src/gallium/drivers/r300/compiler/r300_fragprog_swizzle.c

   1 /*
   2  * Copyright (C) 2008 Nicolai Haehnle.
   3  *
   4  * All Rights Reserved.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining
   7  * a copy of this software and associated documentation files (the
   8  * "Software"), to deal in the Software without restriction, including
   9  * without limitation the rights to use, copy, modify, merge, publish,
  10  * distribute, sublicense, and/or sell copies of the Software, and to
  11  * permit persons to whom the Software is furnished to do so, subject to
  12  * the following conditions:
  13  *
  14  * The above copyright notice and this permission notice (including the
  15  * next paragraph) shall be included in all copies or substantial
  16  * portions of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  19  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  20  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
  21  * IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
  22  * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  23  * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  24  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  *
  26  */
  27
  28 /**
  29  * @file
  30  * Utilities to deal with the somewhat odd restriction on R300 fragment
  31  * program swizzles.
  32  */
  33
  34 #include "r300_fragprog_swizzle.h"
  35
  36 #include <stdio.h>
  37
  38 #include "r300_reg.h"
  39 #include "radeon_compiler.h"
  40
  41 #define MAKE_SWZ3(x, y, z) (RC_MAKE_SWIZZLE(RC_SWIZZLE_##x, RC_SWIZZLE_##y, RC_SWIZZLE_##z, RC_SWIZZLE_ZERO))
  42
  43 struct swizzle_data {
  44         unsigned int hash; /**< swizzle value this matches */
  45         unsigned int base; /**< base value for hw swizzle */
  46         unsigned int stride; /**< difference in base between arg0/1/2 */
  47         unsigned int srcp_stride; /**< difference in base between arg0/scrp */
  48 };
  49
  50 static const struct swizzle_data native_swizzles[] = {
  51         {MAKE_SWZ3(X, Y, Z), R300_ALU_ARGC_SRC0C_XYZ, 4, 15},
  52         {MAKE_SWZ3(X, X, X), R300_ALU_ARGC_SRC0C_XXX, 4, 15},
  53         {MAKE_SWZ3(Y, Y, Y), R300_ALU_ARGC_SRC0C_YYY, 4, 15},
  54         {MAKE_SWZ3(Z, Z, Z), R300_ALU_ARGC_SRC0C_ZZZ, 4, 15},
  55         {MAKE_SWZ3(W, W, W), R300_ALU_ARGC_SRC0A, 1, 7},
  56         {MAKE_SWZ3(Y, Z, X), R300_ALU_ARGC_SRC0C_YZX, 1, 0},
  57         {MAKE_SWZ3(Z, X, Y), R300_ALU_ARGC_SRC0C_ZXY, 1, 0},
  58         {MAKE_SWZ3(W, Z, Y), R300_ALU_ARGC_SRC0CA_WZY, 1, 0},
  59         {MAKE_SWZ3(ONE, ONE, ONE), R300_ALU_ARGC_ONE, 0, 0},
  60         {MAKE_SWZ3(ZERO, ZERO, ZERO), R300_ALU_ARGC_ZERO, 0, 0},
  61         {MAKE_SWZ3(HALF, HALF, HALF), R300_ALU_ARGC_HALF, 0, 0}
  62 };
  63
  64 static const int num_native_swizzles = sizeof(native_swizzles)/sizeof(native_swizzles[0]);
  65
  66 /**
  67  * Find a native RGB swizzle that matches the given swizzle.
  68  * Returns 0 if none found.
  69  */
  70 static const struct swizzle_data* lookup_native_swizzle(unsigned int swizzle)
  71 {
  72         int i, comp;
  73
  74         for(i = 0; i < num_native_swizzles; ++i) {
  75                 const struct swizzle_data* sd = &native_swizzles[i];
  76                 for(comp = 0; comp < 3; ++comp) {
  77                         unsigned int swz = GET_SWZ(swizzle, comp);
  78                         if (swz == RC_SWIZZLE_UNUSED)
  79                                 continue;
  80                         if (swz != GET_SWZ(sd->hash, comp))
  81                                 break;
  82                 }
  83                 if (comp == 3)
  84                         return sd;
  85         }
  86
  87         return 0;
  88 }
  89
  90 /**
  91  * Determines if the given swizzle is valid for r300/r400.  In most situations
  92  * it is better to use r300_swizzle_is_native() which can be accesed via
  93  * struct radeon_compiler *c; c->SwizzleCaps->IsNative().
  94  */
  95 int r300_swizzle_is_native_basic(unsigned int swizzle)
  96 {
  97         if(lookup_native_swizzle(swizzle))
  98                 return 1;
  99         else
 100                 return 0;
 101 }
 102
 103 /**
 104  * Check whether the given instruction supports the swizzle and negate
 105  * combinations in the given source register.
