diff options
Diffstat (limited to 'plugins/SmartAutoReplier/lualib/lparser.c')
| -rw-r--r-- | plugins/SmartAutoReplier/lualib/lparser.c | 1329 |
1 files changed, 0 insertions, 1329 deletions
diff --git a/plugins/SmartAutoReplier/lualib/lparser.c b/plugins/SmartAutoReplier/lualib/lparser.c deleted file mode 100644 index c1323ecd2a..0000000000 --- a/plugins/SmartAutoReplier/lualib/lparser.c +++ /dev/null @@ -1,1329 +0,0 @@ -/* -** $Id: lparser.c,v 1.208 2003/04/03 13:35:34 roberto Exp $ -** Lua Parser -** See Copyright Notice in lua.h -*/ - - -#include <string.h> - -#define lparser_c - -#include "lua.h" - -#include "lcode.h" -#include "ldebug.h" -#include "lfunc.h" -#include "llex.h" -#include "lmem.h" -#include "lobject.h" -#include "lopcodes.h" -#include "lparser.h" -#include "lstate.h" -#include "lstring.h" - - - - -#define getlocvar(fs, i) ((fs)->f->locvars[(fs)->actvar[i]]) - - -#define enterlevel(ls) if (++(ls)->nestlevel > LUA_MAXPARSERLEVEL) \ - luaX_syntaxerror(ls, "too many syntax levels"); -#define leavelevel(ls) ((ls)->nestlevel--) - - -/* -** nodes for block list (list of active blocks) -*/ -typedef struct BlockCnt { - struct BlockCnt *previous; /* chain */ - int breaklist; /* list of jumps out of this loop */ - int nactvar; /* # active local variables outside the breakable structure */ - int upval; /* true if some variable in the block is an upvalue */ - int isbreakable; /* true if `block' is a loop */ -} BlockCnt; - - - -/* -** prototypes for recursive non-terminal functions -*/ -static void chunk (LexState *ls); -static void expr (LexState *ls, expdesc *v); - - - -static void next (LexState *ls) { - ls->lastline = ls->linenumber; - if (ls->lookahead.token != TK_EOS) { /* is there a look-ahead token? */ - ls->t = ls->lookahead; /* use this one */ - ls->lookahead.token = TK_EOS; /* and discharge it */ - } - else - ls->t.token = luaX_lex(ls, &ls->t.seminfo); /* read next token */ -} - - -static void lookahead (LexState *ls) { - lua_assert(ls->lookahead.token == TK_EOS); - ls->lookahead.token = luaX_lex(ls, &ls->lookahead.seminfo); -} - - -static void error_expected (LexState *ls, int token) { - luaX_syntaxerror(ls, - luaO_pushfstring(ls->L, "`%s' expected", luaX_token2str(ls, token))); -} - - -static int testnext (LexState *ls, int c) { - if (ls->t.token == c) { - next(ls); - return 1; - } - else return 0; -} - - -static void check (LexState *ls, int c) { - if (!testnext(ls, c)) - error_expected(ls, c); -} - - -#define check_condition(ls,c,msg) { if (!(c)) luaX_syntaxerror(ls, msg); } - - - -static void check_match (LexState *ls, int what, int who, int where) { - if (!testnext(ls, what)) { - if (where == ls->linenumber) - error_expected(ls, what); - else { - luaX_syntaxerror(ls, luaO_pushfstring(ls->L, - "`%s' expected (to close `%s' at line %d)", - luaX_token2str(ls, what), luaX_token2str(ls, who), where)); - } - } -} - - -static TString *str_checkname (LexState *ls) { - TString *ts; - check_condition(ls, (ls->t.token == TK_NAME), "<name> expected"); - ts = ls->t.seminfo.ts; - next(ls); - return ts; -} - - -static void init_exp (expdesc *e, expkind k, int i) { - e->f = e->t = NO_JUMP; - e->k = k; - e->info = i; -} - - -static void codestring (LexState *ls, expdesc *e, TString *s) { - init_exp(e, VK, luaK_stringK(ls->fs, s)); -} - - -static void checkname(LexState *ls, expdesc *e) { - codestring(ls, e, str_checkname(ls)); -} - - -static int luaI_registerlocalvar (LexState *ls, TString *varname) { - FuncState *fs = ls->fs; - Proto *f = fs->f; - luaM_growvector(ls->L, f->locvars, fs->nlocvars, f->sizelocvars, - LocVar, MAX_INT, ""); - f->locvars[fs->nlocvars].varname = varname; - return fs->nlocvars++; -} - - -static void new_localvar (LexState *ls, TString *name, int n) { - FuncState *fs = ls->fs; - luaX_checklimit(ls, fs->nactvar+n+1, MAXVARS, "local variables"); - fs->actvar[fs->nactvar+n] = luaI_registerlocalvar(ls, name); -} - - -static void adjustlocalvars (LexState *ls, int nvars) { - FuncState *fs = ls->fs; - fs->nactvar += nvars; - for (; nvars; nvars--) { - getlocvar(fs, fs->nactvar - nvars).startpc = fs->pc; - } -} - - -static void removevars (LexState *ls, int tolevel) { - FuncState *fs = ls->fs; - while (fs->nactvar > tolevel) - getlocvar(fs, --fs->nactvar).endpc = fs->pc; -} - - -static void new_localvarstr (LexState *ls, const char *name, int n) { - new_localvar(ls, luaS_new(ls->L, name), n); -} - - -static void create_local (LexState *ls, const char *name) { - new_localvarstr(ls, name, 0); - adjustlocalvars(ls, 1); -} - - -static int indexupvalue (FuncState *fs, TString *name, expdesc *v) { - int i; - Proto *f = fs->f; - for (i=0; i<f->nups; i++) { - if (fs->upvalues[i].k == v->k && fs->upvalues[i].info == v->info) { - lua_assert(fs->f->upvalues[i] == name); - return i; - } - } - /* new one */ - luaX_checklimit(fs->ls, f->nups + 1, MAXUPVALUES, "upvalues"); - luaM_growvector(fs->L, fs->f->upvalues, f->nups, fs->f->sizeupvalues, - TString *, MAX_INT, ""); - fs->f->upvalues[f->nups] = name; - fs->upvalues[f->nups] = *v; - return f->nups++; -} - - -static int searchvar (FuncState *fs, TString *n) { - int i; - for (i=fs->nactvar-1; i >= 0; i--) { - if (n == getlocvar(fs, i).varname) - return i; - } - return -1; /* not found */ -} - - -static void markupval (FuncState *fs, int level) { - BlockCnt *bl = fs->bl; - while (bl && bl->nactvar > level) bl = bl->previous; - if (bl) bl->upval = 1; -} - - -static void singlevaraux (FuncState *fs, TString *n, expdesc *var, int base) { - if (fs == NULL) /* no more levels? */ - init_exp(var, VGLOBAL, NO_REG); /* default is global variable */ - else { - int v = searchvar(fs, n); /* look up at current level */ - if (v >= 0) { - init_exp(var, VLOCAL, v); - if (!base) - markupval(fs, v); /* local will be used as an upval */ - } - else { /* not found at current level; try upper one */ - singlevaraux(fs->prev, n, var, 0); - if (var->k == VGLOBAL) { - if (base) - var->info = luaK_stringK(fs, n); /* info points to global name */ - } - else { /* LOCAL or UPVAL */ - var->info = indexupvalue(fs, n, var); - var->k = VUPVAL; /* upvalue in this level */ - } - } - } -} - - -static TString *singlevar (LexState *ls, expdesc *var, int base) { - TString *varname = str_checkname(ls); - singlevaraux(ls->fs, varname, var, base); - return varname; -} - - -static void adjust_assign (LexState *ls, int nvars, int nexps, expdesc *e) { - FuncState *fs = ls->fs; - int extra = nvars - nexps; - if (e->k == VCALL) { - extra++; /* includes call itself */ - if (extra <= 0) extra = 0; - else luaK_reserveregs(fs, extra-1); - luaK_setcallreturns(fs, e, extra); /* call provides the difference */ - } - else { - if (e->k != VVOID) luaK_exp2nextreg(fs, e); /* close last expression */ - if (extra > 0) { - int reg = fs->freereg; - luaK_reserveregs(fs, extra); - luaK_nil(fs, reg, extra); - } - } -} - - -static void code_params (LexState *ls, int nparams, int dots) { - FuncState *fs = ls->fs; - adjustlocalvars(ls, nparams); - luaX_checklimit(ls, fs->nactvar, MAXPARAMS, "parameters"); - fs->f->numparams = cast(lu_byte, fs->nactvar); - fs->f->is_vararg = cast(lu_byte, dots); - if (dots) - create_local(ls, "arg"); - luaK_reserveregs(fs, fs->nactvar); /* reserve register for parameters */ -} - - -static void enterblock (FuncState *fs, BlockCnt *bl, int isbreakable) { - bl->breaklist = NO_JUMP; - bl->isbreakable = isbreakable; - bl->nactvar = fs->nactvar; - bl->upval = 0; - bl->previous = fs->bl; - fs->bl = bl; - lua_assert(fs->freereg == fs->nactvar); -} - - -static void leaveblock (FuncState *fs) { - BlockCnt *bl = fs->bl; - fs->bl = bl->previous; - removevars(fs->ls, bl->nactvar); - if (bl->upval) - luaK_codeABC(fs, OP_CLOSE, bl->nactvar, 0, 0); - lua_assert(bl->nactvar == fs->nactvar); - fs->freereg = fs->nactvar; /* free registers */ - luaK_patchtohere(fs, bl->breaklist); -} - - -static void pushclosure (LexState *ls, FuncState *func, expdesc *v) { - FuncState *fs = ls->fs; - Proto *f = fs->f; - int i; - luaM_growvector(ls->L, f->p, fs->np, f->sizep, Proto *, - MAXARG_Bx, "constant table overflow"); - f->p[fs->np++] = func->f; - init_exp(v, VRELOCABLE, luaK_codeABx(fs, OP_CLOSURE, 0, fs->np-1)); - for (i=0; i<func->f->nups; i++) { - OpCode o = (func->upvalues[i].k == VLOCAL) ? OP_MOVE : OP_GETUPVAL; - luaK_codeABC(fs, o, 0, func->upvalues[i].info, 0); - } -} - - -static void open_func (LexState *ls, FuncState *fs) { - Proto *f = luaF_newproto(ls->L); - fs->f = f; - fs->prev = ls->fs; /* linked list of