diff options
Diffstat (limited to 'src/lvm.c')
| -rw-r--r-- | src/lvm.c | 181 |
1 files changed, 125 insertions, 56 deletions
@@ -1,10 +1,11 @@ /* -** $Id: lvm.c,v 2.175 2013/06/20 15:02:49 roberto Exp $ +** $Id: lvm.c,v 2.190 2014/03/15 12:29:48 roberto Exp $ ** Lua virtual machine ** See Copyright Notice in lua.h */ +#include <limits.h> #include <stdio.h> #include <stdlib.h> #include <string.h> @@ -29,7 +30,7 @@ /* limit for table tag-method chains (to avoid loops) */ -#define MAXTAGLOOP 100 +#define MAXTAGLOOP 2000 /* maximum length of the conversion of a number to a string */ @@ -52,17 +53,9 @@ int luaV_tostring (lua_State *L, StkId obj) { return 0; else { char buff[MAXNUMBER2STR]; - size_t len; - if (ttisinteger(obj)) - len = lua_integer2str(buff, ivalue(obj)); - else { - len = lua_number2str(buff, fltvalue(obj)); - if (strspn(buff, "-0123456789") == len) { /* look like an integer? */ - buff[len++] = '.'; /* add a '.0' */ - buff[len++] = '0'; - buff[len] = '\0'; - } - } + size_t len = (ttisinteger(obj)) + ? lua_integer2str(buff, ivalue(obj)) + : lua_number2str(buff, fltvalue(obj)); setsvalue2s(L, obj, luaS_newlstr(L, buff, len)); return 1; } @@ -73,7 +66,7 @@ int luaV_tostring (lua_State *L, StkId obj) { ** Check whether a float number is within the range of a lua_Integer. ** (The comparisons are tricky because of rounding, which can or ** not occur depending on the relative sizes of floats and integers.) -** This function is called only when 'n' has an integer value. +** This function should be called only when 'n' has an integral value. */ int luaV_numtointeger (lua_Number n, lua_Integer *p) { if (cast_num(MIN_INTEGER) <= n && n < (MAX_INTEGER + cast_num(1))) { @@ -121,7 +114,7 @@ void luaV_gettable (lua_State *L, const TValue *t, TValue *key, StkId val) { } t = tm; /* else repeat with 'tm' */ } - luaG_runerror(L, "loop in gettable"); + luaG_runerror(L, "gettable chain too long; possible loop"); } @@ -145,7 +138,7 @@ void luaV_settable (lua_State *L, const TValue *t, TValue *key, StkId val) { /* no metamethod and (now) there is an entry with given key */ setobj2t(L, oldval, val); /* assign new value to that entry */ invalidateTMcache(h); - luaC_barrierback(L, obj2gco(h), val); + luaC_barrierback(L, h, val); return; } /* else will try the metamethod */ @@ -160,7 +153,7 @@ void luaV_settable (lua_State *L, const TValue *t, TValue *key, StkId val) { } t = tm; /* else repeat with 'tm' */ } - luaG_runerror(L, "loop in settable"); + luaG_runerror(L, "settable chain too long; possible loop"); } @@ -192,7 +185,7 @@ int luaV_lessthan (lua_State *L, const TValue *l, const TValue *r) { if (ttisinteger(l) && ttisinteger(r)) return (ivalue(l) < ivalue(r)); else if (tonumber(l, &nl) && tonumber(r, &nr)) - return luai_numlt(L, nl, nr); + return luai_numlt(nl, nr); else if (ttisstring(l) && ttisstring(r)) return l_strcmp(rawtsvalue(l), rawtsvalue(r)) < 0; else if ((res = luaT_callorderTM(L, l, r, TM_LT)) < 0) @@ -207,7 +200,7 @@ int luaV_lessequal (lua_State *L, const TValue *l, const TValue *r) { if (ttisinteger(l) && ttisinteger(r)) return (ivalue(l) <= ivalue(r)); else if (tonumber(l, &nl) && tonumber(r, &nr)) - return