src/mesa/shader/program.c

   1 /*
   2  * Mesa 3-D graphics library
   3  * Version:  6.5.3
   4  *
   5  * Copyright (C) 1999-2007  Brian Paul   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 "Software"),
   9  * to deal in the Software without restriction, including without limitation
  10  * the rights to use, copy, modify, merge, publish, distribute, sublicense,
  11  * and/or sell copies of the Software, and to permit persons to whom the
  12  * Software is furnished to do so, subject to the following conditions:
  13  *
  14  * The above copyright notice and this permission notice shall be included
  15  * in all copies or substantial portions of the Software.
  16  *
  17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  18  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  19  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
  20  * BRIAN PAUL BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN
  21  * AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  22  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  23  */
  24
  25 /**
  26  * \file program.c
  27  * Vertex and fragment program support functions.
  28  * \author Brian Paul
  29  */
  30
  31
  32 #include "main/glheader.h"
  33 #include "main/context.h"
  34 #include "main/hash.h"
  35 #include "program.h"
  36 #include "prog_cache.h"
  37 #include "prog_parameter.h"
  38 #include "prog_instruction.h"
  39
  40
  41 /**
  42  * A pointer to this dummy program is put into the hash table when
  43  * glGenPrograms is called.
  44  */
  45 struct gl_program _mesa_DummyProgram;
  46
  47
  48 /**
  49  * Init context's vertex/fragment program state
  50  */
  51 void
  52 _mesa_init_program(GLcontext *ctx)
  53 {
  54    GLuint i;
  55
  56    ctx->Program.ErrorPos = -1;
  57    ctx->Program.ErrorString = _mesa_strdup("");
  58
  59 #if FEATURE_NV_vertex_program || FEATURE_ARB_vertex_program
  60    ctx->VertexProgram.Enabled = GL_FALSE;
  61 #if FEATURE_es2_glsl
  62    ctx->VertexProgram.PointSizeEnabled = GL_TRUE;
  63 #else
  64    ctx->VertexProgram.PointSizeEnabled = GL_FALSE;
  65 #endif
  66    ctx->VertexProgram.TwoSideEnabled = GL_FALSE;
  67    _mesa_reference_vertprog(ctx, &ctx->VertexProgram.Current,
  68                             ctx->Shared->DefaultVertexProgram);
  69    assert(ctx->VertexProgram.Current);
  70    for (i = 0; i < MAX_NV_VERTEX_PROGRAM_PARAMS / 4; i++) {
  71       ctx->VertexProgram.TrackMatrix[i] = GL_NONE;
  72       ctx->VertexProgram.TrackMatrixTransform[i] = GL_IDENTITY_NV;
  73    }
  74    ctx->VertexProgram.Cache = _mesa_new_program_cache();
  75 #endif
  76
  77 #if FEATURE_NV_fragment_program || FEATURE_ARB_fragment_program
  78    ctx->FragmentProgram.Enabled = GL_FALSE;
  79    _mesa_reference_fragprog(ctx, &ctx->FragmentProgram.Current,
  80                             ctx->Shared->DefaultFragmentProgram);
  81    assert(ctx->FragmentProgram.Current);
  82    ctx->FragmentProgram.Cache = _mesa_new_program_cache();
  83 #endif
  84
  85
  86    /* XXX probably move this stuff */
  87 #if FEATURE_ATI_fragment_shader
  88    ctx->ATIFragmentShader.Enabled = GL_FALSE;
  89    ctx->ATIFragmentShader.Current = ctx->Shared->DefaultFragmentShader;
  90    assert(ctx->ATIFragmentShader.Current);
  91    ctx->ATIFragmentShader.Current->RefCount++;
  92 #endif
  93 }
  94
  95
  96 /**
  97  * Free a context's vertex/fragment program state
  98  */
  99 void
 100 _mesa_free_program_data(GLcontext *ctx)
 101 {
 102 #if FEATURE_NV_vertex_program || FEATURE_ARB_vertex_program
 103    _mesa_reference_vertprog(ctx, &ctx->VertexProgram.Current, NULL);
 104    _mesa_delete_program_cache(ctx, ctx->VertexProgram.Cache);
 105 #endif
 106 #if FEATURE_NV_fragment_program || FEATURE_ARB_fragment_program
 107    _mesa_reference_fragprog(ctx, &ctx->FragmentProgram.Current, NULL);
 108    _mesa_delete_program_cache(ctx, ctx->FragmentProgram.Cache);
 109 #endif
 110    /* XXX probably move this stuff */
 111 #if FEATURE_ATI_fragment_shader
 112    if (ctx->ATIFragmentShader.Current) {
 113       ctx->ATIFragmentShader.Current->RefCount--;
 114       if (ctx->ATIFragmentShader.Current->RefCount <= 0) {
 115          _mesa_free(ctx->ATIFragmentShader.Current);
 116       }
 117    }
 118 #endif
 119    _mesa_free((void *) ctx->Program.ErrorString);
 120 }
 121
 122
 123 /**
 124  * Update the default program objects in the given context to reference those
 125  * specified in the shared state and release those referencing the old
 126  * shared state.
