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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-exception6//7//===----------------------------------------------------------------------===//8 9#ifndef LLDB_SOURCE_PLUGINS_ABI_X86_ABIMACOSX_I386_H10#define LLDB_SOURCE_PLUGINS_ABI_X86_ABIMACOSX_I386_H11 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::Status30 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 userland41 // code, we've seen that the stack pointer is often not aligned properly42 // before the handler is invoked. This means that lldb will stop the unwind43 // early -- before the function which caused the trap.44 //45 // To work around this, we relax that alignment to be just word-size46 // (4-bytes).47 // Allowing the trap handlers for user space would be easy (_sigtramp) but48 // in other environments there can be a large number of different functions49 // involved in async traps.50 //51 // If we were to enforce 16-byte alignment, we also need to relax to 4-byte52 // 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 aligned55 if (cfa & (4ull - 1ull))56 return false; // Not 4 byte aligned57 if (cfa == 0)58 return false; // Zero is not a valid stack address59 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 Functions68 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 protocol76 77 static llvm::StringRef GetPluginNameStatic() { return "abi.macosx-i386"; }78 79 llvm::StringRef GetPluginName() override { return GetPluginNameStatic(); }80 81protected:82 lldb::ValueObjectSP83 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(name, "stmm", "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_H98