brw_blorp_blit.cpp revision 6cc9df331b4799715b31d7ec606ad09fa914e260
1/*
2 * Copyright © 2012 Intel Corporation
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
13 * Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21 * IN THE SOFTWARE.
22 */
23
24#include "main/teximage.h"
25#include "main/fbobject.h"
26
27#include "glsl/ralloc.h"
28
29#include "intel_fbo.h"
30
31#include "brw_blorp.h"
32#include "brw_context.h"
33#include "brw_eu.h"
34#include "brw_state.h"
35
36
37/**
38 * Helper function for handling mirror image blits.
39 *
40 * If coord0 > coord1, swap them and invert the "mirror" boolean.
41 */
42static inline void
43fixup_mirroring(bool &mirror, GLint &coord0, GLint &coord1)
44{
45   if (coord0 > coord1) {
46      mirror = !mirror;
47      GLint tmp = coord0;
48      coord0 = coord1;
49      coord1 = tmp;
50   }
51}
52
53
54/**
55 * Adjust {src,dst}_x{0,1} to account for clipping and scissoring of
56 * destination coordinates.
57 *
58 * Return true if there is still blitting to do, false if all pixels got
59 * rejected by the clip and/or scissor.
60 *
61 * For clarity, the nomenclature of this function assumes we are clipping and
62 * scissoring the X coordinate; the exact same logic applies for Y
63 * coordinates.
64 *
65 * Note: this function may also be used to account for clipping of source
66 * coordinates, by swapping the roles of src and dst.
67 */
68static inline bool
69clip_or_scissor(bool mirror, GLint &src_x0, GLint &src_x1, GLint &dst_x0,
70                GLint &dst_x1, GLint fb_xmin, GLint fb_xmax)
71{
72   /* If we are going to scissor everything away, stop. */
73   if (!(fb_xmin < fb_xmax &&
74         dst_x0 < fb_xmax &&
75         fb_xmin < dst_x1 &&
76         dst_x0 < dst_x1)) {
77      return false;
78   }
79
80   /* Clip the destination rectangle, and keep track of how many pixels we
81    * clipped off of the left and right sides of it.
82    */
83   GLint pixels_clipped_left = 0;
84   GLint pixels_clipped_right = 0;
85   if (dst_x0 < fb_xmin) {
86      pixels_clipped_left = fb_xmin - dst_x0;
87      dst_x0 = fb_xmin;
88   }
89   if (fb_xmax < dst_x1) {
90      pixels_clipped_right = dst_x1 - fb_xmax;
91      dst_x1 = fb_xmax;
92   }
93
94   /* If we are mirrored, then before applying pixels_clipped_{left,right} to
95    * the source coordinates, we need to flip them to account for the
96    * mirroring.
97    */
98   if (mirror) {
99      GLint tmp = pixels_clipped_left;
100      pixels_clipped_left = pixels_clipped_right;
101      pixels_clipped_right = tmp;
102   }
103
104   /* Adjust the source rectangle to remove the pixels corresponding to those
105    * that were clipped/scissored out of the destination rectangle.
106    */
107   src_x0 += pixels_clipped_left;
108   src_x1 -= pixels_clipped_right;
109
110   return true;
111}
112
113
114static struct intel_mipmap_tree *
115find_miptree(GLbitfield buffer_bit, struct gl_renderbuffer *rb)
116{
117   struct intel_renderbuffer *irb = intel_renderbuffer(rb);
118   struct intel_mipmap_tree *mt = irb->mt;
119   if (buffer_bit == GL_STENCIL_BUFFER_BIT && mt->stencil_mt)
120      mt = mt->stencil_mt;
121   return mt;
122}
123
124void
125brw_blorp_blit_miptrees(struct intel_context *intel,
126                        struct intel_mipmap_tree *src_mt,
127                        struct intel_mipmap_tree *dst_mt,
128                        int src_x0, int src_y0,
129                        int dst_x0, int dst_y0,
130                        int dst_x1, int dst_y1,
131                        bool mirror_x, bool mirror_y)
132{
133   brw_blorp_blit_params params(brw_context(&intel->ctx),
134                                src_mt, dst_mt,
135                                src_x0, src_y0,
136                                dst_x0, dst_y0,
137                                dst_x1, dst_y1,
138                                mirror_x, mirror_y);
139   brw_blorp_exec(intel, &params);
140}
141
142static void
143do_blorp_blit(struct intel_context *intel, GLbitfield buffer_bit,
144              struct gl_renderbuffer *src_rb, struct gl_renderbuffer *dst_rb,
145              GLint srcX0, GLint srcY0,
146              GLint dstX0, GLint dstY0, GLint dstX1, GLint dstY1,
147              bool mirror_x, bool mirror_y)
148{
149   struct gl_context *ctx = &intel->ctx;
150
151   /* Find source/dst miptrees */
152   struct intel_mipmap_tree *src_mt = find_miptree(buffer_bit, src_rb);
153   struct intel_mipmap_tree *dst_mt = find_miptree(buffer_bit, dst_rb);
154
155   /* Get ready to blit.  This includes depth resolving the src and dst
156    * buffers if necessary.
157    */
158   intel_renderbuffer_resolve_depth(intel, intel_renderbuffer(src_rb));
159   intel_renderbuffer_resolve_depth(intel, intel_renderbuffer(dst_rb));
160
161   /* Do the blit */
162   brw_blorp_blit_miptrees(intel, src_mt, dst_mt,
163                           srcX0, srcY0, dstX0, dstY0, dstX1, dstY1,
164                           mirror_x, mirror_y);
165
166   /* Mark the dst buffer as needing a HiZ resolve if necessary. */
167   intel_renderbuffer_set_needs_hiz_resolve(intel_renderbuffer(dst_rb));
168}
169
170
171static bool
172formats_match(GLbitfield buffer_bit, struct gl_renderbuffer *src_rb,
173              struct gl_renderbuffer *dst_rb)
174{
175   /* Note: don't just check gl_renderbuffer::Format, because in some cases
176    * multiple gl_formats resolve to the same native type in the miptree (for
177    * example MESA_FORMAT_X8_Z24 and MESA_FORMAT_S8_Z24), and we can blit
178    * between those formats.
179    */
180   return find_miptree(buffer_bit, src_rb)->format ==
181      find_miptree(buffer_bit, dst_rb)->format;
182}
183
184
185static bool
186try_blorp_blit(struct intel_context *intel,
187               GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
188               GLint dstX0, GLint dstY0, GLint dstX1, GLint dstY1,
189               GLenum filter, GLbitfield buffer_bit)
190{
191   struct gl_context *ctx = &intel->ctx;
192
193   /* Sync up the state of window system buffers.  We need to do this before
194    * we go looking for the buffers.
195    */
196   intel_prepare_render(intel);
197
198   const struct gl_framebuffer *read_fb = ctx->ReadBuffer;
199   const struct gl_framebuffer *draw_fb = ctx->DrawBuffer;
200
201   /* Detect if the blit needs to be mirrored */
202   bool mirror_x = false, mirror_y = false;
203   fixup_mirroring(mirror_x, srcX0, srcX1);
204   fixup_mirroring(mirror_x, dstX0, dstX1);
205   fixup_mirroring(mirror_y, srcY0, srcY1);
206   fixup_mirroring(mirror_y, dstY0, dstY1);
207
208   /* Make sure width and height match */
209   if (srcX1 - srcX0 != dstX1 - dstX0) return false;
210   if (srcY1 - srcY0 != dstY1 - dstY0) return false;
211
212   /* If the destination rectangle needs to be clipped or scissored, do so.
213    */
214   if (!(clip_or_scissor(mirror_x, srcX0, srcX1, dstX0, dstX1,
215                         draw_fb->_Xmin, draw_fb->_Xmax) &&
216         clip_or_scissor(mirror_y, srcY0, srcY1, dstY0, dstY1,
217                         draw_fb->_Ymin, draw_fb->_Ymax))) {
218      /* Everything got clipped/scissored away, so the blit was successful. */
219      return true;
220   }
221
222   /* If the source rectangle needs to be clipped or scissored, do so. */
223   if (!(clip_or_scissor(mirror_x, dstX0, dstX1, srcX0, srcX1,
224                         0, read_fb->Width) &&
225         clip_or_scissor(mirror_y, dstY0, dstY1, srcY0, srcY1,
226                         0, read_fb->Height))) {
227      /* Everything got clipped/scissored away, so the blit was successful. */
228      return true;
229   }
230
231   /* Account for the fact that in the system framebuffer, the origin is at
232    * the lower left.
