mrcImageOpticalFlow & mrcImageLucasKanade & mrcImageHornSchunckの変更

[eos/base.git] / util / src / TclTk / tcl8.6.12 / libtommath / bn_s_mp_mul_high_digs.c

diff --git a/util/src/TclTk/tcl8.6.12/libtommath/bn_s_mp_mul_high_digs.c b/util/src/TclTk/tcl8.6.12/libtommath/bn_s_mp_mul_high_digs.c
new file mode 100644 (file)
index 0000000..2bb2a50
--- /dev/null
+++ b/util/src/TclTk/tcl8.6.12/libtommath/bn_s_mp_mul_high_digs.c
@@ -0,0 +1,64 @@
+#include "tommath_private.h"
+#ifdef BN_S_MP_MUL_HIGH_DIGS_C
+/* LibTomMath, multiple-precision integer library -- Tom St Denis */
+/* SPDX-License-Identifier: Unlicense */
+
+/* multiplies |a| * |b| and does not compute the lower digs digits
+ * [meant to get the higher part of the product]
+ */
+mp_err s_mp_mul_high_digs(const mp_int *a, const mp_int *b, mp_int *c, int digs)
+{
+   mp_int   t;
+   int      pa, pb, ix, iy;
+   mp_err   err;
+   mp_digit u;
+   mp_word  r;
+   mp_digit tmpx, *tmpt, *tmpy;
+
+   /* can we use the fast multiplier? */
+   if (MP_HAS(S_MP_MUL_HIGH_DIGS_FAST)
+       && ((a->used + b->used + 1) < MP_WARRAY)
+       && (MP_MIN(a->used, b->used) < MP_MAXFAST)) {
+      return s_mp_mul_high_digs_fast(a, b, c, digs);
+   }
+
+   if ((err = mp_init_size(&t, a->used + b->used + 1)) != MP_OKAY) {
+      return err;
+   }
+   t.used = a->used + b->used + 1;
+
+   pa = a->used;
+   pb = b->used;
+   for (ix = 0; ix < pa; ix++) {
+      /* clear the carry */
+      u = 0;
+
+      /* left hand side of A[ix] * B[iy] */
+      tmpx = a->dp[ix];
+
+      /* alias to the address of where the digits will be stored */
+      tmpt = &(t.dp[digs]);
+
+      /* alias for where to read the right hand side from */
+      tmpy = b->dp + (digs - ix);
+
+      for (iy = digs - ix; iy < pb; iy++) {
+         /* calculate the double precision result */
+         r       = (mp_word)*tmpt +
+                   ((mp_word)tmpx * (mp_word)*tmpy++) +
+                   (mp_word)u;
+
+         /* get the lower part */
+         *tmpt++ = (mp_digit)(r & (mp_word)MP_MASK);
+
+         /* carry the carry */
+         u       = (mp_digit)(r >> (mp_word)MP_DIGIT_BIT);
+      }
+      *tmpt = u;
+   }
+   mp_clamp(&t);
+   mp_exch(&t, c);
+   mp_clear(&t);
+   return MP_OKAY;
+}
+#endif