src/gallium/auxiliary/gallivm/lp_bld_sample_soa.c

   1 /**************************************************************************
   2  *
   3  * Copyright 2009 VMware, Inc.
   4  * All Rights Reserved.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a
   7  * 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, sub license, 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 portions
  16  * of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  19  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  20  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
  21  * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR
  22  * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  23  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  24  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  *
  26  **************************************************************************/
  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    LLVMValueRef offset;
  88    LLVMValueRef i, j;
  89    LLVMValueRef use_border = NULL;
  90
  91    /* use_border = x < 0 || x >= width || y < 0 || y >= height */
  92    if (lp_sampler_wrap_mode_uses_border_color(static_state->wrap_s,
  93                                               static_state->min_img_filter,
  94                                               static_state->mag_img_filter)) {
  95       LLVMValueRef b1, b2;
  96       b1 = lp_build_cmp(int_coord_bld, PIPE_FUNC_LESS, x, int_coord_bld->zero);
  97       b2 = lp_build_cmp(int_coord_bld, PIPE_FUNC_GEQUAL, x, width);
  98       use_border = LLVMBuildOr(bld->builder, b1, b2, "b1_or_b2");
  99    }
 100
 101    if (dims >= 2 &&
 102        lp_sampler_wrap_mode_uses_border_color(static_state->wrap_t,
 103                                               static_state->min_img_filter,
 104                                               static_state->mag_img_filter)) {
 105       LLVMValueRef b1, b2;
 106       b1 = lp_build_cmp(int_coord_bld, PIPE_FUNC_LESS, y, int_coord_bld->zero);
 107       b2 = lp_build_cmp(int_coord_bld, PIPE_FUNC_GEQUAL, y, height);
 108       if (use_border) {
 109          use_border = LLVMBuildOr(bld->builder, use_border, b1, "ub_or_b1");
 110          use_border = LLVMBuildOr(bld->builder, use_border, b2, "ub_or_b2");
 111       }
 112       else {
 113          use_border = LLVMBuildOr(bld->builder, b1, b2, "b1_or_b2");
 114       }
 115    }
 116
 117    if (dims == 3 &&
 118        lp_sampler_wrap_mode_uses_border_color(static_state->wrap_r,
 119                                               static_state->min_img_filter,
 120                                               static_state->mag_img_filter)) {
 121       LLVMValueRef b1, b2;
 122       b1 = lp_build_cmp(int_coord_bld, PIPE_FUNC_LESS, z, int_coord_bld->zero);
 123       b2 = lp_build_cmp(int_coord_bld, PIPE_FUNC_GEQUAL, z, depth);
 124       if (use_border) {
 125          use_border = LLVMBuildOr(bld->builder, use_border, b1, "ub_or_b1");
 126          use_border = LLVMBuildOr(bld->builder, use_border, b2, "ub_or_b2");
 127       }
 128       else {
 129          use_border = LLVMBuildOr(bld->builder, b1, b2, "b1_or_b2");
 130       }
 131    }
 132
 133    /* convert x,y,z coords to linear offset from start of texture, in bytes */
 134    lp_build_sample_offset(&bld->int_coord_bld,
 135                           bld->format_desc,
 136                           x, y, z, y_stride, z_stride,
 137                           &offset, &i, &j);
 138
 139    if (use_border) {
 140       /* If we can sample the border color, it means that texcoords may
 141        * lie outside the bounds of the texture image.  We need to do
 142        * something to prevent reading out of bounds and causing a segfault.
 143        *
 144        * Simply AND the texture coords with !use_border.  This will cause
 145        * coords which are out of bounds to become zero.  Zero's guaranteed
 146        * to be inside the texture image.
 147        */
 148       offset = lp_build_andnot(&bld->int_coord_bld, offset, use_border);
 149    }
 150
 151    lp_build_fetch_rgba_soa(bld->builder,
 152                            bld->format_desc,
 153                            bld->texel_type,
 154                            data_ptr, offset,
 155                            i, j,
 156                            texel_out);
 157
 158    /*
 159     * Note: if we find an app which frequently samples the texture border
 160     * we might want to implement a true conditional here to avoid sampling
 161     * the texture whenever possible (since that's quite a bit of code).
 162     * Ex:
 163     *   if (use_border) {
 164     *      texel = border_color;
 165     *   }
 166     *   else {
 167     *      texel = sample_texture(coord);
 168     *   }
 169     * As it is now, we always sample the texture, then selectively replace
 170     * the texel color results with the border color.
 171     */
 172
 173    if (use_border) {
 174       /* select texel color or border color depending on use_border */
 175       LLVMValueRef border_color_ptr =
 176          bld->dynamic_state->border_color(bld->dynamic_state,
 177                                           bld->builder, unit);
 178       int chan;
 179       for (chan = 0; chan < 4; chan++) {
 180          LLVMValueRef border_chan =
 181             lp_build_array_get(bld->builder, border_color_ptr,
 182                                lp_build_const_int32(chan));
 183          LLVMValueRef border_chan_vec =
 184             lp_build_broadcast_scalar(&bld->float_vec_bld, border_chan);
 185          texel_out[chan] = lp_build_select(&bld->texel_bld, use_border,
 186                                            border_chan_vec, texel_out[chan]);
 187       }
 188    }
 189
 190    apply_sampler_swizzle(bld, texel_out);
 191 }
 192
 193
 194 /**
 195  * Helper to compute the mirror function for the PIPE_WRAP_MIRROR modes.
 196  */
 197 static LLVMValueRef
 198 lp_build_coord_mirror(struct lp_build_sample_context *bld,
 199                       LLVMValueRef coord)
 200 {
 201    struct lp_build_context *coord_bld = &bld->coord_bld;
 202    struct lp_build_context *int_coord_bld = &bld->int_coord_bld;
 203    LLVMValueRef fract, flr, isOdd;
 204
 205    lp_build_ifloor_fract(coord_bld, coord, &flr, &fract);
 206
 207    /* isOdd = flr & 1 */
 208    isOdd = LLVMBuildAnd(bld->builder, flr, int_coord_bld->one, "");
 209
 210    /* make coord positive or negative depending on isOdd */
 211    coord = lp_build_set_sign(coord_bld, fract, isOdd);
 212
 213    /* convert isOdd to float */
 214    isOdd = lp_build_int_to_float(coord_bld, isOdd);
 215
 216    /* add isOdd to coord */
 217    coord = lp_build_add(coord_bld, coord, isOdd);
 218
 219    return coord;
 220 }
 221
 222
 223 /**
 224  * Build LLVM code for texture wrap mode for linear filtering.
