2 * Mesa 3-D graphics library
4 * Copyright (C) 1999-2007 Brian Paul All Rights Reserved.
6 * Permission is hereby granted, free of charge, to any person obtaining a
7 * copy of this software and associated documentation files (the "Software"),
8 * to deal in the Software without restriction, including without limitation
9 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
10 * and/or sell copies of the Software, and to permit persons to whom the
11 * Software is furnished to do so, subject to the following conditions:
13 * The above copyright notice and this permission notice shall be included
14 * in all copies or substantial portions of the Software.
16 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
17 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
18 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
19 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR
20 * OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
21 * ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR
22 * OTHER DEALINGS IN THE SOFTWARE.
27 * Vertex/Fragment program optimizations and transformations for program
34 #include "main/glheader.h"
35 #include "main/context.h"
36 #include "prog_parameter.h"
37 #include "prog_statevars.h"
39 #include "programopt.h"
40 #include "prog_instruction.h"
44 * This function inserts instructions for coordinate modelview * projection
45 * into a vertex program.
46 * May be used to implement the position_invariant option.
49 _mesa_insert_mvp_dp4_code(struct gl_context
*ctx
, struct gl_vertex_program
*vprog
)
51 struct prog_instruction
*newInst
;
52 const GLuint origLen
= vprog
->Base
.NumInstructions
;
53 const GLuint newLen
= origLen
+ 4;
57 * Setup state references for the modelview/projection matrix.
58 * XXX we should check if these state vars are already declared.
60 static const gl_state_index mvpState
[4][STATE_LENGTH
] = {
61 { STATE_MVP_MATRIX
, 0, 0, 0, 0 }, /* state.matrix.mvp.row[0] */
62 { STATE_MVP_MATRIX
, 0, 1, 1, 0 }, /* state.matrix.mvp.row[1] */
63 { STATE_MVP_MATRIX
, 0, 2, 2, 0 }, /* state.matrix.mvp.row[2] */
64 { STATE_MVP_MATRIX
, 0, 3, 3, 0 }, /* state.matrix.mvp.row[3] */
68 for (i
= 0; i
< 4; i
++) {
69 mvpRef
[i
] = _mesa_add_state_reference(vprog
->Base
.Parameters
,
73 /* Alloc storage for new instructions */
74 newInst
= _mesa_alloc_instructions(newLen
);
76 _mesa_error(ctx
, GL_OUT_OF_MEMORY
,
77 "glProgramString(inserting position_invariant code)");
82 * Generated instructions:
83 * newInst[0] = DP4 result.position.x, mvp.row[0], vertex.position;
84 * newInst[1] = DP4 result.position.y, mvp.row[1], vertex.position;
85 * newInst[2] = DP4 result.position.z, mvp.row[2], vertex.position;
86 * newInst[3] = DP4 result.position.w, mvp.row[3], vertex.position;
88 _mesa_init_instructions(newInst
, 4);
89 for (i
= 0; i
< 4; i
++) {
90 newInst
[i
].Opcode
= OPCODE_DP4
;
91 newInst
[i
].DstReg
.File
= PROGRAM_OUTPUT
;
92 newInst
[i
].DstReg
.Index
= VARYING_SLOT_POS
;
93 newInst
[i
].DstReg
.WriteMask
= (WRITEMASK_X
<< i
);
94 newInst
[i
].SrcReg
[0].File
= PROGRAM_STATE_VAR
;
95 newInst
[i
].SrcReg
[0].Index
= mvpRef
[i
];
96 newInst
[i
].SrcReg
[0].Swizzle
= SWIZZLE_NOOP
;
97 newInst
[i
].SrcReg
[1].File
= PROGRAM_INPUT
;
98 newInst
[i
].SrcReg
[1].Index
= VERT_ATTRIB_POS
;
99 newInst
[i
].SrcReg
[1].Swizzle
= SWIZZLE_NOOP
;
102 /* Append original instructions after new instructions */
103 _mesa_copy_instructions (newInst
+ 4, vprog
->Base
.Instructions
, origLen
);
105 /* free old instructions */
106 _mesa_free_instructions(vprog
->Base
.Instructions
, origLen
);
108 /* install new instructions */
109 vprog
->Base
.Instructions
= newInst
;
110 vprog
->Base
.NumInstructions
= newLen
;
111 vprog
->Base
.InputsRead
|= VERT_BIT_POS
;
112 vprog
->Base
.OutputsWritten
|= BITFIELD64_BIT(VARYING_SLOT_POS
);
117 _mesa_insert_mvp_mad_code(struct gl_context
*ctx
, struct gl_vertex_program
*vprog
)
119 struct prog_instruction
*newInst
;
120 const GLuint origLen
= vprog
->Base
.NumInstructions
;
121 const GLuint newLen
= origLen
+ 4;
126 * Setup state references for the modelview/projection matrix.
