src/mesa/drivers/dri/i965/brw_vs.c

   1 /*
   2  Copyright (C) Intel Corp.  2006.  All Rights Reserved.
   3  Intel funded Tungsten Graphics to
   4  develop this 3D driver.
   5
   6  Permission is hereby granted, free of charge, to any person obtaining
   7  a 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, sublicense, 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
  16  portions of the Software.
  17
  18  THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  19  EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  20  MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
  21  IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
  22  LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  23  OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  24  WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25
  26  **********************************************************************/
  27  /*
  28   * Authors:
  29   *   Keith Whitwell <keithw@vmware.com>
  30   */
  31
  32
  33 #include "main/compiler.h"
  34 #include "brw_context.h"
  35 #include "brw_vs.h"
  36 #include "brw_util.h"
  37 #include "brw_state.h"
  38 #include "program/prog_print.h"
  39 #include "program/prog_parameter.h"
  40
  41 #include "util/ralloc.h"
  42
  43 static inline void assign_vue_slot(struct brw_vue_map *vue_map,
  44                                    int varying)
  45 {
  46    /* Make sure this varying hasn't been assigned a slot already */
  47    assert (vue_map->varying_to_slot[varying] == -1);
  48
  49    vue_map->varying_to_slot[varying] = vue_map->num_slots;
  50    vue_map->slot_to_varying[vue_map->num_slots++] = varying;
  51 }
  52
  53 /**
  54  * Compute the VUE map for vertex shader program.
  55  */
  56 void
  57 brw_compute_vue_map(struct brw_context *brw, struct brw_vue_map *vue_map,
  58                     GLbitfield64 slots_valid)
  59 {
  60    vue_map->slots_valid = slots_valid;
  61    int i;
  62
  63    /* gl_Layer and gl_ViewportIndex don't get their own varying slots -- they
  64     * are stored in the first VUE slot (VARYING_SLOT_PSIZ).
  65     */
  66    slots_valid &= ~(VARYING_BIT_LAYER | VARYING_BIT_VIEWPORT);
  67
  68    /* Make sure that the values we store in vue_map->varying_to_slot and
  69     * vue_map->slot_to_varying won't overflow the signed chars that are used
  70     * to store them.  Note that since vue_map->slot_to_varying sometimes holds
  71     * values equal to BRW_VARYING_SLOT_COUNT, we need to ensure that
  72     * BRW_VARYING_SLOT_COUNT is <= 127, not 128.
  73     */
  74    STATIC_ASSERT(BRW_VARYING_SLOT_COUNT <= 127);
  75
  76    vue_map->num_slots = 0;
  77    for (i = 0; i < BRW_VARYING_SLOT_COUNT; ++i) {
  78       vue_map->varying_to_slot[i] = -1;
  79       vue_map->slot_to_varying[i] = BRW_VARYING_SLOT_COUNT;
  80    }
  81
  82    /* VUE header: format depends on chip generation and whether clipping is
  83     * enabled.
  84     */
  85    if (brw->gen < 6) {
  86       /* There are 8 dwords in VUE header pre-Ironlake:
  87        * dword 0-3 is indices, point width, clip flags.
  88        * dword 4-7 is ndc position
  89        * dword 8-11 is the first vertex data.
  90        *
  91        * On Ironlake the VUE header is nominally 20 dwords, but the hardware
  92        * will accept the same header layout as Gen4 [and should be a bit faster]
  93        */
  94       assign_vue_slot(vue_map, VARYING_SLOT_PSIZ);
  95       assign_vue_slot(vue_map, BRW_VARYING_SLOT_NDC);
  96       assign_vue_slot(vue_map, VARYING_SLOT_POS);
  97    } else {
  98       /* There are 8 or 16 DWs (D0-D15) in VUE header on Sandybridge:
  99        * dword 0-3 of the header is indices, point width, clip flags.
 100        * dword 4-7 is the 4D space position
 101        * dword 8-15 of the vertex header is the user clip distance if
 102        * enabled.
 103        * dword 8-11 or 16-19 is the first vertex element data we fill.
