src/gallium/drivers/llvmpipe/lp_state_fs.c

   1 /**************************************************************************
   2  *
   3  * Copyright 2009 VMware, Inc.
   4  * Copyright 2007 Tungsten Graphics, Inc., Cedar Park, Texas.
   5  * All Rights Reserved.
   6  *
   7  * Permission is hereby granted, free of charge, to any person obtaining a
   8  * copy of this software and associated documentation files (the
   9  * "Software"), to deal in the Software without restriction, including
  10  * without limitation the rights to use, copy, modify, merge, publish,
  11  * distribute, sub license, and/or sell copies of the Software, and to
  12  * permit persons to whom the Software is furnished to do so, subject to
  13  * the following conditions:
  14  *
  15  * The above copyright notice and this permission notice (including the
  16  * next paragraph) shall be included in all copies or substantial portions
  17  * of the Software.
  18  *
  19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS
  20  * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  21  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT.
  22  * IN NO EVENT SHALL TUNGSTEN GRAPHICS AND/OR ITS SUPPLIERS BE LIABLE FOR
  23  * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
  24  * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
  25  * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  26  *
  27  **************************************************************************/
  28
  29 /**
  30  * @file
  31  * Code generate the whole fragment pipeline.
  32  *
  33  * The fragment pipeline consists of the following stages:
  34  * - triangle edge in/out testing
  35  * - scissor test
  36  * - stipple (TBI)
  37  * - early depth test
  38  * - fragment shader
  39  * - alpha test
  40  * - depth/stencil test
  41  * - blending
  42  *
  43  * This file has only the glue to assemble the fragment pipeline.  The actual
  44  * plumbing of converting Gallium state into LLVM IR is done elsewhere, in the
  45  * lp_bld_*.[ch] files, and in a complete generic and reusable way. Here we
  46  * muster the LLVM JIT execution engine to create a function that follows an
  47  * established binary interface and that can be called from C directly.
  48  *
  49  * A big source of complexity here is that we often want to run different
  50  * stages with different precisions and data types and precisions. For example,
  51  * the fragment shader needs typically to be done in floats, but the
  52  * depth/stencil test and blending is better done in the type that most closely
  53  * matches the depth/stencil and color buffer respectively.
  54  *
  55  * Since the width of a SIMD vector register stays the same regardless of the
  56  * element type, different types imply different number of elements, so we must
  57  * code generate more instances of the stages with larger types to be able to
  58  * feed/consume the stages with smaller types.
  59  *
  60  * @author Jose Fonseca <jfonseca@vmware.com>
  61  */
  62
  63 #include <limits.h>
  64 #include "pipe/p_defines.h"
  65 #include "util/u_inlines.h"
  66 #include "util/u_memory.h"
  67 #include "util/u_pointer.h"
  68 #include "util/u_format.h"
  69 #include "util/u_dump.h"
  70 #include "util/u_string.h"
  71 #include "os/os_time.h"
  72 #include "pipe/p_shader_tokens.h"
  73 #include "draw/draw_context.h"
  74 #include "tgsi/tgsi_dump.h"
  75 #include "tgsi/tgsi_scan.h"
  76 #include "tgsi/tgsi_parse.h"
  77 #include "gallivm/lp_bld_type.h"
  78 #include "gallivm/lp_bld_const.h"
  79 #include "gallivm/lp_bld_conv.h"
  80 #include "gallivm/lp_bld_intr.h"
  81 #include "gallivm/lp_bld_logic.h"
  82 #include "gallivm/lp_bld_tgsi.h"
  83 #include "gallivm/lp_bld_swizzle.h"
  84 #include "gallivm/lp_bld_flow.h"
  85 #include "gallivm/lp_bld_debug.h"
  86
  87 #include "lp_bld_alpha.h"
  88 #include "lp_bld_blend.h"
  89 #include "lp_bld_depth.h"
  90 #include "lp_bld_interp.h"
  91 #include "lp_context.h"
  92 #include "lp_debug.h"
  93 #include "lp_perf.h"
  94 #include "lp_screen.h"
  95 #include "lp_setup.h"
  96 #include "lp_state.h"
  97 #include "lp_tex_sample.h"
  98
  99
 100 #include <llvm-c/Analysis.h>
 101
 102
 103 static unsigned fs_no = 0;
 104
 105
 106 /**
 107  * Generate the depth /stencil test code.