127 * XXX we should check if these state vars are already declared.
129 static const gl_state_index mvpState
[4][STATE_LENGTH
] = {
130 { STATE_MVP_MATRIX
, 0, 0, 0, STATE_MATRIX_TRANSPOSE
},
131 { STATE_MVP_MATRIX
, 0, 1, 1, STATE_MATRIX_TRANSPOSE
},
132 { STATE_MVP_MATRIX
, 0, 2, 2, STATE_MATRIX_TRANSPOSE
},
133 { STATE_MVP_MATRIX
, 0, 3, 3, STATE_MATRIX_TRANSPOSE
},
137 for (i
= 0; i
< 4; i
++) {
138 mvpRef
[i
] = _mesa_add_state_reference(vprog
->Base
.Parameters
,
142 /* Alloc storage for new instructions */
143 newInst
= _mesa_alloc_instructions(newLen
);
145 _mesa_error(ctx
, GL_OUT_OF_MEMORY
,
146 "glProgramString(inserting position_invariant code)");
151 hposTemp
= vprog
->Base
.NumTemporaries
++;
154 * Generated instructions:
155 * emit_op2(p, OPCODE_MUL, tmp, 0, swizzle1(src,X), mat[0]);
156 * emit_op3(p, OPCODE_MAD, tmp, 0, swizzle1(src,Y), mat[1], tmp);
157 * emit_op3(p, OPCODE_MAD, tmp, 0, swizzle1(src,Z), mat[2], tmp);
158 * emit_op3(p, OPCODE_MAD, dest, 0, swizzle1(src,W), mat[3], tmp);
160 _mesa_init_instructions(newInst
, 4);
162 newInst
[0].Opcode
= OPCODE_MUL
;
163 newInst
[0].DstReg
.File
= PROGRAM_TEMPORARY
;
164 newInst
[0].DstReg
.Index
= hposTemp
;
165 newInst
[0].DstReg
.WriteMask
= WRITEMASK_XYZW
;
166 newInst
[0].SrcReg
[0].File
= PROGRAM_INPUT
;
167 newInst
[0].SrcReg
[0].Index
= VERT_ATTRIB_POS
;
168 newInst
[0].SrcReg
[0].Swizzle
= SWIZZLE_XXXX
;
169 newInst
[0].SrcReg
[1].File
= PROGRAM_STATE_VAR
;
170 newInst
[0].SrcReg
[1].Index
= mvpRef
[0];
171 newInst
[0].SrcReg
[1].Swizzle
= SWIZZLE_NOOP
;
173 for (i
= 1; i
<= 2; i
++) {
174 newInst
[i
].Opcode
= OPCODE_MAD
;
175 newInst
[i
].DstReg
.File
= PROGRAM_TEMPORARY
;
176 newInst
[i
].DstReg
.Index
= hposTemp
;
177 newInst
[i
].DstReg
.WriteMask
= WRITEMASK_XYZW
;
178 newInst
[i
].SrcReg
[0].File
= PROGRAM_INPUT
;
179 newInst
[i
].SrcReg
[0].Index
= VERT_ATTRIB_POS
;
180 newInst
[i
].SrcReg
[0].Swizzle
= MAKE_SWIZZLE4(i
,i
,i
,i
);
181 newInst
[i
].SrcReg
[1].File
= PROGRAM_STATE_VAR
;
182 newInst
[i
].SrcReg
[1].Index
= mvpRef
[i
];
183 newInst
[i
].SrcReg
[1].Swizzle
= SWIZZLE_NOOP
;
184 newInst