funcstates */ - fs->ls = ls; - fs->L = ls->L; - ls->fs = fs; - fs->pc = 0; - fs->lasttarget = 0; - fs->jpc = NO_JUMP; - fs->freereg = 0; - fs->nk = 0; - fs->h = luaH_new(ls->L, 0, 0); - fs->np = 0; - fs->nlocvars = 0; - fs->nactvar = 0; - fs->bl = NULL; - f->source = ls->source; - f->maxstacksize = 2; /* registers 0/1 are always valid */ -} - - -static void close_func (LexState *ls) { - lua_State *L = ls->L; - FuncState *fs = ls->fs; - Proto *f = fs->f; - removevars(ls, 0); - luaK_codeABC(fs, OP_RETURN, 0, 1, 0); /* final return */ - luaM_reallocvector(L, f->code, f->sizecode, fs->pc, Instruction); - f->sizecode = fs->pc; - luaM_reallocvector(L, f->lineinfo, f->sizelineinfo, fs->pc, int); - f->sizelineinfo = fs->pc; - luaM_reallocvector(L, f->k, f->sizek, fs->nk, TObject); - f->sizek = fs->nk; - luaM_reallocvector(L, f->p, f->sizep, fs->np, Proto *); - f->sizep = fs->np; - luaM_reallocvector(L, f->locvars, f->sizelocvars, fs->nlocvars, LocVar); - f->sizelocvars = fs->nlocvars; - luaM_reallocvector(L, f->upvalues, f->sizeupvalues, f->nups, TString *); - f->sizeupvalues = f->nups; - lua_assert(luaG_checkcode(f)); - lua_assert(fs->bl == NULL); - ls->fs = fs->prev; -} - - -Proto *luaY_parser (lua_State *L, ZIO *z, Mbuffer *buff) { - struct LexState lexstate; - struct FuncState funcstate; - lexstate.buff = buff; - lexstate.nestlevel = 0; - luaX_setinput(L, &lexstate, z, luaS_new(L, zname(z))); - open_func(&lexstate, &funcstate); - next(&lexstate); /* read first token */ - chunk(&lexstate); - check_condition(&lexstate, (lexstate.t.token == TK_EOS), "<eof> expected"); - close_func(&lexstate); - lua_assert(funcstate.prev == NULL); - lua_assert(funcstate.f->nups == 0); - lua_assert(lexstate.nestlevel == 0); - return funcstate.f; -} - - - -/*============================================================*/ -/* GRAMMAR RULES */ -/*============================================================*/ - - -static void luaY_field (LexState *ls, expdesc *v) { - /* field -> ['.' | ':'] NAME */ - FuncState *fs = ls->fs; - expdesc key; - luaK_exp2anyreg(fs, v); - next(ls); /* skip the dot or colon */ - checkname(ls, &key); - luaK_indexed(fs, v, &key); -} - - -static void luaY_index (LexState *ls, expdesc *v) { - /* index -> '[' expr ']' */ - next(ls); /* skip the '[' */ - expr(ls, v); - luaK_exp2val(ls->fs, v); - check(ls, ']'); -} - - -/* -** {====================================================================== -** Rules for Constructors -** ======================================================================= -*/ - - -struct ConsControl { - expdesc v; /* last list item read */ - expdesc *t; /* table descriptor */ - int nh; /* total number of `record' elements */ - int na; /* total number of array elements */ - int tostore; /* number of array elements pending to be stored */ -}; - - -static void recfield (LexState *ls, struct ConsControl *cc) { - /* recfield -> (NAME | `['exp1`]') = exp1 */ - FuncState *fs = ls->fs; - int reg = ls->fs->freereg; - expdesc key, val; - if (ls->t.token == TK_NAME) { - luaX_checklimit(ls, cc->nh, MAX_INT, "items in a constructor"); - cc->nh++; - checkname(ls, &key); - } - else /* ls->t.token == '[' */ - luaY_index(ls, &key); - check(ls, '='); - luaK_exp2RK(fs, &key); - expr(ls, &val); - luaK_codeABC(fs, OP_SETTABLE, cc->t->info, luaK_exp2RK(fs, &key), - luaK_exp2RK(fs, &val)); - fs->freereg = reg; /* free registers */ -} - - -static void closelistfield (FuncState *fs, struct ConsControl *cc) { - if (cc->v.k == VVOID) return; /* there is no list item */ - luaK_exp2nextreg(fs, &cc->v); - cc->v.k = VVOID; - if (cc->tostore == LFIELDS_PER_FLUSH) { - luaK_codeABx(fs, OP_SETLIST, cc->t->info, cc->na-1); /* flush */ - cc->tostore = 0; /* no more items pending */ - fs->freereg = cc->t->info + 1; /* free registers */ - } -} - - -static void lastlistfield (FuncState *fs, struct ConsControl *cc) { - if (cc->tostore == 0) return; - if (cc->v.k == VCALL) { - luaK_setcallreturns(fs, &cc->v, LUA_MULTRET); - luaK_codeABx(fs, OP_SETLISTO, cc->t->info, cc->na-1); - } - else { - if (cc->v.k != VVOID) - luaK_exp2nextreg(fs, &cc->v); - luaK_codeABx(fs, OP_SETLIST, cc->t->info, cc->na-1); - } - fs->freereg = cc->t->info + 1; /* free registers */ -} - - -static void listfield (LexState *ls, struct ConsControl *cc) { - expr(ls, &cc->v); - luaX_checklimit(ls, cc->na, MAXARG_Bx, "items in a constructor"); - cc->na++; - cc->tostore++; -} - - -static void constructor (LexState *ls, expdesc *t) { - /* constructor -> ?? */ - FuncState *fs = ls->fs; - int line = ls->linenumber; - int pc = luaK_codeABC(fs, OP_NEWTABLE, 0, 0, 0); - struct ConsControl cc; - cc.na = cc.nh = cc.tostore = 0; - cc.t = t; - init_exp(t, VRELOCABLE, pc); - init_exp(&cc.v, VVOID, 0); /* no value (yet) */ - luaK_exp2nextreg(ls->fs, t); /* fix it at stack top (for gc) */ - check(ls, '{'); - do { - lua_assert(cc.v.k == VVOID || cc.tostore > 0); - testnext(ls, ';'); /* compatibility only */ - if (ls->t.token == '}') break; - closelistfield(fs, &cc); - switch(ls->t.token) { - case TK_NAME: { /* may be listfields or recfields */ - lookahead(ls); - if (ls->lookahead.token != '=') /* expression? */ - listfield(ls, &cc); - else - recfield(ls, &cc); - break; - } - case '[': { /* constructor_item -> recfield */ - recfield(ls, &cc); - break; - } - default: { /* constructor_part -> listfield */ - listfield(ls, &cc); - break; - } - } - } while (testnext(ls, ',') || testnext(ls, ';')); - check_match(ls, '}', '{', line); - lastlistfield(fs, &cc); - SETARG_B(fs->f->code[pc], luaO_int2fb(cc.na)); /* set initial array size */ - SETARG_C(fs->f->code[pc], luaO_log2(cc.nh)+1); /* set initial table size */ -} - -/* }====================================================================== */ - - - -static void parlist (LexState *ls) { - /* parlist -> [ param { `,' param } ] */ - int nparams = 0; - int dots = 0; - if (ls->t.token != ')') { /* is `parlist' not empty? */ - do { - switch (ls->t.token) { - case TK_DOTS: dots = 1; next(ls); break; - case TK_NAME: new_localvar(ls, str_checkname(ls), nparams++); break; - default: luaX_syntaxerror(ls, "<name> or `...' expected"); - } - } while (!dots && testnext(ls, ',')); - } - code_params(ls, nparams, dots); -} - - -static void body (LexState *ls, expdesc *e, int needself, int line) { - /* body -> `(' parlist `)' chunk END */ - FuncState new_fs; - open_func(ls, &new_fs); - new_fs.f->lineDefined = line; - check(ls, '('); - if (needself) - create_local(ls, "self"); - parlist(ls); - check(ls, ')'); - chunk(ls); - check_match(ls, TK_END, TK_FUNCTION, line); - close_func(ls); - pushclosure(ls, &new_fs, e); -} - - -static int explist1 (LexState *ls, expdesc *v) { - /* explist1 -> expr { `,' expr } */ - int n = 1; /* at least one expression */ - expr(ls, v); - while (testnext(ls, ',')) { - luaK_exp2nextreg(ls->fs, v); - expr(ls, v); - n++; - } - return n; -} - - -static void funcargs (LexState *ls, expdesc *f) { - FuncState *fs = ls->fs; - expdesc args; - int base, nparams; - int line = ls->linenumber; - switch (ls->t.token) { - case '(': { /* funcargs -> `(' [ explist1 ] `)' */ - if (line != ls->lastline) - luaX_syntaxerror(ls,"ambiguous syntax (function call x new statement)"); - next(ls); - if (ls->t.token == ')') /* arg list is empty? */ - args.k = VVOID; - else { - explist1(ls, &args); - luaK_setcallreturns(fs, &args, LUA_MULTRET); - } - check_match(ls, ')', '(', line); - break; - } - case '{': { /* funcargs -> constructor */ - constructor(ls, &args); - break; - } - case TK_STRING: { /* funcargs -> STRING */ - codestring(ls, &args, ls->t.seminfo.ts); - next(ls); /* must use `seminfo' before `next' */ - break; - } - default: { - luaX_syntaxerror(ls, "function arguments expected"); - return; - } - } - lua_assert(f->k == VNONRELOC); - base = f->info; /* base register for call */ - if (args.k == VCALL) - nparams = LUA_MULTRET; /* open call */ - else { - if (args.k != VVOID) - luaK_exp2nextreg(fs, &args); /* close last argument */ - nparams = fs->freereg - (base+1); - } - 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 */ -} - - - - -/* -** {====================================================================== -** Expression parsing -** ======================================================================= -*/ - - -static void prefixexp (LexState *ls, expdesc *v) { - /* prefixexp -> NAME | '(' expr ')' */ - switch (ls->t.token) { - case '(': { - int line = ls->linenumber; - next(ls); - expr(ls, v); - check_match(ls, ')', '(', line); - luaK_dischargevars(ls->fs, v); - return; - } - case