Automerge: Revert "[lldb][HostInfoMacOSX] Try to use DW_AT_LLVM_sysroot instead of xcrun when looking up SDK" (#129621)

Reverts llvm/llvm-project#128712

```
******************** TEST 'lldb-unit :: SymbolFile/DWARF/./SymbolFileDWARFTests/10/14' FAILED ********************
Script(shard):
--
GTEST_OUTPUT=json:/Users/ec2-user/jenkins/workspace/llvm.org/as-lldb-cmake/lldb-build/tools/lldb/unittests/SymbolFile/DWARF/./SymbolFileDWARFTests-lldb-unit-1021-10-14.json GTEST_SHUFFLE=1 GTEST_TOTAL_SHARDS=14 GTEST_SHARD_INDEX=10 GTEST_RANDOM_SEED=62233 /Users/ec2-user/jenkins/workspace/llvm.org/as-lldb-cmake/lldb-build/tools/lldb/unittests/SymbolFile/DWARF/./SymbolFileDWARFTests
--

Script:
--
/Users/ec2-user/jenkins/workspace/llvm.org/as-lldb-cmake/lldb-build/tools/lldb/unittests/SymbolFile/DWARF/./SymbolFileDWARFTests --gtest_filter=SDKPathParsingTests/SDKPathParsingMultiparamTests.TestSDKPathFromDebugInfo/6
--
/Users/ec2-user/jenkins/workspace/llvm.org/as-lldb-cmake/llvm-project/lldb/unittests/SymbolFile/DWARF/XcodeSDKModuleTests.cpp:265: Failure
Expected equality of these values:
  found_mismatch
    Which is: true
  expect_mismatch
    Which is: false

/Users/ec2-user/jenkins/workspace/llvm.org/as-lldb-cmake/llvm-project/lldb/unittests/SymbolFile/DWARF/XcodeSDKModuleTests.cpp:265
Expected equality of these values:
  found_mismatch
    Which is: true
  expect_mismatch
    Which is: false
```

Author: augusto2112

lldb/include/lldb/Host/macosx/HostInfoMacOSX.h

@@ -32,9 +32,6 @@ class HostInfoMacOSX : public HostInfoPosix {
   static FileSpec GetXcodeDeveloperDirectory();
 
   /// Query xcrun to find an Xcode SDK directory.
-  ///
-  /// Note, this is an expensive operation if the SDK we're querying
-  /// does not exist in an Xcode installation path on the host.
   static llvm::Expected<llvm::StringRef> GetSDKRoot(SDKOptions options);
   static llvm::Expected<llvm::StringRef> FindSDKTool(XcodeSDK sdk,
                                                      llvm::StringRef tool);

lldb/include/lldb/Utility/XcodeSDK.h

@@ -9,7 +9,6 @@
 #ifndef LLDB_UTILITY_SDK_H
 #define LLDB_UTILITY_SDK_H
 
-#include "lldb/Utility/FileSpec.h"
 #include "lldb/lldb-forward.h"
 #include "llvm/ADT/StringRef.h"
 #include "llvm/Support/VersionTuple.h"
@@ -24,7 +23,6 @@ namespace lldb_private {
 /// An abstraction for Xcode-style SDKs that works like \ref ArchSpec.
 class XcodeSDK {
   std::string m_name;
-  FileSpec m_sysroot;
 
 public:
   /// Different types of Xcode SDKs.
@@ -64,8 +62,6 @@ class XcodeSDK {
   /// directory component of a path one would pass to clang's -isysroot
   /// parameter. For example, "MacOSX.10.14.sdk".
   XcodeSDK(std::string &&name) : m_name(std::move(name)) {}
-  XcodeSDK(std::string name, FileSpec sysroot)
-      : m_name(std::move(name)), m_sysroot(std::move(sysroot)) {}
   static XcodeSDK GetAnyMacOS() { return XcodeSDK("MacOSX.sdk"); }
 
   /// The merge function follows a strict order to maintain monotonicity:
@@ -83,7 +79,6 @@ class XcodeSDK {
   llvm::VersionTuple GetVersion() const;
   Type GetType() const;
   llvm::StringRef GetString() const;
-  const FileSpec &GetSysroot() const;
   /// Whether this Xcode SDK supports Swift.
   bool SupportsSwift() const;
 

lldb/source/Plugins/Platform/MacOSX/PlatformDarwin.cpp

@@ -1425,9 +1425,6 @@ PlatformDarwin::ResolveSDKPathFromDebugInfo(Module &module) {
 
   auto [sdk, _] = std::move(*sdk_or_err);
 
