lldb/source/Plugins/ABI/AArch64/ABISysV_arm64.h

   1 //===-- ABISysV_arm64.h ---------------------------------------*- C++ -*-===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #ifndef LLDB_SOURCE_PLUGINS_ABI_AARCH64_ABISYSV_ARM64_H
  10 #define LLDB_SOURCE_PLUGINS_ABI_AARCH64_ABISYSV_ARM64_H
  11
  12 #include "Plugins/ABI/AArch64/ABIAArch64.h"
  13 #include "lldb/lldb-private.h"
  14
  15 class ABISysV_arm64 : public ABIAArch64 {
  16 public:
  17   ~ABISysV_arm64() override = default;
  18
  19   size_t GetRedZoneSize() const override;
  20
  21   bool PrepareTrivialCall(lldb_private::Thread &thread, lldb::addr_t sp,
  22                           lldb::addr_t functionAddress,
  23                           lldb::addr_t returnAddress,
  24                           llvm::ArrayRef<lldb::addr_t> args) const override;
  25
  26   bool GetArgumentValues(lldb_private::Thread &thread,
  27                          lldb_private::ValueList &values) const override;
  28
  29   lldb_private::Status
  30   SetReturnValueObject(lldb::StackFrameSP &frame_sp,
  31                        lldb::ValueObjectSP &new_value) override;
  32
  33   bool
  34   CreateFunctionEntryUnwindPlan(lldb_private::UnwindPlan &unwind_plan) override;
  35
  36   bool CreateDefaultUnwindPlan(lldb_private::UnwindPlan &unwind_plan) override;
  37
  38   bool RegisterIsVolatile(const lldb_private::RegisterInfo *reg_info) override;
  39
  40   // The arm64 ABI requires that stack frames be 16 byte aligned.
  41   // When there is a trap handler on the stack, e.g. _sigtramp in userland
  42   // code, we've seen that the stack pointer is often not aligned properly
  43   // before the handler is invoked.  This means that lldb will stop the unwind
  44   // early -- before the function which caused the trap.
  45   //
  46   // To work around this, we relax that alignment to be just word-size
  47   // (8-bytes).
  48   // Allowing the trap handlers for user space would be easy (_sigtramp) but
  49   // in other environments there can be a large number of different functions
  50   // involved in async traps.
  51   bool CallFrameAddressIsValid(lldb::addr_t cfa) override {
  52     // Make sure the stack call frame addresses are 8 byte aligned
  53     if (cfa & (8ull - 1ull))
  54       return false; // Not 8 byte aligned
  55     if (cfa == 0)
  56       return false; // Zero is not a valid stack address
  57     return true;
  58   }
  59
  60   bool CodeAddressIsValid(lldb::addr_t pc) override {
  61     if (pc & (4ull - 1ull))
  62       return false; // Not 4 byte aligned
  63
  64     // Anything else if fair game..
  65     return true;
  66   }
  67
  68   bool GetPointerReturnRegister(const char *&name) override;
  69
  70   lldb::addr_t FixAddress(lldb::addr_t pc, lldb::addr_t mask) override;
  71
  72   // Static Functions
  73
  74   static void Initialize();
  75
  76   static void Terminate();
  77
  78   static lldb::ABISP CreateInstance(lldb::ProcessSP process_sp, const lldb_private::ArchSpec &arch);
  79
  80   static llvm::StringRef GetPluginNameStatic() { return "SysV-arm64"; }
  81
  82   // PluginInterface protocol
  83
  84   llvm::StringRef GetPluginName() override { return GetPluginNameStatic(); }
  85
  86   lldb::addr_t FixCodeAddress(lldb::addr_t pc) override;
  87   lldb::addr_t FixDataAddress(lldb::addr_t pc) override;
  88
  89 protected:
  90   lldb::ValueObjectSP
  91   GetReturnValueObjectImpl(lldb_private::Thread &thread,
  92                            lldb_private::CompilerType &ast_type) const override;
  93
  94 private:
  95   using ABIAArch64::ABIAArch64; // Call CreateInstance instead.
  96 };
  97
  98 #endif // LLDB_SOURCE_PLUGINS_ABI_AARCH64_ABISYSV_ARM64_H