[ORC] Introduce EPCGenericRTDyldMemoryManager.

EPCGenericRTDyldMemoryMnaager is an EPC-based implementation of the
RuntimeDyld::MemoryManager interface. It enables remote-JITing via EPC (backed
by a SimpleExecutorMemoryManager instance on the executor side) for RuntimeDyld
clients.

The lli and lli-child-target tools are updated to use SimpleRemoteEPC and
SimpleRemoteEPCServer (rather than OrcRemoteTargetClient/Server), and
EPCGenericRTDyldMemoryManager for MCJIT tests.

By enabling remote-JITing for MCJIT and RuntimeDyld-based ORC clients,
EPCGenericRTDyldMemoryManager allows us to deprecate older remote-JITing
support, including OrcTargetClient/Server, OrcRPCExecutorProcessControl, and the
Orc RPC system itself. These will be removed in future patches.

Author: lhames

llvm/include/llvm/ExecutionEngine/Orc/EPCGenericRTDyldMemoryManager.h

@@ -0,0 +1,133 @@
+//===---- EPCGenericRTDyldMemoryManager.h - EPC-based MemMgr ----*- C++ -*-===//
+//
+// 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
+//
+//===----------------------------------------------------------------------===//
+//
+// Defines a RuntimeDyld::MemoryManager that uses EPC and the ORC runtime
+// bootstrap functions.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_EXECUTIONENGINE_ORC_EPCGENERICRTDYLDMEMORYMANAGER_H
+#define LLVM_EXECUTIONENGINE_ORC_EPCGENERICRTDYLDMEMORYMANAGER_H
+
+#include "llvm/ExecutionEngine/Orc/ExecutorProcessControl.h"
+#include "llvm/ExecutionEngine/RuntimeDyld.h"
+
+#define DEBUG_TYPE "orc"
+
+namespace llvm {
+namespace orc {
+
+/// Remote-mapped RuntimeDyld-compatible memory manager.
+class EPCGenericRTDyldMemoryManager : public RuntimeDyld::MemoryManager {
+public:
+  /// Symbol addresses for memory access.
+  struct SymbolAddrs {
+    ExecutorAddr Instance;
+    ExecutorAddr Reserve;
+    ExecutorAddr Finalize;
+    ExecutorAddr Deallocate;
+    ExecutorAddr RegisterEHFrame;
+    ExecutorAddr DeregisterEHFrame;
+  };
+
+  /// Create an EPCGenericRTDyldMemoryManager using the given EPC, looking up
+  /// the default symbol names in the bootstrap symbol set.
+  static Expected<std::unique_ptr<EPCGenericRTDyldMemoryManager>>
+  CreateWithDefaultBootstrapSymbols(ExecutorProcessControl &EPC);
+
+  /// Create an EPCGenericRTDyldMemoryManager using the given EPC and symbol
+  /// addrs.
+  EPCGenericRTDyldMemoryManager(ExecutorProcessControl &EPC, SymbolAddrs SAs);
+
+  EPCGenericRTDyldMemoryManager(const EPCGenericRTDyldMemoryManager &) = delete;
+  EPCGenericRTDyldMemoryManager &
+  operator=(const EPCGenericRTDyldMemoryManager &) = delete;
+  EPCGenericRTDyldMemoryManager(EPCGenericRTDyldMemoryManager &&) = delete;
+  EPCGenericRTDyldMemoryManager &
+  operator=(EPCGenericRTDyldMemoryManager &&) = delete;
+  ~EPCGenericRTDyldMemoryManager();
+
+  uint8_t *allocateCodeSection(uintptr_t Size, unsigned Alignment,
+                               unsigned SectionID,
+                               StringRef SectionName) override;
+
+  uint8_t *allocateDataSection(uintptr_t Size, unsigned Alignment,
+                               unsigned SectionID, StringRef SectionName,
+                               bool IsReadOnly) override;
+
+  void reserveAllocationSpace(uintptr_t CodeSize, uint32_t CodeAlign,
+                              uintptr_t RODataSize, uint32_t RODataAlign,
+                              uintptr_t RWDataSize,
+                              uint32_t RWDataAlign) override;
+
+  bool needsToReserveAllocationSpace() override;
+
+  void registerEHFrames(uint8_t *Addr, uint64_t LoadAddr, size_t Size) override;
+
+  void deregisterEHFrames() override;
+
+  void notifyObjectLoaded(RuntimeDyld &Dyld,
+                          const object::ObjectFile &Obj) override;
+
+  bool finalizeMemory(std::string *ErrMsg = nullptr) override;
+
+private:
+  struct Alloc {
+  public:
+    Alloc(uint64_t Size, unsigned Align)
+        : Size(Size), Align(Align),
+          Contents(std::make_unique<uint8_t[]>(Size + Align - 1)) {}
+
+    uint64_t Size;
+    unsigned Align;
+    std::unique_ptr<uint8_t[]> Contents;
+    ExecutorAddr RemoteAddr;
+  };
+
+  struct EHFrame {
+    ExecutorAddr Addr;
+    uint64_t Size;
+  };
+
+  // Group of section allocations to be allocated together in the executor. The
+  // RemoteCodeAddr will stand in as the id of the group for deallocation
+  // purposes.
+  struct AllocGroup {
+    AllocGroup() = default;
+    AllocGroup(const AllocGroup &) = delete;
+    AllocGroup &operator=(const AllocGroup &) = delete;
+    AllocGroup(AllocGroup &&) = default;
+    AllocGroup &operator=(AllocGroup &&) = default;
+
+    ExecutorAddrRange RemoteCode;
+    ExecutorAddrRange RemoteROData;
+    ExecutorAddrRange RemoteRWData;
+    std::vector<EHFrame> UnfinalizedEHFrames;
+    std::vector<Alloc> CodeAllocs, RODataAllocs, RWDataAllocs;
+  };
+
+  // Maps all allocations in Allocs to aligned blocks
+  void mapAllocsToRemoteAddrs(RuntimeDyld &Dyld, std::vector<Alloc> &Allocs,
+                              ExecutorAddr NextAddr);
+
+  ExecutorProcessControl &EPC;
+  SymbolAddrs SAs;
+
+  std::mutex M;
+  std::vector<AllocGroup> Unmapped;
+  std::vector<AllocGroup> Unfinalized;
+  std::vector<ExecutorAddr> FinalizedAllocs;
+  std::string ErrMsg;
+};
+
+} // end namespace orc
+} // end namespace llvm
+
+#undef DEBUG_TYPE
+
+#endif // LLVM_EXECUTIONENGINE_ORC_EPCGENERICRTDYLDMEMORYMANAGER_H