233    */
234   if (_mesa_is_winsys_fbo(read_fb)) {
235      GLint tmp = read_fb->Height - srcY0;
236      srcY0 = read_fb->Height - srcY1;
237      srcY1 = tmp;
238      mirror_y = !mirror_y;
239   }
240   if (_mesa_is_winsys_fbo(draw_fb)) {
241      GLint tmp = draw_fb->Height - dstY0;
242      dstY0 = draw_fb->Height - dstY1;
243      dstY1 = tmp;
244      mirror_y = !mirror_y;
245   }
246
247   /* Find buffers */
248   struct gl_renderbuffer *src_rb;
249   struct gl_renderbuffer *dst_rb;
250   switch (buffer_bit) {
251   case GL_COLOR_BUFFER_BIT:
252      src_rb = read_fb->_ColorReadBuffer;
253      for (unsigned i = 0; i < ctx->DrawBuffer->_NumColorDrawBuffers; ++i) {
254         dst_rb = ctx->DrawBuffer->_ColorDrawBuffers[i];
255         if (dst_rb && !formats_match(buffer_bit, src_rb, dst_rb))
256            return false;
257      }
258      for (unsigned i = 0; i < ctx->DrawBuffer->_NumColorDrawBuffers; ++i) {
259         dst_rb = ctx->DrawBuffer->_ColorDrawBuffers[i];
260         do_blorp_blit(intel, buffer_bit, src_rb, dst_rb, srcX0, srcY0,
261                       dstX0, dstY0, dstX1, dstY1, mirror_x, mirror_y);
262      }
263      break;
264   case GL_DEPTH_BUFFER_BIT:
265      src_rb = read_fb->Attachment[BUFFER_DEPTH].Renderbuffer;
266      dst_rb = draw_fb->Attachment[BUFFER_DEPTH].Renderbuffer;
267      if (!formats_match(buffer_bit, src_rb, dst_rb))
268         return false;
269      do_blorp_blit(intel, buffer_bit, src_rb, dst_rb, srcX0, srcY0,
270                    dstX0, dstY0, dstX1, dstY1, mirror_x, mirror_y);
271      break;
272   case GL_STENCIL_BUFFER_BIT:
273      src_rb = read_fb->Attachment[BUFFER_STENCIL].Renderbuffer;
274      dst_rb = draw_fb->Attachment[BUFFER_STENCIL].Renderbuffer;
275      if (!formats_match(buffer_bit, src_rb, dst_rb))
276         return false;
277      do_blorp_blit(intel, buffer_bit, src_rb, dst_rb, srcX0, srcY0,
278                    dstX0, dstY0, dstX1, dstY1, mirror_x, mirror_y);
279      break;
280   default:
281      assert(false);
282   }
283
284   return true;
285}
286
287GLbitfield
288brw_blorp_framebuffer(struct intel_context *intel,
289                      GLint srcX0, GLint srcY0, GLint srcX1, GLint srcY1,
290                      GLint dstX0, GLint dstY0, GLint dstX1, GLint dstY1,
291                      GLbitfield mask, GLenum filter)
292{
293   /* BLORP is not supported before Gen6. */
294   if (intel->gen < 6)
295      return mask;
296
297   static GLbitfield buffer_bits[] = {
298      GL_COLOR_BUFFER_BIT,
299      GL_DEPTH_BUFFER_BIT,
300      GL_STENCIL_BUFFER_BIT,
301   };
302
303   for (unsigned int i = 0; i < ARRAY_SIZE(buffer_bits); ++i) {
304      if ((mask & buffer_bits[i]) &&
305       try_blorp_blit(intel,
306                      srcX0, srcY0, srcX1, srcY1,
307                      dstX0, dstY0, dstX1, dstY1,
308                      filter, buffer_bits[i])) {
309         mask &= ~buffer_bits[i];
310      }
311   }
312
313   return mask;
314}
315
316
317/**
318 * Enum to specify the order of arguments in a sampler message
319 */
320enum sampler_message_arg
321{
322   SAMPLER_MESSAGE_ARG_U_FLOAT,
323   SAMPLER_MESSAGE_ARG_V_FLOAT,
324   SAMPLER_MESSAGE_ARG_U_INT,
325   SAMPLER_MESSAGE_ARG_V_INT,
326   SAMPLER_MESSAGE_ARG_SI_INT,
327   SAMPLER_MESSAGE_ARG_MCS_INT,
328   SAMPLER_MESSAGE_ARG_ZERO_INT,
329};
330
331/**
332 * Generator for WM programs used in BLORP blits.
333 *
334 * The bulk of the work done by the WM program is to wrap and unwrap the
335 * coordinate transformations used by the hardware to store surfaces in
336 * memory.  The hardware transforms a pixel location (X, Y, S) (where S is the
337 * sample index for a multisampled surface) to a memory offset by the
338 * following formulas:
339 *
340 *   offset = tile(tiling_format, encode_msaa(num_samples, layout, X, Y, S))
341 *   (X, Y, S) = decode_msaa(num_samples, layout, detile(tiling_format, offset))
342 *
343 * For a single-sampled surface, or for a multisampled surface using
344 * INTEL_MSAA_LAYOUT_UMS, encode_msaa() and decode_msaa are the identity
345 * function:
346 *
347 *   encode_msaa(1, NONE, X, Y, 0) = (X, Y, 0)
348 *   decode_msaa(1, NONE, X, Y, 0) = (X, Y, 0)
349 *   encode_msaa(n, UMS, X, Y, S) = (X, Y, S)
350 *   decode_msaa(n, UMS, X, Y, S) = (X, Y, S)
351 *
352 * For a 4x multisampled surface using INTEL_MSAA_LAYOUT_IMS, encode_msaa()
353 * embeds the sample number into bit 1 of the X and Y coordinates:
354 *
355 *   encode_msaa(4, IMS, X, Y, S) = (X', Y', 0)
356 *     where X' = (X & ~0b1) << 1 | (S & 0b1) << 1 | (X & 0b1)
357 *           Y' = (Y & ~0b1 ) << 1 | (S & 0b10) | (Y & 0b1)
358 *   decode_msaa(4, IMS, X, Y, 0) = (X', Y', S)
359 *     where X' = (X & ~0b11) >> 1 | (X & 0b1)
360 *           Y' = (Y & ~0b11) >> 1 | (Y & 0b1)
361 *           S = (Y & 0b10) | (X & 0b10) >> 1
362 *
363 * For an 8x multisampled surface using INTEL_MSAA_LAYOUT_IMS, encode_msaa()
364 * embeds the sample number into bits 1 and 2 of the X coordinate and bit 1 of
365 * the Y coordinate:
366 *
367 *   encode_msaa(8, IMS, X, Y, S) = (X', Y', 0)
368 *     where X' = (X & ~0b1) << 2 | (S & 0b100) | (S & 0b1) << 1 | (X & 0b1)
369 *           Y' = (Y & ~0b1) << 1 | (S & 0b10) | (Y & 0b1)
370 *   decode_msaa(8, IMS, X, Y, 0) = (X', Y', S)
371 *     where X' = (X & ~0b111) >> 2 | (X & 0b1)
372 *           Y' = (Y & ~0b11) >> 1 | (Y & 0b1)
373 *           S = (X & 0b100) | (Y & 0b10) | (X & 0b10) >> 1
374 *
375 * For X tiling, tile() combines together the low-order bits of the X and Y
376 * coordinates in the pattern 0byyyxxxxxxxxx, creating 4k tiles that are 512
377 * bytes wide and 8 rows high:
378 *
379 *   tile(x_tiled, X, Y, S) = A
380 *     where A = tile_num << 12 | offset
381 *           tile_num = (Y' >> 3) * tile_pitch + (X' >> 9)
382 *           offset = (Y' & 0b111) << 9
383 *                    | (X & 0b111111111)
384 *           X' = X * cpp
385 *           Y' = Y + S * qpitch
386 *   detile(x_tiled, A) = (X, Y, S)
387 *     where X = X' / cpp
388 *           Y = Y' % qpitch
389 *           S = Y' / qpitch
390 *           Y' = (tile_num / tile_pitch) << 3
391 *                | (A & 0b111000000000) >> 9
392 *           X' = (tile_num % tile_pitch) << 9
393 *                | (A & 0b111111111)
394 *
395 * (In all tiling formulas, cpp is the number of bytes occupied by a single
396 * sample ("chars per pixel"), tile_pitch is the number of 4k tiles required
397 * to fill the width of the surface, and qpitch is the spacing (in rows)
398 * between array slices).
399 *
400 * For Y tiling, tile() combines together the low-order bits of the X and Y
401 * coordinates in the pattern 0bxxxyyyyyxxxx, creating 4k tiles that are 128
402 * bytes wide and 32 rows high:
403 *
404 *   tile(y_tiled, X, Y, S) = A
405 *     where A = tile_num << 12 | offset
406 *           tile_num = (Y' >> 5) * tile_pitch + (X' >> 7)
407 *           offset = (X' & 0b1110000) << 5
408 *                    | (Y' & 0b11111) << 4
409 *                    | (X' & 0b1111)
410 *           X' = X * cpp
411 *           Y' = Y + S * qpitch
412 *   detile(y_tiled, A) = (X, Y, S)
413 *     where X = X' / cpp
414 *           Y = Y' % qpitch
415 *           S = Y' / qpitch
416 *           Y' = (tile_num / tile_pitch) << 5
417 *                | (A & 0b111110000) >> 4
418 *           X' = (tile_num % tile_pitch) << 7
419 *                | (A & 0b111000000000) >> 5
420 *                | (A & 0b1111)
421 *
422 * For W tiling, tile() combines together the low-order bits of the X and Y
423 * coordinates in the pattern 0bxxxyyyyxyxyx, creating 4k tiles that are 64
424 * bytes wide and 64 rows high (note that W tiling is only used for stencil
425 * buffers, which always have cpp = 1 and S=0):
426 *
427 *   tile(w_tiled, X, Y, S) = A
428 *     where A = tile_num << 12 | offset
429 *           tile_num = (Y' >> 6) * tile_pitch + (X' >> 6)
430 *           offset = (X' & 0b111000) << 6
431 *                    | (Y' & 0b111100) << 3
432 *                    | (X' & 0b100) << 2
433 *                    | (Y' & 0b10) << 2
434 *                    | (X' & 0b10) << 1
435 *                    | (Y' & 0b1) << 1
436 *                    | (X' & 0b1)
437 *           X' = X * cpp = X
438 *           Y' = Y + S * qpitch
439 *   detile(w_tiled, A) = (X, Y, S)
440 *     where X = X' / cpp = X'
441 *           Y = Y' % qpitch = Y'
442 *           S = Y / qpitch = 0
443 *           Y' = (tile_num / tile_pitch) << 6
444 *                | (A & 0b111100000) >> 3
445 *                | (A & 0b1000) >> 2
446 *                | (A & 0b10) >> 1
447 *           X' = (tile_num % tile_pitch) << 6
448 *                | (A & 0b111000000000) >> 6
449 *                | (A & 0b10000) >> 2
450 *                | (A & 0b100) >> 1
451 *                | (A & 0b1)
452 *
453 * Finally, for a non-tiled surface, tile() simply combines together the X and
454 * Y coordinates in the natural way:
455 *
456 *   tile(untiled, X, Y, S) = A
457 *     where A = Y * pitch + X'
458 *           X' = X * cpp
459 *           Y' = Y + S * qpitch
460 *   detile(untiled, A) = (X, Y, S)
461 *     where X = X' / cpp
462 *           Y = Y' % qpitch
463 *           S = Y' / qpitch
464 *           X' = A % pitch
465 *           Y' = A / pitch
466 *
467 * (In these formulas, pitch is the number of bytes occupied by a single row
468 * of samples).
469 */
470class brw_blorp_blit_program
471{
472public:
473   brw_blorp_blit_program(struct brw_context *brw,
474                          const brw_blorp_blit_prog_key *key);
475   ~brw_blorp_blit_program();
476
477   const GLuint *compile(struct brw_context *brw, GLuint *program_size);
478
479   brw_blorp_prog_data prog_data;
480
481private:
482   void alloc_regs();
483   void alloc_push_const_regs(int base_reg);
484   void compute_frag_coords();
485   void translate_tiling(bool old_tiled_w, bool new_tiled_w);
486   void encode_msaa(unsigned num_samples, intel_msaa_layout layout);
487   void decode_msaa(unsigned num_samples, intel_msaa_layout layout);
488   void kill_if_outside_dst_rect();
489   void translate_dst_to_src();
490   void single_to_blend();
491   void manual_blend(unsigned num_samples);
492   void sample(struct brw_reg dst);
493   void texel_fetch(struct brw_reg dst);
494   void mcs_fetch();
495   void expand_to_32_bits(struct brw_reg src, struct brw_reg dst);
496   void texture_lookup(struct brw_reg dst, GLuint msg_type,
497                       const sampler_message_arg *args, int num_args);
498   void render_target_write();
499
500   /**
501    * Base-2 logarithm of the maximum number of samples that can be blended.
