/* $NetBSD: rasops_masks.h,v 1.8.36.1 2019/08/15 12:21:27 martin Exp $ */ /*- * Copyright (c) 1999 The NetBSD Foundation, Inc. * All rights reserved. * * This code is derived from software contributed to The NetBSD Foundation * by Andrew Doran. * * 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 NETBSD FOUNDATION, INC. 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 FOUNDATION 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. */ #ifndef _RASOPS_MASKS_H_ #define _RASOPS_MASKS_H_ 1 #include #include /* * Convenience macros. To get around the problem of dealing with properly * ordered bits on little-endian machines, we just convert everything to * big-endian and back again when we're done. * * MBL: move bits left * MBR: move bits right * MBE: make big-endian */ #if BYTE_ORDER == BIG_ENDIAN #define MBL(x,y) ((y) > 31 ? 0 : (x) << (y)) #define MBR(x,y) ((y) > 31 ? 0 : (x) >> (y)) #define MBE(x) (x) #else #define MBL(x,y) ((y) > 31 ? 0 : MBE(MBE(x) << (y))) #define MBR(x,y) ((y) > 31 ? 0 : MBE(MBE(x) >> (y))) #define MBE(x) ( (((x) & 0x000000FFU) << 24) \ | (((x) & 0x0000FF00U) << 8) \ | (((x) & 0x00FF0000U) >> 8) \ | (((x) & 0xFF000000U) >> 24) ) #endif /* * Using GETBITS() and PUTBITS() inside a loop mightn't be such a good idea. * There's probably some CSE and strength-reduction that the compiler won't * even think about - really should have a few assumptions/separate cases. */ /* Get a number of bits ( <= 32 ) from *sp and store in dw */ #define GETBITS(sp, x, w, dw) do { \ dw = MBL(*(sp), (x)); \ if (((x) + (w)) > 32) \ dw |= (MBR((sp)[1], 32 - (x))); \ } while (0 /* CONSTCOND */) /* Put a number of bits ( <= 32 ) from sw to *dp */ #define PUTBITS(sw, x, w, dp) do { \ int n = (x) + (w) - 32; \ if (n <= 0) { \ uint32_t mask = rasops_pmask[(x) & 31][(w) & 31]; \ *(dp) = (*(dp) & ~mask) | (MBR(sw, x) & mask); \ } else { \ *(dp) = (*(dp) & rasops_rmask[x]) | (MBR(sw, x)); \ (dp)[1] = ((dp)[1] & rasops_rmask[n]) | \ (MBL(sw, 32-(x)) & rasops_lmask[n]); \ } \ } while (0 /* CONSTCOND */) /* rasops_masks.c */ extern const uint32_t rasops_lmask[32 + 1]; extern const uint32_t rasops_rmask[32 + 1]; extern const uint32_t rasops_pmask[32][32]; #endif /* _RASOPS_MASKS_H_ */