[i
].SrcReg
[2].File
= PROGRAM_TEMPORARY
;
185 newInst
[i
].SrcReg
[2].Index
= hposTemp
;
186 newInst
[1].SrcReg
[2].Swizzle
= SWIZZLE_NOOP
;
189 newInst
[3].Opcode
= OPCODE_MAD
;
190 newInst
[3].DstReg
.File
= PROGRAM_OUTPUT
;
191 newInst
[3].DstReg
.Index
= VARYING_SLOT_POS
;
192 newInst
[3].DstReg
.WriteMask
= WRITEMASK_XYZW
;
193 newInst
[3].SrcReg
[0].File
= PROGRAM_INPUT
;
194 newInst
[3].SrcReg
[0].Index
= VERT_ATTRIB_POS
;
195 newInst
[3].SrcReg
[0].Swizzle
= SWIZZLE_WWWW
;
196 newInst
[3].SrcReg
[1].File
= PROGRAM_STATE_VAR
;
197 newInst
[3].SrcReg
[1].Index
= mvpRef
[3];
198 newInst
[3].SrcReg
[1].Swizzle
= SWIZZLE_NOOP
;
199 newInst
[3].SrcReg
[2].File
= PROGRAM_TEMPORARY
;
200 newInst
[3].SrcReg
[2].Index
= hposTemp
;
201 newInst
[3].SrcReg
[2].Swizzle
= SWIZZLE_NOOP
;
204 /* Append original instructions after new instructions */
205 _mesa_copy_instructions (newInst
+ 4, vprog
->Base
.Instructions
, origLen
);
207 /* free old instructions */
208 _mesa_free_instructions(vprog
->Base
.Instructions
, origLen
);
210 /* install new instructions */
211 vprog
->Base
.Instructions
= newInst
;
212 vprog
->Base
.NumInstructions
= newLen
;
213 vprog
->Base
.InputsRead
|= VERT_BIT_POS
;
214 vprog
->Base
.OutputsWritten
|= BITFIELD64_BIT(VARYING_SLOT_POS
);
219 _mesa_insert_mvp_code(struct gl_context
*ctx
, struct gl_vertex_program
*vprog
)
221 if (ctx
->Const
.ShaderCompilerOptions
[MESA_SHADER_VERTEX
].OptimizeForAOS
)
222 _mesa_insert_mvp_dp4_code( ctx
, vprog
);
224 _mesa_insert_mvp_mad_code( ctx
, vprog
);
233 * Append instructions to implement fog
235 * The \c fragment.fogcoord input is used to compute the fog blend factor.
237 * \param ctx The GL context
238 * \param fprog Fragment program that fog instructions will be appended to.
239 * \param fog_mode Fog mode. One of \c GL_EXP, \c GL_EXP2, or \c GL_LINEAR.
240 * \param saturate True if writes to color outputs should be clamped to [0, 1]
243 * This function sets \c VARYING_BIT_FOGC in \c fprog->Base.InputsRead.
245 * \todo With a little work, this function could be adapted to add fog code
246 * to vertex programs too.
