1 //===-- ABIMacOSX_i386.h ----------------------------------------*- C++ -*-===//
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
7 //===----------------------------------------------------------------------===//
9 #ifndef liblldb_ABIMacOSX_i386_h_
10 #define liblldb_ABIMacOSX_i386_h_
12 #include "lldb/Core/Value.h"
13 #include "lldb/Target/ABI.h"
14 #include "lldb/lldb-private.h"
16 class ABIMacOSX_i386 : public lldb_private::ABI {
18 ~ABIMacOSX_i386() override = default;
20 size_t GetRedZoneSize() const override;
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;
26 bool GetArgumentValues(lldb_private::Thread &thread,
27 lldb_private::ValueList &values) const override;
30 SetReturnValueObject(lldb::StackFrameSP &frame_sp,
31 lldb::ValueObjectSP &new_value) override;
34 CreateFunctionEntryUnwindPlan(lldb_private::UnwindPlan &unwind_plan) override;
36 bool CreateDefaultUnwindPlan(lldb_private::UnwindPlan &unwind_plan) override;
38 bool RegisterIsVolatile(const lldb_private::RegisterInfo *reg_info) override;
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.
46 // To work around this, we relax that alignment to be just word-size
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.
52 // If we were to enforce 16-byte alignment, we also need to relax to 4-byte
53 // alignment for non-darwin i386 targets.
54 bool CallFrameAddressIsValid(lldb::addr_t cfa) override {
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
59 return false; // Zero is not a valid stack address
63 bool CodeAddressIsValid(lldb::addr_t pc) override {
64 // Just make sure the address is a valid 32 bit address.
65 return pc <= UINT32_MAX;
68 const lldb_private::RegisterInfo *
69 GetRegisterInfoArray(uint32_t &count) override;
73 static void Initialize();
75 static void Terminate();
77 static lldb::ABISP CreateInstance(lldb::ProcessSP process_sp, const lldb_private::ArchSpec &arch);
79 // PluginInterface protocol
81 static lldb_private::ConstString GetPluginNameStatic();
83 lldb_private::ConstString GetPluginName() override;
85 uint32_t GetPluginVersion() override;
89 GetReturnValueObjectImpl(lldb_private::Thread &thread,
90 lldb_private::CompilerType &ast_type) const override;
92 bool RegisterIsCalleeSaved(const lldb_private::RegisterInfo *reg_info);
95 ABIMacOSX_i386(lldb::ProcessSP process_sp) : lldb_private::ABI(process_sp) {
96 // Call CreateInstance instead.
100 #endif // liblldb_ABIMacOSX_i386_h_