brw_wm.c revision 6cc14c2493bb6957f2581671020809e90a8d8643
1/*
2 Copyright (C) Intel Corp.  2006.  All Rights Reserved.
3 Intel funded Tungsten Graphics (http://www.tungstengraphics.com) to
4 develop this 3D driver.
5
6 Permission is hereby granted, free of charge, to any person obtaining
7 a copy of this software and associated documentation files (the
8 "Software"), to deal in the Software without restriction, including
9 without limitation the rights to use, copy, modify, merge, publish,
10 distribute, sublicense, and/or sell copies of the Software, and to
11 permit persons to whom the Software is furnished to do so, subject to
12 the following conditions:
13
14 The above copyright notice and this permission notice (including the
15 next paragraph) shall be included in all copies or substantial
16 portions of the Software.
17
18 THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
19 EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
20 MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
21 IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
22 LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
23 OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
24 WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
25
26 **********************************************************************/
27 /*
28  * Authors:
29  *   Keith Whitwell <keith@tungstengraphics.com>
30  */
31
32#include "brw_context.h"
33#include "brw_wm.h"
34#include "brw_state.h"
35#include "main/formats.h"
36#include "main/fbobject.h"
37#include "main/samplerobj.h"
38#include "program/prog_parameter.h"
39
40#include "glsl/ralloc.h"
41
42/** Return number of src args for given instruction */
43GLuint brw_wm_nr_args( GLuint opcode )
44{
45   switch (opcode) {
46   case WM_FRONTFACING:
47   case WM_PIXELXY:
48      return 0;
49   case WM_CINTERP:
50   case WM_WPOSXY:
51   case WM_DELTAXY:
52      return 1;
53   case WM_LINTERP:
54   case WM_PIXELW:
55      return 2;
56   case WM_FB_WRITE:
57   case WM_PINTERP:
58      return 3;
59   default:
60      assert(opcode < MAX_OPCODE);
61      return _mesa_num_inst_src_regs(opcode);
62   }
63}
64
65
66GLuint brw_wm_is_scalar_result( GLuint opcode )
67{
68   switch (opcode) {
69   case OPCODE_COS:
70   case OPCODE_EX2:
71   case OPCODE_LG2:
72   case OPCODE_POW:
73   case OPCODE_RCP:
74   case OPCODE_RSQ:
75   case OPCODE_SIN:
76   case OPCODE_DP2:
77   case OPCODE_DP3:
78   case OPCODE_DP4:
79   case OPCODE_DPH:
80   case OPCODE_DST:
81      return 1;
82
83   default:
84      return 0;
85   }
86}
87
88
89/**
90 * Do GPU code generation for non-GLSL shader.  non-GLSL shaders have
91 * no flow control instructions so we can more readily do SSA-style
92 * optimizations.
93 */
94static void
95brw_wm_non_glsl_emit(struct brw_context *brw, struct brw_wm_compile *c)
96{
97   /* Augment fragment program.  Add instructions for pre- and
98    * post-fragment-program tasks such as interpolation and fogging.
99    */
100   brw_wm_pass_fp(c);
101
102   /* Translate to intermediate representation.  Build register usage
103    * chains.
104    */
105   brw_wm_pass0(c);
106
107   /* Dead code removal.
108    */
109   brw_wm_pass1(c);
110
111   /* Register allocation.
112    * Divide by two because we operate on 16 pixels at a time and require
113    * two GRF entries for each logical shader register.
114    */
115   c->grf_limit = BRW_WM_MAX_GRF / 2;
116
117   brw_wm_pass2(c);
118
119   /* how many general-purpose registers are used */
120   c->prog_data.reg_blocks = brw_register_blocks(c->max_wm_grf);
121
122   /* Emit GEN4 code.
123    */
124   brw_wm_emit(c);
125}
126
127
128/**
129 * Return a bitfield where bit n is set if barycentric interpolation mode n
130 * (see enum brw_wm_barycentric_interp_mode) is needed by the fragment shader.