502    */
503   static const unsigned LOG2_MAX_BLEND_SAMPLES = 3;
504
505   void *mem_ctx;
506   struct brw_context *brw;
507   const brw_blorp_blit_prog_key *key;
508   struct brw_compile func;
509
510   /* Thread dispatch header */
511   struct brw_reg R0;
512
513   /* Pixel X/Y coordinates (always in R1). */
514   struct brw_reg R1;
515
516   /* Push constants */
517   struct brw_reg dst_x0;
518   struct brw_reg dst_x1;
519   struct brw_reg dst_y0;
520   struct brw_reg dst_y1;
521   struct {
522      struct brw_reg multiplier;
523      struct brw_reg offset;
524   } x_transform, y_transform;
525
526   /* Data read from texture (4 vec16's per array element) */
527   struct brw_reg texture_data[LOG2_MAX_BLEND_SAMPLES + 1];
528
529   /* Auxiliary storage for the contents of the MCS surface.
530    *
531    * Since the sampler always returns 8 registers worth of data, this is 8
532    * registers wide, even though we only use the first 2 registers of it.
533    */
534   struct brw_reg mcs_data;
535
536   /* X coordinates.  We have two of them so that we can perform coordinate
537    * transformations easily.
538    */
539   struct brw_reg x_coords[2];
540
541   /* Y coordinates.  We have two of them so that we can perform coordinate
542    * transformations easily.
543    */
544   struct brw_reg y_coords[2];
545
546   /* Which element of x_coords and y_coords is currently in use.
547    */
548   int xy_coord_index;
549
550   /* True if, at the point in the program currently being compiled, the
551    * sample index is known to be zero.
552    */
553   bool s_is_zero;
554
555   /* Register storing the sample index when s_is_zero is false. */
556   struct brw_reg sample_index;
557
558   /* Temporaries */
559   struct brw_reg t1;
560   struct brw_reg t2;
561
562   /* MRF used for sampling and render target writes */
563   GLuint base_mrf;
564};
565
566brw_blorp_blit_program::brw_blorp_blit_program(
567      struct brw_context *brw,
568      const brw_blorp_blit_prog_key *key)
569   : mem_ctx(ralloc_context(NULL)),
570     brw(brw),
571     key(key)
572{
573   brw_init_compile(brw, &func, mem_ctx);
574}
575
576brw_blorp_blit_program::~brw_blorp_blit_program()
577{
578   ralloc_free(mem_ctx);
579}
580
581const GLuint *
582brw_blorp_blit_program::compile(struct brw_context *brw,
583                                GLuint *program_size)
584{
585   /* Sanity checks */
586   if (key->dst_tiled_w && key->rt_samples > 0) {
587      /* If the destination image is W tiled and multisampled, then the thread
588       * must be dispatched once per sample, not once per pixel.  This is
589       * necessary because after conversion between W and Y tiling, there's no
590       * guarantee that all samples corresponding to a single pixel will still
591       * be together.
592       */
593      assert(key->persample_msaa_dispatch);
594   }
595
596   if (key->blend) {
597      /* We are blending, which means we won't have an opportunity to
598       * translate the tiling and sample count for the texture surface.  So
599       * the surface state for the texture must be configured with the correct
600       * tiling and sample count.
601       */
602      assert(!key->src_tiled_w);
603      assert(key->tex_samples == key->src_samples);
604      assert(key->tex_layout == key->src_layout);
605      assert(key->tex_samples > 0);
606   }
607
608   if (key->persample_msaa_dispatch) {
609      /* It only makes sense to do persample dispatch if the render target is
610       * configured as multisampled.
611       */
612      assert(key->rt_samples > 0);
613   }
614
615   /* Make sure layout is consistent with sample count */
616   assert((key->tex_layout == INTEL_MSAA_LAYOUT_NONE) ==
617          (key->tex_samples == 0));
618   assert((key->rt_layout == INTEL_MSAA_LAYOUT_NONE) ==
619          (key->rt_samples == 0));
620   assert((key->src_layout == INTEL_MSAA_LAYOUT_NONE) ==
621          (key->src_samples == 0));
622   assert((key->dst_layout == INTEL_MSAA_LAYOUT_NONE) ==
623          (key->dst_samples == 0));
624
625   /* Set up prog_data */
626   memset(&prog_data, 0, sizeof(prog_data));
627   prog_data.persample_msaa_dispatch = key->persample_msaa_dispatch;
628
629   brw_set_compression_control(&func, BRW_COMPRESSION_NONE);
630
631   alloc_regs();
632   compute_frag_coords();
633
634   /* Render target and texture hardware don't support W tiling. */
635   const bool rt_tiled_w = false;
636   const bool tex_tiled_w = false;
637
638   /* The address that data will be written to is determined by the
639    * coordinates supplied to the WM thread and the tiling and sample count of
640    * the render target, according to the formula:
641    *
642    * (X, Y, S) = decode_msaa(rt_samples, detile(rt_tiling, offset))
643    *
644    * If the actual tiling and sample count of the destination surface are not
645    * the same as the configuration of the render target, then these
646    * coordinates are wrong and we have to adjust them to compensate for the
647    * difference.
648    */
649   if (rt_tiled_w != key->dst_tiled_w ||
650       key->rt_samples != key->dst_samples ||
651       key->rt_layout != key->dst_layout) {
652      encode_msaa(key->rt_samples, key->rt_layout);
653      /* Now (X, Y, S) = detile(rt_tiling, offset) */
654      translate_tiling(rt_tiled_w, key->dst_tiled_w);
655      /* Now (X, Y, S) = detile(dst_tiling, offset) */
656      decode_msaa(key->dst_samples, key->dst_layout);
657   }
658
659   /* Now (X, Y, S) = decode_msaa(dst_samples, detile(dst_tiling, offset)).
660    *
661    * That is: X, Y and S now contain the true coordinates and sample index of
662    * the data that the WM thread should output.
663    *
664    * If we need to kill pixels that are outside the destination rectangle,
665    * now is the time to do it.
666    */
667
668   if (key->use_kill)
669      kill_if_outside_dst_rect();
670
671   /* Next, apply a translation to obtain coordinates in the source image. */
672   translate_dst_to_src();
673
674   /* If the source image is not multisampled, then we want to fetch sample
675    * number 0, because that's the only sample there is.
676    */
677   if (key->src_samples == 0)
678      s_is_zero = true;
679
680   /* X, Y, and S are now the coordinates of the pixel in the source image
681    * that we want to texture from.  Exception: if we are blending, then S is
682    * irrelevant, because we are going to fetch all samples.
683    */
684   if (key->blend) {
685      if (brw->intel.gen == 6) {
686         /* Gen6 hardware an automatically blend using the SAMPLE message */
687         single_to_blend();
688         sample(texture_data[0]);
689      } else {
690         /* Gen7+ hardware doesn't automaticaly blend. */
691         manual_blend(key->src_samples);
692      }
693   } else {
694      /* We aren't blending, which means we just want to fetch a single sample
695       * from the source surface.  The address that we want to fetch from is
696       * related to the X, Y and S values according to the formula:
697       *
698       * (X, Y, S) = decode_msaa(src_samples, detile(src_tiling, offset)).
699       *
700       * If the actual tiling and sample count of the source surface are not
701       * the same as the configuration of the texture, then we need to adjust
702       * the coordinates to compensate for the difference.
703       */
704      if (tex_tiled_w != key->src_tiled_w ||
705          key->tex_samples != key->src_samples ||
706          key->tex_layout != key->src_layout) {
707         encode_msaa(key->src_samples, key->src_layout);
708         /* Now (X, Y, S) = detile(src_tiling, offset) */
709         translate_tiling(key->src_tiled_w, tex_tiled_w);
710         /* Now (X, Y, S) = detile(tex_tiling, offset) */
711         decode_msaa(key->tex_samples, key->tex_layout);
712      }
713
714      /* Now (X, Y, S) = decode_msaa(tex_samples, detile(tex_tiling, offset)).
715       *
716       * In other words: X, Y, and S now contain values which, when passed to
717       * the texturing unit, will cause data to be read from the correct
718       * memory location.  So we can fetch the texel now.
719       */
720      if (key->tex_layout == INTEL_MSAA_LAYOUT_CMS)
721         mcs_fetch();
722      texel_fetch(texture_data[0]);
723   }
724
725   /* Finally, write the fetched (or blended) value to the render target and
726    * terminate the thread.
727    */
728   render_target_write();
729   return brw_get_program(&func, program_size);
730}
731
732void
733brw_blorp_blit_program::alloc_push_const_regs(int base_reg)
734{
735#define CONST_LOC(name) offsetof(brw_blorp_wm_push_constants, name)
736#define ALLOC_REG(name) \
737   this->name = \
738      brw_uw1_reg(BRW_GENERAL_REGISTER_FILE, base_reg, CONST_LOC(name) / 2)
739
740   ALLOC_REG(dst_x0);
741   ALLOC_REG(dst_x1);
742   ALLOC_REG(dst_y0);
743   ALLOC_REG(dst_y1);
744   ALLOC_REG(x_transform.multiplier);
745   ALLOC_REG(x_transform.offset);
746   ALLOC_REG(y_transform.multiplier);
747   ALLOC_REG(y_transform.offset);
748#undef CONST_LOC
749#undef ALLOC_REG
750}
751
752void
753brw_blorp_blit_program::alloc_regs()
754{
755   int reg = 0;
756   this->R0 = retype(brw_vec8_grf(reg++, 0), BRW_REGISTER_TYPE_UW);
757   this->R1 = retype(brw_vec8_grf(reg++, 0), BRW_REGISTER_TYPE_UW);
758   prog_data.first_curbe_grf = reg;
759   alloc_push_const_regs(reg);
760   reg += BRW_BLORP_NUM_PUSH_CONST_REGS;
761   for (unsigned i = 0; i < ARRAY_SIZE(texture_data); ++i) {
762      this->texture_data[i] =
763         retype(vec16(brw_vec8_grf(reg, 0)), key->texture_data_type);
764      reg += 8;
765   }
766   this->mcs_data =
767      retype(brw_vec8_grf(reg, 0), BRW_REGISTER_TYPE_UD); reg += 8;
768   for (int i = 0; i < 2; ++i) {
769      this->x_coords[i]
770         = vec16(retype(brw_vec8_grf(reg++, 0), BRW_REGISTER_TYPE_UW));
771      this->y_coords[i]
772         = vec16(retype(brw_vec8_grf(reg++, 0), BRW_REGISTER_TYPE_UW));
773   }
774   this->xy_coord_index = 0;
775   this->sample_index
776      = vec16(retype(brw_vec8_grf(reg++, 0), BRW_REGISTER_TYPE_UW));
777   this->t1 = vec16(retype(brw_vec8_grf(reg++, 0), BRW_REGISTER_TYPE_UW));
778   this->t2 = vec16(retype(brw_vec8_grf(reg++, 0), BRW_REGISTER_TYPE_UW));
779
780   /* Make sure we didn't run out of registers */
781   assert(reg <= GEN7_MRF_HACK_START);
782
783   int mrf = 2;
784   this->base_mrf = mrf;
785}
786
787/* In the code that follows, X and Y can be used to quickly refer to the
788 * active elements of x_coords and y_coords, and Xp and Yp ("X prime" and "Y
789 * prime") to the inactive elements.
