Add an explicit API to read the Xcode SDK DWARF attribute from compile units

When debugging from a SymbolMap the creation of CompileUnits for the
individual object files is so lazy that RegisterXcodeSDK() is not
invoked at all before the Swift TypeSystem wants to read it. This
patch fixes this by introducing an explicit
SymbolFile::ParseXcodeSDK() call that can be invoked deterministically
before the result is required.

<rdar://problem/62532151+62326862>

https://reviews.llvm.org/D79273

diff --git a/lldb/include/lldb/Core/Module.h b/lldb/include/lldb/Core/Module.h
index c8cb03e2dee8f6d600527659314538d7e23872e1..854ffda25b36ed611c38b6f64faf1d20c059f4c0 100644 (file)
--- a/lldb/include/lldb/Core/Module.h
+++ b/lldb/include/lldb/Core/Module.h
@@ -512,7 +512,6 @@ public:
 
   /// This callback will be called by SymbolFile implementations when
   /// parsing a compile unit that contains SDK information.
-  /// \param sdk will be merged with \p m_sdk.
   /// \param sysroot will be added to the path remapping dictionary.
   void RegisterXcodeSDK(llvm::StringRef sdk, llvm::StringRef sysroot);
 
@@ -864,11 +863,6 @@ public:
   bool RemapSourceFile(llvm::StringRef path, std::string &new_path) const;
   bool RemapSourceFile(const char *, std::string &) const = delete;
 
-  /// Return the Xcode SDK this module was compiled against.  This
-  /// is computed by merging the SDKs from each compilation unit in
-  /// the module.
-  XcodeSDK GetXcodeSDK() const { return m_xcode_sdk; }
-
   /// Update the ArchSpec to a more specific variant.
   bool MergeArchitecture(const ArchSpec &arch_spec);
 
@@ -984,9 +978,6 @@ protected:
   PathMappingList m_source_mappings =
       ModuleList::GetGlobalModuleListProperties().GetSymlinkMappings();
 
-  /// The (Xcode) SDK this module was compiled with.
-  XcodeSDK m_xcode_sdk;
-  
   lldb::SectionListUP m_sections_up; ///< Unified section list for module that
                                      /// is used by the ObjectFile and and
                                      /// ObjectFile instances for the debug info

diff --git a/lldb/include/lldb/Symbol/SymbolFile.h b/lldb/include/lldb/Symbol/SymbolFile.h
index 86c8af665d32a2335ecc87a5314cc06d198046b0..00a618e7d858457ff51119c313c8281d49cd87d3 100644 (file)
--- a/lldb/include/lldb/Symbol/SymbolFile.h
+++ b/lldb/include/lldb/Symbol/SymbolFile.h
@@ -18,6 +18,7 @@
 #include "lldb/Symbol/Type.h"
 #include "lldb/Symbol/TypeList.h"
 #include "lldb/Symbol/TypeSystem.h"
+#include "lldb/Utility/XcodeSDK.h"
 #include "lldb/lldb-private.h"
 #include "llvm/ADT/DenseSet.h"
 #include "llvm/Support/Errc.h"
@@ -128,6 +129,8 @@ public:
   Symtab *GetSymtab();
 
   virtual lldb::LanguageType ParseLanguage(CompileUnit &comp_unit) = 0;
+  /// Return the Xcode SDK comp_unit was compiled against.
+  virtual XcodeSDK ParseXcodeSDK(CompileUnit &comp_unit) { return {}; }
   virtual size_t ParseFunctions(CompileUnit &comp_unit) = 0;
   virtual bool ParseLineTable(CompileUnit &comp_unit) = 0;
   virtual bool ParseDebugMacros(CompileUnit &comp_unit) = 0;

diff --git a/lldb/source/Core/Module.cpp b/lldb/source/Core/Module.cpp
index 658bcff6739d066c3e07d14cad2ebbc81838aea8..e5fb86ee252b86218d46d064c3ce683c8351cd5e 100644 (file)
--- a/lldb/source/Core/Module.cpp
+++ b/lldb/source/Core/Module.cpp
@@ -1598,9 +1598,6 @@ bool Module::RemapSourceFile(llvm::StringRef path,
 
 void Module::RegisterXcodeSDK(llvm::StringRef sdk_name, llvm::StringRef sysroot) {
   XcodeSDK sdk(sdk_name.str());
-  if (m_xcode_sdk == sdk)
-    return;
-  m_xcode_sdk.Merge(sdk);
   PlatformSP module_platform =
       Platform::GetPlatformForArchitecture(GetArchitecture(), nullptr);
   ConstString sdk_path(module_platform->GetSDKPath(sdk));

diff --git a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp
index ca7710d8ab143964e11524245104b7ea542ec0ab..f9a4a68c5fecbf979affc56bc364b50eb14db46a 100644 (file)
--- a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp
+++ b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.cpp
@@ -664,12 +664,6 @@ lldb::CompUnitSP SymbolFileDWARF::ParseCompileUnit(DWARFCompileUnit &dwarf_cu) {
         const DWARFBaseDIE cu_die =
             dwarf_cu.GetNonSkeletonUnit().GetUnitDIEOnly();
         if (cu_die) {
-          if (const char *sdk =
-                  cu_die.GetAttributeValueAsString(DW_AT_APPLE_sdk, nullptr)) {
-            const char *sysroot =
-                cu_die.GetAttributeValueAsString(DW_AT_LLVM_sysroot, "");
-            module_sp->RegisterXcodeSDK(sdk, sysroot);
-          }
           FileSpec cu_file_spec(cu_die.GetName(), dwarf_cu.GetPathStyle());
           MakeAbsoluteAndRemap(cu_file_spec, dwarf_cu, module_sp);
 
