--- /dev/null
+/* mpn_toom44_mul -- Multiply {ap,an} and {bp,bn} where an and bn are close in
+ size. Or more accurately, bn <= an < (4/3)bn.
+
+ Contributed to the GNU project by Torbjorn Granlund and Marco Bodrato.
+
+ THE FUNCTION IN THIS FILE IS INTERNAL WITH A MUTABLE INTERFACE. IT IS ONLY
+ SAFE TO REACH IT THROUGH DOCUMENTED INTERFACES. IN FACT, IT IS ALMOST
+ GUARANTEED THAT IT WILL CHANGE OR DISAPPEAR IN A FUTURE GNU MP RELEASE.
+
+Copyright 2006, 2007, 2008 Free Software Foundation, Inc.
+
+This file is part of the GNU MP Library.
+
+The GNU MP Library is free software; you can redistribute it and/or modify
+it under the terms of the GNU Lesser General Public License as published by
+the Free Software Foundation; either version 3 of the License, or (at your
+option) any later version.
+
+The GNU MP Library is distributed in the hope that it will be useful, but
+WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
+or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
+License for more details.
+
+You should have received a copy of the GNU Lesser General Public License
+along with the GNU MP Library. If not, see http://www.gnu.org/licenses/. */
+
+
+/*
+ Things to work on:
+
+ 1. Trim allocation. The allocations for as1, asm1, bs1, and bsm1 could be
+ avoided by instead reusing the pp area and the scratch area.
+ 2. Use new toom functions for the recursive calls.
+*/
+
+#include "gmp.h"
+#include "gmp-impl.h"
+
+/* Evaluate in: -1, -1/2, 0, +1/2, +1, +2, +inf
+
+ <-s--><--n--><--n--><--n-->
+ ____ ______ ______ ______
+ |_a3_|___a2_|___a1_|___a0_|
+ |b3_|___b2_|___b1_|___b0_|
+ <-t-><--n--><--n--><--n-->
+
+ v0 = a0 * b0 # A(0)*B(0)
+ v1 = ( a0+ a1+ a2+ a3)*( b0+ b1+ b2+ b3) # A(1)*B(1) ah <= 3 bh <= 3
+ vm1 = ( a0- a1+ a2- a3)*( b0- b1+ b2- b3) # A(-1)*B(-1) |ah| <= 1 |bh| <= 1
+ v2 = ( a0+2a1+4a2+8a3)*( b0+2b1+4b2+8b3) # A(2)*B(2) ah <= 14 bh <= 14
+ vh = (8a0+4a1+2a2+ a3)*(8b0+4b1+2b2+ b3) # A(1/2)*B(1/2) ah <= 14 bh <= 14
+ vmh = (8a0-4a1+2a2- a3)*(8b0-4b1+2b2- b3) # A(-1/2)*B(-1/2) -4<=ah<=9 -4<=bh<=9
+ vinf= a3 * b2 # A(inf)*B(inf)
+*/
+
+#if TUNE_PROGRAM_BUILD
+#define MAYBE_mul_basecase 1
+#define MAYBE_mul_toom22 1
+#define MAYBE_mul_toom44 1
+#else
+#define MAYBE_mul_basecase \