 108  */
 109 static void
 110 generate_depth_stencil(LLVMBuilderRef builder,
 111                        const struct lp_fragment_shader_variant_key *key,
 112                        struct lp_type src_type,
 113                        struct lp_build_mask_context *mask,
 114                        LLVMValueRef stencil_refs[2],
 115                        LLVMValueRef src,
 116                        LLVMValueRef dst_ptr,
 117                        LLVMValueRef facing,
 118                        LLVMValueRef counter)
 119 {
 120    const struct util_format_description *format_desc;
 121    struct lp_type dst_type;
 122
 123    if (!key->depth.enabled && !key->stencil[0].enabled && !key->stencil[1].enabled)
 124       return;
 125
 126    format_desc = util_format_description(key->zsbuf_format);
 127    assert(format_desc);
 128
 129    /*
 130     * Depths are expected to be between 0 and 1, even if they are stored in
 131     * floats. Setting these bits here will ensure that the lp_build_conv() call
 132     * below won't try to unnecessarily clamp the incoming values.
 133     */
 134    if(src_type.floating) {
 135       src_type.sign = FALSE;
 136       src_type.norm = TRUE;
 137    }
 138    else {
 139       assert(!src_type.sign);
 140       assert(src_type.norm);
 141    }
 142
 143    /* Pick the depth type. */
 144    dst_type = lp_depth_type(format_desc, src_type.width*src_type.length);
 145
 146    /* FIXME: Cope with a depth test type with a different bit width. */
 147    assert(dst_type.width == src_type.width);
 148    assert(dst_type.length == src_type.length);
 149
 150    /* Convert fragment Z from float to integer */
 151    lp_build_conv(builder, src_type, dst_type, &src, 1, &src, 1);
 152
 153    dst_ptr = LLVMBuildBitCast(builder,
 154                               dst_ptr,
 155                               LLVMPointerType(lp_build_vec_type(dst_type), 0), "");
 156    lp_build_depth_stencil_test(builder,
 157                                &key->depth,
 158                                key->stencil,
 159                                dst_type,
 160                                format_desc,
 161                                mask,
 162                                stencil_refs,
 163                                src,
 164                                dst_ptr,
 165                                facing,
 166                                counter);
 167 }
 168
 169
 170 /**
 171  * Generate the code to do inside/outside triangle testing for the
 172  * four pixels in a 2x2 quad.  This will set the four elements of the
 173  * quad mask vector to 0 or ~0.
 174  * \param i  which quad of the quad group to test, in [0,3]
 175  */
 176 static void
 177 generate_tri_edge_mask(LLVMBuilderRef builder,
 178                        unsigned i,
 179                        LLVMValueRef *mask,      /* ivec4, out */
 180                        LLVMValueRef c0,         /* int32 */
 181                        LLVMValueRef c1,         /* int32 */
 182                        LLVMValueRef c2,         /* int32 */
 183                        LLVMValueRef step0_ptr,  /* ivec4 */
 184                        LLVMValueRef step1_ptr,  /* ivec4 */
 185                        LLVMValueRef step2_ptr)  /* ivec4 */
 186 {
 187 #define OPTIMIZE_IN_OUT_TEST 0
 188 #if OPTIMIZE_IN_OUT_TEST
 189    struct lp_build_if_state ifctx;
 190    LLVMValueRef not_draw_all;
 191 #endif
 192    struct lp_build_flow_context *flow;
 193    struct lp_type i32_type;
 194    LLVMTypeRef i32vec4_type;
 195    LLVMValueRef c0_vec, c1_vec, c2_vec;
 196    LLVMValueRef in_out_mask;
 197
 198    assert(i < 4);
 199
 200    /* int32 vector type */
 201    memset(&i32_type, 0, sizeof i32_type);
 202    i32_type.floating = FALSE; /* values are integers */
 203    i32_type.sign = TRUE;      /* values are signed */
 204    i32_type.norm = FALSE;     /* values are not normalized */
 205    i32_type.width = 32;       /* 32-bit int values */
 206    i32_type.length = 4;       /* 4 elements per vector */
 207
 208    i32vec4_type = lp_build_int32_vec4_type();
 209
 210    /*
 211     * Use a conditional here to do detailed pixel in/out testing.