249 _mesa_append_fog_code(struct gl_context
*ctx
,
250 struct gl_fragment_program
*fprog
, GLenum fog_mode
,
253 static const gl_state_index fogPStateOpt
[STATE_LENGTH
]
254 = { STATE_INTERNAL
, STATE_FOG_PARAMS_OPTIMIZED
, 0, 0, 0 };
255 static const gl_state_index fogColorState
[STATE_LENGTH
]
256 = { STATE_FOG_COLOR
, 0, 0, 0, 0};
257 struct prog_instruction
*newInst
, *inst
;
258 const GLuint origLen
= fprog
->Base
.NumInstructions
;
259 const GLuint newLen
= origLen
+ 5;
261 GLint fogPRefOpt
, fogColorRef
; /* state references */
262 GLuint colorTemp
, fogFactorTemp
; /* temporary registerss */
264 if (fog_mode
== GL_NONE
) {
265 _mesa_problem(ctx
, "_mesa_append_fog_code() called for fragment program"
266 " with fog_mode == GL_NONE");
270 if (!(fprog
->Base
.OutputsWritten
& (1 << FRAG_RESULT_COLOR
))) {
271 /* program doesn't output color, so nothing to do */
275 /* Alloc storage for new instructions */
276 newInst
= _mesa_alloc_instructions(newLen
);
278 _mesa_error(ctx
, GL_OUT_OF_MEMORY
,
279 "glProgramString(inserting fog_option code)");
283 /* Copy orig instructions into new instruction buffer */
284 _mesa_copy_instructions(newInst
, fprog
->Base
.Instructions
, origLen
);
286 /* PARAM fogParamsRefOpt = internal optimized fog params; */
288 = _mesa_add_state_reference(fprog
->Base
.Parameters
, fogPStateOpt
);
289 /* PARAM fogColorRef = state.fog.color; */
291 = _mesa_add_state_reference(fprog
->Base
.Parameters
, fogColorState
);
293 /* TEMP colorTemp; */
294 colorTemp
= fprog
->Base
.NumTemporaries
++;
295 /* TEMP fogFactorTemp; */
296 fogFactorTemp
= fprog
->Base
.NumTemporaries
++;
298 /* Scan program to find where result.color is written */
300 for (i
= 0; i
< fprog
->Base
.NumInstructions
; i
++) {
301 if (inst
->Opcode
== OPCODE_END
)
303 if (inst
->DstReg
.File
== PROGRAM_OUTPUT
&&
304 inst
->DstReg
.Index
== FRAG_RESULT_COLOR
) {
305 /* change the instruction to write to colorTemp w/ clamping */
306 inst
->DstReg
.File
= PROGRAM_TEMPORARY
;
307 inst
->DstReg
.Index
= colorTemp
;
308 inst
->SaturateMode
= saturate
;
309 /* don't break (may be several writes to result.color) */
313 assert(inst
->Opcode
== OPCODE_END
); /* we'll overwrite this inst */
315 _mesa_init_instructions(inst
, 5);
317 /* emit instructions to compute fog blending factor */
318 /* this is always clamped to [0, 1] regardless of fragment clamping */
319 if (fog_mode
== GL_LINEAR
) {
320 /* MAD fogFactorTemp.x, fragment.fogcoord.x, fogPRefOpt.x, fogPRefOpt.y; */
321 inst
->Opcode
= OPCODE_MAD
;
322 inst
->DstReg
.File
= PROGRAM_TEMPORARY
;
323 inst
->DstReg
.Index