790 *
791 * S can be used to quickly refer to sample_index.
792 */
793#define X x_coords[xy_coord_index]
794#define Y y_coords[xy_coord_index]
795#define Xp x_coords[!xy_coord_index]
796#define Yp y_coords[!xy_coord_index]
797#define S sample_index
798
799/* Quickly swap the roles of (X, Y) and (Xp, Yp).  Saves us from having to do
800 * MOVs to transfor (Xp, Yp) to (X, Y) after a coordinate transformation.
801 */
802#define SWAP_XY_AND_XPYP() xy_coord_index = !xy_coord_index;
803
804/**
805 * Emit code to compute the X and Y coordinates of the pixels being rendered
806 * by this WM invocation.
807 *
808 * Assuming the render target is set up for Y tiling, these (X, Y) values are
809 * related to the address offset where outputs will be written by the formula:
810 *
811 *   (X, Y, S) = decode_msaa(detile(offset)).
812 *
813 * (See brw_blorp_blit_program).
814 */
815void
816brw_blorp_blit_program::compute_frag_coords()
817{
818   /* R1.2[15:0] = X coordinate of upper left pixel of subspan 0 (pixel 0)
819    * R1.3[15:0] = X coordinate of upper left pixel of subspan 1 (pixel 4)
820    * R1.4[15:0] = X coordinate of upper left pixel of subspan 2 (pixel 8)
821    * R1.5[15:0] = X coordinate of upper left pixel of subspan 3 (pixel 12)
822    *
823    * Pixels within a subspan are laid out in this arrangement:
824    * 0 1
825    * 2 3
826    *
827    * So, to compute the coordinates of each pixel, we need to read every 2nd
828    * 16-bit value (vstride=2) from R1, starting at the 4th 16-bit value
829    * (suboffset=4), and duplicate each value 4 times (hstride=0, width=4).
830    * In other words, the data we want to access is R1.4<2;4,0>UW.
831    *
832    * Then, we need to add the repeating sequence (0, 1, 0, 1, ...) to the
833    * result, since pixels n+1 and n+3 are in the right half of the subspan.
834    */
835   brw_ADD(&func, X, stride(suboffset(R1, 4), 2, 4, 0), brw_imm_v(0x10101010));
836
837   /* Similarly, Y coordinates for subspans come from R1.2[31:16] through
838    * R1.5[31:16], so to get pixel Y coordinates we need to start at the 5th
839    * 16-bit value instead of the 4th (R1.5<2;4,0>UW instead of
840    * R1.4<2;4,0>UW).
841    *
842    * And we need to add the repeating sequence (0, 0, 1, 1, ...), since
843    * pixels n+2 and n+3 are in the bottom half of the subspan.
844    */
845   brw_ADD(&func, Y, stride(suboffset(R1, 5), 2, 4, 0), brw_imm_v(0x11001100));
846
847   if (key->persample_msaa_dispatch) {
848      switch (key->rt_samples) {
849      case 4:
850         /* The WM will be run in MSDISPMODE_PERSAMPLE with num_samples == 4.
851          * Therefore, subspan 0 will represent sample 0, subspan 1 will
852          * represent sample 1, and so on.
853          *
854          * So we need to populate S with the sequence (0, 0, 0, 0, 1, 1, 1,
855          * 1, 2, 2, 2, 2, 3, 3, 3, 3).  The easiest way to do this is to
856          * populate a temporary variable with the sequence (0, 1, 2, 3), and
857          * then copy from it using vstride=1, width=4, hstride=0.
858          */
859         brw_MOV(&func, t1, brw_imm_v(0x3210));
860         brw_MOV(&func, S, stride(t1, 1, 4, 0));
861         break;
862      case 8: {
863         /* The WM will be run in MSDISPMODE_PERSAMPLE with num_samples == 8.
864          * Therefore, subspan 0 will represent sample N (where N is 0 or 4),
865          * subspan 1 will represent sample 1, and so on.  We can find the
866          * value of N by looking at R0.0 bits 7:6 ("Starting Sample Pair
867          * Index") and multiplying by two (since samples are always delivered
868          * in pairs).  That is, we compute 2*((R0.0 & 0xc0) >> 6) == (R0.0 &
869          * 0xc0) >> 5.
870          *
871          * Then we need to add N to the sequence (0, 0, 0, 0, 1, 1, 1, 1, 2,
872          * 2, 2, 2, 3, 3, 3, 3), which we compute by populating a temporary
873          * variable with the sequence (0, 1, 2, 3), and then reading from it
874          * using vstride=1, width=4, hstride=0.
875          */
876         struct brw_reg t1_ud1 = vec1(retype(t1, BRW_REGISTER_TYPE_UD));
877         struct brw_reg r0_ud1 = vec1(retype(R0, BRW_REGISTER_TYPE_UD));
878         brw_AND(&func, t1_ud1, r0_ud1, brw_imm_ud(0xc0));
879         brw_SHR(&func, t1_ud1, t1_ud1, brw_imm_ud(5));
880         brw_MOV(&func, t2, brw_imm_v(0x3210));
881         brw_ADD(&func, S, retype(t1_ud1, BRW_REGISTER_TYPE_UW),
882                 stride(t2, 1, 4, 0));
883         break;
884      }
885      default:
886         assert(!"Unrecognized sample count in "
887                "brw_blorp_blit_program::compute_frag_coords()");
888         break;
889      }
890      s_is_zero = false;
891   } else {
892      /* Either the destination surface is single-sampled, or the WM will be
893       * run in MSDISPMODE_PERPIXEL (which causes a single fragment dispatch
894       * per pixel).  In either case, it's not meaningful to compute a sample
895       * value.  Just set it to 0.
896       */
897      s_is_zero = true;
898   }
899}
900
901/**
902 * Emit code to compensate for the difference between Y and W tiling.
903 *
904 * This code modifies the X and Y coordinates according to the formula:
905 *
906 *   (X', Y', S') = detile(new_tiling, tile(old_tiling, X, Y, S))
907 *
908 * (See brw_blorp_blit_program).
909 *
910 * It can only translate between W and Y tiling, so new_tiling and old_tiling
911 * are booleans where true represents W tiling and false represents Y tiling.
912 */
913void
914brw_blorp_blit_program::translate_tiling(bool old_tiled_w, bool new_tiled_w)
915{
916   if (old_tiled_w == new_tiled_w)
917      return;
918
919   /* In the code that follows, we can safely assume that S = 0, because W
920    * tiling formats always use IMS layout.
921    */
922   assert(s_is_zero);
923
924   if (new_tiled_w) {
925      /* Given X and Y coordinates that describe an address using Y tiling,
926       * translate to the X and Y coordinates that describe the same address
927       * using W tiling.
928       *
929       * If we break down the low order bits of X and Y, using a
930       * single letter to represent each low-order bit:
931       *
932       *   X = A << 7 | 0bBCDEFGH
933       *   Y = J << 5 | 0bKLMNP                                       (1)
934       *
935       * Then we can apply the Y tiling formula to see the memory offset being
936       * addressed:
937       *
938       *   offset = (J * tile_pitch + A) << 12 | 0bBCDKLMNPEFGH       (2)
939       *
940       * If we apply the W detiling formula to this memory location, that the
941       * corresponding X' and Y' coordinates are:
942       *
943       *   X' = A << 6 | 0bBCDPFH                                     (3)
944       *   Y' = J << 6 | 0bKLMNEG
945       *
946       * Combining (1) and (3), we see that to transform (X, Y) to (X', Y'),
947       * we need to make the following computation:
948       *
949       *   X' = (X & ~0b1011) >> 1 | (Y & 0b1) << 2 | X & 0b1         (4)
950       *   Y' = (Y & ~0b1) << 1 | (X & 0b1000) >> 2 | (X & 0b10) >> 1
951       */
952      brw_AND(&func, t1, X, brw_imm_uw(0xfff4)); /* X & ~0b1011 */
953      brw_SHR(&func, t1, t1, brw_imm_uw(1)); /* (X & ~0b1011) >> 1 */
954      brw_AND(&func, t2, Y, brw_imm_uw(1)); /* Y & 0b1 */
955      brw_SHL(&func, t2, t2, brw_imm_uw(2)); /* (Y & 0b1) << 2 */
956      brw_OR(&func, t1, t1, t2); /* (X & ~0b1011) >> 1 | (Y & 0b1) << 2 */
957      brw_AND(&func, t2, X, brw_imm_uw(1)); /* X & 0b1 */
958      brw_OR(&func, Xp, t1, t2);
959      brw_AND(&func, t1, Y, brw_imm_uw(0xfffe)); /* Y & ~0b1 */
960      brw_SHL(&func, t1, t1, brw_imm_uw(1)); /* (Y & ~0b1) << 1 */
961      brw_AND(&func, t2, X, brw_imm_uw(8)); /* X & 0b1000 */
962      brw_SHR(&func, t2, t2, brw_imm_uw(2)); /* (X & 0b1000) >> 2 */
963      brw_OR(&func, t1, t1, t2); /* (Y & ~0b1) << 1 | (X & 0b1000) >> 2 */
964      brw_AND(&func, t2, X, brw_imm_uw(2)); /* X & 0b10 */
965      brw_SHR(&func, t2, t2, brw_imm_uw(1)); /* (X & 0b10) >> 1 */
966      brw_OR(&func, Yp, t1, t2);
967      SWAP_XY_AND_XPYP();
968   } else {
969      /* Applying the same logic as above, but in reverse, we obtain the
970       * formulas:
971       *
972       * X' = (X & ~0b101) << 1 | (Y & 0b10) << 2 | (Y & 0b1) << 1 | X & 0b1
973       * Y' = (Y & ~0b11) >> 1 | (X & 0b100) >> 2
974       */
975      brw_AND(&func, t1, X, brw_imm_uw(0xfffa)); /* X & ~0b101 */
976      brw_SHL(&func, t1, t1, brw_imm_uw(1)); /* (X & ~0b101) << 1 */
977      brw_AND(&func, t2, Y, brw_imm_uw(2)); /* Y & 0b10 */
978      brw_SHL(&func, t2, t2, brw_imm_uw(2)); /* (Y & 0b10) << 2 */
979      brw_OR(&func, t1, t1, t2); /* (X & ~0b101) << 1 | (Y & 0b10) << 2 */
980      brw_AND(&func, t2, Y, brw_imm_uw(1)); /* Y & 0b1 */
981      brw_SHL(&func, t2, t2, brw_imm_uw(1)); /* (Y & 0b1) << 1 */
982      brw_OR(&func, t1, t1, t2); /* (X & ~0b101) << 1 | (Y & 0b10) << 2
983                                    | (Y & 0b1) << 1 */
984      brw_AND(&func, t2, X, brw_imm_uw(1)); /* X & 0b1 */
985      brw_OR(&func, Xp, t1, t2);
986      brw_AND(&func, t1, Y, brw_imm_uw(0xfffc)); /* Y & ~0b11 */
987      brw_SHR(&func, t1, t1, brw_imm_uw(1)); /* (Y & ~0b11) >> 1 */
988      brw_AND(&func, t2, X, brw_imm_uw(4)); /* X & 0b100 */
989      brw_SHR(&func, t2, t2, brw_imm_uw(2)); /* (X & 0b100) >> 2 */
990      brw_OR(&func, Yp, t1, t2);
991      SWAP_XY_AND_XPYP();
992   }
993}
994
995/**
996 * Emit code to compensate for the difference between MSAA and non-MSAA
997 * surfaces.