 212     * We only have to do this if c0 != INT_MIN.
 213     */
 214    flow = lp_build_flow_create(builder);
 215    lp_build_flow_scope_begin(flow);
 216
 217    {
 218 #if OPTIMIZE_IN_OUT_TEST
 219       /* not_draw_all = (c0 != INT_MIN) */
 220       not_draw_all = LLVMBuildICmp(builder,
 221                                    LLVMIntNE,
 222                                    c0,
 223                                    LLVMConstInt(LLVMInt32Type(), INT_MIN, 0),
 224                                    "");
 225
 226       in_out_mask = lp_build_const_int_vec(i32_type, ~0);
 227
 228
 229       lp_build_flow_scope_declare(flow, &in_out_mask);
 230
 231       /* if (not_draw_all) {... */
 232       lp_build_if(&ifctx, flow, builder, not_draw_all);
 233 #endif
 234       {
 235          LLVMValueRef step0_vec, step1_vec, step2_vec;
 236          LLVMValueRef m0_vec, m1_vec, m2_vec;
 237          LLVMValueRef index, m;
 238
 239          /* c0_vec = {c0, c0, c0, c0}
 240           * Note that we emit this code four times but LLVM optimizes away
 241           * three instances of it.
 242           */
 243          c0_vec = lp_build_broadcast(builder, i32vec4_type, c0);
 244          c1_vec = lp_build_broadcast(builder, i32vec4_type, c1);
 245          c2_vec = lp_build_broadcast(builder, i32vec4_type, c2);
 246          lp_build_name(c0_vec, "edgeconst0vec");
 247          lp_build_name(c1_vec, "edgeconst1vec");
 248          lp_build_name(c2_vec, "edgeconst2vec");
 249
 250          /* load step0vec, step1, step2 vec from memory */
 251          index = LLVMConstInt(LLVMInt32Type(), i, 0);
 252          step0_vec = LLVMBuildLoad(builder, LLVMBuildGEP(builder, step0_ptr, &index, 1, ""), "");
 253          step1_vec = LLVMBuildLoad(builder, LLVMBuildGEP(builder, step1_ptr, &index, 1, ""), "");
 254          step2_vec = LLVMBuildLoad(builder, LLVMBuildGEP(builder, step2_ptr, &index, 1, ""), "");
 255          lp_build_name(step0_vec, "step0vec");
 256          lp_build_name(step1_vec, "step1vec");
 257          lp_build_name(step2_vec, "step2vec");
 258
 259          /* m0_vec = step0_ptr[i] > c0_vec */
 260          m0_vec = lp_build_compare(builder, i32_type, PIPE_FUNC_GREATER, step0_vec, c0_vec);
 261          m1_vec = lp_build_compare(builder, i32_type, PIPE_FUNC_GREATER, step1_vec, c1_vec);
 262          m2_vec = lp_build_compare(builder, i32_type, PIPE_FUNC_GREATER, step2_vec, c2_vec);
 263
 264          /* in_out_mask = m0_vec & m1_vec & m2_vec */
 265          m = LLVMBuildAnd(builder, m0_vec, m1_vec, "");
 266          in_out_mask = LLVMBuildAnd(builder, m, m2_vec, "");
 267          lp_build_name(in_out_mask, "inoutmaskvec");
 268       }
 269 #if OPTIMIZE_IN_OUT_TEST
 270       lp_build_endif(&ifctx);
 271 #endif
 272
 273    }
 274    lp_build_flow_scope_end(flow);
 275    lp_build_flow_destroy(flow);
 276
 277    /* This is the initial alive/dead pixel mask for a quad of four pixels.