= fogFactorTemp
;
324 inst
->DstReg
.WriteMask
= WRITEMASK_X
;
325 inst
->SrcReg
[0].File
= PROGRAM_INPUT
;
326 inst
->SrcReg
[0].Index
= VARYING_SLOT_FOGC
;
327 inst
->SrcReg
[0].Swizzle
= SWIZZLE_XXXX
;
328 inst
->SrcReg
[1].File
= PROGRAM_STATE_VAR
;
329 inst
->SrcReg
[1].Index
= fogPRefOpt
;
330 inst
->SrcReg
[1].Swizzle
= SWIZZLE_XXXX
;
331 inst
->SrcReg
[2].File
= PROGRAM_STATE_VAR
;
332 inst
->SrcReg
[2].Index
= fogPRefOpt
;
333 inst
->SrcReg
[2].Swizzle
= SWIZZLE_YYYY
;
334 inst
->SaturateMode
= SATURATE_ZERO_ONE
;
338 assert(fog_mode
== GL_EXP
|| fog_mode
== GL_EXP2
);
339 /* fogPRefOpt.z = d/ln(2), fogPRefOpt.w = d/sqrt(ln(2) */
340 /* EXP: MUL fogFactorTemp.x, fogPRefOpt.z, fragment.fogcoord.x; */
341 /* EXP2: MUL fogFactorTemp.x, fogPRefOpt.w, fragment.fogcoord.x; */
342 inst
->Opcode
= OPCODE_MUL
;
343 inst
->DstReg
.File
= PROGRAM_TEMPORARY
;
344 inst
->DstReg
.Index
= fogFactorTemp
;
345 inst
->DstReg
.WriteMask
= WRITEMASK_X
;
346 inst
->SrcReg
[0].File
= PROGRAM_STATE_VAR
;
347 inst
->SrcReg
[0].Index
= fogPRefOpt
;
348 inst
->SrcReg
[0].Swizzle
349 = (fog_mode
== GL_EXP
) ? SWIZZLE_ZZZZ
: SWIZZLE_WWWW
;
350 inst
->SrcReg
[1].File
= PROGRAM_INPUT
;
351 inst
->SrcReg
[1].Index
= VARYING_SLOT_FOGC
;
352 inst
->SrcReg
[1].Swizzle
= SWIZZLE_XXXX
;
354 if (fog_mode
== GL_EXP2
) {
355 /* MUL fogFactorTemp.x, fogFactorTemp.x, fogFactorTemp.x; */
356 inst
->Opcode
= OPCODE_MUL
;
357 inst
->DstReg
.File
= PROGRAM_TEMPORARY
;
358 inst
->DstReg
.Index
= fogFactorTemp
;
359 inst
->DstReg
.WriteMask
= WRITEMASK_X
;
360 inst
->SrcReg
[0].File
= PROGRAM_TEMPORARY
;
361 inst
->SrcReg
[0].Index
= fogFactorTemp
;
362 inst
->SrcReg
[0].Swizzle
= SWIZZLE_XXXX
;
363 inst
->SrcReg
[1].File
= PROGRAM_TEMPORARY
;
364 inst
->SrcReg
[1].Index
= fogFactorTemp
;
365 inst
->SrcReg
[1].Swizzle
= SWIZZLE_XXXX
;
368 /* EX2_SAT fogFactorTemp.x, -fogFactorTemp.x; */
369 inst
->Opcode
= OPCODE_EX2
;
370 inst
->DstReg
.File
= PROGRAM_TEMPORARY
;
371 inst
->DstReg
.Index
= fogFactorTemp
;
372 inst
->DstReg
.WriteMask
= WRITEMASK_X
;
373 inst
->SrcReg
[0].File
= PROGRAM_TEMPORARY
;
374 inst
->SrcReg
[0].Index
= fogFactorTemp
;
375 inst
->SrcReg
[0].Negate
= NEGATE_XYZW
;
376 inst
->SrcReg
[0].Swizzle
= SWIZZLE_XXXX
;
377 inst
->SaturateMode
= SATURATE_ZERO_ONE
;
380 /* LRP result.color.xyz, fogFactorTemp.xxxx, colorTemp, fogColorRef; */
381 inst
->Opcode
= OPCODE_LRP
;
382 inst
->DstReg
.File
= PROGRAM_OUTPUT
;
383 inst
->DstReg
.Index
= FRAG_RESULT_COLOR
;
384 inst
->DstReg
.WriteMask
= WRITEMASK_XYZ
;
385 inst
->SrcReg
[0].File
= PROGRAM_TEMPORARY
;
386 inst
->SrcReg
[0].Index