 106  */
 107 static int r300_swizzle_is_native(rc_opcode opcode, struct rc_src_register reg)
 108 {
 109         const struct swizzle_data* sd;
 110         unsigned int relevant;
 111         int j;
 112
 113         if (opcode == RC_OPCODE_KIL ||
 114             opcode == RC_OPCODE_TEX ||
 115             opcode == RC_OPCODE_TXB ||
 116             opcode == RC_OPCODE_TXP) {
 117                 if (reg.Abs || reg.Negate)
 118                         return 0;
 119
 120                 for(j = 0; j < 4; ++j) {
 121                         unsigned int swz = GET_SWZ(reg.Swizzle, j);
 122                         if (swz == RC_SWIZZLE_UNUSED)
 123                                 continue;
 124                         if (swz != j)
 125                                 return 0;
 126                 }
 127
 128                 return 1;
 129         }
 130
 131         relevant = 0;
 132
 133         for(j = 0; j < 3; ++j)
 134                 if (GET_SWZ(reg.Swizzle, j) != RC_SWIZZLE_UNUSED)
 135                         relevant |= 1 << j;
 136
 137         if ((reg.Negate & relevant) && ((reg.Negate & relevant) != relevant))
 138                 return 0;
 139
 140         sd = lookup_native_swizzle(reg.Swizzle);
 141         if (!sd || (reg.File == RC_FILE_PRESUB && sd->srcp_stride == 0))
 142                 return 0;
 143
 144         return 1;
 145 }
 146
 147
 148 static void r300_swizzle_split(
 149                 struct rc_src_register src, unsigned int mask,
 150                 struct rc_swizzle_split * split)
 151 {
 152         split->NumPhases = 0;
 153
 154         while(mask) {
 155                 unsigned int best_matchcount = 0;
 156                 unsigned int best_matchmask = 0;
 157                 int i, comp;
 158
 159                 for(i = 0; i < num_native_swizzles; ++i) {
 160                         const struct swizzle_data *sd = &native_swizzles[i];
 161                         unsigned int matchcount = 0;
 162                         unsigned int matchmask = 0;
 163                         for(comp = 0; comp < 3; ++comp) {
 164                                 unsigned int swz;
 165                                 if (!GET_BIT(mask, comp))
 166                                         continue;
 167                                 swz = GET_SWZ(src.Swizzle, comp);
 168                                 if (swz == RC_SWIZZLE_UNUSED)
 169                                         continue;
 170                                 if (swz == GET_SWZ(sd->hash, comp)) {
 171                                         /* check if the negate bit of current component
 172                                          * is the same for already matched components */
 173                                         if (matchmask && (!!(src.Negate & matchmask) != !!(src.Negate & (1 << comp))))
 174                                                 continue;
 175
 176                                         matchcount++;
 177                                         matchmask |= 1 << comp;
 178                                 }
 179                         }
 180                         if (matchcount > best_matchcount) {
 181                                 best_matchcount = matchcount;
 182                                 best_matchmask = matchmask;
 183                                 if (matchmask == (mask & RC_MASK_XYZ))
 184                                         break;
 185                         }
 186                 }
 187
 188                 if (mask & RC_MASK_W)
 189                         best_matchmask |= RC_MASK_W;
 190
 191                 split->Phase[split->NumPhases++] = best_matchmask;
 192                 mask &= ~best_matchmask;
 193         }
 194 }
 195
 196 struct rc_swizzle_caps r300_swizzle_caps = {
 197         .IsNative = r300_swizzle_is_native,
 198         .Split = r300_swizzle_split
 199 };
 200
 201
 202 /**
 203  * Translate an RGB (XYZ) swizzle into the hardware code for the given
 204  * instruction source.
 205  */
 206 unsigned int r300FPTranslateRGBSwizzle(unsigned int src, unsigned int swizzle)
 207 {
 208         const struct swizzle_data* sd = lookup_native_swizzle(swizzle);
 209
 210         if (!sd || (src == RC_PAIR_PRESUB_SRC && sd->srcp_stride == 0)) {
 211                 fprintf(stderr, "Not a native swizzle: %08x\n", swizzle);
 212                 return 0;
 213         }
 214
 215         if (src == RC_PAIR_PRESUB_SRC) {
 216                 return sd->base + sd->srcp_stride;
 217         } else {
 218                 return sd->base + src*sd->stride;
 219         }
 220 }
 221
 222
 223 /**
 224  * Translate an Alpha (W) swizzle into the hardware code for the given
 225  * instruction source.
 226  */
 227 unsigned int r300FPTranslateAlphaSwizzle(unsigned int src, unsigned int swizzle)
 228 {
 229         unsigned int swz = GET_SWZ(swizzle, 0);
 230         if (src == RC_PAIR_PRESUB_SRC) {
 231                 return R300_ALU_ARGA_SRCP_X + swz;
 232         }
 233         if (swz < 3)
 234                 return swz + 3*src;
 235
 236         switch(swz) {
 237         case RC_SWIZZLE_W: return R300_ALU_ARGA_SRC0A + src;
 238         case RC_SWIZZLE_ONE: return R300_ALU_ARGA_ONE;
 239         case RC_SWIZZLE_ZERO: return R300_ALU_ARGA_ZERO;
 240         case RC_SWIZZLE_HALF: return R300_ALU_ARGA_HALF;
 241         default: return R300_ALU_ARGA_ONE;
 242         }
 243 }