-  if (FileSystem::Instance().Exists(sdk.GetSysroot()))
-    return sdk.GetSysroot().GetPath();
-
   auto path_or_err = HostInfo::GetSDKRoot(HostInfo::SDKOptions{sdk});
   if (!path_or_err)
     return llvm::createStringError(

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

@@ -993,26 +993,21 @@ XcodeSDK SymbolFileDWARF::ParseXcodeSDK(CompileUnit &comp_unit) {
   const char *sdk = cu_die.GetAttributeValueAsString(DW_AT_APPLE_sdk, nullptr);
   if (!sdk)
     return {};
-  std::string sysroot =
+  const char *sysroot =
       cu_die.GetAttributeValueAsString(DW_AT_LLVM_sysroot, "");
+  // Register the sysroot path remapping with the module belonging to
+  // the CU as well as the one belonging to the symbol file. The two
+  // would be different if this is an OSO object and module is the
+  // corresponding debug map, in which case both should be updated.
+  ModuleSP module_sp = comp_unit.GetModule();
+  if (module_sp)
+    module_sp->RegisterXcodeSDK(sdk, sysroot);
 
-  // RegisterXcodeSDK calls into xcrun which is not aware of CLT, which is
-  // expensive.
-  if (sysroot.find("/Library/Developer/CommandLineTools/SDKs") != 0) {
-    // Register the sysroot path remapping with the module belonging to
-    // the CU as well as the one belonging to the symbol file. The two
-    // would be different if this is an OSO object and module is the
-    // corresponding debug map, in which case both should be updated.
-    ModuleSP module_sp = comp_unit.GetModule();
-    if (module_sp)
-      module_sp->RegisterXcodeSDK(sdk, sysroot);
-
-    ModuleSP local_module_sp = m_objfile_sp->GetModule();
-    if (local_module_sp && local_module_sp != module_sp)
-      local_module_sp->RegisterXcodeSDK(sdk, sysroot);
-  }
+  ModuleSP local_module_sp = m_objfile_sp->GetModule();
+  if (local_module_sp && local_module_sp != module_sp)
+    local_module_sp->RegisterXcodeSDK(sdk, sysroot);
 
-  return {sdk, FileSpec{std::move(sysroot)}};
+  return {sdk};
 }
 
 size_t SymbolFileDWARF::ParseFunctions(CompileUnit &comp_unit) {

lldb/source/Utility/XcodeSDK.cpp

@@ -142,8 +142,6 @@ XcodeSDK::Type XcodeSDK::GetType() const {
 
 llvm::StringRef XcodeSDK::GetString() const { return m_name; }
 
-const FileSpec &XcodeSDK::GetSysroot() const { return m_sysroot; }
-
 bool XcodeSDK::Info::operator<(const Info &other) const {
   return std::tie(type, version, internal) <
          std::tie(other.type, other.version, other.internal);
@@ -155,24 +153,17 @@ bool XcodeSDK::Info::operator==(const Info &other) const {
 }
 
 void XcodeSDK::Merge(const XcodeSDK &other) {
-  auto add_internal_sdk_suffix = [](llvm::StringRef sdk) {
-    return (sdk.substr(0, sdk.size() - 3) + "Internal.sdk").str();
-  };
-
   // The "bigger" SDK always wins.
   auto l = Parse();
   auto r = other.Parse();
   if (l < r)
     *this = other;
   else {
     // The Internal flag always wins.
-    if (!l.internal && r.internal) {
-      if (llvm::StringRef(m_name).ends_with(".sdk"))
-        m_name = add_internal_sdk_suffix(m_name);
-
-      if (m_sysroot.GetFileNameExtension() == ".sdk")
-        m_sysroot.SetFilename(add_internal_sdk_suffix(m_sysroot.GetFilename()));
-    }
+    if (llvm::StringRef(m_name).ends_with(".sdk"))
+      if (!l.internal && r.internal)
+        m_name =
+            m_name.substr(0, m_name.size() - 3) + std::string("Internal.sdk");
   }
 }
 

lldb/unittests/SymbolFile/DWARF/XcodeSDKModuleTests.cpp

@@ -307,28 +307,13 @@ SDKPathParsingTestData sdkPathParsingTestCases[] = {
      .expect_internal_sdk = true,
      .expect_sdk_path_pattern = "Internal.sdk"},
 
