diff options
| -rw-r--r-- | arch/blackfin/lib/muldi3.S | 68 | ||||
| -rw-r--r-- | arch/blackfin/lib/muldi3.c | 99 |
2 files changed, 68 insertions, 99 deletions
diff --git a/arch/blackfin/lib/muldi3.S b/arch/blackfin/lib/muldi3.S new file mode 100644 index 00000000000..abde120ee23 --- /dev/null +++ b/arch/blackfin/lib/muldi3.S @@ -0,0 +1,68 @@ +.align 2 +.global ___muldi3; +.type ___muldi3, STT_FUNC; + +#ifdef CONFIG_ARITHMETIC_OPS_L1 +.section .l1.text +#else +.text +#endif + +/* + R1:R0 * R3:R2 + = R1.h:R1.l:R0.h:R0.l * R3.h:R3.l:R2.h:R2.l +[X] = (R1.h * R3.h) * 2^96 +[X] + (R1.h * R3.l + R1.l * R3.h) * 2^80 +[X] + (R1.h * R2.h + R1.l * R3.l + R3.h * R0.h) * 2^64 +[T1] + (R1.h * R2.l + R3.h * R0.l + R1.l * R2.h + R3.l * R0.h) * 2^48 +[T2] + (R1.l * R2.l + R3.l * R0.l + R0.h * R2.h) * 2^32 +[T3] + (R0.l * R2.h + R2.l * R0.h) * 2^16 +[T4] + (R0.l * R2.l) + + We can discard the first three lines marked "X" since we produce + only a 64 bit result. So, we need ten 16-bit multiplies. + + Individual mul-acc results: +[E1] = R1.h * R2.l + R3.h * R0.l + R1.l * R2.h + R3.l * R0.h +[E2] = R1.l * R2.l + R3.l * R0.l + R0.h * R2.h +[E3] = R0.l * R2.h + R2.l * R0.h +[E4] = R0.l * R2.l + + We also need to add high parts from lower-level results to higher ones: + E[n]c = E[n] + (E[n+1]c >> 16), where E4c := E4 + + One interesting property is that all parts of the result that depend + on the sign of the multiplication are discarded. Those would be the + multiplications involving R1.h and R3.h, but only the top 16 bit of + the 32 bit result depend on the sign, and since R1.h and R3.h only + occur in E1, the top half of these results is cut off. + So, we can just use FU mode for all of the 16-bit multiplies, and + ignore questions of when to use mixed mode. */ + +___muldi3: + /* [SP] technically is part of the caller's frame, but we can + use it as scratch space. */ + A0 = R2.H * R1.L, A1 = R2.L * R1.H (FU) || R3 = [SP + 12]; /* E1 */ + A0 += R3.H * R0.L, A1 += R3.L * R0.H (FU) || [SP] = R4; /* E1 */ + A0 += A1; /* E1 */ + R4 = A0.w; + A0 = R0.l * R3.l (FU); /* E2 */ + A0 += R2.l * R1.l (FU); /* E2 */ + + A1 = R2.L * R0.L (FU); /* E4 */ + R3 = A1.w; + A1 = A1 >> 16; /* E3c */ + A0 += R2.H * R0.H, A1 += R2.L * R0.H (FU); /* E2, E3c */ + A1 += R0.L * R2.H (FU); /* E3c */ + R0 = A1.w; + A1 = A1 >> 16; /* E2c */ + A0 += A1; /* E2c */ + R1 = A0.w; + + /* low(result) = low(E3c):low(E4) */ + R0 = PACK (R0.l, R3.l); + /* high(result) = E2c + (E1 << 16) */ + R1.h = R1.h + R4.l (NS) || R4 = [SP]; + RTS; + +.size ___muldi3, .-___muldi3 diff --git a/arch/blackfin/lib/muldi3.c b/arch/blackfin/lib/muldi3.c deleted file mode 100644 index 303d0c6a6db..00000000000 --- a/arch/blackfin/lib/muldi3.c +++ /dev/null @@ -1,99 +0,0 @@ -/* - * File: arch/blackfin/lib/muldi3.c - * Based on: - * Author: - * - * Created: - * Description: - * - * Modified: - * Copyright 2004-2006 Analog Devices Inc. - * - * Bugs: Enter bugs at http://blackfin.uclinux.org/ - * - * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2 of the License, or - * (at your option) any later version. - * - * This program 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 General Public License for more details. - * - * You should have received a copy of the GNU General Public License - * along with this program; if not, see the file COPYING, or write - * to the Free Software Foundation, Inc., - * 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA - */ - -#ifndef SI_TYPE_SIZE -#define SI_TYPE_SIZE 32 -#endif -#define __ll_b (1L << (SI_TYPE_SIZE / 2)) -#define __ll_lowpart(t) ((usitype) (t) % __ll_b) -#define __ll_highpart(t) ((usitype) (t) / __ll_b) -#define BITS_PER_UNIT 8 - -#if !defined(umul_ppmm) -#define umul_ppmm(w1, w0, u, v) \ - do { \ - usitype __x0, __x1, __x2, __x3; \ - usitype __ul, __vl, __uh, __vh; \ - \ - __ul = __ll_lowpart (u); \ - __uh = __ll_highpart (u); \ - __vl = __ll_lowpart (v); \ - __vh = __ll_highpart (v); \ - \ - __x0 = (usitype) __ul * __vl; \ - __x1 = (usitype) __ul * __vh; \ - __x2 = (usitype) __uh * __vl; \ - __x3 = (usitype) __uh * __vh; \ - \ - __x1 += __ll_highpart (__x0);/* this can't give carry */ \ - __x1 += __x2; /* but this indeed can */ \ - if (__x1 < __x2) /* did we get it? */ \ - __x3 += __ll_b; /* yes, add it in the proper pos. */ \ - \ - (w1) = __x3 + __ll_highpart (__x1); \ - (w0) = __ll_lowpart (__x1) * __ll_b + __ll_lowpart (__x0); \ - } while (0) -#endif - -#if !defined(__umulsidi3) -#define __umulsidi3(u, v) \ - ({diunion __w; \ - umul_ppmm (__w.s.high, __w.s.low, u, v); \ - __w.ll; }) -#endif - -typedef unsigned int usitype __attribute__ ((mode(SI))); -typedef int sitype __attribute__ ((mode(SI))); -typedef int ditype __attribute__ ((mode(DI))); -typedef int word_type __attribute__ ((mode(__word__))); - -struct distruct { - sitype low, high; -}; -typedef union { - struct distruct s; - ditype ll; -} diunion; - -#ifdef CONFIG_ARITHMETIC_OPS_L1 -ditype __muldi3(ditype u, ditype v)__attribute__((l1_text)); -#endif - -ditype __muldi3(ditype u, ditype v) -{ - diunion w; - diunion uu, vv; - - uu.ll = u, vv.ll = v; - w.ll = __umulsidi3(uu.s.low, vv.s.low); - w.s.high += ((usitype) uu.s.low * (usitype) vv.s.high - + (usitype) uu.s.high * (usitype) vv.s.low); - - return w.ll; -} |