TK_NAME: { - singlevar(ls, v, 1); - return; - } -#ifdef LUA_COMPATUPSYNTAX - case '%': { /* for compatibility only */ - TString *varname; - int line = ls->linenumber; - next(ls); /* skip `%' */ - varname = singlevar(ls, v, 1); - if (v->k != VUPVAL) - luaX_errorline(ls, "global upvalues are obsolete", - getstr(varname), line); - return; - } -#endif - default: { - luaX_syntaxerror(ls, "unexpected symbol"); - return; - } - } -} - - -static void primaryexp (LexState *ls, expdesc *v) { - /* primaryexp -> - prefixexp { `.' NAME | `[' exp `]' | `:' NAME funcargs | funcargs } */ - FuncState *fs = ls->fs; - prefixexp(ls, v); - for (;;) { - switch (ls->t.token) { - case '.': { /* field */ - luaY_field(ls, v); - break; - } - case '[': { /* `[' exp1 `]' */ - expdesc key; - luaK_exp2anyreg(fs, v); - luaY_index(ls, &key); - luaK_indexed(fs, v, &key); - break; - } - case ':': { /* `:' NAME funcargs */ - expdesc key; - next(ls); - checkname(ls, &key); - luaK_self(fs, v, &key); - funcargs(ls, v); - break; - } - case '(': case TK_STRING: case '{': { /* funcargs */ - luaK_exp2nextreg(fs, v); - funcargs(ls, v); - break; - } - default: return; - } - } -} - - -static void simpleexp (LexState *ls, expdesc *v) { - /* simpleexp -> NUMBER | STRING | NIL | constructor | FUNCTION body - | primaryexp */ - switch (ls->t.token) { - case TK_NUMBER: { - init_exp(v, VK, luaK_numberK(ls->fs, ls->t.seminfo.r)); - next(ls); /* must use `seminfo' before `next' */ - break; - } - case TK_STRING: { - codestring(ls, v, ls->t.seminfo.ts); - next(ls); /* must use `seminfo' before `next' */ - break; - } - case TK_NIL: { - init_exp(v, VNIL, 0); - next(ls); - break; - } - case TK_TRUE: { - init_exp(v, VTRUE, 0); - next(ls); - break; - } - case TK_FALSE: { - init_exp(v, VFALSE, 0); - next(ls); - break; - } - case '{': { /* constructor */ - constructor(ls, v); - break; - } - case TK_FUNCTION: { - next(ls); - body(ls, v, 0, ls->linenumber); - break; - } - default: { - primaryexp(ls, v); - break; - } - } -} - - -static UnOpr getunopr (int op) { - switch (op) { - case TK_NOT: return OPR_NOT; - case '-': return OPR_MINUS; - default: return OPR_NOUNOPR; - } -} - - -static BinOpr getbinopr (int op) { - switch (op) { - case '+': return OPR_ADD; - case '-': return OPR_SUB; - case '*': return OPR_MULT; - case '/': return OPR_DIV; - case '^': return OPR_POW; - case TK_CONCAT: return OPR_CONCAT; - case TK_NE: return OPR_NE; - case TK_EQ: return OPR_EQ; - case '<': return OPR_LT; - case TK_LE: return OPR_LE; - case '>': return OPR_GT; - case TK_GE: return OPR_GE; - case TK_AND: return OPR_AND; - case TK_OR: return OPR_OR; - default: return OPR_NOBINOPR; - } -} - - -static const struct { - lu_byte left; /* left priority for each binary operator */ - lu_byte right; /* right priority */ -} priority[] = { /* ORDER OPR */ - {6, 6}, {6, 6}, {7, 7}, {7, 7}, /* arithmetic */ - {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) */ -}; - -#define UNARY_PRIORITY 8 /* priority for unary operators */ - - -/* -** subexpr -> (simplexep | unop subexpr) { binop subexpr } -** where `binop' is any binary operator with a priority higher than `limit' -*/ -static BinOpr subexpr (LexState *ls, expdesc *v, int limit) { - BinOpr op; - UnOpr uop; - enterlevel(ls); - uop = getunopr(ls->t.token); - if (uop != OPR_NOUNOPR) { - next(ls); - subexpr(ls, v, UNARY_PRIORITY); - luaK_prefix(ls->fs, uop, v); - } - else simpleexp(ls, v); - /* expand while operators have priorities higher than `limit' */ - op = getbinopr(ls->t.token); - while (op != OPR_NOBINOPR && cast(int, priority[op].left) > limit) { - expdesc v2; - BinOpr nextop; - next(ls); - luaK_infix(ls->fs, op, v); - /* read sub-expression with higher priority */ - nextop = subexpr(ls, &v2, cast(int, priority[op].right)); - luaK_posfix(ls->fs, op, v, &v2); - op = nextop; - } - leavelevel(ls); - return op; /* return first untreated operator */ -} - - -static void expr (LexState *ls, expdesc *v) { - subexpr(ls, v, -1); -} - -/* }==================================================================== */ - - - -/* -** {====================================================================== -** Rules for Statements -** ======================================================================= -*/ - - -static int block_follow (int token) { - switch (token) { - case TK_ELSE: case TK_ELSEIF: case TK_END: - case TK_UNTIL: case TK_EOS: - return 1; - default: return 0; - } -} - - -static void block (LexState *ls) { - /* block -> chunk */ - FuncState *fs = ls->fs; - BlockCnt bl; - enterblock(fs, &bl, 0); - chunk(ls); - lua_assert(bl.breaklist == NO_JUMP); - leaveblock(fs); -} - - -/* -** structure to chain all variables in the left-hand side of an -** assignment -*/ -struct LHS_assign { - struct LHS_assign *prev; - expdesc v; /* variable (global, local, upvalue, or indexed) */ -}; - - -/* -** 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. -*/ -static void check_conflict (LexState *ls, struct LHS_assign *lh, expdesc *v) { - FuncState *fs = ls->fs; - int extra = fs->freereg; /* eventual position to save local variable */ - int conflict = 0; - for (; lh; lh = lh->prev) { - if (lh->v.k == VINDEXED) { - if (lh->v.info == v->info) { /* conflict? */ - conflict = 1; - lh->v.info = extra; /* previous assignment will use safe copy */ - } - if (lh->v.aux == v->info) { /* conflict? */ - conflict = 1; - lh->v.aux = extra; /* previous assignment will use safe copy */ - } - } - } - if (conflict) { - luaK_codeABC(fs, OP_MOVE, fs->freereg, v->info, 0); /* make copy */ - luaK_reserveregs(fs, 1); - } -} - - -static void assignment (LexState *ls, struct LHS_assign *lh, int nvars) { - expdesc e; - check_condition(ls, VLOCAL <= lh->v.k && lh->v.k <= VINDEXED, - "syntax error"); - if (testnext(ls, ',')) { /* assignment -> `,' primaryexp assignment */ - struct LHS_assign nv; - nv.prev = lh; - primaryexp(ls, &nv.v); - if (nv.v.k == VLOCAL) - check_conflict(ls, lh, &nv.v); - assignment(ls, &nv, nvars+1); - } - else { /* assignment -> `=' explist1 */ - int nexps; - check(ls, '='); - nexps = explist1(ls, &e); - if (nexps != nvars) { - adjust_assign(ls, nvars, nexps, &e); - if (nexps > nvars) - ls->fs->freereg -= nexps - nvars; /* remove extra values */ - } - else { - luaK_setcallreturns(ls->fs, &e, 1); /* close last expression */ - luaK_storevar(ls->fs, &lh->v, &e); - return; /* avoid default */ - } - } - init_exp(&e, VNONRELOC, ls->fs->freereg-1); /* default assignment */ - luaK_storevar(ls->fs, &lh->v, &e); -} - - -static void cond (LexState *ls, expdesc *v) { - /* cond -> exp */ - expr(ls, v); /* read condition */ - if (v->k == VNIL) v->k = VFALSE; /* `falses' are all equal here */ - luaK_goiftrue(ls->fs, v); - luaK_patchtohere(ls->fs, v->t); -} - - -/* -** The while statement optimizes its code by coding the condition -** after its body (and thus avoiding one jump in the loop). -*/ - -/* -** maximum size of expressions for optimizing `while' code -*/ -#ifndef MAXEXPWHILE -#define MAXEXPWHILE 100 -#endif - -/* -** the call `luaK_goiffalse' may grow the size of an expression by -** at most this: -*/ -#define EXTRAEXP 5 - -static void whilestat (LexState *ls, int line) { - /* whilestat -> WHILE cond DO block END */ - Instruction codeexp[MAXEXPWHILE + EXTRAEXP]; - int lineexp; - int i; - int sizeexp; - FuncState *fs = ls->fs; - int whileinit, blockinit, expinit; - expdesc v; - BlockCnt bl; - next(ls); /* skip WHILE */ - whileinit = luaK_jump(fs); /* jump to condition (which will be moved) */ - expinit = luaK_getlabel(fs); - expr(ls, &v); /* parse condition */ - if (v.k == VK) v.k = VTRUE; /* `trues' are all equal here */ - lineexp = ls->linenumber; - luaK_goiffalse(fs, &v); - luaK_concat(fs, &v.f, fs->jpc); - fs->jpc = NO_JUMP; - sizeexp = fs->pc - expinit; /* size of expression code */ - if (sizeexp > MAXEXPWHILE) - luaX_syntaxerror(ls, "`while' condition too complex"); - for (i = 0; i < sizeexp; i++) /* save `exp' code */ - codeexp[i] = fs->f->code[expinit + i]; - fs->pc = expinit; /* remove `exp' code */ - enterblock(fs, &bl, 1); - check(ls, TK_DO); - blockinit = luaK_getlabel(fs); - block(ls); - luaK_patchtohere(fs, whileinit); /* initial jump jumps to here */ - /* move `exp' back to code */ - if (v.t != NO_JUMP) v.t += fs->pc - expinit; - if (v.f != NO_JUMP) v.f += fs->pc - expinit; - for (i=0; i<sizeexp; i++) - luaK_code(fs, codeexp[i], lineexp); - check_match(ls, TK_END, TK_WHILE, line); - leaveblock(fs); - luaK_patchlist(fs, v.t, blockinit); /* true