1 //===-- ABISysV_x86_64.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_X86_64_H 10 #define LLDB_SOURCE_PLUGINS_ABI_X86_ABISYSV_X86_64_H 11 12 #include "Plugins/ABI/X86/ABIX86_64.h" 13 14 class ABISysV_x86_64 : public ABIX86_64 { 15 public: 16 ~ABISysV_x86_64() override = default; 17 18 size_t GetRedZoneSize() const override; 19 20 bool PrepareTrivialCall(lldb_private::Thread &thread, lldb::addr_t sp, 21 lldb::addr_t functionAddress, 22 lldb::addr_t returnAddress, 23 llvm::ArrayRef<lldb::addr_t> args) const override; 24 25 bool GetArgumentValues(lldb_private::Thread &thread, 26 lldb_private::ValueList &values) const override; 27 28 lldb_private::Status 29 SetReturnValueObject(lldb::StackFrameSP &frame_sp, 30 lldb::ValueObjectSP &new_value) override; 31 32 lldb::ValueObjectSP 33 GetReturnValueObjectImpl(lldb_private::Thread &thread, 34 lldb_private::CompilerType &type) const override; 35 36 bool 37 CreateFunctionEntryUnwindPlan(lldb_private::UnwindPlan &unwind_plan) override; 38 39 bool CreateDefaultUnwindPlan(lldb_private::UnwindPlan &unwind_plan) override; 40 41 bool RegisterIsVolatile(const lldb_private::RegisterInfo *reg_info) override; 42 43 // The SysV x86_64 ABI requires that stack frames be 16 byte aligned. 44 // When there is a trap handler on the stack, e.g. _sigtramp in userland 45 // code, we've seen that the stack pointer is often not aligned properly 46 // before the handler is invoked. This means that lldb will stop the unwind 47 // early -- before the function which caused the trap. 48 // 49 // To work around this, we relax that alignment to be just word-size 50 // (8-bytes). 51 // Allowing the trap handlers for user space would be easy (_sigtramp) but 52 // in other environments there can be a large number of different functions 53 // involved in async traps. CallFrameAddressIsValid(lldb::addr_t cfa)54 bool CallFrameAddressIsValid(lldb::addr_t cfa) override { 55 // Make sure the stack call frame addresses are 8 byte aligned 56 if (cfa & (8ull - 1ull)) 57 return false; // Not 8 byte aligned 58 if (cfa == 0) 59 return false; // Zero is not a valid stack address 60 return true; 61 } 62 CodeAddressIsValid(lldb::addr_t pc)63 bool CodeAddressIsValid(lldb::addr_t pc) override { 64 // We have a 64 bit address space, so anything is valid as opcodes 65 // aren't fixed width... 66 return true; 67 } 68 69 bool GetPointerReturnRegister(const char *&name) override; 70 71 // Static Functions 72 73 static void Initialize(); 74 75 static void Terminate(); 76 77 static lldb::ABISP CreateInstance(lldb::ProcessSP process_sp, const lldb_private::ArchSpec &arch); 78 79 static lldb_private::ConstString GetPluginNameStatic(); 80 81 // PluginInterface protocol 82 83 lldb_private::ConstString GetPluginName() override; 84 85 uint32_t GetPluginVersion() override; 86 87 protected: 88 void CreateRegisterMapIfNeeded(); 89 90 lldb::ValueObjectSP 91 GetReturnValueObjectSimple(lldb_private::Thread &thread, 92 lldb_private::CompilerType &ast_type) const; 93 94 bool RegisterIsCalleeSaved(const lldb_private::RegisterInfo *reg_info); 95 uint32_t GetGenericNum(llvm::StringRef reg) override; 96 97 private: 98 using ABIX86_64::ABIX86_64; // Call CreateInstance instead. 99 }; 100 101 #endif // LLDB_SOURCE_PLUGINS_ABI_X86_ABISYSV_X86_64_H 102