 127  */
 128 void
 129 _mesa_update_default_objects_program(GLcontext *ctx)
 130 {
 131 #if FEATURE_NV_vertex_program || FEATURE_ARB_vertex_program
 132    _mesa_reference_vertprog(ctx, &ctx->VertexProgram.Current,
 133                             (struct gl_vertex_program *)
 134                             ctx->Shared->DefaultVertexProgram);
 135    assert(ctx->VertexProgram.Current);
 136 #endif
 137
 138 #if FEATURE_NV_fragment_program || FEATURE_ARB_fragment_program
 139    _mesa_reference_fragprog(ctx, &ctx->FragmentProgram.Current,
 140                             (struct gl_fragment_program *)
 141                             ctx->Shared->DefaultFragmentProgram);
 142    assert(ctx->FragmentProgram.Current);
 143 #endif
 144
 145    /* XXX probably move this stuff */
 146 #if FEATURE_ATI_fragment_shader
 147    if (ctx->ATIFragmentShader.Current) {
 148       ctx->ATIFragmentShader.Current->RefCount--;
 149       if (ctx->ATIFragmentShader.Current->RefCount <= 0) {
 150          _mesa_free(ctx->ATIFragmentShader.Current);
 151       }
 152    }
 153    ctx->ATIFragmentShader.Current = (struct ati_fragment_shader *) ctx->Shared->DefaultFragmentShader;
 154    assert(ctx->ATIFragmentShader.Current);
 155    ctx->ATIFragmentShader.Current->RefCount++;
 156 #endif
 157 }
 158
 159
 160 /**
 161  * Set the vertex/fragment program error state (position and error string).
 162  * This is generally called from within the parsers.
 163  */
 164 void
 165 _mesa_set_program_error(GLcontext *ctx, GLint pos, const char *string)
 166 {
 167    ctx->Program.ErrorPos = pos;
 168    _mesa_free((void *) ctx->Program.ErrorString);
 169    if (!string)
 170       string = "";
 171    ctx->Program.ErrorString = _mesa_strdup(string);
 172 }
 173
 174
 175 /**
 176  * Find the line number and column for 'pos' within 'string'.
 177  * Return a copy of the line which contains 'pos'.  Free the line with
 178  * _mesa_free().
 179  * \param string  the program string
 180  * \param pos     the position within the string
 181  * \param line    returns the line number corresponding to 'pos'.
 182  * \param col     returns the column number corresponding to 'pos'.
 183  * \return copy of the line containing 'pos'.
