1 //===-- RegisterFlagsLinux_arm64.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_PROCESS_UTILITY_REGISTERFLAGSLINUX_ARM64_H 10 #define LLDB_SOURCE_PLUGINS_PROCESS_UTILITY_REGISTERFLAGSLINUX_ARM64_H 11 12 #include "lldb/Target/RegisterFlags.h" 13 #include "llvm/ADT/StringRef.h" 14 #include <functional> 15 16 namespace lldb_private { 17 18 struct RegisterInfo; 19 20 /// This class manages the storage and detection of register field information 21 /// for Arm64 Linux registers. The same register may have different fields on 22 /// different CPUs. This class abstracts out the field detection process so we 23 /// can use it on live processes and core files. 24 /// 25 /// The general way to use this class is: 26 /// * Make an instance somewhere that will last as long as the debug session 27 /// (because your final register info will point to this instance). 28 /// * Read hardware capabilities from a core note, binary, prctl, etc. 29 /// * Pass those to DetectFields. 30 /// * Call UpdateRegisterInfo with your RegisterInfo to add pointers 31 /// to the detected fields for all registers listed in this class. 32 /// 33 /// This must be done in that order, and you should ensure that if multiple 34 /// threads will reference the information, a mutex is used to make sure only 35 /// one calls DetectFields. 36 class LinuxArm64RegisterFlags { 37 public: 38 /// For the registers listed in this class, detect which fields are 39 /// present. Must be called before UpdateRegisterInfos. 40 /// If called more than once, fields will be redetected each time from 41 /// scratch. If you do not have access to hwcap, just pass 0 for each one, you 42 /// will only get unconditional fields. 43 void DetectFields(uint64_t hwcap, uint64_t hwcap2); 44 45 /// Add the field information of any registers named in this class, 46 /// to the relevant RegisterInfo instances. Note that this will be done 47 /// with a pointer to the instance of this class that you call this on, so 48 /// the lifetime of that instance must be at least that of the register info. 49 void UpdateRegisterInfo(const RegisterInfo *reg_info, uint32_t num_regs); 50 51 /// Returns true if field detection has been run at least once. 52 bool HasDetected() const { return m_has_detected; } 53 54 private: 55 using Fields = std::vector<RegisterFlags::Field>; 56 using DetectorFn = std::function<Fields(uint64_t, uint64_t)>; 57 58 static Fields DetectCPSRFields(uint64_t hwcap, uint64_t hwcap2); 59 static Fields DetectFPSRFields(uint64_t hwcap, uint64_t hwcap2); 60 static Fields DetectFPCRFields(uint64_t hwcap, uint64_t hwcap2); 61 static Fields DetectMTECtrlFields(uint64_t hwcap, uint64_t hwcap2); 62 static Fields DetectSVCRFields(uint64_t hwcap, uint64_t hwcap2); 63 64 struct RegisterEntry { 65 RegisterEntry(llvm::StringRef name, unsigned size, DetectorFn detector) 66 : m_name(name), m_flags(std::string(name) + "_flags", size, {{"", 0}}), 67 m_detector(detector) {} 68 69 llvm::StringRef m_name; 70 RegisterFlags m_flags; 71 DetectorFn m_detector; 72 } m_registers[5] = { 73 RegisterEntry("cpsr", 4, DetectCPSRFields), 74 RegisterEntry("fpsr", 4, DetectFPSRFields), 75 RegisterEntry("fpcr", 4, DetectFPCRFields), 76 RegisterEntry("mte_ctrl", 8, DetectMTECtrlFields), 77 RegisterEntry("svcr", 8, DetectSVCRFields), 78 }; 79 80 // Becomes true once field detection has been run for all registers. 81 bool m_has_detected = false; 82 }; 83 84 } // namespace lldb_private 85 86 #endif // LLDB_SOURCE_PLUGINS_PROCESS_UTILITY_REGISTERFLAGSLINUX_ARM64_H