-- Adapted from the amazing Yueliang project -- http://yueliang.luaforge.net/ --[[-------------------------------------------------------------------- luac.lua Primitive luac in Lua This file is part of Yueliang. Copyright (c) 2005-2007 Kein-Hong Man The COPYRIGHT file describes the conditions under which this software may be distributed. See the ChangeLog for more information. ----------------------------------------------------------------------]] --[[-------------------------------------------------------------------- -- Notes: -- * based on luac.lua in the test directory of the 5.1.2 distribution -- * usage: lua luac.lua file.lua ----------------------------------------------------------------------]] ------------------------------------------------------------------------ -- load and initialize the required modules ------------------------------------------------------------------------ do local luaZ = {} local luaY = {} local luaX = {} local luaP = {} local luaU = {} local luaK = {} local size_size_t = 8 -- currently asserts are enabled because the codebase hasn't been tested -- much (if you don't want asserts, just comment them out) local function lua_assert(test) if not test then error("assertion failed!") end end -- dofile("lzio.lua") ------------------------------------------------------------------------ -- * reader() should return a string, or nil if nothing else to parse. -- Additional data can be set only during stream initialization -- * Readers are handled in lauxlib.c, see luaL_load(file|buffer|string) -- * LUAL_BUFFERSIZE=BUFSIZ=512 in make_getF() (located in luaconf.h) -- * Original Reader typedef: -- const char * (*lua_Reader) (lua_State *L, void *ud, size_t *sz); -- * This Lua chunk reader implementation: -- returns string or nil, no arguments to function ------------------------------------------------------------------------ ------------------------------------------------------------------------ -- create a chunk reader from a source string ------------------------------------------------------------------------ function luaZ:make_getS(buff) local b = buff return function() -- chunk reader anonymous function here if not b then return nil end local data = b b = nil return data end end ------------------------------------------------------------------------ -- create a chunk reader from a source file ------------------------------------------------------------------------ -- function luaZ:make_getF(filename) -- local LUAL_BUFFERSIZE = 512 -- local h = io.open(filename, "r") -- if not h then return nil end -- return function() -- chunk reader anonymous function here -- if not h or io.type(h) == "closed file" then return nil end -- local buff = h:read(LUAL_BUFFERSIZE) -- if not buff then h:close(); h = nil end -- return buff -- end -- end function luaZ:make_getF(source) local LUAL_BUFFERSIZE = 512 local pos = 1 return function() -- chunk reader anonymous function here local buff = source:sub(pos, pos + LUAL_BUFFERSIZE - 1) pos = math.min(#source + 1, pos + LUAL_BUFFERSIZE) return buff end end ------------------------------------------------------------------------ -- creates a zio input stream -- returns the ZIO structure, z ------------------------------------------------------------------------ function luaZ:init(reader, data) if not reader then return end local z = {} z.reader = reader z.data = data or "" z.name = name -- set up additional data for reading if not data or data == "" then z.n = 0 else z.n = #data end z.p = 0 return z end ------------------------------------------------------------------------ -- fill up input buffer ------------------------------------------------------------------------ function luaZ:fill(z) local buff = z.reader() z.data = buff if not buff or buff == "" then return "EOZ" end z.n, z.p = #buff - 1, 1 return string.sub(buff, 1, 1) end ------------------------------------------------------------------------ -- get next character from the input stream -- * local n, p are used to optimize code generation ------------------------------------------------------------------------ function luaZ:zgetc(z) local n, p = z.n, z.p + 1 if n > 0 then z.n, z.p = n - 1, p return string.sub(z.data, p, p) else return self:fill(z) end end -- dofile("llex.lua") -- FIRST_RESERVED is not required as tokens are manipulated as strings -- TOKEN_LEN deleted; maximum length of a reserved word not needed ------------------------------------------------------------------------ -- "ORDER RESERVED" deleted; enumeration in one place: luaX.RESERVED ------------------------------------------------------------------------ -- terminal symbols denoted by reserved words: TK_AND to TK_WHILE -- other terminal symbols: TK_NAME to TK_EOS luaX.RESERVED = [[ TK_AND and TK_BREAK break TK_DO do TK_ELSE else TK_ELSEIF elseif TK_END end TK_FALSE false TK_FOR for TK_FUNCTION function TK_IF if TK_IN in TK_LOCAL local TK_NIL nil TK_NOT not TK_OR or TK_REPEAT repeat TK_RETURN return TK_THEN then TK_TRUE true TK_UNTIL until TK_WHILE while TK_CONCAT .. TK_DOTS ... TK_EQ == TK_GE >= TK_LE <= TK_NE ~= TK_NAME TK_NUMBER TK_STRING TK_EOS ]] -- NUM_RESERVED is not required; number of reserved words --[[-------------------------------------------------------------------- -- Instead of passing seminfo, the Token struct (e.g. ls.t) is passed -- so that lexer functions can use its table element, ls.t.seminfo -- -- SemInfo (struct no longer needed, a mixed-type value is used) -- -- Token (struct of ls.t and ls.lookahead): -- token -- token symbol -- seminfo -- semantics information -- -- LexState (struct of ls; ls is initialized by luaX:setinput): -- current -- current character (charint) -- linenumber -- input line counter -- lastline -- line of last token 'consumed' -- t -- current token (table: struct Token) -- lookahead -- look ahead token (table: struct Token) -- fs -- 'FuncState' is private to the parser -- L -- LuaState -- z -- input stream -- buff -- buffer for tokens -- source -- current source name -- decpoint -- locale decimal point -- nestlevel -- level of nested non-terminals ----------------------------------------------------------------------]] -- luaX.tokens (was luaX_tokens) is now a hash; see luaX:init luaX.MAXSRC = 80 luaX.MAX_INT = 2147483645 -- constants from elsewhere (see above) luaX.LUA_QS = "'%s'" luaX.LUA_COMPAT_LSTR = 1 --luaX.MAX_SIZET = 4294967293 ------------------------------------------------------------------------ -- initialize lexer -- * original luaX_init has code to create and register token strings -- * luaX.tokens: TK_* -> token -- * luaX.enums: token -> TK_* (used in luaX:llex) ------------------------------------------------------------------------ function luaX:init() local tokens, enums = {}, {} for v in string.gmatch(self.RESERVED, "[^\n]+") do local _, _, tok, str = string.find(v, "(%S+)%s+(%S+)") tokens[tok] = str enums[str] = tok end self.tokens = tokens self.enums = enums end ------------------------------------------------------------------------ -- returns a suitably-formatted chunk name or id -- * from lobject.c, used in llex.c and ldebug.c -- * the result, out, is returned (was first argument) ------------------------------------------------------------------------ function luaX:chunkid(source, bufflen) local out local first = string.sub(source, 1, 1) if first == "=" then out = string.sub(source, 2, bufflen) -- remove first char else -- out = "source", or "...source" if first == "@" then source = string.sub(source, 2) -- skip the '@' bufflen = bufflen - #" '...' " local l = #source out = "" if l > bufflen then source = string.sub(source, 1 + l - bufflen) -- get last part of file name out = out.."..." end out = out..source else -- out = [string "string"] local len = string.find(source, "[\n\r]") -- stop at first newline len = len and (len - 1) or #source bufflen = bufflen - #(" [string \"...\"] ") if len > bufflen then len = bufflen end out = "[string \"" if len < #source then -- must truncate? out = out..string.sub(source, 1, len).."..." else out = out..source end out = out.."\"]" end end return out end --[[-------------------------------------------------------------------- -- Support functions for lexer -- * all lexer errors eventually reaches lexerror: syntaxerror -> lexerror ----------------------------------------------------------------------]] ------------------------------------------------------------------------ -- look up token and return keyword if found (also called by parser) ------------------------------------------------------------------------ function luaX:token2str(ls, token) if string.sub(token, 1, 3) ~= "TK_" then if string.find(token, "%c") then return string.format("char(%d)", string.byte(token)) end return token else return self.tokens[token] end end ------------------------------------------------------------------------ -- throws a lexer error -- * txtToken has been made local to luaX:lexerror -- * can't communicate LUA_ERRSYNTAX, so it is unimplemented ------------------------------------------------------------------------ function luaX:lexerror(ls, msg, token) local function txtToken(ls, token) if token == "TK_NAME" or token == "TK_STRING" or token == "TK_NUMBER" then return ls.buff else return self:token2str(ls, token) end end local buff = self:chunkid(ls.source, self.MAXSRC) local msg = string.format("%s:%d: %s", buff, ls.linenumber, msg) if token then msg = string.format("%s near "..self.LUA_QS, msg, txtToken(ls, token)) end -- luaD_throw(ls->L, LUA_ERRSYNTAX) error(msg) end ------------------------------------------------------------------------ -- throws a syntax error (mainly called by parser) -- * ls.t.token has to be set by the function calling luaX:llex -- (see luaX:next and luaX:lookahead elsewhere in this file) ------------------------------------------------------------------------ function luaX:syntaxerror(ls, msg) self:lexerror(ls, msg, ls.t.token) end ------------------------------------------------------------------------ -- move on to next line ------------------------------------------------------------------------ function luaX:currIsNewline(ls) return ls.current == "\n" or ls.current == "\r" end function luaX:inclinenumber(ls) local old = ls.current -- lua_assert(currIsNewline(ls)) self:nextc(ls) -- skip '\n' or '\r' if self:currIsNewline(ls) and ls.current ~= old then self:nextc(ls) -- skip '\n\r' or '\r\n' end ls.linenumber = ls.linenumber + 1 if ls.linenumber >= self.MAX_INT then self:syntaxerror(ls, "chunk has too many lines") end end ------------------------------------------------------------------------ -- initializes an input stream for lexing -- * if ls (the lexer state) is passed as a table, then it is filled in, -- otherwise it has to be retrieved as a return value -- * LUA_MINBUFFER not used; buffer handling not required any more ------------------------------------------------------------------------ function luaX:setinput(L, ls, z, source) if not ls then ls = {} end -- create struct if not ls.lookahead then ls.lookahead = {} end if not ls.t then ls.t = {} end ls.decpoint = "." ls.L = L ls.lookahead.token = "TK_EOS" -- no look-ahead token ls.z = z ls.fs = nil ls.linenumber = 1 ls.lastline = 1 ls.source = source self:nextc(ls) -- read first char end --[[-------------------------------------------------------------------- -- LEXICAL ANALYZER ----------------------------------------------------------------------]] ------------------------------------------------------------------------ -- checks if current character read is found in the set 'set' ------------------------------------------------------------------------ function luaX:check_next(ls, set) if not string.find(set, ls.current, 1, 1) then return false end self:save_and_next(ls) return true end ------------------------------------------------------------------------ -- retrieve next token, checking the lookahead buffer if necessary -- * note that the macro next(ls) in llex.c is now luaX:nextc -- * utilized used in lparser.c (various places) ------------------------------------------------------------------------ function luaX:next(ls) ls.lastline = ls.linenumber if ls.lookahead.token ~= "TK_EOS" then -- is there a look-ahead token? -- this must be copy-by-value ls.t.seminfo = ls.lookahead.seminfo -- use this one ls.t.token = ls.lookahead.token ls.lookahead.token = "TK_EOS" -- and discharge it else ls.t.token = self:llex(ls, ls.t) -- read next token end end ------------------------------------------------------------------------ -- fill in the lookahead buffer -- * utilized used in lparser.c:constructor ------------------------------------------------------------------------ function luaX:lookahead(ls) -- lua_assert(ls.lookahead.token == "TK_EOS") ls.lookahead.token = self:llex(ls, ls.lookahead) end ------------------------------------------------------------------------ -- gets the next character and returns it -- * this is the next() macro in llex.c; see notes at the beginning ------------------------------------------------------------------------ function luaX:nextc(ls) local c = luaZ:zgetc(ls.z) ls.current = c return c end ------------------------------------------------------------------------ -- saves the given character into the token buffer -- * buffer handling code removed, not used in this implementation -- * test for maximum token buffer length not used, makes things faster ------------------------------------------------------------------------ function luaX:save(ls, c) local buff = ls.buff -- if you want to use this, please uncomment luaX.MAX_SIZET further up --if #buff > self.MAX_SIZET then -- self:lexerror(ls, "lexical element too long") --end ls.buff = buff..c end ------------------------------------------------------------------------ -- save current character into token buffer, grabs next character -- * like luaX:nextc, returns the character read for convenience ------------------------------------------------------------------------ function luaX:save_and_next(ls) self:save(ls, ls.current) return self:nextc(ls) end ------------------------------------------------------------------------ -- LUA_NUMBER -- * luaX:read_numeral is the main lexer function to read a number -- * luaX:str2d, luaX:buffreplace, luaX:trydecpoint are support functions ------------------------------------------------------------------------ ------------------------------------------------------------------------ -- string to number converter (was luaO_str2d from lobject.c) -- * returns the number, nil if fails (originally returns a boolean) -- * conversion function originally lua_str2number(s,p), a macro which -- maps to the strtod() function by default (from luaconf.h) ------------------------------------------------------------------------ function luaX:str2d(s) local result = tonumber(s) if result then return result end -- conversion failed if string.lower(string.sub(s, 1, 2)) == "0x" then -- maybe an hexadecimal constant? result = tonumber(s, 16) if result then return result end -- most common case -- Was: invalid trailing characters? -- In C, this function then skips over trailing spaces. -- true is returned if nothing else is found except for spaces. -- If there is still something else, then it returns a false. -- All this is not necessary using Lua's tonumber. end return nil end ------------------------------------------------------------------------ -- single-character replacement, for locale-aware decimal points ------------------------------------------------------------------------ function luaX:buffreplace(ls, from, to) local result, buff = "", ls.buff for p = 1, #buff do local c = string.sub(buff, p, p) if c == from then c = to end result = result..c end ls.buff = result end ------------------------------------------------------------------------ -- Attempt to convert a number by translating '.' decimal points to -- the decimal point character used by the current locale. This is not -- needed in Yueliang as Lua's tonumber() is already locale-aware. -- Instead, the code is here in case the user implements localeconv(). ------------------------------------------------------------------------ function luaX:trydecpoint(ls, Token) -- format error: try to update decimal point separator local old = ls.decpoint -- translate the following to Lua if you implement localeconv(): -- struct lconv *cv = localeconv(); -- ls->decpoint = (cv ? cv->decimal_point[0] : '.'); self:buffreplace(ls, old, ls.decpoint) -- try updated decimal separator local seminfo = self:str2d(ls.buff) Token.seminfo = seminfo if not seminfo then -- format error with correct decimal point: no more options self:buffreplace(ls, ls.decpoint, ".") -- undo change (for error message) self:lexerror(ls, "malformed number", "TK_NUMBER") end end ------------------------------------------------------------------------ -- main number conversion function -- * "^%w$" needed in the scan in order to detect "EOZ" ------------------------------------------------------------------------ function luaX:read_numeral(ls, Token) -- lua_assert(string.find(ls.current, "%d")) repeat self:save_and_next(ls) until string.find(ls.current, "%D") and ls.current ~= "." if self:check_next(ls, "Ee") then -- 'E'? self:check_next(ls, "+-") -- optional exponent sign end while string.find(ls.current, "^%w$") or ls.current == "_" do self:save_and_next(ls) end self:buffreplace(ls, ".", ls.decpoint) -- follow locale for decimal point local seminfo = self:str2d(ls.buff) Token.seminfo = seminfo if not seminfo then -- format error? self:trydecpoint(ls, Token) -- try to update decimal point separator end end ------------------------------------------------------------------------ -- count separators ("=") in a long string delimiter -- * used by luaX:read_long_string ------------------------------------------------------------------------ function luaX:skip_sep(ls) local count = 0 local s = ls.current -- lua_assert(s == "[" or s == "]") self:save_and_next(ls) while ls.current == "=" do self:save_and_next(ls) count = count + 1 end return (ls.current == s) and count or (-count) - 1 end ------------------------------------------------------------------------ -- reads a long string or long comment ------------------------------------------------------------------------ function luaX:read_long_string(ls, Token, sep) local cont = 0 self:save_and_next(ls) -- skip 2nd '[' if self:currIsNewline(ls) then -- string starts with a newline? self:inclinenumber(ls) -- skip it end while true do local c = ls.current if c == "EOZ" then self:lexerror(ls, Token and "unfinished long string" or "unfinished long comment", "TK_EOS") elseif c == "[" then --# compatibility code start if self.LUA_COMPAT_LSTR then if self:skip_sep(ls) == sep then self:save_and_next(ls) -- skip 2nd '[' cont = cont + 1 --# compatibility code start if self.LUA_COMPAT_LSTR == 1 then if sep == 0 then self:lexerror(ls, "nesting of [[...]] is deprecated", "[") end end --# compatibility code end end end --# compatibility code end elseif c == "]" then if self:skip_sep(ls) == sep then self:save_and_next(ls) -- skip 2nd ']' --# compatibility code start if self.LUA_COMPAT_LSTR and self.LUA_COMPAT_LSTR == 2 then cont = cont - 1 if sep == 0 and cont >= 0 then break end end --# compatibility code end break end elseif self:currIsNewline(ls) then self:save(ls, "\n") self:inclinenumber(ls) if not Token then ls.buff = "" end -- avoid wasting space else -- default if Token then self:save_and_next(ls) else self:nextc(ls) end end--if c end--while if Token then local p = 3 + sep Token.seminfo = string.sub(ls.buff, p, -p) end end ------------------------------------------------------------------------ -- reads a string -- * has been restructured significantly compared to the original C code ------------------------------------------------------------------------ function luaX:read_string(ls, del, Token) self:save_and_next(ls) while ls.current ~= del do local c = ls.current if c == "EOZ" then self:lexerror(ls, "unfinished string", "TK_EOS") elseif self:currIsNewline(ls) then self:lexerror(ls, "unfinished string", "TK_STRING") elseif c == "\\" then c = self:nextc(ls) -- do not save the '\' if self:currIsNewline(ls) then -- go through self:save(ls, "\n") self:inclinenumber(ls) elseif c ~= "EOZ" then -- will raise an error next loop -- escapes handling greatly simplified here: local i = string.find("abfnrtv", c, 1, 1) if i then self:save(ls, string.sub("\a\b\f\n\r\t\v", i, i)) self:nextc(ls) elseif not string.find(c, "%d") then self:save_and_next(ls) -- handles \\, \", \', and \? else -- \xxx c, i = 0, 0 repeat c = 10 * c + ls.current self:nextc(ls) i = i + 1 until i >= 3 or not string.find(ls.current, "%d") if c > 255 then -- UCHAR_MAX self:lexerror(ls, "escape sequence too large", "TK_STRING") end self:save(ls, string.char(c)) end end else self:save_and_next(ls) end--if c end--while self:save_and_next(ls) -- skip delimiter Token.seminfo = string.sub(ls.buff, 2, -2) end ------------------------------------------------------------------------ -- main lexer function ------------------------------------------------------------------------ function luaX:llex(ls, Token) ls.buff = "" while true do local c = ls.current ---------------------------------------------------------------- if self:currIsNewline(ls) then self:inclinenumber(ls) ---------------------------------------------------------------- elseif c == "-" then c = self:nextc(ls) if c ~= "-" then return "-" end -- else is a comment local sep = -1 if self:nextc(ls) == '[' then sep = self:skip_sep(ls) ls.buff = "" -- 'skip_sep' may dirty the buffer end if sep >= 0 then self:read_long_string(ls, nil, sep) -- long comment ls.buff = "" else -- else short comment while not self:currIsNewline(ls) and ls.current ~= "EOZ" do self:nextc(ls) end end ---------------------------------------------------------------- elseif c == "[" then local sep = self:skip_sep(ls) if sep >= 0 then self:read_long_string(ls, Token, sep) return "TK_STRING" elseif sep == -1 then return "[" else self:lexerror(ls, "invalid long string delimiter", "TK_STRING") end ---------------------------------------------------------------- elseif c == "=" then c = self:nextc(ls) if c ~= "=" then return "=" else self:nextc(ls); return "TK_EQ" end ---------------------------------------------------------------- elseif c == "<" then c = self:nextc(ls) if c ~= "=" then return "<" else self:nextc(ls); return "TK_LE" end ---------------------------------------------------------------- elseif c == ">" then c = self:nextc(ls) if c ~= "=" then return ">" else self:nextc(ls); return "TK_GE" end ---------------------------------------------------------------- elseif c == "~" then c = self:nextc(ls) if c ~= "=" then return "~" else self:nextc(ls); return "TK_NE" end ---------------------------------------------------------------- elseif c == "\"" or c == "'" then self:read_string(ls, c, Token) return "TK_STRING" ---------------------------------------------------------------- elseif c == "." then c = self:save_and_next(ls) if self:check_next(ls, ".") then if self:check_next(ls, ".") then return "TK_DOTS" -- ... else return "TK_CONCAT" -- .. end elseif not string.find(c, "%d") then return "." else self:read_numeral(ls, Token) return "TK_NUMBER" end ---------------------------------------------------------------- elseif c == "EOZ" then return "TK_EOS" ---------------------------------------------------------------- else -- default if string.find(c, "%s") then -- lua_assert(self:currIsNewline(ls)) self:nextc(ls) elseif string.find(c, "%d") then self:read_numeral(ls, Token) return "TK_NUMBER" elseif string.find(c, "[_%a]") then -- identifier or reserved word repeat c = self:save_and_next(ls) until c == "EOZ" or not string.find(c, "[_%w]") local ts = ls.buff local tok = self.enums[ts] if tok then return tok end -- reserved word? Token.seminfo = ts return "TK_NAME" else self:nextc(ls) return c -- single-char tokens (+ - / ...) end ---------------------------------------------------------------- end--if c end--while end --dofile("lopcodes.lua") --[[ =========================================================================== We assume that instructions are unsigned numbers. All instructions have an opcode in the first 6 bits. Instructions can have the following fields: 'A' : 8 bits 'B' : 9 bits 'C' : 9 bits 'Bx' : 18 bits ('B' and 'C' together) 'sBx' : signed Bx A signed argument is represented in excess K; that is, the number value is the unsigned value minus K. K is exactly the maximum value for that argument (so that -max is represented by 0, and +max is represented by 2*max), which is half the maximum for the corresponding unsigned argument. =========================================================================== --]] luaP.OpMode = { iABC = 0, iABx = 1, iAsBx = 2 } -- basic instruction format ------------------------------------------------------------------------ -- size and position of opcode arguments. -- * WARNING size and position is hard-coded elsewhere in this script ------------------------------------------------------------------------ luaP.SIZE_C = 9 luaP.SIZE_B = 9 luaP.SIZE_Bx = luaP.SIZE_C + luaP.SIZE_B luaP.SIZE_A = 8 luaP.SIZE_OP = 6 luaP.POS_OP = 0 luaP.POS_A = luaP.POS_OP + luaP.SIZE_OP luaP.POS_C = luaP.POS_A + luaP.SIZE_A luaP.POS_B = luaP.POS_C + luaP.SIZE_C luaP.POS_Bx = luaP.POS_C ------------------------------------------------------------------------ -- limits for opcode arguments. -- we use (signed) int to manipulate most arguments, -- so they must fit in LUAI_BITSINT-1 bits (-1 for sign) ------------------------------------------------------------------------ -- removed "#if SIZE_Bx < BITS_INT-1" test, assume this script is -- running on a Lua VM with double or int as LUA_NUMBER luaP.MAXARG_Bx = math.ldexp(1, luaP.SIZE_Bx) - 1 luaP.MAXARG_sBx = math.floor(luaP.MAXARG_Bx / 2) -- 'sBx' is signed luaP.MAXARG_A = math.ldexp(1, luaP.SIZE_A) - 1 luaP.MAXARG_B = math.ldexp(1, luaP.SIZE_B) - 1 luaP.MAXARG_C = math.ldexp(1, luaP.SIZE_C) - 1 -- creates a mask with 'n' 1 bits at position 'p' -- MASK1(n,p) deleted, not required -- creates a mask with 'n' 0 bits at position 'p' -- MASK0(n,p) deleted, not required --[[-------------------------------------------------------------------- Visual representation for reference: 31 | | | 0 bit position +-----+-----+-----+----------+ | B | C | A | Opcode | iABC format +-----+-----+-----+----------+ - 9 - 9 - 8 - 6 - field sizes +-----+-----+-----+----------+ | [s]Bx | A | Opcode | iABx | iAsBx format +-----+-----+-----+----------+ ----------------------------------------------------------------------]] ------------------------------------------------------------------------ -- the following macros help to manipulate instructions -- * changed to a table object representation, very clean compared to -- the [nightmare] alternatives of using a number or a string -- * Bx is a separate element from B and C, since there is never a need -- to split Bx in the parser or code generator ------------------------------------------------------------------------ -- these accept or return opcodes in the form of string names function luaP:GET_OPCODE(i) return self.ROpCode[i.OP] end function luaP:SET_OPCODE(i, o) i.OP = self.OpCode[o] end function luaP:GETARG_A(i) return i.A end function luaP:SETARG_A(i, u) i.A = u end function luaP:GETARG_B(i) return i.B end function luaP:SETARG_B(i, b) i.B = b end function luaP:GETARG_C(i) return i.C end function luaP:SETARG_C(i, b) i.C = b end function luaP:GETARG_Bx(i) return i.Bx end function luaP:SETARG_Bx(i, b) i.Bx = b end function luaP:GETARG_sBx(i) return i.Bx - self.MAXARG_sBx end function luaP:SETARG_sBx(i, b) i.Bx = b + self.MAXARG_sBx end function luaP:CREATE_ABC(o,a,b,c) return {OP = self.OpCode[o], A = a, B = b, C = c} end function luaP:CREATE_ABx(o,a,bc) return {OP = self.OpCode[o], A = a, Bx = bc} end ------------------------------------------------------------------------ -- create an instruction from a number (for OP_SETLIST) ------------------------------------------------------------------------ function luaP:CREATE_Inst(c) local o = c % 64 c = (c - o) / 64 local a = c % 256 c = (c - a) / 256 return self:CREATE_ABx(o, a, c) end ------------------------------------------------------------------------ -- returns a 4-char string little-endian encoded form of an instruction ------------------------------------------------------------------------ function luaP:Instruction(i) if i.Bx then -- change to OP/A/B/C format i.C = i.Bx % 512 i.B = (i.Bx - i.C) / 512 end local I = i.A * 64 + i.OP local c0 = I % 256 I = i.C * 64 + (I - c0) / 256 -- 6 bits of A left local c1 = I % 256 I = i.B * 128 + (I - c1) / 256 -- 7 bits of C left local c2 = I % 256 local c3 = (I - c2) / 256 return string.char(c0, c1, c2, c3) end ------------------------------------------------------------------------ -- decodes a 4-char little-endian string into an instruction struct ------------------------------------------------------------------------ function luaP:DecodeInst(x) local byte = string.byte local i = {} local I = byte(x, 1) local op = I % 64 i.OP = op I = byte(x, 2) * 4 + (I - op) / 64 -- 2 bits of c0 left local a = I % 256 i.A = a I = byte(x, 3) * 4 + (I - a) / 256 -- 2 bits of c1 left local c = I % 512 i.C = c i.B = byte(x, 4) * 2 + (I - c) / 512 -- 1 bits of c2 left local opmode = self.OpMode[tonumber(string.sub(self.opmodes[op + 1], 7, 7))] if opmode ~= "iABC" then i.Bx = i.B * 512 + i.C end return i end ------------------------------------------------------------------------ -- Macros to operate RK indices -- * these use arithmetic instead of bit ops ------------------------------------------------------------------------ -- this bit 1 means constant (0 means register) luaP.BITRK = math.ldexp(1, luaP.SIZE_B - 1) -- test whether value is a constant function luaP:ISK(x) return x >= self.BITRK end -- gets the index of the constant function luaP:INDEXK(r) return x - self.BITRK end luaP.MAXINDEXRK = luaP.BITRK - 1 -- code a constant index as a RK value function luaP:RKASK(x) return x + self.BITRK end ------------------------------------------------------------------------ -- invalid register that fits in 8 bits ------------------------------------------------------------------------ luaP.NO_REG = luaP.MAXARG_A ------------------------------------------------------------------------ -- R(x) - register -- Kst(x) - constant (in constant table) -- RK(x) == if ISK(x) then Kst(INDEXK(x)) else R(x) ------------------------------------------------------------------------ ------------------------------------------------------------------------ -- grep "ORDER OP" if you change these enums ------------------------------------------------------------------------ --[[-------------------------------------------------------------------- Lua virtual machine opcodes (enum OpCode): ------------------------------------------------------------------------ name args description ------------------------------------------------------------------------ OP_MOVE A B R(A) := R(B) OP_LOADK A Bx R(A) := Kst(Bx) OP_LOADBOOL A B C R(A) := (Bool)B; if (C) pc++ OP_LOADNIL A B R(A) := ... := R(B) := nil OP_GETUPVAL A B R(A) := UpValue[B] OP_GETGLOBAL A Bx R(A) := Gbl[Kst(Bx)] OP_GETTABLE A B C R(A) := R(B)[RK(C)] OP_SETGLOBAL A Bx Gbl[Kst(Bx)] := R(A) OP_SETUPVAL A B UpValue[B] := R(A) OP_SETTABLE A B C R(A)[RK(B)] := RK(C) OP_NEWTABLE A B C R(A) := {} (size = B,C) OP_SELF A B C R(A+1) := R(B); R(A) := R(B)[RK(C)] OP_ADD A B C R(A) := RK(B) + RK(C) OP_SUB A B C R(A) := RK(B) - RK(C) OP_MUL A B C R(A) := RK(B) * RK(C) OP_DIV A B C R(A) := RK(B) / RK(C) OP_MOD A B C R(A) := RK(B) % RK(C) OP_POW A B C R(A) := RK(B) ^ RK(C) OP_UNM A B R(A) := -R(B) OP_NOT A B R(A) := not R(B) OP_LEN A B R(A) := length of R(B) OP_CONCAT A B C R(A) := R(B).. ... ..R(C) OP_JMP sBx pc+=sBx OP_EQ A B C if ((RK(B) == RK(C)) ~= A) then pc++ OP_LT A B C if ((RK(B) < RK(C)) ~= A) then pc++ OP_LE A B C if ((RK(B) <= RK(C)) ~= A) then pc++ OP_TEST A C if not (R(A) <=> C) then pc++ OP_TESTSET A B C if (R(B) <=> C) then R(A) := R(B) else pc++ OP_CALL A B C R(A), ... ,R(A+C-2) := R(A)(R(A+1), ... ,R(A+B-1)) OP_TAILCALL A B C return R(A)(R(A+1), ... ,R(A+B-1)) OP_RETURN A B return R(A), ... ,R(A+B-2) (see note) OP_FORLOOP A sBx R(A)+=R(A+2); if R(A) =) R(A) OP_CLOSURE A Bx R(A) := closure(KPROTO[Bx], R(A), ... ,R(A+n)) OP_VARARG A B R(A), R(A+1), ..., R(A+B-1) = vararg ----------------------------------------------------------------------]] luaP.opnames = {} -- opcode names luaP.OpCode = {} -- lookup name -> number luaP.ROpCode = {} -- lookup number -> name ------------------------------------------------------------------------ -- ORDER OP ------------------------------------------------------------------------ local i = 0 for v in string.gmatch([[ MOVE LOADK LOADBOOL LOADNIL GETUPVAL GETGLOBAL GETTABLE SETGLOBAL SETUPVAL SETTABLE NEWTABLE SELF ADD SUB MUL DIV MOD POW UNM NOT LEN CONCAT JMP EQ LT LE TEST TESTSET CALL TAILCALL RETURN FORLOOP FORPREP TFORLOOP SETLIST CLOSE CLOSURE VARARG ]], "%S+") do local n = "OP_"..v luaP.opnames[i] = v luaP.OpCode[n] = i luaP.ROpCode[i] = n i = i + 1 end luaP.NUM_OPCODES = i --[[ =========================================================================== Notes: (*) In OP_CALL, if (B == 0) then B = top. C is the number of returns - 1, and can be 0: OP_CALL then sets 'top' to last_result+1, so next open instruction (OP_CALL, OP_RETURN, OP_SETLIST) may use 'top'. (*) In OP_VARARG, if (B == 0) then use actual number of varargs and set top (like in OP_CALL with C == 0). (*) In OP_RETURN, if (B == 0) then return up to 'top' (*) In OP_SETLIST, if (B == 0) then B = 'top'; if (C == 0) then next 'instruction' is real C (*) For comparisons, A specifies what condition the test should accept (true or false). (*) All 'skips' (pc++) assume that next instruction is a jump =========================================================================== --]] --[[-------------------------------------------------------------------- masks for instruction properties. The format is: bits 0-1: op mode bits 2-3: C arg mode bits 4-5: B arg mode bit 6: instruction set register A bit 7: operator is a test for OpArgMask: OpArgN - argument is not used OpArgU - argument is used OpArgR - argument is a register or a jump offset OpArgK - argument is a constant or register/constant ----------------------------------------------------------------------]] -- was enum OpArgMask luaP.OpArgMask = { OpArgN = 0, OpArgU = 1, OpArgR = 2, OpArgK = 3 } ------------------------------------------------------------------------ -- e.g. to compare with symbols, luaP:getOpMode(...) == luaP.OpCode.iABC -- * accepts opcode parameter as strings, e.g. "OP_MOVE" ------------------------------------------------------------------------ function luaP:getOpMode(m) return self.opmodes[self.OpCode[m]] % 4 end function luaP:getBMode(m) return math.floor(self.opmodes[self.OpCode[m]] / 16) % 4 end function luaP:getCMode(m) return math.floor(self.opmodes[self.OpCode[m]] / 4) % 4 end function luaP:testAMode(m) return math.floor(self.opmodes[self.OpCode[m]] / 64) % 2 end function luaP:testTMode(m) return math.floor(self.opmodes[self.OpCode[m]] / 128) end -- luaP_opnames[] is set above, as the luaP.opnames table -- number of list items to accumulate before a SETLIST instruction luaP.LFIELDS_PER_FLUSH = 50 ------------------------------------------------------------------------ -- build instruction properties array -- * deliberately coded to look like the