luai_numle(L, nl, nr); + return luai_numle(nl, nr); else if (ttisstring(l) && ttisstring(r)) return l_strcmp(rawtsvalue(l), rawtsvalue(r)) <= 0; else if ((res = luaT_callorderTM(L, l, r, TM_LE)) >= 0) /* first try `le' */ @@ -229,7 +222,7 @@ int luaV_equalobj (lua_State *L, const TValue *t1, const TValue *t2) { else { /* two numbers with different variants */ lua_Number n1, n2; lua_assert(ttisnumber(t1) && ttisnumber(t2)); - (void)tonumber(t1, &n1); (void)tonumber(t2, &n2); + cast_void(tonumber(t1, &n1)); cast_void(tonumber(t2, &n2)); return luai_numeq(n1, n2); } } @@ -272,7 +265,7 @@ void luaV_concat (lua_State *L, int total) { if (!(ttisstring(top-2) || ttisnumber(top-2)) || !tostring(L, top-1)) luaT_trybinTM(L, top-2, top-1, top-2, TM_CONCAT); else if (tsvalue(top-1)->len == 0) /* second operand is empty? */ - (void)tostring(L, top - 2); /* result is first operand */ + cast_void(tostring(L, top - 2)); /* result is first operand */ else if (ttisstring(top-2) && tsvalue(top-2)->len == 0) { setobjs2s(L, top - 2, top - 1); /* result is second op. */ } @@ -333,8 +326,7 @@ lua_Integer luaV_div (lua_State *L, lua_Integer x, lua_Integer y) { if (cast_unsigned(y) + 1 <= 1U) { /* special cases: -1 or 0 */ if (y == 0) luaG_runerror(L, "attempt to divide by zero"); - else /* -1 */ - return -x; /* avoid overflow with 0x80000... */ + return intop(-, 0, x); /* y==-1; avoid overflow with 0x80000...//-1 */ } else { lua_Integer d = x / y; /* perform division */ @@ -350,8 +342,7 @@ lua_Integer luaV_mod (lua_State *L, lua_Integer x, lua_Integer y) { if (cast_unsigned(y) + 1 <= 1U) { /* special cases: -1 or 0 */ if (y == 0) luaG_runerror(L, "attempt to perform 'n%%0'"); - else /* -1 */ - return 0; /* avoid overflow with 0x80000... */ + return 0; /* y==-1; avoid overflow with 0x80000...%-1 */ } else { lua_Integer r = x % y; @@ -363,16 +354,36 @@ lua_Integer luaV_mod (lua_State *L, lua_Integer x, lua_Integer y) { } -lua_Integer luaV_pow (lua_Integer x, lua_Integer y) { - lua_Integer r = 1; - lua_assert(y >= 0); - if (y == 0) return r; - for (; y > 1; y >>= 1) { - if (y & 1) r = intop(*, r, x); - x = intop(*, x, x); +lua_Integer luaV_pow (lua_State *L, lua_Integer x, lua_Integer y) { + if (y <= 0) { /* special cases: 0 or negative exponent */ + if (y < 0) + luaG_runerror(L, "integer exponentiation with negative exponent"); + return 1; /* x^0 == 1 */ + } + else { + lua_Integer r = 1; + for (; y > 1; y >>= 1) { + if (y & 1) r = intop(*, r, x); + x = intop(*, x, x); + } + r = intop(*, r, x); + return r; + } +} + + +/* number of bits in an integer */ +#define NBITS cast_int(sizeof(lua_Integer) * CHAR_BIT) + +LUAI_FUNC lua_Integer luaV_shiftl (lua_Integer x, lua_Integer y) { + if (y < 0) { /* shift right? */ + if (y <= -NBITS) return 0; + else return cast_integer(cast_unsigned(x) >> (-y)); + } + else { /* shift left */ + if (y >= NBITS) return 0; + else return x << y; } - r = intop(*, r, x); - return r; } @@ -399,9 +410,9 @@ static Closure *getcached (Proto *p, UpVal **encup, StkId base) { /* ** create a new Lua closure, push it in the stack, and initialize -** its upvalues. Note that the call to 'luaC_barrierproto' must come -** before the assignment