 104        */
 105       assign_vue_slot(vue_map, VARYING_SLOT_PSIZ);
 106       assign_vue_slot(vue_map, VARYING_SLOT_POS);
 107       if (slots_valid & BITFIELD64_BIT(VARYING_SLOT_CLIP_DIST0))
 108          assign_vue_slot(vue_map, VARYING_SLOT_CLIP_DIST0);
 109       if (slots_valid & BITFIELD64_BIT(VARYING_SLOT_CLIP_DIST1))
 110          assign_vue_slot(vue_map, VARYING_SLOT_CLIP_DIST1);
 111
 112       /* front and back colors need to be consecutive so that we can use
 113        * ATTRIBUTE_SWIZZLE_INPUTATTR_FACING to swizzle them when doing
 114        * two-sided color.
 115        */
 116       if (slots_valid & BITFIELD64_BIT(VARYING_SLOT_COL0))
 117          assign_vue_slot(vue_map, VARYING_SLOT_COL0);
 118       if (slots_valid & BITFIELD64_BIT(VARYING_SLOT_BFC0))
 119          assign_vue_slot(vue_map, VARYING_SLOT_BFC0);
 120       if (slots_valid & BITFIELD64_BIT(VARYING_SLOT_COL1))
 121          assign_vue_slot(vue_map, VARYING_SLOT_COL1);
 122       if (slots_valid & BITFIELD64_BIT(VARYING_SLOT_BFC1))
 123          assign_vue_slot(vue_map, VARYING_SLOT_BFC1);
 124    }
 125
 126    /* The hardware doesn't care about the rest of the vertex outputs, so just
 127     * assign them contiguously.  Don't reassign outputs that already have a
 128     * slot.
 129     *
 130     * We generally don't need to assign a slot for VARYING_SLOT_CLIP_VERTEX,
 131     * since it's encoded as the clip distances by emit_clip_distances().
 132     * However, it may be output by transform feedback, and we'd rather not
 133     * recompute state when TF changes, so we just always include it.
 134     */
 135    for (int i = 0; i < VARYING_SLOT_MAX; ++i) {
 136       if ((slots_valid & BITFIELD64_BIT(i)) &&
 137           vue_map->varying_to_slot[i] == -1) {
 138          assign_vue_slot(vue_map, i);
 139       }
 140    }
 141 }
 142
 143
 144 /**
 145  * Decide which set of clip planes should be used when clipping via
 146  * gl_Position or gl_ClipVertex.
 147  */
 148 gl_clip_plane *brw_select_clip_planes(struct gl_context *ctx)
 149 {
 150    if (ctx->_Shader->CurrentProgram[MESA_SHADER_VERTEX]) {
 151       /* There is currently a GLSL vertex shader, so clip according to GLSL
 152        * rules, which means compare gl_ClipVertex (or gl_Position, if
 153        * gl_ClipVertex wasn't assigned) against the eye-coordinate clip planes
 154        * that were stored in EyeUserPlane at the time the clip planes were
 155        * specified.
 156        */
 157       return ctx->Transform.EyeUserPlane;
 158    } else {
 159       /* Either we are using fixed function or an ARB vertex program.  In
 160        * either case the clip planes are going to be compared against
 161        * gl_Position (which is in clip coordinates) so we have to clip using
 162        * _ClipUserPlane, which was transformed into clip coordinates by Mesa
 163        * core.