llvm/include/llvm/ExecutionEngine/Orc/Shared/OrcRTBridge.h

@@ -37,6 +37,9 @@ extern const char *MemoryWriteUInt32sWrapperName;
 extern const char *MemoryWriteUInt64sWrapperName;
 extern const char *MemoryWriteBuffersWrapperName;
 
+extern const char *RegisterEHFrameSectionCustomDirectWrapperName;
+extern const char *DeregisterEHFrameSectionCustomDirectWrapperName;
+
 extern const char *RunAsMainWrapperName;
 
 using SPSSimpleExecutorDylibManagerOpenSignature =

llvm/include/llvm/ExecutionEngine/Orc/TargetProcess/RegisterEHFrames.h

@@ -33,6 +33,22 @@ Error deregisterEHFrameSection(const void *EHFrameSectionAddr,
 } // end namespace orc
 } // end namespace llvm
 
+/// An eh-frame registration utility suitable for use as a support function
+/// call. This function expects the direct address and size of the eh-frame
+/// section to register as its arguments (it does not treat its arguments as
+/// pointers to an SPS-serialized arg buffer).
+extern "C" llvm::orc::shared::detail::CWrapperFunctionResult
+llvm_orc_registerEHFrameSectionCustomDirectWrapper(
+    const char *EHFrameSectionAddr, uint64_t Size);
+
+/// An eh-frame deregistration utility suitable for use as a support function
+/// call. This function expects the direct address and size of the eh-frame
+/// section to register as its arguments (it does not treat its arguments as
+/// pointers to an SPS-serialized arg buffer).
+extern "C" llvm::orc::shared::detail::CWrapperFunctionResult
+llvm_orc_deregisterEHFrameSectionCustomDirectWrapper(
+    const char *EHFrameSectionAddr, uint64_t Size);
+
 extern "C" llvm::orc::shared::detail::CWrapperFunctionResult
 llvm_orc_registerEHFrameSectionWrapper(const char *Data, uint64_t Size);
 

llvm/lib/ExecutionEngine/Orc/CMakeLists.txt

@@ -9,6 +9,7 @@ add_llvm_component_library(LLVMOrcJIT
   EPCEHFrameRegistrar.cpp
   EPCGenericDylibManager.cpp
   EPCGenericJITLinkMemoryManager.cpp
+  EPCGenericRTDyldMemoryManager.cpp
   EPCIndirectionUtils.cpp
   ExecutionUtils.cpp
   IndirectionUtils.cpp