998 *
999 * This code modifies the X and Y coordinates according to the formula:
1000 *
1001 *   (X', Y', S') = encode_msaa(num_samples, IMS, X, Y, S)
1002 *
1003 * (See brw_blorp_blit_program).
1004 */
1005void
1006brw_blorp_blit_program::encode_msaa(unsigned num_samples,
1007                                    intel_msaa_layout layout)
1008{
1009   switch (layout) {
1010   case INTEL_MSAA_LAYOUT_NONE:
1011      /* No translation necessary, and S should already be zero. */
1012      assert(s_is_zero);
1013      break;
1014   case INTEL_MSAA_LAYOUT_CMS:
1015      /* We can't compensate for compressed layout since at this point in the
1016       * program we haven't read from the MCS buffer.
1017       */
1018      assert(!"Bad layout in encode_msaa");
1019      break;
1020   case INTEL_MSAA_LAYOUT_UMS:
1021      /* No translation necessary. */
1022      break;
1023   case INTEL_MSAA_LAYOUT_IMS:
1024      switch (num_samples) {
1025      case 4:
1026         /* encode_msaa(4, IMS, X, Y, S) = (X', Y', 0)
1027          *   where X' = (X & ~0b1) << 1 | (S & 0b1) << 1 | (X & 0b1)
1028          *         Y' = (Y & ~0b1) << 1 | (S & 0b10) | (Y & 0b1)
1029          */
1030         brw_AND(&func, t1, X, brw_imm_uw(0xfffe)); /* X & ~0b1 */
1031         if (!s_is_zero) {
1032            brw_AND(&func, t2, S, brw_imm_uw(1)); /* S & 0b1 */
1033            brw_OR(&func, t1, t1, t2); /* (X & ~0b1) | (S & 0b1) */
1034         }
1035         brw_SHL(&func, t1, t1, brw_imm_uw(1)); /* (X & ~0b1) << 1
1036                                                   | (S & 0b1) << 1 */
1037         brw_AND(&func, t2, X, brw_imm_uw(1)); /* X & 0b1 */
1038         brw_OR(&func, Xp, t1, t2);
1039         brw_AND(&func, t1, Y, brw_imm_uw(0xfffe)); /* Y & ~0b1 */
1040         brw_SHL(&func, t1, t1, brw_imm_uw(1)); /* (Y & ~0b1) << 1 */
1041         if (!s_is_zero) {
1042            brw_AND(&func, t2, S, brw_imm_uw(2)); /* S & 0b10 */
1043            brw_OR(&func, t1, t1, t2); /* (Y & ~0b1) << 1 | (S & 0b10) */
1044         }
1045         brw_AND(&func, t2, Y, brw_imm_uw(1)); /* Y & 0b1 */
1046         brw_OR(&func, Yp, t1, t2);
1047         break;
1048      case 8:
1049         /* encode_msaa(8, IMS, X, Y, S) = (X', Y', 0)
1050          *   where X' = (X & ~0b1) << 2 | (S & 0b100) | (S & 0b1) << 1
1051          *              | (X & 0b1)
1052          *         Y' = (Y & ~0b1) << 1 | (S & 0b10) | (Y & 0b1)
1053          */
1054         brw_AND(&func, t1, X, brw_imm_uw(0xfffe)); /* X & ~0b1 */
1055         brw_SHL(&func, t1, t1, brw_imm_uw(2)); /* (X & ~0b1) << 2 */
1056         if (!s_is_zero) {
1057            brw_AND(&func, t2, S, brw_imm_uw(4)); /* S & 0b100 */
1058            brw_OR(&func, t1, t1, t2); /* (X & ~0b1) << 2 | (S & 0b100) */
1059            brw_AND(&func, t2, S, brw_imm_uw(1)); /* S & 0b1 */
1060            brw_SHL(&func, t2, t2, brw_imm_uw(1)); /* (S & 0b1) << 1 */
1061            brw_OR(&func, t1, t1, t2); /* (X & ~0b1) << 2 | (S & 0b100)
1062                                          | (S & 0b1) << 1 */
1063         }
1064         brw_AND(&func, t2, X, brw_imm_uw(1)); /* X & 0b1 */
1065         brw_OR(&func, Xp, t1, t2);
1066         brw_AND(&func, t1, Y, brw_imm_uw(0xfffe)); /* Y & ~0b1 */
1067         brw_SHL(&func, t1, t1, brw_imm_uw(1)); /* (Y & ~0b1) << 1 */
1068         if (!s_is_zero) {
1069            brw_AND(&func, t2, S, brw_imm_uw(2)); /* S & 0b10 */
1070            brw_OR(&func, t1, t1, t2); /* (Y & ~0b1) << 1 | (S & 0b10) */
1071         }
1072         brw_AND(&func, t2, Y, brw_imm_uw(1)); /* Y & 0b1 */
1073         brw_OR(&func, Yp, t1, t2);
1074         break;
1075      }
1076      SWAP_XY_AND_XPYP();
1077      s_is_zero = true;
1078      break;
1079   }
1080}
1081
1082/**
1083 * Emit code to compensate for the difference between MSAA and non-MSAA
1084 * surfaces.
1085 *
1086 * This code modifies the X and Y coordinates according to the formula:
1087 *
1088 *   (X', Y', S) = decode_msaa(num_samples, IMS, X, Y, S)
1089 *
1090 * (See brw_blorp_blit_program).
1091 */
1092void
1093brw_blorp_blit_program::decode_msaa(unsigned num_samples,
1094                                    intel_msaa_layout layout)
1095{
1096   switch (layout) {
1097   case INTEL_MSAA_LAYOUT_NONE:
1098      /* No translation necessary, and S should already be zero. */
1099      assert(s_is_zero);
1100      break;
1101   case INTEL_MSAA_LAYOUT_CMS:
1102      /* We can't compensate for compressed layout since at this point in the
1103       * program we don't have access to the MCS buffer.
1104       */
1105      assert(!"Bad layout in encode_msaa");
1106      break;
1107   case INTEL_MSAA_LAYOUT_UMS:
1108      /* No translation necessary. */
1109      break;
1110   case INTEL_MSAA_LAYOUT_IMS:
1111      assert(s_is_zero);
1112      switch (num_samples) {
1113      case 4:
1114         /* decode_msaa(4, IMS, X, Y, 0) = (X', Y', S)
1115          *   where X' = (X & ~0b11) >> 1 | (X & 0b1)
1116          *         Y' = (Y & ~0b11) >> 1 | (Y & 0b1)
1117          *         S = (Y & 0b10) | (X & 0b10) >> 1
1118          */
1119         brw_AND(&func, t1, X, brw_imm_uw(0xfffc)); /* X & ~0b11 */
1120         brw_SHR(&func, t1, t1, brw_imm_uw(1)); /* (X & ~0b11) >> 1 */
1121         brw_AND(&func, t2, X, brw_imm_uw(1)); /* X & 0b1 */
1122         brw_OR(&func, Xp, t1, t2);
1123         brw_AND(&func, t1, Y, brw_imm_uw(0xfffc)); /* Y & ~0b11 */
1124         brw_SHR(&func, t1, t1, brw_imm_uw(1)); /* (Y & ~0b11) >> 1 */
1125         brw_AND(&func, t2, Y, brw_imm_uw(1)); /* Y & 0b1 */
1126         brw_OR(&func, Yp, t1, t2);
1127         brw_AND(&func, t1, Y, brw_imm_uw(2)); /* Y & 0b10 */
1128         brw_AND(&func, t2, X, brw_imm_uw(2)); /* X & 0b10 */
1129         brw_SHR(&func, t2, t2, brw_imm_uw(1)); /* (X & 0b10) >> 1 */
1130         brw_OR(&func, S, t1, t2);
1131         break;
1132      case 8:
1133         /* decode_msaa(8, IMS, X, Y, 0) = (X', Y', S)
1134          *   where X' = (X & ~0b111) >> 2 | (X & 0b1)
1135          *         Y' = (Y & ~0b11) >> 1 | (Y & 0b1)
1136          *         S = (X & 0b100) | (Y & 0b10) | (X & 0b10) >> 1
1137          */
1138         brw_AND(&func, t1, X, brw_imm_uw(0xfff8)); /* X & ~0b111 */
1139         brw_SHR(&func, t1, t1, brw_imm_uw(2)); /* (X & ~0b111) >> 2 */
1140         brw_AND(&func, t2, X, brw_imm_uw(1)); /* X & 0b1 */
1141         brw_OR(&func, Xp, t1, t2);
1142         brw_AND(&func, t1, Y, brw_imm_uw(0xfffc)); /* Y & ~0b11 */
1143         brw_SHR(&func, t1, t1, brw_imm_uw(1)); /* (Y & ~0b11) >> 1 */
1144         brw_AND(&func, t2, Y, brw_imm_uw(1)); /* Y & 0b1 */
1145         brw_OR(&func, Yp, t1, t2);
1146         brw_AND(&func, t1, X, brw_imm_uw(4)); /* X & 0b100 */
1147         brw_AND(&func, t2, Y, brw_imm_uw(2)); /* Y & 0b10 */
1148         brw_OR(&func, t1, t1, t2); /* (X & 0b100) | (Y & 0b10) */
1149         brw_AND(&func, t2, X, brw_imm_uw(2)); /* X & 0b10 */
1150         brw_SHR(&func, t2, t2, brw_imm_uw(1)); /* (X & 0b10) >> 1 */
1151         brw_OR(&func, S, t1, t2);
1152         break;
1153      }
1154      s_is_zero = false;
1155      SWAP_XY_AND_XPYP();
1156      break;
1157   }
1158}
1159
1160/**
1161 * Emit code that kills pixels whose X and Y coordinates are outside the
1162 * boundary of the rectangle defined by the push constants (dst_x0, dst_y0,
1163 * dst_x1, dst_y1).
