nik/lush
1
1
Fork 0
Code Issues Pull Requests Actions Packages Projects Releases Wiki Activity

new function 'luaV_flttointeger' to convert floats to integers (without

Browse Source 
string coercions) + string operands to bitwise operations handled
by string metamethods
This commit is contained in:
Roberto Ierusalimschy
2017-11-08 12:50:23 -02:00
parent c3e5946fb2
commit 26679ea35b
8 changed files with 126 additions and 48 deletions
Download Patch File Download Diff File Expand all files Collapse all files

60
lvm.c
View File

@@ -1,5 +1,5 @@
/*
** $Id: lvm.c,v 2.306 2017/11/07 13:25:26 roberto Exp roberto $
** $Id: lvm.c,v 2.307 2017/11/07 17:20:42 roberto Exp roberto $
** Lua virtual machine
** See Copyright Notice in lua.h
*/
@@ -74,7 +74,7 @@ int luaV_tonumber_ (const TValue *obj, lua_Number *n) {
*n = cast_num(ivalue(obj));
return 1;
}
else if (cvt2num(obj) && /* string convertible to number? */
else if (cvt2num(obj) && /* string coercible to number? */
luaO_str2num(svalue(obj), &v) == vslen(obj) + 1) {
*n = nvalue(&v); /* convert result of 'luaO_str2num' to a float */
return 1;
@@ -85,15 +85,15 @@ int luaV_tonumber_ (const TValue *obj, lua_Number *n) {
/*
** try to convert a value to an integer, rounding according to 'mode':
** try to convert a float to an integer, rounding according to 'mode':
** mode == 0: accepts only integral values
** mode == 1: takes the floor of the number
** mode == 2: takes the ceil of the number
*/
int luaV_tointeger (const TValue *obj, lua_Integer *p, int mode) {
TValue v;
again:
if (ttisfloat(obj)) {
int luaV_flttointeger (const TValue *obj, lua_Integer *p, int mode) {
if (!ttisfloat(obj))
return 0;
else {
lua_Number n = fltvalue(obj);
lua_Number f = l_floor(n);
if (n != f) { /* not an integral value? */
@@ -103,16 +103,23 @@ int luaV_tointeger (const TValue *obj, lua_Integer *p, int mode) {
}
return lua_numbertointeger(f, p);
}
else if (ttisinteger(obj)) {
}
/*
** try to convert a value to an integer. ("Fast track" is handled
** by macro 'tointeger'.)
*/
int luaV_tointeger (const TValue *obj, lua_Integer *p, int mode) {
TValue v;
if (cvt2num(obj) && luaO_str2num(svalue(obj), &v) == vslen(obj) + 1)
obj = &v; /* change string to its corresponding number */
if (ttisinteger(obj)) {
*p = ivalue(obj);
return 1;
}
else if (cvt2num(obj) &&
luaO_str2num(svalue(obj), &v) == vslen(obj) + 1) {
obj = &v;
goto again; /* convert result from 'luaO_str2num' to an integer */
}
return 0; /* conversion failed */
else
return luaV_flttointeger(obj, p, mode);
}
@@ -120,9 +127,9 @@ int luaV_tointeger (const TValue *obj, lua_Integer *p, int mode) {
** Try to convert a 'for' limit to an integer, preserving the semantics
** of the loop. (The following explanation assumes a non-negative step;
** it is valid for negative steps mutatis mutandis.)
** If the limit can be converted to an integer, rounding down, that is
** it.
** Otherwise, check whether the limit can be converted to a number. If
** If the limit is an integer or can be converted to an integer,
** rounding down, that is it.
** Otherwise, check whether the limit can be converted to a float. If
** the number is too large, it is OK to set the limit as LUA_MAXINTEGER,
** which means no limit. If the number is too negative, the loop
** should not run, because any initial integer value is larger than the
@@ -133,7 +140,10 @@ int luaV_tointeger (const TValue *obj, lua_Integer *p, int mode) {