 225  * \param x0_out  returns first integer texcoord
 226  * \param x1_out  returns second integer texcoord
 227  * \param weight_out  returns linear interpolation weight
 228  */
 229 static void
 230 lp_build_sample_wrap_linear(struct lp_build_sample_context *bld,
 231                             LLVMValueRef coord,
 232                             LLVMValueRef length,
 233                             LLVMValueRef length_f,
 234                             boolean is_pot,
 235                             unsigned wrap_mode,
 236                             LLVMValueRef *x0_out,
 237                             LLVMValueRef *x1_out,
 238                             LLVMValueRef *weight_out)
 239 {
 240    struct lp_build_context *coord_bld = &bld->coord_bld;
 241    struct lp_build_context *int_coord_bld = &bld->int_coord_bld;
 242    LLVMValueRef half = lp_build_const_vec(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(bld->builder, coord0, length_minus_one, "");
 257          coord1 = LLVMBuildAnd(bld->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(bld->builder, coord0, bias, "");
 264          coord0 = LLVMBuildURem(bld->builder, coord0, length, "");
 265          mask = lp_build_compare(bld->builder, int_coord_bld->type,
 266                                  PIPE_FUNC_NOTEQUAL, coord0, length_minus_one);
 267          coord1 = LLVMBuildAnd(bld->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             /* clamp to length max */
 298             coord = lp_build_min(coord_bld, coord, length_f);
 299             /* subtract 0.5 */
 300             coord = lp_build_sub(coord_bld, coord, half);
 301             /* clamp to [0, length - 0.5] */
 302             coord = lp_build_max(coord_bld, coord, coord_bld->zero);
 303          }
 304          /* XXX this is odd normalized ranges from 0 to length-0.5 after denorm
 305             but non-normalized ranges from to 0.5 to length-0.5 after clamp.
 306             Is this missing the sub 0.5? */
 307          else {
 308             LLVMValueRef min, max;
 309             /* clamp to [0.5, length - 0.5] */
 310             min = half;
 311             max = lp_build_sub(coord_bld, length_f, min);
 312             coord = lp_build_clamp(coord_bld, coord, min, max);
 313          }
 314          /* convert to int, compute lerp weight */
 315          lp_build_ifloor_fract(&abs_coord_bld, coord, &coord0, &weight);
 316          coord1 = lp_build_add(int_coord_bld, coord0, int_coord_bld->one);
 317          /* coord1 = min(coord1, length-1) */
 318          coord1 = lp_build_min(int_coord_bld, coord1, length_minus_one);
 319          break;
 320       }
 321
 322    case PIPE_TEX_WRAP_CLAMP_TO_BORDER:
 323       {
 324          LLVMValueRef min;
 325          if (bld->static_state->normalized_coords) {
 326             /* scale coord to length */
 327             coord = lp_build_mul(coord_bld, coord, length_f);
 328          }
 329          /* was: clamp to [-0.5, length + 0.5], then sub 0.5 */
 330          coord = lp_build_sub(coord_bld, coord, half);
 331          min = lp_build_const_vec(coord_bld->type, -1.0F);
 332          coord = lp_build_clamp(coord_bld, coord, min, length_f);
 333          /* convert to int, compute lerp weight */
 334          lp_build_ifloor_fract(coord_bld, coord, &coord0, &weight);
 335          coord1 = lp_build_add(int_coord_bld, coord0, int_coord_bld->one);
 336       }
 337       break;
 338
 339    case PIPE_TEX_WRAP_MIRROR_REPEAT:
 340       /* compute mirror function */
 341       coord = lp_build_coord_mirror(bld, coord);
 342
 343       /* scale coord to length */
 344       coord = lp_build_mul(coord_bld, coord, length_f);
 345       coord = lp_build_sub(coord_bld, coord, half);
 346
 347       /* convert to int, compute lerp weight */
 348       lp_build_ifloor_fract(coord_bld, coord, &coord0, &weight);
 349       coord1 = lp_build_add(int_coord_bld, coord0, int_coord_bld->one);
 350
 351       /* coord0 = max(coord0, 0) */
 352       coord0 = lp_build_max(int_coord_bld, coord0, int_coord_bld->zero);
 353       /* coord1 = min(coord1, length-1) */
 354       coord1 = lp_build_min(int_coord_bld, coord1, length_minus_one);
 355       break;
 356
 357    case PIPE_TEX_WRAP_MIRROR_CLAMP:
 358       coord = lp_build_abs(coord_bld, coord);
 359
 360       if (bld->static_state->normalized_coords) {
 361          /* scale coord to length */
 362          coord = lp_build_mul(coord_bld, coord, length_f);
 363       }
 364
 365       /* clamp to [0, length] */
 366       coord = lp_build_min(coord_bld, coord, length_f);
 367
 368       coord = lp_build_sub(coord_bld, coord, half);
 369
 370       /* convert to int, compute lerp weight */
 371       lp_build_ifloor_fract(coord_bld, coord, &coord0, &weight);
 372       coord1 = lp_build_add(int_coord_bld, coord0, int_coord_bld->one);
 373       break;
 374
 375    case PIPE_TEX_WRAP_MIRROR_CLAMP_TO_EDGE:
 376       {
 377          LLVMValueRef min, max;
 378          struct lp_build_context abs_coord_bld = bld->coord_bld;
 379          abs_coord_bld.type.sign = FALSE;
 380          coord = lp_build_abs(coord_bld, coord);
 381
 382          if (bld->static_state->normalized_coords) {
 383             /* scale coord to length */
 384             coord = lp_build_mul(coord_bld, coord, length_f);
 385          }
 386
 387          /* clamp to [0.5, length - 0.5] */
 388          min = half;
 389          max = lp_build_sub(coord_bld, length_f, min);
 390          coord = lp_build_clamp(coord_bld, coord, min, max);
 391
 392          coord = lp_build_sub(coord_bld, coord, half);
 393
 394          /* convert to int, compute lerp weight */
 395          lp_build_ifloor_fract(&abs_coord_bld, coord, &coord0, &weight);
 396          coord1 = lp_build_add(int_coord_bld, coord0, int_coord_bld->one);
 397       }
 398       break;
 399
 400    case PIPE_TEX_WRAP_MIRROR_CLAMP_TO_BORDER:
 401       {
 402          coord = lp_build_abs(coord_bld, coord);
 403
 404          if (bld->static_state->normalized_coords) {
 405             /* scale coord to length */
 406             coord = lp_build_mul(coord_bld, coord, length_f);
 407          }
 408
 409          /* was: clamp to [-0.5, length + 0.5] then sub 0.5 */
 410          /* skip -0.5 clamp (always positive), do sub first */
 411          coord = lp_build_sub(coord_bld, coord, half);
 412          coord = lp_build_min(coord_bld, coord, length_f);
 413
 414          /* convert to int, compute lerp weight */
 415          lp_build_ifloor_fract(coord_bld, coord, &coord0, &weight);
 416          coord1 = lp_build_add(int_coord_bld, coord0, int_coord_bld->one);
 417       }
 418       break;
 419
 420    default:
 421       assert(0);
 422       coord0 = NULL;
 423       coord1 = NULL;
 424       weight = NULL;
 425    }
 426
 427    *x0_out = coord0;
 428    *x1_out = coord1;
 429    *weight_out = weight;
 430 }
 431
 432
 433 /**
 434  * Build LLVM code for texture wrap mode for nearest filtering.
