class Armv8AException(gdb.Command):
    def __init__ (self):
        super (Armv8AException, self).__init__ ("armv8a-exception", gdb.COMMAND_USER)
    
    def print_data_abort(self, frame, iss):
        isv = (iss >> 23) & 0x1
        sas = (iss >> 21) & 0x3
        sse = (iss >> 20) & 0x1
        srt = (iss >> 15) & 0x1f
        sf = (iss >> 14) & 0x1
        ar = (iss >> 13) & 0x1
        vncr = (iss >> 12) & 0x1
        _set = (iss >> 10) & 0x3
        fnv = (iss >> 9) & 0x1
        ea = (iss >> 8) & 0x1
        cm = (iss >> 7) & 0x1
        s1ptw = (iss >> 6) & 0x1
        wnr = (iss >> 5) & 0x1
        dfsc = iss & 0x1f
        if isv:
            # print("isv valid", sas, sse, srt, sf, ar)
            access_sizes = ("Byte", "Halfword", "Word", "Doubleword")
            print("Access size:", access_sizes[sas])
            print("Sign extended:", "Yes" if sse else "No")
            print("Register:", hex(srt), "64-bit" if sf else "32-bit")
            print("Acquire/Release:", "Yes" if ar else "No")
        if dfsc == 0b010000:
            print("Not on translation table walk")
            if not fnv:
                value = int(frame.read_register("FAR_EL2"))
                print("FAR", hex(value))
        elif dfsc == 0b000101:
            print("translation fault level 1")
        elif dfsc == 0b010001:
            print("tag check fault")
        elif dfsc == 0b100001:
            print("alignment fault")
        else:
            print(bin(dfsc))
        print(vncr, _set, fnv, ea, cm, s1ptw, wnr, dfsc)

    def print_instruction_abort(self, frame, iss):
        _set = (iss >> 10) & 0x3
        fnv = (iss >> 9) & 0x1
        ea = (iss >> 8) & 0x1
        s1ptw = (iss >> 6) & 0x1
        ifsc = iss & 0x1f
        if ifsc == 0b010000:
            print("Not on translation table walk")
            if not fnv:
                value = int(frame.read_register("FAR_EL2"))
                print("FAR", hex(value))
        elif ifsc == 0b00101:
            print("translation fault level 1")
        elif ifsc == 0b01001:
            print("access flag fault level 1")
        # elif dfsc == 0b100001:
        #     print("alignment fault")
        else:
            print(bin(ifsc))

    def invoke (self, arg, from_tty):
        frame = gdb.selected_frame()
        value = int(frame.read_register("ESR_EL2"))
        if value == 0:
            return None
        iss2 = (value >> 32) & 0x1ff
        ec = (value >> 26) & 0x3ff
        il = (value >> 25) & 0x1
        iss = value & 0xffffff
        if ec == 0b000000:
            print("Unknown fault")
        elif ec == 0b000001:
            print("Trapped WF*")
        elif ec == 0b000011:
            print("Trapped MCR or MRC")
        elif ec == 0b000100:
            print("Trapped MCRR or MRRC")
        elif ec == 0b000101:
            print("Trapped MCR or MRC")
        elif ec == 0b000110:
            print("Trapped LDC or STC")
        elif ec == 0b000111:
            print("Trapped SIMD")
        elif ec == 0b001000:
            print("Trapped VMRS")
        elif ec == 0b001001:
            print("Trapped pointer authentication")
        elif ec == 0b001010:
            print("Trapped LD64B or ST64B*")
        elif ec == 0b001100:
            print("Trapped MRRC")
        elif ec == 0b001101:
            print("Branch target exception")
        elif ec == 0b001110:
            print("Illegal execution state")
        elif ec == 0b010001:
            print("SVC instruction")
        elif ec == 0b010010:
            print("HVC instruction")
        elif ec == 0b010011:
            print("SMC instruction")
        elif ec == 0b010101:
            print("SVC instruction")
        elif ec == 0b010110:
            print("HVC instruction")
        elif ec == 0b010111:
            print("SMC instruction")
        elif ec == 0b011000:
            print("Trapped MRS, MRS or system instruction")
        elif ec == 0b011001:
            print("Trapped SVE")
        elif ec == 0b011010:
            print("Trapped ERET")
        elif ec == 0b011100:
            print("Failed pointer authentication")
        elif ec == 0b100000:
            print("Instruction abort from lower level")
        elif ec == 0b100001:
            print("Instruction abort from same level")
            self.print_instruction_abort(frame, iss)
        elif ec == 0b100010:
            print("PC alignment failure")
        elif ec == 0b100100:
            print("Data abort from lower level")
        elif ec == 0b100101:
            print("Data abort from same level")
            self.print_data_abort(frame, iss)
        elif ec == 0b100110:
            print("SP alignment fault")
        elif ec == 0b101000:
            print("32-bit floating point exception")
        elif ec == 0b101100:
            print("64-bit floating point exception")
        elif ec == 0b101111:
            print("SError interrupt")
        elif ec == 0b110000:
            print("Breakpoint from lower level")
        elif ec == 0b110001:
            print("Breakpoint from same level")
        elif ec == 0b110010:
            print("Software step from lower level")
        elif ec == 0b110011:
            print("Software step from same level")
        elif ec == 0b110100:
            print ("Watch point from same level")
        elif ec == 0b110101:
            print("Watch point from lower level")
        elif ec == 0b111000:
            print("Breakpoint in aarch32 mode")
        elif ec == 0b111010:
            print("Vector catch in aarch32")
        elif ec == 0b111100:
            print("Brk instruction in aarch64")
        print(hex(int(value)), iss2, bin(ec), il, iss)

Armv8AException()