 278     * It's an int[4] vector with each word set to 0 or ~0.
 279     * Words will get cleared when pixels faile the Z test, etc.
 280     */
 281    *mask = in_out_mask;
 282 }
 283
 284
 285 static LLVMValueRef
 286 generate_scissor_test(LLVMBuilderRef builder,
 287                       LLVMValueRef context_ptr,
 288                       const struct lp_build_interp_soa_context *interp,
 289                       struct lp_type type)
 290 {
 291    LLVMTypeRef vec_type = lp_build_vec_type(type);
 292    LLVMValueRef xpos = interp->pos[0], ypos = interp->pos[1];
 293    LLVMValueRef xmin, ymin, xmax, ymax;
 294    LLVMValueRef m0, m1, m2, m3, m;
 295
 296    /* xpos, ypos contain the window coords for the four pixels in the quad */
 297    assert(xpos);
 298    assert(ypos);
 299
 300    /* get the current scissor bounds, convert to vectors */
 301    xmin = lp_jit_context_scissor_xmin_value(builder, context_ptr);
 302    xmin = lp_build_broadcast(builder, vec_type, xmin);
 303
 304    ymin = lp_jit_context_scissor_ymin_value(builder, context_ptr);
 305    ymin = lp_build_broadcast(builder, vec_type, ymin);
 306
 307    xmax = lp_jit_context_scissor_xmax_value(builder, context_ptr);
 308    xmax = lp_build_broadcast(builder, vec_type, xmax);
 309
 310    ymax = lp_jit_context_scissor_ymax_value(builder, context_ptr);
 311    ymax = lp_build_broadcast(builder, vec_type, ymax);
 312
 313    /* compare the fragment's position coordinates against the scissor bounds */
 314    m0 = lp_build_compare(builder, type, PIPE_FUNC_GEQUAL, xpos, xmin);
 315    m1 = lp_build_compare(builder, type, PIPE_FUNC_GEQUAL, ypos, ymin);
 316    m2 = lp_build_compare(builder, type, PIPE_FUNC_LESS, xpos, xmax);
 317    m3 = lp_build_compare(builder, type, PIPE_FUNC_LESS, ypos, ymax);
 318
 319    /* AND all the masks together */
 320    m = LLVMBuildAnd(builder, m0, m1, "");
 321    m = LLVMBuildAnd(builder, m, m2, "");
 322    m = LLVMBuildAnd(builder, m, m3, "");
 323
 324    lp_build_name(m, "scissormask");
 325
 326    return m;
 327 }
 328
 329
 330 static LLVMValueRef
 331 build_int32_vec_const(int value)
 332 {
 333    struct lp_type i32_type;
 334
 335    memset(&i32_type, 0, sizeof i32_type);
 336    i32_type.floating = FALSE; /* values are integers */
 337    i32_type.sign = TRUE;      /* values are signed */
 338    i32_type.norm = FALSE;     /* values are not normalized */
 339    i32_type.width = 32;       /* 32-bit int values */
 340    i32_type.length = 4;       /* 4 elements per vector */
 341    return lp_build_const_int_vec(i32_type, value);
 342 }
 343
 344
 345
 346 /**
 347  * Generate the fragment shader, depth/stencil test, and alpha tests.