 164        */
 165       return ctx->Transform._ClipUserPlane;
 166    }
 167 }
 168
 169
 170 bool
 171 brw_vs_prog_data_compare(const void *in_a, const void *in_b)
 172 {
 173    const struct brw_vs_prog_data *a = in_a;
 174    const struct brw_vs_prog_data *b = in_b;
 175
 176    /* Compare the base structure. */
 177    if (!brw_stage_prog_data_compare(&a->base.base, &b->base.base))
 178       return false;
 179
 180    /* Compare the rest of the struct. */
 181    const unsigned offset = sizeof(struct brw_stage_prog_data);
 182    if (memcmp(((char *) a) + offset, ((char *) b) + offset,
 183               sizeof(struct brw_vs_prog_data) - offset)) {
 184       return false;
 185    }
 186
 187    return true;
 188 }
 189
 190 static bool
 191 do_vs_prog(struct brw_context *brw,
 192            struct gl_shader_program *prog,
 193            struct brw_vertex_program *vp,
 194            struct brw_vs_prog_key *key)
 195 {
 196    GLuint program_size;
 197    const GLuint *program;
 198    struct brw_vs_compile c;
 199    struct brw_vs_prog_data prog_data;
 200    struct brw_stage_prog_data *stage_prog_data = &prog_data.base.base;
 201    void *mem_ctx;
 202    int i;
 203    struct gl_shader *vs = NULL;
 204
 205    if (prog)
 206       vs = prog->_LinkedShaders[MESA_SHADER_VERTEX];
 207
 208    memset(&c, 0, sizeof(c));
 209    memcpy(&c.key, key, sizeof(*key));
 210    memset(&prog_data, 0, sizeof(prog_data));
 211
 212    /* Use ALT floating point mode for ARB programs so that 0^0 == 1. */
 213    if (!prog)
 214       stage_prog_data->use_alt_mode = true;
 215
 216    mem_ctx = ralloc_context(NULL);
 217
 218    c.vp = vp;
 219
 220    /* Allocate the references to the uniforms that will end up in the
 221     * prog_data associated with the compiled program, and which will be freed
 222     * by the state cache.
 223     */
 224    int param_count;
 225    if (vs) {
 226       /* We add padding around uniform values below vec4 size, with the worst
 227        * case being a float value that gets blown up to a vec4, so be
 228        * conservative here.
 229        */
 230       param_count = vs->num_uniform_components * 4;
 231
 232    } else {
 233       param_count = vp->program.Base.Parameters->NumParameters * 4;
 234    }
 235    /* vec4_visitor::setup_uniform_clipplane_values() also uploads user clip
 236     * planes as uniforms.
 237     */
 238    param_count += c.key.base.nr_userclip_plane_consts * 4;
 239
 240    stage_prog_data->param =
 241       rzalloc_array(NULL, const gl_constant_value *, param_count);
 242    stage_prog_data->pull_param =
 243       rzalloc_array(NULL, const gl_constant_value *, param_count);
 244
 245    /* Setting nr_params here NOT to the size of the param and pull_param
 246     * arrays, but to the number of uniform components vec4_visitor
 247     * needs. vec4_visitor::setup_uniforms() will set it back to a proper value.
 248     */
 249    stage_prog_data->nr_params = ALIGN(param_count, 4) / 4;
 250    if (vs) {
 251       stage_prog_data->nr_params += vs->num_samplers;
 252    }
 253
 254    GLbitfield64 outputs_written = vp->program.Base.OutputsWritten;
 255    prog_data.inputs_read = vp->program.Base.InputsRead;
 256
 257    if (c.key.copy_edgeflag) {
 258       outputs_written |= BITFIELD64_BIT(VARYING_SLOT_EDGE);
 259       prog_data.inputs_read |= VERT_BIT_EDGEFLAG;
 260    }
 261
 262    if (brw->gen < 6) {
 263       /* Put dummy slots into the VUE for the SF to put the replaced
 264        * point sprite coords in.  We shouldn't need these dummy slots,
 265        * which take up precious URB space, but it would mean that the SF
 266        * doesn't get nice aligned pairs of input coords into output
 267        * coords, which would be a pain to handle.
 268        */
 269       for (i = 0; i < 8; i++) {
 270          if (c.key.point_coord_replace & (1 << i))
 271             outputs_written |= BITFIELD64_BIT(VARYING_SLOT_TEX0 + i);
 272       }
 273
 274       /* if back colors are written, allocate slots for front colors too */
 275       if (outputs_written & BITFIELD64_BIT(VARYING_SLOT_BFC0))
 276          outputs_written |= BITFIELD64_BIT(VARYING_SLOT_COL0);
 277       if (outputs_written & BITFIELD64_BIT(VARYING_SLOT_BFC1))
 278          outputs_written |= BITFIELD64_BIT(VARYING_SLOT_COL1);
 279    }
 280
 281    /* In order for legacy clipping to work, we need to populate the clip
 282     * distance varying slots whenever clipping is enabled, even if the vertex
 283     * shader doesn't write to gl_ClipDistance.