131 */
132static unsigned
133brw_compute_barycentric_interp_modes(struct brw_context *brw,
134                                     bool shade_model_flat,
135                                     const struct gl_fragment_program *fprog)
136{
137   unsigned barycentric_interp_modes = 0;
138   int attr;
139
140   /* Loop through all fragment shader inputs to figure out what interpolation
141    * modes are in use, and set the appropriate bits in
142    * barycentric_interp_modes.
143    */
144   for (attr = 0; attr < FRAG_ATTRIB_MAX; ++attr) {
145      enum glsl_interp_qualifier interp_qualifier =
146         fprog->InterpQualifier[attr];
147      bool is_centroid = fprog->IsCentroid & BITFIELD64_BIT(attr);
148      bool is_gl_Color = attr == FRAG_ATTRIB_COL0 || attr == FRAG_ATTRIB_COL1;
149
150      /* Ignore unused inputs. */
151      if (!(fprog->Base.InputsRead & BITFIELD64_BIT(attr)))
152         continue;
153
154      /* Ignore WPOS and FACE, because they don't require interpolation. */
155      if (attr == FRAG_ATTRIB_WPOS || attr == FRAG_ATTRIB_FACE)
156         continue;
157
158      /* Determine the set (or sets) of barycentric coordinates needed to
159       * interpolate this variable.  Note that when
160       * brw->needs_unlit_centroid_workaround is set, centroid interpolation
161       * uses PIXEL interpolation for unlit pixels and CENTROID interpolation
162       * for lit pixels, so we need both sets of barycentric coordinates.
163       */
164      if (interp_qualifier == INTERP_QUALIFIER_NOPERSPECTIVE) {
165         if (is_centroid) {
166            barycentric_interp_modes |=
167               1 << BRW_WM_NONPERSPECTIVE_CENTROID_BARYCENTRIC;
168         }
169         if (!is_centroid || brw->needs_unlit_centroid_workaround) {
170            barycentric_interp_modes |=
171               1 << BRW_WM_NONPERSPECTIVE_PIXEL_BARYCENTRIC;
172         }
173      } else if (interp_qualifier == INTERP_QUALIFIER_SMOOTH ||
174                 (!(shade_model_flat && is_gl_Color) &&
175                  interp_qualifier == INTERP_QUALIFIER_NONE)) {
176         if (is_centroid) {
177            barycentric_interp_modes |=
178               1 << BRW_WM_PERSPECTIVE_CENTROID_BARYCENTRIC;
179         }
180         if (!is_centroid || brw->needs_unlit_centroid_workaround) {
181            barycentric_interp_modes |=
182               1 << BRW_WM_PERSPECTIVE_PIXEL_BARYCENTRIC;
183         }
184      }
185   }
186
187   return barycentric_interp_modes;
188}
189
190
191void
192brw_wm_payload_setup(struct brw_context *brw,
193		     struct brw_wm_compile *c)
194{
195   struct intel_context *intel = &brw->intel;
196   bool uses_depth = (c->fp->program.Base.InputsRead &
197		      (1 << FRAG_ATTRIB_WPOS)) != 0;
198   unsigned barycentric_interp_modes = c->prog_data.barycentric_interp_modes;
199   int i;
200
201   if (intel->gen >= 6) {
202      /* R0-1: masks, pixel X/Y coordinates. */
203      c->nr_payload_regs = 2;
204      /* R2: only for 32-pixel dispatch.*/
205
206      /* R3-26: barycentric interpolation coordinates.  These appear in the
207       * same order that they appear in the brw_wm_barycentric_interp_mode
208       * enum.  Each set of coordinates occupies 2 registers if dispatch width
209       * == 8 and 4 registers if dispatch width == 16.  Coordinates only
210       * appear if they were enabled using the "Barycentric Interpolation
211       * Mode" bits in WM_STATE.
