Move the Xcode SDK path caching to HostInfo

When debugging a remote platform, the platform you get from
GetPlatformForArchitecture doesn't inherit from PlatformDarwin.
HostInfoMacOSX seems like the right place to have a global store of
local paths.

Differential Revision: https://reviews.llvm.org/D79364

Author: adrian-prantl

lldb/include/lldb/Host/HostInfoBase.h

@@ -93,7 +93,7 @@ class HostInfoBase {
                                            llvm::StringRef dir);
 
   /// Return the directory containing a specific Xcode SDK.
-  static std::string GetXcodeSDK(XcodeSDK sdk) { return {}; }
+  static llvm::StringRef GetXcodeSDKPath(XcodeSDK sdk) { return {}; }
 
 protected:
   static bool ComputeSharedLibraryDirectory(FileSpec &file_spec);

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

@@ -35,7 +35,7 @@ class HostInfoMacOSX : public HostInfoPosix {
   static std::string FindXcodeContentsDirectoryInPath(llvm::StringRef path);
 
   /// Query xcrun to find an Xcode SDK directory.
-  static std::string GetXcodeSDK(XcodeSDK sdk);
+  static llvm::StringRef GetXcodeSDKPath(XcodeSDK sdk);
 protected:
   static bool ComputeSupportExeDirectory(FileSpec &file_spec);
   static void ComputeHostArchitectureSupport(ArchSpec &arch_32,

lldb/include/lldb/Target/Platform.h

@@ -26,7 +26,6 @@
 #include "lldb/Utility/StructuredData.h"
 #include "lldb/Utility/Timeout.h"
 #include "lldb/Utility/UserIDResolver.h"
-#include "lldb/Utility/XcodeSDK.h"
 #include "lldb/lldb-private-forward.h"
 #include "lldb/lldb-public.h"
 #include "llvm/Support/VersionTuple.h"
@@ -435,8 +434,6 @@ class Platform : public PluginInterface {
     return lldb_private::ConstString();
   }
 
-  virtual llvm::StringRef GetSDKPath(lldb_private::XcodeSDK sdk) { return {}; }
-
   const std::string &GetRemoteURL() const { return m_remote_url; }
 
   bool IsHost() const {

lldb/source/Core/Module.cpp

@@ -18,6 +18,7 @@
 #include "lldb/Core/Section.h"
 #include "lldb/Host/FileSystem.h"
 #include "lldb/Host/Host.h"
+#include "lldb/Host/HostInfo.h"
 #include "lldb/Interpreter/CommandInterpreter.h"
 #include "lldb/Interpreter/ScriptInterpreter.h"
 #include "lldb/Symbol/CompileUnit.h"
@@ -33,7 +34,6 @@
 #include "lldb/Symbol/TypeMap.h"
 #include "lldb/Symbol/TypeSystem.h"
 #include "lldb/Target/Language.h"
-#include "lldb/Target/Platform.h"
 #include "lldb/Target/Process.h"
 #include "lldb/Target/Target.h"
 #include "lldb/Utility/DataBufferHeap.h"
@@ -1598,12 +1598,10 @@ bool Module::RemapSourceFile(llvm::StringRef path,
 
 void Module::RegisterXcodeSDK(llvm::StringRef sdk_name, llvm::StringRef sysroot) {
   XcodeSDK sdk(sdk_name.str());
-  PlatformSP module_platform =
-      Platform::GetPlatformForArchitecture(GetArchitecture(), nullptr);
-  ConstString sdk_path(module_platform->GetSDKPath(sdk));
+  ConstString sdk_path(HostInfo::GetXcodeSDKPath(sdk));
   if (!sdk_path)
     return;
-  // If merged SDK changed for a previously registered source path, update it.
+  // If the SDK changed for a previously registered source path, update it.
   // This could happend with -fdebug-prefix-map, otherwise it's unlikely.
   ConstString sysroot_cs(sysroot);
   if (!m_source_mappings.Replace(sysroot_cs, sdk_path, true))

lldb/source/Host/macosx/objcxx/HostInfoMacOSX.mm

@@ -297,7 +297,7 @@ static void ParseOSVersion(llvm::VersionTuple &version, NSString *Key) {
   }
 }
 
