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| //===-- DWARFExpressionTest.cpp ----------------------------------*- 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 "lldb/Expression/DWARFExpression.h"
#include "../../source/Plugins/SymbolFile/DWARF/DWARFUnit.h"
#include "../../source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.h"
#include "lldb/Core/Module.h"
#include "lldb/Core/Section.h"
#include "lldb/Core/Value.h"
#include "lldb/Core/dwarf.h"
#include "lldb/Symbol/ObjectFile.h"
#include "lldb/Utility/StreamString.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ObjectYAML/DWARFEmitter.h"
#include "llvm/Testing/Support/Error.h"
#include "gtest/gtest.h"
using namespace lldb_private;
static llvm::Expected<Scalar> Evaluate(llvm::ArrayRef<uint8_t> expr,
lldb::ModuleSP module_sp = {},
DWARFUnit *unit = nullptr) {
DataExtractor extractor(expr.data(), expr.size(), lldb::eByteOrderLittle,
/*addr_size*/ 4);
Value result;
Status status;
if (!DWARFExpression::Evaluate(
/*exe_ctx*/ nullptr, /*reg_ctx*/ nullptr, module_sp, extractor, unit,
lldb::eRegisterKindLLDB,
/*initial_value_ptr*/ nullptr,
/*object_address_ptr*/ nullptr, result, &status))
return status.ToError();
return result.GetScalar();
}
/// A mock module holding an object file parsed from YAML.
class YAMLModule : public lldb_private::Module {
public:
YAMLModule(ArchSpec &arch) : Module(FileSpec("test"), arch) {}
void SetObjectFile(lldb::ObjectFileSP obj_file) { m_objfile_sp = obj_file; }
ObjectFile *GetObjectFile() override { return m_objfile_sp.get(); }
};
/// A mock object file that can be parsed from YAML.
class YAMLObjectFile : public lldb_private::ObjectFile {
const lldb::ModuleSP m_module_sp;
llvm::StringMap<std::unique_ptr<llvm::MemoryBuffer>> &m_section_map;
/// Because there is only one DataExtractor in the ObjectFile
/// interface, all sections are copied into a contiguous buffer.
std::vector<char> m_buffer;
public:
YAMLObjectFile(const lldb::ModuleSP &module_sp,
llvm::StringMap<std::unique_ptr<llvm::MemoryBuffer>> &map)
: ObjectFile(module_sp, &module_sp->GetFileSpec(), /*file_offset*/ 0,
/*length*/ 0, /*data_sp*/ nullptr, /*data_offset*/ 0),
m_module_sp(module_sp), m_section_map(map) {}
/// Callback for initializing the module's list of sections.
void CreateSections(SectionList &unified_section_list) override {
lldb::offset_t total_bytes = 0;
for (auto &entry : m_section_map)
total_bytes += entry.getValue()->getBufferSize();
m_buffer.reserve(total_bytes);
m_data =
DataExtractor(m_buffer.data(), total_bytes, lldb::eByteOrderLittle, 4);
lldb::user_id_t sect_id = 1;
for (auto &entry : m_section_map) {
llvm::StringRef name = entry.getKey();
lldb::SectionType sect_type =
llvm::StringSwitch<lldb::SectionType>(name)
.Case("debug_info", lldb::eSectionTypeDWARFDebugInfo)
.Case("debug_abbrev", lldb::eSectionTypeDWARFDebugAbbrev);
auto &membuf = entry.getValue();
lldb::addr_t file_vm_addr = 0;
lldb::addr_t vm_size = 0;
lldb::offset_t file_offset = m_buffer.size();
lldb::offset_t file_size = membuf->getBufferSize();
m_buffer.resize(file_offset + file_size);
memcpy(m_buffer.data() + file_offset, membuf->getBufferStart(),
file_size);
uint32_t log2align = 0;
uint32_t flags = 0;
auto section_sp = std::make_shared<lldb_private::Section>(
m_module_sp, this, sect_id++, ConstString(name), sect_type,
file_vm_addr, vm_size, file_offset, file_size, log2align, flags);
unified_section_list.AddSection(section_sp);
}
}
/// \{
/// Stub methods that aren't needed here.
