sovereign-rf/hackrf
1
0
Fork 0
Code Issues Pull requests Projects Releases Packages Wiki Activity Actions

Add multiply & divide implementations for 128-bit unsigned integers.

Browse source
This commit is contained in:
Martin Ling 2026-06-30 01:56:12 +01:00
parent 74c3b730fa
commit dda161cb1f
3 changed files with 121 additions and 0 deletions
Download patch file Download diff file Expand all files Collapse all files

88
firmware/common/u128.c Normal file
View file

@ -0,0 +1,88 @@
/*
* Copyright 2026 Great Scott Gadgets <info@greatscottgadgets.com>
*
* This file is part of HackRF.
*
* 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, 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; see the file COPYING. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street,
* Boston, MA 02110-1301, USA.
*/
#include "u128.h"
/* From https://stackoverflow.com/a/58381061 */
u128 u128_multiply(uint64_t lhs, uint64_t rhs)
{
uint64_t lo_lo = (lhs & 0xFFFFFFFF) * (rhs & 0xFFFFFFFF);
uint64_t hi_lo = (lhs >> 32) * (rhs & 0xFFFFFFFF);
uint64_t lo_hi = (lhs & 0xFFFFFFFF) * (rhs >> 32);
uint64_t hi_hi = (lhs >> 32) * (rhs >> 32);
uint64_t cross = ((lo_lo >> 32) + (hi_lo & 0xFFFFFFFF) + lo_hi);
return (u128){
.hi = ((hi_lo >> 32) + (cross >> 32) + hi_hi),
.lo = ((cross << 32) | (lo_lo & 0xFFFFFFFF)),
};
}
/* From https://stackoverflow.com/a/70052545 */
/* clang-format off */
#define SUBCcc(a,b,cy,t0,t1,t2) \
(t0=(b)+cy, t1=(a), cy=t0<cy, t2=t1<t0, cy=cy+t2, t1-t0)
#define SUBcc(a,b,cy,t0,t1) \
(t0=(b), t1=(a), cy=t1<t0, t1-t0)
#define SUBC(a,b,cy,t0,t1) \
(t0=(b)+cy, t1=(a), t1-t0)
#define ADDCcc(a,b,cy,t0,t1) \
(t0=(b)+cy, t1=(a), cy=t0<cy, t0=t0+t1, t1=t0<t1, cy=cy+t1, t0=t0)
#define ADDcc(a,b,cy,t0,t1) \
(t0=(b), t1=(a), t0=t0+t1, cy=t0<t1, t0=t0)
#define ADDC(a,b,cy,t0,t1) \
(t0=(b)+cy, t1=(a), t0+t1)
/* clang-format on */
u128 u128_divide(u128 dvnd, u128 dvsr)
{
u128 quot, rem, tmp;
uint64_t cy, t0, t1, t2;
quot.hi = dvnd.hi;
quot.lo = dvnd.lo;
rem.hi = 0;
rem.lo = 0;
for (int i = 0; i < 128; i++) {
quot.lo = ADDcc(quot.lo, quot.lo, cy, t0, t1);
quot.hi = ADDCcc(quot.hi, quot.hi, cy, t0, t1);
rem.lo = ADDCcc(rem.lo, rem.lo, cy, t0, t1);
rem.hi = ADDC(rem.hi, rem.hi, cy, t0, t1);
tmp.lo = SUBcc(rem.lo, dvsr.lo, cy, t0, t1);
tmp.hi = SUBCcc(rem.hi, dvsr.hi, cy, t0, t1, t2);
if (!cy) { // remainder >= divisor
rem.lo = tmp.lo;
rem.hi = tmp.hi;
quot.lo |= 1;
}
}
return quot;
}

32
firmware/common/u128.h Normal file
View file

@ -0,0 +1,32 @@
/*
* Copyright 2026 Great Scott Gadgets <info@greatscottgadgets.com>
*
* This file is part of HackRF.
*
* 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, 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; see the file COPYING. If not, write to
* the Free Software Foundation, Inc., 51 Franklin Street,
* Boston, MA 02110-1301, USA.
*/
#pragma once
#include <stdint.h>
typedef struct {
uint64_t hi;
uint64_t lo;
} u128;
u128 u128_multiply(uint64_t a, uint64_t b);
u128 u128_divide(u128 dvnd, u128 dvsr);

1
firmware/hackrf-common.cmake
View file

@ -203,6 +203,7 @@ macro(DeclareTargets)
${PATH_HACKRF_FIRMWARE_COMMON}/adc.c
${PATH_HACKRF_FIRMWARE_COMMON}/da7219.c
${PATH_HACKRF_FIRMWARE_COMMON}/max283x.c
${PATH_HACKRF_FIRMWARE_COMMON}/u128.c
)
if(BOARD STREQUAL "RAD1O")