src/gallium/auxiliary/gallivm/lp_bld_sample_soa.c

   1 /**************************************************************************
   2  *
   3  * Copyright 2009 VMware, Inc.
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  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.
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  19  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  20  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
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  27
  28 /**
  29  * @file
  30  * Texture sampling -- SoA.
  31  *
  32  * @author Jose Fonseca <jfonseca@vmware.com>
  33  * @author Brian Paul <brianp@vmware.com>
  34  */
  35
  36 #include "pipe/p_defines.h"
  37 #include "pipe/p_state.h"
  38 #include "util/u_debug.h"
  39 #include "util/u_dump.h"
  40 #include "util/u_memory.h"
  41 #include "util/u_math.h"
  42 #include "util/u_format.h"
  43 #include "lp_bld_debug.h"
  44 #include "lp_bld_type.h"
  45 #include "lp_bld_const.h"
  46 #include "lp_bld_conv.h"
  47 #include "lp_bld_arit.h"
  48 #include "lp_bld_bitarit.h"
  49 #include "lp_bld_logic.h"
  50 #include "lp_bld_printf.h"
  51 #include "lp_bld_swizzle.h"
  52 #include "lp_bld_flow.h"
  53 #include "lp_bld_gather.h"
  54 #include "lp_bld_format.h"
  55 #include "lp_bld_sample.h"
  56 #include "lp_bld_sample_aos.h"
  57 #include "lp_bld_struct.h"
  58 #include "lp_bld_quad.h"
  59
  60
  61 /**
  62  * Generate code to fetch a texel from a texture at int coords (x, y, z).
  63  * The computation depends on whether the texture is 1D, 2D or 3D.
  64  * The result, texel, will be float vectors:
  65  *   texel[0] = red values
  66  *   texel[1] = green values
  67  *   texel[2] = blue values
  68  *   texel[3] = alpha values
  69  */
  70 static void
  71 lp_build_sample_texel_soa(struct lp_build_sample_context *bld,
  72                           unsigned unit,
  73                           LLVMValueRef width,
  74                           LLVMValueRef height,
  75                           LLVMValueRef depth,
  76                           LLVMValueRef x,
  77                           LLVMValueRef y,
  78                           LLVMValueRef z,
  79                           LLVMValueRef y_stride,
  80                           LLVMValueRef z_stride,
  81                           LLVMValueRef data_ptr,
  82                           LLVMValueRef texel_out[4])
  83 {
  84    const struct lp_sampler_static_state *static_state = bld->static_state;
  85    const unsigned dims = bld->dims;
  86    struct lp_build_context *int_coord_bld = &bld->int_coord_bld;
  87    LLVMBuilderRef builder = bld->gallivm->builder;
  88    LLVMValueRef offset;
  89    LLVMValueRef i, j;
  90    LLVMValueRef use_border = NULL;
  91
  92    /* use_border = x < 0 || x >= width || y < 0 || y >= height */
  93    if (lp_sampler_wrap_mode_uses_border_color(static_state->wrap_s,
  94                                               static_state->min_img_filter,
  95                                               static_state->mag_img_filter)) {
  96       LLVMValueRef b1, b2;
  97       b1 = lp_build_cmp(int_coord_bld, PIPE_FUNC_LESS, x, int_coord_bld->zero);
  98       b2 = lp_build_cmp(int_coord_bld, PIPE_FUNC_GEQUAL, x, width);
  99       use_border = LLVMBuildOr(builder, b1, b2, "b1_or_b2");
 100    }
 101
 102    if (dims >= 2 &&
 103        lp_sampler_wrap_mode_uses_border_color(static_state->wrap_t,
 104                                               static_state->min_img_filter,
 105                                               static_state->mag_img_filter)) {
 106       LLVMValueRef b1, b2;
 107       b1 = lp_build_cmp(int_coord_bld, PIPE_FUNC_LESS, y, int_coord_bld->zero);
 108       b2 = lp_build_cmp(int_coord_bld, PIPE_FUNC_GEQUAL, y, height);
 109       if (use_border) {
 110          use_border = LLVMBuildOr(builder, use_border, b1, "ub_or_b1");
 111          use_border = LLVMBuildOr(builder, use_border, b2, "ub_or_b2");
 112       }
 113       else {
 114          use_border = LLVMBuildOr(builder, b1, b2, "b1_or_b2");
 115       }
 116    }
 117
 118    if (dims == 3 &&
 119        lp_sampler_wrap_mode_uses_border_color(static_state->wrap_r,
 120                                               static_state->min_img_filter,
 121                                               static_state->mag_img_filter)) {
 122       LLVMValueRef b1, b2;
 123       b1 = lp_build_cmp(int_coord_bld, PIPE_FUNC_LESS, z, int_coord_bld->zero);
 124       b2 = lp_build_cmp(int_coord_bld, PIPE_FUNC_GEQUAL, z, depth);
 125       if (use_border) {
 126          use_border = LLVMBuildOr(builder, use_border, b1, "ub_or_b1");
 127          use_border = LLVMBuildOr(builder, use_border, b2, "ub_or_b2");
 128       }
 129       else {
 130          use_border = LLVMBuildOr(builder, b1, b2, "b1_or_b2");
 131       }
 132    }
 133
 134    /* convert x,y,z coords to linear offset from start of texture, in bytes */
 135    lp_build_sample_offset(&bld->int_coord_bld,
 136                           bld->format_desc,
 137                           x, y, z, y_stride, z_stride,
 138                           &offset, &i, &j);
 139
 140    if (use_border) {
 141       /* If we can sample the border color, it means that texcoords may
 142        * lie outside the bounds of the texture image.  We need to do
 143        * something to prevent reading out of bounds and causing a segfault.
 144        *
 145        * Simply AND the texture coords with !use_border.  This will cause
 146        * coords which are out of bounds to become zero.  Zero's guaranteed
 147        * to be inside the texture image.
 148        */
 149       offset = lp_build_andnot(&bld->int_coord_bld, offset, use_border);
 150    }
 151
 152    lp_build_fetch_rgba_soa(bld->gallivm,
 153                            bld->format_desc,
 154                            bld->texel_type,
 155                            data_ptr, offset,
 156                            i, j,
 157                            texel_out);
 158
 159    /*
 160     * Note: if we find an app which frequently samples the texture border
 161     * we might want to implement a true conditional here to avoid sampling
 162     * the texture whenever possible (since that's quite a bit of code).
 163     * Ex:
 164     *   if (use_border) {
 165     *      texel = border_color;
 166     *   }
 167     *   else {
 168     *      texel = sample_texture(coord);
 169     *   }
 170     * As it is now, we always sample the texture, then selectively replace
 171     * the texel color results with the border color.
