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
  35 #include "tgsi_transform.h"
  36
  37
  38
  39 static void
  40 emit_instruction(struct tgsi_transform_context *ctx,
  41                  const struct tgsi_full_instruction *inst)
  42 {
  43    uint ti = ctx->ti;
  44
  45    ti += tgsi_build_full_instruction(inst,
  46                                      ctx->tokens_out + ti,
  47                                      ctx->header,
  48                                      ctx->max_tokens_out - ti);
  49    ctx->ti = ti;
  50 }
  51
  52
  53 static void
  54 emit_declaration(struct tgsi_transform_context *ctx,
  55                  const struct tgsi_full_declaration *decl)
  56 {
  57    uint ti = ctx->ti;
  58
  59    ti += tgsi_build_full_declaration(decl,
  60                                      ctx->tokens_out + ti,
  61                                      ctx->header,
  62                                      ctx->max_tokens_out - ti);
  63    ctx->ti = ti;
  64 }
  65
  66
  67 static void
  68 emit_immediate(struct tgsi_transform_context *ctx,
  69                const struct tgsi_full_immediate *imm)
  70 {
  71    uint ti = ctx->ti;
  72
  73    ti += tgsi_build_full_immediate(imm,
  74                                    ctx->tokens_out + ti,
  75                                    ctx->header,
  76                                    ctx->max_tokens_out - ti);
  77    ctx->ti = ti;
  78 }
  79
  80
  81
  82 /**
  83  * Apply user-defined transformations to the input shader to produce
  84  * the output shader.
  85  * For example, a register search-and-replace operation could be applied
  86  * by defining a transform_instruction() callback that examined and changed
  87  * the instruction src/dest regs.
  88  *
  89  * \return number of tokens emitted
  90  */
  91 int
  92 tgsi_transform_shader(const struct tgsi_token *tokens_in,
  93                       struct tgsi_token *tokens_out,
  94                       uint max_tokens_out,
  95                       struct tgsi_transform_context *ctx)
  96 {
  97    uint procType;
  98
  99    /* input shader */
 100    struct tgsi_parse_context parse;
 101
 102    /* output shader */
 103    struct tgsi_processor *processor;
 104
 105
 106    /**
 107     ** callback context init
 108     **/
 109    ctx->emit_instruction = emit_instruction;
 110    ctx->emit_declaration = emit_declaration;
 111    ctx->emit_immediate = emit_immediate;
 112    ctx->tokens_out = tokens_out;
 113    ctx->max_tokens_out = max_tokens_out;
 114
 115
 116    /**
 117     ** Setup to begin parsing input shader
 118     **/
 119    if (tgsi_parse_init( &parse, tokens_in ) != TGSI_PARSE_OK) {
 120       debug_printf("tgsi_parse_init() failed in tgsi_transform_shader()!\n");
 121       return -1;
 122    }
 123    procType = parse.FullHeader.Processor.Processor;
 124    assert(procType == TGSI_PROCESSOR_FRAGMENT ||
 125           procType == TGSI_PROCESSOR_VERTEX ||
 126           procType == TGSI_PROCESSOR_GEOMETRY);
 127
 128
 129    /**
 130     **  Setup output shader
 131     **/
 132    *(struct tgsi_version *) &tokens_out[0] = tgsi_build_version();
 133
 134    ctx->header = (struct tgsi_header *) (tokens_out + 1);
 135    *ctx->header = tgsi_build_header();
 136
 137    processor = (struct tgsi_processor *) (tokens_out + 2);
 138    *processor = tgsi_build_processor( procType, ctx->header );
 139
 140    ctx->ti = 3;
 141
 142
 143    /**
 144     ** Loop over incoming program tokens/instructions
 145     */
 146    while( !tgsi_parse_end_of_tokens( &parse ) ) {
 147
 148       tgsi_parse_token( &parse );
 149
 150       switch( parse.FullToken.Token.Type ) {
 151       case TGSI_TOKEN_TYPE_INSTRUCTION:
 152          {
 153             struct tgsi_full_instruction *fullinst
 154                = &parse.FullToken.FullInstruction;
 155
 156             if (ctx->transform_instruction)
 157                ctx->transform_instruction(ctx, fullinst);
 158             else
 159                ctx->emit_instruction(ctx, fullinst);
 160          }
 161          break;
 162
 163       case TGSI_TOKEN_TYPE_DECLARATION:
 164          {
 165             struct tgsi_full_declaration *fulldecl
 166                = &parse.FullToken.FullDeclaration;
 167
 168             if (ctx->transform_declaration)
 169                ctx->transform_declaration(ctx, fulldecl);
 170             else
 171                ctx->emit_declaration(ctx, fulldecl);
 172          }
 173          break;
 174
 175       case TGSI_TOKEN_TYPE_IMMEDIATE:
 176          {
 177             struct tgsi_full_immediate *fullimm
 178                = &parse.FullToken.FullImmediate;
 179
 180             if (ctx->transform_immediate)
 181                ctx->transform_immediate(ctx, fullimm);
 182             else
 183                ctx->emit_immediate(ctx, fullimm);
 184          }
 185          break;
 186
 187       default:
 188          assert( 0 );
 189       }
 190    }
 191
 192    if (ctx->epilog) {
 193       ctx->epilog(ctx);
 194    }
 195
 196    tgsi_parse_free (&parse);
 197
 198    return ctx->ti;
 199 }