diff options
Diffstat (limited to 'erts/emulator/beam/bif.c')
-rw-r--r-- | erts/emulator/beam/bif.c | 205 |
1 files changed, 17 insertions, 188 deletions
diff --git a/erts/emulator/beam/bif.c b/erts/emulator/beam/bif.c index 7e8eb44680..e116b10b95 100644 --- a/erts/emulator/beam/bif.c +++ b/erts/emulator/beam/bif.c @@ -2917,175 +2917,20 @@ BIF_RETTYPE integer_to_list_1(BIF_ALIST_1) /**********************************************************************/ -/* convert a list of ascii ascii integer value to an integer */ - - -#define LTI_BAD_STRUCTURE 0 -#define LTI_NO_INTEGER 1 -#define LTI_SOME_INTEGER 2 -#define LTI_ALL_INTEGER 3 - -static int do_list_to_integer(Process *p, Eterm orig_list, - Eterm *integer, Eterm *rest) -{ - Sint i = 0; - Uint ui = 0; - int skip = 0; - int neg = 0; - Sint n = 0; - int m; - int lg2; - Eterm res; - Eterm* hp; - Eterm *hp_end; - Eterm lst = orig_list; - Eterm tail = lst; - int error_res = LTI_BAD_STRUCTURE; - - if (is_nil(lst)) { - error_res = LTI_NO_INTEGER; - error: - *rest = tail; - *integer = make_small(0); - return error_res; - } - if (is_not_list(lst)) - goto error; - - /* if first char is a '-' then it is a negative integer */ - if (CAR(list_val(lst)) == make_small('-')) { - neg = 1; - skip = 1; - lst = CDR(list_val(lst)); - if (is_not_list(lst)) { - tail = lst; - error_res = LTI_NO_INTEGER; - goto error; - } - } else if (CAR(list_val(lst)) == make_small('+')) { - /* ignore plus */ - skip = 1; - lst = CDR(list_val(lst)); - if (is_not_list(lst)) { - tail = lst; - error_res = LTI_NO_INTEGER; - goto error; - } - } - - /* Calculate size and do type check */ - - while(1) { - if (is_not_small(CAR(list_val(lst)))) { - break; - } - if (unsigned_val(CAR(list_val(lst))) < '0' || - unsigned_val(CAR(list_val(lst))) > '9') { - break; - } - ui = ui * 10; - ui = ui + unsigned_val(CAR(list_val(lst))) - '0'; - n++; - lst = CDR(list_val(lst)); - if (is_nil(lst)) { - break; - } - if (is_not_list(lst)) { - break; - } - } - - tail = lst; - if (!n) { - error_res = LTI_NO_INTEGER; - goto error; - } - - - /* If n <= 8 then we know it's a small int - ** since 2^27 = 134217728. If n > 8 then we must - ** construct a bignum and let that routine do the checking - */ - - if (n <= SMALL_DIGITS) { /* It must be small */ - if (neg) i = -(Sint)ui; - else i = (Sint)ui; - res = make_small(i); - } else { - /* Convert from log10 to log2 by multiplying with 1/log10(2)=3.3219 - which we round up to (3 + 1/3) */ - lg2 = (n+1)*3 + (n+1)/3 + 1; - m = (lg2+D_EXP-1)/D_EXP; /* number of digits */ - m = BIG_NEED_SIZE(m); /* number of words + thing */ - - hp = HAlloc(p, m); - hp_end = hp + m; - - lst = orig_list; - if (skip) - lst = CDR(list_val(lst)); - - /* load first digits (at least one digit) */ - if ((i = (n % D_DECIMAL_EXP)) == 0) - i = D_DECIMAL_EXP; - n -= i; - m = 0; - while(i--) { - m = 10*m + (unsigned_val(CAR(list_val(lst))) - '0'); - lst = CDR(list_val(lst)); - } - res = small_to_big(m, hp); /* load first digits */ - - while(n) { - i = D_DECIMAL_EXP; - n -= D_DECIMAL_EXP; - m = 0; - while(i--) { - m = 10*m + (unsigned_val(CAR(list_val(lst))) - '0'); - lst = CDR(list_val(lst)); - } - if (is_small(res)) - res = small_to_big(signed_val(res), hp); - res = big_times_small(res, D_DECIMAL_BASE, hp); - if (is_small(res)) - res = small_to_big(signed_val(res), hp); - res = big_plus_small(res, m, hp); - } - - if (neg) { - if (is_small(res)) - res = make_small(-signed_val(res)); - else { - Uint *big = big_val(res); /* point to thing */ - *big = bignum_header_neg(*big); - } - } - - if (is_not_small(res)) { - res = big_plus_small(res, 0, hp); /* includes conversion to small */ +/* + * Converts a list of ascii base10 digits to an integer fully or partially. + * Returns result and the remaining tail. + * On error returns: {error,not_a_list}, or {error, no_integer} + */ - if (is_not_small(res)) { - hp += (big_arity(res)+1); - } - } - HRelease(p,hp_end,hp); - } - *integer = res; - *rest = tail; - if (tail != NIL) { - return LTI_SOME_INTEGER; - } - return LTI_ALL_INTEGER; -} BIF_RETTYPE string_to_integer_1(BIF_ALIST_1) { Eterm res; Eterm tail; Eterm *hp; /* must be a list */ - switch (do_list_to_integer(BIF_P,BIF_ARG_1,&res,&tail)) { - /* HAlloc after do_list_to_integer as it - might HAlloc itself (bignum) */ + switch (erts_list_to_integer(BIF_P, BIF_ARG_1, 10, &res, &tail)) { + /* HAlloc after erts_list_to_integer as it might HAlloc itself (bignum) */ case LTI_BAD_STRUCTURE: hp = HAlloc(BIF_P,3); BIF_RET(TUPLE2(hp, am_error, am_not_a_list)); @@ -3100,13 +2945,14 @@ BIF_RETTYPE string_to_integer_1(BIF_ALIST_1) BIF_RETTYPE list_to_integer_1(BIF_ALIST_1) { - /* Using do_list_to_integer is about twice as fast as using + /* Using erts_list_to_integer is about twice as fast as using erts_chars_to_integer because we do not have to copy the entire list */ Eterm res; Eterm dummy; /* must be a list */ - if (do_list_to_integer(BIF_P,BIF_ARG_1,&res,&dummy) != LTI_ALL_INTEGER) { + if (erts_list_to_integer(BIF_P, BIF_ARG_1, 10, + &res, &dummy) != LTI_ALL_INTEGER) { BIF_ERROR(BIF_P,BADARG); } BIF_RET(res); @@ -3114,14 +2960,12 @@ BIF_RETTYPE list_to_integer_1(BIF_ALIST_1) BIF_RETTYPE list_to_integer_2(BIF_ALIST_2) { - /* Bif implementation is about 50% faster than pure erlang, and since we have erts_chars_to_integer now it is simpler as well. This could be optmized further if we did not have to copy the list to buf. */ int i; - Eterm res; - char *buf = NULL; + Eterm res, dummy; int base; i = erts_list_length(BIF_ARG_1); @@ -3129,31 +2973,16 @@ BIF_RETTYPE list_to_integer_2(BIF_ALIST_2) BIF_ERROR(BIF_P, BADARG); base = signed_val(BIF_ARG_2); - + if (base < 2 || base > 36) BIF_ERROR(BIF_P, BADARG); - /* Take fast path if base it 10 */ - if (base == 10) - return list_to_integer_1(BIF_P,&BIF_ARG_1); - - buf = (char *) erts_alloc(ERTS_ALC_T_TMP, i + 1); - - if (intlist_to_buf(BIF_ARG_1, buf, i) < 0) - goto list_to_integer_1_error; - buf[i] = '\0'; /* null terminal */ - - if ((res = erts_chars_to_integer(BIF_P,buf,i,base)) == THE_NON_VALUE) - goto list_to_integer_1_error; - - erts_free(ERTS_ALC_T_TMP, (void *) buf); + if (erts_list_to_integer(BIF_P, BIF_ARG_1, base, + &res, &dummy) != LTI_ALL_INTEGER) { + BIF_ERROR(BIF_P,BADARG); + } BIF_RET(res); - - list_to_integer_1_error: - erts_free(ERTS_ALC_T_TMP, (void *) buf); - BIF_ERROR(BIF_P, BADARG); - - } +} /**********************************************************************/ |