Update prebuilt Clang to r416183b from Android.

https://android.googlesource.com/platform/prebuilts/clang/host/
linux-x86/+/06a71ddac05c22edb2d10b590e1769b3f8619bef

clang 12.0.5 (based on r416183b) from build 7284624.

Change-Id: I277a316abcf47307562d8b748b84870f31a72866
Signed-off-by: Olivier Deprez <olivier.deprez@arm.com>
diff --git a/linux-x64/clang/include/llvm/ExecutionEngine/Orc/LLJIT.h b/linux-x64/clang/include/llvm/ExecutionEngine/Orc/LLJIT.h
index b54c7d8..ff0aa02 100644
--- a/linux-x64/clang/include/llvm/ExecutionEngine/Orc/LLJIT.h
+++ b/linux-x64/clang/include/llvm/ExecutionEngine/Orc/LLJIT.h
@@ -19,8 +19,8 @@
 #include "llvm/ExecutionEngine/Orc/IRCompileLayer.h"
 #include "llvm/ExecutionEngine/Orc/IRTransformLayer.h"
 #include "llvm/ExecutionEngine/Orc/JITTargetMachineBuilder.h"
-#include "llvm/ExecutionEngine/Orc/ObjectTransformLayer.h"
 #include "llvm/ExecutionEngine/Orc/ThreadSafeModule.h"
+#include "llvm/Support/Debug.h"
 #include "llvm/Support/ThreadPool.h"
 
 namespace llvm {
@@ -28,6 +28,8 @@
 
 class LLJITBuilderState;
 class LLLazyJITBuilderState;
+class ObjectTransformLayer;
+class TargetProcessControl;
 
 /// A pre-fabricated ORC JIT stack that can serve as an alternative to MCJIT.
 ///
@@ -35,8 +37,22 @@
 class LLJIT {
   template <typename, typename, typename> friend class LLJITBuilderSetters;
 
+  friend void setUpGenericLLVMIRPlatform(LLJIT &J);
+
 public:
-  static Expected<std::unique_ptr<LLJIT>> Create(LLJITBuilderState &S);
+  /// Initializer support for LLJIT.
+  class PlatformSupport {
+  public:
+    virtual ~PlatformSupport();
+
+    virtual Error initialize(JITDylib &JD) = 0;
+
+    virtual Error deinitialize(JITDylib &JD) = 0;
+
+  protected:
+    static void setInitTransform(LLJIT &J,
+                                 IRTransformLayer::TransformFunction T);
+  };
 
   /// Destruct this instance. If a multi-threaded instance, waits for all
   /// compile threads to complete.
@@ -45,11 +61,14 @@
   /// Returns the ExecutionSession for this instance.
   ExecutionSession &getExecutionSession() { return *ES; }
 
+  /// Returns a reference to the triple for this instance.
+  const Triple &getTargetTriple() const { return TT; }
+
   /// Returns a reference to the DataLayout for this instance.
   const DataLayout &getDataLayout() const { return DL; }
 
   /// Returns a reference to the JITDylib representing the JIT'd main program.
-  JITDylib &getMainJITDylib() { return Main; }
+  JITDylib &getMainJITDylib() { return *Main; }
 
   /// Returns the JITDylib with the given name, or nullptr if no JITDylib with
   /// that name exists.
@@ -63,39 +82,49 @@
   /// input or elsewhere in the environment then the client should check
   /// (e.g. by calling getJITDylibByName) that the given name is not already in
   /// use.
-  JITDylib &createJITDylib(std::string Name) {
+  Expected<JITDylib &> createJITDylib(std::string Name) {
     return ES->createJITDylib(std::move(Name));
   }
 
-  /// Convenience method for defining an absolute symbol.
-  Error defineAbsolute(StringRef Name, JITEvaluatedSymbol Address);
+  /// Adds an IR module with the given ResourceTracker.
+  Error addIRModule(ResourceTrackerSP RT, ThreadSafeModule TSM);
 
   /// Adds an IR module to the given JITDylib.
   Error addIRModule(JITDylib &JD, ThreadSafeModule TSM);
 
   /// Adds an IR module to the Main JITDylib.
   Error addIRModule(ThreadSafeModule TSM) {
-    return addIRModule(Main, std::move(TSM));
+    return addIRModule(*Main, std::move(TSM));
   }
 