= fogFactorTemp
;
387 inst
->SrcReg
[0].Swizzle
= SWIZZLE_XXXX
;
388 inst
->SrcReg
[1].File
= PROGRAM_TEMPORARY
;
389 inst
->SrcReg
[1].Index
= colorTemp
;
390 inst
->SrcReg
[1].Swizzle
= SWIZZLE_NOOP
;
391 inst
->SrcReg
[2].File
= PROGRAM_STATE_VAR
;
392 inst
->SrcReg
[2].Index
= fogColorRef
;
393 inst
->SrcReg
[2].Swizzle
= SWIZZLE_NOOP
;
395 /* MOV result.color.w, colorTemp.x; # copy alpha */
396 inst
->Opcode
= OPCODE_MOV
;
397 inst
->DstReg
.File
= PROGRAM_OUTPUT
;
398 inst
->DstReg
.Index
= FRAG_RESULT_COLOR
;
399 inst
->DstReg
.WriteMask
= WRITEMASK_W
;
400 inst
->SrcReg
[0].File
= PROGRAM_TEMPORARY
;
401 inst
->SrcReg
[0].Index
= colorTemp
;
402 inst
->SrcReg
[0].Swizzle
= SWIZZLE_NOOP
;
405 inst
->Opcode
= OPCODE_END
;
408 /* free old instructions */
409 _mesa_free_instructions(fprog
->Base
.Instructions
, origLen
);
411 /* install new instructions */
412 fprog
->Base
.Instructions
= newInst
;
413 fprog
->Base
.NumInstructions
= inst
- newInst
;
414 fprog
->Base
.InputsRead
|= VARYING_BIT_FOGC
;
415 assert(fprog
->Base
.OutputsWritten
& (1 << FRAG_RESULT_COLOR
));
421 is_texture_instruction(const struct prog_instruction
*inst
)
423 switch (inst
->Opcode
) {
438 * Count the number of texure indirections in the given program.
439 * The program's NumTexIndirections field will be updated.
440 * See the GL_ARB_fragment_program spec (issue 24) for details.
441 * XXX we count texture indirections in texenvprogram.c (maybe use this code
442 * instead and elsewhere).
445 _mesa_count_texture_indirections(struct gl_program
*prog
)
447 GLuint indirections
= 1;
448 GLbitfield tempsOutput
= 0x0;
449 GLbitfield aluTemps
= 0x0;
452 for (i
= 0; i
< prog
->NumInstructions
; i
++) {
453 const struct prog_instruction
*inst
= prog
->Instructions
+ i
;
455 if (is_texture_instruction(inst
)) {
456 if (((inst
->SrcReg
[0].File
== PROGRAM_TEMPORARY
) &&
457 (tempsOutput
& (1 << inst
->SrcReg
[0].Index
))) ||
458 ((inst
->Opcode
!= OPCODE_KIL
) &&
459 (inst
->DstReg
.File
== PROGRAM_TEMPORARY
) &&
460 (aluTemps
& (1 << inst
->DstReg
.Index
))))
469 for (j
= 0; j
< 3; j
++) {
470 if (inst
->SrcReg
[j
].File
== PROGRAM_TEMPORARY
)
471 aluTemps
|= (1 << inst
->SrcReg
[j
].Index
);
473 if (inst
->DstReg
.File
== PROGRAM_TEMPORARY
)
474 aluTemps
|= (1 << inst
->DstReg
.Index
);
477 if ((inst
->Opcode
!= OPCODE_KIL
) && (inst
->DstReg
.File
== PROGRAM_TEMPORARY
))
478 tempsOutput
|= (1 << inst
->DstReg
.Index
);
481 prog
->NumTexIndirections
= indirections
;
486 * Count number of texture instructions in given program and update the
487 * program's NumTexInstructions field.