 435  * \param coord  the incoming texcoord (nominally in [0,1])
 436  * \param length  the texture size along one dimension, as int vector
 437  * \param is_pot  if TRUE, length is a power of two
 438  * \param wrap_mode  one of PIPE_TEX_WRAP_x
 439  */
 440 static LLVMValueRef
 441 lp_build_sample_wrap_nearest(struct lp_build_sample_context *bld,
 442                              LLVMValueRef coord,
 443                              LLVMValueRef length,
 444                              LLVMValueRef length_f,
 445                              boolean is_pot,
 446                              unsigned wrap_mode)
 447 {
 448    struct lp_build_context *coord_bld = &bld->coord_bld;
 449    struct lp_build_context *int_coord_bld = &bld->int_coord_bld;
 450    LLVMValueRef length_minus_one = lp_build_sub(int_coord_bld, length, int_coord_bld->one);
 451    LLVMValueRef icoord;
 452
 453    switch(wrap_mode) {
 454    case PIPE_TEX_WRAP_REPEAT:
 455       coord = lp_build_mul(coord_bld, coord, length_f);
 456       icoord = lp_build_ifloor(coord_bld, coord);
 457       if (is_pot)
 458          icoord = LLVMBuildAnd(bld->builder, icoord, length_minus_one, "");
 459       else {
 460          /* Add a bias to the texcoord to handle negative coords */
 461          LLVMValueRef bias = lp_build_mul_imm(int_coord_bld, length, 1024);
 462          icoord = LLVMBuildAdd(bld->builder, icoord, bias, "");
 463          icoord = LLVMBuildURem(bld->builder, icoord, length, "");
 464       }
 465       break;
 466
 467    case PIPE_TEX_WRAP_CLAMP:
 468    case PIPE_TEX_WRAP_CLAMP_TO_EDGE:
 469       if (bld->static_state->normalized_coords) {
 470          /* scale coord to length */
 471          coord = lp_build_mul(coord_bld, coord, length_f);
 472       }
 473
 474       /* floor */
 475       /* use itrunc instead since we clamp to 0 anyway */
 476       icoord = lp_build_itrunc(coord_bld, coord);
 477
 478       /* clamp to [0, length - 1]. */
 479       icoord = lp_build_clamp(int_coord_bld, icoord, int_coord_bld->zero,
 480                               length_minus_one);
 481       break;
 482
 483    case PIPE_TEX_WRAP_CLAMP_TO_BORDER:
 484       /* Note: this is the same as CLAMP_TO_EDGE, except min = -min */
 485       {
 486          LLVMValueRef min, max;
 487
 488          if (bld->static_state->normalized_coords) {
 489             /* scale coord to length */
 490             coord = lp_build_mul(coord_bld, coord, length_f);
 491          }
 492
 493          icoord = lp_build_ifloor(coord_bld, coord);
 494
 495          /* clamp to [-1, length] */
 496          min = lp_build_negate(int_coord_bld, int_coord_bld->one);
 497          max = length;
 498          icoord = lp_build_clamp(int_coord_bld, icoord, min, max);
 499       }
 500       break;
 501
 502    case PIPE_TEX_WRAP_MIRROR_REPEAT:
 503       /* compute mirror function */
 504       coord = lp_build_coord_mirror(bld, coord);
 505
 506       /* scale coord to length */
 507       assert(bld->static_state->normalized_coords);
 508       coord = lp_build_mul(coord_bld, coord, length_f);
 509
 510       /* itrunc == ifloor here */
 511       icoord = lp_build_itrunc(coord_bld, coord);
 512
 513       /* clamp to [0, length - 1] */
 514       icoord = lp_build_min(int_coord_bld, icoord, length_minus_one);
 515       break;
 516
 517    case PIPE_TEX_WRAP_MIRROR_CLAMP:
 518    case PIPE_TEX_WRAP_MIRROR_CLAMP_TO_EDGE:
 519       coord = lp_build_abs(coord_bld, coord);
 520
 521       if (bld->static_state->normalized_coords) {
 522          /* scale coord to length */
 523          coord = lp_build_mul(coord_bld, coord, length_f);
 524       }
 525
 526       /* itrunc == ifloor here */
 527       icoord = lp_build_itrunc(coord_bld, coord);
 528
 529       /* clamp to [0, length - 1] */
 530       icoord = lp_build_min(int_coord_bld, icoord, length_minus_one);
 531       break;
 532
 533    case PIPE_TEX_WRAP_MIRROR_CLAMP_TO_BORDER:
 534       coord = lp_build_abs(coord_bld, coord);
 535
 536       if (bld->static_state->normalized_coords) {
 537          /* scale coord to length */
 538          coord = lp_build_mul(coord_bld, coord, length_f);
 539       }
 540
 541       /* itrunc == ifloor here */
 542       icoord = lp_build_itrunc(coord_bld, coord);
 543
 544       /* clamp to [0, length] */
 545       icoord = lp_build_min(int_coord_bld, icoord, length);
 546       break;
 547
 548    default:
 549       assert(0);
 550       icoord = NULL;
 551    }
 552
 553    return icoord;
 554 }
 555
 556
 557 /**
 558  * Generate code to sample a mipmap level with nearest filtering.