 184  */
 185 const GLubyte *
 186 _mesa_find_line_column(const GLubyte *string, const GLubyte *pos,
 187                        GLint *line, GLint *col)
 188 {
 189    const GLubyte *lineStart = string;
 190    const GLubyte *p = string;
 191    GLubyte *s;
 192    int len;
 193
 194    *line = 1;
 195
 196    while (p != pos) {
 197       if (*p == (GLubyte) '\n') {
 198          (*line)++;
 199          lineStart = p + 1;
 200       }
 201       p++;
 202    }
 203
 204    *col = (pos - lineStart) + 1;
 205
 206    /* return copy of this line */
 207    while (*p != 0 && *p != '\n')
 208       p++;
 209    len = p - lineStart;
 210    s = (GLubyte *) _mesa_malloc(len + 1);
 211    _mesa_memcpy(s, lineStart, len);
 212    s[len] = 0;
 213
 214    return s;
 215 }
 216
 217
 218 /**
 219  * Initialize a new vertex/fragment program object.
 220  */
 221 static struct gl_program *
 222 _mesa_init_program_struct( GLcontext *ctx, struct gl_program *prog,
 223                            GLenum target, GLuint id)
 224 {
 225    (void) ctx;
 226    if (prog) {
 227       GLuint i;
 228       _mesa_bzero(prog, sizeof(*prog));
 229       prog->Id = id;
 230       prog->Target = target;
 231       prog->Resident = GL_TRUE;
 232       prog->RefCount = 1;
 233       prog->Format = GL_PROGRAM_FORMAT_ASCII_ARB;
 234
 235       /* default mapping from samplers to texture units */
 236       for (i = 0; i < MAX_SAMPLERS; i++)
 237          prog->SamplerUnits[i] = i;
 238    }
 239
 240    return prog;
 241 }
 242
 243
 244 /**
 245  * Initialize a new fragment program object.
 246  */
 247 struct gl_program *
 248 _mesa_init_fragment_program( GLcontext *ctx, struct gl_fragment_program *prog,
 249                              GLenum target, GLuint id)
 250 {
 251    if (prog)
 252       return _mesa_init_program_struct( ctx, &prog->Base, target, id );
 253    else
 254       return NULL;
 255 }
 256
 257
 258 /**
 259  * Initialize a new vertex program object.
 260  */
 261 struct gl_program *
 262 _mesa_init_vertex_program( GLcontext *ctx, struct gl_vertex_program *prog,
 263                            GLenum target, GLuint id)
 264 {
 265    if (prog)
 266       return _mesa_init_program_struct( ctx, &prog->Base, target, id );
 267    else
 268       return NULL;
 269 }
 270
 271
 272 /**
 273  * Allocate and initialize a new fragment/vertex program object but
 274  * don't put it into the program hash table.  Called via
 275  * ctx->Driver.NewProgram.  May be overridden (ie. replaced) by a
 276  * device driver function to implement OO deriviation with additional
 277  * types not understood by this function.
 278  *
 279  * \param ctx  context
 280  * \param id   program id/number
 281  * \param target  program target/type
 282  * \return  pointer to new program object
 283  */
 284 struct gl_program *
 285 _mesa_new_program(GLcontext *ctx, GLenum target, GLuint id)
 286 {
 287    struct gl_program *prog;
 288    switch (target) {
 289    case GL_VERTEX_PROGRAM_ARB: /* == GL_VERTEX_PROGRAM_NV */
 290       prog = _mesa_init_vertex_program(ctx, CALLOC_STRUCT(gl_vertex_program),
 291                                        target, id );
 292       break;
 293    case GL_FRAGMENT_PROGRAM_NV:
 294    case GL_FRAGMENT_PROGRAM_ARB:
 295       prog =_mesa_init_fragment_program(ctx,
 296                                          CALLOC_STRUCT(gl_fragment_program),
 297                                          target, id );
 298       break;
 299    default:
 300       _mesa_problem(ctx, "bad target in _mesa_new_program");
 301       prog = NULL;
 302    }
 303    return prog;
 304 }
 305
 306
 307 /**
 308  * Delete a program and remove it from the hash table, ignoring the
 309  * reference count.
 310  * Called via ctx->Driver.DeleteProgram.  May be wrapped (OO deriviation)
 311  * by a device driver function.
