| 1 | /****************************************************************************** |
| 2 | * Arachnoid Graphics Plugin for Mupen64Plus |
| 3 | * http://bitbucket.org/wahrhaft/mupen64plus-video-arachnoid/ |
| 4 | * |
| 5 | * Copyright (C) 2007 Kristofer Karlsson, Rickard Niklasson |
| 6 | * |
| 7 | * This program is free software; you can redistribute it and/or |
| 8 | * modify it under the terms of the GNU General Public License |
| 9 | * as published by the Free Software Foundation; either version 2 |
| 10 | * of the License, or (at your option) any later version. |
| 11 | * |
| 12 | * This program is distributed in the hope that it will be useful, |
| 13 | * but WITHOUT ANY WARRANTY; without even the implied warranty of |
| 14 | * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the |
| 15 | * GNU General Public License for more details. |
| 16 | * |
| 17 | * You should have received a copy of the GNU General Public License |
| 18 | * along with this program; if not, write to the Free Software |
| 19 | * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA. |
| 20 | *****************************************************************************/ |
| 21 | |
| 22 | //***************************************************************************** |
| 23 | // |
| 24 | // NOTE THAT THIS FILE IS BASED ON MATERIAL FROM glN64. |
| 25 | // http://gln64.emulation64.com/ |
| 26 | // |
| 27 | //***************************************************************************** |
| 28 | |
| 29 | #include "CombinerStructs.h" |
| 30 | |
| 31 | //----------------------------------------------------------------------------- |
| 32 | //* Merge Stages |
| 33 | //! Try two merge to stages into one |
| 34 | //! From glN64 |
| 35 | //----------------------------------------------------------------------------- |
| 36 | void mergeStages(Combiner* c) |
| 37 | { |
| 38 | |
| 39 | // If all we have is a load in the first stage we can just replace |
| 40 | // each occurance of COMBINED in the second stage with it |
| 41 | if ((c->stage[0].numOps == 1) && (c->stage[0].op[0].op == LOAD)) |
| 42 | { |
| 43 | int combined = c->stage[0].op[0].param1; |
| 44 | |
| 45 | for (int i = 0; i < c->stage[1].numOps; i++) |
| 46 | { |
| 47 | c->stage[0].op[i].op = c->stage[1].op[i].op; |
| 48 | c->stage[0].op[i].param1 = (c->stage[1].op[i].param1 == COMBINED) ? combined : c->stage[1].op[i].param1; |
| 49 | c->stage[0].op[i].param2 = (c->stage[1].op[i].param2 == COMBINED) ? combined : c->stage[1].op[i].param2; |
| 50 | c->stage[0].op[i].param3 = (c->stage[1].op[i].param3 == COMBINED) ? combined : c->stage[1].op[i].param3; |
| 51 | } |
| 52 | |
| 53 | c->stage[0].numOps = c->stage[1].numOps; |
| 54 | c->numStages = 1; |
| 55 | } |
| 56 | // We can't do any merging on an interpolation |
| 57 | else if (c->stage[1].op[0].op != INTERPOLATE) |
| 58 | { |
| 59 | int numCombined = 0; |
| 60 | |
| 61 | // See how many times the first stage is used in the second one |
| 62 | for (int i = 0; i < c->stage[1].numOps; i++) |
| 63 | if (c->stage[1].op[i].param1 == COMBINED) |
| 64 | numCombined++; |
| 65 | |
| 66 | // If it's not used, just replace the first stage with the second |
| 67 | if (numCombined == 0) |
| 68 | { |
| 69 | for (int i = 0; i < c->stage[1].numOps; i++) |
| 70 | { |
| 71 | c->stage[0].op[i].op = c->stage[1].op[i].op; |
| 72 | c->stage[0].op[i].param1 = c->stage[1].op[i].param1; |
| 73 | c->stage[0].op[i].param2 = c->stage[1].op[i].param2; |
| 74 | c->stage[0].op[i].param3 = c->stage[1].op[i].param3; |
| 75 | } |
| 76 | c->stage[0].numOps = c->stage[1].numOps; |
| 77 | |
| 78 | c->numStages = 1; |
| 79 | } |
| 80 | // If it's only used once |
| 81 | else if (numCombined == 1) |
| 82 | { |
| 83 | // It's only used in the load, so stack on the ops from stage 2 on stage 1 |
| 84 | if (c->stage[1].op[0].param1 == COMBINED) |
| 85 | { |
| 86 | for (int i = 1; i < c->stage[1].numOps; i++) |
| 87 | { |
| 88 | c->stage[0].op[c->stage[0].numOps].op = c->stage[1].op[i].op; |
| 89 | c->stage[0].op[c->stage[0].numOps].param1 = c->stage[1].op[i].param1; |
| 90 | c->stage[0].numOps++; |
| 91 | } |
| 92 | |
| 93 | c->numStages = 1; |
| 94 | } |
| 95 | // Otherwise, if it's used in the second op, and that op isn't SUB |
| 96 | // we can switch the parameters so it works out to tack the ops onto stage 1 |
| 97 | else if ((c->stage[1].op[1].param1 == COMBINED) && (c->stage[1].op[1].op != SUB)) |
| 98 | { |
| 99 | c->stage[0].op[c->stage[0].numOps].op = c->stage[1].op[1].op; |
| 100 | c->stage[0].op[c->stage[0].numOps].param1 = c->stage[1].op[0].param1; |
| 101 | c->stage[0].numOps++; |
| 102 | |
| 103 | // If there's another op, tack it onto stage 1 too |
| 104 | if (c->stage[1].numOps > 2) |
| 105 | { |
| 106 | c->stage[0].op[c->stage[0].numOps].op = c->stage[1].op[2].op; |
| 107 | c->stage[0].op[c->stage[0].numOps].param1 = c->stage[1].op[2].param1; |
| 108 | c->stage[0].numOps++; |
| 109 | } |
| 110 | |
| 111 | c->numStages = 1; |
| 112 | } |
| 113 | } |
| 114 | } |
| 115 | } |