src/gallium/auxiliary/tgsi/tgsi_transform.c

   1 /**************************************************************************
   2  *
   3  * Copyright 2008 Tungsten Graphics, Inc., Cedar Park, Texas.
   4  * All Rights Reserved.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * 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, sub license, 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 portions
  16  * of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  19  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  20  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
  21  * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
  22  * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  23  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  24  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  *
  26  **************************************************************************/
  27
  28 /**
  29  * TGSI program transformation utility.
  30  *
  31  * Authors:  Brian Paul
  32  */
  33
  34 #include "util/u_debug.h"
  35
  36 #include "tgsi_transform.h"
  37
  38
  39
  40 static void
  41 emit_instruction(struct tgsi_transform_context *ctx,
  42                  const struct tgsi_full_instruction *inst)
  43 {
  44    uint ti = ctx->ti;
  45
  46    ti += tgsi_build_full_instruction(inst,
  47                                      ctx->tokens_out + ti,
  48                                      ctx->header,
  49                                      ctx->max_tokens_out - ti);
  50    ctx->ti = ti;
  51 }
  52
  53
  54 static void
  55 emit_declaration(struct tgsi_transform_context *ctx,
  56                  const struct tgsi_full_declaration *decl)
  57 {
  58    uint ti = ctx->ti;
  59
  60    ti += tgsi_build_full_declaration(decl,
  61                                      ctx->tokens_out + ti,
  62                                      ctx->header,
  63                                      ctx->max_tokens_out - ti);
  64    ctx->ti = ti;
  65 }
  66
  67
  68 static void
  69 emit_immediate(struct tgsi_transform_context *ctx,
  70                const struct tgsi_full_immediate *imm)
  71 {
  72    uint ti = ctx->ti;
  73
  74    ti += tgsi_build_full_immediate(imm,
  75                                    ctx->tokens_out + ti,
  76                                    ctx->header,
  77                                    ctx->max_tokens_out - ti);
  78    ctx->ti = ti;
  79 }
  80
  81
  82
  83 /**
  84  * Apply user-defined transformations to the input shader to produce
  85  * the output shader.
  86  * For example, a register search-and-replace operation could be applied
  87  * by defining a transform_instruction() callback that examined and changed
  88  * the instruction src/dest regs.
  89  *
  90  * \return number of tokens emitted
  91  */
  92 int
  93 tgsi_transform_shader(const struct tgsi_token *tokens_in,
  94                       struct tgsi_token *tokens_out,
  95                       uint max_tokens_out,
  96                       struct tgsi_transform_context *ctx)
  97 {
  98    uint procType;
  99
 100    /* input shader */
 101    struct tgsi_parse_context parse;
 102
 103    /* output shader */
 104    struct tgsi_processor *processor;
 105
 106
 107    /**
 108     ** callback context init
 109     **/
 110    ctx->emit_instruction = emit_instruction;
 111    ctx->emit_declaration = emit_declaration;
 112    ctx->emit_immediate = emit_immediate;
 113    ctx->tokens_out = tokens_out;
 114    ctx->max_tokens_out = max_tokens_out;
 115
 116
 117    /**
 118     ** Setup to begin parsing input shader
 119     **/
 120    if (tgsi_parse_init( &parse, tokens_in ) != TGSI_PARSE_OK) {
 121       debug_printf("tgsi_parse_init() failed in tgsi_transform_shader()!\n");
 122       return -1;
 123    }
 124    procType = parse.FullHeader.Processor.Processor;
 125    assert(procType == TGSI_PROCESSOR_FRAGMENT ||
 126           procType == TGSI_PROCESSOR_VERTEX ||
 127           procType == TGSI_PROCESSOR_GEOMETRY);
 128
 129
 130    /**
 131     **  Setup output shader
 132     **/
 133    ctx->header = (struct tgsi_header *)tokens_out;
 134    *ctx->header = tgsi_build_header();
 135
 136    processor = (struct tgsi_processor *) (tokens_out + 1);
 137    *processor = tgsi_build_processor( procType, ctx->header );
 138
 139    ctx->ti = 2;
 140
 141
 142    /**
 143     ** Loop over incoming program tokens/instructions
 144     */
 145    while( !tgsi_parse_end_of_tokens( &parse ) ) {
 146
 147       tgsi_parse_token( &parse );
 148
 149       switch( parse.FullToken.Token.Type ) {
 150       case TGSI_TOKEN_TYPE_INSTRUCTION:
 151          {
 152             struct tgsi_full_instruction *fullinst
 153                = &parse.FullToken.FullInstruction;
 154
 155             if (ctx->transform_instruction)
 156                ctx->transform_instruction(ctx, fullinst);
 157             else
 158                ctx->emit_instruction(ctx, fullinst);
 159          }
 160          break;
 161
 162       case TGSI_TOKEN_TYPE_DECLARATION:
 163          {
 164             struct tgsi_full_declaration *fulldecl
 165                = &parse.FullToken.FullDeclaration;
 166
 167             if (ctx->transform_declaration)
 168                ctx->transform_declaration(ctx, fulldecl);
 169             else
 170                ctx->emit_declaration(ctx, fulldecl);
 171          }
 172          break;
 173
 174       case TGSI_TOKEN_TYPE_IMMEDIATE:
 175          {
 176             struct tgsi_full_immediate *fullimm
 177                = &parse.FullToken.FullImmediate;
 178
 179             if (ctx->transform_immediate)
 180                ctx->transform_immediate(ctx, fullimm);
 181             else
 182                ctx->emit_immediate(ctx, fullimm);
 183          }
 184          break;
 185
 186       default:
 187          assert( 0 );
 188       }
 189    }
 190
 191    if (ctx->epilog) {
 192       ctx->epilog(ctx);
 193    }
 194
 195    tgsi_parse_free (&parse);
 196
 197    return ctx->ti;
 198 }
 199
 200
 201 #include "tgsi_text.h"
 202
 203 extern int tgsi_transform_foo( struct tgsi_token *tokens_out,
 204                                uint max_tokens_out );
 205
 206 /* This function exists only so that tgsi_text_translate() doesn't get
 207  * magic-ed out of the libtgsi.a archive by the build system.  Don't
 208  * remove unless you know this has been fixed - check on mingw/scons
 209  * builds as well.
 210  */
 211 int
 212 tgsi_transform_foo( struct tgsi_token *tokens_out,
 213                     uint max_tokens_out )
 214 {
 215    const char *text =
 216       "FRAG\n"
 217       "DCL IN[0], COLOR, CONSTANT\n"
 218       "DCL OUT[0], COLOR\n"
 219       "  0: MOV OUT[0], IN[0]\n"
 220       "  1: END";
 221
 222    return tgsi_text_translate( text,
 223                                tokens_out,
 224                                max_tokens_out );
 225 }