static int forlimit (const TValue *obj, lua_Integer *p, lua_Integer step,
int *stopnow) {
*stopnow = 0; /* usually, let loops run */
if (!luaV_tointeger(obj, p, (step < 0 ? 2 : 1))) { /* not fit in integer? */
if (ttisinteger(obj))
*p = ivalue(obj);
else if (!luaV_tointeger(obj, p, (step < 0 ? 2 : 1))) {
/* not coercible to in integer */
lua_Number n; /* try to convert to float */
if (!tonumber(obj, &n)) /* cannot convert to float? */
return 0; /* not a number */
@@ -411,7 +421,7 @@ int luaV_equalobj (lua_State *L, const TValue *t1, const TValue *t2) {
return 0; /* only numbers can be equal with different variants */
else { /* two numbers with different variants */
lua_Integer i1, i2; /* compare them as integers */
return (tointeger(t1, &i1) && tointeger(t2, &i2) && i1 == i2);
return (tointegerns(t1, &i1) && tointegerns(t2, &i2) && i1 == i2);
}
}
/* values have same type and same variant */
@@ -1144,7 +1154,7 @@ void luaV_execute (lua_State *L) {
TValue *rb = vRB(i);
TValue *rc = vRC(i);
lua_Integer ib; lua_Integer ic;
if (tointeger(rb, &ib) && tointeger(rc, &ic)) {
if (tointegerns(rb, &ib) && tointegerns(rc, &ic)) {
setivalue(s2v(ra), intop(&, ib, ic));
}
else { Protect(luaT_trybinTM(L, rb, rc, ra, TM_BAND)); }
@@ -1154,7 +1164,7 @@ void luaV_execute (lua_State *L) {
TValue *rb = vRB(i);
TValue *rc = vRC(i);
lua_Integer ib; lua_Integer ic;
if (tointeger(rb, &ib) && tointeger(rc, &ic)) {
if (tointegerns(rb, &ib) && tointegerns(rc, &ic)) {
setivalue(s2v(ra), intop(|, ib, ic));
}
else { Protect(luaT_trybinTM(L, rb, rc, ra, TM_BOR)); }
@@ -1164,7 +1174,7 @@ void luaV_execute (lua_State *L) {
TValue *rb = vRB(i);
TValue *rc = vRC(i);
lua_Integer ib; lua_Integer ic;
if (tointeger(rb, &ib) && tointeger(rc, &ic)) {
if (tointegerns(rb, &ib) && tointegerns(rc, &ic)) {
setivalue(s2v(ra), intop(^, ib, ic));
}
else { Protect(luaT_trybinTM(L, rb, rc, ra, TM_BXOR)); }
@@ -1174,7 +1184,7 @@ void luaV_execute (lua_State *L) {
TValue *rb = vRB(i);
TValue *rc = vRC(i);
lua_Integer ib; lua_Integer ic;
if (tointeger(rb, &ib) && tointeger(rc, &ic)) {
if (tointegerns(rb, &ib) && tointegerns(rc, &ic)) {
setivalue(s2v(ra), luaV_shiftl(ib, ic));
}
else { Protect(luaT_trybinTM(L, rb, rc, ra, TM_SHL)); }
@@ -1184,7 +1194,7 @@ void luaV_execute (lua_State *L) {
TValue *rb = vRB(i);
TValue *rc = vRC(i);
lua_Integer ib; lua_Integer ic;
if (tointeger(rb, &ib) && tointeger(rc, &ic)) {
if (tointegerns(rb, &ib) && tointegerns(rc, &ic)) {
setivalue(s2v(ra), luaV_shiftl(ib, -ic));
}
else { Protect(luaT_trybinTM(L, rb, rc, ra, TM_SHR)); }
@@ -1248,7 +1258,7 @@ void luaV_execute (lua_State *L) {
vmcase(OP_BNOT) {
TValue *rb = vRB(i);
lua_Integer ib;
if (tointeger(rb, &ib)) {
if (tointegerns(rb, &ib)) {
setivalue(s2v(ra), intop(^, ~l_castS2U(0), ib));
}
else {