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 LLDB_SOURCE_PLUGINS_ABI_X86_ABIMACOSX_I386_H
10#define LLDB_SOURCE_PLUGINS_ABI_X86_ABIMACOSX_I386_H
11
12#include "Plugins/ABI/X86/ABIX86_i386.h"
13#include "lldb/Core/Value.h"
14#include "lldb/lldb-private.h"
15
16class ABIMacOSX_i386 : public ABIX86_i386 {
17public:
18 ~ABIMacOSX_i386() override = default;
19
20 size_t GetRedZoneSize() const override;
21
22 bool PrepareTrivialCall(lldb_private::Thread &thread, lldb::addr_t sp,
23 lldb::addr_t func_addr, lldb::addr_t return_addr,
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::UnwindPlanSP CreateFunctionEntryUnwindPlan() override;
34
35 lldb::UnwindPlanSP CreateDefaultUnwindPlan() override;
36
37 bool RegisterIsVolatile(const lldb_private::RegisterInfo *reg_info) override;
38
39 // The Darwin i386 ABI requires that stack frames be 16 byte aligned.
40 // When there is a trap handler on the stack, e.g. _sigtramp in userland
41 // code, we've seen that the stack pointer is often not aligned properly
42 // before the handler is invoked. This means that lldb will stop the unwind
43 // early -- before the function which caused the trap.
44 //
45 // To work around this, we relax that alignment to be just word-size
46 // (4-bytes).
47 // Allowing the trap handlers for user space would be easy (_sigtramp) but
48 // in other environments there can be a large number of different functions
49 // involved in async traps.
50 //
51 // If we were to enforce 16-byte alignment, we also need to relax to 4-byte
52 // alignment for non-darwin i386 targets.
53 bool CallFrameAddressIsValid(lldb::addr_t cfa) override {
54 // Make sure the stack call frame addresses are 4 byte aligned
55 if (cfa & (4ull - 1ull))
56 return false; // Not 4 byte aligned
57 if (cfa == 0)
58 return false; // Zero is not a valid stack address
59 return true;
60 }
61
62 bool CodeAddressIsValid(lldb::addr_t pc) override {
63 // Just make sure the address is a valid 32 bit address.
64 return pc <= UINT32_MAX;
65 }
66
67 // Static Functions
68
69 static void Initialize();
70
71 static void Terminate();
72
73 static lldb::ABISP CreateInstance(lldb::ProcessSP process_sp, const lldb_private::ArchSpec &arch);
74
75 // PluginInterface protocol
76
77 static llvm::StringRef GetPluginNameStatic() { return "abi.macosx-i386"; }
78
79 llvm::StringRef GetPluginName() override { return GetPluginNameStatic(); }
80
81protected:
82 lldb::ValueObjectSP
83 GetReturnValueObjectImpl(lldb_private::Thread &thread,
84 lldb_private::CompilerType &ast_type) const override;
85
86 bool RegisterIsCalleeSaved(const lldb_private::RegisterInfo *reg_info);
87
88 std::string GetMCName(std::string name) override {
89 MapRegisterName(reg&: name, from_prefix: "stmm", to_prefix: "st");
90 return name;
91 }
92
93private:
94 using ABIX86_i386::ABIX86_i386; // Call CreateInstance instead.
95};
96
97#endif // LLDB_SOURCE_PLUGINS_ABI_X86_ABIMACOSX_I386_H
98

source code of lldb/source/Plugins/ABI/X86/ABIMacOSX_i386.h