Issue #7652: Integrate the decimal floating point libmpdec library to speed

up the decimal module. Performance gains of the new C implementation are
between 12x and 80x, depending on the application.

1 files changed, 81 insertions, 0 deletions

diff --git a/Modules/_decimal/libmpdec/fnt.c b/Modules/_decimal/libmpdec/fnt.c
new file mode 100644
index 0000000..9311653
--- /dev/null
+++ b/Modules/_decimal/libmpdec/fnt.c
@@ -0,0 +1,81 @@
+/*
+ * Copyright (c) 2008-2012 Stefan Krah. All rights reserved.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ *
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS "AS IS" AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+
+#include "mpdecimal.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <assert.h>
+#include "bits.h"
+#include "difradix2.h"
+#include "numbertheory.h"
+#include "fnt.h"
+
+
+/* Bignum: Fast transform for medium-sized coefficients. */
+
+
+/* forward transform, sign = -1 */
+int
+std_fnt(mpd_uint_t *a, mpd_size_t n, int modnum)
+{
+    struct fnt_params *tparams;
+
+    assert(ispower2(n));
+    assert(n >= 4);
+    assert(n <= 3*MPD_MAXTRANSFORM_2N);
+
+    if ((tparams = _mpd_init_fnt_params(n, -1, modnum)) == NULL) {
+        return 0;
+    }
+    fnt_dif2(a, n, tparams);
+
+    mpd_free(tparams);
+    return 1;
+}
+
+/* reverse transform, sign = 1 */
+int
+std_inv_fnt(mpd_uint_t *a, mpd_size_t n, int modnum)
+{
+    struct fnt_params *tparams;
+
+    assert(ispower2(n));
+    assert(n >= 4);
+    assert(n <= 3*MPD_MAXTRANSFORM_2N);
+
+    if ((tparams = _mpd_init_fnt_params(n, 1, modnum)) == NULL) {
+        return 0;
+    }
+    fnt_dif2(a, n, tparams);
+
+    mpd_free(tparams);
+    return 1;
+}
+
+
+