commit dbfb810267d8fd7ecf546ea1e1edc8892547e664
parent 9c14b5e416e1ca3ebed37c4ceb860579124ac29f
Author: Roberto Ierusalimschy <roberto@inf.puc-rio.br>
Date: Mon, 5 Jun 2000 11:55:56 -0300
cleansing of lparser.c
Diffstat:
| M | lcode.c | | | 38 | ++++++++++++++++++++++---------------- |
| M | lgc.c | | | 11 | ++++++++--- |
| M | lopcodes.h | | | 4 | ++-- |
| M | lparser.c | | | 416 | ++++++++++++++++++++++++++++++++++--------------------------------------------- |
| M | lvm.c | | | 25 | ++++++++++++------------- |
5 files changed, 223 insertions(+), 271 deletions(-)
diff --git a/lcode.c b/lcode.c
@@ -1,5 +1,5 @@
/*
-** $Id: lcode.c,v 1.32 2000/05/24 13:54:49 roberto Exp roberto $
+** $Id: lcode.c,v 1.33 2000/05/24 18:04:17 roberto Exp roberto $
** Code generator for Lua
** See Copyright Notice in lua.h
*/
@@ -69,16 +69,16 @@ static int luaK_getjump (FuncState *fs, int pc) {
/*
-** discharge list of jumps to last target.
** returns current `pc' and marks it as a jump target (to avoid wrong
** optimizations with consecutive instructions not in the same basic block).
+** discharge list of jumps to last target.
*/
int luaK_getlabel (FuncState *fs) {
if (fs->pc != fs->lasttarget) {
int lasttarget = fs->lasttarget;
fs->lasttarget = fs->pc;
luaK_patchlist(fs, fs->jlt, lasttarget); /* discharge old list `jlt' */
- fs->jlt = NO_JUMP; /* nobody jumps to this new label (till now) */
+ fs->jlt = NO_JUMP; /* nobody jumps to this new label (yet) */
}
return fs->pc;
}
@@ -86,7 +86,7 @@ int luaK_getlabel (FuncState *fs) {
void luaK_deltastack (FuncState *fs, int delta) {
fs->stacklevel += delta;
- if (delta > 0 && fs->stacklevel > fs->f->maxstacksize) {
+ if (fs->stacklevel > fs->f->maxstacksize) {
if (fs->stacklevel > MAXSTACK)
luaK_error(fs->ls, "function or expression too complex");
fs->f->maxstacksize = fs->stacklevel;
@@ -99,7 +99,7 @@ void luaK_kstr (LexState *ls, int c) {
}
-static int real_constant (FuncState *fs, Number r) {
+static int number_constant (FuncState *fs, Number r) {
/* check whether `r' has appeared within the last LOOKBACKNUMS entries */
Proto *f = fs->f;
int c = f->nknum;
@@ -116,17 +116,17 @@ static int real_constant (FuncState *fs, Number r) {
void luaK_number (FuncState *fs, Number f) {
- if (f <= (Number)MAXARG_S && (int)f == f)
+ if (f <= (Number)MAXARG_S && (Number)(int)f == f)
luaK_code1(fs, OP_PUSHINT, (int)f); /* f has a short integer value */
else
- luaK_code1(fs, OP_PUSHNUM, real_constant(fs, f));
+ luaK_code1(fs, OP_PUSHNUM, number_constant(fs, f));
}
void luaK_adjuststack (FuncState *fs, int n) {
if (n > 0)
luaK_code1(fs, OP_POP, n);
- else if (n < 0)
+ else
luaK_code1(fs, OP_PUSHNIL, -n);
}
@@ -170,7 +170,7 @@ static int discharge (FuncState *fs, expdesc *var) {
static void discharge1 (FuncState *fs, expdesc *var) {
discharge(fs, var);
- /* if it has jumps it is already discharged */
+ /* if it has jumps then it is already discharged */
if (var->u.l.t == NO_JUMP && var->u.l.f == NO_JUMP)
luaK_setcallreturns(fs, 1); /* call must return 1 value */
}
@@ -275,12 +275,10 @@ static void luaK_testgo (FuncState *fs, expdesc *v, int invert, OpCode jump) {
discharge1(fs, v);
previous = &fs->f->code[fs->pc-1];
LUA_ASSERT(L, GET_OPCODE(*previous) != OP_SETLINE, "bad place to set line");
- if (ISJUMP(GET_OPCODE(*previous))) {
- if (invert)
- SET_OPCODE(*previous, invertjump(GET_OPCODE(*previous)));
- }
- else
+ if (!ISJUMP(GET_OPCODE(*previous)))
luaK_code1(fs, jump, NO_JUMP);
+ else if (invert)
+ SET_OPCODE(*previous, invertjump(GET_OPCODE(*previous)));
luaK_concat(fs, exitlist, fs->pc-1); /* insert last jump in `exitlist' */
luaK_patchlist(fs, *golist, luaK_getlabel(fs));
*golist = NO_JUMP;
@@ -431,12 +429,17 @@ int luaK_code2 (FuncState *fs, OpCode o, int arg1, int arg2) {
break;
case OP_SETTABLE:
+ delta = -arg2;
+ break;
+
case OP_SETLIST:
+ if (arg2 == 0) return NO_JUMP; /* nothing to do */
delta = -arg2;
break;
case OP_SETMAP:
- delta = -2*(arg1+1);