 312  */
 313 void
 314 _mesa_delete_program(GLcontext *ctx, struct gl_program *prog)
 315 {
 316    (void) ctx;
 317    ASSERT(prog);
 318    ASSERT(prog->RefCount==0);
 319
 320    if (prog == &_mesa_DummyProgram)
 321       return;
 322
 323    if (prog->String)
 324       _mesa_free(prog->String);
 325
 326    _mesa_free_instructions(prog->Instructions, prog->NumInstructions);
 327
 328    if (prog->Parameters) {
 329       _mesa_free_parameter_list(prog->Parameters);
 330    }
 331    if (prog->Varying) {
 332       _mesa_free_parameter_list(prog->Varying);
 333    }
 334    if (prog->Attributes) {
 335       _mesa_free_parameter_list(prog->Attributes);
 336    }
 337
 338    /* XXX this is a little ugly */
 339    if (prog->Target == GL_VERTEX_PROGRAM_ARB) {
 340       struct gl_vertex_program *vprog = (struct gl_vertex_program *) prog;
 341       if (vprog->TnlData)
 342          _mesa_free(vprog->TnlData);
 343    }
 344
 345    _mesa_free(prog);
 346 }
 347
 348
 349 /**
 350  * Return the gl_program object for a given ID.
 351  * Basically just a wrapper for _mesa_HashLookup() to avoid a lot of
 352  * casts elsewhere.
 353  */
 354 struct gl_program *
 355 _mesa_lookup_program(GLcontext *ctx, GLuint id)
 356 {
 357    if (id)
 358       return (struct gl_program *) _mesa_HashLookup(ctx->Shared->Programs, id);
 359    else
 360       return NULL;
 361 }
 362
 363
 364 /**
 365  * Reference counting for vertex/fragment programs
 366  */
 367 void
 368 _mesa_reference_program(GLcontext *ctx,
 369                         struct gl_program **ptr,
 370                         struct gl_program *prog)
 371 {
 372    assert(ptr);
 373    if (*ptr && prog) {
 374       /* sanity check */
 375       if ((*ptr)->Target == GL_VERTEX_PROGRAM_ARB)
 376          ASSERT(prog->Target == GL_VERTEX_PROGRAM_ARB);
 377       else if ((*ptr)->Target == GL_FRAGMENT_PROGRAM_ARB)
 378          ASSERT(prog->Target == GL_FRAGMENT_PROGRAM_ARB ||
 379                 prog->Target == GL_FRAGMENT_PROGRAM_NV);
 380    }
 381    if (*ptr == prog) {
 382       return;  /* no change */
 383    }
 384    if (*ptr) {
 385       GLboolean deleteFlag;
 386
 387       /*_glthread_LOCK_MUTEX((*ptr)->Mutex);*/
 388 #if 0
 389       printf("Program %p ID=%u Target=%s  Refcount-- to %d\n",
 390              *ptr, (*ptr)->Id,
 391              ((*ptr)->Target == GL_VERTEX_PROGRAM_ARB ? "VP" : "FP"),
 392              (*ptr)->RefCount - 1);
 393 #endif
 394       ASSERT((*ptr)->RefCount > 0);
 395       (*ptr)->RefCount--;
 396
 397       deleteFlag = ((*ptr)->RefCount == 0);
 398       /*_glthread_UNLOCK_MUTEX((*ptr)->Mutex);*/
 399
 400       if (deleteFlag) {
 401          ASSERT(ctx);
 402          ctx->Driver.DeleteProgram(ctx, *ptr);
 403       }
 404
 405       *ptr = NULL;
 406    }
 407
 408    assert(!*ptr);
 409    if (prog) {
 410       /*_glthread_LOCK_MUTEX(prog->Mutex);*/
 411       prog->RefCount++;
 412 #if 0
 413       printf("Program %p ID=%u Target=%s  Refcount++ to %d\n",
 414              prog, prog->Id,
 415              (prog->Target == GL_VERTEX_PROGRAM_ARB ? "VP" : "FP"),
 416              prog->RefCount);
 417 #endif
 418       /*_glthread_UNLOCK_MUTEX(prog->Mutex);*/
 419    }
 420
 421    *ptr = prog;
 422 }
 423
 424
 425 /**
 426  * Return a copy of a program.
 427  * XXX Problem here if the program object is actually OO-derivation
 428  * made by a device driver.
