bignum.c, numeric.c: add Integer#pow(b, m)

This commit is based on the pull-request #1320 created by Makoto Kishimoto.
[Feature #12508] [Feature #11003] [close GH-1320]

* bignum.c (rb_int_powm): Added for Integer#pow(b, m).

* internal.h (rb_int_powm): Declared to refer in numeric.c.

* bignum.c (bary_powm_gmp): Added for Integer#pow(b, m) using GMP.

* bignum.c (int_pow_tmp1): Added for implementing Integer#pow(b, m).

* bignum.c (int_pow_tmp2, int_pow_tmp3): ditto.

* internal.h (rb_num_positive_int_p): Moved from numeric.c for sharing
  the definition with bignum.c.

* internal.h (rb_num_negative_int_p, rb_num_compare_with_zero): ditto.

* numeric.c(negative_int_p): Moved to internal.h for sharing the
  definition with bignum.c.

* numeric.c (positive_int_p, compare_with_zero): ditto.

* numeric.c (rb_int_odd_p): Exported (renamed from int_odd_p).

* internal.h (rb_int_odd_p): ditto.

* internal.h (HALF_LONG_MSB): Added.

* numeric.c (SQRT_LONG_MAX): Redefined by using HALF_LONG_MSB.

* test/ruby/test_numeric.rb (test_pow): Added for Integer#pow(b, m).

git-svn-id: svn+ssh://ci.ruby-lang.org/ruby/trunk@61003 b2dd03c8-39d4-4d8f-98ff-823fe69b080e

1 files changed, 18 insertions, 60 deletions

diff --git a/numeric.c b/numeric.c
index 1858113c09..1639787154 100644
--- a/numeric.c
+++ b/numeric.c
@@ -162,7 +162,6 @@ static VALUE fix_mul(VALUE x, VALUE y);
 static VALUE fix_lshift(long, unsigned long);
 static VALUE fix_rshift(long, unsigned long);
 static VALUE int_pow(long x, unsigned long y);
-static VALUE int_odd_p(VALUE x);
 static VALUE int_even_p(VALUE x);
 static int int_round_zero_p(VALUE num, int ndigits);
 VALUE rb_int_floor(VALUE num, int ndigits);
@@ -271,17 +270,6 @@ rb_num_to_uint(VALUE val, unsigned int *ret)
 
 #define method_basic_p(klass) rb_method_basic_definition_p(klass, mid)
 
-static VALUE
-compare_with_zero(VALUE num, ID mid)
-{
-    VALUE zero = INT2FIX(0);
-    VALUE r = rb_check_funcall(num, mid, 1, &zero);
-    if (r == Qundef) {
-	rb_cmperr(num, zero);
-    }
-    return r;
-}
-
 static inline int
 int_pos_p(VALUE num)
 {
@@ -306,42 +294,10 @@ int_neg_p(VALUE num)
     rb_raise(rb_eTypeError, "not an Integer");
 }
 
-static inline int
-positive_int_p(VALUE num)
-{
-    const ID mid = '>';
-
-    if (FIXNUM_P(num)) {
-	if (method_basic_p(rb_cInteger))
-	    return FIXNUM_POSITIVE_P(num);
-    }
-    else if (RB_TYPE_P(num, T_BIGNUM)) {
-	if (method_basic_p(rb_cInteger))
-	    return BIGNUM_POSITIVE_P(num);
-    }
-    return RTEST(compare_with_zero(num, mid));
-}
-
-static inline int
-negative_int_p(VALUE num)
-{
-    const ID mid = '<';
-
-    if (FIXNUM_P(num)) {
-	if (method_basic_p(rb_cInteger))
-	    return FIXNUM_NEGATIVE_P(num);
-    }
-    else if (RB_TYPE_P(num, T_BIGNUM)) {
-	if (method_basic_p(rb_cInteger))
-	    return BIGNUM_NEGATIVE_P(num);
-    }
-    return RTEST(compare_with_zero(num, mid));
-}
-
 int
 rb_num_negative_p(VALUE num)
 {
-    return negative_int_p(num);
+    return rb_num_negative_int_p(num);
 }
 
 static VALUE
@@ -665,10 +621,10 @@ num_remainder(VALUE x, VALUE y)
     VALUE z = num_funcall1(x, '%', y);
 