+ if (arg1 == 0) return NO_JUMP; /* nothing to do */
+ delta = -2*arg1;
break;
case OP_RETURN:
@@ -448,6 +451,7 @@ int luaK_code2 (FuncState *fs, OpCode o, int arg1, int arg2) {
break;
case OP_PUSHNIL:
+ if (arg1 == 0) return NO_JUMP; /* nothing to do */
delta = arg1;
switch(GET_OPCODE(i)) {
case OP_PUSHNIL: SETARG_U(i, GETARG_U(i)+arg1); optm = 1; break;
@@ -456,6 +460,7 @@ int luaK_code2 (FuncState *fs, OpCode o, int arg1, int arg2) {
break;
case OP_POP:
+ if (arg1 == 0) return NO_JUMP; /* nothing to do */
delta = -arg1;
switch(GET_OPCODE(i)) {
case OP_SETTABLE: SETARG_B(i, GETARG_B(i)+arg1); optm = 1; break;
@@ -561,13 +566,14 @@ int luaK_code2 (FuncState *fs, OpCode o, int arg1, int arg2) {
fs->f->code[fs->pc-1] = i; /* change previous instruction */
return fs->pc-1; /* do not generate new instruction */
}
+ /* build new instruction */
switch ((enum Mode)luaK_opproperties[o].mode) {
case iO: i = CREATE_0(o); break;
case iU: i = CREATE_U(o, arg1); break;
case iS: i = CREATE_S(o, arg1); break;
case iAB: i = CREATE_AB(o, arg1, arg2); break;
}
- /* actually create the new instruction */
+ /* put new instruction in code array */
luaM_growvector(fs->L, fs->f->code, fs->pc, 1, Instruction,
"code size overflow", MAX_INT);
fs->f->code[fs->pc] = i;
diff --git a/lgc.c b/lgc.c
@@ -1,5 +1,5 @@
/*
-** $Id: lgc.c,v 1.52 2000/05/30 18:54:49 roberto Exp roberto $
+** $Id: lgc.c,v 1.53 2000/05/30 19:00:31 roberto Exp roberto $
** Garbage Collector
** See Copyright Notice in lua.h
*/
@@ -34,10 +34,15 @@ static void protomark (lua_State *L, Proto *f) {
int i;
f->marked = 1;
strmark(L, f->source);
- for (i=f->nkstr-1; i>=0; i--)
+ for (i=0; i<f->nkstr; i++)
strmark(L, f->kstr[i]);
- for (i=f->nkproto-1; i>=0; i--)
+ for (i=0; i<f->nkproto; i++)
protomark(L, f->kproto[i]);
+ if (f->locvars) { /* is there debug information? */
+ LocVar *lv;
+ for (lv=f->locvars; lv->line != -1; lv++) /* mark local-variable names */
+ if (lv->varname) strmark(L, lv->varname);
+ }
}
}
diff --git a/lopcodes.h b/lopcodes.h
@@ -1,5 +1,5 @@
/*
-** $Id: lopcodes.h,v 1.61 2000/05/15 19:48:04 roberto Exp roberto $
+** $Id: lopcodes.h,v 1.62 2000/05/22 18:44:46 roberto Exp roberto $
** Opcodes for Lua virtual machine
** See Copyright Notice in lua.h
*/
@@ -113,7 +113,7 @@ OP_SETGLOBAL,/* K x - VAR[KSTR[k]]=x */
OP_SETTABLE,/* A B v a_a-a_1 i t (pops b values) t[i]=v */
OP_SETLIST,/* A B v_b-v_1 t t t[i+a*FPF]=v_i */
-OP_SETMAP,/* U v_u k_u - v_0 k_0 t t t[k_i]=v_i */
+OP_SETMAP,/* U v_u k_u - v_1 k_1 t t t[k_i]=v_i */
OP_ADD,/* - y x x+y */
OP_ADDI,/* S x x+s */
diff --git a/lparser.c b/lparser.c
@@ -1,5 +1,5 @@
/*
-** $Id: lparser.c,v 1.92 2000/05/25 18:59:59 roberto Exp roberto $
+** $Id: lparser.c,v 1.93 2000/05/30 19:00:31 roberto Exp roberto $
** LL(1) Parser and code generator for Lua
** See Copyright Notice in lua.h
*/
@@ -11,7 +11,6 @@
#define LUA_REENTRANT
#include "lcode.h"
-#include "ldo.h"
#include "lfunc.h"
#include "llex.h"
#include "lmem.h"
@@ -79,11 +78,6 @@ static void error_expected (LexState *ls, int token) {
}
-static void error_unexpected (LexState *ls) {
- luaK_error(ls, "unexpected token");
-}
-
-
static void check (LexState *ls, int c) {
if (ls->t.token != c)
error_expected(ls, c);
@@ -91,6 +85,11 @@ static void check (LexState *ls, int c) {
}
+static void check_condition (LexState *ls, int c, const char *msg) {
+ if (!c) luaK_error(ls, msg);
+}
+
+
static void setline (LexState *ls) {
FuncState *fs = ls->fs;
if (ls->L->debug && ls->linenumber != fs->lastsetline) {
@@ -159,27 +158,17 @@ static void code_string (LexState *ls, TString *s) {
}
-static int checkname (LexState *ls) {
- int sc;
- if (ls->t.token != TK_NAME)
- luaK_error(ls, "<name> expected");
- sc = string_constant(ls->fs, ls->t.seminfo.ts);
- next(ls);
- return sc;
-}
-
-
static TString *str_checkname (LexState *ls) {
- int i = checkname(ls); /* this call may realloc `f->kstr' */
- return ls->fs->f->kstr[i];