 429  */
 430 struct gl_program *
 431 _mesa_clone_program(GLcontext *ctx, const struct gl_program *prog)
 432 {
 433    struct gl_program *clone;
 434
 435    clone = ctx->Driver.NewProgram(ctx, prog->Target, prog->Id);
 436    if (!clone)
 437       return NULL;
 438
 439    assert(clone->Target == prog->Target);
 440    assert(clone->RefCount == 1);
 441
 442    clone->String = (GLubyte *) _mesa_strdup((char *) prog->String);
 443    clone->Format = prog->Format;
 444    clone->Instructions = _mesa_alloc_instructions(prog->NumInstructions);
 445    if (!clone->Instructions) {
 446       _mesa_reference_program(ctx, &clone, NULL);
 447       return NULL;
 448    }
 449    _mesa_copy_instructions(clone->Instructions, prog->Instructions,
 450                            prog->NumInstructions);
 451    clone->InputsRead = prog->InputsRead;
 452    clone->OutputsWritten = prog->OutputsWritten;
 453    clone->SamplersUsed = prog->SamplersUsed;
 454    clone->ShadowSamplers = prog->ShadowSamplers;
 455    memcpy(clone->TexturesUsed, prog->TexturesUsed, sizeof(prog->TexturesUsed));
 456
 457    if (prog->Parameters)
 458       clone->Parameters = _mesa_clone_parameter_list(prog->Parameters);
 459    memcpy(clone->LocalParams, prog->LocalParams, sizeof(clone->LocalParams));
 460    if (prog->Varying)
 461       clone->Varying = _mesa_clone_parameter_list(prog->Varying);
 462    if (prog->Attributes)
 463       clone->Attributes = _mesa_clone_parameter_list(prog->Attributes);
 464    memcpy(clone->LocalParams, prog->LocalParams, sizeof(clone->LocalParams));
 465    clone->NumInstructions = prog->NumInstructions;
 466    clone->NumTemporaries = prog->NumTemporaries;
 467    clone->NumParameters = prog->NumParameters;
 468    clone->NumAttributes = prog->NumAttributes;
 469    clone->NumAddressRegs = prog->NumAddressRegs;
 470    clone->NumNativeInstructions = prog->NumNativeInstructions;
 471    clone->NumNativeTemporaries = prog->NumNativeTemporaries;
 472    clone->NumNativeParameters = prog->NumNativeParameters;
 473    clone->NumNativeAttributes = prog->NumNativeAttributes;
 474    clone->NumNativeAddressRegs = prog->NumNativeAddressRegs;
 475    clone->NumAluInstructions = prog->NumAluInstructions;
 476    clone->NumTexInstructions = prog->NumTexInstructions;
 477    clone->NumTexIndirections = prog->NumTexIndirections;
 478    clone->NumNativeAluInstructions = prog->NumNativeAluInstructions;
 479    clone->NumNativeTexInstructions = prog->NumNativeTexInstructions;
 480    clone->NumNativeTexIndirections = prog->NumNativeTexIndirections;
 481
 482    switch (prog->Target) {
 483    case GL_VERTEX_PROGRAM_ARB:
 484       {
 485          const struct gl_vertex_program *vp
 486             = (const struct gl_vertex_program *) prog;
 487          struct gl_vertex_program *vpc = (struct gl_vertex_program *) clone;
 488          vpc->IsPositionInvariant = vp->IsPositionInvariant;
 489       }
 490       break;
 491    case GL_FRAGMENT_PROGRAM_ARB:
 492       {
 493          const struct gl_fragment_program *fp
 494             = (const struct gl_fragment_program *) prog;
 495          struct gl_fragment_program *fpc = (struct gl_fragment_program *) clone;
 496          fpc->FogOption = fp->FogOption;
 497          fpc->UsesKill = fp->UsesKill;
 498       }
 499       break;
 500    default:
 501       _mesa_problem(NULL, "Unexpected target in _mesa_clone_program");
 502    }
 503
 504    return clone;
 505 }
 506
 507
 508 /**
 509  * Insert 'count' NOP instructions at 'start' in the given program.