 172     */
 173
 174    if (use_border) {
 175       /* select texel color or border color depending on use_border */
 176       LLVMValueRef border_color_ptr =
 177          bld->dynamic_state->border_color(bld->dynamic_state,
 178                                           bld->gallivm, unit);
 179       int chan;
 180       for (chan = 0; chan < 4; chan++) {
 181          LLVMValueRef border_chan =
 182             lp_build_array_get(bld->gallivm, border_color_ptr,
 183                                lp_build_const_int32(bld->gallivm, chan));
 184          LLVMValueRef border_chan_vec =
 185             lp_build_broadcast_scalar(&bld->float_vec_bld, border_chan);
 186          texel_out[chan] = lp_build_select(&bld->texel_bld, use_border,
 187                                            border_chan_vec, texel_out[chan]);
 188       }
 189    }
 190 }
 191
 192
 193 /**
 194  * Helper to compute the mirror function for the PIPE_WRAP_MIRROR modes.
 195  */
 196 static LLVMValueRef
 197 lp_build_coord_mirror(struct lp_build_sample_context *bld,
 198                       LLVMValueRef coord)
 199 {
 200    struct lp_build_context *coord_bld = &bld->coord_bld;
 201    struct lp_build_context *int_coord_bld = &bld->int_coord_bld;
 202    LLVMValueRef fract, flr, isOdd;
 203
 204    lp_build_ifloor_fract(coord_bld, coord, &flr, &fract);
 205
 206    /* isOdd = flr & 1 */
 207    isOdd = LLVMBuildAnd(bld->gallivm->builder, flr, int_coord_bld->one, "");
 208
 209    /* make coord positive or negative depending on isOdd */
 210    coord = lp_build_set_sign(coord_bld, fract, isOdd);
 211
 212    /* convert isOdd to float */
 213    isOdd = lp_build_int_to_float(coord_bld, isOdd);
 214
 215    /* add isOdd to coord */
 216    coord = lp_build_add(coord_bld, coord, isOdd);
 217
 218    return coord;
 219 }
 220
 221
 222 /**
 223  * Build LLVM code for texture wrap mode for linear filtering.
 224  * \param x0_out  returns first integer texcoord
 225  * \param x1_out  returns second integer texcoord
 226  * \param weight_out  returns linear interpolation weight
 227  */
 228 static void
 229 lp_build_sample_wrap_linear(struct lp_build_sample_context *bld,
 230                             LLVMValueRef coord,
 231                             LLVMValueRef length,
 232                             LLVMValueRef length_f,
 233                             boolean is_pot,
 234                             unsigned wrap_mode,
 235                             LLVMValueRef *x0_out,
 236                             LLVMValueRef *x1_out,
 237                             LLVMValueRef *weight_out)
 238 {
 239    struct lp_build_context *coord_bld = &bld->coord_bld;
 240    struct lp_build_context *int_coord_bld = &bld->int_coord_bld;
 241    LLVMBuilderRef builder = bld->gallivm->builder;
 242    LLVMValueRef half = lp_build_const_vec(bld->gallivm, coord_bld->type, 0.5);
 243    LLVMValueRef length_minus_one = lp_build_sub(int_coord_bld, length, int_coord_bld->one);
 244    LLVMValueRef coord0, coord1, weight;
 245
 246    switch(wrap_mode) {
 247    case PIPE_TEX_WRAP_REPEAT:
 248       /* mul by size and subtract 0.5 */
 249       coord = lp_build_mul(coord_bld, coord, length_f);
 250       coord = lp_build_sub(coord_bld, coord, half);
 251       /* convert to int, compute lerp weight */
 252       lp_build_ifloor_fract(coord_bld, coord, &coord0, &weight);
 253       /* repeat wrap */
 254       if (is_pot) {
 255          coord1 = lp_build_add(int_coord_bld, coord0, int_coord_bld->one);
 256          coord0 = LLVMBuildAnd(builder, coord0, length_minus_one, "");
 257          coord1 = LLVMBuildAnd(builder, coord1, length_minus_one, "");
 258       }
 259       else {
 260          /* Add a bias to the texcoord to handle negative coords */
 261          LLVMValueRef bias = lp_build_mul_imm(int_coord_bld, length, 1024);
 262          LLVMValueRef mask;
 263          coord0 = LLVMBuildAdd(builder, coord0, bias, "");
 264          coord0 = LLVMBuildURem(builder, coord0, length, "");
 265          mask = lp_build_compare(bld->gallivm, int_coord_bld->type,
 266                                  PIPE_FUNC_NOTEQUAL, coord0, length_minus_one);
 267          coord1 = LLVMBuildAnd(builder,
 268                               lp_build_add(int_coord_bld, coord0, int_coord_bld->one),
 269                               mask, "");
 270       }
 271       break;
 272
 273    case PIPE_TEX_WRAP_CLAMP:
 274       if (bld->static_state->normalized_coords) {
 275          /* scale coord to length */
 276          coord = lp_build_mul(coord_bld, coord, length_f);
 277       }
 278
 279       /* clamp to [0, length] */
 280       coord = lp_build_clamp(coord_bld, coord, coord_bld->zero, length_f);
 281
 282       coord = lp_build_sub(coord_bld, coord, half);
 283
 284       /* convert to int, compute lerp weight */
 285       lp_build_ifloor_fract(coord_bld, coord, &coord0, &weight);
 286       coord1 = lp_build_add(int_coord_bld, coord0, int_coord_bld->one);
 287       break;
 288
 289    case PIPE_TEX_WRAP_CLAMP_TO_EDGE:
 290       {
 291          struct lp_build_context abs_coord_bld = bld->coord_bld;
 292          abs_coord_bld.type.sign = FALSE;
 293
 294          if (bld->static_state->normalized_coords) {
 295             /* mul by tex size */
 296             coord = lp_build_mul(coord_bld, coord, length_f);
 297          }
 298          /* clamp to length max */
 299          coord = lp_build_min(coord_bld, coord, length_f);
 300          /* subtract 0.5 */
 301          coord = lp_build_sub(coord_bld, coord, half);
 302          /* clamp to [0, length - 0.5] */
 303          coord = lp_build_max(coord_bld, coord, coord_bld->zero);
 304          /* convert to int, compute lerp weight */
 305          lp_build_ifloor_fract(&abs_coord_bld, coord, &coord0, &weight);
 306          coord1 = lp_build_add(int_coord_bld, coord0, int_coord_bld->one);
 307          /* coord1 = min(coord1, length-1) */
 308          coord1 = lp_build_min(int_coord_bld, coord1, length_minus_one);
 309          break;
 310       }
 311
 312    case PIPE_TEX_WRAP_CLAMP_TO_BORDER:
 313       {
 314          LLVMValueRef min;
 315          if (bld->static_state->normalized_coords) {
 316             /* scale coord to length */
 317             coord = lp_build_mul(coord_bld, coord, length_f);
 318          }
 319          /* was: clamp to [-0.5, length + 0.5], then sub 0.5 */
 320          coord = lp_build_sub(coord_bld, coord, half);
 321          min = lp_build_const_vec(bld->gallivm, coord_bld->type, -1.0F);
 322          coord = lp_build_clamp(coord_bld, coord, min, length_f);
 323          /* convert to int, compute lerp weight */
