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ABIMacOSX_i386.h
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1 //===-- ABIMacOSX_i386.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_ABIMacOSX_i386_h_
10 #define liblldb_ABIMacOSX_i386_h_
11 
12 #include "lldb/Core/Value.h"
13 #include "lldb/Target/ABI.h"
14 #include "lldb/lldb-private.h"
15 
17 public:
18  ~ABIMacOSX_i386() override = default;
19 
20  size_t GetRedZoneSize() const override;
21 
23  lldb::addr_t func_addr, lldb::addr_t return_addr,
24  llvm::ArrayRef<lldb::addr_t> args) const override;
25 
27  lldb_private::ValueList &values) const override;
28 
30  SetReturnValueObject(lldb::StackFrameSP &frame_sp,
31  lldb::ValueObjectSP &new_value) override;
32 
33  bool
35 
36  bool CreateDefaultUnwindPlan(lldb_private::UnwindPlan &unwind_plan) override;
37 
38  bool RegisterIsVolatile(const lldb_private::RegisterInfo *reg_info) override;
39 
40  // The Darwin i386 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  // (4-bytes).
48  // Whitelisting 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  //
52  // If we were to enforce 16-byte alignment, we also need to relax to 4-byte
53  // alignment for non-darwin i386 targets.
55  // Make sure the stack call frame addresses are are 4 byte aligned
56  if (cfa & (4ull - 1ull))
57  return false; // Not 4 byte aligned
58  if (cfa == 0)
59  return false; // Zero is not a valid stack address
60  return true;
61  }
62 
64  // Just make sure the address is a valid 32 bit address.
65  return pc <= UINT32_MAX;
66  }
67 
68  const lldb_private::RegisterInfo *
69  GetRegisterInfoArray(uint32_t &count) override;
70 
71  // Static Functions
72 
73  static void Initialize();
74 
75  static void Terminate();
76 
77  static lldb::ABISP CreateInstance(lldb::ProcessSP process_sp, const lldb_private::ArchSpec &arch);
78 
79  // PluginInterface protocol
80 
82 
84 
85  uint32_t GetPluginVersion() override;
86 
87 protected:
88  lldb::ValueObjectSP
90  lldb_private::CompilerType &ast_type) const override;
91 
92  bool RegisterIsCalleeSaved(const lldb_private::RegisterInfo *reg_info);
93 
94 private:
95  ABIMacOSX_i386(lldb::ProcessSP process_sp) : lldb_private::ABI(process_sp) {
96  // Call CreateInstance instead.
97  }
98 };
99 
100 #endif // liblldb_ABIMacOSX_i386_h_
static void Terminate()
static lldb::ABISP CreateInstance(lldb::ProcessSP process_sp, const lldb_private::ArchSpec &arch)
lldb_private::ConstString GetPluginName() override
uint32_t GetPluginVersion() override
An architecture specification class.
Definition: ArchSpec.h:32
~ABIMacOSX_i386() override=default
bool PrepareTrivialCall(lldb_private::Thread &thread, lldb::addr_t sp, lldb::addr_t func_addr, lldb::addr_t return_addr, llvm::ArrayRef< lldb::addr_t > args) const override
#define UINT32_MAX
Definition: lldb-defines.h:31
lldb_private::Status SetReturnValueObject(lldb::StackFrameSP &frame_sp, lldb::ValueObjectSP &new_value) override
static lldb_private::ConstString GetPluginNameStatic()
bool GetArgumentValues(lldb_private::Thread &thread, lldb_private::ValueList &values) const override
bool RegisterIsCalleeSaved(const lldb_private::RegisterInfo *reg_info)
size_t GetRedZoneSize() const override
const lldb_private::RegisterInfo * GetRegisterInfoArray(uint32_t &count) override
bool CreateDefaultUnwindPlan(lldb_private::UnwindPlan &unwind_plan) override
bool CreateFunctionEntryUnwindPlan(lldb_private::UnwindPlan &unwind_plan) override
uint64_t addr_t
Definition: lldb-types.h:83
bool RegisterIsVolatile(const lldb_private::RegisterInfo *reg_info) override
A uniqued constant string class.
Definition: ConstString.h:38
bool CallFrameAddressIsValid(lldb::addr_t cfa) override
bool CodeAddressIsValid(lldb::addr_t pc) override
lldb::ValueObjectSP GetReturnValueObjectImpl(lldb_private::Thread &thread, lldb_private::CompilerType &ast_type) const override
static void Initialize()
An error handling class.
Definition: Status.h:44