/* $OpenBSD: reg.c,v 1.3 2016/08/14 23:01:13 guenther Exp $ */ /* * Copyright (c) 2003 Jason L. Wright (jason@thought.net) * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. 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. * * 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 #include int64_t asm_popc(int64_t); int64_t c_popc(int64_t); int test_it(int64_t); int test_ones(void); int main(void); int64_t asm_popc(int64_t v) { asm("popc %1, %0" : "=r" (v) : "r" (v)); return (v); } int64_t c_popc(int64_t v) { int64_t bit, r; for (bit = 1, r = 0; bit; bit <<= 1) if (v & bit) r++; return (r); } int test_it(int64_t v) { int64_t tc, ta; tc = c_popc(v); ta = asm_popc(v); if (tc == ta) return (0); printf("%lld: C(%lld) ASM(%lld)\n", v, tc, ta); return (1); } int test_ones(void) { int64_t v; int i, r = 0; for (i = 0; i < 64; i++) { v = 1LL << i; if (c_popc(v) != 1) { printf("ONES popc(%lld) != 1\n", v); r = 1; } if (test_it(v)) r = 1; } return (r); } int main() { int r = 0; if (test_ones()) r = 1; return (r); }