 324          lp_build_ifloor_fract(coord_bld, coord, &coord0, &weight);
 325          coord1 = lp_build_add(int_coord_bld, coord0, int_coord_bld->one);
 326       }
 327       break;
 328
 329    case PIPE_TEX_WRAP_MIRROR_REPEAT:
 330       /* compute mirror function */
 331       coord = lp_build_coord_mirror(bld, coord);
 332
 333       /* scale coord to length */
 334       coord = lp_build_mul(coord_bld, coord, length_f);
 335       coord = lp_build_sub(coord_bld, coord, half);
 336
 337       /* convert to int, compute lerp weight */
 338       lp_build_ifloor_fract(coord_bld, coord, &coord0, &weight);
 339       coord1 = lp_build_add(int_coord_bld, coord0, int_coord_bld->one);
 340
 341       /* coord0 = max(coord0, 0) */
 342       coord0 = lp_build_max(int_coord_bld, coord0, int_coord_bld->zero);
 343       /* coord1 = min(coord1, length-1) */
 344       coord1 = lp_build_min(int_coord_bld, coord1, length_minus_one);
 345       break;
 346
 347    case PIPE_TEX_WRAP_MIRROR_CLAMP:
 348       coord = lp_build_abs(coord_bld, coord);
 349
 350       if (bld->static_state->normalized_coords) {
 351          /* scale coord to length */
 352          coord = lp_build_mul(coord_bld, coord, length_f);
 353       }
 354
 355       /* clamp to [0, length] */
 356       coord = lp_build_min(coord_bld, coord, length_f);
 357
 358       coord = lp_build_sub(coord_bld, coord, half);
 359
 360       /* convert to int, compute lerp weight */
 361       lp_build_ifloor_fract(coord_bld, coord, &coord0, &weight);
 362       coord1 = lp_build_add(int_coord_bld, coord0, int_coord_bld->one);
 363       break;
 364
 365    case PIPE_TEX_WRAP_MIRROR_CLAMP_TO_EDGE:
 366       {
 367          LLVMValueRef min, max;
 368          struct lp_build_context abs_coord_bld = bld->coord_bld;
 369          abs_coord_bld.type.sign = FALSE;
 370          coord = lp_build_abs(coord_bld, coord);
 371
 372          if (bld->static_state->normalized_coords) {
 373             /* scale coord to length */
 374             coord = lp_build_mul(coord_bld, coord, length_f);
 375          }
 376
 377          /* clamp to [0.5, length - 0.5] */
 378          min = half;
 379          max = lp_build_sub(coord_bld, length_f, min);
 380          coord = lp_build_clamp(coord_bld, coord, min, max);
 381
 382          coord = lp_build_sub(coord_bld, coord, half);
 383
 384          /* convert to int, compute lerp weight */
 385          lp_build_ifloor_fract(&abs_coord_bld, coord, &coord0, &weight);
 386          coord1 = lp_build_add(int_coord_bld, coord0, int_coord_bld->one);
 387       }
 388       break;
 389
 390    case PIPE_TEX_WRAP_MIRROR_CLAMP_TO_BORDER:
 391       {
 392          coord = lp_build_abs(coord_bld, coord);
 393
 394          if (bld->static_state->normalized_coords) {
 395             /* scale coord to length */
 396             coord = lp_build_mul(coord_bld, coord, length_f);
 397          }
 398
 399          /* was: clamp to [-0.5, length + 0.5] then sub 0.5 */
 400          /* skip -0.5 clamp (always positive), do sub first */
 401          coord = lp_build_sub(coord_bld, coord, half);
 402          coord = lp_build_min(coord_bld, coord, length_f);
 403
 404          /* convert to int, compute lerp weight */
 405          lp_build_ifloor_fract(coord_bld, coord, &coord0, &weight);
 406          coord1 = lp_build_add(int_coord_bld, coord0, int_coord_bld->one);
 407       }
 408       break;
 409
 410    default:
 411       assert(0);
 412       coord0 = NULL;
 413       coord1 = NULL;
 414       weight = NULL;
 415    }
 416
 417    *x0_out = coord0;
 418    *x1_out = coord1;
 419    *weight_out = weight;
 420 }
 421
 422
 423 /**
 424  * Build LLVM code for texture wrap mode for nearest filtering.
 425  * \param coord  the incoming texcoord (nominally in [0,1])
 426  * \param length  the texture size along one dimension, as int vector
 427  * \param is_pot  if TRUE, length is a power of two
 428  * \param wrap_mode  one of PIPE_TEX_WRAP_x
 429  */
 430 static LLVMValueRef
 431 lp_build_sample_wrap_nearest(struct lp_build_sample_context *bld,
 432                              LLVMValueRef coord,
 433                              LLVMValueRef length,
 434                              LLVMValueRef length_f,
 435                              boolean is_pot,
 436                              unsigned wrap_mode)
 437 {
 438    struct lp_build_context *coord_bld = &bld->coord_bld;
 439    struct lp_build_context *int_coord_bld = &bld->int_coord_bld;
 440    LLVMBuilderRef builder = bld->gallivm->builder;
 441    LLVMValueRef length_minus_one = lp_build_sub(int_coord_bld, length, int_coord_bld->one);
 442    LLVMValueRef icoord;
 443
 444    switch(wrap_mode) {
 445    case PIPE_TEX_WRAP_REPEAT:
 446       coord = lp_build_mul(coord_bld, coord, length_f);
 447       icoord = lp_build_ifloor(coord_bld, coord);
 448       if (is_pot)
 449          icoord = LLVMBuildAnd(builder, icoord, length_minus_one, "");
 450       else {
 451          /* Add a bias to the texcoord to handle negative coords */
 452          LLVMValueRef bias = lp_build_mul_imm(int_coord_bld, length, 1024);
 453          icoord = LLVMBuildAdd(builder, icoord, bias, "");
 454          icoord = LLVMBuildURem(builder, icoord, length, "");
 455       }
 456       break;
 457
 458    case PIPE_TEX_WRAP_CLAMP:
 459    case PIPE_TEX_WRAP_CLAMP_TO_EDGE:
 460       if (bld->static_state->normalized_coords) {
 461          /* scale coord to length */
 462          coord = lp_build_mul(coord_bld, coord, length_f);
 463       }
 464
 465       /* floor */
 466       /* use itrunc instead since we clamp to 0 anyway */
 467       icoord = lp_build_itrunc(coord_bld, coord);
 468
 469       /* clamp to [0, length - 1]. */
 470       icoord = lp_build_clamp(int_coord_bld, icoord, int_coord_bld->zero,
 471                               length_minus_one);
 472       break;
 473
 474    case PIPE_TEX_WRAP_CLAMP_TO_BORDER:
 475       /* Note: this is the same as CLAMP_TO_EDGE, except min = -min */
 476       {
 477          LLVMValueRef min, max;
 478
 479          if (bld->static_state->normalized_coords) {
 480             /* scale coord to length */
 481             coord = lp_build_mul(coord_bld, coord, length_f);
 482          }
 483
 484          icoord = lp_build_ifloor(coord_bld, coord);
 485
 486          /* clamp to [-1, length] */
 487          min = lp_build_negate(int_coord_bld, int_coord_bld->one);
 488          max = length;
 489          icoord = lp_build_clamp(int_coord_bld, icoord, min, max);
 490       }
 491       break;
 492
 493    case PIPE_TEX_WRAP_MIRROR_REPEAT:
 494       /* compute mirror function */
 495       coord = lp_build_coord_mirror(bld, coord);