-std::string HostInfoMacOSX::GetXcodeSDK(XcodeSDK sdk) {
+static std::string GetXcodeSDK(XcodeSDK sdk) {
   XcodeSDK::Info info = sdk.Parse();
   std::string sdk_name = XcodeSDK::GetCanonicalName(info);
   auto find_sdk = [](std::string sdk_name) -> std::string {
@@ -361,3 +361,14 @@ static void ParseOSVersion(llvm::VersionTuple &version, NSString *Key) {
     return {};
   return path;
 }
+
+llvm::StringRef HostInfoMacOSX::GetXcodeSDKPath(XcodeSDK sdk) {
+  static llvm::StringMap<std::string> g_sdk_path;
+  static std::mutex g_sdk_path_mutex;
+
+  std::lock_guard<std::mutex> guard(g_sdk_path_mutex);
+  std::string &path = g_sdk_path[sdk.GetString()];
+  if (path.empty())
+    path = GetXcodeSDK(sdk);
+  return path;
+}

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

@@ -1761,14 +1761,6 @@ PlatformDarwin::FindXcodeContentsDirectoryInPath(llvm::StringRef path) {
   return {};
 }
 
-llvm::StringRef PlatformDarwin::GetSDKPath(XcodeSDK sdk) {
-  std::lock_guard<std::mutex> guard(m_sdk_path_mutex);
-  std::string &path = m_sdk_path[sdk.GetString()];
-  if (path.empty())
-    path = HostInfo::GetXcodeSDK(sdk);
-  return path;
-}
-
 FileSpec PlatformDarwin::GetXcodeContentsDirectory() {
   static FileSpec g_xcode_contents_path;
   static std::once_flag g_once_flag;
@@ -1797,7 +1789,7 @@ FileSpec PlatformDarwin::GetXcodeContentsDirectory() {
       }
     }
 
-    FileSpec fspec(HostInfo::GetXcodeSDK(XcodeSDK::GetAnyMacOS()));
+    FileSpec fspec(HostInfo::GetXcodeSDKPath(XcodeSDK::GetAnyMacOS()));
     if (fspec) {
       if (FileSystem::Instance().Exists(fspec)) {
         std::string xcode_contents_dir =

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

@@ -89,8 +89,6 @@ class PlatformDarwin : public PlatformPOSIX {
   llvm::Expected<lldb_private::StructuredData::DictionarySP>
   FetchExtendedCrashInformation(lldb_private::Process &process) override;
 
-  llvm::StringRef GetSDKPath(lldb_private::XcodeSDK sdk) override;
-
   static lldb_private::FileSpec GetXcodeContentsDirectory();
   static lldb_private::FileSpec GetXcodeDeveloperDirectory();
 

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

@@ -208,7 +208,8 @@ ConstString PlatformMacOSX::GetSDKDirectory(lldb_private::Target &target) {
   }
 
   // Use the default SDK as a fallback.
-  FileSpec fspec(HostInfo::GetXcodeSDK(lldb_private::XcodeSDK::GetAnyMacOS()));
+  FileSpec fspec(
+      HostInfo::GetXcodeSDKPath(lldb_private::XcodeSDK::GetAnyMacOS()));
   if (fspec) {
     if (FileSystem::Instance().Exists(fspec))
       return ConstString(fspec.GetPath());

lldb/unittests/Host/HostInfoTest.cpp

@@ -53,10 +53,10 @@ TEST_F(HostInfoTest, GetHostname) {
 
 #if defined(__APPLE__)
 TEST_F(HostInfoTest, GetXcodeSDK) {
-  EXPECT_FALSE(HostInfo::GetXcodeSDK(XcodeSDK("MacOSX.sdk")).empty());
+  EXPECT_FALSE(HostInfo::GetXcodeSDKPath(XcodeSDK("MacOSX.sdk")).empty());
   // These are expected to fall back to an available version.
-  EXPECT_FALSE(HostInfo::GetXcodeSDK(XcodeSDK("MacOSX9999.sdk")).empty());
+  EXPECT_FALSE(HostInfo::GetXcodeSDKPath(XcodeSDK("MacOSX9999.sdk")).empty());
   // This is expected to fail.
-  EXPECT_TRUE(HostInfo::GetXcodeSDK(XcodeSDK("CeciNestPasUnOS.sdk")).empty());
+  EXPECT_TRUE(HostInfo::GetXcodeSDKPath(XcodeSDK("CeciNestPasUnOS.sdk")).empty());
 }
 #endif