+ (MUL_TOOM44_THRESHOLD < 4 * MUL_KARATSUBA_THRESHOLD)
+#define MAYBE_mul_toom22 \
+ (MUL_TOOM44_THRESHOLD < 4 * MUL_TOOM33_THRESHOLD)
+#define MAYBE_mul_toom44 \
+ (MUL_FFT_THRESHOLD >= 4 * MUL_TOOM44_THRESHOLD)
+#endif
+
+#define TOOM44_MUL_N_REC(p, a, b, n, ws) \
+ do { \
+ if (MAYBE_mul_basecase \
+ && BELOW_THRESHOLD (n, MUL_KARATSUBA_THRESHOLD)) \
+ mpn_mul_basecase (p, a, n, b, n); \
+ else if (MAYBE_mul_toom22 \
+ && BELOW_THRESHOLD (n, MUL_TOOM33_THRESHOLD)) \
+ mpn_kara_mul_n (p, a, b, n, ws); \
+ else if (! MAYBE_mul_toom44 \
+ || BELOW_THRESHOLD (n, MUL_TOOM44_THRESHOLD)) \
+ mpn_toom3_mul_n (p, a, b, n, ws); \
+ else \
+ mpn_toom44_mul (p, a, n, b, n, ws); \
+ } while (0)
+
+void
+mpn_toom44_mul (mp_ptr pp,
+ mp_srcptr ap, mp_size_t an,
+ mp_srcptr bp, mp_size_t bn,
+ mp_ptr scratch)
+{
+ mp_size_t n, s, t;
+ mp_limb_t cy;
+ mp_ptr gp, hp;
+ mp_ptr as1, asm1, as2, ash, asmh;
+ mp_ptr bs1, bsm1, bs2, bsh, bsmh;
+ enum toom4_flags flags;
+ TMP_DECL;
+
+#define a0 ap
+#define a1 (ap + n)
+#define a2 (ap + 2*n)
+#define a3 (ap + 3*n)
+#define b0 bp
+#define b1 (bp + n)
+#define b2 (bp + 2*n)
+#define b3 (bp + 3*n)
+
+ n = (an + 3) >> 2;
+
+ s = an - 3 * n;
+ t = bn - 3 * n;
+
+ ASSERT (an >= bn);
+
+ ASSERT (0 < s && s <= n);
+ ASSERT (0 < t && t <= n);
+
+ TMP_MARK;
+
+ as1 = TMP_SALLOC_LIMBS (n + 1);
+ asm1 = TMP_SALLOC_LIMBS (n + 1);
+ as2 = TMP_SALLOC_LIMBS (n + 1);
+ ash = TMP_SALLOC_LIMBS (n + 1);
+ asmh = TMP_SALLOC_LIMBS (n + 1);
+
+ bs1 = TMP_SALLOC_LIMBS (n + 1);
+ bsm1 = TMP_SALLOC_LIMBS (n + 1);
+ bs2 = TMP_SALLOC_LIMBS (n + 1);
+ bsh = TMP_SALLOC_LIMBS (n + 1);
+ bsmh = TMP_SALLOC_LIMBS (n + 1);
+
+ gp = pp;
+ hp = pp + n + 1;
+
+ flags = 0;
+
+ /* Compute as1 and asm1. */
+ gp[n] = mpn_add_n (gp, a0, a2, n);
+ hp[n] = mpn_add (hp, a1, n, a3, s);
+#if HAVE_NATIVE_mpn_addsub_n
+ if (mpn_cmp (gp, hp, n + 1) < 0)
+ {
+ mpn_addsub_n (as1, asm1, hp, gp, n + 1);
+ flags ^= toom4_w3_neg;
+ }
+ else
+ {
+ mpn_addsub_n (as1, asm1, gp, hp, n + 1);
+ }
+#else
+ mpn_add_n (as1, gp, hp, n + 1);
+ if (mpn_cmp (gp, hp, n + 1) < 0)
+ {
+ mpn_sub_n (asm1, hp, gp, n + 1);
+ flags ^= toom4_w3_neg;
+ }
+ else
+ {
+ mpn_sub_n (asm1, gp, hp, n + 1);
+ }
+#endif
+
+ /* Compute as2. */