to 'p->cache', as the function needs the -** original value of that field. +** its upvalues. Note that the closure is not cached if prototype is +** already black (which means that 'cache' was already cleared by the +** GC). */ static void pushclosure (lua_State *L, Proto *p, UpVal **encup, StkId base, StkId ra) { @@ -416,9 +427,11 @@ static void pushclosure (lua_State *L, Proto *p, UpVal **encup, StkId base, ncl->l.upvals[i] = luaF_findupval(L, base + uv[i].idx); else /* get upvalue from enclosing function */ ncl->l.upvals[i] = encup[uv[i].idx]; + ncl->l.upvals[i]->refcount++; + /* new closure is white, so we do not need a barrier here */ } - luaC_barrierproto(L, p, ncl); - p->cache = ncl; /* save it on cache for reuse */ + if (!isblack(obj2gco(p))) /* cache will not break GC invariant? */ + p->cache = ncl; /* save it on cache for reuse */ } @@ -432,7 +445,9 @@ void luaV_finishOp (lua_State *L) { OpCode op = GET_OPCODE(inst); switch (op) { /* finish its execution */ case OP_ADD: case OP_SUB: case OP_MUL: case OP_DIV: case OP_IDIV: - case OP_MOD: case OP_POW: case OP_UNM: case OP_LEN: + case OP_BAND: case OP_BOR: case OP_BXOR: case OP_SHL: case OP_SHR: + case OP_MOD: case OP_POW: + case OP_UNM: case OP_BNOT: case OP_LEN: case OP_GETTABUP: case OP_GETTABLE: case OP_SELF: { setobjs2s(L, base + GETARG_A(inst), --L->top); break; @@ -590,7 +605,7 @@ void luaV_execute (lua_State *L) { vmcase(OP_SETUPVAL, UpVal *uv = cl->upvals[GETARG_B(i)]; setobj(L, uv->v, ra); - luaC_barrier(L, uv, ra); + luaC_upvalbarrier(L, uv); ) vmcase(OP_SETTABLE, Protect(luaV_settable(L, ra, RKB(i), RKC(i))); @@ -666,6 +681,51 @@ void luaV_execute (lua_State *L) { } else { Protect(luaT_trybinTM(L, rb, rc, ra, TM_IDIV)); } ) + vmcase(OP_BAND, + TValue *rb = RKB(i); + TValue *rc = RKC(i); + lua_Integer ib; lua_Integer ic; + if (tointeger(rb, &ib) && tointeger(rc, &ic)) { + setivalue(ra, intop(&, ib, ic)); + } + else { Protect(luaT_trybinTM(L, rb, rc, ra, TM_BAND)); } + ) + vmcase(OP_BOR, + TValue *rb = RKB(i); + TValue *rc = RKC(i); + lua_Integer ib; lua_Integer ic; + if (tointeger(rb, &ib) && tointeger(rc, &ic)) { + setivalue(ra, intop(|, ib, ic)); + } + else { Protect(luaT_trybinTM(L, rb, rc, ra, TM_BOR)); } + ) + vmcase(OP_BXOR, + TValue *rb = RKB(i); + TValue *rc = RKC(i); + lua_Integer ib; lua_Integer ic; + if (tointeger(rb, &ib) && tointeger(rc, &ic)) { + setivalue(ra, intop(^, ib, ic)); + } + else { Protect(luaT_trybinTM(L, rb, rc, ra, TM_BXOR)); } + ) + vmcase(OP_SHL, + TValue *rb = RKB(i); + TValue *rc = RKC(i); + lua_Integer ib; lua_Integer ic; + if (tointeger(rb, &ib) && tointeger(rc, &ic)) { + setivalue(ra, luaV_shiftl(ib, ic)); + } + else { Protect(luaT_trybinTM(L, rb, rc, ra, TM_SHL)); } + ) + vmcase(OP_SHR, + TValue *rb = RKB(i); + TValue *rc = RKC(i); + lua_Integer ib; lua_Integer ic; + if (tointeger(rb, &ib) && tointeger(rc, &ic)) { + setivalue(ra, luaV_shiftl(ib, -ic)); + } + else { Protect(luaT_trybinTM(L, rb, rc, ra, TM_SHR)); } + ) vmcase(OP_MOD, TValue *rb = RKB(i); TValue *rc = RKC(i); @@ -683,11 +743,9 @@ void luaV_execute (lua_State *L) { TValue *rb = RKB(i); TValue *rc = RKC(i); lua_Number nb; lua_Number nc; - lua_Integer