 496
 497       /* scale coord to length */
 498       assert(bld->static_state->normalized_coords);
 499       coord = lp_build_mul(coord_bld, coord, length_f);
 500
 501       /* itrunc == ifloor here */
 502       icoord = lp_build_itrunc(coord_bld, coord);
 503
 504       /* clamp to [0, length - 1] */
 505       icoord = lp_build_min(int_coord_bld, icoord, length_minus_one);
 506       break;
 507
 508    case PIPE_TEX_WRAP_MIRROR_CLAMP:
 509    case PIPE_TEX_WRAP_MIRROR_CLAMP_TO_EDGE:
 510       coord = lp_build_abs(coord_bld, coord);
 511
 512       if (bld->static_state->normalized_coords) {
 513          /* scale coord to length */
 514          coord = lp_build_mul(coord_bld, coord, length_f);
 515       }
 516
 517       /* itrunc == ifloor here */
 518       icoord = lp_build_itrunc(coord_bld, coord);
 519
 520       /* clamp to [0, length - 1] */
 521       icoord = lp_build_min(int_coord_bld, icoord, length_minus_one);
 522       break;
 523
 524    case PIPE_TEX_WRAP_MIRROR_CLAMP_TO_BORDER:
 525       coord = lp_build_abs(coord_bld, coord);
 526
 527       if (bld->static_state->normalized_coords) {
 528          /* scale coord to length */
 529          coord = lp_build_mul(coord_bld, coord, length_f);
 530       }
 531
 532       /* itrunc == ifloor here */
 533       icoord = lp_build_itrunc(coord_bld, coord);
 534
 535       /* clamp to [0, length] */
 536       icoord = lp_build_min(int_coord_bld, icoord, length);
 537       break;
 538
 539    default:
 540       assert(0);
 541       icoord = NULL;
 542    }
 543
 544    return icoord;
 545 }
 546
 547
 548 /**
 549  * Generate code to sample a mipmap level with nearest filtering.
 550  * If sampling a cube texture, r = cube face in [0,5].
 551  */
 552 static void
 553 lp_build_sample_image_nearest(struct lp_build_sample_context *bld,
 554                               unsigned unit,
 555                               LLVMValueRef size,
 556                               LLVMValueRef row_stride_vec,
 557                               LLVMValueRef img_stride_vec,
 558                               LLVMValueRef data_ptr,
 559                               LLVMValueRef s,
 560                               LLVMValueRef t,
 561                               LLVMValueRef r,
 562                               LLVMValueRef colors_out[4])
 563 {
 564    const unsigned dims = bld->dims;
 565    LLVMValueRef width_vec;
 566    LLVMValueRef height_vec;
 567    LLVMValueRef depth_vec;
 568    LLVMValueRef flt_size;
 569    LLVMValueRef flt_width_vec;
 570    LLVMValueRef flt_height_vec;
 571    LLVMValueRef flt_depth_vec;
 572    LLVMValueRef x, y, z;
 573
 574    lp_build_extract_image_sizes(bld,
 575                                 bld->int_size_type,
 576                                 bld->int_coord_type,
 577                                 size,
 578                                 &width_vec, &height_vec, &depth_vec);
 579
 580    flt_size = lp_build_int_to_float(&bld->float_size_bld, size);
 581
 582    lp_build_extract_image_sizes(bld,
 583                                 bld->float_size_type,
 584                                 bld->coord_type,
 585                                 flt_size,
 586                                 &flt_width_vec, &flt_height_vec, &flt_depth_vec);
 587
 588    /*
 589     * Compute integer texcoords.
 590     */
 591    x = lp_build_sample_wrap_nearest(bld, s, width_vec, flt_width_vec,
 592                                     bld->static_state->pot_width,
 593                                     bld->static_state->wrap_s);
 594    lp_build_name(x, "tex.x.wrapped");
 595
 596    if (dims >= 2) {
 597       y = lp_build_sample_wrap_nearest(bld, t, height_vec, flt_height_vec,
 598                                        bld->static_state->pot_height,
 599                                        bld->static_state->wrap_t);
 600       lp_build_name(y, "tex.y.wrapped");
 601
 602       if (dims == 3) {
 603          z = lp_build_sample_wrap_nearest(bld, r, depth_vec, flt_depth_vec,
 604                                           bld->static_state->pot_depth,
 605                                           bld->static_state->wrap_r);
 606          lp_build_name(z, "tex.z.wrapped");
 607       }
 608       else if (bld->static_state->target == PIPE_TEXTURE_CUBE) {
 609          z = r;
 610       }
 611       else {
 612          z = NULL;
 613       }
 614    }
 615    else {
 616       y = z = NULL;
 617    }
 618
 619    /*
 620     * Get texture colors.
 621     */
 622    lp_build_sample_texel_soa(bld, unit,
 623                              width_vec, height_vec, depth_vec,
 624                              x, y, z,
 625                              row_stride_vec, img_stride_vec,
 626                              data_ptr, colors_out);
 627 }
 628
 629
 630 /**
 631  * Generate code to sample a mipmap level with linear filtering.
 632  * If sampling a cube texture, r = cube face in [0,5].
 633  */
 634 static void
 635 lp_build_sample_image_linear(struct lp_build_sample_context *bld,
 636                              unsigned unit,
 637                              LLVMValueRef size,
 638                              LLVMValueRef row_stride_vec,
 639                              LLVMValueRef img_stride_vec,
 640                              LLVMValueRef data_ptr,
 641                              LLVMValueRef s,
 642                              LLVMValueRef t,
 643                              LLVMValueRef r,
 644                              LLVMValueRef colors_out[4])
 645 {
 646    const unsigned dims = bld->dims;
 647    LLVMValueRef width_vec;
 648    LLVMValueRef height_vec;
 649    LLVMValueRef depth_vec;
 650    LLVMValueRef flt_size;
 651    LLVMValueRef flt_width_vec;
 652    LLVMValueRef flt_height_vec;
 653    LLVMValueRef flt_depth_vec;
 654    LLVMValueRef x0, y0, z0, x1, y1, z1;
 655    LLVMValueRef s_fpart, t_fpart, r_fpart;
 656    LLVMValueRef neighbors[2][2][4];
 657    int chan;
 658
 659    lp_build_extract_image_sizes(bld,
 660                                 bld->int_size_type,
 661                                 bld->int_coord_type,
 662                                 size,
 663                                 &width_vec, &height_vec, &depth_vec);
 664
 665    flt_size = lp_build_int_to_float(&bld->float_size_bld, size);
 666
 667    lp_build_extract_image_sizes(bld,
 668                                 bld->float_size_type,
 669                                 bld->coord_type,
 670                                 flt_size,
 671                                 &flt_width_vec, &flt_height_vec, &flt_depth_vec);
 672
 673    /*
 674     * Compute integer texcoords.
