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-rw-r--r--ChangeLog6
-rw-r--r--bignum.c25
2 files changed, 26 insertions, 5 deletions
diff --git a/ChangeLog b/ChangeLog
index 33b8af84d58..ac6f45428da 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,9 @@
+Thu Jul 18 21:30:50 2013 Tanaka Akira <akr@fsij.org>
+
+ * bignum.c (bary_sq_fast): Specialize the last iteration of the
+ outer loop.
+ (bigfixize): A condition simplified.
+
Thu Jul 18 21:15:41 2013 Masaki Matsushita <glass.saga@gmail.com>
* array.c (rb_ary_equal): compare RARRAY_PTR() for performance
diff --git a/bignum.c b/bignum.c
index 22695a45a83..52086f51cdf 100644
--- a/bignum.c
+++ b/bignum.c
@@ -1605,7 +1605,11 @@ bary_sq_fast(BDIGIT *zds, size_t zn, BDIGIT *xds, size_t xn)
assert(xn * 2 <= zn);
BDIGITS_ZERO(zds, zn);
- for (i = 0; i < xn; i++) {
+
+ if (xn == 0)
+ return;
+
+ for (i = 0; i < xn-1; i++) {
v = (BDIGIT_DBL)xds[i];
if (!v)
continue;
@@ -1625,11 +1629,22 @@ bary_sq_fast(BDIGIT *zds, size_t zn, BDIGIT *xds, size_t xn)
c += (BDIGIT_DBL)zds[i + xn];
zds[i + xn] = BIGLO(c);
c = BIGDN(c);
- assert(c == 0 || i != xn-1);
- if (c && i != xn-1)
+ if (c)
zds[i + xn + 1] += (BDIGIT)c;
}
}
+
+ /* i == xn-1 */
+ v = (BDIGIT_DBL)xds[i];
+ if (!v)
+ return;
+ c = (BDIGIT_DBL)zds[i + i] + v * v;
+ zds[i + i] = BIGLO(c);
+ c = BIGDN(c);
+ if (c) {
+ c += (BDIGIT_DBL)zds[i + xn];
+ zds[i + xn] = BIGLO(c);
+ }
}
VALUE
@@ -2336,11 +2351,11 @@ bigfixize(VALUE x)
int i = (int)len;
u = 0;
while (i--) {
- u = (long)(BIGUP(u) + ds[i]);
+ u = (unsigned long)(BIGUP(u) + ds[i]);
}
}
#else /* SIZEOF_BDIGITS >= SIZEOF_LONG */
- if (1 < len || LONG_MAX < ds[0])
+ if (1 < len)
goto return_big;
else
u = ds[0];