+ TString *ts;
+ check_condition(ls, (ls->t.token == TK_NAME), "<name> expected");
+ ts = ls->t.seminfo.ts;
+ next(ls);
+ return ts;
}
-static TString *optionalname (LexState *ls) {
- if (ls->t.token == TK_NAME)
- return str_checkname(ls);
- else
- return NULL;
+static int checkname (LexState *ls) {
+ return string_constant(ls->fs, str_checkname(ls));
}
@@ -229,94 +218,90 @@ static void add_localvar (LexState *ls, const char *name) {
}
-static int aux_localname (FuncState *fs, TString *n) {
- int i;
- for (i=fs->nlocalvar-1; i >= 0; i--)
- if (n == fs->localvar[i]) return i; /* local var index */
- return -1; /* not found */
+static int search_local (LexState *ls, TString *n, expdesc *var) {
+ FuncState *fs;
+ int level = 0;
+ for (fs=ls->fs; fs; fs=fs->prev) {
+ int i;
+ for (i=fs->nlocalvar-1; i >= 0; i--) {
+ if (n == fs->localvar[i]) {
+ var->k = VLOCAL;
+ var->u.index = i;
+ return level;
+ }
+ }
+ level++; /* `var' not found; check outer level */
+ }
+ var->k = VGLOBAL; /* not found in any level; must be global */
+ return -1;
}
-static void singlevar (LexState *ls, TString *n, expdesc *var, int prev) {
- FuncState *fs = prev ? ls->fs->prev : ls->fs;
- int i = aux_localname(fs, n);
- if (i >= 0) { /* local value? */
- var->k = VLOCAL;
- var->u.index = i;
- }
- else {
- FuncState *level = fs;
- while ((level = level->prev) != NULL) /* check shadowing */
- if (aux_localname(level, n) >= 0)
- luaX_syntaxerror(ls, "cannot access a variable in outer scope", n->str);
- var->k = VGLOBAL;
- var->u.index = string_constant(fs, n);
- }
+static void singlevar (LexState *ls, TString *n, expdesc *var) {
+ int level = search_local(ls, n, var);
+ if (level >= 1) /* neither local (0) nor global (-1)? */
+ luaX_syntaxerror(ls, "cannot access a variable in outer scope", n->str);
+ else if (level == -1) /* global? */
+ var->u.index = string_constant(ls->fs, n);
}
-static int indexupvalue (LexState *ls, TString *n) {
+static int indexupvalue (LexState *ls, expdesc *v) {
FuncState *fs = ls->fs;
- expdesc v;
int i;
- singlevar(ls, n, &v, 1);
for (i=0; i<fs->nupvalues; i++) {
- if (fs->upvalues[i].k == v.k && fs->upvalues[i].u.index == v.u.index)
+ if (fs->upvalues[i].k == v->k && fs->upvalues[i].u.index == v->u.index)
return i;
}
/* new one */
- ++(fs->nupvalues);
- luaX_checklimit(ls, fs->nupvalues, MAXUPVALUES, "upvalues");
- fs->upvalues[i] = v; /* i = fs->nupvalues - 1 */
- return i;
+ luaX_checklimit(ls, fs->nupvalues+1, MAXUPVALUES, "upvalues");
+ fs->upvalues[fs->nupvalues] = *v;
+ return fs->nupvalues++;
}
static void pushupvalue (LexState *ls, TString *n) {
FuncState *fs = ls->fs;
- if (fs->prev == NULL)
- luaX_syntaxerror(ls, "cannot access upvalue in main", n->str);
- if (aux_localname(ls->fs, n) >= 0)
- luaX_syntaxerror(ls, "cannot access an upvalue in current scope", n->str);
- luaK_code1(fs, OP_PUSHUPVALUE, indexupvalue(ls, n));
+ expdesc v;
+ int level = search_local(ls, n, &v);
+ if (level == -1) { /* global? */
+ if (fs->prev == NULL)
+ luaX_syntaxerror(ls, "cannot access upvalue in main", n->str);
+ v.u.index = string_constant(fs->prev, n);
+ }
+ else if (level != 1)
+ luaX_syntaxerror(ls,
+ "upvalue must be global or local to immediately outer scope", n->str);
+ luaK_code1(fs, OP_PUSHUPVALUE, indexupvalue(ls, &v));
}
static void adjust_mult_assign (LexState *ls, int nvars, int nexps) {
FuncState *fs = ls->fs;
int diff = nexps - nvars;
- if (nexps == 0 || !luaK_lastisopen(fs)) { /* list is empty or closed */
- /* push or pop eventual difference between list lengths */
- luaK_adjuststack(fs, diff);
- }
- else { /* list ends in a function call; must correct it */
+ if (nexps > 0 && luaK_lastisopen(fs)) { /* list ends in a function call */
diff--; /* do not count function call itself */
if (diff <= 0) { /* more variables than values? */
- /* function call must provide extra values */
- luaK_setcallreturns(fs, -diff);
