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authorupstream source tree <ports@midipix.org>2015-03-15 20:14:05 -0400
committerupstream source tree <ports@midipix.org>2015-03-15 20:14:05 -0400
commit554fd8c5195424bdbcabf5de30fdc183aba391bd (patch)
tree976dc5ab7fddf506dadce60ae936f43f58787092 /gcc/testsuite/go.test/test/bench/pidigits.c
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diff --git a/gcc/testsuite/go.test/test/bench/pidigits.c b/gcc/testsuite/go.test/test/bench/pidigits.c
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+/*
+Redistribution and use in source and binary forms, with or without
+modification, are permitted provided that the following conditions are met:
+
+ * Redistributions of source code must retain the above copyright
+ notice, this list of conditions and the following disclaimer.
+
+ * 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.
+
+ * Neither the name of "The Computer Language Benchmarks Game" nor the
+ name of "The Computer Language Shootout Benchmarks" nor the names of
+ its contributors may be used to endorse or promote products derived
+ from this software without specific prior written permission.
+
+THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS 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 COPYRIGHT OWNER 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.
+*/
+
+/* The Computer Language Benchmarks Game
+ http://shootout.alioth.debian.org/
+
+ contributed by Paolo Bonzini & Sean Bartlett
+ modified by Michael Mellor
+*/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <gmp.h>
+
+static mpz_t numer, accum, denom, tmp1, tmp2;
+
+static int extract_digit()
+{
+ if (mpz_cmp(numer, accum) > 0)
+ return -1;
+
+ /* Compute (numer * 3 + accum) / denom */
+ mpz_mul_2exp(tmp1, numer, 1);
+ mpz_add(tmp1, tmp1, numer);
+ mpz_add(tmp1, tmp1, accum);
+ mpz_fdiv_qr(tmp1, tmp2, tmp1, denom);
+
+ /* Now, if (numer * 4 + accum) % denom... */
+ mpz_add(tmp2, tmp2, numer);
+
+ /* ... is normalized, then the two divisions have the same result. */
+ if (mpz_cmp(tmp2, denom) >= 0)
+ return -1;
+
+ return mpz_get_ui(tmp1);
+}
+
+static void next_term(unsigned int k)
+{
+ unsigned int y2 = k*2 + 1;
+
+ mpz_mul_2exp(tmp1, numer, 1);
+ mpz_add(accum, accum, tmp1);
+ mpz_mul_ui(accum, accum, y2);
+ mpz_mul_ui(numer, numer, k);
+ mpz_mul_ui(denom, denom, y2);
+}
+
+static void eliminate_digit(unsigned int d)
+{
+ mpz_submul_ui(accum, denom, d);
+ mpz_mul_ui(accum, accum, 10);
+ mpz_mul_ui(numer, numer, 10);
+}
+
+static void pidigits(unsigned int n)
+{
+ int d;
+ unsigned int i = 0, k = 0, m;
+ mpz_init(tmp1);
+ mpz_init(tmp2);
+ mpz_init_set_ui(numer, 1);
+ mpz_init_set_ui(accum, 0);
+ mpz_init_set_ui(denom, 1);
+
+ for(;;)
+ {
+ do {
+ k++;
+ next_term(k);
+ d = extract_digit();
+ } while(d == -1);
+
+ putchar(d + '0');
+
+ i++;
+ m = i%10;
+ if(m == 0)
+ printf("\t:%d\n", i);
+ if(i >= n)
+ break;
+ eliminate_digit(d);
+ }
+
+ if(m) {
+ m = 10 - m;
+ while(m--)
+ putchar(' ');
+ printf("\t:%d\n", n);
+ }
+}
+
+int main(int argc, char **argv)
+{
+ pidigits(argc > 1 ? atoi(argv[1]) : 27);
+ return 0;
+}