 348  * \param i  which quad in the tile, in range [0,3]
 349  * \param do_tri_test  if 1, do triangle edge in/out testing
 350  */
 351 static void
 352 generate_fs(struct llvmpipe_context *lp,
 353             struct lp_fragment_shader *shader,
 354             const struct lp_fragment_shader_variant_key *key,
 355             LLVMBuilderRef builder,
 356             struct lp_type type,
 357             LLVMValueRef context_ptr,
 358             unsigned i,
 359             const struct lp_build_interp_soa_context *interp,
 360             struct lp_build_sampler_soa *sampler,
 361             LLVMValueRef *pmask,
 362             LLVMValueRef (*color)[4],
 363             LLVMValueRef depth_ptr,
 364             LLVMValueRef facing,
 365             unsigned do_tri_test,
 366             LLVMValueRef c0,
 367             LLVMValueRef c1,
 368             LLVMValueRef c2,
 369             LLVMValueRef step0_ptr,
 370             LLVMValueRef step1_ptr,
 371             LLVMValueRef step2_ptr,
 372             LLVMValueRef counter)
 373 {
 374    const struct tgsi_token *tokens = shader->base.tokens;
 375    LLVMTypeRef vec_type;
 376    LLVMValueRef consts_ptr;
 377    LLVMValueRef outputs[PIPE_MAX_SHADER_OUTPUTS][NUM_CHANNELS];
 378    LLVMValueRef z = interp->pos[2];
 379    LLVMValueRef stencil_refs[2];
 380    struct lp_build_flow_context *flow;
 381    struct lp_build_mask_context mask;
 382    boolean early_depth_stencil_test;
 383    unsigned attrib;
 384    unsigned chan;
 385    unsigned cbuf;
 386
 387    assert(i < 4);
 388
 389    stencil_refs[0] = lp_jit_context_stencil_ref_front_value(builder, context_ptr);
 390    stencil_refs[1] = lp_jit_context_stencil_ref_back_value(builder, context_ptr);
 391
 392    vec_type = lp_build_vec_type(type);
 393
 394    consts_ptr = lp_jit_context_constants(builder, context_ptr);
 395
 396    flow = lp_build_flow_create(builder);
 397
 398    memset(outputs, 0, sizeof outputs);
 399
 400    lp_build_flow_scope_begin(flow);
 401
 402    /* Declare the color and z variables */
 403    for(cbuf = 0; cbuf < key->nr_cbufs; cbuf++) {
 404       for(chan = 0; chan < NUM_CHANNELS; ++chan) {
 405          color[cbuf][chan] = LLVMGetUndef(vec_type);
 406          lp_build_flow_scope_declare(flow, &color[cbuf][chan]);
 407       }
 408    }
 409    lp_build_flow_scope_declare(flow, &z);
 410
 411    /* do triangle edge testing */
 412    if (do_tri_test) {
 413       generate_tri_edge_mask(builder, i, pmask,
 414                              c0, c1, c2, step0_ptr, step1_ptr, step2_ptr);
 415    }
 416    else {
 417       *pmask = build_int32_vec_const(~0);
 418    }
 419
 420    /* 'mask' will control execution based on quad's pixel alive/killed state */
 421    lp_build_mask_begin(&mask, flow, type, *pmask);
 422
 423    if (key->scissor) {
 424       LLVMValueRef smask =
 425          generate_scissor_test(builder, context_ptr, interp, type);
 426       lp_build_mask_update(&mask, smask);
 427    }
 428
 429    early_depth_stencil_test =
 430       (key->depth.enabled || key->stencil[0].enabled) &&
 431       !key->alpha.enabled &&
 432       !shader->info.uses_kill &&
 433       !shader->info.writes_z;
 434
 435    if (early_depth_stencil_test)
 436       generate_depth_stencil(builder, key,
 437                              type, &mask,
 438                              stencil_refs, z, depth_ptr, facing, counter);
 439
 440    lp_build_tgsi_soa(builder, tokens, type, &mask,
 441                      consts_ptr, interp->pos, interp->inputs,
 442                      outputs, sampler, &shader->info);
 443
 444    /* loop over fragment shader outputs/results */
 445    for (attrib = 0; attrib < shader->info.num_outputs; ++attrib) {
 446       for(chan = 0; chan < NUM_CHANNELS; ++chan) {
 447          if(outputs[attrib][chan]) {
 448             LLVMValueRef out = LLVMBuildLoad(builder, outputs[attrib][chan], "");
 449             lp_build_name(out, "output%u.%u.%c", i, attrib, "xyzw"[chan]);
 450
 451             switch (shader->info.output_semantic_name[attrib]) {
 452             case TGSI_SEMANTIC_COLOR:
 453                {
 454                   unsigned cbuf = shader->info.output_semantic_index[attrib];
 455
 456                   lp_build_name(out, "color%u.%u.%c", i, attrib, "rgba"[chan]);
 457
