src/gallium/auxiliary/tgsi/tgsi_scan.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 scan utility.
  30  * Used to determine which registers and instructions are used by a shader.
  31  *
  32  * Authors:  Brian Paul
  33  */
  34
  35
  36 #include "util/u_math.h"
  37 #include "tgsi/tgsi_build.h"
  38 #include "tgsi/tgsi_parse.h"
  39 #include "tgsi/tgsi_scan.h"
  40
  41
  42
  43
  44 /**
  45  */
  46 void
  47 tgsi_scan_shader(const struct tgsi_token *tokens,
  48                  struct tgsi_shader_info *info)
  49 {
  50    uint procType, i;
  51    struct tgsi_parse_context parse;
  52
  53    memset(info, 0, sizeof(*info));
  54    for (i = 0; i < TGSI_FILE_COUNT; i++)
  55       info->file_max[i] = -1;
  56
  57    /**
  58     ** Setup to begin parsing input shader
  59     **/
  60    if (tgsi_parse_init( &parse, tokens ) != TGSI_PARSE_OK) {
  61       debug_printf("tgsi_parse_init() failed in tgsi_scan_shader()!\n");
  62       return;
  63    }
  64    procType = parse.FullHeader.Processor.Processor;
  65    assert(procType == TGSI_PROCESSOR_FRAGMENT ||
  66           procType == TGSI_PROCESSOR_VERTEX ||
  67           procType == TGSI_PROCESSOR_GEOMETRY);
  68
  69
  70    /**
  71     ** Loop over incoming program tokens/instructions
  72     */
  73    while( !tgsi_parse_end_of_tokens( &parse ) ) {
  74
  75       info->num_tokens++;
  76
  77       tgsi_parse_token( &parse );
  78
  79       switch( parse.FullToken.Token.Type ) {
  80       case TGSI_TOKEN_TYPE_INSTRUCTION:
  81          {
  82             struct tgsi_full_instruction *fullinst
  83                = &parse.FullToken.FullInstruction;
  84
  85             assert(fullinst->Instruction.Opcode < TGSI_OPCODE_LAST);
  86             info->opcode_count[fullinst->Instruction.Opcode]++;
  87          }
  88          break;
  89
  90       case TGSI_TOKEN_TYPE_DECLARATION:
  91          {
  92             struct tgsi_full_declaration *fulldecl
  93                = &parse.FullToken.FullDeclaration;
  94             uint file = fulldecl->Declaration.File;
  95             uint i;
  96             for (i = fulldecl->DeclarationRange.First;
  97                  i <= fulldecl->DeclarationRange.Last;
  98                  i++) {
  99
 100                /* only first 32 regs will appear in this bitfield */
 101                info->file_mask[file] |= (1 << i);
 102                info->file_count[file]++;
 103                info->file_max[file] = MAX2(info->file_max[file], (int)i);
 104
 105                if (file == TGSI_FILE_INPUT) {
 106                   info->input_semantic_name[i] = (ubyte)fulldecl->Semantic.SemanticName;
 107                   info->input_semantic_index[i] = (ubyte)fulldecl->Semantic.SemanticIndex;
 108                   info->num_inputs++;
 109                }
 110
 111                if (file == TGSI_FILE_OUTPUT) {
 112                   info->output_semantic_name[i] = (ubyte)fulldecl->Semantic.SemanticName;
 113                   info->output_semantic_index[i] = (ubyte)fulldecl->Semantic.SemanticIndex;
 114                   info->num_outputs++;
 115                }
 116
 117                /* special case */
 118                if (procType == TGSI_PROCESSOR_FRAGMENT &&
 119                    file == TGSI_FILE_OUTPUT &&
 120                    fulldecl->Semantic.SemanticName == TGSI_SEMANTIC_POSITION) {
 121                   info->writes_z = TRUE;
 122                }
 123             }
 124          }
 125          break;
 126
 127       case TGSI_TOKEN_TYPE_IMMEDIATE:
 128          info->immediate_count++;
 129          break;
 130
 131       default:
 132          assert( 0 );
 133       }
 134    }
 135
 136    assert( info->file_max[TGSI_FILE_INPUT] + 1 == info->num_inputs );
 137    assert( info->file_max[TGSI_FILE_OUTPUT] + 1 == info->num_outputs );
 138
 139    info->uses_kill = (info->opcode_count[TGSI_OPCODE_KIL] ||
 140                       info->opcode_count[TGSI_OPCODE_KILP]);
 141
 142    tgsi_parse_free (&parse);
 143 }
 144
 145
 146
 147 /**
 148  * Check if the given shader is a "passthrough" shader consisting of only
 149  * MOV instructions of the form:  MOV OUT[n], IN[n]
 150  *
 151  */
 152 boolean
 153 tgsi_is_passthrough_shader(const struct tgsi_token *tokens)
 154 {
 155    struct tgsi_parse_context parse;
 156
 157    /**
 158     ** Setup to begin parsing input shader
 159     **/
 160    if (tgsi_parse_init(&parse, tokens) != TGSI_PARSE_OK) {
 161       debug_printf("tgsi_parse_init() failed in tgsi_is_passthrough_shader()!\n");
 162       return FALSE;
 163    }
 164
 165    /**
 166     ** Loop over incoming program tokens/instructions
 167     */
 168    while (!tgsi_parse_end_of_tokens(&parse)) {
 169
 170       tgsi_parse_token(&parse);
 171
 172       switch (parse.FullToken.Token.Type) {
 173       case TGSI_TOKEN_TYPE_INSTRUCTION:
 174          {
 175             struct tgsi_full_instruction *fullinst =
 176                &parse.FullToken.FullInstruction;
 177             const struct tgsi_full_src_register *src =
 178                &fullinst->FullSrcRegisters[0];
 179             const struct tgsi_full_dst_register *dst =
 180                &fullinst->FullDstRegisters[0];
 181
 182             /* Do a whole bunch of checks for a simple move */
 183             if (fullinst->Instruction.Opcode != TGSI_OPCODE_MOV ||
 184                 src->SrcRegister.File != TGSI_FILE_INPUT ||
 185                 dst->DstRegister.File != TGSI_FILE_OUTPUT ||
 186                 src->SrcRegister.Index != dst->DstRegister.Index ||
 187
 188                 src->SrcRegister.Negate ||
 189                 src->SrcRegisterExtMod.Negate ||
 190                 src->SrcRegisterExtMod.Absolute ||
 191                 src->SrcRegisterExtMod.Scale2X ||
 192                 src->SrcRegisterExtMod.Bias ||
 193                 src->SrcRegisterExtMod.Complement ||
 194
 195                 src->SrcRegister.SwizzleX != TGSI_SWIZZLE_X ||
 196                 src->SrcRegister.SwizzleY != TGSI_SWIZZLE_Y ||
 197                 src->SrcRegister.SwizzleZ != TGSI_SWIZZLE_Z ||
 198                 src->SrcRegister.SwizzleW != TGSI_SWIZZLE_W ||
 199
 200                 src->SrcRegisterExtSwz.ExtSwizzleX != TGSI_EXTSWIZZLE_X ||
 201                 src->SrcRegisterExtSwz.ExtSwizzleY != TGSI_EXTSWIZZLE_Y ||
 202                 src->SrcRegisterExtSwz.ExtSwizzleZ != TGSI_EXTSWIZZLE_Z ||
 203                 src->SrcRegisterExtSwz.ExtSwizzleW != TGSI_EXTSWIZZLE_W ||
 204
 205                 dst->DstRegister.WriteMask != TGSI_WRITEMASK_XYZW)
 206             {
 207                tgsi_parse_free(&parse);
 208                return FALSE;
 209             }
 210          }
 211          break;
 212
 213       case TGSI_TOKEN_TYPE_DECLARATION:
 214          /* fall-through */
 215       case TGSI_TOKEN_TYPE_IMMEDIATE:
 216          /* fall-through */
 217       default:
 218          ; /* no-op */
 219       }
 220    }
 221
 222    tgsi_parse_free(&parse);
 223
 224    /* if we get here, it's a pass-through shader */
 225    return TRUE;
 226 }