 675     */
 676    lp_build_sample_wrap_linear(bld, s, width_vec, flt_width_vec,
 677                                bld->static_state->pot_width,
 678                                bld->static_state->wrap_s,
 679                                &x0, &x1, &s_fpart);
 680    lp_build_name(x0, "tex.x0.wrapped");
 681    lp_build_name(x1, "tex.x1.wrapped");
 682
 683    if (dims >= 2) {
 684       lp_build_sample_wrap_linear(bld, t, height_vec, flt_height_vec,
 685                                   bld->static_state->pot_height,
 686                                   bld->static_state->wrap_t,
 687                                   &y0, &y1, &t_fpart);
 688       lp_build_name(y0, "tex.y0.wrapped");
 689       lp_build_name(y1, "tex.y1.wrapped");
 690
 691       if (dims == 3) {
 692          lp_build_sample_wrap_linear(bld, r, depth_vec, flt_depth_vec,
 693                                      bld->static_state->pot_depth,
 694                                      bld->static_state->wrap_r,
 695                                      &z0, &z1, &r_fpart);
 696          lp_build_name(z0, "tex.z0.wrapped");
 697          lp_build_name(z1, "tex.z1.wrapped");
 698       }
 699       else if (bld->static_state->target == PIPE_TEXTURE_CUBE) {
 700          z0 = z1 = r;  /* cube face */
 701          r_fpart = NULL;
 702       }
 703       else {
 704          z0 = z1 = NULL;
 705          r_fpart = NULL;
 706       }
 707    }
 708    else {
 709       y0 = y1 = t_fpart = NULL;
 710       z0 = z1 = r_fpart = NULL;
 711    }
 712
 713    /*
 714     * Get texture colors.
 715     */
 716    /* get x0/x1 texels */
 717    lp_build_sample_texel_soa(bld, unit,
 718                              width_vec, height_vec, depth_vec,
 719                              x0, y0, z0,
 720                              row_stride_vec, img_stride_vec,
 721                              data_ptr, neighbors[0][0]);
 722    lp_build_sample_texel_soa(bld, unit,
 723                              width_vec, height_vec, depth_vec,
 724                              x1, y0, z0,
 725                              row_stride_vec, img_stride_vec,
 726                              data_ptr, neighbors[0][1]);
 727
 728    if (dims == 1) {
 729       /* Interpolate two samples from 1D image to produce one color */
 730       for (chan = 0; chan < 4; chan++) {
 731          colors_out[chan] = lp_build_lerp(&bld->texel_bld, s_fpart,
 732                                           neighbors[0][0][chan],
 733                                           neighbors[0][1][chan]);
 734       }
 735    }
 736    else {
 737       /* 2D/3D texture */
 738       LLVMValueRef colors0[4];
 739
 740       /* get x0/x1 texels at y1 */
 741       lp_build_sample_texel_soa(bld, unit,
 742                                 width_vec, height_vec, depth_vec,
 743                                 x0, y1, z0,
 744                                 row_stride_vec, img_stride_vec,
 745                                 data_ptr, neighbors[1][0]);
 746       lp_build_sample_texel_soa(bld, unit,
 747                                 width_vec, height_vec, depth_vec,
 748                                 x1, y1, z0,
 749                                 row_stride_vec, img_stride_vec,
 750                                 data_ptr, neighbors[1][1]);
 751
 752       /* Bilinear interpolate the four samples from the 2D image / 3D slice */
 753       for (chan = 0; chan < 4; chan++) {
 754          colors0[chan] = lp_build_lerp_2d(&bld->texel_bld,
 755                                           s_fpart, t_fpart,
 756                                           neighbors[0][0][chan],
 757                                           neighbors[0][1][chan],
 758                                           neighbors[1][0][chan],
 759                                           neighbors[1][1][chan]);
 760       }
 761
 762       if (dims == 3) {
 763          LLVMValueRef neighbors1[2][2][4];
 764          LLVMValueRef colors1[4];
 765
 766          /* get x0/x1/y0/y1 texels at z1 */
 767          lp_build_sample_texel_soa(bld, unit,
 768                                    width_vec, height_vec, depth_vec,
 769                                    x0, y0, z1,
 770                                    row_stride_vec, img_stride_vec,
 771                                    data_ptr, neighbors1[0][0]);
 772          lp_build_sample_texel_soa(bld, unit,
 773                                    width_vec, height_vec, depth_vec,
 774                                    x1, y0, z1,
 775                                    row_stride_vec, img_stride_vec,
 776                                    data_ptr, neighbors1[0][1]);
 777          lp_build_sample_texel_soa(bld, unit,
 778                                    width_vec, height_vec, depth_vec,
 779                                    x0, y1, z1,
 780                                    row_stride_vec, img_stride_vec,
 781                                    data_ptr, neighbors1[1][0]);
 782          lp_build_sample_texel_soa(bld, unit,
 783                                    width_vec, height_vec, depth_vec,
 784                                    x1, y1, z1,
 785                                    row_stride_vec, img_stride_vec,
 786                                    data_ptr, neighbors1[1][1]);
 787
 788          /* Bilinear interpolate the four samples from the second Z slice */
 789          for (chan = 0; chan < 4; chan++) {
 790             colors1[chan] = lp_build_lerp_2d(&bld->texel_bld,
 791                                              s_fpart, t_fpart,
 792                                              neighbors1[0][0][chan],
 793                                              neighbors1[0][1][chan],
 794                                              neighbors1[1][0][chan],
 795                                              neighbors1[1][1][chan]);
 796          }
 797
 798          /* Linearly interpolate the two samples from the two 3D slices */
 799          for (chan = 0; chan < 4; chan++) {
 800             colors_out[chan] = lp_build_lerp(&bld->texel_bld,
 801                                              r_fpart,
 802                                              colors0[chan], colors1[chan]);
 803          }
 804       }
 805       else {
 806          /* 2D tex */
 807          for (chan = 0; chan < 4; chan++) {
 808             colors_out[chan] = colors0[chan];
 809          }
 810       }
 811    }
 812 }
 813
 814
 815 /**
 816  * Sample the texture/mipmap using given image filter and mip filter.