 458                   /* Alpha test */
 459                   /* XXX: should the alpha reference value be passed separately? */
 460                   /* XXX: should only test the final assignment to alpha */
 461                   if(cbuf == 0 && chan == 3) {
 462                      LLVMValueRef alpha = out;
 463                      LLVMValueRef alpha_ref_value;
 464                      alpha_ref_value = lp_jit_context_alpha_ref_value(builder, context_ptr);
 465                      alpha_ref_value = lp_build_broadcast(builder, vec_type, alpha_ref_value);
 466                      lp_build_alpha_test(builder, &key->alpha, type,
 467                                          &mask, alpha, alpha_ref_value);
 468                   }
 469
 470                   color[cbuf][chan] = out;
 471                   break;
 472                }
 473
 474             case TGSI_SEMANTIC_POSITION:
 475                if(chan == 2)
 476                   z = out;
 477                break;
 478             }
 479          }
 480       }
 481    }
 482
 483    if (!early_depth_stencil_test)
 484       generate_depth_stencil(builder, key,
 485                              type, &mask,
 486                              stencil_refs, z, depth_ptr, facing, counter);
 487
 488    lp_build_mask_end(&mask);
 489
 490    lp_build_flow_scope_end(flow);
 491
 492    lp_build_flow_destroy(flow);
 493
 494    *pmask = mask.value;
 495
 496 }
 497
 498
 499 /**
 500  * Generate color blending and color output.
 501  * \param rt  the render target index (to index blend, colormask state)
 502  * \param type  the pixel color type
 503  * \param context_ptr  pointer to the runtime JIT context
 504  * \param mask  execution mask (active fragment/pixel mask)
 505  * \param src  colors from the fragment shader
 506  * \param dst_ptr  the destination color buffer pointer
 507  */
 508 static void
 509 generate_blend(const struct pipe_blend_state *blend,
 510                unsigned rt,
 511                LLVMBuilderRef builder,
 512                struct lp_type type,
 513                LLVMValueRef context_ptr,
 514                LLVMValueRef mask,
 515                LLVMValueRef *src,
 516                LLVMValueRef dst_ptr)
 517 {
 518    struct lp_build_context bld;
 519    struct lp_build_flow_context *flow;
 520    struct lp_build_mask_context mask_ctx;
 521    LLVMTypeRef vec_type;
 522    LLVMValueRef const_ptr;
 523    LLVMValueRef con[4];
 524    LLVMValueRef dst[4];
 525    LLVMValueRef res[4];
 526    unsigned chan;
 527
 528    lp_build_context_init(&bld, builder, type);
 529
 530    flow = lp_build_flow_create(builder);
 531
 532    /* we'll use this mask context to skip blending if all pixels are dead */
 533    lp_build_mask_begin(&mask_ctx, flow, type, mask);
 534
 535    vec_type = lp_build_vec_type(type);
 536
 537    const_ptr = lp_jit_context_blend_color(builder, context_ptr);
 538    const_ptr = LLVMBuildBitCast(builder, const_ptr,
 539                                 LLVMPointerType(vec_type, 0), "");
 540
 541    /* load constant blend color and colors from the dest color buffer */
 542    for(chan = 0; chan < 4; ++chan) {
 543       LLVMValueRef index = LLVMConstInt(LLVMInt32Type(), chan, 0);
 544       con[chan] = LLVMBuildLoad(builder, LLVMBuildGEP(builder, const_ptr, &index, 1, ""), "");
 545
 546       dst[chan] = LLVMBuildLoad(builder, LLVMBuildGEP(builder, dst_ptr, &index, 1, ""), "");
 547
 548       lp_build_name(con[chan], "con.%c", "rgba"[chan]);
 549       lp_build_name(dst[chan], "dst.%c", "rgba"[chan]);
 550    }
 551
 552    /* do blend */
 553    lp_build_blend_soa(builder, blend, type, rt, src, dst, con, res);
 554
 555    /* store results to color buffer */
 556    for(chan = 0; chan < 4; ++chan) {
 557       if(blend->rt[rt].colormask & (1 << chan)) {
 558          LLVMValueRef index = LLVMConstInt(LLVMInt32Type(), chan, 0);
 559          lp_build_name(res[chan], "res.%c", "rgba"[chan]);
 560          res[chan] = lp_build_select(&bld, mask, res[chan], dst[chan]);
 561          LLVMBuildStore(builder, res[chan], LLVMBuildGEP(builder, dst_ptr, &index, 1, ""));
 562       }
 563    }
 564
 565    lp_build_mask_end(&mask_ctx);
 566    lp_build_flow_destroy(flow);
 567 }
 568
 569
 570 /**
 571  * Generate the runtime callable function for the whole fragment pipeline.
