New function mpn_gcd_22.

* mpn/generic/gcd.c (gcd_2): Moved to gcd_22.c below.
(mpn_gcd): Adapt for calling gcd_22.
* mpn/generic/gcd_22.c (mpn_gcd_22): New file and function.
* gmp-impl.h (mp_double_limb_t): New (typedef) struct.
* configure.ac (gmp_mpn_functions): Added gcd_22.

* tests/mpn/t-gcd_22.c: New test.
* tests/mpn/Makefile.am (check_PROGRAMS): Add t-gcd_22.
* tests/refmpz.c (refmpz_gcd): New function (plain binary gcd).

2 files changed, 84 insertions, 1 deletions

diff --git a/tests/mpn/Makefile.am b/tests/mpn/Makefile.am
index 9f1cd8868..2fae43900 100644
--- a/tests/mpn/Makefile.am
+++ b/tests/mpn/Makefile.am
@@ -29,7 +29,7 @@ check_PROGRAMS = t-asmtype t-aors_1 t-divrem_1 t-mod_1 t-fat t-get_d	\
   t-toom2-sqr t-toom3-sqr t-toom4-sqr t-toom6-sqr t-toom8-sqr		\
   t-div t-mul t-mullo t-sqrlo t-mulmod_bnm1 t-sqrmod_bnm1 t-mulmid	\
   t-hgcd t-hgcd_appr t-matrix22 t-invert t-bdiv t-fib2m			\
-  t-broot t-brootinv t-minvert t-sizeinbase t-gcd_11
+  t-broot t-brootinv t-minvert t-sizeinbase t-gcd_11 t-gcd_22
 
 EXTRA_DIST = toom-shared.h toom-sqr-shared.h
 
diff --git a/tests/mpn/t-gcd_22.c b/tests/mpn/t-gcd_22.c
new file mode 100644
index 000000000..4761680c9
--- /dev/null
+++ b/tests/mpn/t-gcd_22.c
@@ -0,0 +1,83 @@
+/* Test mpn_gcd_22.
+
+Copyright 2019 Free Software Foundation, Inc.
+
+This file is part of the GNU MP Library test suite.
+
+The GNU MP Library test suite is free software; you can redistribute it
+and/or modify it under the terms of the GNU General Public License as
+published by the Free Software Foundation; either version 3 of the License,
+or (at your option) any later version.
+
+The GNU MP Library test suite is distributed in the hope that it will be
+useful, but WITHOUT ANY WARRANTY; without even the implied warranty of
+MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General
+Public License for more details.
+
+You should have received a copy of the GNU General Public License along with
+the GNU MP Library test suite.  If not, see https://www.gnu.org/licenses/.  */
+
+#include <stdio.h>
+#include <stdlib.h>
+
+#include "gmp-impl.h"
+#include "tests.h"
+
+#ifndef COUNT
+#define COUNT 10000
+#endif
+
+static void
+one_test (mpz_srcptr a, mpz_srcptr b, mpz_srcptr ref)
+{
+  mp_double_limb_t r = mpn_gcd_22 (mpz_getlimbn (a, 1), mpz_getlimbn (a, 0),
+				   mpz_getlimbn (b, 1), mpz_getlimbn (b, 0));
+  if (r.d0 != mpz_getlimbn (ref, 0) || r.d1 != mpz_getlimbn (ref, 1))
+    {
+      gmp_fprintf (stderr,
+		   "gcd_22 (0x%Zx, 0x%Zx) failed, got: g1 = 0x%Mx g0 = %Mx, ref: 0x%Zx\n",
+                   a, b, r.d1, r.d0, ref);
+      abort();
+    }
+}
+
+int
+main (int argc, char **argv)
+{
+  mpz_t a, b, ref;
+  int count = COUNT;
+  int test;
+  gmp_randstate_ptr rands;
+
+  TESTS_REPS (count, argv, argc);
+
+  tests_start ();
+  rands = RANDS;
+
+  mpz_init (a);
+  mpz_init (b);
+  mpz_init (ref);
+  for (test = 0; test < count; test++)
+    {
+      mp_bitcnt_t size = 1 + gmp_urandomm_ui(rands, 2*GMP_NUMB_BITS);
+      if (test & 1)
+	{
+	  mpz_urandomb (a, rands, size);
+	  mpz_urandomb (b, rands, size);
+	}
+      else
+	{
+	  mpz_rrandomb (a, rands, size);
+	  mpz_rrandomb (b, rands, size);
+	}
+
+      mpz_setbit (a, 0);
+      mpz_setbit (b, 0);
+      refmpz_gcd (ref, a, b);
+      one_test (a, b, ref);
+    }
+
+  mpz_clear (a);
+  mpz_clear (b);
+  mpz_clear (ref);
+}