 559  * If sampling a cube texture, r = cube face in [0,5].
 560  */
 561 static void
 562 lp_build_sample_image_nearest(struct lp_build_sample_context *bld,
 563                               unsigned unit,
 564                               LLVMValueRef size,
 565                               LLVMValueRef row_stride_vec,
 566                               LLVMValueRef img_stride_vec,
 567                               LLVMValueRef data_ptr,
 568                               LLVMValueRef s,
 569                               LLVMValueRef t,
 570                               LLVMValueRef r,
 571                               LLVMValueRef colors_out[4])
 572 {
 573    const unsigned dims = bld->dims;
 574    LLVMValueRef width_vec;
 575    LLVMValueRef height_vec;
 576    LLVMValueRef depth_vec;
 577    LLVMValueRef flt_size;
 578    LLVMValueRef flt_width_vec;
 579    LLVMValueRef flt_height_vec;
 580    LLVMValueRef flt_depth_vec;
 581    LLVMValueRef x, y, z;
 582
 583    lp_build_extract_image_sizes(bld,
 584                                 bld->int_size_type,
 585                                 bld->int_coord_type,
 586                                 size,
 587                                 &width_vec, &height_vec, &depth_vec);
 588
 589    flt_size = lp_build_int_to_float(&bld->float_size_bld, size);
 590
 591    lp_build_extract_image_sizes(bld,
 592                                 bld->float_size_type,
 593                                 bld->coord_type,
 594                                 flt_size,
 595                                 &flt_width_vec, &flt_height_vec, &flt_depth_vec);
 596
 597    /*
 598     * Compute integer texcoords.
 599     */
 600    x = lp_build_sample_wrap_nearest(bld, s, width_vec, flt_width_vec,
 601                                     bld->static_state->pot_width,
 602                                     bld->static_state->wrap_s);
 603    lp_build_name(x, "tex.x.wrapped");
 604
 605    if (dims >= 2) {
 606       y = lp_build_sample_wrap_nearest(bld, t, height_vec, flt_height_vec,
 607                                        bld->static_state->pot_height,
 608                                        bld->static_state->wrap_t);
 609       lp_build_name(y, "tex.y.wrapped");
 610
 611       if (dims == 3) {
 612          z = lp_build_sample_wrap_nearest(bld, r, depth_vec, flt_depth_vec,
 613                                           bld->static_state->pot_depth,
 614                                           bld->static_state->wrap_r);
 615          lp_build_name(z, "tex.z.wrapped");
 616       }
 617       else if (bld->static_state->target == PIPE_TEXTURE_CUBE) {
 618          z = r;
 619       }
 620       else {
 621          z = NULL;
 622       }
 623    }
 624    else {
 625       y = z = NULL;
 626    }
 627
 628    /*
 629     * Get texture colors.
 630     */
 631    lp_build_sample_texel_soa(bld, unit,
 632                              width_vec, height_vec, depth_vec,
 633                              x, y, z,
 634                              row_stride_vec, img_stride_vec,
 635                              data_ptr, colors_out);
 636 }
 637
 638
 639 /**
 640  * Generate code to sample a mipmap level with linear filtering.
 641  * If sampling a cube texture, r = cube face in [0,5].
 642  */
 643 static void
 644 lp_build_sample_image_linear(struct lp_build_sample_context *bld,
 645                              unsigned unit,
 646                              LLVMValueRef size,
 647                              LLVMValueRef row_stride_vec,
 648                              LLVMValueRef img_stride_vec,
 649                              LLVMValueRef data_ptr,
 650                              LLVMValueRef s,
 651                              LLVMValueRef t,
 652                              LLVMValueRef r,
 653                              LLVMValueRef colors_out[4])
 654 {
 655    const unsigned dims = bld->dims;
 656    LLVMValueRef width_vec;
 657    LLVMValueRef height_vec;
 658    LLVMValueRef depth_vec;
 659    LLVMValueRef flt_size;
 660    LLVMValueRef flt_width_vec;
 661    LLVMValueRef flt_height_vec;
 662    LLVMValueRef flt_depth_vec;
 663    LLVMValueRef x0, y0, z0, x1, y1, z1;
 664    LLVMValueRef s_fpart, t_fpart, r_fpart;
 665    LLVMValueRef neighbors[2][2][4];
 666    int chan;
 667
 668    lp_build_extract_image_sizes(bld,
 669                                 bld->int_size_type,
 670                                 bld->int_coord_type,
 671                                 size,
 672                                 &width_vec, &height_vec, &depth_vec);
 673
 674    flt_size = lp_build_int_to_float(&bld->float_size_bld, size);
 675
 676    lp_build_extract_image_sizes(bld,
 677                                 bld->float_size_type,
 678                                 bld->coord_type,
 679                                 flt_size,
 680                                 &flt_width_vec, &flt_height_vec, &flt_depth_vec);
 681
 682    /*
 683     * Compute integer texcoords.
 684     */
 685    lp_build_sample_wrap_linear(bld, s, width_vec, flt_width_vec,
 686                                bld->static_state->pot_width,
 687                                bld->static_state->wrap_s,
 688                                &x0, &x1, &s_fpart);
 689    lp_build_name(x0, "tex.x0.wrapped");
 690    lp_build_name(x1, "tex.x1.wrapped");
 691
 692    if (dims >= 2) {
 693       lp_build_sample_wrap_linear(bld, t, height_vec, flt_height_vec,
 694                                   bld->static_state->pot_height,
 695                                   bld->static_state->wrap_t,
 696                                   &y0, &y1, &t_fpart);
 697       lp_build_name(y0, "tex.y0.wrapped");
 698       lp_build_name(y1, "tex.y1.wrapped");
 699
 700       if (dims == 3) {
 701          lp_build_sample_wrap_linear(bld, r, depth_vec, flt_depth_vec,
 702                                      bld->static_state->pot_depth,
 703                                      bld->static_state->wrap_r,
 704                                      &z0, &z1, &r_fpart);
 705          lp_build_name(z0, "tex.z0.wrapped");
 706          lp_build_name(z1, "tex.z1.wrapped");
 707       }
 708       else if (bld->static_state->target == PIPE_TEXTURE_CUBE) {
 709          z0 = z1 = r;  /* cube face */
 710          r_fpart = NULL;
 711       }
 712       else {
 713          z0 = z1 = NULL;
 714          r_fpart = NULL;
 715       }
 716    }
 717    else {
 718       y0 = y1 = t_fpart = NULL;
 719       z0 = z1 = r_fpart = NULL;
 720    }
 721
 722    /*
 723     * Get texture colors.