ConstString GetPluginName() override { return ConstString("YAMLObjectFile"); }
uint32_t GetPluginVersion() override { return 0; }
void Dump(Stream *s) override {}
uint32_t GetAddressByteSize() const override { return 8; }
uint32_t GetDependentModules(FileSpecList &file_list) override { return 0; }
bool IsExecutable() const override { return 0; }
ArchSpec GetArchitecture() override { return {}; }
Symtab *GetSymtab() override { return nullptr; }
bool IsStripped() override { return false; }
UUID GetUUID() override { return {}; }
lldb::ByteOrder GetByteOrder() const override {
return lldb::eByteOrderLittle;
}
bool ParseHeader() override { return false; }
Type CalculateType() override { return {}; }
Strata CalculateStrata() override { return {}; }
/// \}
};
/// Helper class that can construct a module from YAML and evaluate
/// DWARF expressions on it.
class YAMLModuleTester {
llvm::StringMap<std::unique_ptr<llvm::MemoryBuffer>> m_sections_map;
lldb::ModuleSP m_module_sp;
lldb::ObjectFileSP m_objfile_sp;
DWARFUnitSP m_dwarf_unit;
std::unique_ptr<SymbolFileDWARF> m_symfile_dwarf;
public:
/// Parse the debug info sections from the YAML description.
YAMLModuleTester(llvm::StringRef yaml_data, llvm::StringRef triple) {
FileSystem::Initialize();
auto sections_map = llvm::DWARFYAML::EmitDebugSections(yaml_data, true);
if (!sections_map)
return;
m_sections_map = std::move(*sections_map);
ArchSpec arch(triple);
m_module_sp = std::make_shared<YAMLModule>(arch);
m_objfile_sp = std::make_shared<YAMLObjectFile>(m_module_sp, m_sections_map);
static_cast<YAMLModule *>(m_module_sp.get())->SetObjectFile(m_objfile_sp);
lldb::user_id_t uid = 0;
llvm::StringRef raw_debug_info = m_sections_map["debug_info"]->getBuffer();
lldb_private::DataExtractor debug_info(
raw_debug_info.data(), raw_debug_info.size(),
m_objfile_sp->GetByteOrder(), m_objfile_sp->GetAddressByteSize());
lldb::offset_t offset_ptr = 0;
m_symfile_dwarf = std::make_unique<SymbolFileDWARF>(m_objfile_sp, nullptr);
llvm::Expected<DWARFUnitSP> dwarf_unit = DWARFUnit::extract(
*m_symfile_dwarf, uid,
*static_cast<lldb_private::DWARFDataExtractor *>(&debug_info),
DIERef::DebugInfo, &offset_ptr);
if (dwarf_unit)
m_dwarf_unit = dwarf_unit.get();
}
~YAMLModuleTester() { FileSystem::Terminate(); }
DWARFUnitSP GetDwarfUnit() { return m_dwarf_unit; }
// Evaluate a raw DWARF expression.
llvm::Expected<Scalar> Eval(llvm::ArrayRef<uint8_t> expr) {
return ::Evaluate(expr, m_module_sp, m_dwarf_unit.get());
}
};
/// Unfortunately Scalar's operator==() is really picky.
static Scalar GetScalar(unsigned bits, uint64_t value, bool sign) {
Scalar scalar;
auto type = Scalar::GetBestTypeForBitSize(bits, sign);
switch (type) {
case Scalar::e_sint:
scalar = Scalar((int)value);
break;
case Scalar::e_slong:
scalar = Scalar((long)value);
break;
case Scalar::e_slonglong:
scalar = Scalar((long long)value);
break;
case Scalar::e_uint:
scalar = Scalar((unsigned int)value);
break;
case Scalar::e_ulong:
scalar = Scalar((unsigned long)value);
break;
case Scalar::e_ulonglong:
scalar = Scalar((unsigned long long)value);
break;
default:
llvm_unreachable("not implemented");
}
scalar.TruncOrExtendTo(type, bits);
if (sign)
scalar.MakeSigned();
else
scalar.MakeUnsigned();
return scalar;
}
TEST(DWARFExpression, DW_OP_pick) {
EXPECT_THAT_EXPECTED(Evaluate({DW_OP_lit1, DW_OP_lit0, DW_OP_pick, 0}),
llvm::HasValue(0));
EXPECT_THAT_EXPECTED(Evaluate({DW_OP_lit1, DW_OP_lit0, DW_OP_pick, 1}),
llvm::HasValue(1));
EXPECT_THAT_EXPECTED(Evaluate({DW_OP_lit1, DW_OP_lit0, DW_OP_pick, 2}),
llvm::Failed());
}
TEST(DWARFExpression, DW_OP_convert) {
/// Auxiliary debug info.