1164 */
1165void
1166brw_blorp_blit_program::kill_if_outside_dst_rect()
1167{
1168   struct brw_reg f0 = brw_flag_reg();
1169   struct brw_reg g1 = retype(brw_vec1_grf(1, 7), BRW_REGISTER_TYPE_UW);
1170   struct brw_reg null16 = vec16(retype(brw_null_reg(), BRW_REGISTER_TYPE_UW));
1171
1172   brw_CMP(&func, null16, BRW_CONDITIONAL_GE, X, dst_x0);
1173   brw_CMP(&func, null16, BRW_CONDITIONAL_GE, Y, dst_y0);
1174   brw_CMP(&func, null16, BRW_CONDITIONAL_L, X, dst_x1);
1175   brw_CMP(&func, null16, BRW_CONDITIONAL_L, Y, dst_y1);
1176
1177   brw_set_predicate_control(&func, BRW_PREDICATE_NONE);
1178   brw_push_insn_state(&func);
1179   brw_set_mask_control(&func, BRW_MASK_DISABLE);
1180   brw_AND(&func, g1, f0, g1);
1181   brw_pop_insn_state(&func);
1182}
1183
1184/**
1185 * Emit code to translate from destination (X, Y) coordinates to source (X, Y)
1186 * coordinates.
1187 */
1188void
1189brw_blorp_blit_program::translate_dst_to_src()
1190{
1191   brw_MUL(&func, Xp, X, x_transform.multiplier);
1192   brw_MUL(&func, Yp, Y, y_transform.multiplier);
1193   brw_ADD(&func, Xp, Xp, x_transform.offset);
1194   brw_ADD(&func, Yp, Yp, y_transform.offset);
1195   SWAP_XY_AND_XPYP();
1196}
1197
1198/**
1199 * Emit code to transform the X and Y coordinates as needed for blending
1200 * together the different samples in an MSAA texture.
1201 */
1202void
1203brw_blorp_blit_program::single_to_blend()
1204{
1205   /* When looking up samples in an MSAA texture using the SAMPLE message,
1206    * Gen6 requires the texture coordinates to be odd integers (so that they
1207    * correspond to the center of a 2x2 block representing the four samples
1208    * that maxe up a pixel).  So we need to multiply our X and Y coordinates
1209    * each by 2 and then add 1.
1210    */
1211   brw_SHL(&func, t1, X, brw_imm_w(1));
1212   brw_SHL(&func, t2, Y, brw_imm_w(1));
1213   brw_ADD(&func, Xp, t1, brw_imm_w(1));
1214   brw_ADD(&func, Yp, t2, brw_imm_w(1));
1215   SWAP_XY_AND_XPYP();
1216}
1217
1218
1219/**
1220 * Count the number of trailing 1 bits in the given value.  For example:
1221 *
1222 * count_trailing_one_bits(0) == 0
1223 * count_trailing_one_bits(7) == 3
1224 * count_trailing_one_bits(11) == 2
1225 */
1226inline int count_trailing_one_bits(unsigned value)
1227{
1228#if defined(__GNUC__) && ((__GNUC__ * 100 + __GNUC_MINOR__) >= 304) /* gcc 3.4 or later */
1229   return __builtin_ctz(~value);
1230#else
1231   return _mesa_bitcount(value & ~(value + 1));
1232#endif
1233}
1234
1235
1236void
1237brw_blorp_blit_program::manual_blend(unsigned num_samples)
1238{
1239   if (key->tex_layout == INTEL_MSAA_LAYOUT_CMS)
1240      mcs_fetch();
1241
1242   /* We add together samples using a binary tree structure, e.g. for 4x MSAA:
1243    *
1244    *   result = ((sample[0] + sample[1]) + (sample[2] + sample[3])) / 4
1245    *
1246    * This ensures that when all samples have the same value, no numerical
1247    * precision is lost, since each addition operation always adds two equal
1248    * values, and summing two equal floating point values does not lose
1249    * precision.
1250    *
1251    * We perform this computation by treating the texture_data array as a
1252    * stack and performing the following operations:
1253    *
1254    * - push sample 0 onto stack
1255    * - push sample 1 onto stack
1256    * - add top two stack entries
1257    * - push sample 2 onto stack
1258    * - push sample 3 onto stack
1259    * - add top two stack entries
1260    * - add top two stack entries
1261    * - divide top stack entry by 4
1262    *
1263    * Note that after pushing sample i onto the stack, the number of add
1264    * operations we do is equal to the number of trailing 1 bits in i.  This
1265    * works provided the total number of samples is a power of two, which it
1266    * always is for i965.
1267    *
1268    * For integer formats, we replace the add operations with average
1269    * operations and skip the final division.
1270    */
1271   typedef struct brw_instruction *(*brw_op2_ptr)(struct brw_compile *,
1272                                                  struct brw_reg,
1273                                                  struct brw_reg,
1274                                                  struct brw_reg);
1275   brw_op2_ptr combine_op =
1276      key->texture_data_type == BRW_REGISTER_TYPE_F ? brw_ADD : brw_AVG;
1277   unsigned stack_depth = 0;
1278   for (unsigned i = 0; i < num_samples; ++i) {
1279      assert(stack_depth == _mesa_bitcount(i)); /* Loop invariant */
1280
1281      /* Push sample i onto the stack */
1282      assert(stack_depth < ARRAY_SIZE(texture_data));
1283      if (i == 0) {
1284         s_is_zero = true;
1285      } else {
1286         s_is_zero = false;
1287         brw_MOV(&func, S, brw_imm_uw(i));
1288      }
1289      texel_fetch(texture_data[stack_depth++]);
1290
1291      if (i == 0 && key->tex_layout == INTEL_MSAA_LAYOUT_CMS) {
1292         /* The Ivy Bridge PRM, Vol4 Part1 p27 (Multisample Control Surface)
1293          * suggests an optimization:
1294          *
1295          *     "A simple optimization with probable large return in
1296          *     performance is to compare the MCS value to zero (indicating
1297          *     all samples are on sample slice 0), and sample only from
1298          *     sample slice 0 using ld2dss if MCS is zero."
1299          *
1300          * Note that in the case where the MCS value is zero, sampling from
1301          * sample slice 0 using ld2dss and sampling from sample 0 using
1302          * ld2dms are equivalent (since all samples are on sample slice 0).
1303          * Since we have already sampled from sample 0, all we need to do is
1304          * skip the remaining fetches and averaging if MCS is zero.
1305          */
1306         brw_CMP(&func, vec16(brw_null_reg()), BRW_CONDITIONAL_NZ,
1307                 mcs_data, brw_imm_ud(0));
1308         brw_IF(&func, BRW_EXECUTE_16);
1309      }
1310
1311      /* Do count_trailing_one_bits(i) times */
1312      for (int j = count_trailing_one_bits(i); j-- > 0; ) {
1313         assert(stack_depth >= 2);
1314         --stack_depth;
1315
1316         /* TODO: should use a smaller loop bound for non_RGBA formats */
1317         for (int k = 0; k < 4; ++k) {
1318            combine_op(&func, offset(texture_data[stack_depth - 1], 2*k),
1319                       offset(vec8(texture_data[stack_depth - 1]), 2*k),
1320                       offset(vec8(texture_data[stack_depth]), 2*k));
1321         }
1322      }
1323   }
1324
1325   /* We should have just 1 sample on the stack now. */
1326   assert(stack_depth == 1);
1327
1328   if (key->texture_data_type == BRW_REGISTER_TYPE_F) {
1329      /* Scale the result down by a factor of num_samples */
1330      /* TODO: should use a smaller loop bound for non-RGBA formats */
1331      for (int j = 0; j < 4; ++j) {
1332         brw_MUL(&func, offset(texture_data[0], 2*j),
1333                 offset(vec8(texture_data[0]), 2*j),
1334                 brw_imm_f(1.0/num_samples));
1335      }
1336   }
1337
1338   if (key->tex_layout == INTEL_MSAA_LAYOUT_CMS)
1339      brw_ENDIF(&func);
1340}
1341
1342/**
1343 * Emit code to look up a value in the texture using the SAMPLE message (which
1344 * does blending of MSAA surfaces).
1345 */
1346void
1347brw_blorp_blit_program::sample(struct brw_reg dst)
1348{
1349   static const sampler_message_arg args[2] = {
1350      SAMPLER_MESSAGE_ARG_U_FLOAT,
1351      SAMPLER_MESSAGE_ARG_V_FLOAT
1352   };
1353
1354   texture_lookup(dst, GEN5_SAMPLER_MESSAGE_SAMPLE, args, ARRAY_SIZE(args));
1355}
1356
1357/**
1358 * Emit code to look up a value in the texture using the SAMPLE_LD message
1359 * (which does a simple texel fetch).