conditions go back to loop */ - luaK_patchtohere(fs, v.f); /* false conditions finish the loop */ -} - - -static void repeatstat (LexState *ls, int line) { - /* repeatstat -> REPEAT block UNTIL cond */ - FuncState *fs = ls->fs; - int repeat_init = luaK_getlabel(fs); - expdesc v; - BlockCnt bl; - enterblock(fs, &bl, 1); - next(ls); - block(ls); - check_match(ls, TK_UNTIL, TK_REPEAT, line); - cond(ls, &v); - luaK_patchlist(fs, v.f, repeat_init); - leaveblock(fs); -} - - -static int exp1 (LexState *ls) { - expdesc e; - int k; - expr(ls, &e); - k = e.k; - luaK_exp2nextreg(ls->fs, &e); - return k; -} - - -static void forbody (LexState *ls, int base, int line, int nvars, int isnum) { - BlockCnt bl; - FuncState *fs = ls->fs; - int prep, endfor; - adjustlocalvars(ls, nvars); /* scope for all variables */ - check(ls, TK_DO); - enterblock(fs, &bl, 1); /* loop block */ - prep = luaK_getlabel(fs); - block(ls); - luaK_patchtohere(fs, prep-1); - endfor = (isnum) ? luaK_codeAsBx(fs, OP_FORLOOP, base, NO_JUMP) : - luaK_codeABC(fs, OP_TFORLOOP, base, 0, nvars - 3); - luaK_fixline(fs, line); /* pretend that `OP_FOR' starts the loop */ - luaK_patchlist(fs, (isnum) ? endfor : luaK_jump(fs), prep); - leaveblock(fs); -} - - -static void fornum (LexState *ls, TString *varname, int line) { - /* fornum -> NAME = exp1,exp1[,exp1] DO body */ - FuncState *fs = ls->fs; - int base = fs->freereg; - new_localvar(ls, varname, 0); - new_localvarstr(ls, "(for limit)", 1); - new_localvarstr(ls, "(for step)", 2); - check(ls, '='); - exp1(ls); /* initial value */ - check(ls, ','); - exp1(ls); /* limit */ - if (testnext(ls, ',')) - exp1(ls); /* optional step */ - else { /* default step = 1 */ - luaK_codeABx(fs, OP_LOADK, fs->freereg, luaK_numberK(fs, 1)); - luaK_reserveregs(fs, 1); - } - luaK_codeABC(fs, OP_SUB, fs->freereg - 3, fs->freereg - 3, fs->freereg - 1); - luaK_jump(fs); - forbody(ls, base, line, 3, 1); -} - - -static void forlist (LexState *ls, TString *indexname) { - /* forlist -> NAME {,NAME} IN explist1 DO body */ - FuncState *fs = ls->fs; - expdesc e; - int nvars = 0; - int line; - int base = fs->freereg; - new_localvarstr(ls, "(for generator)", nvars++); - new_localvarstr(ls, "(for state)", nvars++); - new_localvar(ls, indexname, nvars++); - while (testnext(ls, ',')) - new_localvar(ls, str_checkname(ls), nvars++); - check(ls, TK_IN); - line = ls->linenumber; - adjust_assign(ls, nvars, explist1(ls, &e), &e); - luaK_checkstack(fs, 3); /* extra space to call generator */ - luaK_codeAsBx(fs, OP_TFORPREP, base, NO_JUMP); - forbody(ls, base, line, nvars, 0); -} - - -static void forstat (LexState *ls, int line) { - /* forstat -> fornum | forlist */ - FuncState *fs = ls->fs; - TString *varname; - BlockCnt bl; - enterblock(fs, &bl, 0); /* block to control variable scope */ - next(ls); /* skip `for' */ - varname = str_checkname(ls); /* first variable name */ - switch (ls->t.token) { - case '=': fornum(ls, varname, line); break; - case ',': case TK_IN: forlist(ls, varname); break; - default: luaX_syntaxerror(ls, "`=' or `in' expected"); - } - check_match(ls, TK_END, TK_FOR, line); - leaveblock(fs); -} - - -static void test_then_block (LexState *ls, expdesc *v) { - /* test_then_block -> [IF | ELSEIF] cond THEN block */ - next(ls); /* skip IF or ELSEIF */ - cond(ls, v); - check(ls, TK_THEN); - block(ls); /* `then' part */ -} - - -static void ifstat (LexState *ls, int line) { - /* ifstat -> IF cond THEN block {ELSEIF cond THEN block} [ELSE block] END */ - FuncState *fs = ls->fs; - expdesc v; - int escapelist = NO_JUMP; - test_then_block(ls, &v); /* IF cond THEN block */ - while (ls->t.token == TK_ELSEIF) { - luaK_concat(fs, &escapelist, luaK_jump(fs)); - luaK_patchtohere(fs, v.f); - test_then_block(ls, &v); /* ELSEIF cond THEN block */ - } - if (ls->t.token == TK_ELSE) { - luaK_concat(fs, &escapelist, luaK_jump(fs)); - luaK_patchtohere(fs, v.f); - next(ls); /* skip ELSE (after patch, for correct line info) */ - block(ls); /* `else' part */ - } - else - luaK_concat(fs, &escapelist, v.f); - luaK_patchtohere(fs, escapelist); - check_match(ls, TK_END, TK_IF, line); -} - - -static void localfunc (LexState *ls) { - expdesc v, b; - new_localvar(ls, str_checkname(ls), 0); - init_exp(&v, VLOCAL, ls->fs->freereg++); - adjustlocalvars(ls, 