 284     */
 285    if (c.key.base.userclip_active) {
 286       outputs_written |= BITFIELD64_BIT(VARYING_SLOT_CLIP_DIST0);
 287       outputs_written |= BITFIELD64_BIT(VARYING_SLOT_CLIP_DIST1);
 288    }
 289
 290    brw_compute_vue_map(brw, &prog_data.base.vue_map, outputs_written);
 291
 292    if (0) {
 293       _mesa_fprint_program_opt(stderr, &c.vp->program.Base, PROG_PRINT_DEBUG,
 294                                true);
 295    }
 296
 297    /* Emit GEN4 code.
 298     */
 299    program = brw_vs_emit(brw, prog, &c, &prog_data, mem_ctx, &program_size);
 300    if (program == NULL) {
 301       ralloc_free(mem_ctx);
 302       return false;
 303    }
 304
 305    /* Scratch space is used for register spilling */
 306    if (c.base.last_scratch) {
 307       perf_debug("Vertex shader triggered register spilling.  "
 308                  "Try reducing the number of live vec4 values to "
 309                  "improve performance.\n");
 310
 311       prog_data.base.base.total_scratch
 312          = brw_get_scratch_size(c.base.last_scratch*REG_SIZE);
 313
 314       brw_get_scratch_bo(brw, &brw->vs.base.scratch_bo,
 315                          prog_data.base.base.total_scratch *
 316                          brw->max_vs_threads);
 317    }
 318
 319    brw_upload_cache(&brw->cache, BRW_CACHE_VS_PROG,
 320                     &c.key, sizeof(c.key),
 321                     program, program_size,
 322                     &prog_data, sizeof(prog_data),
 323                     &brw->vs.base.prog_offset, &brw->vs.prog_data);
 324    ralloc_free(mem_ctx);
 325
 326    return true;
 327 }
 328
 329 static bool
 330 key_debug(struct brw_context *brw, const char *name, int a, int b)
 331 {
 332    if (a != b) {
 333       perf_debug("  %s %d->%d\n", name, a, b);
 334       return true;
 335    }
 336    return false;
 337 }
 338
 339 void
 340 brw_vs_debug_recompile(struct brw_context *brw,
 341                        struct gl_shader_program *prog,
 342                        const struct brw_vs_prog_key *key)
 343 {
 344    struct brw_cache_item *c = NULL;
 345    const struct brw_vs_prog_key *old_key = NULL;
 346    bool found = false;
 347
 348    perf_debug("Recompiling vertex shader for program %d\n", prog->Name);
 349
 350    for (unsigned int i = 0; i < brw->cache.size; i++) {
 351       for (c = brw->cache.items[i]; c; c = c->next) {
 352          if (c->cache_id == BRW_CACHE_VS_PROG) {
 353             old_key = c->key;
 354
 355             if (old_key->base.program_string_id == key->base.program_string_id)
 356                break;
 357          }
 358       }
 359       if (c)
 360          break;
 361    }
 362
 363    if (!c) {
 364       perf_debug("  Didn't find previous compile in the shader cache for "
 365                  "debug\n");
 366       return;
 367    }
 368
 369    for (unsigned int i = 0; i < VERT_ATTRIB_MAX; i++) {
 370       found |= key_debug(brw, "Vertex attrib w/a flags",
 371                          old_key->gl_attrib_wa_flags[i],
 372                          key->gl_attrib_wa_flags[i]);
 373    }
 374
 375    found |= key_debug(brw, "user clip flags",
 376                       old_key->base.userclip_active, key->base.userclip_active);
 377
