[lldb] Don't create instance of SymbolFileDWARFDebugMap for non-Mach-O files

lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDebugMap.cpp

@@ -246,6 +246,10 @@ llvm::StringRef SymbolFileDWARFDebugMap::GetPluginDescriptionStatic() {
 }
 
 SymbolFile *SymbolFileDWARFDebugMap::CreateInstance(ObjectFileSP objfile_sp) {
+  assert(objfile_sp);
+  // Don't create a debug map if the object file isn't a Mach-O.
+  if (!objfile_sp->GetArchitecture().GetTriple().isAppleMachO())
+    return nullptr;
   return new SymbolFileDWARFDebugMap(std::move(objfile_sp));
 }
 

lldb/unittests/SymbolFile/DWARF/CMakeLists.txt

@@ -4,6 +4,7 @@ add_lldb_unittest(SymbolFileDWARFTests
   DWARFDIETest.cpp
   DWARFIndexCachingTest.cpp
   DWARFUnitTest.cpp
+  SymbolFileDWARFDebugMapTests.cpp
   SymbolFileDWARFTests.cpp
   XcodeSDKModuleTests.cpp
 

lldb/unittests/SymbolFile/DWARF/SymbolFileDWARFDebugMapTests.cpp

@@ -0,0 +1,154 @@
+//===-- SymbolFileDWARFDebugMapTests.cpp ----------------------------------===//
+//
+// 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 "Plugins/ObjectFile/ELF/ObjectFileELF.h"
+#include "Plugins/ObjectFile/Mach-O/ObjectFileMachO.h"
+#include "Plugins/SymbolFile/DWARF/SymbolFileDWARFDebugMap.h"
+#include "TestingSupport/SubsystemRAII.h"
+#include "TestingSupport/TestUtilities.h"
+
+#include "lldb/Core/Module.h"
+#include "llvm/Testing/Support/Error.h"
+
+#include "gtest/gtest.h"
+
+using namespace lldb;
+using namespace lldb_private;
+using namespace lldb_private::plugin::dwarf;
+
+class SymbolFileDWARFDebugMapTests : public testing::Test {
+  SubsystemRAII<ObjectFileELF, ObjectFileMachO> subsystems;
+};
+
+TEST_F(SymbolFileDWARFDebugMapTests, CreateInstanceReturnNonNullForMachOFile) {
+  // A Mach-O file built for arm64 CPU type and macOS platform.
+  const char *yamldata = R"(
+--- !mach-o
+FileHeader:
+  magic:           0xFEEDFACF
+  cputype:         0x0100000C
+  cpusubtype:      0x00000000
+  filetype:        0x00000001
+  ncmds:           1
+  sizeofcmds:      176
+  flags:           0x00002000
+  reserved:        0x00000000
+LoadCommands:
+  - cmd:             LC_BUILD_VERSION
+    cmdsize:         24
+    platform:        1
+    minos:           658944
+    sdk:             658944
+    ntools:          0
+  - cmd:             LC_SEGMENT_64
+    cmdsize:         152
+    segname:         __TEXT
+    vmaddr:          0
+    vmsize:          4
+    fileoff:         208
+    filesize:        4
+    maxprot:         7
+    initprot:        7
+    nsects:          1
+    flags:           0
+    Sections:
+      - sectname:        __text
+        segname:         __TEXT
+        addr:            0x0000000000000000
+        content:         'AABBCCDD'
+        size:            4
+        offset:          208
+        align:           0
+        reloff:          0x00000000
+        nreloc:          0
+        flags:           0x80000400
+        reserved1:       0x00000000
+        reserved2:       0x00000000
+        reserved3:       0x00000000
+...
+)";
+
+  // Perform setup.
+  llvm::Expected<TestFile> file = TestFile::fromYaml(yamldata);
+  EXPECT_THAT_EXPECTED(file, llvm::Succeeded());
+  auto module_sp = std::make_shared<Module>(file->moduleSpec());
+  ASSERT_NE(module_sp, nullptr);
+  auto object_file = module_sp->GetObjectFile();
+  ASSERT_NE(object_file, nullptr);
+
+  // The debug map should be non-null for Mach-O file.
+  auto debug_map =
+      SymbolFileDWARFDebugMap::CreateInstance(object_file->shared_from_this());
+  ASSERT_NE(debug_map, nullptr);
+}
+
+TEST_F(SymbolFileDWARFDebugMapTests, CreateInstanceReturnNullForNonMachOFile) {
+  // An ELF file.
+  const char *yamldata = R"(
+--- !ELF
+FileHeader:
+  Class:   ELFCLASS64
+  Data:    ELFDATA2LSB
+  Type:    ET_EXEC
+  Machine: EM_386
+DWARF:
+  debug_abbrev:
+    - Table:
+        - Code:            0x00000001
+          Tag:             DW_TAG_compile_unit
+          Children:        DW_CHILDREN_no
+          Attributes:
+            - Attribute:       DW_AT_addr_base
+              Form:            DW_FORM_sec_offset
+  debug_info:
+    - Version:         5
+      AddrSize:        4
+      UnitType:        DW_UT_compile
+      Entries:
+        - AbbrCode:        0x00000001
+          Values:
+            - Value:           0x8 # Offset of the first Address past the header
+        - AbbrCode:        0x0
+  debug_addr:
+    - Version: 5
+      AddressSize: 4
+      Entries:
+        - Address: 0x1234
+        - Address: 0x5678
+  debug_line:
+    - Length:          42
+      Version:         2
+      PrologueLength:  36
+      MinInstLength:   1
+      DefaultIsStmt:   1
+      LineBase:        251
+      LineRange:       14
+      OpcodeBase:      13
+      StandardOpcodeLengths: [ 0, 1, 1, 1, 1, 0, 0, 0, 1, 0, 0, 1 ]
+      IncludeDirs:
+        - '/tmp'
+      Files:
+        - Name:            main.cpp
+          DirIdx:          1
+          ModTime:         0
+          Length:          0
+)";
+
+  // Perform setup.
+  llvm::Expected<TestFile> file = TestFile::fromYaml(yamldata);
+  EXPECT_THAT_EXPECTED(file, llvm::Succeeded());
+  auto module_sp = std::make_shared<Module>(file->moduleSpec());
+  ASSERT_NE(module_sp, nullptr);
+  auto object_file = module_sp->GetObjectFile();
+  ASSERT_NE(object_file, nullptr);
+
+  // The debug map should be null for non-Mach-O (ELF) file.
+  auto debug_map =
+      SymbolFileDWARFDebugMap::CreateInstance(object_file->shared_from_this());
+  ASSERT_EQ(debug_map, nullptr);
+}