+ luaK_setcallreturns(fs, -diff); /* function call provide extra values */
+ diff = 0; /* no more difference */
}
- else { /* more values than variables */
+ else /* more values than variables */
luaK_setcallreturns(fs, 0); /* call should provide no value */
- luaK_adjuststack(fs, diff); /* pop eventual extra values */
- }
}
+ /* push or pop eventual difference between list lengths */
+ luaK_adjuststack(fs, diff);
}
-static void code_args (LexState *ls, int nparams, int dots) {
+static void code_params (LexState *ls, int nparams, int dots) {
FuncState *fs = ls->fs;
- nparams -= dots; /* do not count `...' as a parameter */
adjustlocalvars(ls, nparams);
luaX_checklimit(ls, fs->nlocalvar, MAXPARAMS, "parameters");
- nparams = fs->nlocalvar; /* `self' could be there already */
- fs->f->numparams = nparams;
+ fs->f->numparams = fs->nlocalvar; /* `self' could be there already */
fs->f->is_vararg = dots;
- if (!dots)
- luaK_deltastack(fs, nparams);
- else {
- luaK_deltastack(fs, nparams+1);
+ if (dots)
add_localvar(ls, "arg");
- }
+ luaK_deltastack(fs, fs->nlocalvar); /* count parameters in the stack */
}
@@ -336,21 +321,23 @@ static void leavebreak (FuncState *fs, Breaklabel *bl) {
}
-static Breaklabel *findlabel (FuncState *fs, TString *name) {
+static Breaklabel *findlabel (LexState *ls) {
+ FuncState *fs = ls->fs;
Breaklabel *bl;
+ TString *label = (ls->t.token == TK_NAME) ? ls->t.seminfo.ts : NULL;
for (bl=fs->bl; bl; bl=bl->previous) {
- if (bl->label == name)
+ if (bl->label == label) {
+ if (label) next(ls); /* no errors; can skip optional label */
return bl;
+ }
}
- if (name) /* label not found: choose appropriate error message */
- luaX_syntaxerror(fs->ls, "break not inside given label", name->str);
- else
- luaK_error(fs->ls, "break not inside while or repeat loop");
+ /* label not found */
+ luaK_error(fs->ls, "invalid break");
return NULL; /* to avoid warnings */
}
-static void func_onstack (LexState *ls, FuncState *func) {
+static void pushclosure (LexState *ls, FuncState *func) {
FuncState *fs = ls->fs;
Proto *f = fs->f;
int i;
@@ -363,7 +350,7 @@ static void func_onstack (LexState *ls, FuncState *func) {
}
-static void init_state (LexState *ls, FuncState *fs, TString *source) {
+static void open_func (LexState *ls, FuncState *fs, TString *source) {
Proto *f = luaF_newproto(ls->L);
fs->prev = ls->fs; /* linked list of funcstates */
fs->ls = ls;
@@ -410,13 +397,13 @@ Proto *luaY_parser (lua_State *L, ZIO *z) {
struct LexState lexstate;
struct FuncState funcstate;
luaX_setinput(L, &lexstate, z);
- init_state(&lexstate, &funcstate, luaS_new(L, zname(z)));
+ open_func(&lexstate, &funcstate, luaS_new(L, zname(z)));
next(&lexstate); /* read first token */
chunk(&lexstate);
- if (lexstate.t.token != TK_EOS)
- luaK_error(&lexstate, "<eof> expected");
+ check_condition(&lexstate, (lexstate.t.token == TK_EOS), "<eof> expected");
close_func(&lexstate);
LUA_ASSERT(L, funcstate.prev == NULL, "wrong list end");
+ LUA_ASSERT(L, funcstate.nupvalues == 0, "no upvalues in main");
return funcstate.f;
}
@@ -443,28 +430,16 @@ static int explist1 (LexState *ls) {
}
-static int explist (LexState *ls) {
- /* explist -> [ explist1 ] */
- switch (ls->t.token) {
- case TK_NUMBER: case TK_STRING: case TK_NIL: case '{':
- case TK_FUNCTION: case '(': case TK_NAME: case '%':
- case TK_NOT: case '-': /* first `expr' */
- return explist1(ls);
- default:
- return 0; /* empty list */
- }
-}
-
-
static void funcargs (LexState *ls, int slf) {
FuncState *fs = ls->fs;
int slevel = fs->stacklevel - slf - 1; /* where is func in the stack */
switch (ls->t.token) {
- case '(': { /* funcargs -> '(' explist ')' */
+ case '(': { /* funcargs -> '(' [ explist1 ] ')' */
int line = ls->linenumber;
- int nargs;
+ int nargs = 0;
next(ls);
- nargs = explist(ls);
+ if (ls->t.token != ')') /* arg list not empty? */
+ nargs = explist1(ls);
check_match(ls, ')', '(', line);
#ifdef LUA_COMPAT_ARGRET
if (nargs > 0) /* arg list is not empty? */
