From 675767a5910d2ec77ef8b51c78fe312cf9022896 Mon Sep 17 00:00:00 2001 From: Davide Italiano Date: Tue, 27 Mar 2018 19:40:50 +0000 Subject: [PATCH] Use the DWARF linkage name when importing C++ methods. When importing C++ methods into clang AST nodes from the DWARF symbol table, preserve the DW_AT_linkage_name and use it as the linker ("asm") name for the symbol. Concretely, this enables `expression` to call into names that use the GNU `abi_tag` extension, and enables lldb to call into code using std::string or std::list from recent versions of libstdc++. See https://bugs.llvm.org/show_bug.cgi?id=35310 . It also seems broadly more robust than relying on the DWARF->clang->codegen pipeline to roundtrip properly, but I'm not immediately aware of any other cases in which it makes a difference. Patch by Nelson Elhage! Differential Revision: https://reviews.llvm.org/D40283 llvm-svn: 328658 --- lldb/include/lldb/Symbol/ClangASTContext.h | 1 + .../test/expression_command/pr35310/Makefile | 5 +++ .../pr35310/TestExprsBug35310.py | 39 +++++++++++++++++++ .../test/expression_command/pr35310/main.cpp | 19 +++++++++ .../Clang/ClangExpressionDeclMap.cpp | 2 +- .../SymbolFile/DWARF/DWARFASTParserClang.cpp | 13 ++++--- lldb/source/Symbol/ClangASTContext.cpp | 7 +++- 7 files changed, 78 insertions(+), 8 deletions(-) create mode 100644 lldb/packages/Python/lldbsuite/test/expression_command/pr35310/Makefile create mode 100644 lldb/packages/Python/lldbsuite/test/expression_command/pr35310/TestExprsBug35310.py create mode 100644 lldb/packages/Python/lldbsuite/test/expression_command/pr35310/main.cpp diff --git a/lldb/include/lldb/Symbol/ClangASTContext.h b/lldb/include/lldb/Symbol/ClangASTContext.h index e02e05dd5718..f5478e861d03 100644 --- a/lldb/include/lldb/Symbol/ClangASTContext.h +++ b/lldb/include/lldb/Symbol/ClangASTContext.h @@ -824,6 +824,7 @@ public: clang::CXXMethodDecl * AddMethodToCXXRecordType(lldb::opaque_compiler_type_t type, const char *name, + const char *mangled_name, const CompilerType &method_type, lldb::AccessType access, bool is_virtual, bool is_static, bool is_inline, bool is_explicit, diff --git a/lldb/packages/Python/lldbsuite/test/expression_command/pr35310/Makefile b/lldb/packages/Python/lldbsuite/test/expression_command/pr35310/Makefile new file mode 100644 index 000000000000..8a7102e347af --- /dev/null +++ b/lldb/packages/Python/lldbsuite/test/expression_command/pr35310/Makefile @@ -0,0 +1,5 @@ +LEVEL = ../../make + +CXX_SOURCES := main.cpp + +include $(LEVEL)/Makefile.rules diff --git a/lldb/packages/Python/lldbsuite/test/expression_command/pr35310/TestExprsBug35310.py b/lldb/packages/Python/lldbsuite/test/expression_command/pr35310/TestExprsBug35310.py new file mode 100644 index 000000000000..6cc479401de5 --- /dev/null +++ b/lldb/packages/Python/lldbsuite/test/expression_command/pr35310/TestExprsBug35310.py @@ -0,0 +1,39 @@ +from __future__ import print_function + +import lldb +from lldbsuite.test.decorators import * +from lldbsuite.test.lldbtest import * +from lldbsuite.test import lldbutil + +class ExprBug35310(TestBase): + + mydir = TestBase.compute_mydir(__file__) + + def setUp(self): + # Call super's setUp(). + TestBase.setUp(self) + + self.main_source = "main.cpp" + self.main_source_spec = lldb.SBFileSpec(self.main_source) + + def test_issue35310(self): + """Test invoking functions with non-standard linkage names. + + The GNU abi_tag extension used by libstdc++ is a common source + of these, but they could originate from other reasons as well. + """ + self.build() + + (target, process, thread, bkpt) = lldbutil.run_to_source_breakpoint(self, + '// Break here', self.main_source_spec) + frame = thread.GetFrameAtIndex(0) + + value = frame.EvaluateExpression("a.test_abi_tag()") + self.assertTrue(value.IsValid()) + self.assertTrue(value.GetError().Success()) + self.assertEqual(value.GetValueAsSigned(0), 1) + + value = frame.EvaluateExpression("a.test_asm_name()") + self.assertTrue(value.IsValid()) + self.assertTrue(value.GetError().Success()) + self.assertEqual(value.GetValueAsSigned(0), 