ruby-changes:52976
From: nobu <ko1@a...>
Date: Sat, 20 Oct 2018 11:49:26 +0900 (JST)
Subject: [ruby-changes:52976] nobu:r65190 (trunk): complex.c: small optimization of Complex#**
nobu 2018-10-20 11:49:18 +0900 (Sat, 20 Oct 2018) New Revision: 65190 https://svn.ruby-lang.org/cgi-bin/viewvc.cgi?view=revision&revision=65190 Log: complex.c: small optimization of Complex#** * complex.c (rb_complex_pow): calculate power of a Fixnum without allocating intermediate Complex objects, and avoid unexpected NaNs. Modified files: trunk/complex.c trunk/internal.h trunk/numeric.c trunk/rational.c trunk/test/ruby/test_complex.rb Index: internal.h =================================================================== --- internal.h (revision 65189) +++ internal.h (revision 65190) @@ -1174,6 +1174,7 @@ VALUE rb_complex_mul(VALUE, VALUE); https://github.com/ruby/ruby/blob/trunk/internal.h#L1174 VALUE rb_complex_abs(VALUE x); VALUE rb_complex_sqrt(VALUE x); VALUE rb_dbl_complex_polar(double abs, double ang); +VALUE rb_complex_pow(VALUE self, VALUE other); /* cont.c */ VALUE rb_obj_is_fiber(VALUE); @@ -1471,6 +1472,7 @@ VALUE rb_int_abs(VALUE num); https://github.com/ruby/ruby/blob/trunk/internal.h#L1472 VALUE rb_int_odd_p(VALUE num); int rb_int_positive_p(VALUE num); int rb_int_negative_p(VALUE num); +VALUE rb_num_pow(VALUE x, VALUE y); static inline VALUE rb_num_compare_with_zero(VALUE num, ID mid) @@ -1735,6 +1737,7 @@ VALUE rb_rational_reciprocal(VALUE x); https://github.com/ruby/ruby/blob/trunk/internal.h#L1737 VALUE rb_cstr_to_rat(const char *, int); VALUE rb_rational_abs(VALUE self); VALUE rb_rational_cmp(VALUE self, VALUE other); +VALUE rb_rational_pow(VALUE self, VALUE other); VALUE rb_numeric_quo(VALUE x, VALUE y); /* re.c */ Index: rational.c =================================================================== --- rational.c (revision 65189) +++ rational.c (revision 65190) @@ -1001,8 +1001,8 @@ f_odd_p(VALUE integer) https://github.com/ruby/ruby/blob/trunk/rational.c#L1001 * Rational(1, 2) ** 0 #=> (1/1) * Rational(1, 2) ** 0.0 #=> 1.0 */ -static VALUE -nurat_expt(VALUE self, VALUE other) +VALUE +rb_rational_pow(VALUE self, VALUE other) { if (k_numeric_p(other) && k_exact_zero_p(other)) return f_rational_new_bang1(CLASS_OF(self), ONE); @@ -1077,6 +1077,7 @@ nurat_expt(VALUE self, VALUE other) https://github.com/ruby/ruby/blob/trunk/rational.c#L1077 return rb_num_coerce_bin(self, other, rb_intern("**")); } } +#define nurat_expt rb_rational_pow /* * call-seq: Index: numeric.c =================================================================== --- numeric.c (revision 65189) +++ numeric.c (revision 65190) @@ -4077,6 +4077,22 @@ rb_int_pow(VALUE x, VALUE y) https://github.com/ruby/ruby/blob/trunk/numeric.c#L4077 return Qnil; } +VALUE +rb_num_pow(VALUE x, VALUE y) +{ + VALUE z = rb_int_pow(x, y); + if (!NIL_P(z)) return z; + if (RB_FLOAT_TYPE_P(x)) return rb_float_pow(x, y); + if (SPECIAL_CONST_P(x)) return Qnil; + switch (BUILTIN_TYPE(x)) { + case T_COMPLEX: + return rb_complex_pow(x, y); + case T_RATIONAL: + return rb_rational_pow(x, y); + } + return Qnil; +} + /* * Document-method: Integer#== * Document-method: Integer#=== Index: test/ruby/test_complex.rb =================================================================== --- test/ruby/test_complex.rb (revision 65189) +++ test/ruby/test_complex.rb (revision 65190) @@ -407,6 +407,10 @@ class Complex_Test < Test::Unit::TestCas https://github.com/ruby/ruby/blob/trunk/test/ruby/test_complex.rb#L407 r = c ** Rational(-2,3) assert_in_delta(0.432, r.real, 0.001) assert_in_delta(-0.393, r.imag, 0.001) + + c = Complex(0.0, -888888888888888.0)**8888 + assert_not_predicate(c.real, :nan?) + assert_not_predicate(c.imag, :nan?) end def test_cmp Index: complex.c =================================================================== --- complex.c (revision 65189) +++ complex.c (revision 65190) @@ -725,6 +725,19 @@ safe_mul(VALUE a, VALUE b, int az, int b https://github.com/ruby/ruby/blob/trunk/complex.c#L725 return f_mul(a, b); } +static void +comp_mul(VALUE areal, VALUE aimag, VALUE breal, VALUE bimag, VALUE *real, VALUE *imag) +{ + int arzero = f_zero_p(areal); + int aizero = f_zero_p(aimag); + int brzero = f_zero_p(breal); + int bizero = f_zero_p(bimag); + *real = f_sub(safe_mul(areal, breal, arzero, brzero), + safe_mul(aimag, bimag, aizero, bizero)); + *imag = f_add(safe_mul(areal, bimag, arzero, bizero), + safe_mul(aimag, breal, aizero, brzero)); +} + /* * call-seq: * cmp * numeric -> complex @@ -742,19 +755,9 @@ rb_complex_mul(VALUE self, VALUE other) https://github.com/ruby/ruby/blob/trunk/complex.c#L755 { if (RB_TYPE_P(other, T_COMPLEX)) { VALUE real, imag; - VALUE areal, aimag, breal, bimag; - int arzero, aizero, brzero, bizero; - get_dat2(self, other); - arzero = f_zero_p(areal = adat->real); - aizero = f_zero_p(aimag = adat->imag); - brzero = f_zero_p(breal = bdat->real); - bizero = f_zero_p(bimag = bdat->imag); - real = f_sub(safe_mul(areal, breal, arzero, brzero), - safe_mul(aimag, bimag, aizero, bizero)); - imag = f_add(safe_mul(areal, bimag, arzero, bizero), - safe_mul(aimag, breal, aizero, brzero)); + comp_mul(adat->real, adat->imag, bdat->real, bdat->imag, &real, &imag); return f_complex_new2(CLASS_OF(self), real, imag); } @@ -867,8 +870,8 @@ f_reciprocal(VALUE x) https://github.com/ruby/ruby/blob/trunk/complex.c#L870 * Complex('i') ** 2 #=> (-1+0i) * Complex(-8) ** Rational(1, 3) #=> (1.0000000000000002+1.7320508075688772i) */ -static VALUE -nucomp_expt(VALUE self, VALUE other) +VALUE +rb_complex_pow(VALUE self, VALUE other) { if (k_numeric_p(other) && k_exact_zero_p(other)) return f_complex_new_bang1(CLASS_OF(self), ONE); @@ -898,38 +901,45 @@ nucomp_expt(VALUE self, VALUE other) https://github.com/ruby/ruby/blob/trunk/complex.c#L901 return f_complex_polar(CLASS_OF(self), nr, ntheta); } if (FIXNUM_P(other)) { - if (f_gt_p(other, ZERO)) { - VALUE x, z; - long n; - - x = self; - z = x; - n = FIX2LONG(other) - 1; - - while (n) { - long q, r; - - while (1) { - get_dat1(x); - - q = n / 2; - r = n % 2; - - if (r) - break; - - x = nucomp_s_new_internal(CLASS_OF(self), - f_sub(f_mul(dat->real, dat->real), - f_mul(dat->imag, dat->imag)), - f_mul(f_mul(TWO, dat->real), dat->imag)); - n = q; - } - z = f_mul(z, x); - n--; - } - return z; + long n = FIX2LONG(other); + if (n == 0) { + return nucomp_s_new_internal(CLASS_OF(self), ONE, ZERO); + } + if (n < 0) { + self = f_reciprocal(self); + other = rb_int_uminus(other); + n = -n; + } + { + get_dat1(self); + VALUE xr = dat->real, xi = dat->imag, zr = xr, zi = xi; + + if (f_zero_p(xi)) { + zr = rb_num_pow(zr, other); + } + else if (f_zero_p(xr)) { + zi = rb_num_pow(zi, other); + if (n & 2) zi = f_negate(zi); + if (!(n & 1)) { + VALUE tmp = zr; + zr = zi; + zi = tmp; + } + } + else { + while (--n) { + long q, r; + + for (; q = n / 2, r = n % 2, r == 0; n = q) { + VALUE tmp = f_sub(f_mul(xr, xr), f_mul(xi, xi)); + xi = f_mul(f_mul(TWO, xr), xi); + xr = tmp; + } + comp_mul(zr, zi, xr, xi, &zr, &zi); + } + } + return nucomp_s_new_internal(CLASS_OF(self), zr, zi); } - return f_expt(f_reciprocal(self), rb_int_uminus(other)); } if (k_numeric_p(other) && f_real_p(other)) { VALUE r, theta; @@ -945,6 +955,7 @@ nucomp_expt(VALUE self, VALUE other) https://github.com/ruby/ruby/blob/trunk/complex.c#L955 } return rb_num_coerce_bin(self, other, id_expt); } +#define nucomp_expt rb_complex_pow /* * call-seq: -- ML: ruby-changes@q... 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