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-rw-r--r--Makefile7
-rw-r--r--pi_bbp.c340
2 files changed, 175 insertions, 172 deletions
diff --git a/Makefile b/Makefile
index 5c2f6c5..c12e440 100644
--- a/Makefile
+++ b/Makefile
@@ -1,11 +1,12 @@
BINS = ascii class depipe_strings dup fpipe pipe realloc strpbrk strsep \
- tokenizer getopt prime_mask
+ tokenizer getopt prime_mask linked_list pi_bbp
CC = gcc
+CFLAGS = -Wall -std=gnu99 -pedantic
DBGFLAGS = -g -O0
ifdef DEBUG
- CFLAGS = $(DBGFLAGS) -D DEBUG -std=gnu99 -Wall -pedantic
+ CFLAGS += $(DBGFLAGS) -D DEBUG
else
- CFLAGS = -O2 -std=gnu99 -Wall -pedantic
+ CFLAGS += -O2 -mtune=native -march=native
endif
LDFLAGS = -lm
diff --git a/pi_bbp.c b/pi_bbp.c
index c51944f..40c1ca7 100644
--- a/pi_bbp.c
+++ b/pi_bbp.c
@@ -1,169 +1,171 @@
-/*
- * http://www.cut-the-knot.org/Curriculum/Algorithms/SpigotForPi.shtml
- *
- * Original code is available in public domain
- * Pi Decimal Point Calculation using BBP (named after Bailey-Borwein-Plouffe)
- *
- */
-
-#include <stdio.h>
-#include <string.h>
-#include <stdlib.h>
-#include <wchar.h>
-#include <time.h>
-#include <sys/time.h>
-
-/* globals */
-int printed = 0;
-int line = 1;
-int mulof2 = 1;
-
-/* function prototypes */
-inline void out_dig(long unsigned, struct timeval *);
-inline void printTime(struct timeval *);
-int do_calc(char **);
-
-inline void out_dig(long unsigned dig, struct timeval *before)
-{
- putchar(dig);
- printed++;
-
- if ((printed % 50) == 0)
- {
- if ((line % (20 * mulof2)) == 0)
- {
- printf("\n%dK: ", mulof2);
- mulof2 *= 2;
-
- printTime(before);
- }
-
- printf("\nd %06d: ", 50 * line);
- line++;
- }
- else if ((printed % 10) == 0)
- putchar(' ');
-}
-
-inline void printTime(struct timeval *before)
-{
- struct timeval after;
- gettimeofday(&after, 0);
- long unsigned int elapsed_ms = (after.tv_sec - before->tv_sec) * 1000 +
- (after.tv_usec - before->tv_usec) / 1000;
- unsigned int seconds_n = elapsed_ms / 1000;
- unsigned int milliseconds_n = elapsed_ms % 1000;
-
- printf("time elapsed: %lu.%lu seconds\n", seconds_n, milliseconds_n);
-}
-
-int do_calc(char **argv)
-{
- long unsigned int i, j, k, nines, predigit;
- long unsigned int q, x, digits_n, len;
- long unsigned int *pi;
- long unsigned int alloc;
-
- digits_n = atol(argv[1]);
- if (digits_n < 1)
- return 0;
-
- len = (digits_n * 10) / 3;
- alloc = sizeof(long unsigned int) * (len+1);
-
- pi = (long unsigned int *) malloc(alloc);
- if (!pi)
- {
- perror("malloc");
- exit(-1);
- }
- else
- printf("\n\tPi Decimal Digit Calculation\n"
- "allocated %ldKb of heap memory\n", alloc / 1024);
-
- for (i = 0; i < len; i++)
- pi[i] = 2;
-
- /* wchar_t pi_c = 0x03c0; */
- printf("Pi value: 3.");
-
- nines = 0;
- predigit = 0;
-
- struct timeval before;
- gettimeofday(&before, 0);
-
- for (j = 0; j <= digits_n; j++)
- {
- q = 0;
-
- for (i = len; i > 0; i--)
- {
- x = 10 * pi[i] + q * i;
- pi[i] = x % (2 * i - 1);
- q = x / (2 * i - 1);
- }
-
- pi[1] = q % 10;
- q = q / 10;
-
- if (q == 9)
- nines++;
- else if (q == 10)
- {
- out_dig('1' + predigit, &before);
-
- while (nines)
- {
- out_dig('0', &before);
- nines--;
- }
-
- predigit = 0;
- fflush(stdout);
- }
- else
- {
- if (j > 1)
- out_dig('0' + predigit, &before);
-
- while (nines)
- {
- out_dig('9', &before);
- nines--;
- }
-
- predigit = q;
- fflush(stdout);
- }
- }
-
- out_dig(predigit + '0', &before);
- puts("");
- free(pi);
-
- struct timeval after;
- gettimeofday(&after, 0);
- long unsigned int elapsed_ms = (after.tv_sec - before.tv_sec) * 1000 +
- (after.tv_usec - before.tv_usec) / 1000;
- unsigned int seconds_n = elapsed_ms / 1000;
- unsigned int milliseconds_n = elapsed_ms % 1000;
-