 724     */
 725    /* get x0/x1 texels */
 726    lp_build_sample_texel_soa(bld, unit,
 727                              width_vec, height_vec, depth_vec,
 728                              x0, y0, z0,
 729                              row_stride_vec, img_stride_vec,
 730                              data_ptr, neighbors[0][0]);
 731    lp_build_sample_texel_soa(bld, unit,
 732                              width_vec, height_vec, depth_vec,
 733                              x1, y0, z0,
 734                              row_stride_vec, img_stride_vec,
 735                              data_ptr, neighbors[0][1]);
 736
 737    if (dims == 1) {
 738       /* Interpolate two samples from 1D image to produce one color */
 739       for (chan = 0; chan < 4; chan++) {
 740          colors_out[chan] = lp_build_lerp(&bld->texel_bld, s_fpart,
 741                                           neighbors[0][0][chan],
 742                                           neighbors[0][1][chan]);
 743       }
 744    }
 745    else {
 746       /* 2D/3D texture */
 747       LLVMValueRef colors0[4];
 748
 749       /* get x0/x1 texels at y1 */
 750       lp_build_sample_texel_soa(bld, unit,
 751                                 width_vec, height_vec, depth_vec,
 752                                 x0, y1, z0,
 753                                 row_stride_vec, img_stride_vec,
 754                                 data_ptr, neighbors[1][0]);
 755       lp_build_sample_texel_soa(bld, unit,
 756                                 width_vec, height_vec, depth_vec,
 757                                 x1, y1, z0,
 758                                 row_stride_vec, img_stride_vec,
 759                                 data_ptr, neighbors[1][1]);
 760
 761       /* Bilinear interpolate the four samples from the 2D image / 3D slice */
 762       for (chan = 0; chan < 4; chan++) {
 763          colors0[chan] = lp_build_lerp_2d(&bld->texel_bld,
 764                                           s_fpart, t_fpart,
 765                                           neighbors[0][0][chan],
 766                                           neighbors[0][1][chan],
 767                                           neighbors[1][0][chan],
 768                                           neighbors[1][1][chan]);
 769       }
 770
 771       if (dims == 3) {
 772          LLVMValueRef neighbors1[2][2][4];
 773          LLVMValueRef colors1[4];
 774
 775          /* get x0/x1/y0/y1 texels at z1 */
 776          lp_build_sample_texel_soa(bld, unit,
 777                                    width_vec, height_vec, depth_vec,
 778                                    x0, y0, z1,
 779                                    row_stride_vec, img_stride_vec,
 780                                    data_ptr, neighbors1[0][0]);
 781          lp_build_sample_texel_soa(bld, unit,
 782                                    width_vec, height_vec, depth_vec,
 783                                    x1, y0, z1,
 784                                    row_stride_vec, img_stride_vec,
 785                                    data_ptr, neighbors1[0][1]);
 786          lp_build_sample_texel_soa(bld, unit,
 787                                    width_vec, height_vec, depth_vec,
 788                                    x0, y1, z1,
 789                                    row_stride_vec, img_stride_vec,
 790                                    data_ptr, neighbors1[1][0]);
 791          lp_build_sample_texel_soa(bld, unit,
 792                                    width_vec, height_vec, depth_vec,
 793                                    x1, y1, z1,
 794                                    row_stride_vec, img_stride_vec,
 795                                    data_ptr, neighbors1[1][1]);
 796
 797          /* Bilinear interpolate the four samples from the second Z slice */
 798          for (chan = 0; chan < 4; chan++) {
 799             colors1[chan] = lp_build_lerp_2d(&bld->texel_bld,
 800                                              s_fpart, t_fpart,
 801                                              neighbors1[0][0][chan],
 802                                              neighbors1[0][1][chan],
 803                                              neighbors1[1][0][chan],
 804                                              neighbors1[1][1][chan]);
 805          }
 806
 807          /* Linearly interpolate the two samples from the two 3D slices */
 808          for (chan = 0; chan < 4; chan++) {
 809             colors_out[chan] = lp_build_lerp(&bld->texel_bld,
 810                                              r_fpart,
 811                                              colors0[chan], colors1[chan]);
 812          }
 813       }
 814       else {
 815          /* 2D tex */
 816          for (chan = 0; chan < 4; chan++) {
 817             colors_out[chan] = colors0[chan];
 818          }
 819       }
 820    }
 821 }
 822
 823
 824 /**
 825  * Sample the texture/mipmap using given image filter and mip filter.
 826  * data0_ptr and data1_ptr point to the two mipmap levels to sample
 827  * from.  width0/1_vec, height0/1_vec, depth0/1_vec indicate their sizes.
 828  * If we're using nearest miplevel sampling the '1' values will be null/unused.