@@ -543,7 +518,7 @@ static void var_or_func (LexState *ls, expdesc *v) {
v->u.l.t = v->u.l.f = NO_JUMP;
}
else /* variable name */
- singlevar(ls, str_checkname(ls), v, 0);
+ singlevar(ls, str_checkname(ls), v);
var_or_func_tail(ls, v);
}
@@ -580,7 +555,6 @@ static int recfields (LexState *ls) {
/* recfields -> recfield { ',' recfield } [','] */
FuncState *fs = ls->fs;
int n = 1; /* at least one element */
- int mod_n = 1; /* mod_n == n%RFIELDS_PER_FLUSH */
recfield(ls);
while (ls->t.token == ',') {
next(ls);
@@ -588,13 +562,10 @@ static int recfields (LexState *ls) {
break;
recfield(ls);
n++;
- if (++mod_n == RFIELDS_PER_FLUSH) {
- luaK_code1(fs, OP_SETMAP, RFIELDS_PER_FLUSH-1);
- mod_n = 0;
- }
+ if (n%RFIELDS_PER_FLUSH == 0)
+ luaK_code1(fs, OP_SETMAP, RFIELDS_PER_FLUSH);
}
- if (mod_n)
- luaK_code1(fs, OP_SETMAP, mod_n-1);
+ luaK_code1(fs, OP_SETMAP, n%RFIELDS_PER_FLUSH);
return n;
}
@@ -603,7 +574,6 @@ static int listfields (LexState *ls) {
/* listfields -> exp1 { ',' exp1 } [','] */
FuncState *fs = ls->fs;
int n = 1; /* at least one element */
- int mod_n = 1; /* mod_n == n%LFIELDS_PER_FLUSH */
exp1(ls);
while (ls->t.token == ',') {
next(ls);
@@ -613,13 +583,10 @@ static int listfields (LexState *ls) {
n++;
luaX_checklimit(ls, n/LFIELDS_PER_FLUSH, MAXARG_A,
"`item groups' in a list initializer");
- if (++mod_n == LFIELDS_PER_FLUSH) {
+ if (n%LFIELDS_PER_FLUSH == 0)
luaK_code2(fs, OP_SETLIST, n/LFIELDS_PER_FLUSH - 1, LFIELDS_PER_FLUSH);
- mod_n = 0;
- }
}
- if (mod_n > 0)
- luaK_code2(fs, OP_SETLIST, n/LFIELDS_PER_FLUSH, mod_n);
+ luaK_code2(fs, OP_SETLIST, n/LFIELDS_PER_FLUSH, n%LFIELDS_PER_FLUSH);
return n;
}
@@ -663,18 +630,15 @@ static void constructor (LexState *ls) {
check(ls, '{');
constructor_part(ls, &cd);
nelems = cd.n;
- if (ls->t.token == ';') {
+ if (optional(ls, ';')) {
Constdesc other_cd;
- next(ls);
constructor_part(ls, &other_cd);
- if (cd.k == other_cd.k) /* repeated parts? */
- luaK_error(ls, "invalid constructor syntax");
+ check_condition(ls, (cd.k != other_cd.k), "invalid constructor syntax");
nelems += other_cd.n;
}
check_match(ls, '}', '{', line);
- /* set initial table size */
luaX_checklimit(ls, nelems, MAXARG_U, "elements in a table constructor");
- SETARG_U(fs->f->code[pc], nelems);
+ SETARG_U(fs->f->code[pc], nelems); /* set initial table size */
}
/* }====================================================================== */
@@ -811,6 +775,16 @@ static void expr (LexState *ls, expdesc *v) {
*/
+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;
@@ -822,21 +796,18 @@ static void block (LexState *ls) {
static int assignment (LexState *ls, expdesc *v, int nvars) {
- int left = 0;
+ int left = 0; /* number of values left in the stack after assignment */
luaX_checklimit(ls, nvars, MAXVARSLH, "variables in a multiple assignment");
if (ls->t.token == ',') { /* assignment -> ',' NAME assignment */
expdesc nv;
next(ls);
var_or_func(ls, &nv);
- if (nv.k == VEXP)
- luaK_error(ls, "syntax error");
+ check_condition(ls, (nv.k != VEXP), "syntax error");
left = assignment(ls, &nv, nvars+1);
}
else { /* assignment -> '=' explist1 */
- int nexps;;
- if (ls->t.token != '=')
- error_unexpected(ls);
- next(ls);
+ int nexps;
+ check(ls, '=');
nexps = explist1(ls);
adjust_mult_assign(ls, nvars, nexps);
}
@@ -850,16 +821,22 @@ static int assignment (LexState *ls, expdesc *v, int nvars) {
}
+static void cond (LexState *ls, expdesc *v) {
+ /* cond -> exp */
+ expr(ls, v); /* read condition */
+ luaK_goiftrue(ls->fs, v, 0);
+}
+
+
static void whilestat (LexState *ls, int line) {
- /* whilestat -> WHILE exp1 DO block END */
+ /* whilestat -> WHILE cond DO block END */
FuncState *fs = ls->fs;
int while_init = luaK_getlabel(fs);
expdesc v;
Breaklabel bl;
enterbreak(fs, &bl);
setline_and_next(ls); /* trace WHILE when looping */
- expr(ls, &v); /* read condition */
- luaK_goiftrue(fs, &v, 0);
+ cond(ls, &v);
check(ls, TK_DO);
block(ls);
