1 /* $NetBSD: maskbits.h,v 1.5 2003/08/07 16:27:33 agc Exp $ */ 2 3 /*- 4 * Copyright (c) 1994 5 * The Regents of the University of California. All rights reserved. 6 * 7 * Redistribution and use in source and binary forms, with or without 8 * modification, are permitted provided that the following conditions 9 * are met: 10 * 1. Redistributions of source code must retain the above copyright 11 * notice, this list of conditions and the following disclaimer. 12 * 2. Redistributions in binary form must reproduce the above copyright 13 * notice, this list of conditions and the following disclaimer in the 14 * documentation and/or other materials provided with the distribution. 15 * 3. Neither the name of the University nor the names of its contributors 16 * may be used to endorse or promote products derived from this software 17 * without specific prior written permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND 20 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE 21 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE 22 * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE 23 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL 24 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS 25 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) 26 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 27 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY 28 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF 29 * SUCH DAMAGE. 30 * 31 * @(#)maskbits.h 8.2 (Berkeley) 3/21/94 32 */ 33 34 /* 35 * Derived from X11R4 36 */ 37 38 /* the following notes use the following conventions: 39 SCREEN LEFT SCREEN RIGHT 40 in this file and maskbits.c, left and right refer to screen coordinates, 41 NOT bit numbering in registers. 42 43 starttab[n] 44 bits[0,n-1] = 0 bits[n,31] = 1 45 endtab[n] = 46 bits[0,n-1] = 1 bits[n,31] = 0 47 48 maskbits(x, w, startmask, endmask, nlw) 49 for a span of width w starting at position x, returns 50 a mask for ragged bits at start, mask for ragged bits at end, 51 and the number of whole longwords between the ends. 52 53 */ 54 55 #define maskbits(x, w, startmask, endmask, nlw) \ 56 startmask = starttab[(x)&0x1f]; \ 57 endmask = endtab[((x)+(w)) & 0x1f]; \ 58 if (startmask) \ 59 nlw = (((w) - (32 - ((x)&0x1f))) >> 5); \ 60 else \ 61 nlw = (w) >> 5; 62 63 #define FASTGETBITS(psrc, x, w, dst) \ 64 asm ("bfextu %3{%1:%2},%0" \ 65 : "=d" (dst) : "di" (x), "di" (w), "o" (*(char *)(psrc))) 66 67 #define FASTPUTBITS(src, x, w, pdst) \ 68 asm ("bfins %3,%0{%1:%2}" \ 69 : "=o" (*(char *)(pdst)) \ 70 : "di" (x), "di" (w), "d" (src)) 71 72 #define getandputrop(psrc, srcbit, dstbit, width, pdst, rop) \ 73 { \ 74 unsigned int _tmpsrc, _tmpdst; \ 75 FASTGETBITS(pdst, dstbit, width, _tmpdst); \ 76 FASTGETBITS(psrc, srcbit, width, _tmpsrc); \ 77 DoRop(_tmpdst, rop, _tmpsrc, _tmpdst); \ 78 FASTPUTBITS(_tmpdst, dstbit, width, pdst); \ 79 } 80 81 #define getandputrop0(psrc, srcbit, width, pdst, rop) \ 82 getandputrop(psrc, srcbit, 0, width, pdst, rop) 83 84 #define getunalignedword(psrc, x, dst) { \ 85 int _tmp; \ 86 FASTGETBITS(psrc, x, 32, _tmp); \ 87 dst = _tmp; \ 88 } 89 90 #define fnCLEAR(src, dst) (0) 91 #define fnCOPY(src, dst) (src) 92 #define fnXOR(src, dst) (src ^ dst) 93 #define fnCOPYINVERTED(src, dst)(~src) 94 95 #define DoRop(result, alu, src, dst) \ 96 { \ 97 if (alu == RR_COPY) \ 98 result = fnCOPY (src, dst); \ 99 else \ 100 switch (alu) \ 101 { \ 102 case RR_CLEAR: \ 103 result = fnCLEAR (src, dst); \ 104 break; \ 105 case RR_XOR: \ 106 result = fnXOR (src, dst); \ 107 break; \ 108 case RR_COPYINVERTED: \ 109 result = fnCOPYINVERTED (src, dst); \ 110 break; \ 111 } \ 112 } 113