 572  * Note that the function which we generate operates on a block of 16
 573  * pixels at at time.  The block contains 2x2 quads.  Each quad contains
 574  * 2x2 pixels.
 575  */
 576 static void
 577 generate_fragment(struct llvmpipe_context *lp,
 578                   struct lp_fragment_shader *shader,
 579                   struct lp_fragment_shader_variant *variant,
 580                   unsigned do_tri_test)
 581 {
 582    struct llvmpipe_screen *screen = llvmpipe_screen(lp->pipe.screen);
 583    const struct lp_fragment_shader_variant_key *key = &variant->key;
 584    char func_name[256];
 585    struct lp_type fs_type;
 586    struct lp_type blend_type;
 587    LLVMTypeRef fs_elem_type;
 588    LLVMTypeRef fs_int_vec_type;
 589    LLVMTypeRef blend_vec_type;
 590    LLVMTypeRef arg_types[16];
 591    LLVMTypeRef func_type;
 592    LLVMTypeRef int32_vec4_type = lp_build_int32_vec4_type();
 593    LLVMValueRef context_ptr;
 594    LLVMValueRef x;
 595    LLVMValueRef y;
 596    LLVMValueRef a0_ptr;
 597    LLVMValueRef dadx_ptr;
 598    LLVMValueRef dady_ptr;
 599    LLVMValueRef color_ptr_ptr;
 600    LLVMValueRef depth_ptr;
 601    LLVMValueRef c0, c1, c2, step0_ptr, step1_ptr, step2_ptr, counter = NULL;
 602    LLVMBasicBlockRef block;
 603    LLVMBuilderRef builder;
 604    struct lp_build_sampler_soa *sampler;
 605    struct lp_build_interp_soa_context interp;
 606    LLVMValueRef fs_mask[LP_MAX_VECTOR_LENGTH];
 607    LLVMValueRef fs_out_color[PIPE_MAX_COLOR_BUFS][NUM_CHANNELS][LP_MAX_VECTOR_LENGTH];
 608    LLVMValueRef blend_mask;
 609    LLVMValueRef function;
 610    LLVMValueRef facing;
 611    unsigned num_fs;
 612    unsigned i;
 613    unsigned chan;
 614    unsigned cbuf;
 615
 616
 617    /* TODO: actually pick these based on the fs and color buffer
 618     * characteristics. */
 619
 620    memset(&fs_type, 0, sizeof fs_type);
 621    fs_type.floating = TRUE; /* floating point values */
 622    fs_type.sign = TRUE;     /* values are signed */
 623    fs_type.norm = FALSE;    /* values are not limited to [0,1] or [-1,1] */
 624    fs_type.width = 32;      /* 32-bit float */
 625    fs_type.length = 4;      /* 4 elements per vector */
 626    num_fs = 4;              /* number of quads per block */
 627
 628    memset(&blend_type, 0, sizeof blend_type);
 629    blend_type.floating = FALSE; /* values are integers */
 630    blend_type.sign = FALSE;     /* values are unsigned */
 631    blend_type.norm = TRUE;      /* values are in [0,1] or [-1,1] */
 632    blend_type.width = 8;        /* 8-bit ubyte values */
 633    blend_type.length = 16;      /* 16 elements per vector */
 634
 635    /*
 636     * Generate the function prototype. Any change here must be reflected in
 637     * lp_jit.h's lp_jit_frag_func function pointer type, and vice-versa.
