/* $OpenBSD: maskbits.h,v 1.5 2005/01/14 22:39:26 miod Exp $ */ /* $NetBSD: maskbits.h,v 1.3 1997/03/31 07:37:28 scottr Exp $ */ /*- * Copyright (c) 1994 * The Regents of the University of California. 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. * 3. Neither the name of the University nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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. * * @(#)maskbits.h 8.2 (Berkeley) 3/21/94 */ /* * Derived from X11R4 */ /* the following notes use the following conventions: SCREEN LEFT SCREEN RIGHT in this file and maskbits.c, left and right refer to screen coordinates, NOT bit numbering in registers. starttab[n] bits[0,n-1] = 0 bits[n,31] = 1 endtab[n] = bits[0,n-1] = 1 bits[n,31] = 0 maskbits(x, w, startmask, endmask, nlw) for a span of width w starting at position x, returns a mask for ragged bits at start, mask for ragged bits at end, and the number of whole longwords between the ends. */ #define maskbits(x, w, startmask, endmask, nlw) \ do { \ startmask = starttab[(x) & 0x1f]; \ endmask = endtab[((x) + (w)) & 0x1f]; \ if (startmask) \ nlw = (((w) - (32 - ((x) & 0x1f))) >> 5); \ else \ nlw = (w) >> 5; \ } while (0) #define FASTGETBITS(psrc, x, w, dst) \ asm ("bfextu %3{%1:%2},%0" \ : "=d" (dst) : "di" (x), "di" (w), "o" (*(char *)(psrc))) #define FASTPUTBITS(src, x, w, pdst) \ asm ("bfins %3,%0{%1:%2}" \ : "=o" (*(char *)(pdst)) \ : "di" (x), "di" (w), "d" (src), "0" (*(char *) (pdst))) #define getandputrop(psrc, srcbit, dstbit, width, pdst, rop) \ do { \ unsigned int _tmpsrc, _tmpdst; \ FASTGETBITS(pdst, dstbit, width, _tmpdst); \ FASTGETBITS(psrc, srcbit, width, _tmpsrc); \ DoRop(_tmpdst, rop, _tmpsrc, _tmpdst); \ FASTPUTBITS(_tmpdst, dstbit, width, pdst); \ } while (0) #define getandputrop0(psrc, srcbit, width, pdst, rop) \ getandputrop(psrc, srcbit, 0, width, pdst, rop) #define getunalignedword(psrc, x, dst) \ do { \ int _tmp; \ FASTGETBITS(psrc, x, 32, _tmp); \ dst = _tmp; \ } while (0) #define fnCLEAR(src, dst) (0) #define fnCOPY(src, dst) (src) #define fnXOR(src, dst) ((src) ^ (dst)) #define fnCOPYINVERTED(src, dst) (~(src)) #define DoRop(result, alu, src, dst) \ do { \ switch (alu) { \ case RR_CLEAR: \ default: \ result = fnCLEAR(src, dst); \ break; \ case RR_COPY: \ result = fnCOPY(src, dst); \ break; \ case RR_XOR: \ result = fnXOR(src, dst); \ break; \ case RR_COPYINVERTED: \ result = fnCOPYINVERTED(src, dst); \ break; \ } \ } while (0)