+#if HAVE_NATIVE_mpn_addlsh1_n
+ cy = mpn_addlsh1_n (as2, a2, a3, s);
+ if (s != n)
+ cy = mpn_add_1 (as2 + s, a2 + s, n - s, cy);
+ cy = 2 * cy + mpn_addlsh1_n (as2, a1, as2, n);
+ cy = 2 * cy + mpn_addlsh1_n (as2, a0, as2, n);
+#else
+ cy = mpn_lshift (as2, a3, s, 1);
+ cy += mpn_add_n (as2, a2, as2, s);
+ if (s != n)
+ cy = mpn_add_1 (as2 + s, a2 + s, n - s, cy);
+ cy = 2 * cy + mpn_lshift (as2, as2, n, 1);
+ cy += mpn_add_n (as2, a1, as2, n);
+ cy = 2 * cy + mpn_lshift (as2, as2, n, 1);
+ cy += mpn_add_n (as2, a0, as2, n);
+#endif
+ as2[n] = cy;
+
+ /* Compute ash and asmh. */
+ cy = mpn_lshift (gp, a0, n, 3); /* 8a0 */
+#if HAVE_NATIVE_mpn_addlsh1_n
+ gp[n] = cy + mpn_addlsh1_n (gp, gp, a2, n); /* 8a0 + 2a2 */
+#else
+ cy += mpn_lshift (hp, a2, n, 1); /* 2a2 */
+ gp[n] = cy + mpn_add_n (gp, gp, hp, n); /* 8a0 + 2a2 */
+#endif
+ cy = mpn_lshift (hp, a1, n, 2); /* 4a1 */
+ hp[n] = cy + mpn_add (hp, hp, n, a3, s); /* 4a1 + a3 */
+#if HAVE_NATIVE_mpn_addsub_n
+ if (mpn_cmp (gp, hp, n + 1) < 0)
+ {
+ mpn_addsub_n (ash, asmh, hp, gp, n + 1);
+ flags ^= toom4_w1_neg;
+ }
+ else
+ {
+ mpn_addsub_n (ash, asmh, gp, hp, n + 1);
+ }
+#else
+ mpn_add_n (ash, gp, hp, n + 1);
+ if (mpn_cmp (gp, hp, n + 1) < 0)
+ {
+ mpn_sub_n (asmh, hp, gp, n + 1);
+ flags ^= toom4_w1_neg;
+ }
+ else
+ {
+ mpn_sub_n (asmh, gp, hp, n + 1);
+ }
+#endif
+
+ /* Compute bs1 and bsm1. */
+ gp[n] = mpn_add_n (gp, b0, b2, n);
+ hp[n] = mpn_add (hp, b1, n, b3, t);
+#if HAVE_NATIVE_mpn_addsub_n
+ if (mpn_cmp (gp, hp, n + 1) < 0)
+ {
+ mpn_addsub_n (bs1, bsm1, hp, gp, n + 1);
+ flags ^= toom4_w3_neg;
+ }
+ else
+ {
+ mpn_addsub_n (bs1, bsm1, gp, hp, n + 1);
+ }
+#else
+ mpn_add_n (bs1, gp, hp, n + 1);
+ if (mpn_cmp (gp, hp, n + 1) < 0)
+ {
+ mpn_sub_n (bsm1, hp, gp, n + 1);
+ flags ^= toom4_w3_neg;
+ }
+ else
+ {
+ mpn_sub_n (bsm1, gp, hp, n + 1);
+ }
+#endif
+
+ /* Compute bs2. */
+#if HAVE_NATIVE_mpn_addlsh1_n
+ cy = mpn_addlsh1_n (bs2, b2, b3, t);
+ if (t != n)
+ cy = mpn_add_1 (bs2 + t, b2 + t, n - t, cy);
+ cy = 2 * cy + mpn_addlsh1_n (bs2, b1, bs2, n);
+ cy = 2 * cy + mpn_addlsh1_n (bs2, b0, bs2, n);
+#else
+ cy = mpn_lshift (bs2, b3, t, 1);
+ cy += mpn_add_n (bs2, b2, bs2, t);
+ if (t != n)
+ cy = mpn_add_1 (bs2 + t, b2 + t, n - t, cy);