@@ -778,6 +772,26 @@ lldb::LanguageType SymbolFileDWARF::ParseLanguage(CompileUnit &comp_unit) {
     return eLanguageTypeUnknown;
 }
 
+XcodeSDK SymbolFileDWARF::ParseXcodeSDK(CompileUnit &comp_unit) {
+  std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
+  DWARFUnit *dwarf_cu = GetDWARFCompileUnit(&comp_unit);
+  if (!dwarf_cu)
+    return {};
+  ModuleSP module_sp = m_objfile_sp->GetModule();
+  if (!module_sp)
+    return {};
+  const DWARFBaseDIE cu_die = dwarf_cu->GetNonSkeletonUnit().GetUnitDIEOnly();
+  if (!cu_die)
+    return {};
+  const char *sdk = cu_die.GetAttributeValueAsString(DW_AT_APPLE_sdk, nullptr);
+  if (!sdk)
+    return {};
+  const char *sysroot =
+      cu_die.GetAttributeValueAsString(DW_AT_LLVM_sysroot, "");
+  module_sp->RegisterXcodeSDK(sdk, sysroot);
+  return {sdk};
+}
+
 size_t SymbolFileDWARF::ParseFunctions(CompileUnit &comp_unit) {
   static Timer::Category func_cat(LLVM_PRETTY_FUNCTION);
   Timer scoped_timer(func_cat, "SymbolFileDWARF::ParseFunctions");

diff --git a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.h b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.h
index de81145e78c2915a888c316f33bf30d84b8a7c7b..1e4a793e8b1aaa3a56ea28a0326b863c4f62f93c 100644 (file)
--- a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.h
+++ b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARF.h
@@ -106,6 +106,9 @@ public:
   lldb::LanguageType
   ParseLanguage(lldb_private::CompileUnit &comp_unit) override;
 
+  lldb_private::XcodeSDK
+  ParseXcodeSDK(lldb_private::CompileUnit &comp_unit) override;
+
   size_t ParseFunctions(lldb_private::CompileUnit &comp_unit) override;
 
   bool ParseLineTable(lldb_private::CompileUnit &comp_unit) override;

diff --git a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDebugMap.cpp b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDebugMap.cpp
index a177a56d5e13152d543321323d95a8e32215a90a..e8b9b1643ee5f3a79fd1cc53c085e318b7a60eaa 100644 (file)
--- a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDebugMap.cpp
+++ b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDebugMap.cpp
@@ -628,6 +628,15 @@ SymbolFileDWARFDebugMap::ParseLanguage(CompileUnit &comp_unit) {
   return eLanguageTypeUnknown;
 }
 
+XcodeSDK
+SymbolFileDWARFDebugMap::ParseXcodeSDK(CompileUnit &comp_unit) {
+  std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
+  SymbolFileDWARF *oso_dwarf = GetSymbolFile(comp_unit);
+  if (oso_dwarf)
+    return oso_dwarf->ParseXcodeSDK(comp_unit);
+  return {};
+}
+
 size_t SymbolFileDWARFDebugMap::ParseFunctions(CompileUnit &comp_unit) {
   std::lock_guard<std::recursive_mutex> guard(GetModuleMutex());
   SymbolFileDWARF *oso_dwarf = GetSymbolFile(comp_unit);

diff --git a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDebugMap.h b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDebugMap.h
index fcbb0489b82d617a5212765ba1999de0408644ad..729a5303abefb3b01c030f14cb4e472f3732ae50 100644 (file)
--- a/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDebugMap.h
+++ b/lldb/source/Plugins/SymbolFile/DWARF/SymbolFileDWARFDebugMap.h
@@ -58,6 +58,9 @@ public:
   lldb::LanguageType
   ParseLanguage(lldb_private::CompileUnit &comp_unit) override;
 
+  lldb_private::XcodeSDK
+  ParseXcodeSDK(lldb_private::CompileUnit &comp_unit) override;
+
   size_t ParseFunctions(lldb_private::CompileUnit &comp_unit) override;
 
   bool ParseLineTable(lldb_private::CompileUnit &comp_unit) override;

diff --git a/lldb/unittests/SymbolFile/DWARF/XcodeSDKModuleTests.cpp b/lldb/unittests/SymbolFile/DWARF/XcodeSDKModuleTests.cpp
index efc9fe1763a51bedffa68e3f15e5916a5da04df7..bbcdb85bc903c030abfc921d3bd2639c67a14db0 100644 (file)
--- a/lldb/unittests/SymbolFile/DWARF/XcodeSDKModuleTests.cpp
+++ b/lldb/unittests/SymbolFile/DWARF/XcodeSDKModuleTests.cpp
@@ -64,13 +64,13 @@ debug_info:
 
   auto triple = "x86_64-apple-macosx";
   YAMLModuleTester t(yamldata, triple);
-  auto module = t.GetModule();
   auto dwarf_unit_sp = t.GetDwarfUnit();
   auto *dwarf_cu = llvm::cast<DWARFCompileUnit>(dwarf_unit_sp.get());
   ASSERT_TRUE((bool)dwarf_cu);
-  ASSERT_TRUE((bool)dwarf_cu->GetSymbolFileDWARF().GetCompUnitForDWARFCompUnit(
-      *dwarf_cu));
-  XcodeSDK sdk = module->GetXcodeSDK();
+  SymbolFileDWARF &sym_file = dwarf_cu->GetSymbolFileDWARF();
+  CompUnitSP comp_unit = sym_file.GetCompileUnitAtIndex(0);
+  ASSERT_TRUE((bool)comp_unit.get());
+  XcodeSDK sdk = sym_file.ParseXcodeSDK(*comp_unit);
   ASSERT_EQ(sdk.GetType(), XcodeSDK::Type::MacOSX);
 }
 #endif