luaK_patchlist(fs, luaK_jump(fs), while_init);
@@ -870,7 +847,7 @@ static void whilestat (LexState *ls, int line) {
static void repeatstat (LexState *ls, int line) {
- /* repeatstat -> REPEAT block UNTIL exp1 */
+ /* repeatstat -> REPEAT block UNTIL cond */
FuncState *fs = ls->fs;
int repeat_init = luaK_getlabel(fs);
expdesc v;
@@ -879,14 +856,14 @@ static void repeatstat (LexState *ls, int line) {
setline_and_next(ls); /* trace REPEAT when looping */
block(ls);
check_match(ls, TK_UNTIL, TK_REPEAT, line);
- expr(ls, &v);
- luaK_goiftrue(fs, &v, 0);
+ cond(ls, &v);
luaK_patchlist(fs, v.u.l.f, repeat_init);
leavebreak(fs, &bl);
}
static void forbody (LexState *ls, OpCode prepfor, OpCode loopfor) {
+ /* forbody -> DO block END */
FuncState *fs = ls->fs;
int prep = luaK_code1(fs, prepfor, NO_JUMP);
int blockinit = luaK_getlabel(fs);
@@ -898,6 +875,7 @@ static void forbody (LexState *ls, OpCode prepfor, OpCode loopfor) {
static void fornum (LexState *ls, TString *varname) {
+ /* fornum -> NAME = exp1,exp1[,exp1] forbody */
FuncState *fs = ls->fs;
store_localvar(ls, varname, 0);
check(ls, '=');
@@ -910,19 +888,21 @@ static void fornum (LexState *ls, TString *varname) {
luaK_code1(fs, OP_PUSHINT, 1); /* default step */
adjustlocalvars(ls, 1); /* scope for control variables */
add_localvar(ls, "*limit*");
- add_localvar(ls, "*step*");
+ add_localvar(ls, "*count*");
forbody(ls, OP_FORPREP, OP_FORLOOP);
removelocalvars(ls, 3);
}
static void forlist (LexState *ls, TString *indexname) {
+ /* forlist -> NAME,NAME IN exp1 forbody */
TString *valname;
check(ls, ',');
valname = str_checkname(ls);
/* next test is dirty, but avoids `in' being a reserved word */
- if (ls->t.token != TK_NAME || ls->t.seminfo.ts != luaS_new(ls->L, "in"))
- luaK_error(ls, "`in' expected");
+ check_condition(ls,
+ (ls->t.token == TK_NAME && ls->t.seminfo.ts == luaS_new(ls->L, "in")),
+ "`in' expected");
next(ls); /* skip `in' */
exp1(ls); /* table */
add_localvar(ls, "*table*");
@@ -936,8 +916,7 @@ static void forlist (LexState *ls, TString *indexname) {
static void forstat (LexState *ls, int line) {
- /* forstat -> FOR NAME '=' expr1 ',' expr1 [',' expr1] DO block END */
- /* forstat -> FOR NAME1, NAME2 IN expr1 DO block END */
+ /* forstat -> fornum | forlist */
FuncState *fs = ls->fs;
TString *varname;
Breaklabel bl;
@@ -954,11 +933,10 @@ static void forstat (LexState *ls, int line) {
}
-static void test_and_block (LexState *ls, expdesc *v) {
- /* test_and_block -> [IF | ELSEIF] cond THEN block */
+static void test_then_block (LexState *ls, expdesc *v) {
+ /* test_then_block -> [IF | ELSEIF] cond THEN block */
setline_and_next(ls); /* skip IF or ELSEIF */
- expr(ls, v); /* cond */
- luaK_goiftrue(ls->fs, v, 0);
+ cond(ls, v);
setline(ls); /* to trace the THEN */
check(ls, TK_THEN);
block(ls); /* `then' part */
@@ -970,11 +948,11 @@ static void ifstat (LexState *ls, int line) {
FuncState *fs = ls->fs;
expdesc v;
int escapelist = NO_JUMP;
- test_and_block(ls, &v); /* IF cond THEN block */
+ test_then_block(ls, &v); /* IF cond THEN block */
while (ls->t.token == TK_ELSEIF) {
luaK_concat(fs, &escapelist, luaK_jump(fs));
luaK_patchlist(fs, v.u.l.f, luaK_getlabel(fs));
- test_and_block(ls, &v); /* ELSEIF cond THEN block */
+ test_then_block(ls, &v); /* ELSEIF cond THEN block */
}
if (ls->t.token == TK_ELSE) {
luaK_concat(fs, &escapelist, luaK_jump(fs));
@@ -989,36 +967,18 @@ static void ifstat (LexState *ls, int line) {
}
-static int localnamelist (LexState *ls) {
- /* localnamelist -> NAME {',' NAME} */
- int i = 1;
- store_localvar(ls, str_checkname(ls), 0);
- while (ls->t.token == ',') {
- next(ls);
- store_localvar(ls, str_checkname(ls), i++);
- }
- return i;
-}
-
-
-static int decinit (LexState *ls) {
- /* decinit -> ['=' explist1] */
- if (ls->t.token == '=') {
- next(ls);
- return explist1(ls);
- }
- else
- return 0; /* no initializations */
-}
-
-
static void localstat (LexState *ls) {
