ABISysV_ppc.h revision 360784 
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 liblldb_ABISysV_ppc_h_
10#define liblldb_ABISysV_ppc_h_
11
12#include "lldb/Target/ABI.h"
13#include "lldb/lldb-private.h"
14
15class ABISysV_ppc : public lldb_private::ABI {
16public:
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  // Whitelisting 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 lldb_private::ConstString GetPluginNameStatic();
82
83  // PluginInterface protocol
84
85  lldb_private::ConstString GetPluginName() override;
86
87  uint32_t GetPluginVersion() override;
88
89protected:
90  void CreateRegisterMapIfNeeded();
91
92  lldb::ValueObjectSP
93  GetReturnValueObjectSimple(lldb_private::Thread &thread,
94                             lldb_private::CompilerType &ast_type) const;
95
96  bool RegisterIsCalleeSaved(const lldb_private::RegisterInfo *reg_info);
97
98private:
99  ABISysV_ppc(lldb::ProcessSP process_sp,
100              std::unique_ptr<llvm::MCRegisterInfo> info_up)
101      : lldb_private::ABI(std::move(process_sp), std::move(info_up)) {
102    // Call CreateInstance instead.
103  }
104};
105
106#endif // liblldb_ABISysV_ppc_h_
107