 378    found |= key_debug(brw, "user clipping planes as push constants",
 379                       old_key->base.nr_userclip_plane_consts,
 380                       key->base.nr_userclip_plane_consts);
 381
 382    found |= key_debug(brw, "copy edgeflag",
 383                       old_key->copy_edgeflag, key->copy_edgeflag);
 384    found |= key_debug(brw, "PointCoord replace",
 385                       old_key->point_coord_replace, key->point_coord_replace);
 386    found |= key_debug(brw, "vertex color clamping",
 387                       old_key->clamp_vertex_color, key->clamp_vertex_color);
 388
 389    found |= brw_debug_recompile_sampler_key(brw, &old_key->base.tex,
 390                                             &key->base.tex);
 391
 392    if (!found) {
 393       perf_debug("  Something else\n");
 394    }
 395 }
 396
 397
 398 void
 399 brw_setup_vec4_key_clip_info(struct brw_context *brw,
 400                              struct brw_vec4_prog_key *key,
 401                              bool program_uses_clip_distance)
 402 {
 403    struct gl_context *ctx = &brw->ctx;
 404
 405    key->userclip_active = (ctx->Transform.ClipPlanesEnabled != 0);
 406    if (key->userclip_active && !program_uses_clip_distance) {
 407       key->nr_userclip_plane_consts
 408          = _mesa_logbase2(ctx->Transform.ClipPlanesEnabled) + 1;
 409    }
 410 }
 411
 412
 413 static void brw_upload_vs_prog(struct brw_context *brw)
 414 {
 415    struct gl_context *ctx = &brw->ctx;
 416    struct brw_vs_prog_key key;
 417    /* BRW_NEW_VERTEX_PROGRAM */
 418    struct brw_vertex_program *vp =
 419       (struct brw_vertex_program *)brw->vertex_program;
 420    struct gl_program *prog = (struct gl_program *) brw->vertex_program;
 421    int i;
 422
 423    memset(&key, 0, sizeof(key));
 424
 425    /* Just upload the program verbatim for now.  Always send it all
 426     * the inputs it asks for, whether they are varying or not.
 427     */
 428    key.base.program_string_id = vp->id;
 429    brw_setup_vec4_key_clip_info(brw, &key.base,
 430                                 vp->program.Base.UsesClipDistanceOut);
 431
 432    /* _NEW_POLYGON */
 433    if (brw->gen < 6) {
 434       key.copy_edgeflag = (ctx->Polygon.FrontMode != GL_FILL ||
 435                            ctx->Polygon.BackMode != GL_FILL);
 436    }
 437
 438    if (prog->OutputsWritten & (VARYING_BIT_COL0 | VARYING_BIT_COL1 |
 439                                VARYING_BIT_BFC0 | VARYING_BIT_BFC1)) {
 440       /* _NEW_LIGHT | _NEW_BUFFERS */
 441       key.clamp_vertex_color = ctx->Light._ClampVertexColor;
 442    }
 443
 444    /* _NEW_POINT */
 445    if (brw->gen < 6 && ctx->Point.PointSprite) {
 446       for (i = 0; i < 8; i++) {
 447          if (ctx->Point.CoordReplace[i])
 448             key.point_coord_replace |= (1 << i);
 449       }
 450    }
 451
 452    /* _NEW_TEXTURE */
 453    brw_populate_sampler_prog_key_data(ctx, prog, brw->vs.base.sampler_count,
 454                                       &key.base.tex);
 455
 456    /* BRW_NEW_VERTICES */
 457    if (brw->gen < 8 && !brw->is_haswell) {
 458       /* Prior to Haswell, the hardware can't natively support GL_FIXED or
 459        * 2_10_10_10_REV vertex formats.  Set appropriate workaround flags.