 510  * Adjust branch targets accordingly.
 511  */
 512 GLboolean
 513 _mesa_insert_instructions(struct gl_program *prog, GLuint start, GLuint count)
 514 {
 515    const GLuint origLen = prog->NumInstructions;
 516    const GLuint newLen = origLen + count;
 517    struct prog_instruction *newInst;
 518    GLuint i;
 519
 520    /* adjust branches */
 521    for (i = 0; i < prog->NumInstructions; i++) {
 522       struct prog_instruction *inst = prog->Instructions + i;
 523       if (inst->BranchTarget > 0) {
 524          if ((GLuint)inst->BranchTarget >= start) {
 525             inst->BranchTarget += count;
 526          }
 527       }
 528    }
 529
 530    /* Alloc storage for new instructions */
 531    newInst = _mesa_alloc_instructions(newLen);
 532    if (!newInst) {
 533       return GL_FALSE;
 534    }
 535
 536    /* Copy 'start' instructions into new instruction buffer */
 537    _mesa_copy_instructions(newInst, prog->Instructions, start);
 538
 539    /* init the new instructions */
 540    _mesa_init_instructions(newInst + start, count);
 541
 542    /* Copy the remaining/tail instructions to new inst buffer */
 543    _mesa_copy_instructions(newInst + start + count,
 544                            prog->Instructions + start,
 545                            origLen - start);
 546
 547    /* free old instructions */
 548    _mesa_free_instructions(prog->Instructions, origLen);
 549
 550    /* install new instructions */
 551    prog->Instructions = newInst;
 552    prog->NumInstructions = newLen;
 553
 554    return GL_TRUE;
 555 }
 556
 557 /**
 558  * Delete 'count' instructions at 'start' in the given program.
 559  * Adjust branch targets accordingly.
 560  */
 561 GLboolean
 562 _mesa_delete_instructions(struct gl_program *prog, GLuint start, GLuint count)
 563 {
 564    const GLuint origLen = prog->NumInstructions;
 565    const GLuint newLen = origLen - count;
 566    struct prog_instruction *newInst;
 567    GLuint i;
 568
 569    /* adjust branches */
 570    for (i = 0; i < prog->NumInstructions; i++) {
 571       struct prog_instruction *inst = prog->Instructions + i;
 572       if (inst->BranchTarget > 0) {
 573          if (inst->BranchTarget > start) {
 574             inst->BranchTarget -= count;
 575          }
 576       }
 577    }
 578
 579    /* Alloc storage for new instructions */
 580    newInst = _mesa_alloc_instructions(newLen);
 581    if (!newInst) {
 582       return GL_FALSE;
 583    }
 584
 585    /* Copy 'start' instructions into new instruction buffer */
 586    _mesa_copy_instructions(newInst, prog->Instructions, start);
 587
 588    /* Copy the remaining/tail instructions to new inst buffer */
 589    _mesa_copy_instructions(newInst + start,
 590                            prog->Instructions + start + count,
 591                            newLen - start);
 592
 593    /* free old instructions */
 594    _mesa_free_instructions(prog->Instructions, origLen);
 595
 596    /* install new instructions */
 597    prog->Instructions = newInst;
 598    prog->NumInstructions = newLen;
 599
 600    return GL_TRUE;
 601 }
 602
 603
 604 /**
 605  * Search instructions for registers that match (oldFile, oldIndex),
 606  * replacing them with (newFile, newIndex).
 607  */
 608 static void
 609 replace_registers(struct prog_instruction *inst, GLuint numInst,
 610                   GLuint oldFile, GLuint oldIndex,
 611                   GLuint newFile, GLuint newIndex)
 612 {
 613    GLuint i, j;
 614    for (i = 0; i < numInst; i++) {
 615       /* src regs */
 616       for (j = 0; j < _mesa_num_inst_src_regs(inst->Opcode); j++) {
 617          if (inst[i].SrcReg[j].File == oldFile &&
 618              inst[i].SrcReg[j].Index == oldIndex) {
 619             inst[i].SrcReg[j].File = newFile;
 620             inst[i].SrcReg[j].Index = newIndex;
 621          }
 622       }
 623       /* dst reg */
 624       if (inst[i].DstReg.File == oldFile && inst[i].DstReg.Index == oldIndex) {
 625          inst[i].DstReg.File = newFile;
 626          inst[i].DstReg.Index = newIndex;
 627       }
 628    }
 629 }
 630
 631
 632 /**
 633  * Search instructions for references to program parameters.  When found,
 634  * increment the parameter index by 'offset'.