1360 */
1361void
1362brw_blorp_blit_program::texel_fetch(struct brw_reg dst)
1363{
1364   static const sampler_message_arg gen6_args[5] = {
1365      SAMPLER_MESSAGE_ARG_U_INT,
1366      SAMPLER_MESSAGE_ARG_V_INT,
1367      SAMPLER_MESSAGE_ARG_ZERO_INT, /* R */
1368      SAMPLER_MESSAGE_ARG_ZERO_INT, /* LOD */
1369      SAMPLER_MESSAGE_ARG_SI_INT
1370   };
1371   static const sampler_message_arg gen7_ld_args[3] = {
1372      SAMPLER_MESSAGE_ARG_U_INT,
1373      SAMPLER_MESSAGE_ARG_ZERO_INT, /* LOD */
1374      SAMPLER_MESSAGE_ARG_V_INT
1375   };
1376   static const sampler_message_arg gen7_ld2dss_args[3] = {
1377      SAMPLER_MESSAGE_ARG_SI_INT,
1378      SAMPLER_MESSAGE_ARG_U_INT,
1379      SAMPLER_MESSAGE_ARG_V_INT
1380   };
1381   static const sampler_message_arg gen7_ld2dms_args[4] = {
1382      SAMPLER_MESSAGE_ARG_SI_INT,
1383      SAMPLER_MESSAGE_ARG_MCS_INT,
1384      SAMPLER_MESSAGE_ARG_U_INT,
1385      SAMPLER_MESSAGE_ARG_V_INT
1386   };
1387
1388   switch (brw->intel.gen) {
1389   case 6:
1390      texture_lookup(dst, GEN5_SAMPLER_MESSAGE_SAMPLE_LD, gen6_args,
1391                     s_is_zero ? 2 : 5);
1392      break;
1393   case 7:
1394      switch (key->tex_layout) {
1395      case INTEL_MSAA_LAYOUT_IMS:
1396         /* From the Ivy Bridge PRM, Vol4 Part1 p72 (Multisampled Surface Storage
1397          * Format):
1398          *
1399          *     If this field is MSFMT_DEPTH_STENCIL
1400          *     [a.k.a. INTEL_MSAA_LAYOUT_IMS], the only sampling engine
1401          *     messages allowed are "ld2dms", "resinfo", and "sampleinfo".
1402          *
1403          * So fall through to emit the same message as we use for
1404          * INTEL_MSAA_LAYOUT_CMS.
1405          */
1406      case INTEL_MSAA_LAYOUT_CMS:
1407         texture_lookup(dst, GEN7_SAMPLER_MESSAGE_SAMPLE_LD2DMS,
1408                        gen7_ld2dms_args, ARRAY_SIZE(gen7_ld2dms_args));
1409         break;
1410      case INTEL_MSAA_LAYOUT_UMS:
1411         texture_lookup(dst, GEN7_SAMPLER_MESSAGE_SAMPLE_LD2DSS,
1412                        gen7_ld2dss_args, ARRAY_SIZE(gen7_ld2dss_args));
1413         break;
1414      case INTEL_MSAA_LAYOUT_NONE:
1415         assert(s_is_zero);
1416         texture_lookup(dst, GEN5_SAMPLER_MESSAGE_SAMPLE_LD, gen7_ld_args,
1417                        ARRAY_SIZE(gen7_ld_args));
1418         break;
1419      }
1420      break;
1421   default:
1422      assert(!"Should not get here.");
1423      break;
1424   };
1425}
1426
1427void
1428brw_blorp_blit_program::mcs_fetch()
1429{
1430   static const sampler_message_arg gen7_ld_mcs_args[2] = {
1431      SAMPLER_MESSAGE_ARG_U_INT,
1432      SAMPLER_MESSAGE_ARG_V_INT
1433   };
1434   texture_lookup(vec16(mcs_data), GEN7_SAMPLER_MESSAGE_SAMPLE_LD_MCS,
1435                  gen7_ld_mcs_args, ARRAY_SIZE(gen7_ld_mcs_args));
1436}
1437
1438void
1439brw_blorp_blit_program::expand_to_32_bits(struct brw_reg src,
1440                                          struct brw_reg dst)
1441{
1442   brw_MOV(&func, vec8(dst), vec8(src));
1443   brw_set_compression_control(&func, BRW_COMPRESSION_2NDHALF);
1444   brw_MOV(&func, offset(vec8(dst), 1), suboffset(vec8(src), 8));
1445   brw_set_compression_control(&func, BRW_COMPRESSION_NONE);
1446}
1447
1448void
1449brw_blorp_blit_program::texture_lookup(struct brw_reg dst,
1450                                       GLuint msg_type,
1451                                       const sampler_message_arg *args,
1452                                       int num_args)
1453{
1454   struct brw_reg mrf =
1455      retype(vec16(brw_message_reg(base_mrf)), BRW_REGISTER_TYPE_UD);
1456   for (int arg = 0; arg < num_args; ++arg) {
1457      switch (args[arg]) {
1458      case SAMPLER_MESSAGE_ARG_U_FLOAT:
1459         expand_to_32_bits(X, retype(mrf, BRW_REGISTER_TYPE_F));
1460         break;
1461      case SAMPLER_MESSAGE_ARG_V_FLOAT:
1462         expand_to_32_bits(Y, retype(mrf, BRW_REGISTER_TYPE_F));
1463         break;
1464      case SAMPLER_MESSAGE_ARG_U_INT:
1465         expand_to_32_bits(X, mrf);
1466         break;
1467      case SAMPLER_MESSAGE_ARG_V_INT:
1468         expand_to_32_bits(Y, mrf);
1469         break;
1470      case SAMPLER_MESSAGE_ARG_SI_INT:
1471         /* Note: on Gen7, this code may be reached with s_is_zero==true
1472          * because in Gen7's ld2dss message, the sample index is the first
1473          * argument.  When this happens, we need to move a 0 into the
1474          * appropriate message register.
1475          */
1476         if (s_is_zero)
1477            brw_MOV(&func, mrf, brw_imm_ud(0));
1478         else
1479            expand_to_32_bits(S, mrf);
1480         break;
1481      case SAMPLER_MESSAGE_ARG_MCS_INT:
1482         switch (key->tex_layout) {
1483         case INTEL_MSAA_LAYOUT_CMS:
1484            brw_MOV(&func, mrf, mcs_data);
1485            break;
1486         case INTEL_MSAA_LAYOUT_IMS:
1487            /* When sampling from an IMS surface, MCS data is not relevant,
1488             * and the hardware ignores it.  So don't bother populating it.
1489             */
1490            break;
1491         default:
1492            /* We shouldn't be trying to send MCS data with any other
1493             * layouts.
1494             */
1495            assert (!"Unsupported layout for MCS data");
1496            break;
1497         }
1498         break;
1499      case SAMPLER_MESSAGE_ARG_ZERO_INT:
1500         brw_MOV(&func, mrf, brw_imm_ud(0));
1501         break;
1502      }
1503      mrf.nr += 2;
1504   }
1505
1506   brw_SAMPLE(&func,
1507              retype(dst, BRW_REGISTER_TYPE_UW) /* dest */,
1508              base_mrf /* msg_reg_nr */,
1509              brw_message_reg(base_mrf) /* src0 */,
1510              BRW_BLORP_TEXTURE_BINDING_TABLE_INDEX,
1511              0 /* sampler */,
1512              WRITEMASK_XYZW,
1513              msg_type,
1514              8 /* response_length.  TODO: should be smaller for non-RGBA formats? */,
1515              mrf.nr - base_mrf /* msg_length */,
1516              0 /* header_present */,
1517              BRW_SAMPLER_SIMD_MODE_SIMD16,
1518              BRW_SAMPLER_RETURN_FORMAT_FLOAT32);
1519}
1520
1521#undef X
1522#undef Y
1523#undef U
1524#undef V
1525#undef S
1526#undef SWAP_XY_AND_XPYP
1527
1528void
1529brw_blorp_blit_program::render_target_write()
1530{
1531   struct brw_reg mrf_rt_write =
1532      retype(vec16(brw_message_reg(base_mrf)), key->texture_data_type);
1533   int mrf_offset = 0;
1534
1535   /* If we may have killed pixels, then we need to send R0 and R1 in a header
1536    * so that the render target knows which pixels we killed.
1537    */
1538   bool use_header = key->use_kill;
1539   if (use_header) {
1540      /* Copy R0/1 to MRF */
1541      brw_MOV(&func, retype(mrf_rt_write, BRW_REGISTER_TYPE_UD),
1542              retype(R0, BRW_REGISTER_TYPE_UD));
1543      mrf_offset += 2;
1544   }
1545
1546   /* Copy texture data to MRFs */
1547   for (int i = 0; i < 4; ++i) {
1548      /* E.g. mov(16) m2.0<1>:f r2.0<8;8,1>:f { Align1, H1 } */
1549      brw_MOV(&func, offset(mrf_rt_write, mrf_offset),
1550              offset(vec8(texture_data[0]), 2*i));
1551      mrf_offset += 2;
1552   }
1553
1554   /* Now write to the render target and terminate the thread */
1555   brw_fb_WRITE(&func,
1556                16 /* dispatch_width */,
1557                base_mrf /* msg_reg_nr */,
1558                mrf_rt_write /* src0 */,
1559                BRW_DATAPORT_RENDER_TARGET_WRITE_SIMD16_SINGLE_SOURCE,
1560                BRW_BLORP_RENDERBUFFER_BINDING_TABLE_INDEX,
1561                mrf_offset /* msg_length.  TODO: Should be smaller for non-RGBA formats. */,
1562                0 /* response_length */,
1563                true /* eot */,
1564                use_header);
1565}
1566
1567
1568void
1569brw_blorp_coord_transform_params::setup(GLuint src0, GLuint dst0, GLuint dst1,
1570                                        bool mirror)
1571{
1572   if (!mirror) {
1573      /* When not mirroring a coordinate (say, X), we need:
1574       *   x' - src_x0 = x - dst_x0
1575       * Therefore:
1576       *   x' = 1*x + (src_x0 - dst_x0)
1577       */
1578      multiplier = 1;
1579      offset = src0 - dst0;
1580   } else {
1581      /* When mirroring X we need:
1582       *   x' - src_x0 = dst_x1 - x - 1
1583       * Therefore:
1584       *   x' = -1*x + (src_x0 + dst_x1 - 1)
1585       */
1586      multiplier = -1;
1587      offset = src0 + dst1 - 1;
1588   }
1589}
1590
1591
1592/**
1593 * Determine which MSAA layout the GPU pipeline should be configured for,
1594 * based on the chip generation, the number of samples, and the true layout of
1595 * the image in memory.