ic; - if (ttisinteger(rb) && ttisinteger(rc) && - (ic = ivalue(rc)) >= 0) { - lua_Integer ib = ivalue(rb); - setivalue(ra, luaV_pow(ib, ic)); + if (ttisinteger(rb) && ttisinteger(rc)) { + lua_Integer ib = ivalue(rb); lua_Integer ic = ivalue(rc); + setivalue(ra, luaV_pow(L, ib, ic)); } else if (tonumber(rb, &nb) && tonumber(rc, &nc)) { setnvalue(ra, luai_numpow(L, nb, nc)); @@ -699,7 +757,7 @@ void luaV_execute (lua_State *L) { lua_Number nb; if (ttisinteger(rb)) { lua_Integer ib = ivalue(rb); - setivalue(ra, -ib); + setivalue(ra, intop(-, 0, ib)); } else if (tonumber(rb, &nb)) { setnvalue(ra, luai_numunm(L, nb)); @@ -708,6 +766,16 @@ void luaV_execute (lua_State *L) { Protect(luaT_trybinTM(L, rb, rb, ra, TM_UNM)); } ) + vmcase(OP_BNOT, + TValue *rb = RB(i); + lua_Integer ib; + if (tointeger(rb, &ib)) { + setivalue(ra, intop(^, cast_integer(-1), ib)); + } + else { + Protect(luaT_trybinTM(L, rb, rb, ra, TM_BNOT)); + } + ) vmcase(OP_NOT, TValue *rb = RB(i); int res = l_isfalse(rb); /* next assignment may change this value */ @@ -831,7 +899,7 @@ void luaV_execute (lua_State *L) { } ) vmcase(OP_FORLOOP, - if (ttisinteger(ra)) { /* integer count? */ + if (ttisinteger(ra)) { /* integer loop? */ lua_Integer step = ivalue(ra + 2); lua_Integer idx = ivalue(ra) + step; /* increment index */ lua_Integer limit = ivalue(ra + 1); @@ -841,12 +909,12 @@ void luaV_execute (lua_State *L) { setivalue(ra + 3, idx); /* ...and external index */ } } - else { /* floating count */ + else { /* floating loop */ lua_Number step = fltvalue(ra + 2); lua_Number idx = luai_numadd(L, fltvalue(ra), step); /* inc. index */ lua_Number limit = fltvalue(ra + 1); - if (luai_numlt(L, 0, step) ? luai_numle(L, idx, limit) - : luai_numle(L, limit, idx)) { + if (luai_numlt(0, step) ? luai_numle(idx, limit) + : luai_numle(limit, idx)) { ci->u.l.savedpc += GETARG_sBx(i); /* jump back */ setnvalue(ra, idx); /* update internal index... */ setnvalue(ra + 3, idx); /* ...and external index */ @@ -857,10 +925,11 @@ void luaV_execute (lua_State *L) { TValue *init = ra; TValue *plimit = ra + 1; TValue *pstep = ra + 2; - if (ttisinteger(ra) && ttisinteger(ra + 1) && ttisinteger(ra + 2)) { - setivalue(ra, ivalue(ra) - ivalue(pstep)); + if (ttisinteger(init) && ttisinteger(plimit) && ttisinteger(pstep)) { + /* all values are integer */ + setivalue(init, ivalue(init) - ivalue(pstep)); } - else { /* try with floats */ + else { /* try making all values floats */ lua_Number ninit; lua_Number nlimit; lua_Number nstep; if (!tonumber(plimit, &nlimit)) luaG_runerror(L, LUA_QL("for") " limit must be a number"); @@ -870,7 +939,7 @@ void luaV_execute (lua_State *L) { setnvalue(pstep, nstep); if (!tonumber(init, &ninit)) luaG_runerror(L, LUA_QL("for") " initial value must be a number"); - setnvalue(ra, luai_numsub(L, ninit, nstep)); + setnvalue(init, luai_numsub(L, ninit, nstep)); } ci->u.l.savedpc += GETARG_sBx(i); ) @@ -912,7 +981,7 @@ void luaV_execute (lua_State *L) { for (; n > 0; n--) { TValue *val = ra+n; luaH_setint(L, h, last--, val); - luaC_barrierback(L, obj2gco(h), val); + luaC_barrierback(L, h, val); } L->top = ci->top; /* correct top (in case of previous open call) */ ) |