 635  * Used when combining programs.
 636  */
 637 static void
 638 adjust_param_indexes(struct prog_instruction *inst, GLuint numInst,
 639                      GLuint offset)
 640 {
 641    GLuint i, j;
 642    for (i = 0; i < numInst; i++) {
 643       for (j = 0; j < _mesa_num_inst_src_regs(inst->Opcode); j++) {
 644          GLuint f = inst[i].SrcReg[j].File;
 645          if (f == PROGRAM_CONSTANT ||
 646              f == PROGRAM_UNIFORM ||
 647              f == PROGRAM_STATE_VAR) {
 648             inst[i].SrcReg[j].Index += offset;
 649          }
 650       }
 651    }
 652 }
 653
 654
 655 /**
 656  * Combine two programs into one.  Fix instructions so the outputs of
 657  * the first program go to the inputs of the second program.
 658  */
 659 struct gl_program *
 660 _mesa_combine_programs(GLcontext *ctx,
 661                        const struct gl_program *progA,
 662                        const struct gl_program *progB)
 663 {
 664    struct prog_instruction *newInst;
 665    struct gl_program *newProg;
 666    const GLuint lenA = progA->NumInstructions - 1; /* omit END instr */
 667    const GLuint lenB = progB->NumInstructions;
 668    const GLuint numParamsA = _mesa_num_parameters(progA->Parameters);
 669    const GLuint newLength = lenA + lenB;
 670    GLbitfield inputsB;
 671    GLuint i;
 672
 673    ASSERT(progA->Target == progB->Target);
 674
 675    newInst = _mesa_alloc_instructions(newLength);
 676    if (!newInst)
 677       return GL_FALSE;
 678
 679    _mesa_copy_instructions(newInst, progA->Instructions, lenA);
 680    _mesa_copy_instructions(newInst + lenA, progB->Instructions, lenB);
 681
 682    /* adjust branch / instruction addresses for B's instructions */
 683    for (i = 0; i < lenB; i++) {
 684       newInst[lenA + i].BranchTarget += lenA;
 685    }
 686
 687    newProg = ctx->Driver.NewProgram(ctx, progA->Target, 0);
 688    newProg->Instructions = newInst;
 689    newProg->NumInstructions = newLength;
 690
 691    if (newProg->Target == GL_FRAGMENT_PROGRAM_ARB) {
 692       struct gl_fragment_program *fprogA, *fprogB, *newFprog;
 693       GLbitfield progB_inputsRead = progB->InputsRead;
 694       GLint progB_colorFile, progB_colorIndex;
 695
 696       fprogA = (struct gl_fragment_program *) progA;
 697       fprogB = (struct gl_fragment_program *) progB;
 698       newFprog = (struct gl_fragment_program *) newProg;
 699
 700       newFprog->UsesKill = fprogA->UsesKill || fprogB->UsesKill;
 701
 702       /* We'll do a search and replace for instances
 703        * of progB_colorFile/progB_colorIndex below...
 704        */
 705       progB_colorFile = PROGRAM_INPUT;
 706       progB_colorIndex = FRAG_ATTRIB_COL0;
 707
 708       /*
 709        * The fragment program may get color from a state var rather than
 710        * a fragment input (vertex output) if it's constant.
 711        * See the texenvprogram.c code.
 712        * So, search the program's parameter list now to see if the program
 713        * gets color from a state var instead of a conventional fragment
 714        * input register.