 817  * data0_ptr and data1_ptr point to the two mipmap levels to sample
 818  * from.  width0/1_vec, height0/1_vec, depth0/1_vec indicate their sizes.
 819  * If we're using nearest miplevel sampling the '1' values will be null/unused.
 820  */
 821 static void
 822 lp_build_sample_mipmap(struct lp_build_sample_context *bld,
 823                        unsigned unit,
 824                        unsigned img_filter,
 825                        unsigned mip_filter,
 826                        LLVMValueRef s,
 827                        LLVMValueRef t,
 828                        LLVMValueRef r,
 829                        LLVMValueRef ilevel0,
 830                        LLVMValueRef ilevel1,
 831                        LLVMValueRef lod_fpart,
 832                        LLVMValueRef *colors_out)
 833 {
 834    LLVMBuilderRef builder = bld->gallivm->builder;
 835    LLVMValueRef size0 = NULL;
 836    LLVMValueRef size1 = NULL;
 837    LLVMValueRef row_stride0_vec = NULL;
 838    LLVMValueRef row_stride1_vec = NULL;
 839    LLVMValueRef img_stride0_vec = NULL;
 840    LLVMValueRef img_stride1_vec = NULL;
 841    LLVMValueRef data_ptr0 = NULL;
 842    LLVMValueRef data_ptr1 = NULL;
 843    LLVMValueRef colors0[4], colors1[4];
 844    unsigned chan;
 845
 846    /* sample the first mipmap level */
 847    lp_build_mipmap_level_sizes(bld, ilevel0,
 848                                &size0,
 849                                &row_stride0_vec, &img_stride0_vec);
 850    data_ptr0 = lp_build_get_mipmap_level(bld, ilevel0);
 851    if (img_filter == PIPE_TEX_FILTER_NEAREST) {
 852       lp_build_sample_image_nearest(bld, unit,
 853                                     size0,
 854                                     row_stride0_vec, img_stride0_vec,
 855                                     data_ptr0, s, t, r,
 856                                     colors0);
 857    }
 858    else {
 859       assert(img_filter == PIPE_TEX_FILTER_LINEAR);
 860       lp_build_sample_image_linear(bld, unit,
 861                                    size0,
 862                                    row_stride0_vec, img_stride0_vec,
 863                                    data_ptr0, s, t, r,
 864                                    colors0);
 865    }
 866
 867    /* Store the first level's colors in the output variables */
 868    for (chan = 0; chan < 4; chan++) {
 869        LLVMBuildStore(builder, colors0[chan], colors_out[chan]);
 870    }
 871
 872    if (mip_filter == PIPE_TEX_MIPFILTER_LINEAR) {
 873       struct lp_build_if_state if_ctx;
 874       LLVMValueRef need_lerp;
 875
 876       /* need_lerp = lod_fpart > 0 */
 877       need_lerp = LLVMBuildFCmp(builder, LLVMRealUGT,
 878                                 lod_fpart,
 879                                 bld->float_bld.zero,
 880                                 "need_lerp");
 881
 882       lp_build_if(&if_ctx, bld->gallivm, need_lerp);
 883       {
 884          /* sample the second mipmap level */
 885          lp_build_mipmap_level_sizes(bld, ilevel1,
 886                                      &size1,
 887                                      &row_stride1_vec, &img_stride1_vec);
 888          data_ptr1 = lp_build_get_mipmap_level(bld, ilevel1);
 889          if (img_filter == PIPE_TEX_FILTER_NEAREST) {
 890             lp_build_sample_image_nearest(bld, unit,
 891                                           size1,
 892                                           row_stride1_vec, img_stride1_vec,
 893                                           data_ptr1, s, t, r,
 894                                           colors1);
 895          }
 896          else {
 897             lp_build_sample_image_linear(bld, unit,
 898                                          size1,
 899                                          row_stride1_vec, img_stride1_vec,
 900                                          data_ptr1, s, t, r,
 901                                          colors1);
 902          }
 903
 904          /* interpolate samples from the two mipmap levels */
 905
 906          lod_fpart = lp_build_broadcast_scalar(&bld->texel_bld, lod_fpart);
 907
 908          for (chan = 0; chan < 4; chan++) {
 909             colors0[chan] = lp_build_lerp(&bld->texel_bld, lod_fpart,
 910                                           colors0[chan], colors1[chan]);
 911             LLVMBuildStore(builder, colors0[chan], colors_out[chan]);
 912          }
 913       }
 914       lp_build_endif(&if_ctx);
 915    }
 916 }
 917
 918
 919
 920 /**
 921  * General texture sampling codegen.
 922  * This function handles texture sampling for all texture targets (1D,
 923  * 2D, 3D, cube) and all filtering modes.
 924  */
 925 static void
 926 lp_build_sample_general(struct lp_build_sample_context *bld,
 927                         unsigned unit,
 928                         LLVMValueRef s,
 929                         LLVMValueRef t,
 930                         LLVMValueRef r,
 931                         const LLVMValueRef *ddx,
 932                         const LLVMValueRef *ddy,
 933                         LLVMValueRef lod_bias, /* optional */
 934                         LLVMValueRef explicit_lod, /* optional */
 935                         LLVMValueRef *colors_out)
 936 {
 937    struct lp_build_context *int_bld = &bld->int_bld;
 938    LLVMBuilderRef builder = bld->gallivm->builder;
 939    const unsigned mip_filter = bld->static_state->min_mip_filter;
 940    const unsigned min_filter = bld->static_state->min_img_filter;
 941    const unsigned mag_filter = bld->static_state->mag_img_filter;
 942    LLVMValueRef lod_ipart = NULL, lod_fpart = NULL;
 943    LLVMValueRef ilevel0, ilevel1 = NULL;
 944    LLVMValueRef face_ddx[4], face_ddy[4];
 945    LLVMValueRef texels[4];
 946    LLVMValueRef first_level;
 947    LLVMValueRef i32t_zero = lp_build_const_int32(bld->gallivm, 0);
 948    unsigned chan;
 949
 950    /*
 951    printf("%s mip %d  min %d  mag %d\n", __FUNCTION__,
 952           mip_filter, min_filter, mag_filter);
 953    */
 954
 955    /*
 956     * Choose cube face, recompute texcoords and derivatives for the chosen face.
