LLDB  mainline
ABISysV_i386.h
Go to the documentation of this file.
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 LLDB_SOURCE_PLUGINS_ABI_X86_ABISYSV_I386_H
10 #define LLDB_SOURCE_PLUGINS_ABI_X86_ABISYSV_I386_H
11 
12 #include "Plugins/ABI/X86/ABIX86.h"
13 #include "lldb/lldb-private.h"
14 
15 class ABISysV_i386 : public ABIX86 {
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  // Static Functions
77 
78  static void Initialize();
79 
80  static void Terminate();
81 
82  static lldb::ABISP CreateInstance(lldb::ProcessSP process_sp, const lldb_private::ArchSpec &arch);
83 
84  // PluginInterface protocol
85 
87 
89 
90  uint32_t GetPluginVersion() override { return 1; }
91 
92 protected:
93  lldb::ValueObjectSP
95  lldb_private::CompilerType &ast_type) const;
96 
97  bool RegisterIsCalleeSaved(const lldb_private::RegisterInfo *reg_info);
98 
99 private:
100  using ABIX86::ABIX86; // Call CreateInstance instead.
101 };
102 
103 #endif // LLDB_SOURCE_PLUGINS_ABI_X86_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:33
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
Definition: ABIX86.h:14
static void Terminate()
uint64_t addr_t
Definition: lldb-types.h:83
lldb_private::ConstString GetPluginName() override
A uniqued constant string class.
Definition: ConstString.h:40
Represents a generic type in a programming language.
Definition: CompilerType.h:33
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:90
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