     if ((!rb_equal(z, INT2FIX(0))) &&
-	((negative_int_p(x) &&
-	  positive_int_p(y)) ||
-	 (positive_int_p(x) &&
-	  negative_int_p(y)))) {
+	((rb_num_negative_int_p(x) &&
+	  rb_num_positive_int_p(y)) ||
+	 (rb_num_positive_int_p(x) &&
+	  rb_num_negative_int_p(y)))) {
 	return rb_funcall(z, '-', 1, y);
     }
     return z;
@@ -769,7 +725,7 @@ num_int_p(VALUE num)
 static VALUE
 num_abs(VALUE num)
 {
-    if (negative_int_p(num)) {
+    if (rb_num_negative_int_p(num)) {
 	return num_funcall0(num, idUMinus);
     }
     return num;
@@ -886,7 +842,7 @@ num_positive_p(VALUE num)
 	if (method_basic_p(rb_cInteger))
 	    return BIGNUM_POSITIVE_P(num) && !rb_bigzero_p(num) ? Qtrue : Qfalse;
     }
-    return compare_with_zero(num, mid);
+    return rb_num_compare_with_zero(num, mid);
 }
 
 /*
@@ -899,7 +855,7 @@ num_positive_p(VALUE num)
 static VALUE
 num_negative_p(VALUE num)
 {
-    return negative_int_p(num) ? Qtrue : Qfalse;
+    return rb_num_negative_int_p(num) ? Qtrue : Qfalse;
 }
 
 
@@ -2072,7 +2028,7 @@ int_round_half_down(SIGNED_VALUE x, SIGNED_VALUE y)
 static int
 int_half_p_half_even(VALUE num, VALUE n, VALUE f)
 {
-    return (int)int_odd_p(rb_int_idiv(n, f));
+    return (int)rb_int_odd_p(rb_int_idiv(n, f));
 }
 
 static int
@@ -2939,7 +2895,7 @@ rb_fix2uint(VALUE val)
     }
     num = FIX2ULONG(val);
 
-    check_uint(num, negative_int_p(val));
+    check_uint(num, rb_num_negative_int_p(val));
     return num;
 }
 #else
@@ -3025,7 +2981,7 @@ rb_fix2ushort(VALUE val)
     }
     num = FIX2ULONG(val);
 
-    check_ushort(num, negative_int_p(val));
+    check_ushort(num, rb_num_negative_int_p(val));
     return num;
 }
 
@@ -3168,8 +3124,8 @@ int_int_p(VALUE num)
  *  Returns +true+ if +int+ is an odd number.
  */
 
-static VALUE
-int_odd_p(VALUE num)
+VALUE
+rb_int_odd_p(VALUE num)
 {
     if (FIXNUM_P(num)) {
 	if (num & 2) {
@@ -3567,7 +3523,7 @@ rb_int_minus(VALUE x, VALUE y)
 }
 
 
-#define SQRT_LONG_MAX ((SIGNED_VALUE)1<<((SIZEOF_LONG*CHAR_BIT-1)/2))
+#define SQRT_LONG_MAX HALF_LONG_MSB
 /*tests if N*N would overflow*/
 #define FIT_SQRT_LONG(n) (((n)<SQRT_LONG_MAX)&&((n)>=-SQRT_LONG_MAX))
 
@@ -3976,7 +3932,7 @@ fix_pow(VALUE x, VALUE y)
 	    if (int_even_p(y)) return INT2FIX(1);
 	    else return INT2FIX(-1);
 	}
-	if (negative_int_p(y))
+	if (rb_num_negative_int_p(y))
 	    return num_funcall1(rb_rational_raw1(x), idPow, y);
 	if (a == 0) return INT2FIX(0);
 	x = rb_int2big(FIX2LONG(x));
@@ -5394,7 +5350,7 @@ Init_Numeric(void)
     rb_define_method(rb_cInteger, "to_s", int_to_s, -1);
     rb_define_alias(rb_cInteger, "inspect", "to_s");
     rb_define_method(rb_cInteger, "integer?", int_int_p, 0);
-    rb_define_method(rb_cInteger, "odd?", int_odd_p, 0);
+    rb_define_method(rb_cInteger, "odd?", rb_int_odd_p, 0);
     rb_define_method(rb_cInteger, "even?", int_even_p, 0);
     rb_define_method(rb_cInteger, "upto", int_upto, 1);
     rb_define_method(rb_cInteger, "downto", int_downto, 1);
@@ -5426,6 +5382,8 @@ Init_Numeric(void)
     rb_define_method(rb_cInteger, "fdiv", rb_int_fdiv, 1);
     rb_define_method(rb_cInteger, "**", rb_int_pow, 1);
 
+    rb_define_method(rb_cInteger, "pow", rb_int_powm, -1);
+
     rb_define_method(rb_cInteger, "abs", rb_int_abs, 0);
     rb_define_method(rb_cInteger, "magnitude", rb_int_abs, 0);