 829  */
 830 static void
 831 lp_build_sample_mipmap(struct lp_build_sample_context *bld,
 832                        unsigned unit,
 833                        unsigned img_filter,
 834                        unsigned mip_filter,
 835                        LLVMValueRef s,
 836                        LLVMValueRef t,
 837                        LLVMValueRef r,
 838                        LLVMValueRef ilevel0,
 839                        LLVMValueRef ilevel1,
 840                        LLVMValueRef lod_fpart,
 841                        LLVMValueRef *colors_out)
 842 {
 843    LLVMBuilderRef builder = bld->builder;
 844    LLVMValueRef size0;
 845    LLVMValueRef size1;
 846    LLVMValueRef row_stride0_vec;
 847    LLVMValueRef row_stride1_vec;
 848    LLVMValueRef img_stride0_vec;
 849    LLVMValueRef img_stride1_vec;
 850    LLVMValueRef data_ptr0;
 851    LLVMValueRef data_ptr1;
 852    LLVMValueRef colors0[4], colors1[4];
 853    unsigned chan;
 854
 855    /* sample the first mipmap level */
 856    lp_build_mipmap_level_sizes(bld, ilevel0,
 857                                &size0,
 858                                &row_stride0_vec, &img_stride0_vec);
 859    data_ptr0 = lp_build_get_mipmap_level(bld, ilevel0);
 860    if (img_filter == PIPE_TEX_FILTER_NEAREST) {
 861       lp_build_sample_image_nearest(bld, unit,
 862                                     size0,
 863                                     row_stride0_vec, img_stride0_vec,
 864                                     data_ptr0, s, t, r,
 865                                     colors0);
 866    }
 867    else {
 868       assert(img_filter == PIPE_TEX_FILTER_LINEAR);
 869       lp_build_sample_image_linear(bld, unit,
 870                                    size0,
 871                                    row_stride0_vec, img_stride0_vec,
 872                                    data_ptr0, s, t, r,
 873                                    colors0);
 874    }
 875
 876    /* Store the first level's colors in the output variables */
 877    for (chan = 0; chan < 4; chan++) {
 878        LLVMBuildStore(builder, colors0[chan], colors_out[chan]);
 879    }
 880
 881    if (mip_filter == PIPE_TEX_MIPFILTER_LINEAR) {
 882       struct lp_build_if_state if_ctx;
 883       LLVMValueRef need_lerp;
 884
 885       /* need_lerp = lod_fpart > 0 */
 886       need_lerp = LLVMBuildFCmp(builder, LLVMRealUGT,
 887                                 lod_fpart,
 888                                 bld->float_bld.zero,
 889                                 "need_lerp");
 890
 891       lp_build_if(&if_ctx, builder, need_lerp);
 892       {
 893          /* sample the second mipmap level */
 894          lp_build_mipmap_level_sizes(bld, ilevel1,
 895                                      &size1,
 896                                      &row_stride1_vec, &img_stride1_vec);
 897          data_ptr1 = lp_build_get_mipmap_level(bld, ilevel1);
 898          if (img_filter == PIPE_TEX_FILTER_NEAREST) {
 899             lp_build_sample_image_nearest(bld, unit,
 900                                           size1,
 901                                           row_stride1_vec, img_stride1_vec,
 902                                           data_ptr1, s, t, r,
 903                                           colors1);
 904          }
 905          else {
 906             lp_build_sample_image_linear(bld, unit,
 907                                          size1,
 908                                          row_stride1_vec, img_stride1_vec,
 909                                          data_ptr1, s, t, r,
 910                                          colors1);
 911          }
 912
 913          /* interpolate samples from the two mipmap levels */
 914
 915          lod_fpart = lp_build_broadcast_scalar(&bld->texel_bld, lod_fpart);
 916
 917          for (chan = 0; chan < 4; chan++) {
 918             colors0[chan] = lp_build_lerp(&bld->texel_bld, lod_fpart,
 919                                           colors0[chan], colors1[chan]);
 920             LLVMBuildStore(builder, colors0[chan], colors_out[chan]);
 921          }
 922       }
 923       lp_build_endif(&if_ctx);
 924    }
 925 }
 926
 927
 928
 929 /**
 930  * General texture sampling codegen.
 931  * This function handles texture sampling for all texture targets (1D,
 932  * 2D, 3D, cube) and all filtering modes.
 933  */
 934 static void
 935 lp_build_sample_general(struct lp_build_sample_context *bld,
 936                         unsigned unit,
 937                         LLVMValueRef s,
 938                         LLVMValueRef t,
 939                         LLVMValueRef r,
 940                         const LLVMValueRef *ddx,
 941                         const LLVMValueRef *ddy,
 942                         LLVMValueRef lod_bias, /* optional */
 943                         LLVMValueRef explicit_lod, /* optional */
 944                         LLVMValueRef *colors_out)
 945 {
 946    struct lp_build_context *int_bld = &bld->int_bld;
 947    LLVMBuilderRef builder = bld->builder;
 948    const unsigned mip_filter = bld->static_state->min_mip_filter;
 949    const unsigned min_filter = bld->static_state->min_img_filter;
 950    const unsigned mag_filter = bld->static_state->mag_img_filter;
 951    LLVMValueRef lod_ipart = NULL, lod_fpart = NULL;
 952    LLVMValueRef ilevel0, ilevel1 = NULL;
 953    LLVMValueRef face_ddx[4], face_ddy[4];
 954    LLVMValueRef texels[4];
 955    LLVMTypeRef i32t = LLVMInt32Type();
 956    LLVMValueRef i32t_zero = LLVMConstInt(i32t, 0, 0);
 957    unsigned chan;
 958
 959    /*
 960    printf("%s mip %d  min %d  mag %d\n", __FUNCTION__,
 961           mip_filter, min_filter, mag_filter);
 962    */
 963
 964    /*
 965     * Choose cube face, recompute texcoords and derivatives for the chosen face.
 966     */
 967    if (bld->static_state->target == PIPE_TEXTURE_CUBE) {
 968       LLVMValueRef face, face_s, face_t;
 969       lp_build_cube_lookup(bld, s, t, r, &face, &face_s, &face_t);
 970       s = face_s; /* vec */
 971       t = face_t; /* vec */
 972       /* use 'r' to indicate cube face */
 973       r = lp_build_broadcast_scalar(&bld->int_coord_bld, face); /* vec */
 974
 975       /* recompute ddx, ddy using the new (s,t) face texcoords */
 976       face_ddx[0] = lp_build_ddx(&bld->coord_bld, s);
 977       face_ddx[1] = lp_build_ddx(&bld->coord_bld, t);
 978       face_ddx[2] = NULL;
 979       face_ddx[3] = NULL;
 980       face_ddy[0] = lp_build_ddy(&bld->coord_bld, s);
 981       face_ddy[1] = lp_build_ddy(&bld->coord_bld, t);
 982       face_ddy[2] = NULL;
 983       face_ddy[3] = NULL;
 984       ddx = face_ddx;
 985       ddy = face_ddy;
 986    }
 987
 988    /*
 989     * Compute the level of detail (float).
