| 1 | /* $NetBSD: rasops_masks.h,v 1.8 2013/12/02 14:05:51 tsutsui Exp $ */ |
| 2 | |
| 3 | /*- |
| 4 | * Copyright (c) 1999 The NetBSD Foundation, Inc. |
| 5 | * All rights reserved. |
| 6 | * |
| 7 | * This code is derived from software contributed to The NetBSD Foundation |
| 8 | * by Andrew Doran. |
| 9 | * |
| 10 | * Redistribution and use in source and binary forms, with or without |
| 11 | * modification, are permitted provided that the following conditions |
| 12 | * are met: |
| 13 | * 1. Redistributions of source code must retain the above copyright |
| 14 | * notice, this list of conditions and the following disclaimer. |
| 15 | * 2. Redistributions in binary form must reproduce the above copyright |
| 16 | * notice, this list of conditions and the following disclaimer in the |
| 17 | * documentation and/or other materials provided with the distribution. |
| 18 | * |
| 19 | * THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. AND CONTRIBUTORS |
| 20 | * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED |
| 21 | * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR |
| 22 | * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE FOUNDATION OR CONTRIBUTORS |
| 23 | * BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR |
| 24 | * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF |
| 25 | * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS |
| 26 | * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN |
| 27 | * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) |
| 28 | * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE |
| 29 | * POSSIBILITY OF SUCH DAMAGE. |
| 30 | */ |
| 31 | |
| 32 | #ifndef _RASOPS_MASKS_H_ |
| 33 | #define _RASOPS_MASKS_H_ 1 |
| 34 | |
| 35 | #include <sys/types.h> |
| 36 | #include <machine/endian.h> |
| 37 | |
| 38 | /* |
| 39 | * Convenience macros. To get around the problem of dealing with properly |
| 40 | * ordered bits on little-endian machines, we just convert everything to |
| 41 | * big-endian and back again when we're done. |
| 42 | * |
| 43 | * MBL: move bits left |
| 44 | * MBR: move bits right |
| 45 | * MBE: make big-endian |
| 46 | */ |
| 47 | #if BYTE_ORDER == BIG_ENDIAN |
| 48 | |
| 49 | #define MBL(x,y) ((y) > 31 ? 0 : (x) << (y)) |
| 50 | #define MBR(x,y) ((y) > 31 ? 0 : (x) >> (y)) |
| 51 | #define MBE(x) (x) |
| 52 | |
| 53 | #else |
| 54 | |
| 55 | #define MBL(x,y) ((y) > 31 ? 0 : MBE(MBE(x) << (y))) |
| 56 | #define MBR(x,y) ((y) > 31 ? 0 : MBE(MBE(x) >> (y))) |
| 57 | #define MBE(x) ( (((x) & 0x000000FFU) << 24) \ |
| 58 | | (((x) & 0x0000FF00U) << 8) \ |
| 59 | | (((x) & 0x00FF0000U) >> 8) \ |
| 60 | | (((x) & 0xFF000000U) >> 24) ) |
| 61 | #endif |
| 62 | |
| 63 | /* |
| 64 | * Using GETBITS() and PUTBITS() inside a loop mightn't be such a good idea. |
| 65 | * There's probably some CSE and strength-reduction that the compiler won't |
| 66 | * even think about - really should have a few assumptions/separate cases. |
| 67 | */ |
| 68 | |
| 69 | /* Get a number of bits ( <= 32 ) from *sp and store in dw */ |
| 70 | #define GETBITS(sp, x, w, dw) do { \ |
| 71 | dw = MBL(*(sp), (x)); \ |
| 72 | if (((x) + (w)) > 32) \ |
| 73 | dw |= (MBR((sp)[1], 32 - (x))); \ |
| 74 | } while(0); |
| 75 | |
| 76 | /* Put a number of bits ( <= 32 ) from sw to *dp */ |
| 77 | #define PUTBITS(sw, x, w, dp) do { \ |
| 78 | int n = (x) + (w) - 32; \ |
| 79 | \ |
| 80 | if (n <= 0) { \ |
| 81 | n = rasops_pmask[x & 31][w & 31]; \ |
| 82 | *(dp) = (*(dp) & ~n) | (MBR(sw, x) & n); \ |
| 83 | } else { \ |
| 84 | *(dp) = (*(dp) & rasops_rmask[x]) | (MBR((sw), x)); \ |
| 85 | (dp)[1] = ((dp)[1] & rasops_rmask[n]) | \ |
| 86 | (MBL(sw, 32-(x)) & rasops_lmask[n]); \ |
| 87 | } \ |
| 88 | } while(0); |
| 89 | |
| 90 | /* rasops_masks.c */ |
| 91 | extern const uint32_t rasops_lmask[32+1]; |
| 92 | extern const uint32_t rasops_rmask[32+1]; |
| 93 | extern const uint32_t rasops_pmask[32][32]; |
| 94 | |
| 95 | #endif /* _RASOPS_MASKS_H_ */ |
| 96 | |