 460        */
 461       for (i = 0; i < VERT_ATTRIB_MAX; i++) {
 462          if (!(vp->program.Base.InputsRead & BITFIELD64_BIT(i)))
 463             continue;
 464
 465          uint8_t wa_flags = 0;
 466
 467          switch (brw->vb.inputs[i].glarray->Type) {
 468
 469          case GL_FIXED:
 470             wa_flags = brw->vb.inputs[i].glarray->Size;
 471             break;
 472
 473          case GL_INT_2_10_10_10_REV:
 474             wa_flags |= BRW_ATTRIB_WA_SIGN;
 475             /* fallthough */
 476
 477          case GL_UNSIGNED_INT_2_10_10_10_REV:
 478             if (brw->vb.inputs[i].glarray->Format == GL_BGRA)
 479                wa_flags |= BRW_ATTRIB_WA_BGRA;
 480
 481             if (brw->vb.inputs[i].glarray->Normalized)
 482                wa_flags |= BRW_ATTRIB_WA_NORMALIZE;
 483             else if (!brw->vb.inputs[i].glarray->Integer)
 484                wa_flags |= BRW_ATTRIB_WA_SCALE;
 485
 486             break;
 487          }
 488
 489          key.gl_attrib_wa_flags[i] = wa_flags;
 490       }
 491    }
 492
 493    if (!brw_search_cache(&brw->cache, BRW_CACHE_VS_PROG,
 494                          &key, sizeof(key),
 495                          &brw->vs.base.prog_offset, &brw->vs.prog_data)) {
 496       bool success =
 497          do_vs_prog(brw, ctx->_Shader->CurrentProgram[MESA_SHADER_VERTEX], vp,
 498                     &key);
 499       (void) success;
 500       assert(success);
 501    }
 502    brw->vs.base.prog_data = &brw->vs.prog_data->base.base;
 503
 504    if (memcmp(&brw->vs.prog_data->base.vue_map, &brw->vue_map_geom_out,
 505               sizeof(brw->vue_map_geom_out)) != 0) {
 506       brw->vue_map_vs = brw->vs.prog_data->base.vue_map;
 507       brw->state.dirty.brw |= BRW_NEW_VUE_MAP_VS;
 508       if (brw->gen < 6) {
 509          /* No geometry shader support, so the VS VUE map is the VUE map for
 510           * the output of the "geometry" portion of the pipeline.
 511           */
 512          brw->vue_map_geom_out = brw->vue_map_vs;
 513          brw->state.dirty.brw |= BRW_NEW_VUE_MAP_GEOM_OUT;
 514       }
 515    }
 516 }
 517
 518 /* See brw_vs.c:
 519  */
 520 const struct brw_tracked_state brw_vs_prog = {
 521    .dirty = {
 522       .mesa  = _NEW_BUFFERS |
 523                _NEW_LIGHT |
 524                _NEW_POINT |
 525                _NEW_POLYGON |
 526                _NEW_TEXTURE |
 527                _NEW_TRANSFORM,
 528       .brw   = BRW_NEW_VERTEX_PROGRAM |
 529                BRW_NEW_VERTICES,
 530    },
 531    .emit = brw_upload_vs_prog
 532 };
 533
 534 bool
 535 brw_vs_precompile(struct gl_context *ctx,
 536                   struct gl_shader_program *shader_prog,
 537                   struct gl_program *prog)
 538 {
 539    struct brw_context *brw = brw_context(ctx);
 540    struct brw_vs_prog_key key;
 541    uint32_t old_prog_offset = brw->vs.base.prog_offset;
 542    struct brw_vs_prog_data *old_prog_data = brw->vs.prog_data;
 543    bool success;
 544
 545    struct gl_vertex_program *vp = (struct gl_vertex_program *) prog;
 546    struct brw_vertex_program *bvp = brw_vertex_program(vp);
 547
 548    memset(&key, 0, sizeof(key));
 549
 550    brw_vec4_setup_prog_key_for_precompile(ctx, &key.base, bvp->id, &vp->Base);
 551    key.clamp_vertex_color =
 552       (prog->OutputsWritten & (VARYING_BIT_COL0 | VARYING_BIT_COL1 |
 553                                VARYING_BIT_BFC0 | VARYING_BIT_BFC1));
 554
 555    success = do_vs_prog(brw, shader_prog, bvp, &key);
 556
 557    brw->vs.base.prog_offset = old_prog_offset;
 558    brw->vs.prog_data = old_prog_data;
 559
 560    return success;
 561 }