diff options
| -rw-r--r-- | ChangeLog | 6 | ||||
| -rw-r--r-- | bignum.c | 51 |
2 files changed, 42 insertions, 15 deletions
@@ -1,3 +1,9 @@ +Tue Jul 2 20:25:04 2013 Tanaka Akira <akr@fsij.org> + + * bignum.c (rb_cstr_to_inum): Use BDIGIT_DBL to collect adjacent digits. + (BDIGIT_DBL_MAX): New macro. + (maxpow_in_bdigit_dbl): New function. + Tue Jul 2 17:23:33 2013 Shugo Maeda <shugo@ruby-lang.org> * doc/syntax/refinements.rdoc: add description of Module#using and @@ -61,6 +61,7 @@ static VALUE big_three = Qnil; #define BIGDN(x) RSHIFT((x),BITSPERDIG) #define BIGLO(x) ((BDIGIT)((x) & BDIGMAX)) #define BDIGMAX ((BDIGIT)(BIGRAD-1)) +#define BDIGIT_DBL_MAX (~(BDIGIT_DBL)0) #if SIZEOF_BDIGITS == 2 # define swap_bdigit(x) swap16(x) @@ -220,6 +221,23 @@ static int nlz(BDIGIT x) { return nlz128((uint128_t)x); } 32 - nlz32(x)) #endif +static BDIGIT_DBL +maxpow_in_bdigit_dbl(int base, int *exp_ret) +{ + BDIGIT_DBL maxpow; + int exponent; + + maxpow = base; + exponent = 1; + while (maxpow <= BDIGIT_DBL_MAX / base) { + maxpow *= base; + exponent++; + } + + *exp_ret = exponent; + return maxpow; +} + static int bary_zero_p(BDIGIT *xds, size_t nx) { @@ -2071,31 +2089,33 @@ rb_cstr_to_inum(const char *str, int base, int badcheck) } } else { - BDIGIT hbase; - VALUE hbasev; - int hbase_numdigits; + int digits_per_bdigits_dbl; + BDIGIT_DBL power; + VALUE powerv; int j; size_t num_bdigits; size_t unit; VALUE tmpu = 0, tmpv = 0; BDIGIT *uds, *vds, *tds; - calc_hbase(base, &hbase, &hbase_numdigits); + + power = maxpow_in_bdigit_dbl(base, &digits_per_bdigits_dbl); size = p - buf; - num_bdigits = roomof(size, hbase_numdigits); + num_bdigits = roomof(size, digits_per_bdigits_dbl)*2; uds = ALLOCV_N(BDIGIT, tmpu, num_bdigits); vds = ALLOCV_N(BDIGIT, tmpv, num_bdigits); - hbasev = bignew(1, 1); - BDIGITS(hbasev)[0] = hbase; + powerv = bignew(2, 1); + BDIGITS(powerv)[0] = BIGLO(power); + BDIGITS(powerv)[1] = BIGDN(power); i = 0; while (buf < p) { int m; - BDIGIT d = 0; - if (hbase_numdigits <= p - buf) { - m = hbase_numdigits; + BDIGIT_DBL d = 0; + if (digits_per_bdigits_dbl <= p - buf) { + m = digits_per_bdigits_dbl; } else { m = (int)(p - buf); @@ -2104,23 +2124,24 @@ rb_cstr_to_inum(const char *str, int base, int badcheck) for (j = 0; j < m; j++) { d = d * base + p[j]; } - uds[i++] = d; + uds[i++] = BIGLO(d); + uds[i++] = BIGDN(d); } - for (unit = 1; unit < num_bdigits; unit *= 2) { + for (unit = 2; unit < num_bdigits; unit *= 2) { for (i = 0; i < num_bdigits; i += unit*2) { if (2*unit <= num_bdigits - i) { - bary_mul2(vds+i, unit*2, BDIGITS(hbasev), RBIGNUM_LEN(hbasev), uds+i+unit, unit); + bary_mul2(vds+i, unit*2, BDIGITS(powerv), RBIGNUM_LEN(powerv), uds+i+unit, unit); bary_add(vds+i, unit*2, vds+i, unit*2, uds+i, unit); } else if (unit <= num_bdigits - i) { - bary_mul2(vds+i, num_bdigits-i, BDIGITS(hbasev), RBIGNUM_LEN(hbasev), uds+i+unit, num_bdigits-(i+unit)); + bary_mul2(vds+i, num_bdigits-i, BDIGITS(powerv), RBIGNUM_LEN(powerv), uds+i+unit, num_bdigits-(i+unit)); bary_add(vds+i, num_bdigits-i, vds+i, num_bdigits-i, uds+i, unit); } else { MEMCPY(vds+i, uds+i, BDIGIT, num_bdigits-i); } } - hbasev = bigtrunc(bigmul0(hbasev, hbasev)); + powerv = bigtrunc(bigmul0(powerv, powerv)); tds = vds; vds = uds; uds = tds; |