-    /// Two CUs with a public (non-CommandLineTools) SDK each
-    {.input_sdk_paths = {"/Path/To/SDKs/iPhoneOS14.1.sdk",
-                         "/Path/To/SDKs/MacOSX11.3.sdk"},
-     .expect_mismatch = false,
-     .expect_internal_sdk = false,
-     .expect_sdk_path_pattern = "iPhoneOS14.1.sdk"},
-
-    /// One CU with CommandLineTools and the other a public SDK
+    /// Two CUs with an internal SDK each
     {.input_sdk_paths =
          {"/Library/Developer/CommandLineTools/SDKs/iPhoneOS14.1.sdk",
-          "/Path/To/SDKs/MacOSX11.3.sdk"},
+          "/Library/Developer/CommandLineTools/SDKs/MacOSX11.3.sdk"},
      .expect_mismatch = false,
      .expect_internal_sdk = false,
      .expect_sdk_path_pattern = "iPhoneOS14.1.sdk"},
-
-    /// One CU with CommandLineTools and the other an internal SDK
-    {.input_sdk_paths =
-         {"/Library/Developer/CommandLineTools/SDKs/iPhoneOS14.1.sdk",
-          "/Path/To/SDKs/MacOSX11.3.Internal.sdk"},
-     .expect_mismatch = false,
-     .expect_internal_sdk = true,
-     .expect_sdk_path_pattern = "iPhoneOS14.1.Internal.sdk"},
 };
 
 INSTANTIATE_TEST_SUITE_P(SDKPathParsingTests, SDKPathParsingMultiparamTests,

lldb/unittests/Utility/XcodeSDKTest.cpp

@@ -34,17 +34,12 @@ TEST(XcodeSDKTest, ParseTest) {
   EXPECT_EQ(XcodeSDK("MacOSX10.9.sdk").GetVersion(), llvm::VersionTuple(10, 9));
   EXPECT_EQ(XcodeSDK("MacOSX10.15.4.sdk").GetVersion(), llvm::VersionTuple(10, 15));
   EXPECT_EQ(XcodeSDK("MacOSX.sdk").IsAppleInternalSDK(), false);
-  EXPECT_EQ(
-      XcodeSDK("MacOSX.sdk", FileSpec{"/Path/To/MacOSX.sdk"}).GetSysroot(),
-      FileSpec("/Path/To/MacOSX.sdk"));
   EXPECT_EQ(XcodeSDK("MacOSX10.15.Internal.sdk").GetType(), XcodeSDK::MacOSX);
   EXPECT_EQ(XcodeSDK("MacOSX10.15.Internal.sdk").GetVersion(),
             llvm::VersionTuple(10, 15));
   EXPECT_EQ(XcodeSDK("MacOSX10.15.Internal.sdk").IsAppleInternalSDK(), true);
-  EXPECT_FALSE(XcodeSDK("MacOSX10.15.Internal.sdk").GetSysroot());
   EXPECT_EQ(XcodeSDK().GetType(), XcodeSDK::unknown);
   EXPECT_EQ(XcodeSDK().GetVersion(), llvm::VersionTuple());
-  EXPECT_FALSE(XcodeSDK().GetSysroot());
 }
 
 TEST(XcodeSDKTest, MergeTest) {
@@ -65,14 +60,6 @@ TEST(XcodeSDKTest, MergeTest) {
   XcodeSDK empty;
   empty.Merge(XcodeSDK("MacOSX10.14.Internal.sdk"));
   EXPECT_EQ(empty.GetString(), llvm::StringRef("MacOSX10.14.Internal.sdk"));
-  EXPECT_FALSE(empty.GetSysroot());
-  empty.Merge(XcodeSDK("MacOSX9.5.Internal.sdk", FileSpec{"/Path/To/9.5.sdk"}));
-  EXPECT_FALSE(empty.GetSysroot());
-  empty.Merge(XcodeSDK("MacOSX12.5.sdk", FileSpec{"/Path/To/12.5.sdk"}));
-  EXPECT_EQ(empty.GetSysroot(), FileSpec{"/Path/To/12.5.sdk"});
-  empty.Merge(XcodeSDK("MacOSX11.5.Internal.sdk",
-                       FileSpec{"/Path/To/12.5.Internal.sdk"}));
-  EXPECT_EQ(empty.GetSysroot(), FileSpec{"/Path/To/12.5.Internal.sdk"});
 }
 
 #ifndef _WIN32