212       */
213      for (i = 0; i < BRW_WM_BARYCENTRIC_INTERP_MODE_COUNT; ++i) {
214         if (barycentric_interp_modes & (1 << i)) {
215            c->barycentric_coord_reg[i] = c->nr_payload_regs;
216            c->nr_payload_regs += 2;
217            if (c->dispatch_width == 16) {
218               c->nr_payload_regs += 2;
219            }
220         }
221      }
222
223      /* R27: interpolated depth if uses source depth */
224      if (uses_depth) {
225	 c->source_depth_reg = c->nr_payload_regs;
226	 c->nr_payload_regs++;
227	 if (c->dispatch_width == 16) {
228	    /* R28: interpolated depth if not 8-wide. */
229	    c->nr_payload_regs++;
230	 }
231      }
232      /* R29: interpolated W set if GEN6_WM_USES_SOURCE_W.
233       */
234      if (uses_depth) {
235	 c->source_w_reg = c->nr_payload_regs;
236	 c->nr_payload_regs++;
237	 if (c->dispatch_width == 16) {
238	    /* R30: interpolated W if not 8-wide. */
239	    c->nr_payload_regs++;
240	 }
241      }
242      /* R31: MSAA position offsets. */
243      /* R32-: bary for 32-pixel. */
244      /* R58-59: interp W for 32-pixel. */
245
246      if (c->fp->program.Base.OutputsWritten &
247	  BITFIELD64_BIT(FRAG_RESULT_DEPTH)) {
248	 c->source_depth_to_render_target = true;
249	 c->computes_depth = true;
250      }
251   } else {
252      brw_wm_lookup_iz(intel, c);
253   }
254}
255
256/**
257 * All Mesa program -> GPU code generation goes through this function.
258 * Depending on the instructions used (i.e. flow control instructions)
259 * we'll use one of two code generators.
260 */
261bool do_wm_prog(struct brw_context *brw,
262		struct gl_shader_program *prog,
263		struct brw_fragment_program *fp,
264		struct brw_wm_prog_key *key)
265{
266   struct intel_context *intel = &brw->intel;
267   struct brw_wm_compile *c;
268   const GLuint *program;
269   GLuint program_size;
270
271   c = brw->wm.compile_data;
272   if (c == NULL) {
273      brw->wm.compile_data = rzalloc(NULL, struct brw_wm_compile);
274      c = brw->wm.compile_data;
275      if (c == NULL) {
276         /* Ouch - big out of memory problem.  Can't continue
277          * without triggering a segfault, no way to signal,
278          * so just return.
279          */
280         return false;
281      }
282   } else {
283      void *instruction = c->instruction;
284      void *prog_instructions = c->prog_instructions;
285      void *vreg = c->vreg;
286      void *refs = c->refs;
287      memset(c, 0, sizeof(*brw->wm.compile_data));
288      c->instruction = instruction;
289      c->prog_instructions = prog_instructions;
290      c->vreg = vreg;
291      c->refs = refs;
292   }
293   memcpy(&c->key, key, sizeof(*key));
294
295   c->fp = fp;
296   c->env_param = brw->intel.ctx.FragmentProgram.Parameters;
297
298   brw_init_compile(brw, &c->func, c);
299
300   c->prog_data.barycentric_interp_modes =
301      brw_compute_barycentric_interp_modes(brw, c->key.flat_shade,
302                                           &fp->program);
303
304   if (prog && prog->_LinkedShaders[MESA_SHADER_FRAGMENT]) {
305      if (!brw_wm_fs_emit(brw, c, prog))
306	 return false;
307   } else {
308      if (!c->instruction) {
309	 c->instruction = rzalloc_array(c, struct brw_wm_instruction, BRW_WM_MAX_INSN);
310	 c->prog_instructions = rzalloc_array(c, struct prog_instruction, BRW_WM_MAX_INSN);
311	 c->vreg = rzalloc_array(c, struct brw_wm_value, BRW_WM_MAX_VREG);
312	 c->refs = rzalloc_array(c, struct brw_wm_ref, BRW_WM_MAX_REF);