- /* stat -> LOCAL localnamelist decinit */
- int nvars;
+ /* stat -> LOCAL NAME {',' NAME} ['=' explist1] */
+ int nvars = 0;
int nexps;
- setline_and_next(ls); /* skip LOCAL */
- nvars = localnamelist(ls);
- nexps = decinit(ls);
+ do {
+ setline_and_next(ls); /* skip LOCAL or ',' */
+ store_localvar(ls, str_checkname(ls), nvars++);
+ } while (ls->t.token == ',');
+ if (optional(ls, '='))
+ nexps = explist1(ls);
+ else
+ nexps = 0;
adjustlocalvars(ls, nvars);
adjust_mult_assign(ls, nvars, nexps);
}
@@ -1027,7 +987,7 @@ static void localstat (LexState *ls) {
static int funcname (LexState *ls, expdesc *v) {
/* funcname -> NAME [':' NAME | '.' NAME] */
int needself = 0;
- singlevar(ls, str_checkname(ls), v, 0);
+ singlevar(ls, str_checkname(ls), v);
if (ls->t.token == ':' || ls->t.token == '.') {
needself = (ls->t.token == ':');
next(ls);
@@ -1043,8 +1003,8 @@ static void funcstat (LexState *ls, int line) {
/* funcstat -> FUNCTION funcname body */
int needself;
expdesc v;
- if (ls->fs->prev) /* inside other function? */
- luaK_error(ls, "cannot nest this kind of function declaration");
+ check_condition(ls, (ls->fs->prev == NULL),
+ "cannot nest this kind of function declaration");
setline_and_next(ls); /* skip FUNCTION */
needself = funcname(ls, &v);
body(ls, needself, line);
@@ -1059,8 +1019,7 @@ static void namestat (LexState *ls) {
setline(ls);
var_or_func(ls, &v);
if (v.k == VEXP) { /* stat -> func */
- if (!luaK_lastisopen(fs)) /* is just an upvalue? */
- luaK_error(ls, "syntax error");
+ check_condition(ls, luaK_lastisopen(fs), "syntax error"); /* an upvalue? */
luaK_setcallreturns(fs, 0); /* call statement uses no results */
}
else { /* stat -> ['%'] NAME assignment */
@@ -1074,7 +1033,8 @@ static void retstat (LexState *ls) {
/* stat -> RETURN explist */
FuncState *fs = ls->fs;
setline_and_next(ls); /* skip RETURN */
- explist(ls);
+ if (!block_follow(ls->t.token))
+ explist1(ls); /* optional return values */
luaK_code1(fs, OP_RETURN, ls->fs->nlocalvar);
fs->stacklevel = fs->nlocalvar; /* removes all temp values */
}
@@ -1086,7 +1046,7 @@ static void breakstat (LexState *ls) {
Breaklabel *bl;
int currentlevel = fs->stacklevel;
setline_and_next(ls); /* skip BREAK */
- bl = findlabel(fs, optionalname(ls));
+ bl = findlabel(ls);
luaK_adjuststack(fs, currentlevel - bl->stacklevel);
luaK_concat(fs, &bl->breaklist, luaK_jump(fs));
fs->stacklevel = currentlevel;
@@ -1098,66 +1058,48 @@ static int stat (LexState *ls) {
switch (ls->t.token) {
case TK_IF: { /* stat -> ifstat */
ifstat(ls, line);
- return 1;
+ return 0;
}
case TK_WHILE: { /* stat -> whilestat */
whilestat(ls, line);
- return 1;
+ return 0;
}
case TK_DO: { /* stat -> DO block END */
setline_and_next(ls); /* skip DO */
block(ls);
check_END(ls, TK_DO, line);
- return 1;
+ return 0;
}
case TK_FOR: { /* stat -> forstat */
forstat(ls, line);
- return 1;
+ return 0;
}
case TK_REPEAT: { /* stat -> repeatstat */
repeatstat(ls, line);
- return 1;
+ return 0;
}
case TK_FUNCTION: { /* stat -> funcstat */
funcstat(ls, line);
- return 1;
+ return 0;
}
case TK_LOCAL: { /* stat -> localstat */
localstat(ls);
- return 1;
+ return 0;
}
case TK_NAME: case '%': { /* stat -> namestat */
namestat(ls);
- return 1;
+ return 0;
}
case TK_RETURN: { /* stat -> retstat */
retstat(ls);
- return 2; /* must be last statement */
+ return 1; /* must be last statement */
}
case TK_BREAK: { /* stat -> breakstat */
breakstat(ls);
- return 2; /* must be last statement */
+ return 1; /* must be last statement */
}
default: {
- return 0; /* no statement */
- }
- }
-}
-
-
-static int param (LexState *ls, int n) {
- /* param -> NAME | DOTS */
- switch (ls->t.token) {
- case TK_DOTS: {
- next(ls);
- return 1;
- }
- case TK_NAME: {
- store_localvar(ls, str_checkname(ls), n);
- return 0;
- }
- default: {
- luaK_error(ls, "<name> or `...' expected");
+ luaK_error(ls, "<statement> expected");
return 0; /* to avoid warnings */
}
}