const char *yamldata =
"debug_abbrev:\n"
" - Code: 0x00000001\n"
" Tag: DW_TAG_compile_unit\n"
" Children: DW_CHILDREN_yes\n"
" Attributes:\n"
" - Attribute: DW_AT_language\n"
" Form: DW_FORM_data2\n"
" - Code: 0x00000002\n"
" Tag: DW_TAG_base_type\n"
" Children: DW_CHILDREN_no\n"
" Attributes:\n"
" - Attribute: DW_AT_encoding\n"
" Form: DW_FORM_data1\n"
" - Attribute: DW_AT_byte_size\n"
" Form: DW_FORM_data1\n"
"debug_info:\n"
" - Length:\n"
" TotalLength: 0\n"
" Version: 4\n"
" AbbrOffset: 0\n"
" AddrSize: 8\n"
" Entries:\n"
" - AbbrCode: 0x00000001\n"
" Values:\n"
" - Value: 0x000000000000000C\n"
// 0x0000000e:
" - AbbrCode: 0x00000002\n"
" Values:\n"
" - Value: 0x0000000000000007\n" // DW_ATE_unsigned
" - Value: 0x0000000000000004\n"
// 0x00000011:
" - AbbrCode: 0x00000002\n"
" Values:\n"
" - Value: 0x0000000000000007\n" // DW_ATE_unsigned
" - Value: 0x0000000000000008\n"
// 0x00000014:
" - AbbrCode: 0x00000002\n"
" Values:\n"
" - Value: 0x0000000000000005\n" // DW_ATE_signed
" - Value: 0x0000000000000008\n"
// 0x00000017:
" - AbbrCode: 0x00000002\n"
" Values:\n"
" - Value: 0x0000000000000008\n" // DW_ATE_unsigned_char
" - Value: 0x0000000000000001\n"
// 0x0000001a:
" - AbbrCode: 0x00000002\n"
" Values:\n"
" - Value: 0x0000000000000006\n" // DW_ATE_signed_char
" - Value: 0x0000000000000001\n"
// 0x0000001d:
" - AbbrCode: 0x00000002\n"
" Values:\n"
" - Value: 0x000000000000000b\n" // DW_ATE_numeric_string
" - Value: 0x0000000000000001\n"
""
" - AbbrCode: 0x00000000\n"
" Values: []\n";
uint8_t offs_uint32_t = 0x0000000e;
uint8_t offs_uint64_t = 0x00000011;
uint8_t offs_sint64_t = 0x00000014;
uint8_t offs_uchar = 0x00000017;
uint8_t offs_schar = 0x0000001a;
YAMLModuleTester t(yamldata, "i386-unknown-linux");
ASSERT_TRUE((bool)t.GetDwarfUnit());
// Constant is given as little-endian.
bool is_signed = true;
bool not_signed = false;
//
// Positive tests.
//
// Truncate to default unspecified (pointer-sized) type.
EXPECT_THAT_EXPECTED(
t.Eval({DW_OP_const8u, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77, 0x88, //
DW_OP_convert, 0x00}),
llvm::HasValue(GetScalar(32, 0x44332211, not_signed)));
// Truncate to 32 bits.
EXPECT_THAT_EXPECTED(t.Eval({DW_OP_const8u, //
0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77, 0x88,//
DW_OP_convert, offs_uint32_t}),
llvm::HasValue(GetScalar(32, 0x44332211, not_signed)));
// Leave as is.
EXPECT_THAT_EXPECTED(
t.Eval({DW_OP_const8u, 0x11, 0x22, 0x33, 0x44, 0x55, 0x66, 0x77, 0x88, //
DW_OP_convert, offs_uint64_t}),
llvm::HasValue(GetScalar(64, 0x8877665544332211, not_signed)));
// Sign-extend to 64 bits.
EXPECT_THAT_EXPECTED(
t.Eval({DW_OP_const4s, 0xcc, 0xdd, 0xee, 0xff, //
DW_OP_convert, offs_sint64_t}),
llvm::HasValue(GetScalar(64, 0xffffffffffeeddcc, is_signed)));
// Truncate to 8 bits.
EXPECT_THAT_EXPECTED(t.Eval({DW_OP_const4s, 'A', 'B', 'C', 'D', 0xee, 0xff, //
DW_OP_convert, offs_uchar}),
llvm::HasValue(GetScalar(8, 'A', not_signed)));
// Also truncate to 8 bits.
EXPECT_THAT_EXPECTED(t.Eval({DW_OP_const4s, 'A', 'B', 'C', 'D', 0xee, 0xff, //
DW_OP_convert, offs_schar}),
llvm::HasValue(GetScalar(8, 'A', is_signed)));
//
// Errors.
//
// No Module.
EXPECT_THAT_ERROR(Evaluate({DW_OP_const1s, 'X', DW_OP_convert, 0x00}, nullptr,
t.GetDwarfUnit().get())
.takeError(),
llvm::Failed());
// No DIE.
EXPECT_THAT_ERROR(
t.Eval({DW_OP_const1s, 'X', DW_OP_convert, 0x01}).takeError(),
llvm::Failed());
// Unsupported.
EXPECT_THAT_ERROR(
t.Eval({DW_OP_const1s, 'X', DW_OP_convert, 0x1d}).takeError(),
llvm::Failed());
}
|