313      }
314
315      /* Fallback for fixed function and ARB_fp shaders. */
316      c->dispatch_width = 16;
317      brw_wm_payload_setup(brw, c);
318      brw_wm_non_glsl_emit(brw, c);
319      c->prog_data.dispatch_width = 16;
320   }
321
322   /* Scratch space is used for register spilling */
323   if (c->last_scratch) {
324      perf_debug("Fragment shader triggered register spilling.  "
325                 "Try reducing the number of live scalar values to "
326                 "improve performance.\n");
327
328      c->prog_data.total_scratch = brw_get_scratch_size(c->last_scratch);
329
330      brw_get_scratch_bo(intel, &brw->wm.scratch_bo,
331			 c->prog_data.total_scratch * brw->max_wm_threads);
332   }
333
334   if (unlikely(INTEL_DEBUG & DEBUG_WM))
335      fprintf(stderr, "\n");
336
337   /* get the program
338    */
339   program = brw_get_program(&c->func, &program_size);
340
341   brw_upload_cache(&brw->cache, BRW_WM_PROG,
342		    &c->key, sizeof(c->key),
343		    program, program_size,
344		    &c->prog_data, sizeof(c->prog_data),
345		    &brw->wm.prog_offset, &brw->wm.prog_data);
346
347   return true;
348}
349
350static bool
351key_debug(const char *name, int a, int b)
352{
353   if (a != b) {
354      perf_debug("  %s %d->%d\n", name, a, b);
355      return true;
356   } else {
357      return false;
358   }
359}
360
361bool
362brw_debug_recompile_sampler_key(const struct brw_sampler_prog_key_data *old_key,
363                                const struct brw_sampler_prog_key_data *key)
364{
365   bool found = false;
366
367   for (unsigned int i = 0; i < BRW_MAX_TEX_UNIT; i++) {
368      found |= key_debug("EXT_texture_swizzle or DEPTH_TEXTURE_MODE",
369                         old_key->swizzles[i], key->swizzles[i]);
370   }
371   found |= key_debug("GL_CLAMP enabled on any texture unit's 1st coordinate",
372                      old_key->gl_clamp_mask[0], key->gl_clamp_mask[0]);
373   found |= key_debug("GL_CLAMP enabled on any texture unit's 2nd coordinate",
374                      old_key->gl_clamp_mask[1], key->gl_clamp_mask[1]);
375   found |= key_debug("GL_CLAMP enabled on any texture unit's 3rd coordinate",
376                      old_key->gl_clamp_mask[2], key->gl_clamp_mask[2]);
377   found |= key_debug("GL_MESA_ycbcr texturing\n",
378                      old_key->yuvtex_mask, key->yuvtex_mask);
379   found |= key_debug("GL_MESA_ycbcr UV swapping\n",
380                      old_key->yuvtex_swap_mask, key->yuvtex_swap_mask);
381
382   return found;
383}
384
385void
386brw_wm_debug_recompile(struct brw_context *brw,
387                       struct gl_shader_program *prog,
388                       const struct brw_wm_prog_key *key)
389{
390   struct brw_cache_item *c = NULL;
391   const struct brw_wm_prog_key *old_key = NULL;
392   bool found = false;
393
394   perf_debug("Recompiling fragment shader for program %d\n", prog->Name);
395
396   for (unsigned int i = 0; i < brw->cache.size; i++) {
397      for (c = brw->cache.items[i]; c; c = c->next) {
398         if (c->cache_id == BRW_WM_PROG) {
399            old_key = c->key;
400
401            if (old_key->program_string_id == key->program_string_id)
402               break;
403         }
404      }
405      if (c)
406         break;
407   }
408
409   if (!c) {
410      perf_debug("  Didn't find previous compile in the shader cache for "
411                 "debug\n");
412      return;