   /// Adds an object file to the given JITDylib.
+  Error addObjectFile(ResourceTrackerSP RT, std::unique_ptr<MemoryBuffer> Obj);
+
+  /// Adds an object file to the given JITDylib.
   Error addObjectFile(JITDylib &JD, std::unique_ptr<MemoryBuffer> Obj);
 
   /// Adds an object file to the given JITDylib.
   Error addObjectFile(std::unique_ptr<MemoryBuffer> Obj) {
-    return addObjectFile(Main, std::move(Obj));
+    return addObjectFile(*Main, std::move(Obj));
   }
 
   /// Look up a symbol in JITDylib JD by the symbol's linker-mangled name (to
   /// look up symbols based on their IR name use the lookup function instead).
   Expected<JITEvaluatedSymbol> lookupLinkerMangled(JITDylib &JD,
-                                                   StringRef Name);
+                                                   SymbolStringPtr Name);
+
+  /// Look up a symbol in JITDylib JD by the symbol's linker-mangled name (to
+  /// look up symbols based on their IR name use the lookup function instead).
+  Expected<JITEvaluatedSymbol> lookupLinkerMangled(JITDylib &JD,
+                                                   StringRef Name) {
+    return lookupLinkerMangled(JD, ES->intern(Name));
+  }
 
   /// Look up a symbol in the main JITDylib by the symbol's linker-mangled name
   /// (to look up symbols based on their IR name use the lookup function
   /// instead).
   Expected<JITEvaluatedSymbol> lookupLinkerMangled(StringRef Name) {
-    return lookupLinkerMangled(Main, Name);
+    return lookupLinkerMangled(*Main, Name);
   }
 
   /// Look up a symbol in JITDylib JD based on its IR symbol name.
@@ -105,41 +134,85 @@
 
   /// Look up a symbol in the main JITDylib based on its IR symbol name.
   Expected<JITEvaluatedSymbol> lookup(StringRef UnmangledName) {
-    return lookup(Main, UnmangledName);
+    return lookup(*Main, UnmangledName);
   }
 
-  /// Runs all not-yet-run static constructors.
-  Error runConstructors() { return CtorRunner.run(); }
+  /// Set the PlatformSupport instance.
+  void setPlatformSupport(std::unique_ptr<PlatformSupport> PS) {
+    this->PS = std::move(PS);
+  }
 
-  /// Runs all not-yet-run static destructors.
-  Error runDestructors() { return DtorRunner.run(); }
+  /// Get the PlatformSupport instance.
+  PlatformSupport *getPlatformSupport() { return PS.get(); }
+
+  /// Run the initializers for the given JITDylib.
+  Error initialize(JITDylib &JD) {
+    DEBUG_WITH_TYPE("orc", {
+      dbgs() << "LLJIT running initializers for JITDylib \"" << JD.getName()
+             << "\"\n";
+    });
+    assert(PS && "PlatformSupport must be set to run initializers.");
+    return PS->initialize(JD);
+  }
+
+  /// Run the deinitializers for the given JITDylib.
+  Error deinitialize(JITDylib &JD) {
+    DEBUG_WITH_TYPE("orc", {
+      dbgs() << "LLJIT running deinitializers for JITDylib \"" << JD.getName()
+             << "\"\n";
+    });
+    assert(PS && "PlatformSupport must be set to run initializers.");
+    return PS->deinitialize(JD);
+  }
 
   /// Returns a reference to the ObjLinkingLayer
   ObjectLayer &getObjLinkingLayer() { return *ObjLinkingLayer; }
 
+  /// Returns a reference to the object transform layer.
+  ObjectTransformLayer &getObjTransformLayer() { return *ObjTransformLayer; }
+
+  /// Returns a reference to the IR transform layer.
+  IRTransformLayer &getIRTransformLayer() { return *TransformLayer; }
+
+  /// Returns a reference to the IR compile layer.
+  IRCompileLayer &getIRCompileLayer() { return *CompileLayer; }
+
+  /// Returns a linker-mangled version of UnmangledName.
+  std::string mangle(StringRef UnmangledName) const;
+
+  /// Returns an interned, linker-mangled version of UnmangledName.
+  SymbolStringPtr mangleAndIntern(StringRef UnmangledName) const {
+    return ES->intern(mangle(UnmangledName));
+  }
+
 protected:
-  static std::unique_ptr<ObjectLayer>
+  static Expected<std::unique_ptr<ObjectLayer>>
   createObjectLinkingLayer(LLJITBuilderState &S, ExecutionSession &ES);
 
