tgsi_scan.c revision cdc920a0 
1/**************************************************************************
2 *
3 * Copyright 2008 Tungsten Graphics, Inc., Cedar Park, Texas.
4 * All Rights Reserved.
5 * Copyright 2008 VMware, Inc.  All rights Reserved.
6 *
7 * Permission is hereby granted, free of charge, to any person obtaining a
8 * copy of this software and associated documentation files (the
9 * "Software"), to deal in the Software without restriction, including
10 * without limitation the rights to use, copy, modify, merge, publish,
11 * distribute, sub license, and/or sell copies of the Software, and to
12 * permit persons to whom the Software is furnished to do so, subject to
13 * the following conditions:
14 *
15 * The above copyright notice and this permission notice (including the
16 * next paragraph) shall be included in all copies or substantial portions
17 * of the Software.
18 *
19 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
20 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
21 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
22 * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
23 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
24 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
25 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
26 *
27 **************************************************************************/
28
29/**
30 * TGSI program scan utility.
31 * Used to determine which registers and instructions are used by a shader.
32 *
33 * Authors:  Brian Paul
34 */
35
36
37#include "util/u_math.h"
38#include "tgsi/tgsi_parse.h"
39#include "tgsi/tgsi_scan.h"
40
41
42
43
44/**
45 * Scan the given TGSI shader to collect information such as number of
46 * registers used, special instructions used, etc.
47 * \return info  the result of the scan
48 */
49void
50tgsi_scan_shader(const struct tgsi_token *tokens,
51                 struct tgsi_shader_info *info)
52{
53   uint procType, i;
54   struct tgsi_parse_context parse;
55
56   memset(info, 0, sizeof(*info));
57   for (i = 0; i < TGSI_FILE_COUNT; i++)
58      info->file_max[i] = -1;
59
60   /**
61    ** Setup to begin parsing input shader
62    **/
63   if (tgsi_parse_init( &parse, tokens ) != TGSI_PARSE_OK) {
64      debug_printf("tgsi_parse_init() failed in tgsi_scan_shader()!\n");
65      return;
66   }
67   procType = parse.FullHeader.Processor.Processor;
68   assert(procType == TGSI_PROCESSOR_FRAGMENT ||
69          procType == TGSI_PROCESSOR_VERTEX ||
70          procType == TGSI_PROCESSOR_GEOMETRY);
71
72
73   /**
74    ** Loop over incoming program tokens/instructions
75    */
76   while( !tgsi_parse_end_of_tokens( &parse ) ) {
77
78      info->num_tokens++;
79
80      tgsi_parse_token( &parse );
81
82      switch( parse.FullToken.Token.Type ) {
83      case TGSI_TOKEN_TYPE_INSTRUCTION:
84         {
85            const struct tgsi_full_instruction *fullinst
86               = &parse.FullToken.FullInstruction;
87
88            assert(fullinst->Instruction.Opcode < TGSI_OPCODE_LAST);
89            info->opcode_count[fullinst->Instruction.Opcode]++;
90
91            /* special case: scan fragment shaders for use of the fog
92             * input/attribute.  The X component is fog, the Y component
93             * is the front/back-face flag.
94             */
95            if (procType == TGSI_PROCESSOR_FRAGMENT) {
96               uint i;
97               for (i = 0; i < fullinst->Instruction.NumSrcRegs; i++) {
98                  const struct tgsi_full_src_register *src =
99                     &fullinst->Src[i];
100                  if (src->Register.File == TGSI_FILE_INPUT ||
101                      src->Register.File == TGSI_FILE_SYSTEM_VALUE) {
102                     const int ind = src->Register.Index;
103                     if (info->input_semantic_name[ind] == TGSI_SEMANTIC_FOG) {
104                        info->uses_fogcoord = TRUE;
105                     }
106                     else if (info->input_semantic_name[ind] == TGSI_SEMANTIC_FACE) {
107                        info->uses_frontfacing = TRUE;
108                     }
109                  }
110               }
111            }
112         }
113         break;
114
115      case TGSI_TOKEN_TYPE_DECLARATION:
116         {
117            const struct tgsi_full_declaration *fulldecl
118               = &parse.FullToken.FullDeclaration;
119            const uint file = fulldecl->Declaration.File;
120            uint reg;
121            for (reg = fulldecl->Range.First;
122                 reg <= fulldecl->Range.Last;
123                 reg++) {
124
125               /* only first 32 regs will appear in this bitfield */
126               info->file_mask[file] |= (1 << reg);
127               info->file_count[file]++;
128               info->file_max[file] = MAX2(info->file_max[file], (int)reg);
129