 990     */
 991    if (min_filter != mag_filter ||
 992        mip_filter != PIPE_TEX_MIPFILTER_NONE) {
 993       /* Need to compute lod either to choose mipmap levels or to
 994        * distinguish between minification/magnification with one mipmap level.
 995        */
 996       lp_build_lod_selector(bld, unit, ddx, ddy,
 997                             lod_bias, explicit_lod,
 998                             mip_filter,
 999                             &lod_ipart, &lod_fpart);
1000    } else {
1001       lod_ipart = i32t_zero;
1002    }
1003
1004    /*
1005     * Compute integer mipmap level(s) to fetch texels from: ilevel0, ilevel1
1006     */
1007    switch (mip_filter) {
1008    default:
1009       assert(0 && "bad mip_filter value in lp_build_sample_soa()");
1010       /* fall-through */
1011    case PIPE_TEX_MIPFILTER_NONE:
1012       /* always use mip level 0 */
1013       if (bld->static_state->target == PIPE_TEXTURE_CUBE) {
1014          /* XXX this is a work-around for an apparent bug in LLVM 2.7.
1015           * We should be able to set ilevel0 = const(0) but that causes
1016           * bad x86 code to be emitted.
1017           */
1018          assert(lod_ipart);
1019          lp_build_nearest_mip_level(bld, unit, lod_ipart, &ilevel0);
1020       }
1021       else {
1022          ilevel0 = i32t_zero;
1023       }
1024       break;
1025    case PIPE_TEX_MIPFILTER_NEAREST:
1026       assert(lod_ipart);
1027       lp_build_nearest_mip_level(bld, unit, lod_ipart, &ilevel0);
1028       break;
1029    case PIPE_TEX_MIPFILTER_LINEAR:
1030       assert(lod_ipart);
1031       assert(lod_fpart);
1032       lp_build_linear_mip_levels(bld, unit,
1033                                  lod_ipart, &lod_fpart,
1034                                  &ilevel0, &ilevel1);
1035       break;
1036    }
1037
1038    /*
1039     * Get/interpolate texture colors.
1040     */
1041
1042    for (chan = 0; chan < 4; ++chan) {
1043      texels[chan] = lp_build_alloca(builder, bld->texel_bld.vec_type, "");
1044      lp_build_name(texels[chan], "sampler%u_texel_%c_var", unit, "xyzw"[chan]);
1045    }
1046
1047    if (min_filter == mag_filter) {
1048       /* no need to distinquish between minification and magnification */
1049       lp_build_sample_mipmap(bld, unit,
1050                              min_filter, mip_filter,
1051                              s, t, r,
1052                              ilevel0, ilevel1, lod_fpart,
1053                              texels);
1054    }
1055    else {
1056       /* Emit conditional to choose min image filter or mag image filter
1057        * depending on the lod being > 0 or <= 0, respectively.
1058        */
1059       struct lp_build_if_state if_ctx;
1060       LLVMValueRef minify;
1061
1062       /* minify = lod >= 0.0 */
1063       minify = LLVMBuildICmp(builder, LLVMIntSGE,
1064                              lod_ipart, int_bld->zero, "");
1065
1066       lp_build_if(&if_ctx, builder, minify);
1067       {
1068          /* Use the minification filter */
1069          lp_build_sample_mipmap(bld, unit,
1070                                 min_filter, mip_filter,
1071                                 s, t, r,
1072                                 ilevel0, ilevel1, lod_fpart,
1073                                 texels);
1074       }
1075       lp_build_else(&if_ctx);
1076       {
1077          /* Use the magnification filter */
1078          lp_build_sample_mipmap(bld, unit,
1079                                 mag_filter, PIPE_TEX_MIPFILTER_NONE,
1080                                 s, t, r,
1081                                 i32t_zero, NULL, NULL,
1082                                 texels);
1083       }
1084       lp_build_endif(&if_ctx);
1085    }
1086
1087    for (chan = 0; chan < 4; ++chan) {
1088      colors_out[chan] = LLVMBuildLoad(builder, texels[chan], "");
1089      lp_build_name(colors_out[chan], "sampler%u_texel_%c", unit, "xyzw"[chan]);
1090    }
1091 }
1092
1093
1094 /**
1095  * Do shadow test/comparison.
1096  * \param p  the texcoord Z (aka R, aka P) component
1097  * \param texel  the texel to compare against (use the X channel)
1098  */
1099 static void
1100 lp_build_sample_compare(struct lp_build_sample_context *bld,
1101                         LLVMValueRef p,
1102                         LLVMValueRef texel[4])
1103 {
1104    struct lp_build_context *texel_bld = &bld->texel_bld;
1105    LLVMValueRef res;
1106    const unsigned chan = 0;
1107
1108    if (bld->static_state->compare_mode == PIPE_TEX_COMPARE_NONE)
1109       return;
1110
1111    /* debug code */
1112    if (0) {
1113       LLVMValueRef indx = lp_build_const_int32(0);
1114       LLVMValueRef coord = LLVMBuildExtractElement(bld->builder, p, indx, "");
1115       LLVMValueRef tex = LLVMBuildExtractElement(bld->builder,
1116                                                  texel[chan], indx, "");
1117       lp_build_printf(bld->builder, "shadow compare coord %f to texture %f\n",
1118                       coord, tex);
1119    }
1120
1121    /* result = (p FUNC texel) ? 1 : 0 */
1122    res = lp_build_cmp(texel_bld, bld->static_state->compare_func,
1123                       p, texel[chan]);
1124    res = lp_build_select(texel_bld, res, texel_bld->one, texel_bld->zero);
1125
1126    /* XXX returning result for default GL_DEPTH_TEXTURE_MODE = GL_LUMINANCE */
1127    texel[0] =
1128    texel[1] =
1129    texel[2] = res;
1130    texel[3] = texel_bld->one;
1131 }
1132
1133
1134 /**
1135  * Just set texels to white instead of actually sampling the texture.
1136  * For debugging.