413   }
414
415   found |= key_debug("alphatest, computed depth, depth test, or depth write",
416                      old_key->iz_lookup, key->iz_lookup);
417   found |= key_debug("depth statistics", old_key->stats_wm, key->stats_wm);
418   found |= key_debug("flat shading", old_key->flat_shade, key->flat_shade);
419   found |= key_debug("number of color buffers", old_key->nr_color_regions, key->nr_color_regions);
420   found |= key_debug("rendering to FBO", old_key->render_to_fbo, key->render_to_fbo);
421   found |= key_debug("fragment color clamping", old_key->clamp_fragment_color, key->clamp_fragment_color);
422   found |= key_debug("line smoothing", old_key->line_aa, key->line_aa);
423   found |= key_debug("proj_attrib_mask", old_key->proj_attrib_mask, key->proj_attrib_mask);
424   found |= key_debug("renderbuffer height", old_key->drawable_height, key->drawable_height);
425   found |= key_debug("vertex shader outputs", old_key->vp_outputs_written, key->vp_outputs_written);
426
427   found |= brw_debug_recompile_sampler_key(&old_key->tex, &key->tex);
428
429   if (!found) {
430      perf_debug("  Something else\n");
431   }
432}
433
434void
435brw_populate_sampler_prog_key_data(struct gl_context *ctx,
436				   const struct gl_program *prog,
437				   struct brw_sampler_prog_key_data *key)
438{
439   for (int i = 0; i < BRW_MAX_TEX_UNIT; i++) {
440      key->swizzles[i] = SWIZZLE_NOOP;
441
442      if (!prog->TexturesUsed[i])
443	 continue;
444
445      const struct gl_texture_unit *unit = &ctx->Texture.Unit[i];
446
447      if (unit->_ReallyEnabled && unit->_Current->Target != GL_TEXTURE_BUFFER) {
448	 const struct gl_texture_object *t = unit->_Current;
449	 const struct gl_texture_image *img = t->Image[0][t->BaseLevel];
450	 struct gl_sampler_object *sampler = _mesa_get_samplerobj(ctx, i);
451	 int swizzles[SWIZZLE_NIL + 1] = {
452	    SWIZZLE_X,
453	    SWIZZLE_Y,
454	    SWIZZLE_Z,
455	    SWIZZLE_W,
456	    SWIZZLE_ZERO,
457	    SWIZZLE_ONE,
458	    SWIZZLE_NIL
459	 };
460
461	 if (img->_BaseFormat == GL_DEPTH_COMPONENT ||
462	     img->_BaseFormat == GL_DEPTH_STENCIL) {
463	    /* We handle GL_DEPTH_TEXTURE_MODE here instead of as surface
464	     * format overrides because shadow comparison always returns the
465	     * result of the comparison in all channels anyway.
466	     */
467	    switch (t->DepthMode) {
468	    case GL_ALPHA:
469	       swizzles[0] = SWIZZLE_ZERO;
470	       swizzles[1] = SWIZZLE_ZERO;
471	       swizzles[2] = SWIZZLE_ZERO;
472	       swizzles[3] = SWIZZLE_X;
473	       break;
474	    case GL_LUMINANCE:
475	       swizzles[0] = SWIZZLE_X;
476	       swizzles[1] = SWIZZLE_X;
477	       swizzles[2] = SWIZZLE_X;
478	       swizzles[3] = SWIZZLE_ONE;
479	       break;
480	    case GL_INTENSITY:
481	       swizzles[0] = SWIZZLE_X;
482	       swizzles[1] = SWIZZLE_X;
483	       swizzles[2] = SWIZZLE_X;
484	       swizzles[3] = SWIZZLE_X;
485	       break;
486	    case GL_RED:
487	       swizzles[0] = SWIZZLE_X;
488	       swizzles[1] = SWIZZLE_ZERO;
489	       swizzles[2] = SWIZZLE_ZERO;
490	       swizzles[3] = SWIZZLE_ONE;
491	       break;
492	    }
493	 }
494
495	 if (img->InternalFormat == GL_YCBCR_MESA) {
496	    key->yuvtex_mask |= 1 << i;
497	    if (img->TexFormat == MESA_FORMAT_YCBCR)
498		key->yuvtex_swap_mask |= 1 << i;
499	 }
500
501	 key->swizzles[i] =
502	    MAKE_SWIZZLE4(swizzles[GET_SWZ(t->_Swizzle, 0)],
503			  swizzles[GET_SWZ(t->_Swizzle, 1)],