2) diff --git a/lldb/packages/Python/lldbsuite/test/expression_command/pr35310/main.cpp b/lldb/packages/Python/lldbsuite/test/expression_command/pr35310/main.cpp new file mode 100644 index 000000000000..a8e8a5c737a0 --- /dev/null +++ b/lldb/packages/Python/lldbsuite/test/expression_command/pr35310/main.cpp @@ -0,0 +1,19 @@ +#include + +class A { +public: + int __attribute__((abi_tag("cxx11"))) test_abi_tag() { + return 1; + } + int test_asm_name() asm("A_test_asm") { + return 2; + } +}; + +int main(int argc, char **argv) { + A a; + // Break here + a.test_abi_tag(); + a.test_asm_name(); + return 0; +} diff --git a/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionDeclMap.cpp b/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionDeclMap.cpp index 8a39e720eaba..76f08dc426aa 100644 --- a/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionDeclMap.cpp +++ b/lldb/source/Plugins/ExpressionParser/Clang/ClangExpressionDeclMap.cpp @@ -2166,7 +2166,7 @@ void ClangExpressionDeclMap::AddThisType(NameSearchContext &context, CXXMethodDecl *method_decl = ClangASTContext::GetASTContext(m_ast_context) ->AddMethodToCXXRecordType( - copied_clang_type.GetOpaqueQualType(), "$__lldb_expr", + copied_clang_type.GetOpaqueQualType(), "$__lldb_expr", NULL, method_type, lldb::eAccessPublic, is_virtual, is_static, is_inline, is_explicit, is_attr_used, is_artificial); diff --git a/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp b/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp index 73ca83dde74c..ff4f06514792 100644 --- a/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp +++ b/lldb/source/Plugins/SymbolFile/DWARF/DWARFASTParserClang.cpp @@ -276,6 +276,7 @@ TypeSP DWARFASTParserClang::ParseTypeFromDWARF(const SymbolContext &sc, bool is_forward_declaration = false; DWARFAttributes attributes; const char *type_name_cstr = NULL; + const char *mangled_name_cstr = NULL; ConstString type_name_const_str; Type::ResolveState resolve_state = Type::eResolveStateUnresolved; uint64_t byte_size = 0; @@ -1231,9 +1232,8 @@ TypeSP DWARFASTParserClang::ParseTypeFromDWARF(const SymbolContext &sc, case DW_AT_linkage_name: case DW_AT_MIPS_linkage_name: - break; // mangled = - // form_value.AsCString(&dwarf->get_debug_str_data()); - // break; + mangled_name_cstr = form_value.AsCString(); + break; case DW_AT_type: type_die_form = form_value; break; @@ -1594,9 +1594,10 @@ TypeSP DWARFASTParserClang::ParseTypeFromDWARF(const SymbolContext &sc, clang::CXXMethodDecl *cxx_method_decl = m_ast.AddMethodToCXXRecordType( class_opaque_type.GetOpaqueQualType(), - type_name_cstr, clang_type, accessibility, - is_virtual, is_static, is_inline, is_explicit, - is_attr_used, is_artificial); + type_name_cstr, mangled_name_cstr, clang_type, + accessibility, is_virtual, is_static, + is_inline, is_explicit, is_attr_used, + is_artificial); type_handled = cxx_method_decl != NULL; diff --git a/lldb/source/Symbol/ClangASTContext.cpp b/lldb/source/Symbol/ClangASTContext.cpp index df2d25c8d1ed..56aa3f71b2b6 100644 --- a/lldb/source/Symbol/ClangASTContext.cpp +++ b/lldb/source/Symbol/ClangASTContext.cpp @@ -7889,7 +7889,7 @@ clang::VarDecl *ClangASTContext::AddVariableToRecordType( } clang::CXXMethodDecl *ClangASTContext::AddMethodToCXXRecordType( - lldb::opaque_compiler_type_t type, const char *name, + lldb::opaque_compiler_type_t type, const char *name, const char *mangled_name, const CompilerType &method_clang_type, lldb::AccessType access, bool is_virtual, bool is_static, bool is_inline, bool is_explicit, bool is_attr_used, bool is_artificial) { @@ -8009,6 +8009,11 @@ clang::CXXMethodDecl *ClangASTContext::AddMethodToCXXRecordType( if (is_attr_used) cxx_method_decl->addAttr(clang::UsedAttr::CreateImplicit(*getASTContext())); + if (mangled_name != NULL) { + cxx_method_decl->addAttr( + clang::AsmLabelAttr::CreateImplicit(*getASTContext(), mangled_name)); + } + // Populate the method decl with parameter decls llvm::SmallVector params;