1137  */
1138 void
1139 lp_build_sample_nop(struct lp_type type,
1140                     LLVMValueRef texel_out[4])
1141 {
1142    LLVMValueRef one = lp_build_one(type);
1143    unsigned chan;
1144
1145    for (chan = 0; chan < 4; chan++) {
1146       texel_out[chan] = one;
1147    }
1148 }
1149
1150
1151 /**
1152  * Build texture sampling code.
1153  * 'texel' will return a vector of four LLVMValueRefs corresponding to
1154  * R, G, B, A.
1155  * \param type  vector float type to use for coords, etc.
1156  * \param ddx  partial derivatives of (s,t,r,q) with respect to x
1157  * \param ddy  partial derivatives of (s,t,r,q) with respect to y
1158  */
1159 void
1160 lp_build_sample_soa(LLVMBuilderRef builder,
1161                     const struct lp_sampler_static_state *static_state,
1162                     struct lp_sampler_dynamic_state *dynamic_state,
1163                     struct lp_type type,
1164                     unsigned unit,
1165                     unsigned num_coords,
1166                     const LLVMValueRef *coords,
1167                     const LLVMValueRef ddx[4],
1168                     const LLVMValueRef ddy[4],
1169                     LLVMValueRef lod_bias, /* optional */
1170                     LLVMValueRef explicit_lod, /* optional */
1171                     LLVMValueRef texel_out[4])
1172 {
1173    unsigned dims = texture_dims(static_state->target);
1174    struct lp_build_sample_context bld;
1175    LLVMTypeRef i32t = LLVMInt32Type();
1176
1177    LLVMValueRef s;
1178    LLVMValueRef t;
1179    LLVMValueRef r;
1180    struct lp_type float_vec_type;
1181
1182    if (0) {
1183       enum pipe_format fmt = static_state->format;
1184       debug_printf("Sample from %s\n", util_format_name(fmt));
1185    }
1186
1187    assert(type.floating);
1188
1189    /* Setup our build context */
1190    memset(&bld, 0, sizeof bld);
1191    bld.builder = builder;
1192    bld.static_state = static_state;
1193    bld.dynamic_state = dynamic_state;
1194    bld.format_desc = util_format_description(static_state->format);
1195    bld.dims = dims;
1196
1197    bld.float_type = lp_type_float(32);
1198    bld.int_type = lp_type_int(32);
1199    bld.coord_type = type;
1200    bld.int_coord_type = lp_int_type(type);
1201    bld.float_size_type = lp_type_float(32);
1202    bld.float_size_type.length = dims > 1 ? 4 : 1;
1203    bld.int_size_type = lp_int_type(bld.float_size_type);
1204    bld.texel_type = type;
1205
1206    float_vec_type = lp_type_float_vec(32);
1207
1208    lp_build_context_init(&bld.float_bld, builder, bld.float_type);
1209    lp_build_context_init(&bld.float_vec_bld, builder, float_vec_type);
1210    lp_build_context_init(&bld.int_bld, builder, bld.int_type);
1211    lp_build_context_init(&bld.coord_bld, builder, bld.coord_type);
1212    lp_build_context_init(&bld.int_coord_bld, builder, bld.int_coord_type);
1213    lp_build_context_init(&bld.int_size_bld, builder, bld.int_size_type);
1214    lp_build_context_init(&bld.float_size_bld, builder, bld.float_size_type);
1215    lp_build_context_init(&bld.texel_bld, builder, bld.texel_type);
1216
1217    /* Get the dynamic state */
1218    bld.width = dynamic_state->width(dynamic_state, builder, unit);
1219    bld.height = dynamic_state->height(dynamic_state, builder, unit);
1220    bld.depth = dynamic_state->depth(dynamic_state, builder, unit);
1221    bld.row_stride_array = dynamic_state->row_stride(dynamic_state, builder, unit);
1222    bld.img_stride_array = dynamic_state->img_stride(dynamic_state, builder, unit);
1223    bld.data_array = dynamic_state->data_ptr(dynamic_state, builder, unit);
1224    /* Note that data_array is an array[level] of pointers to texture images */
1225
1226    s = coords[0];
1227    t = coords[1];
1228    r = coords[2];
1229
1230    /* width, height, depth as single int vector */
1231    if (dims <= 1) {
1232       bld.int_size = bld.width;
1233    }
1234    else {
1235       bld.int_size = LLVMBuildInsertElement(builder, bld.int_size_bld.undef,
1236                                             bld.width, LLVMConstInt(i32t, 0, 0), "");
1237       if (dims >= 2) {
1238          bld.int_size = LLVMBuildInsertElement(builder, bld.int_size,
1239                                                bld.height, LLVMConstInt(i32t, 1, 0), "");
1240          if (dims >= 3) {
1241             bld.int_size = LLVMBuildInsertElement(builder, bld.int_size,
1242                                                   bld.depth, LLVMConstInt(i32t, 2, 0), "");
1243          }
1244       }
1245    }
1246
1247    if (0) {
1248       /* For debug: no-op texture sampling */
1249       lp_build_sample_nop(bld.texel_type, texel_out);
1250    }
1251    else if (util_format_fits_8unorm(bld.format_desc) &&
1252             lp_is_simple_wrap_mode(static_state->wrap_s) &&
1253             lp_is_simple_wrap_mode(static_state->wrap_t)) {
1254       /* do sampling/filtering with fixed pt arithmetic */
1255       lp_build_sample_aos(&bld, unit, s, t, r, ddx, ddy,
1256                           lod_bias, explicit_lod,
1257                           texel_out);
1258    }
1259
1260    else {
1261       if ((gallivm_debug & GALLIVM_DEBUG_PERF) &&
1262           util_format_fits_8unorm(bld.format_desc)) {
1263          debug_printf("%s: using floating point linear filtering for %s\n",
1264                       __FUNCTION__, bld.format_desc->short_name);
1265          debug_printf("  min_img %d  mag_img %d  mip %d  wraps %d  wrapt %d\n",
1266                       static_state->min_img_filter,
1267                       static_state->mag_img_filter,
1268                       static_state->min_mip_filter,
1269                       static_state->wrap_s,
1270                       static_state->wrap_t);
1271       }
1272
1273       lp_build_sample_general(&bld, unit, s, t, r, ddx, ddy,
1274                               lod_bias, explicit_lod,
1275                               texel_out);
1276    }
1277
1278    lp_build_sample_compare(&bld, r, texel_out);
1279 }