+ cy = 2 * cy + mpn_lshift (bs2, bs2, n, 1);
+ cy += mpn_add_n (bs2, b1, bs2, n);
+ cy = 2 * cy + mpn_lshift (bs2, bs2, n, 1);
+ cy += mpn_add_n (bs2, b0, bs2, n);
+#endif
+ bs2[n] = cy;
+
+ /* Compute bsh and bsmh. */
+ cy = mpn_lshift (gp, b0, n, 3); /* 8b0 */
+#if HAVE_NATIVE_mpn_addlsh1_n
+ gp[n] = cy + mpn_addlsh1_n (gp, gp, b2, n); /* 8b0 + 2b2 */
+#else
+ cy += mpn_lshift (hp, b2, n, 1); /* 2b2 */
+ gp[n] = cy + mpn_add_n (gp, gp, hp, n); /* 8b0 + 2b2 */
+#endif
+ cy = mpn_lshift (hp, b1, n, 2); /* 4b1 */
+ hp[n] = cy + mpn_add (hp, hp, n, b3, t); /* 4b1 + b3 */
+#if HAVE_NATIVE_mpn_addsub_n
+ if (mpn_cmp (gp, hp, n + 1) < 0)
+ {
+ mpn_addsub_n (bsh, bsmh, hp, gp, n + 1);
+ flags ^= toom4_w1_neg;
+ }
+ else
+ {
+ mpn_addsub_n (bsh, bsmh, gp, hp, n + 1);
+ }
+#else
+ mpn_add_n (bsh, gp, hp, n + 1);
+ if (mpn_cmp (gp, hp, n + 1) < 0)
+ {
+ mpn_sub_n (bsmh, hp, gp, n + 1);
+ flags ^= toom4_w1_neg;
+ }
+ else
+ {
+ mpn_sub_n (bsmh, gp, hp, n + 1);
+ }
+#endif
+
+ ASSERT (as1[n] <= 3);
+ ASSERT (bs1[n] <= 3);
+ ASSERT (asm1[n] <= 1);
+ ASSERT (bsm1[n] <= 1);
+ ASSERT (as2[n] <= 14);
+ ASSERT (bs2[n] <= 14);
+ ASSERT (ash[n] <= 14);
+ ASSERT (bsh[n] <= 14);
+ ASSERT (asmh[n] <= 9);
+ ASSERT (bsmh[n] <= 9);
+
+#define v0 pp /* 2n */
+#define v1 (scratch + 6 * n + 6) /* 2n+1 */
+#define vm1 scratch /* 2n+1 */
+#define v2 (scratch + 2 * n + 2) /* 2n+1 */
+#define vinf (pp + 6 * n) /* s+t */
+#define vh (pp + 2 * n) /* 2n+1 */
+#define vmh (scratch + 4 * n + 4)
+#define scratch_out (scratch + 8 * n + 8)
+
+ /* vm1, 2n+1 limbs */
+ TOOM44_MUL_N_REC (vm1, asm1, bsm1, n + 1, scratch_out); /* vm1, 2n+1 limbs */
+
+ TOOM44_MUL_N_REC (v2 , as2 , bs2 , n + 1, scratch_out); /* v2, 2n+1 limbs */
+
+ if (s > t) mpn_mul (vinf, a3, s, b3, t);
+ else TOOM44_MUL_N_REC (vinf, a3, b3, s, scratch_out); /* vinf, s+t limbs */
+
+ TOOM44_MUL_N_REC (v1 , as1 , bs1 , n + 1, scratch_out); /* v1, 2n+1 limbs */
+
+ TOOM44_MUL_N_REC (vh , ash , bsh , n + 1, scratch_out);
+
+ TOOM44_MUL_N_REC (vmh, asmh, bsmh, n + 1, scratch_out);
+
+ TOOM44_MUL_N_REC (v0 , ap , bp , n , scratch_out); /* v0, 2n limbs */
+
+ mpn_toom_interpolate_7pts (pp, n, flags, vmh, vm1, v1, v2, s + t, scratch_out);
+
+ TMP_FREE;
+}
projects / msp430-gcc.git / blobdiff