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, 54 insertions, 0 deletions

diff --git a/internal.h b/internal.h
index 9d33ed99d1..81ecb876ad 100644
--- a/internal.h
+++ b/internal.h
@@ -39,6 +39,12 @@ extern "C" {
 # endif
 #endif
 
+/* The most significant bit of the lower part of half-long integer.
+ * If sizeof(long) == 4, this is 0x8000.
+ * If sizeof(long) == 8, this is 0x80000000.
+ */
+#define HALF_LONG_MSB ((SIGNED_VALUE)1<<((SIZEOF_LONG*CHAR_BIT-1)/2))
+
 #define LIKELY(x) RB_LIKELY(x)
 #define UNLIKELY(x) RB_UNLIKELY(x)
 
@@ -1074,6 +1080,7 @@ VALUE rb_big_gt(VALUE x, VALUE y);
 VALUE rb_big_ge(VALUE x, VALUE y);
 VALUE rb_big_lt(VALUE x, VALUE y);
 VALUE rb_big_le(VALUE x, VALUE y);
+VALUE rb_int_powm(int const argc, VALUE * const argv, VALUE const num);
 
 /* class.c */
 VALUE rb_class_boot(VALUE);
@@ -1380,6 +1387,53 @@ VALUE rb_int_and(VALUE x, VALUE y);
 VALUE rb_int_lshift(VALUE x, VALUE y);
 VALUE rb_int_div(VALUE x, VALUE y);
 VALUE rb_int_abs(VALUE num);
+VALUE rb_int_odd_p(VALUE num);
+
+static inline VALUE
+rb_num_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
+rb_num_positive_int_p(VALUE num)
+{
+    const ID mid = '>';
+
+    if (FIXNUM_P(num)) {
+	if (rb_method_basic_definition_p(rb_cInteger, mid))
+	    return FIXNUM_POSITIVE_P(num);
+    }
+    else if (RB_TYPE_P(num, T_BIGNUM)) {
+	if (rb_method_basic_definition_p(rb_cInteger, mid))
+	    return BIGNUM_POSITIVE_P(num);
+    }
+    return RTEST(rb_num_compare_with_zero(num, mid));
+}
+
+
+static inline int
+rb_num_negative_int_p(VALUE num)
+{
+    const ID mid = '<';
+
+    if (FIXNUM_P(num)) {
+	if (rb_method_basic_definition_p(rb_cInteger, mid))
+	    return FIXNUM_NEGATIVE_P(num);
+    }
+    else if (RB_TYPE_P(num, T_BIGNUM)) {
+	if (rb_method_basic_definition_p(rb_cInteger, mid))
+	    return BIGNUM_NEGATIVE_P(num);
+    }
+    return RTEST(rb_num_compare_with_zero(num, mid));
+}
+
+
 VALUE rb_float_abs(VALUE flt);
 VALUE rb_float_equal(VALUE x, VALUE y);
 VALUE rb_float_eql(VALUE x, VALUE y);