- printf("\nPi calculation to %d'th decimal point finished\n"
- "\tTotal Time: %lu.%lu seconds\n", digits_n, seconds_n, milliseconds_n);
-}
-
-int main(int argc, char *argv[])
-{
- if (argc < 2)
- {
- fprintf(stderr, "%s <number of decimal digits to compute>\n", argv[0]);
- return 1;
- }
-
- if (!do_calc(argv))
- printf("do_calc() failed to execute\n");
-
- return 0;
-}
-
+/*
+ * http://www.cut-the-knot.org/Curriculum/Algorithms/SpigotForPi.shtml
+ *
+ * Original code is available in public domain
+ * Pi Decimal Point Calculation using BBP (named after Bailey-Borwein-Plouffe)
+ *
+ */
+
+#include <stdio.h>
+#include <string.h>
+#include <stdlib.h>
+#include <wchar.h>
+#include <time.h>
+#include <sys/time.h>
+
+/* globals */
+int printed = 0;
+int line = 1;
+int mulof2 = 1;
+
+/* function prototypes */
+inline void out_dig(long unsigned, struct timeval *);
+inline void printTime(struct timeval *);
+int do_calc(char **);
+
+inline void out_dig(long unsigned dig, struct timeval *before)
+{
+ putchar(dig);
+ printed++;
+
+ if ((printed % 50) == 0)
+ {
+ if ((line % (20 * mulof2)) == 0)
+ {
+ printf("\n%dK: ", mulof2);
+ mulof2 *= 2;
+
+ printTime(before);
+ }
+
+ printf("\nd %06d: ", 50 * line);
+ line++;
+ }
+ else if ((printed % 10) == 0)
+ putchar(' ');
+}
+
+inline void printTime(struct timeval *before)
+{
+ struct timeval after;
+ gettimeofday(&after, 0);
+ long unsigned int elapsed_ms = (after.tv_sec - before->tv_sec) * 1000 +
+ (after.tv_usec - before->tv_usec) / 1000;
+ unsigned int seconds_n = elapsed_ms / 1000;
+ unsigned int milliseconds_n = elapsed_ms % 1000;
+
+ printf("time elapsed: %u.%u seconds\n", seconds_n, milliseconds_n);
+}
+
+int do_calc(char **argv)
+{
+ long unsigned int i, j, nines, predigit;
+ long unsigned int q, x, digits_n, len;
+ long unsigned int *pi;
+ long unsigned int alloc;
+
+ digits_n = atol(argv[1]);
+ if (digits_n < 1)
+ return -1;
+
+ len = (digits_n * 10) / 3;
+ alloc = sizeof(long unsigned int) * (len+1);
+
+ pi = (long unsigned int *) malloc(alloc);
+ if (!pi)
+ {
+ perror("malloc");
+ exit(-1);
+ }
+ else
+ printf("\n\tPi Decimal Digit Calculation\n"
+ "allocated %ldKb of heap memory\n", alloc / 1024);
+
+ for (i = 0; i < len; i++)
+ pi[i] = 2;
+
+ /* wchar_t pi_c = 0x03c0; */
+ printf("Pi value: 3.");
+
+ nines = 0;
+ predigit = 0;
+
+ struct timeval before;
+ gettimeofday(&before, 0);
+
+ for (j = 0; j <= digits_n; j++)
+ {
+ q = 0;
+
+ for (i = len; i > 0; i--)
+ {
+ x = 10 * pi[i] + q * i;
+ pi[i] = x % (2 * i - 1);
+ q = x / (2 * i - 1);
+ }
+
+ pi[1] = q % 10;
+ q = q / 10;
+
+ if (q == 9)
+ nines++;
+ else if (q == 10)
+ {
+ out_dig('1' + predigit, &before);
+
+ while (nines)
+ {
+ out_dig('0', &before);
+ nines--;
+ }
+
+ predigit = 0;
+ fflush(stdout);
+ }
+ else
+ {
+ if (j > 1)
+ out_dig('0' + predigit, &before);
+
+ while (nines)
+ {
+ out_dig('9', &before);
+ nines--;
+ }
+
+ predigit = q;
+ fflush(stdout);
+ }
+ }
+
+ out_dig(predigit + '0', &before);
+ puts("");
+ free(pi);
+
+ struct timeval after;
+ gettimeofday(&after, 0);
+ long unsigned int elapsed_ms = (after.tv_sec - before.tv_sec) * 1000 +
+ (after.tv_usec - before.tv_usec) / 1000;
+ unsigned int seconds_n = elapsed_ms / 1000;
+ unsigned int milliseconds_n = elapsed_ms % 1000;
+
+ printf("\nPi calculation to %lu'th decimal point finished\n"
+ "\tTotal Time: %u.%u seconds\n", digits_n, seconds_n, milliseconds_n);
+
+ return 1;
+}
+
+int main(int argc, char *argv[])
+{
+ if (argc < 2)
+ {
+ fprintf(stderr, "%s <number of decimal digits to compute>\n", argv[0]);
+ return 1;
+ }
+
+ if (!do_calc(argv))
+ printf("do_calc() failed to execute\n");
+
+ return 0;
+}
+
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