================ @@ -0,0 +1,486 @@ +""" +Specification, compiler, disassembler, and interpreter +for LLDB dataformatter bytecode. + +See formatter-bytecode.md for more details. +""" +from __future__ import annotations + +# Types +type_String = 1 +type_Int = 2 +type_UInt = 3 +type_Object = 4 +type_Type = 5 + +# Opcodes +opcode = dict() + + +def define_opcode(n, mnemonic, name): + globals()["op_" + name] = n + if mnemonic: + opcode[mnemonic] = n + opcode[n] = mnemonic + + +define_opcode(1, "dup", "dup") +define_opcode(2, "drop", "drop") +define_opcode(3, "pick", "pick") +define_opcode(4, "over", "over") +define_opcode(5, "swap", "swap") +define_opcode(6, "rot", "rot") + +define_opcode(0x10, "{", "begin") +define_opcode(0x11, "if", "if") +define_opcode(0x12, "ifelse", "ifelse") + +define_opcode(0x20, None, "lit_uint") +define_opcode(0x21, None, "lit_int") +define_opcode(0x22, None, "lit_string") +define_opcode(0x23, None, "lit_selector") + +define_opcode(0x30, "+", "plus") +define_opcode(0x31, "-", "minus") +define_opcode(0x32, "*", "mul") +define_opcode(0x33, "/", "div") +define_opcode(0x34, "%", "mod") +define_opcode(0x35, "<<", "shl") +define_opcode(0x36, ">>", "shr") +define_opcode(0x37, "shra", "shra") + +define_opcode(0x40, "&", "and") +define_opcode(0x41, "|", "or") +define_opcode(0x42, "^", "xor") +define_opcode(0x43, "~", "not") + +define_opcode(0x50, "=", "eq") +define_opcode(0x51, "!=", "neq") +define_opcode(0x52, "<", "lt") +define_opcode(0x53, ">", "gt") +define_opcode(0x54, "=<", "le") +define_opcode(0x55, ">=", "ge") + +define_opcode(0x60, "call", "call") + +# Function signatures +sig_summary = 0 +sig_init = 1 +sig_get_num_children = 2 +sig_get_child_index = 3 +sig_get_child_at_index = 4 + +# Selectors +selector = dict() + + +def define_selector(n, name): + globals()["sel_" + name] = n + selector["@" + name] = n + selector[n] = "@" + name + + +define_selector(0, "summary") +define_selector(1, "type_summary") + +define_selector(0x10, "get_num_children") +define_selector(0x11, "get_child_at_index") +define_selector(0x12, "get_child_with_name") +define_selector(0x13, "get_child_index") +define_selector(0x15, "get_type") +define_selector(0x16, "get_template_argument_type") +define_selector(0x20, "get_value") +define_selector(0x21, "get_value_as_unsigned") +define_selector(0x22, "get_value_as_signed") +define_selector(0x23, "get_value_as_address") +define_selector(0x24, "cast") + +define_selector(0x40, "read_memory_byte") +define_selector(0x41, "read_memory_uint32") +define_selector(0x42, "read_memory_int32") +define_selector(0x43, "read_memory_unsigned") +define_selector(0x44, "read_memory_signed") +define_selector(0x45, "read_memory_address") +define_selector(0x46, "read_memory") + +define_selector(0x50, "fmt") +define_selector(0x51, "sprintf") +define_selector(0x52, "strlen") + + +################################################################################ +# Compiler. +################################################################################ + + +def compile(assembler: str) -> bytearray: + """Compile assembler into bytecode""" + # This is a stack of all in-flight/unterminated blocks. + bytecode = [bytearray()] + + def emit(byte): + bytecode[-1].append(byte) + + tokens = list(assembler.split(" ")) + tokens.reverse() + while tokens: + tok = tokens.pop() + if tok == "": + pass + elif tok == "{": + bytecode.append(bytearray()) + elif tok == "}": + block = bytecode.pop() + emit(op_begin) + emit(len(block)) # FIXME: uleb + bytecode[-1].extend(block) + elif tok[0].isdigit(): + if tok[-1] == "u": + emit(op_lit_uint) + emit(int(tok[:-1])) # FIXME + else: + emit(op_lit_int) + emit(int(tok)) # FIXME + elif tok[0] == "@": + emit(op_lit_selector) + emit(selector[tok]) + elif tok[0] == '"': + s = bytearray() + done = False + chrs = tok[1:] + while not done: + quoted = False + for c in chrs: + if quoted: + s.append(ord(c)) # FIXME + quoted = False + elif c == "\\": + quoted = True + elif c == '"': + done = True + break + # FIXME assert this is last in token + else: + s.append(ord(c)) + if not done: + s.append(ord(" ")) + chrs = tokens.pop() + + emit(op_lit_string) + emit(len(s)) + bytecode[-1].extend(s) + else: + emit(opcode[tok]) + assert len(bytecode) == 1 # unterminated { + return bytecode[0] + + +################################################################################ +# Disassembler. +################################################################################ + + +def disassemble(bytecode: bytearray) -> (str, int): + """Disassemble bytecode into (assembler, token starts)""" + asm = "" + all_bytes = list(bytecode) + all_bytes.reverse() + blocks = [] + tokens = [0] + + def next_byte(): + """Fetch the next byte in the bytecode and keep track of all + in-flight blocks""" + for i in range(len(blocks)): + blocks[i] -= 1 + tokens.append(len(asm)) + return all_bytes.pop() + + while all_bytes: + b = next_byte() + if b == op_begin: + asm += "{" + length = next_byte() + blocks.append(length) + elif b == op_lit_uint: + b = next_byte() + asm += str(b) # FIXME uleb + asm += "u" + elif b == op_lit_int: + b = next_byte() + asm += str(b) + elif b == op_lit_selector: + b = next_byte() + asm += selector[b] + elif b == op_lit_string: + length = next_byte() + s = "'" + while length: + s += chr(next_byte()) + length -= 1 + asm += '"' + repr(s)[2:] + else: + asm += opcode[b] + + while blocks and blocks[-1] == 0: + asm += " }" + blocks.pop() + + if all_bytes: + asm += " " + + if blocks: + asm += "ERROR" + return asm, tokens + + +################################################################################ +# Interpreter. +################################################################################ + + +def count_fmt_params(fmt: str) -> int: + """Count the number of parameters in a format string""" + from string import Formatter + + f = Formatter() + n = 0 + for _, name, _, _ in f.parse(fmt): ---------------- DavidSpickett wrote:
I didn't know you could parse a format string like this, very cool. https://github.com/llvm/llvm-project/pull/113398 _______________________________________________ lldb-commits mailing list lldb-commits@lists.llvm.org https://lists.llvm.org/cgi-bin/mailman/listinfo/lldb-commits