 715        */
 716       for (i = 0; i < progB->Parameters->NumParameters; i++) {
 717          struct gl_program_parameter *p = &progB->Parameters->Parameters[i];
 718          if (p->Type == PROGRAM_STATE_VAR &&
 719              p->StateIndexes[0] == STATE_INTERNAL &&
 720              p->StateIndexes[1] == STATE_CURRENT_ATTRIB &&
 721              p->StateIndexes[2] == VERT_ATTRIB_COLOR0) {
 722             progB_inputsRead |= FRAG_BIT_COL0;
 723             progB_colorFile = PROGRAM_STATE_VAR;
 724             progB_colorIndex = i;
 725             break;
 726          }
 727       }
 728
 729       /* Connect color outputs of fprogA to color inputs of fprogB, via a
 730        * new temporary register.
 731        */
 732       if ((progA->OutputsWritten & (1 << FRAG_RESULT_COLR)) &&
 733           (progB_inputsRead & FRAG_BIT_COL0)) {
 734          GLint tempReg = _mesa_find_free_register(newProg, PROGRAM_TEMPORARY);
 735          if (tempReg < 0) {
 736             _mesa_problem(ctx, "No free temp regs found in "
 737                           "_mesa_combine_programs(), using 31");
 738             tempReg = 31;
 739          }
 740          /* replace writes to result.color[0] with tempReg */
 741          replace_registers(newInst, lenA,
 742                            PROGRAM_OUTPUT, FRAG_RESULT_COLR,
 743                            PROGRAM_TEMPORARY, tempReg);
 744          /* replace reads from the input color with tempReg */
 745          replace_registers(newInst + lenA, lenB,
 746                            progB_colorFile, progB_colorIndex, /* search for */
 747                            PROGRAM_TEMPORARY, tempReg  /* replace with */ );
 748       }
 749
 750       /* compute combined program's InputsRead */
 751       inputsB = progB_inputsRead;
 752       if (progA->OutputsWritten & (1 << FRAG_RESULT_COLR)) {
 753          inputsB &= ~(1 << FRAG_ATTRIB_COL0);
 754       }
 755       newProg->InputsRead = progA->InputsRead | inputsB;
 756       newProg->OutputsWritten = progB->OutputsWritten;
 757       newProg->SamplersUsed = progA->SamplersUsed | progB->SamplersUsed;
 758    }
 759    else {
 760       /* vertex program */
 761       assert(0);      /* XXX todo */
 762    }
 763
 764    /*
 765     * Merge parameters (uniforms, constants, etc)
 766     */
 767    newProg->Parameters = _mesa_combine_parameter_lists(progA->Parameters,
 768                                                        progB->Parameters);
 769
 770    adjust_param_indexes(newInst + lenA, lenB, numParamsA);
 771
 772
 773    return newProg;
 774 }
 775
 776
 777
 778
 779 /**
 780  * Scan the given program to find a free register of the given type.
 781  * \param regFile - PROGRAM_INPUT, PROGRAM_OUTPUT or PROGRAM_TEMPORARY
 782  */
 783 GLint
 784 _mesa_find_free_register(const struct gl_program *prog, GLuint regFile)
 785 {
 786    GLboolean used[MAX_PROGRAM_TEMPS];
 787    GLuint i, k;
 788
 789    assert(regFile == PROGRAM_INPUT ||
 790           regFile == PROGRAM_OUTPUT ||
 791           regFile == PROGRAM_TEMPORARY);
 792
 793    _mesa_memset(used, 0, sizeof(used));
 794
 795    for (i = 0; i < prog->NumInstructions; i++) {
 796       const struct prog_instruction *inst = prog->Instructions + i;
 797       const GLuint n = _mesa_num_inst_src_regs(inst->Opcode);
 798
 799       for (k = 0; k < n; k++) {
 800          if (inst->SrcReg[k].File == regFile) {
 801             used[inst->SrcReg[k].Index] = GL_TRUE;
 802          }
 803       }
 804    }
 805
 806    for (i = 0; i < MAX_PROGRAM_TEMPS; i++) {
 807       if (!used[i])
 808          return i;
 809    }
 810
 811    return -1;
 812 }