1596 */
1597inline intel_msaa_layout
1598compute_msaa_layout_for_pipeline(struct brw_context *brw, unsigned num_samples,
1599                                 intel_msaa_layout true_layout)
1600{
1601   if (num_samples <= 1) {
1602      /* When configuring the GPU for non-MSAA, we can still accommodate IMS
1603       * format buffers, by transforming coordinates appropriately.
1604       */
1605      assert(true_layout == INTEL_MSAA_LAYOUT_NONE ||
1606             true_layout == INTEL_MSAA_LAYOUT_IMS);
1607      return INTEL_MSAA_LAYOUT_NONE;
1608   } else {
1609      assert(true_layout != INTEL_MSAA_LAYOUT_NONE);
1610   }
1611
1612   /* Prior to Gen7, all MSAA surfaces use IMS layout. */
1613   if (brw->intel.gen == 6) {
1614      assert(true_layout == INTEL_MSAA_LAYOUT_IMS);
1615   }
1616
1617   return true_layout;
1618}
1619
1620
1621brw_blorp_blit_params::brw_blorp_blit_params(struct brw_context *brw,
1622                                             struct intel_mipmap_tree *src_mt,
1623                                             struct intel_mipmap_tree *dst_mt,
1624                                             GLuint src_x0, GLuint src_y0,
1625                                             GLuint dst_x0, GLuint dst_y0,
1626                                             GLuint dst_x1, GLuint dst_y1,
1627                                             bool mirror_x, bool mirror_y)
1628{
1629   src.set(brw, src_mt, 0, 0);
1630   dst.set(brw, dst_mt, 0, 0);
1631
1632   use_wm_prog = true;
1633   memset(&wm_prog_key, 0, sizeof(wm_prog_key));
1634
1635   /* texture_data_type indicates the register type that should be used to
1636    * manipulate texture data.
1637    */
1638   switch (_mesa_get_format_datatype(src_mt->format)) {
1639   case GL_UNSIGNED_NORMALIZED:
1640   case GL_SIGNED_NORMALIZED:
1641   case GL_FLOAT:
1642      wm_prog_key.texture_data_type = BRW_REGISTER_TYPE_F;
1643      break;
1644   case GL_UNSIGNED_INT:
1645      if (src_mt->format == MESA_FORMAT_S8) {
1646         /* We process stencil as though it's an unsigned normalized color */
1647         wm_prog_key.texture_data_type = BRW_REGISTER_TYPE_F;
1648      } else {
1649         wm_prog_key.texture_data_type = BRW_REGISTER_TYPE_UD;
1650      }
1651      break;
1652   case GL_INT:
1653      wm_prog_key.texture_data_type = BRW_REGISTER_TYPE_D;
1654      break;
1655   default:
1656      assert(!"Unrecognized blorp format");
1657      break;
1658   }
1659
1660   if (brw->intel.gen > 6) {
1661      /* Gen7's rendering hardware only supports the IMS layout for depth and
1662       * stencil render targets.  Blorp always maps its destination surface as
1663       * a color render target (even if it's actually a depth or stencil
1664       * buffer).  So if the destination is IMS, we'll have to map it as a
1665       * single-sampled texture and interleave the samples ourselves.
1666       */
1667      if (dst_mt->msaa_layout == INTEL_MSAA_LAYOUT_IMS)
1668         dst.num_samples = 0;
1669   }
1670
1671   if (dst.map_stencil_as_y_tiled && dst.num_samples > 1) {
1672      /* If the destination surface is a W-tiled multisampled stencil buffer
1673       * that we're mapping as Y tiled, then we need to arrange for the WM
1674       * program to run once per sample rather than once per pixel, because
1675       * the memory layout of related samples doesn't match between W and Y
1676       * tiling.
1677       */
1678      wm_prog_key.persample_msaa_dispatch = true;
1679   }
1680
1681   if (src.num_samples > 0 && dst.num_samples > 1) {
1682      /* We are blitting from a multisample buffer to a multisample buffer, so
1683       * we must preserve samples within a pixel.  This means we have to
1684       * arrange for the WM program to run once per sample rather than once
1685       * per pixel.
1686       */
1687      wm_prog_key.persample_msaa_dispatch = true;
1688   }
1689
1690   /* The render path must be configured to use the same number of samples as
1691    * the destination buffer.
1692    */
1693   num_samples = dst.num_samples;
1694
1695   GLenum base_format = _mesa_get_format_base_format(src_mt->format);
1696   if (base_format != GL_DEPTH_COMPONENT && /* TODO: what about depth/stencil? */
1697       base_format != GL_STENCIL_INDEX &&
1698       src_mt->num_samples > 1 && dst_mt->num_samples <= 1) {
1699      /* We are downsampling a color buffer, so blend. */
1700      wm_prog_key.blend = true;
1701   }
1702
1703   /* src_samples and dst_samples are the true sample counts */
1704   wm_prog_key.src_samples = src_mt->num_samples;
1705   wm_prog_key.dst_samples = dst_mt->num_samples;
1706
1707   /* tex_samples and rt_samples are the sample counts that are set up in
1708    * SURFACE_STATE.
1709    */
1710   wm_prog_key.tex_samples = src.num_samples;
1711   wm_prog_key.rt_samples  = dst.num_samples;
1712
1713   /* tex_layout and rt_layout indicate the MSAA layout the GPU pipeline will
1714    * use to access the source and destination surfaces.
1715    */
1716   wm_prog_key.tex_layout =
1717      compute_msaa_layout_for_pipeline(brw, src.num_samples, src.msaa_layout);
1718   wm_prog_key.rt_layout =
1719      compute_msaa_layout_for_pipeline(brw, dst.num_samples, dst.msaa_layout);
1720
1721   /* src_layout and dst_layout indicate the true MSAA layout used by src and
1722    * dst.
1723    */
1724   wm_prog_key.src_layout = src_mt->msaa_layout;
1725   wm_prog_key.dst_layout = dst_mt->msaa_layout;
1726
1727   wm_prog_key.src_tiled_w = src.map_stencil_as_y_tiled;
1728   wm_prog_key.dst_tiled_w = dst.map_stencil_as_y_tiled;
1729   x0 = wm_push_consts.dst_x0 = dst_x0;
1730   y0 = wm_push_consts.dst_y0 = dst_y0;
1731   x1 = wm_push_consts.dst_x1 = dst_x1;
1732   y1 = wm_push_consts.dst_y1 = dst_y1;
1733   wm_push_consts.x_transform.setup(src_x0, dst_x0, dst_x1, mirror_x);
1734   wm_push_consts.y_transform.setup(src_y0, dst_y0, dst_y1, mirror_y);
1735
1736   if (dst.num_samples <= 1 && dst_mt->num_samples > 1) {
1737      /* We must expand the rectangle we send through the rendering pipeline,
1738       * to account for the fact that we are mapping the destination region as
1739       * single-sampled when it is in fact multisampled.  We must also align
1740       * it to a multiple of the multisampling pattern, because the
1741       * differences between multisampled and single-sampled surface formats
1742       * will mean that pixels are scrambled within the multisampling pattern.
1743       * TODO: what if this makes the coordinates too large?
1744       *
1745       * Note: this only works if the destination surface uses the IMS layout.
1746       * If it's UMS, then we have no choice but to set up the rendering
1747       * pipeline as multisampled.
1748       */
1749      assert(dst_mt->msaa_layout == INTEL_MSAA_LAYOUT_IMS);
1750      switch (dst_mt->num_samples) {
1751      case 4:
1752         x0 = ROUND_DOWN_TO(x0 * 2, 4);
1753         y0 = ROUND_DOWN_TO(y0 * 2, 4);
1754         x1 = ALIGN(x1 * 2, 4);
1755         y1 = ALIGN(y1 * 2, 4);
1756         break;
1757      case 8:
1758         x0 = ROUND_DOWN_TO(x0 * 4, 8);
1759         y0 = ROUND_DOWN_TO(y0 * 2, 4);
1760         x1 = ALIGN(x1 * 4, 8);
1761         y1 = ALIGN(y1 * 2, 4);
1762         break;
1763      default:
1764         assert(!"Unrecognized sample count in brw_blorp_blit_params ctor");
1765         break;
1766      }
1767      wm_prog_key.use_kill = true;
1768   }
1769
1770   if (dst.map_stencil_as_y_tiled) {
1771      /* We must modify the rectangle we send through the rendering pipeline,
1772       * to account for the fact that we are mapping it as Y-tiled when it is
1773       * in fact W-tiled.  Y tiles have dimensions 128x32 whereas W tiles have
1774       * dimensions 64x64.  We must also align it to a multiple of the tile
1775       * size, because the differences between W and Y tiling formats will
1776       * mean that pixels are scrambled within the tile.
1777       *
1778       * Note: if the destination surface configured to use IMS layout, then
1779       * the effective tile size we need to align it to is smaller, because
1780       * each pixel covers a 2x2 or a 4x2 block of samples.
1781       *
1782       * TODO: what if this makes the coordinates too large?
1783       */
1784      unsigned x_align = 64, y_align = 64;
1785      if (dst_mt->msaa_layout == INTEL_MSAA_LAYOUT_IMS) {
1786         x_align /= (dst_mt->num_samples == 4 ? 2 : 4);
1787         y_align /= 2;
1788      }
1789      x0 = ROUND_DOWN_TO(x0, x_align) * 2;
1790      y0 = ROUND_DOWN_TO(y0, y_align) / 2;
1791      x1 = ALIGN(x1, x_align) * 2;
1792      y1 = ALIGN(y1, y_align) / 2;
1793      wm_prog_key.use_kill = true;
1794   }
1795}
1796
1797uint32_t
1798brw_blorp_blit_params::get_wm_prog(struct brw_context *brw,
1799                                   brw_blorp_prog_data **prog_data) const
1800{
1801   uint32_t prog_offset;
1802   if (!brw_search_cache(&brw->cache, BRW_BLORP_BLIT_PROG,
1803                         &this->wm_prog_key, sizeof(this->wm_prog_key),
1804                         &prog_offset, prog_data)) {
1805      brw_blorp_blit_program prog(brw, &this->wm_prog_key);
1806      GLuint program_size;
1807      const GLuint *program = prog.compile(brw, &program_size);
1808      brw_upload_cache(&brw->cache, BRW_BLORP_BLIT_PROG,
1809                       &this->wm_prog_key, sizeof(this->wm_prog_key),
1810                       program, program_size,
1811                       &prog.prog_data, sizeof(prog.prog_data),
1812                       &prog_offset, prog_data);
1813   }
1814   return prog_offset;
1815}
1816