490 _mesa_count_texture_instructions(struct gl_program
*prog
)
493 prog
->NumTexInstructions
= 0;
494 for (i
= 0; i
< prog
->NumInstructions
; i
++) {
495 prog
->NumTexInstructions
+= is_texture_instruction(prog
->Instructions
+ i
);
501 * Scan/rewrite program to remove reads of custom (output) registers.
502 * The passed type has to be PROGRAM_OUTPUT.
503 * On some hardware, trying to read an output register causes trouble.
504 * So, rewrite the program to use a temporary register in this case.
507 _mesa_remove_output_reads(struct gl_program
*prog
, gl_register_file type
)
510 GLint outputMap
[VARYING_SLOT_MAX
];
511 GLuint numVaryingReads
= 0;
512 GLboolean usedTemps
[MAX_PROGRAM_TEMPS
];
513 GLuint firstTemp
= 0;
515 _mesa_find_used_registers(prog
, PROGRAM_TEMPORARY
,
516 usedTemps
, MAX_PROGRAM_TEMPS
);
518 assert(type
== PROGRAM_OUTPUT
);
520 for (i
= 0; i
< VARYING_SLOT_MAX
; i
++)
523 /* look for instructions which read from varying vars */
524 for (i
= 0; i
< prog
->NumInstructions
; i
++) {
525 struct prog_instruction
*inst
= prog
->Instructions
+ i
;
526 const GLuint numSrc
= _mesa_num_inst_src_regs(inst
->Opcode
);
528 for (j
= 0; j
< numSrc
; j
++) {
529 if (inst
->SrcReg
[j
].File
== type
) {
530 /* replace the read with a temp reg */
531 const GLuint var
= inst
->SrcReg
[j
].Index
;
532 if (outputMap
[var
] == -1) {
534 outputMap
[var
] = _mesa_find_free_register(usedTemps
,
537 firstTemp
= outputMap
[var
] + 1;
539 inst
->SrcReg
[j
].File
= PROGRAM_TEMPORARY
;
540 inst
->SrcReg
[j
].Index
= outputMap
[var
];
545 if (numVaryingReads
== 0)
546 return; /* nothing to be done */
548 /* look for instructions which write to the varying vars identified above */
549 for (i
= 0; i
< prog
->NumInstructions
; i
++) {
550 struct prog_instruction
*inst
= prog
->Instructions
+ i
;
551 if (inst
->DstReg
.File
== type
&&
552 outputMap
[inst
->DstReg
.Index
] >= 0) {
553 /* change inst to write to the temp reg, instead of the varying */
554 inst
->DstReg
.File
= PROGRAM_TEMPORARY
;
555 inst
->DstReg
.Index
= outputMap
[inst
->DstReg
.Index
];
559 /* insert new instructions to copy the temp vars to the varying vars */
561 struct prog_instruction
*inst
;
564 /* Look for END instruction and insert the new varying writes */
566 for (i
= 0; i
< prog
->NumInstructions
; i
++) {
567 struct prog_instruction
*inst
= prog
->Instructions
+ i
;
568 if (inst
->Opcode
== OPCODE_END
) {
570 _mesa_insert_instructions(prog
, i
, numVaryingReads
);
577 /* insert new MOV instructions here */
578 inst
= prog
->Instructions
+ endPos
;
579 for (var
= 0; var
< VARYING_SLOT_MAX
; var
++) {
580 if (outputMap
[var
] >= 0) {
581 /* MOV VAR[var], TEMP[tmp]; */
582 inst
->Opcode
= OPCODE_MOV
;
583 inst
->DstReg
.File
= type
;
584 inst
->DstReg
.Index
= var
;
585 inst
->SrcReg
[0].File
= PROGRAM_TEMPORARY
;
586 inst
->SrcReg
[0].Index
= outputMap
[var
];