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ABISysV_i386.h
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1 //===------------------- ABISysV_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_ABISysV_i386_h_
10 #define liblldb_ABISysV_i386_h_
11 
12 #include "lldb/Target/ABI.h"
13 #include "lldb/lldb-private.h"
14 
16 public:
17  ~ABISysV_i386() override = default;
18 
19  size_t GetRedZoneSize() const override {
20  return 0; // There is no red zone for i386 Architecture
21  }
22 
24  lldb::addr_t functionAddress,
25  lldb::addr_t returnAddress,
26  llvm::ArrayRef<lldb::addr_t> args) const override;
27 
29  lldb_private::ValueList &values) const override;
30 
32  SetReturnValueObject(lldb::StackFrameSP &frame_sp,
33  lldb::ValueObjectSP &new_value) override;
34 
35  lldb::ValueObjectSP
37  lldb_private::CompilerType &type) const override;
38 
39  bool
41 
42  bool CreateDefaultUnwindPlan(lldb_private::UnwindPlan &unwind_plan) override;
43 
44  bool RegisterIsVolatile(const lldb_private::RegisterInfo *reg_info) override {
45  return !RegisterIsCalleeSaved(reg_info);
46  }
47 
48  // The SysV i386 ABI requires that stack frames be 16 byte aligned.
49  // When there is a trap handler on the stack, e.g. _sigtramp in userland
50  // code, we've seen that the stack pointer is often not aligned properly
51  // before the handler is invoked. This means that lldb will stop the unwind
52  // early -- before the function which caused the trap.
53  //
54  // To work around this, we relax that alignment to be just word-size
55  // (4-bytes).
56  // Whitelisting the trap handlers for user space would be easy (_sigtramp) but
57  // in other environments there can be a large number of different functions
58  // involved in async traps.
59 
60  // ToDo: When __m256 arguments are passed then stack frames should be
61  // 32 byte aligned. Decide what to do for 32 byte alignment checking
63  // Make sure the stack call frame addresses are 4 byte aligned
64  if (cfa & (4ull - 1ull))
65  return false; // Not 4 byte aligned
66  if (cfa == 0)
67  return false; // Zero is not a valid stack address
68  return true;
69  }
70 
72  // Check whether the address is a valid 32 bit address
73  return (pc <= UINT32_MAX);
74  }
75 
76  const lldb_private::RegisterInfo *
77  GetRegisterInfoArray(uint32_t &count) override;
78 
79  // Static Functions
80 
81  static void Initialize();
82 
83  static void Terminate();
84 
85  static lldb::ABISP CreateInstance(lldb::ProcessSP process_sp, const lldb_private::ArchSpec &arch);
86 
87  // PluginInterface protocol
88 
90 
92 
93  uint32_t GetPluginVersion() override { return 1; }
94 
95 protected:
96  lldb::ValueObjectSP
98  lldb_private::CompilerType &ast_type) const;
99 
100  bool RegisterIsCalleeSaved(const lldb_private::RegisterInfo *reg_info);
101 
102 private:
103  ABISysV_i386(lldb::ProcessSP process_sp) : lldb_private::ABI(process_sp) {
104  // Call CreateInstance instead.
105  }
106 };
107 
108 #endif // liblldb_ABISysV_i386_h_
~ABISysV_i386() override=default
lldb_private::Status SetReturnValueObject(lldb::StackFrameSP &frame_sp, lldb::ValueObjectSP &new_value) override
lldb::ValueObjectSP GetReturnValueObjectImpl(lldb_private::Thread &thread, lldb_private::CompilerType &type) const override
static lldb_private::ConstString GetPluginNameStatic()
An architecture specification class.
Definition: ArchSpec.h:32
bool RegisterIsCalleeSaved(const lldb_private::RegisterInfo *reg_info)
bool CreateDefaultUnwindPlan(lldb_private::UnwindPlan &unwind_plan) override
bool CreateFunctionEntryUnwindPlan(lldb_private::UnwindPlan &unwind_plan) override
bool RegisterIsVolatile(const lldb_private::RegisterInfo *reg_info) override
Definition: ABISysV_i386.h:44
static lldb::ABISP CreateInstance(lldb::ProcessSP process_sp, const lldb_private::ArchSpec &arch)
bool PrepareTrivialCall(lldb_private::Thread &thread, lldb::addr_t sp, lldb::addr_t functionAddress, lldb::addr_t returnAddress, llvm::ArrayRef< lldb::addr_t > args) const override
#define UINT32_MAX
Definition: lldb-defines.h:31
static void Terminate()
const lldb_private::RegisterInfo * GetRegisterInfoArray(uint32_t &count) override
uint64_t addr_t
Definition: lldb-types.h:83
lldb_private::ConstString GetPluginName() override
A uniqued constant string class.
Definition: ConstString.h:38
static void Initialize()
lldb::ValueObjectSP GetReturnValueObjectSimple(lldb_private::Thread &thread, lldb_private::CompilerType &ast_type) const
bool GetArgumentValues(lldb_private::Thread &thread, lldb_private::ValueList &values) const override
bool CodeAddressIsValid(lldb::addr_t pc) override
Definition: ABISysV_i386.h:71
uint32_t GetPluginVersion() override
Definition: ABISysV_i386.h:93
bool CallFrameAddressIsValid(lldb::addr_t cfa) override
Definition: ABISysV_i386.h:62
size_t GetRedZoneSize() const override
Definition: ABISysV_i386.h:19
An error handling class.
Definition: Status.h:44