130               if (file == TGSI_FILE_INPUT || file == TGSI_FILE_SYSTEM_VALUE) {
131                  info->input_semantic_name[reg] = (ubyte)fulldecl->Semantic.Name;
132                  info->input_semantic_index[reg] = (ubyte)fulldecl->Semantic.Index;
133                  info->input_interpolate[reg] = (ubyte)fulldecl->Declaration.Interpolate;
134                  info->input_cylindrical_wrap[reg] = (ubyte)fulldecl->Declaration.CylindricalWrap;
135                  info->num_inputs++;
136               }
137               else if (file == TGSI_FILE_OUTPUT) {
138                  info->output_semantic_name[reg] = (ubyte)fulldecl->Semantic.Name;
139                  info->output_semantic_index[reg] = (ubyte)fulldecl->Semantic.Index;
140                  info->num_outputs++;
141
142                  /* extra info for special outputs */
143                  if (procType == TGSI_PROCESSOR_FRAGMENT &&
144                      fulldecl->Semantic.Name == TGSI_SEMANTIC_POSITION) {
145                     info->writes_z = TRUE;
146                  }
147                  if (procType == TGSI_PROCESSOR_VERTEX &&
148                      fulldecl->Semantic.Name == TGSI_SEMANTIC_EDGEFLAG) {
149                     info->writes_edgeflag = TRUE;
150                  }
151               }
152
153             }
154         }
155         break;
156
157      case TGSI_TOKEN_TYPE_IMMEDIATE:
158         {
159            uint reg = info->immediate_count++;
160            uint file = TGSI_FILE_IMMEDIATE;
161
162            info->file_mask[file] |= (1 << reg);
163            info->file_count[file]++;
164            info->file_max[file] = MAX2(info->file_max[file], (int)reg);
165         }
166         break;
167      case TGSI_TOKEN_TYPE_PROPERTY:
168      {
169         const struct tgsi_full_property *fullprop
170            = &parse.FullToken.FullProperty;
171
172         info->properties[info->num_properties].name =
173            fullprop->Property.PropertyName;
174         memcpy(info->properties[info->num_properties].data,
175                fullprop->u, 8 * sizeof(unsigned));;
176
177         ++info->num_properties;
178      }
179      break;
180
181      default:
182         assert( 0 );
183      }
184   }
185
186   info->uses_kill = (info->opcode_count[TGSI_OPCODE_KIL] ||
187                      info->opcode_count[TGSI_OPCODE_KILP]);
188
189   tgsi_parse_free (&parse);
190}
191
192
193
194/**
195 * Check if the given shader is a "passthrough" shader consisting of only
196 * MOV instructions of the form:  MOV OUT[n], IN[n]
197 *
198 */
199boolean
200tgsi_is_passthrough_shader(const struct tgsi_token *tokens)
201{
202   struct tgsi_parse_context parse;
203
204   /**
205    ** Setup to begin parsing input shader
206    **/
207   if (tgsi_parse_init(&parse, tokens) != TGSI_PARSE_OK) {
208      debug_printf("tgsi_parse_init() failed in tgsi_is_passthrough_shader()!\n");
209      return FALSE;
210   }
211
212   /**
213    ** Loop over incoming program tokens/instructions
214    */
215   while (!tgsi_parse_end_of_tokens(&parse)) {
216
217      tgsi_parse_token(&parse);
218
219      switch (parse.FullToken.Token.Type) {
220      case TGSI_TOKEN_TYPE_INSTRUCTION:
221         {
222            struct tgsi_full_instruction *fullinst =
223               &parse.FullToken.FullInstruction;
224            const struct tgsi_full_src_register *src =
225               &fullinst->Src[0];
226            const struct tgsi_full_dst_register *dst =
227               &fullinst->Dst[0];
228
229            /* Do a whole bunch of checks for a simple move */
230            if (fullinst->Instruction.Opcode != TGSI_OPCODE_MOV ||
231                (src->Register.File != TGSI_FILE_INPUT &&
232                 src->Register.File != TGSI_FILE_SYSTEM_VALUE) ||
233                dst->Register.File != TGSI_FILE_OUTPUT ||
234                src->Register.Index != dst->Register.Index ||
235
236                src->Register.Negate ||
237                src->Register.Absolute ||
238
239                src->Register.SwizzleX != TGSI_SWIZZLE_X ||
240                src->Register.SwizzleY != TGSI_SWIZZLE_Y ||
241                src->Register.SwizzleZ != TGSI_SWIZZLE_Z ||
242                src->Register.SwizzleW != TGSI_SWIZZLE_W ||
243
244                dst->Register.WriteMask != TGSI_WRITEMASK_XYZW)
245            {
246               tgsi_parse_free(&parse);
247               return FALSE;
248            }
249         }
250         break;
251
252      case TGSI_TOKEN_TYPE_DECLARATION:
253         /* fall-through */
254      case TGSI_TOKEN_TYPE_IMMEDIATE:
255         /* fall-through */
256      case TGSI_TOKEN_TYPE_PROPERTY:
257         /* fall-through */
258      default:
259         ; /* no-op */
260      }
261   }
262
263   tgsi_parse_free(&parse);
264
265   /* if we get here, it's a pass-through shader */
266   return TRUE;
267}
268