C equivalent ------------------------------------------------------------------------ local function opmode(t, a, b, c, m) local luaP = luaP return t * 128 + a * 64 + luaP.OpArgMask[b] * 16 + luaP.OpArgMask[c] * 4 + luaP.OpMode[m] end -- ORDER OP luaP.opmodes = { -- T A B C mode opcode opmode(0, 1, "OpArgK", "OpArgN", "iABx"), -- OP_LOADK opmode(0, 1, "OpArgU", "OpArgU", "iABC"), -- OP_LOADBOOL opmode(0, 1, "OpArgR", "OpArgN", "iABC"), -- OP_LOADNIL opmode(0, 1, "OpArgU", "OpArgN", "iABC"), -- OP_GETUPVAL opmode(0, 1, "OpArgK", "OpArgN", "iABx"), -- OP_GETGLOBAL opmode(0, 1, "OpArgR", "OpArgK", "iABC"), -- OP_GETTABLE opmode(0, 0, "OpArgK", "OpArgN", "iABx"), -- OP_SETGLOBAL opmode(0, 0, "OpArgU", "OpArgN", "iABC"), -- OP_SETUPVAL opmode(0, 0, "OpArgK", "OpArgK", "iABC"), -- OP_SETTABLE opmode(0, 1, "OpArgU", "OpArgU", "iABC"), -- OP_NEWTABLE opmode(0, 1, "OpArgR", "OpArgK", "iABC"), -- OP_SELF opmode(0, 1, "OpArgK", "OpArgK", "iABC"), -- OP_ADD opmode(0, 1, "OpArgK", "OpArgK", "iABC"), -- OP_SUB opmode(0, 1, "OpArgK", "OpArgK", "iABC"), -- OP_MUL opmode(0, 1, "OpArgK", "OpArgK", "iABC"), -- OP_DIV opmode(0, 1, "OpArgK", "OpArgK", "iABC"), -- OP_MOD opmode(0, 1, "OpArgK", "OpArgK", "iABC"), -- OP_POW opmode(0, 1, "OpArgR", "OpArgN", "iABC"), -- OP_UNM opmode(0, 1, "OpArgR", "OpArgN", "iABC"), -- OP_NOT opmode(0, 1, "OpArgR", "OpArgN", "iABC"), -- OP_LEN opmode(0, 1, "OpArgR", "OpArgR", "iABC"), -- OP_CONCAT opmode(0, 0, "OpArgR", "OpArgN", "iAsBx"), -- OP_JMP opmode(1, 0, "OpArgK", "OpArgK", "iABC"), -- OP_EQ opmode(1, 0, "OpArgK", "OpArgK", "iABC"), -- OP_LT opmode(1, 0, "OpArgK", "OpArgK", "iABC"), -- OP_LE opmode(1, 1, "OpArgR", "OpArgU", "iABC"), -- OP_TEST opmode(1, 1, "OpArgR", "OpArgU", "iABC"), -- OP_TESTSET opmode(0, 1, "OpArgU", "OpArgU", "iABC"), -- OP_CALL opmode(0, 1, "OpArgU", "OpArgU", "iABC"), -- OP_TAILCALL opmode(0, 0, "OpArgU", "OpArgN", "iABC"), -- OP_RETURN opmode(0, 1, "OpArgR", "OpArgN", "iAsBx"), -- OP_FORLOOP opmode(0, 1, "OpArgR", "OpArgN", "iAsBx"), -- OP_FORPREP opmode(1, 0, "OpArgN", "OpArgU", "iABC"), -- OP_TFORLOOP opmode(0, 0, "OpArgU", "OpArgU", "iABC"), -- OP_SETLIST opmode(0, 0, "OpArgN", "OpArgN", "iABC"), -- OP_CLOSE opmode(0, 1, "OpArgU", "OpArgN", "iABx"), -- OP_CLOSURE opmode(0, 1, "OpArgU", "OpArgN", "iABC"), -- OP_VARARG } -- an awkward way to set a zero-indexed table... luaP.opmodes[0] = opmode(0, 1, "OpArgR", "OpArgN", "iABC") -- OP_MOVE --dofile("ldump.lua") --requires luaP -- mark for precompiled code ('Lua') (from lua.h) luaU.LUA_SIGNATURE = "\27Lua" -- constants used by dumper (from lua.h) luaU.LUA_TNUMBER = 3 luaU.LUA_TSTRING = 4 luaU.LUA_TNIL = 0 luaU.LUA_TBOOLEAN = 1 luaU.LUA_TNONE = -1 -- constants for header of binary files (from lundump.h) luaU.LUAC_VERSION = 0x51 -- this is Lua 5.1 luaU.LUAC_FORMAT = 0 -- this is the official format luaU.LUAC_HEADERSIZE = 12 -- size of header of binary files --[[-------------------------------------------------------------------- -- Additional functions to handle chunk writing -- * to use make_setS and make_setF, see test_ldump.lua elsewhere ----------------------------------------------------------------------]] ------------------------------------------------------------------------ -- create a chunk writer that writes to a string -- * returns the writer function and a table containing the string -- * to get the final result, look in buff.data ------------------------------------------------------------------------ function luaU:make_setS() local buff = {} buff.data = "" local writer = function(s, buff) -- chunk writer if not s then return 0 end buff.data = buff.data..s -- print (#buff.data, #s, string.byte(s,1,1), s) return 0 end return writer, buff end ------------------------------------------------------------------------ -- create a chunk writer that writes to a file -- * returns the writer function and a table containing the file handle -- * if a nil is passed, then writer should close the open file ------------------------------------------------------------------------ function luaU:make_setF(filename) local buff = {} buff.h = io.open(filename, "wb") if not buff.h then return nil end local writer = function(s, buff) -- chunk writer if not buff.h then return 0 end if not s then if buff.h:close() then return 0 end else if buff.h:write(s) then return 0 end end return 1 end return writer, buff end ------------------------------------------------------------------------ -- works like the lobject.h version except that TObject used in these -- scripts only has a 'value' field, no 'tt' field (native types used) ------------------------------------------------------------------------ function luaU:ttype(o) local tt = type(o.value) if tt == "number" then return self.LUA_TNUMBER elseif tt == "string" then return self.LUA_TSTRING elseif tt == "nil" then return self.LUA_TNIL elseif tt == "boolean" then return self.LUA_TBOOLEAN else return self.LUA_TNONE -- the rest should not appear end end ----------------------------------------------------------------------- -- converts a IEEE754 double number to an 8-byte little-endian string -- * luaU:from_double() and luaU:from_int() are adapted from ChunkBake -- * supports +/- Infinity, but not denormals or NaNs ----------------------------------------------------------------------- function luaU:from_double(x) local function grab_byte(v) local c = v % 256 return (v - c) / 256, string.char(c) end local sign = 0 if x < 0 then sign = 1; x = -x end local mantissa, exponent = math.frexp(x) if x == 0 then -- zero mantissa, exponent = 0, 0 elseif x == 1/0 then mantissa, exponent = 0, 2047 else mantissa = (mantissa * 2 - 1) * math.ldexp(0.5, 53) exponent = exponent + 1022 end local v, byte = "" -- convert to bytes x = math.floor(mantissa) for i = 1,6 do x, byte = grab_byte(x); v = v..byte -- 47:0 end x, byte = grab_byte(exponent * 16 + x); v = v..byte -- 55:48 x, byte = grab_byte(sign * 128 + x); v = v..byte -- 63:56 return v end ----------------------------------------------------------------------- -- converts a number to a little-endian 32-bit integer string -- * input value assumed to not overflow, can be signed/unsigned ----------------------------------------------------------------------- function luaU:from_int(x) local v = "" x = math.floor(x) if x < 0 then x = 4294967296 + x end -- ULONG_MAX+1 for i = 1, 4 do local c = x % 256 v = v..string.char(c); x = math.floor(x / 256) end return v end --[[-------------------------------------------------------------------- -- Functions to make a binary chunk -- * many functions have the size parameter removed, since output is -- in the form of a string and some sizes are implicit or hard-coded ----------------------------------------------------------------------]] --[[-------------------------------------------------------------------- -- struct DumpState: -- L -- lua_State (not used in this script) -- writer -- lua_Writer (chunk writer function) -- data -- void* (chunk writer context or data already written) -- strip -- if true, don't write any debug information -- status -- if non-zero, an error has occured ----------------------------------------------------------------------]] ------------------------------------------------------------------------ -- dumps a block of bytes -- * lua_unlock(D.L), lua_lock(D.L) unused ------------------------------------------------------------------------ function luaU:DumpBlock(b, D) if D.status == 0 then -- lua_unlock(D->L); D.status = D.write(b, D.data) -- lua_lock(D->L); end end ------------------------------------------------------------------------ -- dumps a char ------------------------------------------------------------------------ function luaU:DumpChar(y, D) self:DumpBlock(string.char(y), D) end ------------------------------------------------------------------------ -- dumps a 32-bit signed or unsigned integer (for int) (hard-coded) ------------------------------------------------------------------------ function luaU:DumpInt(x, D) self:DumpBlock(self:from_int(x), D) end ------------------------------------------------------------------------ -- dumps a 32-bit signed or unsigned integer (for int) (hard-coded) ------------------------------------------------------------------------ function luaU:DumpSizeT(x, D) self:DumpBlock(self:from_int(x), D) self:DumpBlock(self:from_int(0), D) end ------------------------------------------------------------------------ -- dumps a lua_Number (hard-coded as a double) ------------------------------------------------------------------------ function luaU:DumpNumber(x, D) self:DumpBlock(self:from_double(x), D) end ------------------------------------------------------------------------ -- dumps a Lua string (size type is hard-coded) ------------------------------------------------------------------------ function luaU:DumpString(s, D) if s == nil then self:DumpSizeT(0, D) else s = s.."\0" -- include trailing '\0' self:DumpSizeT(#s, D) self:DumpBlock(s, D) end end ------------------------------------------------------------------------ -- dumps instruction block from function prototype ------------------------------------------------------------------------ function luaU:DumpCode(f, D) local n = f.sizecode --was DumpVector self:DumpInt(n, D) for i = 0, n - 1 do self:DumpBlock(luaP:Instruction(f.code[i]), D) end end ------------------------------------------------------------------------ -- dump constant pool from function prototype -- * bvalue(o), nvalue(o) and rawtsvalue(o) macros removed ------------------------------------------------------------------------ function luaU:DumpConstants(f, D) local n = f.sizek self:DumpInt(n, D) for i = 0, n - 1 do local o = f.k[i] -- TValue local tt = self:ttype(o) self:DumpChar(tt, D) if tt == self.LUA_TNIL then elseif tt == self.LUA_TBOOLEAN then self:DumpChar(o.value and 1 or 0, D) elseif tt == self.LUA_TNUMBER then self:DumpNumber(o.value, D) elseif tt == self.LUA_TSTRING then self:DumpString(o.value, D) else --lua_assert(0) -- cannot happen end end n = f.sizep self:DumpInt(n, D) for i = 0, n - 1 do self:DumpFunction(f.p[i], f.source, D) end end ------------------------------------------------------------------------ -- dump debug information ------------------------------------------------------------------------ function luaU:DumpDebug(f, D) local n n = D.strip and 0 or f.sizelineinfo -- dump line information --was DumpVector self:DumpInt(n, D) for i = 0, n - 1 do self:DumpInt(f.lineinfo[i], D) end n = D.strip and 0 or f.sizelocvars -- dump local information self:DumpInt(n, D) for i = 0, n - 1 do self:DumpString(f.locvars[i].varname, D) self:DumpInt(f.locvars[i].startpc, D) self:DumpInt(f.locvars[i].endpc, D) end n = D.strip and 0 or f.sizeupvalues -- dump upvalue information self:DumpInt(n, D) for i = 0, n - 1 do self:DumpString(f.upvalues[i], D) end end ------------------------------------------------------------------------ -- dump child function prototypes from function prototype ------------------------------------------------------------------------ function luaU:DumpFunction(f, p, D) local source = f.source if source == p or D.strip then source = nil end self:DumpString(source, D) self:DumpInt(f.lineDefined, D) self:DumpInt(f.lastlinedefined, D) self:DumpChar(f.nups, D) self:DumpChar(f.numparams, D) self:DumpChar(f.is_vararg, D) self:DumpChar(f.maxstacksize, D) self:DumpCode(f, D) self:DumpConstants(f, D) self:DumpDebug(f, D) end ------------------------------------------------------------------------ -- dump Lua header section (some sizes hard-coded) ------------------------------------------------------------------------ function luaU:DumpHeader(D) local h = self:header() assert(#h == self.LUAC_HEADERSIZE) -- fixed buffer now an assert self:DumpBlock(h, D) end ------------------------------------------------------------------------ -- make header (from lundump.c) -- returns the header string ------------------------------------------------------------------------ function luaU:header() local x = 1 return self.LUA_SIGNATURE.. string.char( self.LUAC_VERSION, self.LUAC_FORMAT, x, -- endianness (1=little) 4, -- sizeof(int) size_size_t, -- sizeof(size_t) 4, -- sizeof(Instruction) 8, -- sizeof(lua_Number) 0) -- is lua_Number integral? end ------------------------------------------------------------------------ -- dump Lua function as precompiled chunk -- (lua_State* L, const Proto* f, lua_Writer w, void* data, int strip) -- * w, data are created from make_setS, make_setF ------------------------------------------------------------------------ function luaU:dump(L, f, w, data, strip) local D = {} -- DumpState D.L = L D.write = w D.data = data D.strip = strip D.status = 0 self:DumpHeader(D) self:DumpFunction(f, nil, D) -- added: for a chunk writer writing to a file, this final call with -- nil data is to indicate to the writer to close the file D.write(nil, D.data) return D.status end --dofile("lcode.lua") ------------------------------------------------------------------------ -- constants used by code generator ------------------------------------------------------------------------ -- maximum stack for a Lua function luaK.MAXSTACK = 250 -- (from llimits.h) --[[-------------------------------------------------------------------- -- other functions ----------------------------------------------------------------------]] ------------------------------------------------------------------------ -- emulation of TValue macros (these are from lobject.h) -- * TValue is a table since lcode passes references around -- * tt member field removed, using Lua's type() instead -- * for setsvalue, sethvalue, parameter L (deleted here) in lobject.h -- is used in an assert for testing, see checkliveness(g,obj) ------------------------------------------------------------------------ function luaK:ttisnumber(o) if o then return type(o.value) == "number" else return false end end function luaK:nvalue(o) return o.value end function luaK:setnilvalue(o) o.value = nil end function luaK:setsvalue(o, x) o.value = x end luaK.setnvalue = luaK.setsvalue luaK.sethvalue = luaK.setsvalue luaK.setbvalue = luaK.setsvalue ------------------------------------------------------------------------ -- The luai_num* macros define the primitive operations over numbers. -- * this is not the entire set of primitive operations from luaconf.h -- * used in luaK:constfolding() ------------------------------------------------------------------------ function luaK:numadd(a, b) return a + b end function luaK:numsub(a, b) return a - b end function luaK:nummul(a, b) return a * b end function luaK:numdiv(a, b) return a / b end function luaK:nummod(a, b) return a % b end -- ((a) - floor((a)/(b))*(b)) /* actual, for reference */ function luaK:numpow(a, b) return a ^ b end function luaK:numunm(a) return -a end function luaK:numisnan(a) return not a == a end -- a NaN cannot equal another NaN --[[-------------------------------------------------------------------- -- code generator functions ----------------------------------------------------------------------]] ------------------------------------------------------------------------ -- Marks the end of a patch list. It is an invalid value both as an absolute -- address, and as a list link (would link an element to itself). ------------------------------------------------------------------------ luaK.NO_JUMP = -1 ------------------------------------------------------------------------ -- grep "ORDER OPR" if you change these enums ------------------------------------------------------------------------ luaK.BinOpr = { OPR_ADD = 0, OPR_SUB = 1, OPR_MUL = 2, OPR_DIV = 3, OPR_MOD = 4, OPR_POW = 5, OPR_CONCAT = 6, OPR_NE = 7, OPR_EQ = 8, OPR_LT = 9, OPR_LE = 10, OPR_GT = 11, OPR_GE = 12, OPR_AND = 13, OPR_OR = 14, OPR_NOBINOPR = 15, } -- * UnOpr is used by luaK:prefix's op argument, but not directly used -- because the function receives the symbols as strings, e.g. "OPR_NOT" luaK.UnOpr = { OPR_MINUS = 0, OPR_NOT = 1, OPR_LEN = 2, OPR_NOUNOPR = 3 } ------------------------------------------------------------------------ -- returns the instruction object for given e (expdesc), was a macro ------------------------------------------------------------------------ function luaK:getcode(fs, e) return fs.f.code[e.info] end ------------------------------------------------------------------------ -- codes an instruction with a signed Bx (sBx) field, was a macro -- * used in luaK:jump(), (lparser) luaY:forbody() ------------------------------------------------------------------------ function luaK:codeAsBx(fs, o, A, sBx) return self:codeABx(fs, o, A, sBx + luaP.MAXARG_sBx) end ------------------------------------------------------------------------ -- set the expdesc e instruction for multiple returns, was a macro ------------------------------------------------------------------------ function luaK:setmultret(fs, e) self:setreturns(fs, e, luaY.LUA_MULTRET) end ------------------------------------------------------------------------ -- there is a jump if patch lists are not identical, was a macro -- * used in luaK:exp2reg(), luaK:exp2anyreg(), luaK:exp2val() ------------------------------------------------------------------------ function luaK:hasjumps(e) return e.t ~= e.f end ------------------------------------------------------------------------ -- true if the expression is a constant number (for constant folding) -- * used in constfolding(), infix() ------------------------------------------------------------------------ function luaK:isnumeral(e) return e.k == "VKNUM" and e.t == self.NO_JUMP and e.f == self.NO_JUMP end ------------------------------------------------------------------------ -- codes loading of nil, optimization done if consecutive locations -- * used in