+  static Expected<std::unique_ptr<IRCompileLayer::IRCompiler>>
+  createCompileFunction(LLJITBuilderState &S, JITTargetMachineBuilder JTMB);
+
   /// Create an LLJIT instance with a single compile thread.
   LLJIT(LLJITBuilderState &S, Error &Err);
 
-  std::string mangle(StringRef UnmangledName);
-
   Error applyDataLayout(Module &M);
 
   void recordCtorDtors(Module &M);
 
   std::unique_ptr<ExecutionSession> ES;
-  JITDylib &Main;
+  std::unique_ptr<PlatformSupport> PS;
+
+  JITDylib *Main = nullptr;
 
   DataLayout DL;
+  Triple TT;
   std::unique_ptr<ThreadPool> CompileThreads;
 
   std::unique_ptr<ObjectLayer> ObjLinkingLayer;
+  std::unique_ptr<ObjectTransformLayer> ObjTransformLayer;
   std::unique_ptr<IRCompileLayer> CompileLayer;
-
-  CtorDtorRunner CtorRunner, DtorRunner;
+  std::unique_ptr<IRTransformLayer> TransformLayer;
+  std::unique_ptr<IRTransformLayer> InitHelperTransformLayer;
 };
 
 /// An extended version of LLJIT that supports lazy function-at-a-time
@@ -149,24 +222,21 @@
 
 public:
 
-  /// Set an IR transform (e.g. pass manager pipeline) to run on each function
-  /// when it is compiled.
-  void setLazyCompileTransform(IRTransformLayer::TransformFunction Transform) {
-    TransformLayer->setTransform(std::move(Transform));
-  }
-
   /// Sets the partition function.
   void
   setPartitionFunction(CompileOnDemandLayer::PartitionFunction Partition) {
     CODLayer->setPartitionFunction(std::move(Partition));
   }
 
+  /// Returns a reference to the on-demand layer.
+  CompileOnDemandLayer &getCompileOnDemandLayer() { return *CODLayer; }
+
   /// Add a module to be lazily compiled to JITDylib JD.
   Error addLazyIRModule(JITDylib &JD, ThreadSafeModule M);
 
   /// Add a module to be lazily compiled to the main JITDylib.
   Error addLazyIRModule(ThreadSafeModule M) {
-    return addLazyIRModule(Main, std::move(M));
+    return addLazyIRModule(*Main, std::move(M));
   }
 
 private:
@@ -175,19 +245,29 @@
   LLLazyJIT(LLLazyJITBuilderState &S, Error &Err);
 
   std::unique_ptr<LazyCallThroughManager> LCTMgr;
-  std::unique_ptr<IRTransformLayer> TransformLayer;
   std::unique_ptr<CompileOnDemandLayer> CODLayer;
 };
 
 class LLJITBuilderState {
 public:
-  using CreateObjectLinkingLayerFunction =
-      std::function<std::unique_ptr<ObjectLayer>(ExecutionSession &)>;
+  using ObjectLinkingLayerCreator =
+      std::function<Expected<std::unique_ptr<ObjectLayer>>(ExecutionSession &,
+                                                           const Triple &)>;
+
+  using CompileFunctionCreator =
+      std::function<Expected<std::unique_ptr<IRCompileLayer::IRCompiler>>(
+          JITTargetMachineBuilder JTMB)>;
+
+  using PlatformSetupFunction = std::function<Error(LLJIT &J)>;
 
   std::unique_ptr<ExecutionSession> ES;
   Optional<JITTargetMachineBuilder> JTMB;
-  CreateObjectLinkingLayerFunction CreateObjectLinkingLayer;
+  Optional<DataLayout> DL;
+  ObjectLinkingLayerCreator CreateObjectLinkingLayer;
+  CompileFunctionCreator CreateCompileFunction;
+  PlatformSetupFunction SetUpPlatform;
   unsigned NumCompileThreads = 0;
+  TargetProcessControl *TPC = nullptr;
 