@@ -1169,22 +1111,22 @@ static void parlist (LexState *ls) {
int nparams = 0;
int dots = 0;
if (ls->t.token != ')') { /* is `parlist' not empty? */
- dots = param(ls, nparams);
- nparams++;
- while (ls->t.token == ',' && !dots) {
- next(ls);
- dots = param(ls, nparams);
- nparams++;
- }
+ do {
+ switch (ls->t.token) {
+ case TK_DOTS: next(ls); dots = 1; break;
+ case TK_NAME: store_localvar(ls, str_checkname(ls), nparams++); break;
+ default: luaK_error(ls, "<name> or `...' expected");
+ }
+ } while (!dots && optional(ls, ','));
}
- code_args(ls, nparams, dots);
+ code_params(ls, nparams, dots);
}
static void body (LexState *ls, int needself, int line) {
/* body -> '(' parlist ')' chunk END */
FuncState new_fs;
- init_state(ls, &new_fs, ls->fs->f->source);
+ open_func(ls, &new_fs, ls->fs->f->source);
new_fs.f->lineDefined = line;
check(ls, '(');
if (needself)
@@ -1194,40 +1136,40 @@ static void body (LexState *ls, int needself, int line) {
chunk(ls);
check_END(ls, TK_FUNCTION, line);
close_func(ls);
- func_onstack(ls, &new_fs);
+ pushclosure(ls, &new_fs);
}
/* }====================================================================== */
-static void label (LexState *ls, Breaklabel *bl) {
+static TString *optional_label (LexState *ls) {
/* label -> [ '|' NAME '|' ] */
if (optional(ls, '|')) {
- enterbreak(ls->fs, bl);
- bl->label = str_checkname(ls);
+ TString *l = str_checkname(ls);
check(ls, '|');
+ return l;
}
else
- bl->label = NULL; /* there is no label */
+ return NULL; /* there is no label */
}
static void chunk (LexState *ls) {
/* chunk -> { [label] stat [';'] } */
- Breaklabel bl;
- int a;
- do {
- label(ls, &bl);
- a = stat(ls);
- if (a != 0)
- optional(ls, ';');
- else if (bl.label)
- luaK_error(ls, "label without a statement");
+ int islast = 0;
+ while (!islast && !block_follow(ls->t.token)) {
+ Breaklabel bl;
+ TString *l = optional_label(ls);
+ if (l) {
+ enterbreak(ls->fs, &bl);
+ bl.label = l;
+ }
+ islast = stat(ls);
+ optional(ls, ';');
LUA_ASSERT(ls->L, ls->fs->stacklevel == ls->fs->nlocalvar,
"stack size != # local vars");
- if (bl.label)
- leavebreak(ls->fs, &bl);
- } while (a == 1);
+ if (l) leavebreak(ls->fs, &bl);
+ }
}
diff --git a/lvm.c b/lvm.c
@@ -1,5 +1,5 @@
/*
-** $Id: lvm.c,v 1.109 2000/05/25 19:02:21 roberto Exp roberto $
+** $Id: lvm.c,v 1.110 2000/05/30 19:00:31 roberto Exp roberto $
** Lua virtual machine
** See Copyright Notice in lua.h
*/
@@ -483,13 +483,13 @@ StkId luaV_execute (lua_State *L, const Closure *cl, StkId base) {
case OP_SETMAP: {
int n = GETARG_U(i);
- StkId finaltop = top-2*(n+1);
+ StkId finaltop = top-2*n;
Hash *arr = avalue(finaltop-1);
L->top = finaltop; /* final value of `top' (in case of errors) */
- do {
+ for (; n; n--) {
luaH_set(L, arr, top-2, top-1);
top-=2;
- } while (n--);
+ }
break;
}
@@ -625,23 +625,22 @@ StkId luaV_execute (lua_State *L, const Closure *cl, StkId base) {
lua_error(L, "`for' limit must be a number");
if (tonumber(top-3))
lua_error(L, "`for' initial value must be a number");
+ /* number of steps */
+ nvalue(top-2) = (nvalue(top-2)-nvalue(top-3))/nvalue(top-1);
nvalue(top-3) -= nvalue(top-1); /* to be undone by first FORLOOP */
pc += GETARG_S(i);
break;
case OP_FORLOOP: {
- Number step = nvalue(top-1);
- Number limit = nvalue(top-2);
- Number index;
LUA_ASSERT(L, ttype(top-1) == TAG_NUMBER, "invalid step");
- LUA_ASSERT(L, ttype(top-2) == TAG_NUMBER, "invalid limit");
- if (ttype(top-3) != TAG_NUMBER)
- lua_error(L, "`for' index must be a number");
- index = nvalue(top-3)+step;
- if ((step>0) ? index>limit : index<limit)
+ LUA_ASSERT(L, ttype(top-2) == TAG_NUMBER, "invalid count");
+ if (nvalue(top-2) < 0)
top -= 3; /* end loop: remove control variables */
else {
- nvalue(top-3) = index;
+ nvalue(top-2)--; /* decrement count */
+ if (ttype(top-3) != TAG_NUMBER)
+ lua_error(L, "`for' index must be a number");
+ nvalue(top-3) += nvalue(top-1); /* increment index */
pc += GETARG_S(i);
}
break;