luaK:discharge2reg(), (lparser) luaY:adjust_assign() ------------------------------------------------------------------------ function luaK:_nil(fs, from, n) if fs.pc > fs.lasttarget then -- no jumps to current position? if fs.pc == 0 then -- function start? if from >= fs.nactvar then return -- positions are already clean end else local previous = fs.f.code[fs.pc - 1] if luaP:GET_OPCODE(previous) == "OP_LOADNIL" then local pfrom = luaP:GETARG_A(previous) local pto = luaP:GETARG_B(previous) if pfrom <= from and from <= pto + 1 then -- can connect both? if from + n - 1 > pto then luaP:SETARG_B(previous, from + n - 1) end return end end end end self:codeABC(fs, "OP_LOADNIL", from, from + n - 1, 0) -- else no optimization end ------------------------------------------------------------------------ -- -- * used in multiple locations ------------------------------------------------------------------------ function luaK:jump(fs) local jpc = fs.jpc -- save list of jumps to here fs.jpc = self.NO_JUMP local j = self:codeAsBx(fs, "OP_JMP", 0, self.NO_JUMP) j = self:concat(fs, j, jpc) -- keep them on hold return j end ------------------------------------------------------------------------ -- codes a RETURN instruction -- * used in luaY:close_func(), luaY:retstat() ------------------------------------------------------------------------ function luaK:ret(fs, first, nret) self:codeABC(fs, "OP_RETURN", first, nret + 1, 0) end ------------------------------------------------------------------------ -- -- * used in luaK:jumponcond(), luaK:codecomp() ------------------------------------------------------------------------ function luaK:condjump(fs, op, A, B, C) self:codeABC(fs, op, A, B, C) return self:jump(fs) end ------------------------------------------------------------------------ -- -- * used in luaK:patchlistaux(), luaK:concat() ------------------------------------------------------------------------ function luaK:fixjump(fs, pc, dest) local jmp = fs.f.code[pc] local offset = dest - (pc + 1) lua_assert(dest ~= self.NO_JUMP) if math.abs(offset) > luaP.MAXARG_sBx then luaX:syntaxerror(fs.ls, "control structure too long") end luaP:SETARG_sBx(jmp, offset) end ------------------------------------------------------------------------ -- returns current 'pc' and marks it as a jump target (to avoid wrong -- optimizations with consecutive instructions not in the same basic block). -- * used in multiple locations -- * fs.lasttarget tested only by luaK:_nil() when optimizing OP_LOADNIL ------------------------------------------------------------------------ function luaK:getlabel(fs) fs.lasttarget = fs.pc return fs.pc end ------------------------------------------------------------------------ -- -- * used in luaK:need_value(), luaK:removevalues(), luaK:patchlistaux(), -- luaK:concat() ------------------------------------------------------------------------ function luaK:getjump(fs, pc) local offset = luaP:GETARG_sBx(fs.f.code[pc]) if offset == self.NO_JUMP then -- point to itself represents end of list return self.NO_JUMP -- end of list else return (pc + 1) + offset -- turn offset into absolute position end end ------------------------------------------------------------------------ -- -- * used in luaK:need_value(), luaK:patchtestreg(), luaK:invertjump() ------------------------------------------------------------------------ function luaK:getjumpcontrol(fs, pc) local pi = fs.f.code[pc] local ppi = fs.f.code[pc - 1] if pc >= 1 and luaP:testTMode(luaP:GET_OPCODE(ppi)) ~= 0 then return ppi else return pi end end ------------------------------------------------------------------------ -- check whether list has any jump that do not produce a value -- (or produce an inverted value) -- * return value changed to boolean -- * used only in luaK:exp2reg() ------------------------------------------------------------------------ function luaK:need_value(fs, list) while list ~= self.NO_JUMP do local i = self:getjumpcontrol(fs, list) if luaP:GET_OPCODE(i) ~= "OP_TESTSET" then return true end list = self:getjump(fs, list) end return false -- not found end ------------------------------------------------------------------------ -- -- * used in luaK:removevalues(), luaK:patchlistaux() ------------------------------------------------------------------------ function luaK:patchtestreg(fs, node, reg) local i = self:getjumpcontrol(fs, node) if luaP:GET_OPCODE(i) ~= "OP_TESTSET" then return false -- cannot patch other instructions end if reg ~= luaP.NO_REG and reg ~= luaP:GETARG_B(i) then luaP:SETARG_A(i, reg) else -- no register to put value or register already has the value -- due to use of a table as i, i cannot be replaced by another table -- so the following is required; there is no change to ARG_C luaP:SET_OPCODE(i, "OP_TEST") local b = luaP:GETARG_B(i) luaP:SETARG_A(i, b) luaP:SETARG_B(i, 0) -- *i = CREATE_ABC(OP_TEST, GETARG_B(*i), 0, GETARG_C(*i)); /* C */ end return true end ------------------------------------------------------------------------ -- -- * used only in luaK:codenot() ------------------------------------------------------------------------ function luaK:removevalues(fs, list) while list ~= self.NO_JUMP do self:patchtestreg(fs, list, luaP.NO_REG) list = self:getjump(fs, list) end end ------------------------------------------------------------------------ -- -- * used in luaK:dischargejpc(), luaK:patchlist(), luaK:exp2reg() ------------------------------------------------------------------------ function luaK:patchlistaux(fs, list, vtarget, reg, dtarget) while list ~= self.NO_JUMP do local _next = self:getjump(fs, list) if self:patchtestreg(fs, list, reg) then self:fixjump(fs, list, vtarget) else self:fixjump(fs, list, dtarget) -- jump to default target end list = _next end end ------------------------------------------------------------------------ -- -- * used only in luaK:code() ------------------------------------------------------------------------ function luaK:dischargejpc(fs) self:patchlistaux(fs, fs.jpc, fs.pc, luaP.NO_REG, fs.pc) fs.jpc = self.NO_JUMP end ------------------------------------------------------------------------ -- -- * used in (lparser) luaY:whilestat(), luaY:repeatstat(), luaY:forbody() ------------------------------------------------------------------------ function luaK:patchlist(fs, list, target) if target == fs.pc then self:patchtohere(fs, list) else lua_assert(target < fs.pc) self:patchlistaux(fs, list, target, luaP.NO_REG, target) end end ------------------------------------------------------------------------ -- -- * used in multiple locations ------------------------------------------------------------------------ function luaK:patchtohere(fs, list) self:getlabel(fs) fs.jpc = self:concat(fs, fs.jpc, list) end ------------------------------------------------------------------------ -- * l1 was a pointer, now l1 is returned and callee assigns the value -- * used in multiple locations ------------------------------------------------------------------------ function luaK:concat(fs, l1, l2) if l2 == self.NO_JUMP then return l1 elseif l1 == self.NO_JUMP then return l2 else local list = l1 local _next = self:getjump(fs, list) while _next ~= self.NO_JUMP do -- find last element list = _next _next = self:getjump(fs, list) end self:fixjump(fs, list, l2) end return l1 end ------------------------------------------------------------------------ -- -- * used in luaK:reserveregs(), (lparser) luaY:forlist() ------------------------------------------------------------------------ function luaK:checkstack(fs, n) local newstack = fs.freereg + n if newstack > fs.f.maxstacksize then if newstack >= self.MAXSTACK then luaX:syntaxerror(fs.ls, "function or expression too complex") end fs.f.maxstacksize = newstack end end ------------------------------------------------------------------------ -- -- * used in multiple locations ------------------------------------------------------------------------ function luaK:reserveregs(fs, n) self:checkstack(fs, n) fs.freereg = fs.freereg + n end ------------------------------------------------------------------------ -- -- * used in luaK:freeexp(), luaK:dischargevars() ------------------------------------------------------------------------ function luaK:freereg(fs, reg) if not luaP:ISK(reg) and reg >= fs.nactvar then fs.freereg = fs.freereg - 1 lua_assert(reg == fs.freereg) end end ------------------------------------------------------------------------ -- -- * used in multiple locations ------------------------------------------------------------------------ function luaK:freeexp(fs, e) if e.k == "VNONRELOC" then self:freereg(fs, e.info) end end ------------------------------------------------------------------------ -- * TODO NOTE implementation is not 100% correct, since the assert fails -- * luaH_set, setobj deleted; direct table access used instead -- * used in luaK:stringK(), luaK:numberK(), luaK:boolK(), luaK:nilK() ------------------------------------------------------------------------ function luaK:addk(fs, k, v) local L = fs.L local idx = fs.h[k.value] --TValue *idx = luaH_set(L, fs->h, k); /* C */ local f = fs.f if self:ttisnumber(idx) then --TODO this assert currently FAILS (last tested for 5.0.2) --lua_assert(fs.f.k[self:nvalue(idx)] == v) --lua_assert(luaO_rawequalObj(&fs->f->k[cast_int(nvalue(idx))], v)); /* C */ return self:nvalue(idx) else -- constant not found; create a new entry idx = {} self:setnvalue(idx, fs.nk) fs.h[k.value] = idx -- setnvalue(idx, cast_num(fs->nk)); /* C */ luaY:growvector(L, f.k, fs.nk, f.sizek, nil, luaP.MAXARG_Bx, "constant table overflow") -- loop to initialize empty f.k positions not required f.k[fs.nk] = v -- setobj(L, &f->k[fs->nk], v); /* C */ -- luaC_barrier(L, f, v); /* GC */ local nk = fs.nk fs.nk = fs.nk + 1 return nk end end ------------------------------------------------------------------------ -- creates and sets a string object -- * used in (lparser) luaY:codestring(), luaY:singlevar() ------------------------------------------------------------------------ function luaK:stringK(fs, s) local o = {} -- TValue self:setsvalue(o, s) return self:addk(fs, o, o) end ------------------------------------------------------------------------ -- creates and sets a number object -- * used in luaK:prefix() for negative (or negation of) numbers -- * used in (lparser) luaY:simpleexp(), luaY:fornum() ------------------------------------------------------------------------ function luaK:numberK(fs, r) local o = {} -- TValue self:setnvalue(o, r) return self:addk(fs, o, o) end ------------------------------------------------------------------------ -- creates and sets a boolean object -- * used only in luaK:exp2RK() ------------------------------------------------------------------------ function luaK:boolK(fs, b) local o = {} -- TValue self:setbvalue(o, b) return self:addk(fs, o, o) end ------------------------------------------------------------------------ -- creates and sets a nil object -- * used only in luaK:exp2RK() ------------------------------------------------------------------------ function luaK:nilK(fs) local k, v = {}, {} -- TValue self:setnilvalue(v) -- cannot use nil as key; instead use table itself to represent nil self:sethvalue(k, fs.h) return self:addk(fs, k, v) end ------------------------------------------------------------------------ -- -- * used in luaK:setmultret(), (lparser) luaY:adjust_assign() ------------------------------------------------------------------------ function luaK:setreturns(fs, e, nresults) if e.k == "VCALL" then -- expression is an open function call? luaP:SETARG_C(self:getcode(fs, e), nresults + 1) elseif e.k == "VVARARG" then luaP:SETARG_B(self:getcode(fs, e), nresults + 1); luaP:SETARG_A(self:getcode(fs, e), fs.freereg); luaK:reserveregs(fs, 1) end end ------------------------------------------------------------------------ -- -- * used in luaK:dischargevars(), (lparser) luaY:assignment() ------------------------------------------------------------------------ function luaK:setoneret(fs, e) if e.k == "VCALL" then -- expression is an open function call? e.k = "VNONRELOC" e.info = luaP:GETARG_A(self:getcode(fs, e)) elseif e.k == "VVARARG" then luaP:SETARG_B(self:getcode(fs, e), 2) e.k = "VRELOCABLE" -- can relocate its simple result end end ------------------------------------------------------------------------ -- -- * used in multiple locations ------------------------------------------------------------------------ function luaK:dischargevars(fs, e) local k = e.k if k == "VLOCAL" then e.k = "VNONRELOC" elseif k == "VUPVAL" then e.info = self:codeABC(fs, "OP_GETUPVAL", 0, e.info, 0) e.k = "VRELOCABLE" elseif k == "VGLOBAL" then e.info = self:codeABx(fs, "OP_GETGLOBAL", 0, e.info) e.k = "VRELOCABLE" elseif k == "VINDEXED" then self:freereg(fs, e.aux) self:freereg(fs, e.info) e.info = self:codeABC(fs, "OP_GETTABLE", 0, e.info, e.aux) e.k = "VRELOCABLE" elseif k == "VVARARG" or k == "VCALL" then self:setoneret(fs, e) else -- there is one value available (somewhere) end end ------------------------------------------------------------------------ -- -- * used only in luaK:exp2reg() ------------------------------------------------------------------------ function luaK:code_label(fs, A, b, jump) self:getlabel(fs) -- those instructions may be jump targets return self:codeABC(fs, "OP_LOADBOOL", A, b, jump) end ------------------------------------------------------------------------ -- -- * used in luaK:discharge2anyreg(), luaK:exp2reg() ------------------------------------------------------------------------ function luaK:discharge2reg(fs, e, reg) self:dischargevars(fs, e) local k = e.k if k == "VNIL" then self:_nil(fs, reg, 1) elseif k == "VFALSE" or k == "VTRUE" then self:codeABC(fs, "OP_LOADBOOL", reg, (e.k == "VTRUE") and 1 or 0, 0) elseif k == "VK" then self:codeABx(fs, "OP_LOADK", reg, e.info) elseif k == "VKNUM" then self:codeABx(fs, "OP_LOADK", reg, self:numberK(fs, e.nval)) elseif k == "VRELOCABLE" then local pc = self:getcode(fs, e) luaP:SETARG_A(pc, reg) elseif k == "VNONRELOC" then if reg ~= e.info then self:codeABC(fs, "OP_MOVE", reg, e.info, 0) end else lua_assert(e.k == "VVOID" or e.k == "VJMP") return -- nothing to do... end e.info = reg e.k = "VNONRELOC" end ------------------------------------------------------------------------ -- -- * used in luaK:jumponcond(), luaK:codenot() ------------------------------------------------------------------------ function luaK:discharge2anyreg(fs, e) if e.k ~= "VNONRELOC" then self:reserveregs(fs, 1) self:discharge2reg(fs, e, fs.freereg - 1) end end ------------------------------------------------------------------------ -- -- * used in luaK:exp2nextreg(), luaK:exp2anyreg(), luaK:storevar() ------------------------------------------------------------------------ function luaK:exp2reg(fs, e, reg) self:discharge2reg(fs, e, reg) if e.k == "VJMP" then e.t = self:concat(fs, e.t, e.info) -- put this jump in 't' list end if self:hasjumps(e) then local final -- position after whole expression local p_f = self.NO_JUMP -- position of an eventual LOAD false local p_t = self.NO_JUMP -- position of an eventual LOAD true if self:need_value(fs, e.t) or self:need_value(fs, e.f) then local fj = (e.k == "VJMP") and self.NO_JUMP or self:jump(fs) p_f = self:code_label(fs, reg, 0, 1) p_t = self:code_label(fs, reg, 1, 0) self:patchtohere(fs, fj) end final = self:getlabel(fs) self:patchlistaux(fs, e.f, final, reg, p_f) self:patchlistaux(fs, e.t, final, reg, p_t) end e.f, e.t = self.NO_JUMP, self.NO_JUMP e.info = reg e.k = "VNONRELOC" end ------------------------------------------------------------------------ -- -- * used in multiple locations ------------------------------------------------------------------------ function luaK:exp2nextreg(fs, e) self:dischargevars(fs, e) self:freeexp(fs, e) self:reserveregs(fs, 1) self:exp2reg(fs, e, fs.freereg - 1) end ------------------------------------------------------------------------ -- -- * used in multiple locations ------------------------------------------------------------------------ function luaK:exp2anyreg(fs, e) self:dischargevars(fs, e) if e.k == "VNONRELOC" then if not self:hasjumps(e) then -- exp is already in a register return e.info end if e.info >= fs.nactvar then -- reg. is not a local? self:exp2reg(fs, e, e.info) -- put value on it return e.info end end self:exp2nextreg(fs, e) -- default return e.info end ------------------------------------------------------------------------ -- -- * used in luaK:exp2RK(), luaK:prefix(), luaK:posfix() -- * used in (lparser) luaY:yindex() ------------------------------------------------------------------------ function luaK:exp2val(fs, e) if self:hasjumps(e) then self:exp2anyreg(fs, e) else self:dischargevars(fs, e) end end ------------------------------------------------------------------------ -- -- * used in multiple locations ------------------------------------------------------------------------ function luaK:exp2RK(fs, e) self:exp2val(fs, e) local k = e.k if k == "VKNUM" or k == "VTRUE" or k == "VFALSE" or k == "VNIL" then if fs.nk <= luaP.MAXINDEXRK then -- constant fit in RK operand? -- converted from a 2-deep ternary operator expression if e.k == "VNIL" then e.info = self:nilK(fs) else e.info = (e.k == "VKNUM") and self:numberK(fs, e.nval) or self:boolK(fs, e.k == "VTRUE") end e.k = "VK" return luaP:RKASK(e.info) end elseif k == "VK" then if e.info <= luaP.MAXINDEXRK then -- constant fit in argC? return luaP:RKASK(e.info) end else -- default end -- not a constant in the right range: put it in a register return self:exp2anyreg(fs, e) end ------------------------------------------------------------------------ -- -- * used in (lparser) luaY:assignment(), luaY:localfunc(), luaY:funcstat() ------------------------------------------------------------------------ function luaK:storevar(fs, var, ex) local k = var.k if k == "VLOCAL" then self:freeexp(fs, ex) self:exp2reg(fs, ex, var.info) return elseif k == "VUPVAL" then local e = self:exp2anyreg(fs, ex) self:codeABC(fs, "OP_SETUPVAL", e, var.info, 0) elseif k == "VGLOBAL" then local e = self:exp2anyreg(fs, ex) self:codeABx(fs, "OP_SETGLOBAL", e, var.info) elseif k == "VINDEXED" then local e = self:exp2RK(fs, ex) self:codeABC(fs, "OP_SETTABLE", var.info, var.aux, e) else lua_assert(0) -- invalid var kind to store end self:freeexp(fs, ex) end ------------------------------------------------------------------------ -- -- * used only in (lparser) luaY:primaryexp() ------------------------------------------------------------------------ function luaK:_self(fs, e, key) self:exp2anyreg(fs, e) self:freeexp(fs, e) local func = fs.freereg self:reserveregs(fs, 2) self:codeABC(fs, "OP_SELF", func, e.info, self:exp2RK(fs, key)) self:freeexp(fs, key) e.info = func e.k = "VNONRELOC" end ------------------------------------------------------------------------ -- -- * used in luaK:goiftrue(), luaK:codenot() ------------------------------------------------------------------------ function luaK:invertjump(fs, e) local pc = self:getjumpcontrol(fs, e.info) lua_assert(luaP:testTMode(luaP:GET_OPCODE(pc)) ~= 0 and luaP:GET_OPCODE(pc) ~= "OP_TESTSET" and luaP:GET_OPCODE(pc) ~= "OP_TEST") luaP:SETARG_A(pc, (luaP:GETARG_A(pc) == 0) and 1 or 0) end ------------------------------------------------------------------------ -- -- * used in luaK:goiftrue(), luaK:goiffalse() ------------------------------------------------------------------------ function luaK:jumponcond(fs, e, cond) if e.k == "VRELOCABLE" then local ie = self:getcode(fs, e) if luaP:GET_OPCODE(ie) == "OP_NOT" then fs.pc = fs.pc - 1 -- remove previous OP_NOT return self:condjump(fs, "OP_TEST", luaP:GETARG_B(ie), 0, cond and 0 or 1) end -- else go through end self:discharge2anyreg(fs, e) self:freeexp(fs, e) return self:condjump(fs, "OP_TESTSET", luaP.NO_REG, e.info, cond and 1 or 0) end ------------------------------------------------------------------------ -- -- * used in luaK:infix(), (lparser) luaY:cond() ------------------------------------------------------------------------ function luaK:goiftrue(fs, e) local pc -- pc of last jump self:dischargevars(fs, e) local k = e.k if k == "VK" or k == "VKNUM" or k == "VTRUE" then pc = self.NO_JUMP -- always true; do nothing elseif k == "VFALSE" then pc = self:jump(fs) -- always jump elseif k == "VJMP" then self:invertjump(fs, e) pc = e.info else pc = self:jumponcond(fs, e, false) end e.f = self:concat(fs, e.f, pc) -- insert last jump in `f' list self:patchtohere(fs, e.t) e.t = self.NO_JUMP end ------------------------------------------------------------------------ -- -- * used in luaK:infix() ------------------------------------------------------------------------ function luaK:goiffalse(fs, e) local pc -- pc of last jump self:dischargevars(fs, e) local k = e.k if k == "VNIL" or k == "VFALSE"then pc = self.NO_JUMP -- always false; do nothing elseif k == "VTRUE" then pc = self:jump(fs) -- always jump elseif k == "VJMP" then pc = e.info else pc = self:jumponcond(fs, e, true) end e.t = self:concat(fs, e.t, pc) -- insert last jump in `t' list self:patchtohere(fs, e.f) e.f = self.NO_JUMP end ------------------------------------------------------------------------ -- -- * used only in luaK:prefix() ------------------------------------------------------------------------ function luaK:codenot(fs, e) self:dischargevars(fs, e) local k = e.k if k == "VNIL" or k == "VFALSE" then e.k = "VTRUE" elseif k == "VK" or k == "VKNUM" or k == "VTRUE" then e.k = "VFALSE" elseif k == "VJMP" then self:invertjump(fs, e) elseif k == "VRELOCABLE" or k == "VNONRELOC" then self:discharge2anyreg(fs, e) self:freeexp(fs, e) e.info = self:codeABC(fs, "OP_NOT", 0, e.info, 0) e.k = "VRELOCABLE" else lua_assert(0) -- cannot happen end -- interchange true and false lists e.f, e.t = e.t, e.f self:removevalues(fs, e.f) self:removevalues(fs, e.t) end ------------------------------------------------------------------------ -- -- * used in (lparser) luaY:field(), luaY:primaryexp() ------------------------------------------------------------------------ function luaK:indexed(fs, t, k) t.aux = self:exp2RK(fs, k) t.k = "VINDEXED" end ------------------------------------------------------------------------ -- -- * used only in luaK:codearith() ------------------------------------------------------------------------ function luaK:constfolding(op, e1, e2) local r if not self:isnumeral(e1) or not self:isnumeral(e2) then return false end local v1 = e1.nval local v2 = e2.nval if op == "OP_ADD" then r = self:numadd(v1, v2) elseif op == "OP_SUB" then r = self:numsub(v1, v2) elseif op == "OP_MUL" then r = self:nummul(v1, v2) elseif op == "OP_DIV" then if v2 == 0 then return false end -- do not attempt to divide by 0 r = self:numdiv(v1, v2) elseif op == "OP_MOD" then if v2 == 0 then return false end -- do not attempt to divide by 0 r = self:nummod(v1, v2) elseif op == "OP_POW" then r = self:numpow(v1, v2) elseif op == "OP_UNM" then r = self:numunm(v1) elseif op == "OP_LEN" then return false -- no constant folding for 'len' else lua_assert(0) r = 0 end if self:numisnan(r) then return false end -- do not attempt to produce NaN e1.nval = r return true end ------------------------------------------------------------------------ -- -- * used in luaK:prefix(), luaK:posfix() ------------------------------------------------------------------------ function luaK:codearith(fs, op, e1, e2) if self:constfolding(op, e1, e2) then return else local o2 = (op ~= "OP_UNM" and op ~= "OP_LEN") and self:exp2RK(fs, e2) or 0 local o1 = self:exp2RK(fs, e1) if o1 > o2 then self:freeexp(fs, e1) self:freeexp(fs, e2) else self:freeexp(fs, e2) self:freeexp(fs, e1) end e1.info = self:codeABC(fs, op, 0, o1, o2) e1.k = "VRELOCABLE" end end ------------------------------------------------------------------------ -- -- * used only in luaK:posfix() ------------------------------------------------------------------------ function luaK:codecomp(fs, op, cond, e1, e2) local o1 = self:exp2RK(fs, e1) local o2 = self:exp2RK(fs, e2) self:freeexp(fs, e2) self:freeexp(fs, e1) if cond == 0 and op ~= "OP_EQ" then -- exchange args to replace by `<' or `<=' o1, o2 = o2, o1 -- o1 <==> o2 cond = 1 end e1.info = self:condjump(fs, op, cond, o1, o2) e1.k = "VJMP" end ------------------------------------------------------------------------ -- -- * used only in (lparser) luaY:subexpr() ------------------------------------------------------------------------ function luaK:prefix(fs, op, e) local e2 = {} -- expdesc e2.t, e2.f = self.NO_JUMP, self.NO_JUMP e2.k = "VKNUM" e2.nval = 0 if op == "OPR_MINUS" then if not self:isnumeral(e) then self:exp2anyreg(fs, e) -- cannot operate on non-numeric constants end self:codearith(fs, "OP_UNM", e, e2) elseif op == "OPR_NOT" then self:codenot(fs, e) elseif op == "OPR_LEN" then self:exp2anyreg(fs, e) -- cannot operate on constants self:codearith(fs, "OP_LEN", e, e2) else lua_assert(0) end end ------------------------------------------------------------------------ -- -- * used only in (lparser) luaY:subexpr() ------------------------------------------------------------------------ function luaK:infix(fs, op, v) if op == "OPR_AND" then self:goiftrue(fs, v) elseif op == "OPR_OR" then self:goiffalse(fs, v) elseif op == "OPR_CONCAT" then self:exp2nextreg(fs, v) -- operand must be on the 'stack' elseif op == "OPR_ADD" or op == "OPR_SUB" or op == "OPR_MUL" or op == "OPR_DIV" or op == "OPR_MOD" or op == "OPR_POW" then if not self:isnumeral(v) then self:exp2RK(fs, v) end else self:exp2RK(fs, v) end end ------------------------------------------------------------------------ -- -- * used only in (lparser) luaY:subexpr() ------------------------------------------------------------------------ -- table lookups to simplify testing luaK.arith_op = { OPR_ADD = "OP_ADD", OPR_SUB = "OP_SUB", OPR_MUL = "OP_MUL", OPR_DIV = "OP_DIV", OPR_MOD = "OP_MOD", OPR_POW = "OP_POW", } luaK.comp_op = { OPR_EQ = "OP_EQ", OPR_NE = "OP_EQ", OPR_LT = "OP_LT", OPR_LE = "OP_LE", OPR_GT = "OP_LT", OPR_GE = "OP_LE", } luaK.comp_cond = { OPR_EQ = 1, OPR_NE = 0, OPR_LT = 1, OPR_LE = 1, OPR_GT = 0, OPR_GE = 0, } function luaK:posfix(fs, op, e1, e2) -- needed because e1 = e2 doesn't copy values... -- * in 5.0.x, only k/info/aux/t/f copied, t for AND, f for OR -- but here, all elements are copied for completeness' sake local function copyexp(e1, e2) e1.k = e2.k e1.info = e2.info; e1.aux = e2.aux e1.nval = e2.nval e1.t = e2.t; e1.f = e2.f end if op == "OPR_AND" then lua_assert(e1.t == self.NO_JUMP) -- list must be closed self:dischargevars(fs, e2) e2.f = self:concat(fs, e2.f, e1.f) copyexp(e1, e2) elseif op == "OPR_OR" then lua_assert(e1.f == self.NO_JUMP) -- list must be closed self:dischargevars(fs, e2) e2.t = self:concat(fs, e2.t, e1.t) copyexp(e1, e2) elseif op == "OPR_CONCAT" then self:exp2val(fs, e2) if e2.k == "VRELOCABLE" and luaP:GET_OPCODE(self:getcode(fs, e2)) == "OP_CONCAT" then lua_assert(e1.info == luaP:GETARG_B(self:getcode(fs, e2)) - 1) self:freeexp(fs, e1) luaP:SETARG_B(self:getcode(fs, e2), e1.info) e1.k = "VRELOCABLE" e1.info = e2.info else self:exp2nextreg(fs, e2) -- operand must be on the 'stack' self:codearith(fs, "OP_CONCAT", e1, e2) end else -- the following uses a table lookup in place of conditionals local arith = self.arith_op[op] if arith then self:codearith(fs, arith, e1, e2) else local comp = self.comp_op[op] if comp then self:codecomp(fs, comp, self.comp_cond[op], e1, e2) else lua_assert(0) end end--if arith end--if op end ------------------------------------------------------------------------ -- adjusts debug information for last instruction written, in order to -- change the line where item comes into existence -- * used in (lparser) luaY:funcargs(), luaY:forbody(), luaY:funcstat() ------------------------------------------------------------------------ function luaK:fixline(fs, line) fs.f.lineinfo[fs.pc - 1] = line end ------------------------------------------------------------------------ -- general function to write an instruction into the instruction buffer, -- sets debug information too -- * used in luaK:codeABC(), luaK:codeABx() -- * called directly by (lparser) luaY:whilestat() ------------------------------------------------------------------------ function luaK:code(fs, i, line) local f = fs.f self:dischargejpc(fs) -- 'pc' will change -- put new instruction in code array luaY:growvector(fs.L, f.code, fs.pc, f.sizecode, nil, luaY.MAX_INT, "code size overflow") f.code[fs.pc] = i -- save corresponding line information luaY:growvector(fs.L, f.lineinfo, fs.pc, f.sizelineinfo, nil, luaY.MAX_INT, "code size overflow") f.lineinfo[fs.pc] = line local pc = fs.pc fs.pc = fs.pc + 1 return pc end ------------------------------------------------------------------------ -- writes an instruction of type ABC -- * calls luaK:code() ------------------------------------------------------------------------ function luaK:codeABC(fs, o, a, b, c) lua_assert(luaP:getOpMode(o) == luaP.OpMode.iABC) lua_assert(luaP:getBMode(o) ~= luaP.OpArgMask.OpArgN or b == 0) lua_assert(luaP:getCMode(o) ~= luaP.OpArgMask.OpArgN or c == 0) return self:code(fs, luaP:CREATE_ABC(o, a, b, c), fs.ls.lastline) end ------------------------------------------------------------------------ -- writes an instruction of type ABx -- * calls luaK:code(), called by luaK:codeAsBx() ------------------------------------------------------------------------ function luaK:codeABx(fs, o, a, bc) lua_assert(luaP:getOpMode(o) == luaP.OpMode.iABx or luaP:getOpMode(o) == luaP.OpMode.iAsBx) lua_assert(luaP:getCMode(o) == luaP.OpArgMask.OpArgN) return self:code(fs, luaP:CREATE_ABx(o, a, bc), fs.ls.lastline) end ------------------------------------------------------------------------ -- -- * used in (lparser) luaY:closelistfield(), luaY:lastlistfield() ------------------------------------------------------------------------ function luaK:setlist(fs, base, nelems, tostore) local c = math.floor((nelems - 1)/luaP.LFIELDS_PER_FLUSH) + 1 local b = (tostore == luaY.LUA_MULTRET) and 0 or tostore lua_assert(tostore ~= 0) if c <= luaP.MAXARG_C then self:codeABC(fs, "OP_SETLIST", base, b, c) else self:codeABC(fs, "OP_SETLIST", base, b, 0) self:code(fs, luaP:CREATE_Inst(c), fs.ls.lastline) end fs.freereg = base + 1 -- free registers with list values end --dofile("lparser.lua") --[[-------------------------------------------------------------------- -- Expression descriptor -- * expkind changed to string constants; luaY:assignment was the only -- function to use a relational operator with this enumeration -- VVOID -- no value -- VNIL -- no value -- VTRUE -- no value -- VFALSE -- no value -- VK -- info = index of constant in 'k' -- VKNUM -- nval = numerical value -- VLOCAL -- info = local register -- VUPVAL, -- info = index of upvalue in 'upvalues' -- VGLOBAL -- info = index of table; aux = index of global name in 'k' -- VINDEXED -- info = table register; aux = index register (or 'k') -- VJMP -- info = instruction pc -- VRELOCABLE -- info = instruction pc -- VNONRELOC -- info = result register -- VCALL -- info = instruction pc -- VVARARG -- info = instruction pc } ----------------------------------------------------------------------]] --[[-------------------------------------------------------------------- -- * expdesc in Lua 5.1.x has a union u and another struct s; this Lua -- implementation ignores all instances of u and s usage -- struct expdesc: -- k -- (enum: expkind) -- info, aux -- (int, int) -- nval -- (lua_Number) -- t -- patch list of 'exit when true' -- f -- patch list of 'exit when false' ----------------------------------------------------------------------]] --[[-------------------------------------------------------------------- -- struct upvaldesc: -- k -- (lu_byte) -- info -- (lu_byte) ----------------------------------------------------------------------]] --[[-------------------------------------------------------------------- -- state needed to generate code for a given function -- struct FuncState: -- f -- current function header (table: Proto) -- h -- table to find (and reuse) elements in 'k' (table: Table) -- prev -- enclosing function (table: FuncState) -- ls -- lexical state (table: LexState) -- L -- copy of the Lua state (table: lua_State) -- bl -- chain of current blocks (table: BlockCnt) -- pc -- next position to code (equivalent to 'ncode') -- lasttarget -- 'pc' of last 'jump target' -- jpc -- list of pending jumps to 'pc' -- freereg -- first free register -- nk -- number of elements in 'k' -- np -- number of elements in 'p' -- nlocvars -- number of elements in 'locvars' -- nactvar -- number of active local variables -- upvalues[LUAI_MAXUPVALUES] -- upvalues (table: upvaldesc) -- actvar[LUAI_MAXVARS] -- declared-variable stack ----------------------------------------------------------------------]] ------------------------------------------------------------------------ -- constants used by parser -- * picks up duplicate values from luaX if required ------------------------------------------------------------------------ luaY.LUA_QS = luaX.LUA_QS or "'%s'" -- (from luaconf.h) luaY.SHRT_MAX = 32767 -- (from ) luaY.LUAI_MAXVARS = 200 -- (luaconf.h) luaY.LUAI_MAXUPVALUES = 60 -- (luaconf.h) luaY.MAX_INT = luaX.MAX_INT or 2147483645 -- (from llimits.h) -- * INT_MAX-2 for 32-bit systems luaY.LUAI_MAXCCALLS = 200 -- (from luaconf.h) luaY.VARARG_HASARG = 1 -- (from lobject.h) -- NOTE: HASARG_MASK is value-specific luaY.HASARG_MASK = 2 -- this was added for a bitop in parlist() luaY.VARARG_ISVARARG = 2 -- NOTE: there is some value-specific code that involves VARARG_NEEDSARG luaY.VARARG_NEEDSARG = 4 luaY.LUA_MULTRET = -1 -- (lua.h) --[[-------------------------------------------------------------------- -- other functions ----------------------------------------------------------------------]] ------------------------------------------------------------------------ -- LUA_QL describes how error messages quote program elements. -- CHANGE it if you want a different appearance. (from luaconf.h) ------------------------------------------------------------------------ function luaY:LUA_QL(x) return "'"..x.."'" end ------------------------------------------------------------------------ -- this is a stripped-down luaM_growvector (from lmem.h) which is a -- macro based on luaM_growaux (in lmem.c); all the following does is -- reproduce the size limit checking logic of the original function -- so that error behaviour is identical; all arguments preserved for -- convenience, even those which are unused -- * set the t field to nil, since this originally does a sizeof(t) -- * size (originally a pointer) is never updated, their final values -- are set by luaY:close_func(), so overall things should still work ------------------------------------------------------------------------ function luaY:growvector(L, v, nelems, size, t, limit, e) if nelems >= limit then error(e) -- was luaG_runerror end end ------------------------------------------------------------------------ -- initialize a new function prototype structure (from lfunc.c) -- * used only in open_func() ------------------------------------------------------------------------ function luaY:newproto(L) local f = {} -- Proto -- luaC_link(L, obj2gco(f), LUA_TPROTO); /* GC */ f.k = {} f.sizek = 0 f.p = {} f.sizep = 0 f.code = {} f.sizecode = 0 f.sizelineinfo = 0 f.sizeupvalues = 0 f.nups = 0 f.upvalues = {} f.numparams = 0 f.is_vararg = 0 f.maxstacksize = 0 f.lineinfo = {} f.sizelocvars = 0 f.locvars = {} f.lineDefined = 0 f.lastlinedefined = 0 f.source = nil return f end ------------------------------------------------------------------------ -- converts an integer to a "floating point byte", represented as -- (eeeeexxx), where the real value is (1xxx) * 2^(eeeee - 1) if -- eeeee != 0 and (xxx) otherwise. ------------------------------------------------------------------------ function luaY:int2fb(x) local e = 0 -- exponent while x >= 16 do x = math.floor((x + 1) / 2) e = e + 1 end if x < 8 then return x else return ((e + 1) * 8) + (x - 8) end end --[[-------------------------------------------------------------------- -- parser functions ----------------------------------------------------------------------]] ------------------------------------------------------------------------ -- true of the kind of expression produces multiple return values ------------------------------------------------------------------------ function luaY:hasmultret(k) return k == "VCALL" or k == "VVARARG" end ------------------------------------------------------------------------ -- convenience function to access active local i, returns entry ------------------------------------------------------------------------ function luaY:getlocvar(fs, i) return fs.f.locvars[ fs.actvar[i] ] end ------------------------------------------------------------------------ -- check a limit, string m provided as an error message ------------------------------------------------------------------------ function luaY:checklimit(fs, v, l, m) if v > l then self:errorlimit(fs, l, m) end end --[[-------------------------------------------------------------------- -- nodes for block list (list of active blocks) -- struct BlockCnt: -- previous -- chain (table: BlockCnt) -- breaklist -- list of jumps out of this loop -- nactvar -- # active local variables outside the breakable structure -- upval -- true if some variable in the block is an upvalue (boolean) -- isbreakable -- true if 'block' is a loop (boolean) ----------------------------------------------------------------------]] ------------------------------------------------------------------------ -- prototypes for recursive non-terminal functions ------------------------------------------------------------------------ -- prototypes deleted; not required in Lua ------------------------------------------------------------------------ -- reanchor if last token is has a constant string, see close_func() -- * used only in close_func() ------------------------------------------------------------------------ function luaY:anchor_token(ls) if ls.t.token == "TK_NAME" or ls.t.token == "TK_STRING" then -- not relevant to Lua implementation of parser -- local ts = ls.t.seminfo -- luaX_newstring(ls, getstr(ts), ts->tsv.len); /* C */ end end ------------------------------------------------------------------------ -- throws a syntax error if token expected is not there ------------------------------------------------------------------------ function luaY:error_expected(ls, token) luaX:syntaxerror(ls, string.format(self.LUA_QS.." expected", luaX:token2str(ls, token))) end ------------------------------------------------------------------------ -- prepares error message for display, for limits exceeded -- * used only in checklimit() ------------------------------------------------------------------------ function luaY:errorlimit(fs, limit, what) local msg = (fs.f.linedefined == 0) and string.format("main function has more than %d %s", limit, what) or string.format("function at line %d has more than %d %s", fs.f.linedefined, limit, what) luaX:lexerror(fs.ls, msg, 0) end ------------------------------------------------------------------------ -- tests for a token, returns outcome -- * return value changed to boolean ------------------------------------------------------------------------ function luaY:testnext(ls, c) if ls.t.token == c then luaX:next(ls) return true else return false end end ------------------------------------------------------------------------ -- check for existence of a token, throws error if not found ------------------------------------------------------------------------ function luaY:check(ls, c) if ls.t.token ~= c then self:error_expected(ls, c) end end ------------------------------------------------------------------------ -- verify existence of a token, then skip it ------------------------------------------------------------------------ function luaY:checknext(ls, c) self:check(ls, c) luaX:next(ls) end ------------------------------------------------------------------------ -- throws error if condition not matched ------------------------------------------------------------------------ function luaY:check_condition(ls, c, msg) if not c then luaX:syntaxerror(ls, msg) end end ------------------------------------------------------------------------ -- verifies token conditions are met or else throw error ------------------------------------------------------------------------ function luaY:check_match(ls, what, who, where) if not self:testnext(ls, what) then if where == ls.linenumber then self:error_expected(ls, what) else luaX:syntaxerror(ls, string.format( self.LUA_QS.." expected (to close "..self.LUA_QS.." at line %d)", luaX:token2str(ls, what), luaX:token2str(ls, who), where)) end end end ------------------------------------------------------------------------ -- expect that token is a name, return the name ------------------------------------------------------------------------ function luaY:str_checkname(ls) self:check(ls, "TK_NAME") local ts = ls.t.seminfo luaX:next(ls) return ts end ------------------------------------------------------------------------ -- initialize a struct expdesc, expression description data structure ------------------------------------------------------------------------ function luaY:init_exp(e, k, i) e.f, e.t = luaK.NO_JUMP, luaK.NO_JUMP e.k = k e.info = i end ------------------------------------------------------------------------ -- adds given string s in string pool, sets e as VK ------------------------------------------------------------------------ function luaY:codestring(ls, e, s) self:init_exp(e, "VK", luaK:stringK(ls.fs, s)) end ------------------------------------------------------------------------ -- consume a name token, adds it to string pool, sets e as VK ------------------------------------------------------------------------ function luaY:checkname(ls, e) self:codestring(ls, e, self:str_checkname(ls)) end ------------------------------------------------------------------------ -- creates struct entry for a local variable -- * used only in new_localvar() ------------------------------------------------------------------------ function luaY:registerlocalvar(ls, varname) local fs = ls.fs local f = fs.f self:growvector(ls.L, f.locvars, fs.nlocvars, f.sizelocvars, nil, self.SHRT_MAX, "too many local variables") -- loop to initialize empty f.locvar positions not required f.locvars[fs.nlocvars] = {} -- LocVar f.locvars[fs.nlocvars].varname = varname -- luaC_objbarrier(ls.L, f, varname) /* GC */ local nlocvars = fs.nlocvars fs.nlocvars = fs.nlocvars + 1 return nlocvars end ------------------------------------------------------------------------ -- creates a new local variable given a name and an offset from nactvar -- * used in fornum(), forlist(), parlist(), body() ------------------------------------------------------------------------ function luaY:new_localvarliteral(ls, v, n) self:new_localvar(ls, v, n) end ------------------------------------------------------------------------ -- register a local variable, set in active variable list ------------------------------------------------------------------------ function luaY:new_localvar(ls, name, n) local fs = ls.fs self:checklimit(fs, fs.nactvar + n + 1, self.LUAI_MAXVARS, "local variables") fs.actvar[fs.nactvar + n] = self:registerlocalvar(ls, name) end ------------------------------------------------------------------------ -- adds nvars number of new local variables, set debug information ------------------------------------------------------------------------ function luaY:adjustlocalvars(ls, nvars) local fs = ls.fs fs.nactvar = fs.nactvar + nvars for i = nvars, 1, -1 do self:getlocvar(fs, fs.nactvar - i).startpc = fs.pc end end ------------------------------------------------------------------------ -- removes a number of locals, set debug information ------------------------------------------------------------------------ function luaY:removevars(ls, tolevel) local fs = ls.fs while fs.nactvar > tolevel do fs.nactvar = fs.nactvar - 1 self:getlocvar(fs, fs.nactvar).endpc = fs.pc end end ------------------------------------------------------------------------ -- returns an existing upvalue index based on the given name, or -- creates a new upvalue struct entry and returns the new index -- * used only in singlevaraux() ------------------------------------------------------------------------ function luaY:indexupvalue(fs, name, v) local f = fs.f for i = 0, f.nups - 1 do if fs.upvalues[i].k == v.k and fs.upvalues[i].info == v.info then lua_assert(f.upvalues[i] == name) return i end end -- new one self:checklimit(fs, f.nups + 1, self.LUAI_MAXUPVALUES, "upvalues") self:growvector(fs.L, f.upvalues, f.nups, f.sizeupvalues, nil, self.MAX_INT, "") -- loop to initialize empty f.upvalues positions not required f.upvalues[f.nups] = name -- luaC_objbarrier(fs->L, f, name); /* GC */ lua_assert(v.k == "VLOCAL" or v.k == "VUPVAL") -- this is a partial copy; only k & info fields used fs.upvalues[f.nups] = { k = v.k, info = v.info } local nups = f.nups f.nups = f.nups + 1 return nups end ------------------------------------------------------------------------ -- search the local variable namespace of the given fs for a match -- * used only in singlevaraux() ------------------------------------------------------------------------ function luaY:searchvar(fs, n) for i = fs.nactvar - 1, 0, -1 do if n == self:getlocvar(fs, i).varname then return i end end return -1 -- not found end ------------------------------------------------------------------------ -- * mark upvalue flags in function states up to a given level -- * used only in singlevaraux() ------------------------------------------------------------------------ function luaY:markupval(fs, level) local bl = fs.bl while bl and bl.nactvar > level do bl = bl.previous end if bl then bl.upval = true end end ------------------------------------------------------------------------ -- handle locals, globals and upvalues and related processing -- * search mechanism is recursive, calls itself to search parents -- * used only in singlevar() ------------------------------------------------------------------------ function luaY:singlevaraux(fs, n, var, base) if fs == nil then -- no more levels? self:init_exp(var, "VGLOBAL", luaP.NO_REG) -- default is global variable return "VGLOBAL" else local v = self:searchvar(fs, n) -- look up at current level if v >= 0 then self:init_exp(var, "VLOCAL", v) if base == 0 then self:markupval(fs, v) -- local will be used as an upval end return "VLOCAL" else -- not found at current level; try upper one if self:singlevaraux(fs.prev, n, var, 0) == "VGLOBAL" then return "VGLOBAL" end var.info = self:indexupvalue(fs, n, var) -- else was LOCAL or UPVAL var.k = "VUPVAL" -- upvalue in this level return "VUPVAL" end--if v end--if fs end ------------------------------------------------------------------------ -- consume a name token, creates a variable (global|local|upvalue) -- * used in prefixexp(), funcname() ------------------------------------------------------------------------ function luaY:singlevar(ls, var) local varname = self:str_checkname(ls) local fs = ls.fs if self:singlevaraux(fs, varname, var, 1) == "VGLOBAL" then var.info = luaK:stringK(fs, varname) -- info points to global name end end ------------------------------------------------------------------------ -- adjust RHS to match LHS in an assignment -- * used in assignment(), forlist(), localstat() ------------------------------------------------------------------------ function luaY:adjust_assign(ls, nvars, nexps, e) local fs = ls.fs local extra = nvars - nexps if self:hasmultret(e.k) then extra = extra + 1 -- includes call itself if extra <= 0 then extra = 0 end luaK:setreturns(fs, e, extra) -- last exp. provides the difference if extra > 1 then luaK:reserveregs(fs, extra - 1) end else if e.k ~= "VVOID" then luaK:exp2nextreg(fs, e) end -- close last expression if extra > 0 then local reg = fs.freereg luaK:reserveregs(fs, extra) luaK:_nil(fs, reg, extra) end end end ------------------------------------------------------------------------ -- tracks and limits parsing depth, assert check at end of parsing ------------------------------------------------------------------------ function luaY:enterlevel(ls) ls.L.nCcalls = ls.L.nCcalls + 1 if ls.L.nCcalls > self.LUAI_MAXCCALLS then luaX:lexerror(ls, "chunk has too many syntax levels", 0) end end ------------------------------------------------------------------------ -- tracks parsing depth, a pair with luaY:enterlevel() ------------------------------------------------------------------------ function luaY:leavelevel(ls) ls.L.nCcalls = ls.L.nCcalls - 1 end ------------------------------------------------------------------------ -- enters a code unit, initializes elements ------------------------------------------------------------------------ function luaY:enterblock(fs, bl, isbreakable) bl.breaklist = luaK.NO_JUMP bl.isbreakable = isbreakable bl.nactvar = fs.nactvar bl.upval = false bl.previous = fs.bl fs.bl = bl lua_assert(fs.freereg == fs.nactvar) end ------------------------------------------------------------------------ -- leaves a code unit, close any upvalues ------------------------------------------------------------------------ function luaY:leaveblock(fs) local bl = fs.bl fs.bl = bl.previous self:removevars(fs.ls, bl.nactvar) if bl.upval then luaK:codeABC(fs, "OP_CLOSE", bl.nactvar, 0, 0) end -- a block either controls scope or breaks (never both) lua_assert(not bl.isbreakable or not bl.upval) lua_assert(bl.nactvar == fs.nactvar) fs.freereg = fs.nactvar -- free registers luaK:patchtohere(fs, bl.breaklist) end ------------------------------------------------------------------------ -- implement the instantiation of a function prototype, append list of -- upvalues after the instantiation instruction -- * used only in body() ------------------------------------------------------------------------ function luaY:pushclosure(ls, func, v) local fs = ls.fs local f = fs.f self:growvector(ls.L, f.p, fs.np, f.sizep, nil, luaP.MAXARG_Bx, "constant table overflow") -- loop to initialize empty f.p positions not required f.p[fs.np] = func.f fs.np = fs.np + 1 -- luaC_objbarrier(ls->L, f, func->f); /* C */ self:init_exp(v, "VRELOCABLE", luaK:codeABx(fs, "OP_CLOSURE", 0, fs.np - 1)) for i = 0, func.f.nups - 1 do local o = (func.upvalues[i].k == "VLOCAL") and "OP_MOVE" or "OP_GETUPVAL" luaK:codeABC(fs, o, 0, func.upvalues[i].info, 0) end end ------------------------------------------------------------------------ -- opening of a function ------------------------------------------------------------------------ function luaY:open_func(ls, fs) local L = ls.L local f = self:newproto(ls.L) fs.f = f fs.prev = ls.fs -- linked list of funcstates fs.ls = ls fs.L = L ls.fs = fs fs.pc = 0 fs.lasttarget = -1 fs.jpc = luaK.NO_JUMP fs.freereg = 0 fs.nk = 0 fs.np = 0 fs.nlocvars = 0 fs.nactvar = 0 fs.bl = nil f.source = ls.source f.maxstacksize = 2 -- registers 0/1 are always valid fs.h = {} -- constant table; was luaH_new call -- anchor table of constants and prototype (to avoid being collected) -- sethvalue2s(L, L->top, fs->h); incr_top(L); /* C */ -- setptvalue2s(L, L->top, f); incr_top(L); end ------------------------------------------------------------------------ -- closing of a function ------------------------------------------------------------------------ function luaY:close_func(ls) local L = ls.L local fs = ls.fs local f = fs.f self:removevars(ls, 0) luaK:ret(fs, 0, 0) -- final return -- luaM_reallocvector deleted for f->code, f->lineinfo, f->k, f->p, -- f->locvars, f->upvalues; not required for Lua table arrays f.sizecode = fs.pc f.sizelineinfo = fs.pc f.sizek = fs.nk f.sizep = fs.np f.sizelocvars = fs.nlocvars f.sizeupvalues = f.nups --lua_assert(luaG_checkcode(f)) -- currently not implemented lua_assert(fs.bl == nil) ls.fs = fs.prev -- the following is not required for this implementation; kept here -- for completeness -- L->top -= 2; /* remove table and prototype from the stack */ -- last token read was anchored in defunct function; must reanchor it if fs then self:anchor_token(ls) end end ------------------------------------------------------------------------ -- parser initialization function -- * note additional sub-tables needed for LexState, FuncState ------------------------------------------------------------------------ function luaY:parser(L, z, buff, name) local lexstate = {} -- LexState lexstate.t = {} lexstate.lookahead = {} local funcstate = {} -- FuncState funcstate.upvalues = {} funcstate.actvar = {} -- the following nCcalls initialization added for convenience L.nCcalls = 0 lexstate.buff = buff luaX:setinput(L, lexstate, z, name) self:open_func(lexstate, funcstate) funcstate.f.is_vararg = self.VARARG_ISVARARG -- main func. is always vararg luaX:next(lexstate) -- read first token self:chunk(lexstate) self:check(lexstate, "TK_EOS") self:close_func(lexstate) lua_assert(funcstate.prev == nil) lua_assert(funcstate.f.nups == 0) lua_assert(lexstate.fs == nil) return funcstate.f end --[[-------------------------------------------------------------------- -- GRAMMAR RULES ----------------------------------------------------------------------]] ------------------------------------------------------------------------ -- parse a function name suffix, for function call specifications -- * used in primaryexp(), funcname() ------------------------------------------------------------------------ function luaY:field(ls, v) -- field -> ['.' | ':'] NAME local fs = ls.fs local key = {} -- expdesc luaK:exp2anyreg(fs, v) luaX:next(ls) -- skip the dot or colon self:checkname(ls, key) luaK:indexed(fs, v, key) end ------------------------------------------------------------------------ -- parse a table indexing suffix, for constructors, expressions -- * used in recfield(), primaryexp() ------------------------------------------------------------------------ function luaY:yindex(ls, v) -- index -> '[' expr ']' luaX:next(ls) -- skip the '[' self:expr(ls, v) luaK:exp2val(ls.fs, v) self:checknext(ls, "]") end --[[-------------------------------------------------------------------- -- Rules for Constructors ----------------------------------------------------------------------]] --[[-------------------------------------------------------------------- -- struct ConsControl: -- v -- last list item read (table: struct expdesc) -- t -- table descriptor (table: struct expdesc) -- nh -- total number of 'record' elements -- na -- total number of array elements -- tostore -- number of array elements pending to be stored ----------------------------------------------------------------------]] ------------------------------------------------------------------------ -- parse a table record (hash) field -- * used in constructor() ------------------------------------------------------------------------ function luaY:recfield(ls, cc) -- recfield -> (NAME | '['exp1']') = exp1 local fs = ls.fs local reg = ls.fs.freereg local key, val = {}, {} -- expdesc if ls.t.token == "TK_NAME" then self:checklimit(fs, cc.nh, self.MAX_INT, "items in a constructor") self:checkname(ls, key) else -- ls->t.token == '[' self:yindex(ls, key) end cc.nh = cc.nh + 1 self:checknext(ls, "=") local rkkey = luaK:exp2RK(fs, key) self:expr(ls, val) luaK:codeABC(fs, "OP_SETTABLE", cc.t.info, rkkey, luaK:exp2RK(fs, val)) fs.freereg = reg -- free registers end ------------------------------------------------------------------------ -- emit a set list instruction if enough elements (LFIELDS_PER_FLUSH) -- * used in constructor() ------------------------------------------------------------------------ function luaY:closelistfield(fs, cc) if cc.v.k == "VVOID" then return end -- there is no list item luaK:exp2nextreg(fs, cc.v) cc.v.k = "VVOID" if cc.tostore == luaP.LFIELDS_PER_FLUSH then luaK:setlist(fs, cc.t.info, cc.na, cc.tostore) -- flush cc.tostore = 0 -- no more items pending end end ------------------------------------------------------------------------ -- emit a set list instruction at the end of parsing list constructor -- * used in constructor() ------------------------------------------------------------------------ function luaY:lastlistfield(fs, cc) if cc.tostore == 0 then return end if self:hasmultret(cc.v.k) then luaK:setmultret(fs, cc.v) luaK:setlist(fs, cc.t.info, cc.na, self.LUA_MULTRET) cc.na = cc.na - 1 -- do not count last expression (unknown number of elements) else if cc.v.k ~= "VVOID" then luaK:exp2nextreg(fs, cc.v) end luaK:setlist(fs, cc.t.info, cc.na, cc.tostore) end end ------------------------------------------------------------------------ -- parse a table list (array) field -- * used in constructor() ------------------------------------------------------------------------ function luaY:listfield(ls, cc) self:expr(ls, cc.v) self:checklimit(ls.fs, cc.na, self.MAX_INT, "items in a constructor") cc.na = cc.na + 1 cc.tostore = cc.tostore + 1 end ------------------------------------------------------------------------ -- parse a table constructor -- * used in funcargs(), simpleexp() ------------------------------------------------------------------------ function luaY:constructor(ls, t) -- constructor -> '{' [ field { fieldsep field } [ fieldsep ] ] '}' -- field -> recfield | listfield -- fieldsep -> ',' | ';' local fs = ls.fs local line = ls.linenumber local pc = luaK:codeABC(fs, "OP_NEWTABLE", 0, 0, 0) local cc = {} -- ConsControl cc.v = {} cc.na, cc.nh, cc.tostore = 0, 0, 0 cc.t = t self:init_exp(t, "VRELOCABLE", pc) self:init_exp(cc.v, "VVOID", 0) -- no value (yet) luaK:exp2nextreg(ls.fs, t) -- fix it at stack top (for gc) self:checknext(ls, "{") repeat lua_assert(cc.v.k == "VVOID" or cc.tostore > 0) if ls.t.token == "}" then break end self:closelistfield(fs, cc) local c = ls.t.token if c == "TK_NAME" then -- may be listfields or recfields luaX:lookahead(ls) if ls.lookahead.token ~= "=" then -- expression? self:listfield(ls, cc) else self:recfield(ls, cc) end elseif c == "[" then -- constructor_item -> recfield self:recfield(ls, cc) else -- constructor_part -> listfield self:listfield(ls, cc) end until not self:testnext(ls, ",") and not self:testnext(ls, ";") self:check_match(ls, "}", "{", line) self:lastlistfield(fs, cc) luaP:SETARG_B(fs.f.code[pc], self:int2fb(cc.na)) -- set initial array size luaP:SETARG_C(fs.f.code[pc], self:int2fb(cc.nh)) -- set initial table size end -- }====================================================================== ------------------------------------------------------------------------ -- parse the arguments (parameters) of a function declaration -- * used in body() ------------------------------------------------------------------------ function luaY:parlist(ls) -- parlist -> [ param { ',' param } ] local fs = ls.fs local f = fs.f local nparams = 0 f.is_vararg = 0 if ls.t.token ~= ")" then -- is 'parlist' not empty? repeat local c = ls.t.token if c == "TK_NAME" then -- param -> NAME self:new_localvar(ls, self:str_checkname(ls), nparams) nparams = nparams + 1 elseif c == "TK_DOTS" then -- param -> `...' luaX:next(ls) -- [[ -- #if defined(LUA_COMPAT_VARARG) -- use `arg' as default name self:new_localvarliteral(ls, "arg", nparams) nparams = nparams + 1 f.is_vararg = self.VARARG_HASARG + self.VARARG_NEEDSARG -- #endif --]] f.is_vararg = f.is_vararg + self.VARARG_ISVARARG else luaX:syntaxerror(ls, " or "..self:LUA_QL("...").." expected") end until f.is_vararg ~= 0 or not self:testnext(ls, ",") end--if self:adjustlocalvars(ls, nparams) -- NOTE: the following works only when HASARG_MASK is 2! f.numparams = fs.nactvar - (f.is_vararg % self.HASARG_MASK) luaK:reserveregs(fs, fs.nactvar) -- reserve register for parameters end ------------------------------------------------------------------------ -- parse function declaration body -- * used in simpleexp(), localfunc(), funcstat() ------------------------------------------------------------------------ function luaY:body(ls, e, needself, line) -- body -> '(' parlist ')' chunk END local new_fs = {} -- FuncState new_fs.upvalues = {} new_fs.actvar = {} self:open_func(ls, new_fs) new_fs.f.lineDefined = line self:checknext(ls, "(") if needself then self:new_localvarliteral(ls, "self", 0) self:adjustlocalvars(ls, 1) end self:parlist(ls) self:checknext(ls, ")") self:chunk(ls) new_fs.f.lastlinedefined = ls.linenumber self:check_match(ls, "TK_END", "TK_FUNCTION", line) self:close_func(ls) self:pushclosure(ls, new_fs, e) end ------------------------------------------------------------------------ -- parse a list of comma-separated expressions -- * used is multiple locations ------------------------------------------------------------------------ function luaY:explist1(ls, v) -- explist1 -> expr { ',' expr } local n = 1 -- at least one expression self:expr(ls, v) while self:testnext(ls, ",") do luaK:exp2nextreg(ls.fs, v) self:expr(ls, v) n = n + 1 end return n end ------------------------------------------------------------------------ -- parse the parameters of a function call -- * contrast with parlist(), used in function declarations -- * used in primaryexp() ------------------------------------------------------------------------ function luaY:funcargs(ls, f) local fs = ls.fs local args = {} -- expdesc local nparams local line = ls.linenumber local c = ls.t.token if c == "(" then -- funcargs -> '(' [ explist1 ] ')' if line ~= ls.lastline then luaX:syntaxerror(ls, "ambiguous syntax (function call x new statement)") end luaX:next(ls) if ls.t.token == ")" then -- arg list is empty? args.k = "VVOID" else self:explist1(ls, args) luaK:setmultret(fs, args) end self:check_match(ls, ")", "(", line) elseif c == "{" then -- funcargs -> constructor self:constructor(ls, args) elseif c == "TK_STRING" then -- funcargs -> STRING self:codestring(ls, args, ls.t.seminfo) luaX:next(ls) -- must use 'seminfo' before 'next' else luaX:syntaxerror(ls, "function arguments expected") return end lua_assert(f.k == "VNONRELOC") local base = f.info -- base register for call if self:hasmultret(args.k) then nparams = self.LUA_MULTRET -- open call else if args.k ~= "VVOID" then luaK:exp2nextreg(fs, args) -- close last argument end nparams = fs.freereg - (base + 1) end self:init_exp(f, "VCALL", luaK:codeABC(fs, "OP_CALL", base, nparams + 1, 2)) luaK:fixline(fs, line) fs.freereg = base + 1 -- call remove function and arguments and leaves -- (unless changed) one result end --[[-------------------------------------------------------------------- -- Expression parsing ----------------------------------------------------------------------]] ------------------------------------------------------------------------ -- parses an expression in parentheses or a single variable -- * used in primaryexp() ------------------------------------------------------------------------ function luaY:prefixexp(ls, v) -- prefixexp -> NAME | '(' expr ')' local c = ls.t.token if c == "(" then local line = ls.linenumber luaX:next(ls) self:expr(ls, v) self:check_match(ls, ")", "(", line) luaK:dischargevars(ls.fs, v) elseif c == "TK_NAME" then self:singlevar(ls, v) else luaX:syntaxerror(ls, "unexpected symbol") end--if c return end ------------------------------------------------------------------------ -- parses a prefixexp (an expression in parentheses or a single variable) -- or a function call specification -- * used in simpleexp(), assignment(), exprstat() ------------------------------------------------------------------------ function luaY:primaryexp(ls, v) -- primaryexp -> -- prefixexp { '.' NAME | '[' exp ']' | ':' NAME funcargs | funcargs } local fs = ls.fs self:prefixexp(ls, v) while true do local c = ls.t.token if c == "." then -- field self:field(ls, v) elseif c == "[" then -- '[' exp1 ']' local key = {} -- expdesc luaK:exp2anyreg(fs, v) self:yindex(ls, key) luaK:indexed(fs, v, key) elseif c == ":" then -- ':' NAME funcargs local key = {} -- expdesc luaX:next(ls) self:checkname(ls, key) luaK:_self(fs, v, key) self:funcargs(ls, v) elseif c == "(" or c == "TK_STRING" or c == "{" then -- funcargs luaK:exp2nextreg(fs, v) self:funcargs(ls, v) else return end--if c end--while end ------------------------------------------------------------------------ -- parses general expression types, constants handled here -- * used in subexpr() ------------------------------------------------------------------------ function luaY:simpleexp(ls, v) -- simpleexp -> NUMBER | STRING | NIL | TRUE | FALSE | ... | -- constructor | FUNCTION body | primaryexp local c = ls.t.token if c == "TK_NUMBER" then self:init_exp(v, "VKNUM", 0) v.nval = ls.t.seminfo elseif c == "TK_STRING" then self:codestring(ls, v, ls.t.seminfo) elseif c == "TK_NIL" then self:init_exp(v, "VNIL", 0) elseif c == "TK_TRUE" then self:init_exp(v, "VTRUE", 0) elseif c == "TK_FALSE" then self:init_exp(v, "VFALSE", 0) elseif c == "TK_DOTS" then -- vararg local fs = ls.fs self:check_condition(ls, fs.f.is_vararg ~= 0, "cannot use "..self:LUA_QL("...").." outside a vararg function"); -- NOTE: the following substitutes for a bitop, but is value-specific local is_vararg = fs.f.is_vararg if is_vararg >= self.VARARG_NEEDSARG then fs.f.is_vararg = is_vararg - self.VARARG_NEEDSARG -- don't need 'arg' end self:init_exp(v, "VVARARG", luaK:codeABC(fs, "OP_VARARG", 0, 1, 0)) elseif c == "{" then -- constructor self:constructor(ls, v) return elseif c == "TK_FUNCTION" then luaX:next(ls) self:body(ls, v, false, ls.linenumber) return else self:primaryexp(ls, v) return end--if c luaX:next(ls) end ------------------------------------------------------------------------ -- Translates unary operators tokens if found, otherwise returns -- OPR_NOUNOPR. getunopr() and getbinopr() are used in subexpr(). -- * used in subexpr() ------------------------------------------------------------------------ function luaY:getunopr(op) if op == "TK_NOT" then return "OPR_NOT" elseif op == "-" then return "OPR_MINUS" elseif op == "#" then return "OPR_LEN" else return "OPR_NOUNOPR" end end ------------------------------------------------------------------------ -- Translates binary operator tokens if found, otherwise returns -- OPR_NOBINOPR. Code generation uses OPR_* style tokens. -- * used in subexpr() ------------------------------------------------------------------------ luaY.getbinopr_table = { ["+"] = "OPR_ADD", ["-"] = "OPR_SUB", ["*"] = "OPR_MUL", ["/"] = "OPR_DIV", ["%"] = "OPR_MOD", ["^"] = "OPR_POW", ["TK_CONCAT"] = "OPR_CONCAT", ["TK_NE"] = "OPR_NE", ["TK_EQ"] = "OPR_EQ", ["<"] = "OPR_LT", ["TK_LE"] = "OPR_LE", [">"] = "OPR_GT", ["TK_GE"] = "OPR_GE", ["TK_AND"] = "OPR_AND", ["TK_OR"] = "OPR_OR", } function luaY:getbinopr(op) local opr = self.getbinopr_table[op] if opr then return opr else return "OPR_NOBINOPR" end end ------------------------------------------------------------------------ -- the following priority table consists of pairs of left/right values -- for binary operators (was a static const struct); grep for ORDER OPR -- * the following struct is replaced: -- static const struct { -- lu_byte left; /* left priority for each binary operator */ -- lu_byte right; /* right priority */ -- } priority[] = { /* ORDER OPR */ ------------------------------------------------------------------------ luaY.priority = { {6, 6}, {6, 6}, {7, 7}, {7, 7}, {7, 7}, -- `+' `-' `/' `%' {10, 9}, {5, 4}, -- power and concat (right associative) {3, 3}, {3, 3}, -- equality {3, 3}, {3, 3}, {3, 3}, {3, 3}, -- order {2, 2}, {1, 1} -- logical (and/or) } luaY.UNARY_PRIORITY = 8 -- priority for unary operators ------------------------------------------------------------------------ -- Parse subexpressions. Includes handling of unary operators and binary -- operators. A subexpr is given the rhs priority level of the operator -- immediately left of it, if any (limit is -1 if none,) and if a binop -- is found, limit is compared with the lhs priority level of the binop -- in order to determine which executes first. ------------------------------------------------------------------------ ------------------------------------------------------------------------ -- subexpr -> (simpleexp | unop subexpr) { binop subexpr } -- where 'binop' is any binary operator with a priority higher than 'limit' -- * for priority lookups with self.priority[], 1=left and 2=right -- * recursively called -- * used in expr() ------------------------------------------------------------------------ function luaY:subexpr(ls, v, limit) self:enterlevel(ls) local uop = self:getunopr(ls.t.token) if uop ~= "OPR_NOUNOPR" then luaX:next(ls) self:subexpr(ls, v, self.UNARY_PRIORITY) luaK:prefix(ls.fs, uop, v) else self:simpleexp(ls, v) end -- expand while operators have priorities higher than 'limit' local op = self:getbinopr(ls.t.token) while op ~= "OPR_NOBINOPR" and self.priority[luaK.BinOpr[op] + 1][1] > limit do local v2 = {} -- expdesc luaX:next(ls) luaK:infix(ls.fs, op, v) -- read sub-expression with higher priority local nextop = self:subexpr(ls, v2, self.priority[luaK.BinOpr[op] + 1][2]) luaK:posfix(ls.fs, op, v, v2) op = nextop end self:leavelevel(ls) return op -- return first untreated operator end ------------------------------------------------------------------------ -- Expression parsing starts here. Function subexpr is entered with the -- left operator (which is non-existent) priority of -1, which is lower -- than all actual operators. Expr information is returned in parm v. -- * used in multiple locations ------------------------------------------------------------------------ function luaY:expr(ls, v) self:subexpr(ls, v, 0) end -- }==================================================================== --[[-------------------------------------------------------------------- -- Rules for Statements ----------------------------------------------------------------------]] ------------------------------------------------------------------------ -- checks next token, used as a look-ahead -- * returns boolean instead of 0|1 -- * used in retstat(), chunk() ------------------------------------------------------------------------ function luaY:block_follow(token) if token == "TK_ELSE" or token == "TK_ELSEIF" or token == "TK_END" or token == "TK_UNTIL" or token == "TK_EOS" then return true else return false end end ------------------------------------------------------------------------ -- parse a code block or unit -- * used in multiple functions ------------------------------------------------------------------------ function luaY:block(ls) -- block -> chunk local fs = ls.fs local bl = {} -- BlockCnt self:enterblock(fs, bl, false) self:chunk(ls) lua_assert(bl.breaklist == luaK.NO_JUMP) self:leaveblock(fs) end ------------------------------------------------------------------------ -- structure to chain all variables in the left-hand side of an -- assignment -- struct LHS_assign: -- prev -- (table: struct LHS_assign) -- v -- variable (global, local, upvalue, or indexed) (table: expdesc) ------------------------------------------------------------------------ ------------------------------------------------------------------------ -- check whether, in an assignment to a local variable, the local variable -- is needed in a previous assignment (to a table). If so, save original -- local value in a safe place and use this safe copy in the previous -- assignment. -- * used in assignment() ------------------------------------------------------------------------ function luaY:check_conflict(ls, lh, v) local fs = ls.fs local extra = fs.freereg -- eventual position to save local variable local conflict = false while lh do if lh.v.k == "VINDEXED" then if lh.v.info == v.info then -- conflict? conflict = true lh.v.info = extra -- previous assignment will use safe copy end if lh.v.aux == v.info then -- conflict? conflict = true lh.v.aux = extra -- previous assignment will use safe copy end end lh = lh.prev end if conflict then luaK:codeABC(fs, "OP_MOVE", fs.freereg, v.info, 0) -- make copy luaK:reserveregs(fs, 1) end end ------------------------------------------------------------------------ -- parse a variable assignment sequence -- * recursively called -- * used in exprstat() ------------------------------------------------------------------------ function luaY:assignment(ls, lh, nvars) local e = {} -- expdesc -- test was: VLOCAL <= lh->v.k && lh->v.k <= VINDEXED local c = lh.v.k self:check_condition(ls, c == "VLOCAL" or c == "VUPVAL" or c == "VGLOBAL" or c == "VINDEXED", "syntax error") if self:testnext(ls, ",") then -- assignment -> ',' primaryexp assignment local nv = {} -- LHS_assign nv.v = {} nv.prev = lh self:primaryexp(ls, nv.v) if nv.v.k == "VLOCAL" then self:check_conflict(ls, lh, nv.v) end self:checklimit(ls.fs, nvars, self.LUAI_MAXCCALLS - ls.L.nCcalls, "variables in assignment") self:assignment(ls, nv, nvars + 1) else -- assignment -> '=' explist1 self:checknext(ls, "=") local nexps = self:explist1(ls, e) if nexps ~= nvars then self:adjust_assign(ls, nvars, nexps, e) if nexps > nvars then ls.fs.freereg = ls.fs.freereg - (nexps - nvars) -- remove extra values end else luaK:setoneret(ls.fs, e) -- close last expression luaK:storevar(ls.fs, lh.v, e) return -- avoid default end end self:init_exp(e, "VNONRELOC", ls.fs.freereg - 1) -- default assignment luaK:storevar(ls.fs, lh.v, e) end ------------------------------------------------------------------------ -- parse condition in a repeat statement or an if control structure -- * used in repeatstat(), test_then_block() ------------------------------------------------------------------------ function luaY:cond(ls) -- cond -> exp local v = {} -- expdesc self:expr(ls, v) -- read condition if v.k == "VNIL" then v.k = "VFALSE" end -- 'falses' are all equal here luaK:goiftrue(ls.fs, v) return v.f end ------------------------------------------------------------------------ -- parse a break statement -- * used in statements() ------------------------------------------------------------------------ function luaY:breakstat(ls) -- stat -> BREAK local fs = ls.fs local bl = fs.bl local upval = false while bl and not bl.isbreakable do if bl.upval then upval = true end bl = bl.previous end if not bl then luaX:syntaxerror(ls, "no loop to break") end if upval then luaK:codeABC(fs, "OP_CLOSE", bl.nactvar, 0, 0) end bl.breaklist = luaK:concat(fs, bl.breaklist, luaK:jump(fs)) end ------------------------------------------------------------------------ -- parse a while-do control structure, body processed by block() -- * with dynamic array sizes, MAXEXPWHILE + EXTRAEXP limits imposed by -- the function's implementation can be removed -- * used in statements() ------------------------------------------------------------------------ function luaY:whilestat(ls, line) -- whilestat -> WHILE cond DO block END local fs = ls.fs local bl = {} -- BlockCnt luaX:next(ls) -- skip WHILE local whileinit = luaK:getlabel(fs) local condexit = self:cond(ls) self:enterblock(fs, bl, true) self:checknext(ls, "TK_DO") self:block(ls) luaK:patchlist(fs, luaK:jump(fs), whileinit) self:check_match(ls, "TK_END", "TK_WHILE", line) self:leaveblock(fs) luaK:patchtohere(fs, condexit) -- false conditions finish the loop end ------------------------------------------------------------------------ -- parse a repeat-until control structure, body parsed by chunk() -- * used in statements() ------------------------------------------------------------------------ function luaY:repeatstat(ls, line) -- repeatstat -> REPEAT block UNTIL cond local fs = ls.fs local repeat_init = luaK:getlabel(fs) local bl1, bl2 = {}, {} -- BlockCnt self:enterblock(fs, bl1, true) -- loop block self:enterblock(fs, bl2, false) -- scope block luaX:next(ls) -- skip REPEAT self:chunk(ls) self:check_match(ls, "TK_UNTIL", "TK_REPEAT", line) local condexit = self:cond(ls) -- read condition (inside scope block) if not bl2.upval then -- no upvalues? self:leaveblock(fs) -- finish scope luaK:patchlist(ls.fs, condexit, repeat_init) -- close the loop else -- complete semantics when there are upvalues self:breakstat(ls) -- if condition then break luaK:patchtohere(ls.fs, condexit) -- else... self:leaveblock(fs) -- finish scope... luaK:patchlist(ls.fs, luaK:jump(fs), repeat_init) -- and repeat end self:leaveblock(fs) -- finish loop end ------------------------------------------------------------------------ -- parse the single expressions needed in numerical for loops -- * used in fornum() ------------------------------------------------------------------------ function luaY:exp1(ls) local e = {} -- expdesc self:expr(ls, e) local k = e.k luaK:exp2nextreg(ls.fs, e) return k end ------------------------------------------------------------------------ -- parse a for loop body for both versions of the for loop -- * used in fornum(), forlist() ------------------------------------------------------------------------ function luaY:forbody(ls, base, line, nvars, isnum) -- forbody -> DO block local bl = {} -- BlockCnt local fs = ls.fs self:adjustlocalvars(ls, 3) -- control variables self:checknext(ls, "TK_DO") local prep = isnum and luaK:codeAsBx(fs, "OP_FORPREP", base, luaK.NO_JUMP) or luaK:jump(fs) self:enterblock(fs, bl, false) -- scope for declared variables self:adjustlocalvars(ls, nvars) luaK:reserveregs(fs, nvars) self:block(ls) self:leaveblock(fs) -- end of scope for declared variables luaK:patchtohere(fs, prep) local endfor = isnum and luaK:codeAsBx(fs, "OP_FORLOOP", base, luaK.NO_JUMP) or luaK:codeABC(fs, "OP_TFORLOOP", base, 0, nvars) luaK:fixline(fs, line) -- pretend that `OP_FOR' starts the loop luaK:patchlist(fs, isnum and endfor or luaK:jump(fs), prep + 1) end ------------------------------------------------------------------------ -- parse a numerical for loop, calls forbody() -- * used in forstat() ------------------------------------------------------------------------ function luaY:fornum(ls, varname, line) -- fornum -> NAME = exp1,exp1[,exp1] forbody local fs = ls.fs local base = fs.freereg self:new_localvarliteral(ls, "(for index)", 0) self:new_localvarliteral(ls, "(for limit)", 1) self:new_localvarliteral(ls, "(for step)", 2) self:new_localvar(ls, varname, 3) self:checknext(ls, '=') self:exp1(ls) -- initial value self:checknext(ls, ",") self:exp1(ls) -- limit if self:testnext(ls, ",") then self:exp1(ls) -- optional step else -- default step = 1 luaK:codeABx(fs, "OP_LOADK", fs.freereg, luaK:numberK(fs, 1)) luaK:reserveregs(fs, 1) end self:forbody(ls, base, line, 1, true) end ------------------------------------------------------------------------ -- parse a generic for loop, calls forbody() -- * used in forstat() ------------------------------------------------------------------------ function luaY:forlist(ls, indexname) -- forlist -> NAME {,NAME} IN explist1 forbody local fs = ls.fs local e = {} -- expdesc local nvars = 0 local base = fs.freereg -- create control variables self:new_localvarliteral(ls, "(for generator)", nvars) nvars = nvars + 1 self:new_localvarliteral(ls, "(for state)", nvars) nvars = nvars + 1 self:new_localvarliteral(ls, "(for control)", nvars) nvars = nvars + 1 -- create declared variables self:new_localvar(ls, indexname, nvars) nvars = nvars + 1 while self:testnext(ls, ",") do self:new_localvar(ls, self:str_checkname(ls), nvars) nvars = nvars + 1 end self:checknext(ls, "TK_IN") local line = ls.linenumber self:adjust_assign(ls, 3, self:explist1(ls, e), e) luaK:checkstack(fs, 3) -- extra space to call generator self:forbody(ls, base, line, nvars - 3, false) end ------------------------------------------------------------------------ -- initial parsing for a for loop, calls fornum() or forlist() -- * used in statements() ------------------------------------------------------------------------ function luaY:forstat(ls, line) -- forstat -> FOR (fornum | forlist) END local fs = ls.fs local bl = {} -- BlockCnt self:enterblock(fs, bl, true) -- scope for loop and control variables luaX:next(ls) -- skip `for' local varname = self:str_checkname(ls) -- first variable name local c = ls.t.token if c == "=" then self:fornum(ls, varname, line) elseif c == "," or c == "TK_IN" then self:forlist(ls, varname) else luaX:syntaxerror(ls, self:LUA_QL("=").." or "..self:LUA_QL("in").." expected") end self:check_match(ls, "TK_END", "TK_FOR", line) self:leaveblock(fs) -- loop scope (`break' jumps to this point) end ------------------------------------------------------------------------ -- parse part of an if control structure, including the condition -- * used in ifstat() ------------------------------------------------------------------------ function luaY:test_then_block(ls) -- test_then_block -> [IF | ELSEIF] cond THEN block luaX:next(ls) -- skip IF or ELSEIF local condexit = self:cond(ls) self:checknext(ls, "TK_THEN") self:block(ls) -- `then' part return condexit end ------------------------------------------------------------------------ -- parse an if control structure -- * used in statements() ------------------------------------------------------------------------ function luaY:ifstat(ls, line) -- ifstat -> IF cond THEN block {ELSEIF cond THEN block} [ELSE block] END local fs = ls.fs local escapelist = luaK.NO_JUMP local flist = self:test_then_block(ls) -- IF cond THEN block while ls.t.token == "TK_ELSEIF" do escapelist = luaK:concat(fs, escapelist, luaK:jump(fs)) luaK:patchtohere(fs, flist) flist = self:test_then_block(ls) -- ELSEIF cond THEN block end if ls.t.token == "TK_ELSE" then escapelist = luaK:concat(fs, escapelist, luaK:jump(fs)) luaK:patchtohere(fs, flist) luaX:next(ls) -- skip ELSE (after patch, for correct line info) self:block(ls) -- 'else' part else escapelist = luaK:concat(fs, escapelist, flist) end luaK:patchtohere(fs, escapelist) self:check_match(ls, "TK_END", "TK_IF", line) end ------------------------------------------------------------------------ -- parse a local function statement -- * used in statements() ------------------------------------------------------------------------ function luaY:localfunc(ls) local v, b = {}, {} -- expdesc local fs = ls.fs self:new_localvar(ls, self:str_checkname(ls), 0) self:init_exp(v, "VLOCAL", fs.freereg) luaK:reserveregs(fs, 1) self:adjustlocalvars(ls, 1) self:body(ls, b, false, ls.linenumber) luaK:storevar(fs, v, b) -- debug information will only see the variable after this point! self:getlocvar(fs, fs.nactvar - 1).startpc = fs.pc end ------------------------------------------------------------------------ -- parse a local variable declaration statement -- * used in statements() ------------------------------------------------------------------------ function luaY:localstat(ls) -- stat -> LOCAL NAME {',' NAME} ['=' explist1] local nvars = 0 local nexps local e = {} -- expdesc repeat self:new_localvar(ls, self:str_checkname(ls), nvars) nvars = nvars + 1 until not self:testnext(ls, ",") if self:testnext(ls, "=") then nexps = self:explist1(ls, e) else e.k = "VVOID" nexps = 0 end self:adjust_assign(ls, nvars, nexps, e) self:adjustlocalvars(ls, nvars) end ------------------------------------------------------------------------ -- parse a function name specification -- * used in funcstat() ------------------------------------------------------------------------ function luaY:funcname(ls, v) -- funcname -> NAME {field} [':' NAME] local needself = false self:singlevar(ls, v) while ls.t.token == "." do self:field(ls, v) end if ls.t.token == ":" then needself = true self:field(ls, v) end return needself end ------------------------------------------------------------------------ -- parse a function statement -- * used in statements() ------------------------------------------------------------------------ function luaY:funcstat(ls, line) -- funcstat -> FUNCTION funcname body local v, b = {}, {} -- expdesc luaX:next(ls) -- skip FUNCTION local needself = self:funcname(ls, v) self:body(ls, b, needself, line) luaK:storevar(ls.fs, v, b) luaK:fixline(ls.fs, line) -- definition 'happens' in the first line end ------------------------------------------------------------------------ -- parse a function call with no returns or an assignment statement -- * used in statements() ------------------------------------------------------------------------ function luaY:exprstat(ls) -- stat -> func | assignment local fs = ls.fs local v = {} -- LHS_assign v.v = {} self:primaryexp(ls, v.v) if v.v.k == "VCALL" then -- stat -> func luaP:SETARG_C(luaK:getcode(fs, v.v), 1) -- call statement uses no results else -- stat -> assignment v.prev = nil self:assignment(ls, v, 1) end end ------------------------------------------------------------------------ -- parse a return statement -- * used in statements() ------------------------------------------------------------------------ function luaY:retstat(ls) -- stat -> RETURN explist local fs = ls.fs local e = {} -- expdesc local first, nret -- registers with returned values luaX:next(ls) -- skip RETURN if self:block_follow(ls.t.token) or ls.t.token == ";" then first, nret = 0, 0 -- return no values else nret = self:explist1(ls, e) -- optional return values if self:hasmultret(e.k) then luaK:setmultret(fs, e) if e.k == "VCALL" and nret == 1 then -- tail call? luaP:SET_OPCODE(luaK:getcode(fs, e), "OP_TAILCALL") lua_assert(luaP:GETARG_A(luaK:getcode(fs, e)) == fs.nactvar) end first = fs.nactvar nret = self.LUA_MULTRET -- return all values else if nret == 1 then -- only one single value? first = luaK:exp2anyreg(fs, e) else luaK:exp2nextreg(fs, e) -- values must go to the 'stack' first = fs.nactvar -- return all 'active' values lua_assert(nret == fs.freereg - first) end end--if end--if luaK:ret(fs, first, nret) end ------------------------------------------------------------------------ -- initial parsing for statements, calls a lot of functions -- * returns boolean instead of 0|1 -- * used in chunk() ------------------------------------------------------------------------ function luaY:statement(ls) local line = ls.linenumber -- may be needed for error messages local c = ls.t.token if c == "TK_IF" then -- stat -> ifstat self:ifstat(ls, line) return false elseif c == "TK_WHILE" then -- stat -> whilestat self:whilestat(ls, line) return false elseif c == "TK_DO" then -- stat -> DO block END luaX:next(ls) -- skip DO self:block(ls) self:check_match(ls, "TK_END", "TK_DO", line) return false elseif c == "TK_FOR" then -- stat -> forstat self:forstat(ls, line) return false elseif c == "TK_REPEAT" then -- stat -> repeatstat self:repeatstat(ls, line) return false elseif c == "TK_FUNCTION" then -- stat -> funcstat self:funcstat(ls, line) return false elseif c == "TK_LOCAL" then -- stat -> localstat luaX:next(ls) -- skip LOCAL if self:testnext(ls, "TK_FUNCTION") then -- local function? self:localfunc(ls) else self:localstat(ls) end return false elseif c == "TK_RETURN" then -- stat -> retstat self:retstat(ls) return true -- must be last statement elseif c == "TK_BREAK" then -- stat -> breakstat luaX:next(ls) -- skip BREAK self:breakstat(ls) return true -- must be last statement else self:exprstat(ls) return false -- to avoid warnings end--if c end ------------------------------------------------------------------------ -- parse a chunk, which consists of a bunch of statements -- * used in parser(), body(), block(), repeatstat() ------------------------------------------------------------------------ function luaY:chunk(ls) -- chunk -> { stat [';'] } local islast = false self:enterlevel(ls) while not islast and not self:block_follow(ls.t.token) do islast = self:statement(ls) self:testnext(ls, ";") lua_assert(ls.fs.f.maxstacksize >= ls.fs.freereg and ls.fs.freereg >= ls.fs.nactvar) ls.fs.freereg = ls.fs.nactvar -- free registers end self:leavelevel(ls) end -- }====================================================================== luaX:init() -- required by llex local LuaState = {} -- dummy, not actually used, but retained since -- the intention is to complete a straight port ------------------------------------------------------------------------ -- interfacing to yueliang ------------------------------------------------------------------------ local function compile(source, name) name = name or 'compiled-lua' -- luaZ:make_getF returns a file chunk reader -- luaZ:init returns a zio input stream local zio = luaZ:init(luaZ:make_getF(source), nil) if not zio then return end -- luaY:parser parses the input stream -- func is the function prototype in tabular form; in C, func can -- now be used directly by the VM, this can't be done in Lua local func = luaY:parser(LuaState, zio, nil, "@"..name) -- luaU:make_setS returns a string chunk writer local writer, buff = luaU:make_setS() -- luaU:dump builds a binary chunk luaU:dump(LuaState, func, writer, buff) -- a string.dump equivalent in returned return buff.data end if shine and shine.setCompiler then shine.setCompiler(compile) end end