504			  swizzles[GET_SWZ(t->_Swizzle, 2)],
505			  swizzles[GET_SWZ(t->_Swizzle, 3)]);
506
507	 if (sampler->MinFilter != GL_NEAREST &&
508	     sampler->MagFilter != GL_NEAREST) {
509	    if (sampler->WrapS == GL_CLAMP)
510	       key->gl_clamp_mask[0] |= 1 << i;
511	    if (sampler->WrapT == GL_CLAMP)
512	       key->gl_clamp_mask[1] |= 1 << i;
513	    if (sampler->WrapR == GL_CLAMP)
514	       key->gl_clamp_mask[2] |= 1 << i;
515	 }
516      }
517   }
518}
519
520static void brw_wm_populate_key( struct brw_context *brw,
521				 struct brw_wm_prog_key *key )
522{
523   struct gl_context *ctx = &brw->intel.ctx;
524   struct intel_context *intel = &brw->intel;
525   /* BRW_NEW_FRAGMENT_PROGRAM */
526   const struct brw_fragment_program *fp =
527      (struct brw_fragment_program *)brw->fragment_program;
528   const struct gl_program *prog = (struct gl_program *) brw->fragment_program;
529   GLuint lookup = 0;
530   GLuint line_aa;
531   bool program_uses_dfdy = fp->program.UsesDFdy;
532
533   memset(key, 0, sizeof(*key));
534
535   /* Build the index for table lookup
536    */
537   if (intel->gen < 6) {
538      /* _NEW_COLOR */
539      if (fp->program.UsesKill || ctx->Color.AlphaEnabled)
540	 lookup |= IZ_PS_KILL_ALPHATEST_BIT;
541
542      if (fp->program.Base.OutputsWritten & BITFIELD64_BIT(FRAG_RESULT_DEPTH))
543	 lookup |= IZ_PS_COMPUTES_DEPTH_BIT;
544
545      /* _NEW_DEPTH */
546      if (ctx->Depth.Test)
547	 lookup |= IZ_DEPTH_TEST_ENABLE_BIT;
548
549      if (ctx->Depth.Test && ctx->Depth.Mask) /* ?? */
550	 lookup |= IZ_DEPTH_WRITE_ENABLE_BIT;
551
552      /* _NEW_STENCIL */
553      if (ctx->Stencil._Enabled) {
554	 lookup |= IZ_STENCIL_TEST_ENABLE_BIT;
555
556	 if (ctx->Stencil.WriteMask[0] ||
557	     ctx->Stencil.WriteMask[ctx->Stencil._BackFace])
558	    lookup |= IZ_STENCIL_WRITE_ENABLE_BIT;
559      }
560      key->iz_lookup = lookup;
561   }
562
563   line_aa = AA_NEVER;
564
565   /* _NEW_LINE, _NEW_POLYGON, BRW_NEW_REDUCED_PRIMITIVE */
566   if (ctx->Line.SmoothFlag) {
567      if (brw->intel.reduced_primitive == GL_LINES) {
568	 line_aa = AA_ALWAYS;
569      }
570      else if (brw->intel.reduced_primitive == GL_TRIANGLES) {
571	 if (ctx->Polygon.FrontMode == GL_LINE) {
572	    line_aa = AA_SOMETIMES;
573
574	    if (ctx->Polygon.BackMode == GL_LINE ||
575		(ctx->Polygon.CullFlag &&
576		 ctx->Polygon.CullFaceMode == GL_BACK))
577	       line_aa = AA_ALWAYS;
578	 }
579	 else if (ctx->Polygon.BackMode == GL_LINE) {
580	    line_aa = AA_SOMETIMES;
581
582	    if ((ctx->Polygon.CullFlag &&
583		 ctx->Polygon.CullFaceMode == GL_FRONT))
584	       line_aa = AA_ALWAYS;
585	 }
586      }
587   }
588
589   key->line_aa = line_aa;
590
591   if (intel->gen < 6)
592      key->stats_wm = brw->intel.stats_wm;
593
594   /* BRW_NEW_WM_INPUT_DIMENSIONS */
595   key->proj_attrib_mask = brw->wm.input_size_masks[4-1];
596
597   /* _NEW_LIGHT */
598   key->flat_shade = (ctx->Light.ShadeModel == GL_FLAT);
599
600   /* _NEW_FRAG_CLAMP | _NEW_BUFFERS */
601   key->clamp_fragment_color = ctx->Color._ClampFragmentColor;
602
603   /* _NEW_TEXTURE */
604   brw_populate_sampler_prog_key_data(ctx, prog, &key->tex);
605
606   /* _NEW_BUFFERS */
607   /*
608    * Include the draw buffer origin and height so that we can calculate
609    * fragment position values relative to the bottom left of the drawable,
610    * from the incoming screen origin relative position we get as part of our
611    * payload.
