lldb/source/Plugins/ABI/PowerPC/ABISysV_ppc.h

   1 //===-- ABISysV_ppc.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_POWERPC_ABISYSV_PPC_H
  10 #define LLDB_SOURCE_PLUGINS_ABI_POWERPC_ABISYSV_PPC_H
  11
  12 #include "lldb/Target/ABI.h"
  13 #include "lldb/lldb-private.h"
  14
  15 class ABISysV_ppc : public lldb_private::RegInfoBasedABI {
  16 public:
  17   ~ABISysV_ppc() 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   lldb::ValueObjectSP
  34   GetReturnValueObjectImpl(lldb_private::Thread &thread,
  35                            lldb_private::CompilerType &type) const override;
  36
  37   bool
  38   CreateFunctionEntryUnwindPlan(lldb_private::UnwindPlan &unwind_plan) override;
  39
  40   bool CreateDefaultUnwindPlan(lldb_private::UnwindPlan &unwind_plan) override;
  41
  42   bool RegisterIsVolatile(const lldb_private::RegisterInfo *reg_info) override;
  43
  44   // The SysV ppc ABI requires that stack frames be 16 byte aligned.
  45   // When there is a trap handler on the stack, e.g. _sigtramp in userland
  46   // code, we've seen that the stack pointer is often not aligned properly
  47   // before the handler is invoked.  This means that lldb will stop the unwind
  48   // early -- before the function which caused the trap.
  49   //
  50   // To work around this, we relax that alignment to be just word-size
  51   // (8-bytes).
  52   // Allowing the trap handlers for user space would be easy (_sigtramp) but
  53   // in other environments there can be a large number of different functions
  54   // involved in async traps.
  55   bool CallFrameAddressIsValid(lldb::addr_t cfa) override {
  56     // Make sure the stack call frame addresses are 8 byte aligned
  57     if (cfa & (8ull - 1ull))
  58       return false; // Not 8 byte aligned
  59     if (cfa == 0)
  60       return false; // Zero is not a valid stack address
  61     return true;
  62   }
  63
  64   bool CodeAddressIsValid(lldb::addr_t pc) override {
  65     // We have a 64 bit address space, so anything is valid as opcodes
  66     // aren't fixed width...
  67     return true;
  68   }
  69
  70   const lldb_private::RegisterInfo *
  71   GetRegisterInfoArray(uint32_t &count) override;
  72
  73   // Static Functions
  74
  75   static void Initialize();
  76
  77   static void Terminate();
  78
  79   static lldb::ABISP CreateInstance(lldb::ProcessSP process_sp, const lldb_private::ArchSpec &arch);
  80
  81   static llvm::StringRef GetPluginNameStatic() { return "sysv-ppc"; }
  82
  83   // PluginInterface protocol
  84
  85   llvm::StringRef GetPluginName() override { return GetPluginNameStatic(); }
  86
  87 protected:
  88   void CreateRegisterMapIfNeeded();
  89
  90   lldb::ValueObjectSP
  91   GetReturnValueObjectSimple(lldb_private::Thread &thread,
  92                              lldb_private::CompilerType &ast_type) const;
  93
  94   bool RegisterIsCalleeSaved(const lldb_private::RegisterInfo *reg_info);
  95
  96 private:
  97   using lldb_private::RegInfoBasedABI::RegInfoBasedABI; // Call CreateInstance instead.
  98 };
  99
 100 #endif // LLDB_SOURCE_PLUGINS_ABI_POWERPC_ABISYSV_PPC_H