 957     */
 958    if (bld->static_state->target == PIPE_TEXTURE_CUBE) {
 959       LLVMValueRef face, face_s, face_t;
 960       lp_build_cube_lookup(bld, s, t, r, &face, &face_s, &face_t);
 961       s = face_s; /* vec */
 962       t = face_t; /* vec */
 963       /* use 'r' to indicate cube face */
 964       r = lp_build_broadcast_scalar(&bld->int_coord_bld, face); /* vec */
 965
 966       /* recompute ddx, ddy using the new (s,t) face texcoords */
 967       face_ddx[0] = lp_build_scalar_ddx(&bld->coord_bld, s);
 968       face_ddx[1] = lp_build_scalar_ddx(&bld->coord_bld, t);
 969       face_ddx[2] = NULL;
 970       face_ddx[3] = NULL;
 971       face_ddy[0] = lp_build_scalar_ddy(&bld->coord_bld, s);
 972       face_ddy[1] = lp_build_scalar_ddy(&bld->coord_bld, t);
 973       face_ddy[2] = NULL;
 974       face_ddy[3] = NULL;
 975       ddx = face_ddx;
 976       ddy = face_ddy;
 977    }
 978
 979    /*
 980     * Compute the level of detail (float).
 981     */
 982    if (min_filter != mag_filter ||
 983        mip_filter != PIPE_TEX_MIPFILTER_NONE) {
 984       /* Need to compute lod either to choose mipmap levels or to
 985        * distinguish between minification/magnification with one mipmap level.
 986        */
 987       lp_build_lod_selector(bld, unit, ddx, ddy,
 988                             lod_bias, explicit_lod,
 989                             mip_filter,
 990                             &lod_ipart, &lod_fpart);
 991    } else {
 992       lod_ipart = i32t_zero;
 993    }
 994
 995    /*
 996     * Compute integer mipmap level(s) to fetch texels from: ilevel0, ilevel1
 997     */
 998    switch (mip_filter) {
 999    default:
1000       assert(0 && "bad mip_filter value in lp_build_sample_soa()");
1001       /* fall-through */
1002    case PIPE_TEX_MIPFILTER_NONE:
1003       /* always use mip level 0 */
1004       if (bld->static_state->target == PIPE_TEXTURE_CUBE) {
1005          /* XXX this is a work-around for an apparent bug in LLVM 2.7.
1006           * We should be able to set ilevel0 = const(0) but that causes
1007           * bad x86 code to be emitted.
1008           */
1009          assert(lod_ipart);
1010          lp_build_nearest_mip_level(bld, unit, lod_ipart, &ilevel0);
1011       }
1012       else {
1013          first_level = bld->dynamic_state->first_level(bld->dynamic_state,
1014                                                        bld->gallivm, unit);
1015          ilevel0 = first_level;
1016       }
1017       break;
1018    case PIPE_TEX_MIPFILTER_NEAREST:
1019       assert(lod_ipart);
1020       lp_build_nearest_mip_level(bld, unit, lod_ipart, &ilevel0);
1021       break;
1022    case PIPE_TEX_MIPFILTER_LINEAR:
1023       assert(lod_ipart);
1024       assert(lod_fpart);
1025       lp_build_linear_mip_levels(bld, unit,
1026                                  lod_ipart, &lod_fpart,
1027                                  &ilevel0, &ilevel1);
1028       break;
1029    }
1030
1031    /*
1032     * Get/interpolate texture colors.
1033     */
1034
1035    for (chan = 0; chan < 4; ++chan) {
1036      texels[chan] = lp_build_alloca(bld->gallivm, bld->texel_bld.vec_type, "");
1037      lp_build_name(texels[chan], "sampler%u_texel_%c_var", unit, "xyzw"[chan]);
1038    }
1039
1040    if (min_filter == mag_filter) {
1041       /* no need to distinquish between minification and magnification */
1042       lp_build_sample_mipmap(bld, unit,
1043                              min_filter, mip_filter,
1044                              s, t, r,
1045                              ilevel0, ilevel1, lod_fpart,
1046                              texels);
1047    }
1048    else {
1049       /* Emit conditional to choose min image filter or mag image filter
1050        * depending on the lod being > 0 or <= 0, respectively.
1051        */
1052       struct lp_build_if_state if_ctx;
1053       LLVMValueRef minify;
1054
1055       /* minify = lod >= 0.0 */
1056       minify = LLVMBuildICmp(builder, LLVMIntSGE,
1057                              lod_ipart, int_bld->zero, "");
1058
1059       lp_build_if(&if_ctx, bld->gallivm, minify);
1060       {
1061          /* Use the minification filter */
1062          lp_build_sample_mipmap(bld, unit,
1063                                 min_filter, mip_filter,
1064                                 s, t, r,
1065                                 ilevel0, ilevel1, lod_fpart,
1066                                 texels);
1067       }
1068       lp_build_else(&if_ctx);
1069       {
1070          /* Use the magnification filter */
1071          lp_build_sample_mipmap(bld, unit,
1072                                 mag_filter, PIPE_TEX_MIPFILTER_NONE,
1073                                 s, t, r,
1074                                 ilevel0, NULL, NULL,
1075                                 texels);
1076       }
1077       lp_build_endif(&if_ctx);
1078    }
1079
1080    for (chan = 0; chan < 4; ++chan) {
1081      colors_out[chan] = LLVMBuildLoad(builder, texels[chan], "");
1082      lp_build_name(colors_out[chan], "sampler%u_texel_%c", unit, "xyzw"[chan]);
1083    }
1084 }
1085
1086
1087 /**
1088  * Do shadow test/comparison.
1089  * \param p  the texcoord Z (aka R, aka P) component
1090  * \param texel  the texel to compare against (use the X channel)
1091  */
1092 static void
1093 lp_build_sample_compare(struct lp_build_sample_context *bld,
1094                         LLVMValueRef p,
1095                         LLVMValueRef texel[4])
1096 {
1097    struct lp_build_context *texel_bld = &bld->texel_bld;
1098    LLVMBuilderRef builder = bld->gallivm->builder;
1099    LLVMValueRef res;
1100    const unsigned chan = 0;
1101
1102    if (bld->static_state->compare_mode == PIPE_TEX_COMPARE_NONE)
1103       return;
1104
1105    /* debug code */
1106    if (0) {
1107       LLVMValueRef indx = lp_build_const_int32(bld->gallivm, 0);
1108       LLVMValueRef coord = LLVMBuildExtractElement(builder, p, indx, "");
1109       LLVMValueRef tex = LLVMBuildExtractElement(builder, texel[chan], indx, "");
1110       lp_build_printf(bld->gallivm, "shadow compare coord %f to texture %f\n",
1111                       coord, tex);
1112    }
1113
1114    /* Clamp p coords to [0,1] */
1115    p = lp_build_clamp(&bld->coord_bld, p,
1116                       bld->coord_bld.zero,
1117                       bld->coord_bld.one);
1118
1119    /* result = (p FUNC texel) ? 1 : 0 */
1120    res = lp_build_cmp(texel_bld, bld->static_state->compare_func,
1121                       p, texel[chan]);
1122    res = lp_build_select(texel_bld, res, texel_bld->one, texel_bld->zero);
1123
1124    /* XXX returning result for default GL_DEPTH_TEXTURE_MODE = GL_LUMINANCE */
1125    texel[0] =
1126    texel[1] =
1127    texel[2] = res;
1128    texel[3] = texel_bld->one;
1129 }
1130
1131
1132 /**
1133  * Just set texels to white instead of actually sampling the texture.