1); - body(ls, &b, 0, ls->linenumber); - luaK_storevar(ls->fs, &v, &b); -} - - -static void localstat (LexState *ls) { - /* stat -> LOCAL NAME {`,' NAME} [`=' explist1] */ - int nvars = 0; - int nexps; - expdesc e; - do { - new_localvar(ls, str_checkname(ls), nvars++); - } while (testnext(ls, ',')); - if (testnext(ls, '=')) - nexps = explist1(ls, &e); - else { - e.k = VVOID; - nexps = 0; - } - adjust_assign(ls, nvars, nexps, &e); - adjustlocalvars(ls, nvars); -} - - -static int funcname (LexState *ls, expdesc *v) { - /* funcname -> NAME {field} [`:' NAME] */ - int needself = 0; - singlevar(ls, v, 1); - while (ls->t.token == '.') - luaY_field(ls, v); - if (ls->t.token == ':') { - needself = 1; - luaY_field(ls, v); - } - return needself; -} - - -static void funcstat (LexState *ls, int line) { - /* funcstat -> FUNCTION funcname body */ - int needself; - expdesc v, b; - next(ls); /* skip FUNCTION */ - needself = funcname(ls, &v); - body(ls, &b, needself, line); - luaK_storevar(ls->fs, &v, &b); - luaK_fixline(ls->fs, line); /* definition `happens' in the first line */ -} - - -static void exprstat (LexState *ls) { - /* stat -> func | assignment */ - FuncState *fs = ls->fs; - struct LHS_assign v; - primaryexp(ls, &v.v); - if (v.v.k == VCALL) { /* stat -> func */ - luaK_setcallreturns(fs, &v.v, 0); /* call statement uses no results */ - } - else { /* stat -> assignment */ - v.prev = NULL; - assignment(ls, &v, 1); - } -} - - -static void retstat (LexState *ls) { - /* stat -> RETURN explist */ - FuncState *fs = ls->fs; - expdesc e; - int first, nret; /* registers with returned values */ - next(ls); /* skip RETURN */ - if (block_follow(ls->t.token) || ls->t.token == ';') - first = nret = 0; /* return no values */ - else { - nret = explist1(ls, &e); /* optional return values */ - if (e.k == VCALL) { - luaK_setcallreturns(fs, &e, LUA_MULTRET); - if (nret == 1) { /* tail call? */ - SET_OPCODE(getcode(fs,&e), OP_TAILCALL); - lua_assert(GETARG_A(getcode(fs,&e)) == fs->nactvar); - } - first = fs->nactvar; - nret = LUA_MULTRET; /* return all values */ - } - else { - if (nret == 1) /* 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); - } - } - } - luaK_codeABC(fs, OP_RETURN, first, nret+1, 0); -} - - -static void breakstat (LexState *ls) { - /* stat -> BREAK [NAME] */ - FuncState *fs = ls->fs; - BlockCnt *bl = fs->bl; - int upval = 0; - next(ls); /* skip BREAK */ - while (bl && !bl->isbreakable) { - upval |= bl->upval; - bl = bl->previous; - } - if (!bl) - luaX_syntaxerror(ls, "no loop to break"); - if (upval) - luaK_codeABC(fs, OP_CLOSE, bl->nactvar, 0, 0); - luaK_concat(fs, &bl->breaklist, luaK_jump(fs)); -} - - -static int statement (LexState *ls) { - int line = ls->linenumber; /* may be needed for error messages */ - switch (ls->t.token) { - case TK_IF: { /* stat -> ifstat */ - ifstat(ls, line); - return 0; - } - case TK_WHILE: { /* stat -> whilestat */ - whilestat(ls, line); - return 0; - } - case TK_DO: { /* stat -> DO block END */ - next(ls); /* skip DO */ - block(ls); - check_match(ls, TK_END, TK_DO, line); - return 0; - } - case TK_FOR: { /* stat -> forstat */ - forstat(ls, line); - return 0; - } - case TK_REPEAT: { /* stat -> repeatstat */ - repeatstat(ls, line); - return 0; - } - case TK_FUNCTION: { - funcstat(ls, line); /* stat -> funcstat */ - return 0; - } - case TK_LOCAL: { /* stat -> localstat */ - next(ls); /* skip LOCAL */ - if (testnext(ls, TK_FUNCTION)) /* local function? */ - localfunc(ls); - else - localstat(ls); - return 0; - } - case TK_RETURN: { /* stat -> retstat */ - retstat(ls); - return 1; /* must be last statement */ - } - case TK_BREAK: { /* stat -> breakstat */ - breakstat(ls); - return 1; /* must be last statement */ - } - default: { - exprstat(ls); - return 0; /* to avoid warnings */ - } - } -} - - -static void chunk (LexState *ls) { - /* chunk -> { stat [`;'] } */ - int islast = 0; - enterlevel(ls); - while (!islast && !block_follow(ls->t.token)) { - islast = statement(ls); - testnext(ls, ';'); - lua_assert(ls->fs->freereg >= ls->fs->nactvar); - ls->fs->freereg = ls->fs->nactvar; /* free registers */ - } - leavelevel(ls); -} - -/* }====================================================================== */ |