| 0,0 → 1,188 |
|---|
| /* |
| * Copyright (C) 2006 Josef Cejka |
| * All rights reserved. |
| * |
| * Redistribution and use in source and binary forms, with or without |
| * modification, are permitted provided that the following conditions |
| * are met: |
| * |
| * - Redistributions of source code must retain the above copyright |
| * notice, this list of conditions and the following disclaimer. |
| * - Redistributions in binary form must reproduce the above copyright |
| * notice, this list of conditions and the following disclaimer in the |
| * documentation and/or other materials provided with the distribution. |
| * - The name of the author may not be used to endorse or promote products |
| * derived from this software without specific prior written permission. |
| * |
| * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR |
| * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES |
| * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. |
| * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, |
| * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT |
| * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, |
| * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY |
| * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT |
| * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF |
| * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. |
| */ |
| |
| #include <genarch/softint/division.h> |
| |
| #define ABSVAL(x) ( (x) > 0 ? (x) : -(x)) |
| #define SGN(x) ( (x) >= 0 ? 1 : 0 ) |
| |
| static unsigned int divandmod32(unsigned int a, unsigned int b, unsigned int *remainder) |
| { |
| unsigned int result; |
| int steps = sizeof(unsigned int) * 8; |
| |
| *remainder = 0; |
| result = 0; |
| |
| if (b == 0) { |
| /* FIXME: division by zero */ |
| return 0; |
| } |
| |
| if ( a < b) { |
| *remainder = a; |
| return 0; |
| } |
| |
| for ( ; steps > 0; steps--) { |
| /* shift one bit to remainder */ |
| *remainder = ( (*remainder) << 1) | (( a >> 31) & 0x1); |
| result <<= 1; |
| |
| if (*remainder >= b) { |
| *remainder -= b; |
| result |= 0x1; |
| } |
| a <<= 1; |
| } |
| |
| return result; |
| } |
| |
| |
| static unsigned long divandmod64(unsigned long a, unsigned long b, unsigned long *remainder) |
| { |
| unsigned long result; |
| int steps = sizeof(unsigned long) * 8; |
| |
| *remainder = 0; |
| result = 0; |
| |
| if (b == 0) { |
| /* FIXME: division by zero */ |
| return 0; |
| } |
| |
| if ( a < b) { |
| *remainder = a; |
| return 0; |
| } |
| |
| for ( ; steps > 0; steps--) { |
| /* shift one bit to remainder */ |
| *remainder = ( (*remainder) << 1) | ((a >> 63) & 0x1); |
| result <<= 1; |
| |
| if (*remainder >= b) { |
| *remainder -= b; |
| result |= 0x1; |
| } |
| a <<= 1; |
| } |
| |
| return result; |
| } |
| |
| /* 32bit integer division */ |
| int __divsi3(int a, int b) |
| { |
| unsigned int rem; |
| int result; |
| |
| result = (int)divandmod32(ABSVAL(a), ABSVAL(b), &rem); |
| |
| if ( SGN(a) == SGN(b)) return result; |
| return -result; |
| } |
| |
| /* 64bit integer division */ |
| long __divdi3(long a, long b) |
| { |
| unsigned long rem; |
| long result; |
| |
| result = (long)divandmod64(ABSVAL(a), ABSVAL(b), &rem); |
| |
| if ( SGN(a) == SGN(b)) return result; |
| return -result; |
| } |
| |
| /* 32bit unsigned integer division */ |
| unsigned int __udivsi3(unsigned int a, unsigned int b) |
| { |
| unsigned int rem; |
| return divandmod32(a, b, &rem); |
| } |
| |
| /* 64bit unsigned integer division */ |
| unsigned long __udivdi3(unsigned long a, unsigned long b) |
| { |
| unsigned long rem; |
| return divandmod64(a, b, &rem); |
| } |
| |
| /* 32bit remainder of the signed division */ |
| int __modsi3(int a, int b) |
| { |
| unsigned int rem; |
| divandmod32(a, b, &rem); |
| |
| /* if divident is negative, remainder must be too */ |
| if (!(SGN(a))) { |
| return -((int)rem); |
| } |
| |
| return (int)rem; |
| } |
| |
| /* 64bit remainder of the signed division */ |
| long __moddi3(long a, long b) |
| { |
| unsigned long rem; |
| divandmod64(a, b, &rem); |
| |
| /* if divident is negative, remainder must be too */ |
| if (!(SGN(a))) { |
| return -((long)rem); |
| } |
| |
| return (long)rem; |
| } |
| |
| /* 32bit remainder of the unsigned division */ |
| unsigned int __umodsi3(unsigned int a, unsigned int b) |
| { |
| unsigned int rem; |
| divandmod32(a, b, &rem); |
| return rem; |
| } |
| |
| /* 64bit remainder of the unsigned division */ |
| unsigned long __umoddi3(unsigned long a, unsigned long b) |
| { |
| unsigned long rem; |
| divandmod64(a, b, &rem); |
| return rem; |
| } |
| |
| unsigned long __udivmoddi3(unsigned long a, unsigned long b, unsigned long *c) |
| { |
| return divandmod64(a, b, c); |
| } |
| |
| |