612    *
613    * This is only needed for the WM_WPOSXY opcode when the fragment program
614    * uses the gl_FragCoord input.
615    *
616    * We could avoid recompiling by including this as a constant referenced by
617    * our program, but if we were to do that it would also be nice to handle
618    * getting that constant updated at batchbuffer submit time (when we
619    * hold the lock and know where the buffer really is) rather than at emit
620    * time when we don't hold the lock and are just guessing.  We could also
621    * just avoid using this as key data if the program doesn't use
622    * fragment.position.
623    *
624    * For DRI2 the origin_x/y will always be (0,0) but we still need the
625    * drawable height in order to invert the Y axis.
626    */
627   if (fp->program.Base.InputsRead & FRAG_BIT_WPOS) {
628      key->drawable_height = ctx->DrawBuffer->Height;
629   }
630
631   if ((fp->program.Base.InputsRead & FRAG_BIT_WPOS) || program_uses_dfdy) {
632      key->render_to_fbo = _mesa_is_user_fbo(ctx->DrawBuffer);
633   }
634
635   /* _NEW_BUFFERS */
636   key->nr_color_regions = ctx->DrawBuffer->_NumColorDrawBuffers;
637  /* _NEW_MULTISAMPLE */
638   key->sample_alpha_to_coverage = ctx->Multisample.SampleAlphaToCoverage;
639
640   /* CACHE_NEW_VS_PROG */
641   if (intel->gen < 6)
642      key->vp_outputs_written = brw->vs.prog_data->outputs_written;
643
644   /* The unique fragment program ID */
645   key->program_string_id = fp->id;
646}
647
648
649static void
650brw_upload_wm_prog(struct brw_context *brw)
651{
652   struct intel_context *intel = &brw->intel;
653   struct gl_context *ctx = &intel->ctx;
654   struct brw_wm_prog_key key;
655   struct brw_fragment_program *fp = (struct brw_fragment_program *)
656      brw->fragment_program;
657
658   brw_wm_populate_key(brw, &key);
659
660   if (!brw_search_cache(&brw->cache, BRW_WM_PROG,
661			 &key, sizeof(key),
662			 &brw->wm.prog_offset, &brw->wm.prog_data)) {
663      bool success = do_wm_prog(brw, ctx->Shader._CurrentFragmentProgram, fp,
664				&key);
665      (void) success;
666      assert(success);
667   }
668}
669
670
671const struct brw_tracked_state brw_wm_prog = {
672   .dirty = {
673      .mesa  = (_NEW_COLOR |
674		_NEW_DEPTH |
675		_NEW_STENCIL |
676		_NEW_POLYGON |
677		_NEW_LINE |
678		_NEW_LIGHT |
679		_NEW_FRAG_CLAMP |
680		_NEW_BUFFERS |
681		_NEW_TEXTURE),
682      .brw   = (BRW_NEW_FRAGMENT_PROGRAM |
683		BRW_NEW_WM_INPUT_DIMENSIONS |
684		BRW_NEW_REDUCED_PRIMITIVE),
685      .cache = CACHE_NEW_VS_PROG,
686   },
687   .emit = brw_upload_wm_prog
688};
689
690