   /// Called prior to JIT class construcion to fix up defaults.
   Error prepareForConstruction();
@@ -196,6 +276,13 @@
 template <typename JITType, typename SetterImpl, typename State>
 class LLJITBuilderSetters {
 public:
+
+  /// Set an ExecutionSession for this instance.
+  SetterImpl &setExecutionSession(std::unique_ptr<ExecutionSession> ES) {
+    impl().ES = std::move(ES);
+    return impl();
+  }
+
   /// Set the JITTargetMachineBuilder for this instance.
   ///
   /// If this method is not called, JITTargetMachineBuilder::detectHost will be
@@ -211,17 +298,45 @@
     return impl().JTMB;
   }
 
+  /// Set a DataLayout for this instance. If no data layout is specified then
+  /// the target's default data layout will be used.
+  SetterImpl &setDataLayout(Optional<DataLayout> DL) {
+    impl().DL = std::move(DL);
+    return impl();
+  }
+
   /// Set an ObjectLinkingLayer creation function.
   ///
   /// If this method is not called, a default creation function will be used
   /// that will construct an RTDyldObjectLinkingLayer.
-  SetterImpl &setCreateObjectLinkingLayer(
-      LLJITBuilderState::CreateObjectLinkingLayerFunction
-          CreateObjectLinkingLayer) {
+  SetterImpl &setObjectLinkingLayerCreator(
+      LLJITBuilderState::ObjectLinkingLayerCreator CreateObjectLinkingLayer) {
     impl().CreateObjectLinkingLayer = std::move(CreateObjectLinkingLayer);
     return impl();
   }
 
+  /// Set a CompileFunctionCreator.
+  ///
+  /// If this method is not called, a default creation function wil be used
+  /// that will construct a basic IR compile function that is compatible with
+  /// the selected number of threads (SimpleCompiler for '0' compile threads,
+  /// ConcurrentIRCompiler otherwise).
+  SetterImpl &setCompileFunctionCreator(
+      LLJITBuilderState::CompileFunctionCreator CreateCompileFunction) {
+    impl().CreateCompileFunction = std::move(CreateCompileFunction);
+    return impl();
+  }
+
+  /// Set up an PlatformSetupFunction.
+  ///
+  /// If this method is not called then setUpGenericLLVMIRPlatform
+  /// will be used to configure the JIT's platform support.
+  SetterImpl &
+  setPlatformSetUp(LLJITBuilderState::PlatformSetupFunction SetUpPlatform) {
+    impl().SetUpPlatform = std::move(SetUpPlatform);
+    return impl();
+  }
+
   /// Set the number of compile threads to use.
   ///
   /// If set to zero, compilation will be performed on the execution thread when
@@ -235,6 +350,17 @@
     return impl();
   }
 
+  /// Set a TargetProcessControl object.
+  ///
+  /// If the platform uses ObjectLinkingLayer by default and no
+  /// ObjectLinkingLayerCreator has been set then the TargetProcessControl
+  /// object will be used to supply the memory manager for the
+  /// ObjectLinkingLayer.
+  SetterImpl &setTargetProcessControl(TargetProcessControl &TPC) {
+    impl().TPC = &TPC;
+    return impl();
+  }
+
   /// Create an instance of the JIT.
   Expected<std::unique_ptr<JITType>> create() {
     if (auto Err = impl().prepareForConstruction())
@@ -310,6 +436,26 @@
       public LLLazyJITBuilderSetters<LLLazyJIT, LLLazyJITBuilder,
                                      LLLazyJITBuilderState> {};
 
+/// Configure the LLJIT instance to scrape modules for llvm.global_ctors and
+/// llvm.global_dtors variables and (if present) build initialization and
+/// deinitialization functions. Platform specific initialization configurations
+/// should be preferred where available.
+void setUpGenericLLVMIRPlatform(LLJIT &J);
+
+/// Configure the LLJIT instance to use MachOPlatform support.
+///
+/// Warning: MachOPlatform *requires* that LLJIT be configured to use
+/// ObjectLinkingLayer (default on platforms supported by JITLink). If
+/// MachOPlatform is used with RTDyldObjectLinkingLayer it will result in
+/// undefined behavior).
+///
+/// MachOPlatform installs an ObjectLinkingLayer plugin to scrape initializers
+/// from the __mod_inits section. It also provides interposes for the dlfcn
+/// functions (dlopen, dlclose, dlsym, dlerror) that work for JITDylibs as
+/// well as regular libraries (JITDylibs will be preferenced, so make sure
+/// your JITDylib names do not shadow any real library paths).
+Error setUpMachOPlatform(LLJIT &J);
+
 } // End namespace orc
 } // End namespace llvm