/*      $NetBSD: maskbits.h,v 1.2 2025/05/31 18:11:50 tsutsui 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 (/* CONSTCOND */ 0)

#define FASTGETBITS(psrc, x, w, dst)                                    \
   __asm ("bfextu %3{%1:%2},%0"                                        \
       : "=d" (dst) : "di" (x), "di" (w), "o" (*(uint8_t *)(psrc)))

#define FASTPUTBITS(src, x, w, pdst)                                    \
   __asm ("bfins %3,%0{%1:%2}"                                         \
       : "=o" (*(uint8_t *)(pdst))                                     \
       : "di" (x), "di" (w), "d" (src))

#define getandputrop(psrc, srcbit, dstbit, width, pdst, rop)            \
do {                                                                    \
       uint32_t _tmpsrc, _tmpdst;                                      \
       FASTGETBITS(pdst, dstbit, width, _tmpdst);                      \
       FASTGETBITS(psrc, srcbit, width, _tmpsrc);                      \
       DoRop(_tmpdst, rop, _tmpsrc, _tmpdst);                          \
       FASTPUTBITS(_tmpdst, dstbit, width, pdst);                      \
} while (/* CONSTCOND */ 0)

#define getandputrop0(psrc, srcbit, width, pdst, rop)                   \
       getandputrop(psrc, srcbit, 0, width, pdst, rop)

#define getunalignedword(psrc, x, dst)                                  \
do {                                                                    \
       uint32_t _tmp;                                                  \
       FASTGETBITS(psrc, x, 32, _tmp);                                 \
       dst = _tmp;                                                     \
} while (/* CONSTCOND */ 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 {                                                                    \
       if (alu == RR_COPY)                                             \
               result = fnCOPY(src, dst);                              \
       else {                                                          \
               switch (alu) {                                          \
               case RR_CLEAR:                                          \
                       result = fnCLEAR(src, dst);                     \
                       break;                                          \
               case RR_XOR:                                            \
                       result = fnXOR(src, dst);                       \
                       break;                                          \
               case RR_COPYINVERTED:                                   \
                       result = fnCOPYINVERTED(src, dst);              \
                       break;                                          \
               }                                                       \
       }                                                               \
} while (/* CONSTCOND */ 0)

You are viewing proxied material from ftp.icm.edu.pl. The copyright of proxied material belongs to its original authors. Any comments or complaints in relation to proxied material should be directed to the original authors of the content concerned. Please see the disclaimer for more details.