1134  * For debugging.
1135  */
1136 void
1137 lp_build_sample_nop(struct gallivm_state *gallivm, struct lp_type type,
1138                     LLVMValueRef texel_out[4])
1139 {
1140    LLVMValueRef one = lp_build_one(gallivm, type);
1141    unsigned chan;
1142
1143    for (chan = 0; chan < 4; chan++) {
1144       texel_out[chan] = one;
1145    }
1146 }
1147
1148
1149 /**
1150  * Build texture sampling code.
1151  * 'texel' will return a vector of four LLVMValueRefs corresponding to
1152  * R, G, B, A.
1153  * \param type  vector float type to use for coords, etc.
1154  * \param ddx  partial derivatives of (s,t,r,q) with respect to x
1155  * \param ddy  partial derivatives of (s,t,r,q) with respect to y
1156  */
1157 void
1158 lp_build_sample_soa(struct gallivm_state *gallivm,
1159                     const struct lp_sampler_static_state *static_state,
1160                     struct lp_sampler_dynamic_state *dynamic_state,
1161                     struct lp_type type,
1162                     unsigned unit,
1163                     unsigned num_coords,
1164                     const LLVMValueRef *coords,
1165                     const LLVMValueRef ddx[4],
1166                     const LLVMValueRef ddy[4],
1167                     LLVMValueRef lod_bias, /* optional */
1168                     LLVMValueRef explicit_lod, /* optional */
1169                     LLVMValueRef texel_out[4])
1170 {
1171    unsigned dims = texture_dims(static_state->target);
1172    struct lp_build_sample_context bld;
1173    LLVMTypeRef i32t = LLVMInt32TypeInContext(gallivm->context);
1174    LLVMBuilderRef builder = gallivm->builder;
1175    LLVMValueRef s;
1176    LLVMValueRef t;
1177    LLVMValueRef r;
1178    struct lp_type float_vec_type;
1179
1180    if (0) {
1181       enum pipe_format fmt = static_state->format;
1182       debug_printf("Sample from %s\n", util_format_name(fmt));
1183    }
1184
1185    assert(type.floating);
1186
1187    /* Setup our build context */
1188    memset(&bld, 0, sizeof bld);
1189    bld.gallivm = gallivm;
1190    bld.static_state = static_state;
1191    bld.dynamic_state = dynamic_state;
1192    bld.format_desc = util_format_description(static_state->format);
1193    bld.dims = dims;
1194
1195    bld.float_type = lp_type_float(32);
1196    bld.int_type = lp_type_int(32);
1197    bld.coord_type = type;
1198    bld.int_coord_type = lp_int_type(type);
1199    bld.float_size_type = lp_type_float(32);
1200    bld.float_size_type.length = dims > 1 ? 4 : 1;
1201    bld.int_size_type = lp_int_type(bld.float_size_type);
1202    bld.texel_type = type;
1203
1204    float_vec_type = lp_type_float_vec(32);
1205
1206    lp_build_context_init(&bld.float_bld, gallivm, bld.float_type);
1207    lp_build_context_init(&bld.float_vec_bld, gallivm, float_vec_type);
1208    lp_build_context_init(&bld.int_bld, gallivm, bld.int_type);
1209    lp_build_context_init(&bld.coord_bld, gallivm, bld.coord_type);
1210    lp_build_context_init(&bld.int_coord_bld, gallivm, bld.int_coord_type);
1211    lp_build_context_init(&bld.int_size_bld, gallivm, bld.int_size_type);
1212    lp_build_context_init(&bld.float_size_bld, gallivm, bld.float_size_type);
1213    lp_build_context_init(&bld.texel_bld, gallivm, bld.texel_type);
1214
1215    /* Get the dynamic state */
1216    bld.width = dynamic_state->width(dynamic_state, gallivm, unit);
1217    bld.height = dynamic_state->height(dynamic_state, gallivm, unit);
1218    bld.depth = dynamic_state->depth(dynamic_state, gallivm, unit);
1219    bld.row_stride_array = dynamic_state->row_stride(dynamic_state, gallivm, unit);
1220    bld.img_stride_array = dynamic_state->img_stride(dynamic_state, gallivm, unit);
1221    bld.data_array = dynamic_state->data_ptr(dynamic_state, gallivm, unit);
1222    /* Note that data_array is an array[level] of pointers to texture images */
1223
1224    s = coords[0];
1225    t = coords[1];
1226    r = coords[2];
1227
1228    /* width, height, depth as single int vector */
1229    if (dims <= 1) {
1230       bld.int_size = bld.width;
1231    }
1232    else {
1233       bld.int_size = LLVMBuildInsertElement(builder, bld.int_size_bld.undef,
1234                                             bld.width, LLVMConstInt(i32t, 0, 0), "");
1235       if (dims >= 2) {
1236          bld.int_size = LLVMBuildInsertElement(builder, bld.int_size,
1237                                                bld.height, LLVMConstInt(i32t, 1, 0), "");
1238          if (dims >= 3) {
1239             bld.int_size = LLVMBuildInsertElement(builder, bld.int_size,
1240                                                   bld.depth, LLVMConstInt(i32t, 2, 0), "");
1241          }
1242       }
1243    }
1244
1245    if (0) {
1246       /* For debug: no-op texture sampling */
1247       lp_build_sample_nop(gallivm, bld.texel_type, texel_out);
1248    }
1249    else if (util_format_fits_8unorm(bld.format_desc) &&
1250             lp_is_simple_wrap_mode(static_state->wrap_s) &&
1251             lp_is_simple_wrap_mode(static_state->wrap_t)) {
1252       /* do sampling/filtering with fixed pt arithmetic */
1253       lp_build_sample_aos(&bld, unit, s, t, r, ddx, ddy,
1254                           lod_bias, explicit_lod,
1255                           texel_out);
1256    }
1257
1258    else {
1259       if ((gallivm_debug & GALLIVM_DEBUG_PERF) &&
1260           util_format_fits_8unorm(bld.format_desc)) {
1261          debug_printf("%s: using floating point linear filtering for %s\n",
1262                       __FUNCTION__, bld.format_desc->short_name);
1263          debug_printf("  min_img %d  mag_img %d  mip %d  wraps %d  wrapt %d\n",
1264                       static_state->min_img_filter,
1265                       static_state->mag_img_filter,
1266                       static_state->min_mip_filter,
1267                       static_state->wrap_s,
1268                       static_state->wrap_t);
1269       }
1270
1271       lp_build_sample_general(&bld, unit, s, t, r, ddx, ddy,
1272                               lod_bias, explicit_lod,
1273                               texel_out);
1274    }
1275
1276    lp_build_sample_compare(&bld, r, texel_out);
1277
1278    apply_sampler_swizzle(&bld, texel_out);
1279 }