNamespaces(*Vendor);
+      break;
+    case FindType::Type:
+      findTypes(*Vendor);
+      break;
+    case FindType::Variable:
+      findVariables(*Vendor);
+      break;
+    case FindType::None:
       StreamString Stream;
       ModulePtr->ParseAllDebugSymbols();
       ModulePtr->Dump(&Stream);
-    llvm::outs() << Stream.GetData() << "\n";
-    llvm::outs().flush();
+      outs() << Stream.GetData() << "\n";
+      break;
+    }
+    outs().flush();
   }
 }
 
 static void dumpModules(Debugger &Dbg) {
   LinePrinter Printer(4, llvm::outs());
 
   for (const auto &File : opts::module::InputFilenames) {
     ModuleSpec Spec{FileSpec(File, false)};
int main(int argc, const char *argv[]) {
 
   auto Dbg = lldb_private::Debugger::CreateInstance();
 
   if (opts::BreakpointSubcommand)
     opts::breakpoint::evaluateBreakpoints(*Dbg);
   if (opts::ModuleSubcommand)
     dumpModules(*Dbg);
   else if (opts::SymbolsSubcommand)
-    dumpSymbols(*Dbg);
+    opts::symbols::dumpSymbols(*Dbg);
 
   DebuggerLifetime->Terminate();
   return 0;
 }