lp_bld_sample_soa.c revision e1003336f0dcd9248c0127fbdc173522e35c5bdb
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 */
70static void
71lp_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 */
197static LLVMValueRef
198lp_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 */
229static void
230lp_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 */
440static LLVMValueRef
441lp_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 */
561static void
562lp_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 */
643static void
644lp_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 */
830static void
831lp_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 */
934static void
935lp_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 */
1099static void
1100lp_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 */
1138void
1139lp_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 */
1159void
1160lp_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}
1280