 638     */
 639
 640    fs_elem_type = lp_build_elem_type(fs_type);
 641    fs_int_vec_type = lp_build_int_vec_type(fs_type);
 642
 643    blend_vec_type = lp_build_vec_type(blend_type);
 644
 645    util_snprintf(func_name, sizeof(func_name), "fs%u_variant%u_%s",
 646                  shader->no, variant->no, do_tri_test ? "edge" : "whole");
 647
 648    arg_types[0] = screen->context_ptr_type;            /* context */
 649    arg_types[1] = LLVMInt32Type();                     /* x */
 650    arg_types[2] = LLVMInt32Type();                     /* y */
 651    arg_types[3] = LLVMFloatType();                     /* facing */
 652    arg_types[4] = LLVMPointerType(fs_elem_type, 0);    /* a0 */
 653    arg_types[5] = LLVMPointerType(fs_elem_type, 0);    /* dadx */
 654    arg_types[6] = LLVMPointerType(fs_elem_type, 0);    /* dady */
 655    arg_types[7] = LLVMPointerType(LLVMPointerType(blend_vec_type, 0), 0);  /* color */
 656    arg_types[8] = LLVMPointerType(fs_int_vec_type, 0); /* depth */
 657    arg_types[9] = LLVMInt32Type();                     /* c0 */
 658    arg_types[10] = LLVMInt32Type();                    /* c1 */
 659    arg_types[11] = LLVMInt32Type();                    /* c2 */
 660    /* Note: the step arrays are built as int32[16] but we interpret
 661     * them here as int32_vec4[4].
 662     */
 663    arg_types[12] = LLVMPointerType(int32_vec4_type, 0);/* step0 */
 664    arg_types[13] = LLVMPointerType(int32_vec4_type, 0);/* step1 */
 665    arg_types[14] = LLVMPointerType(int32_vec4_type, 0);/* step2 */
 666    arg_types[15] = LLVMPointerType(LLVMInt32Type(), 0);/* counter */
 667
 668    func_type = LLVMFunctionType(LLVMVoidType(), arg_types, Elements(arg_types), 0);
 669
 670    function = LLVMAddFunction(screen->module, func_name, func_type);
 671    LLVMSetFunctionCallConv(function, LLVMCCallConv);
 672
 673    variant->function[do_tri_test] = function;
 674
 675
 676    /* XXX: need to propagate noalias down into color param now we are
 677     * passing a pointer-to-pointer?
 678     */
 679    for(i = 0; i < Elements(arg_types); ++i)
 680       if(LLVMGetTypeKind(arg_types[i]) == LLVMPointerTypeKind)
 681          LLVMAddAttribute(LLVMGetParam(function, i), LLVMNoAliasAttribute);
 682
 683    context_ptr  = LLVMGetParam(function, 0);
 684    x            = LLVMGetParam(function, 1);
 685    y            = LLVMGetParam(function, 2);
 686    facing       = LLVMGetParam(function, 3);
 687    a0_ptr       = LLVMGetParam(function, 4);
 688    dadx_ptr     = LLVMGetParam(function, 5);
 689    dady_ptr     = LLVMGetParam(function, 6);
 690    color_ptr_ptr = LLVMGetParam(function, 7);
 691    depth_ptr    = LLVMGetParam(function, 8);
 692    c0           = LLVMGetParam(function, 9);
 693    c1           = LLVMGetParam(function, 10);
 694    c2           = LLVMGetParam(function, 11);
 695    step0_ptr    = LLVMGetParam(function, 12);
 696    step1_ptr    = LLVMGetParam(function, 13);
 697    step2_ptr    = LLVMGetParam(function, 14);
 698
 699    lp_build_name(context_ptr, "context");
 700    lp_build_name(x, "x");
 701    lp_build_name(y, "y");
 702    lp_build_name(a0_ptr, "a0");
 703    lp_build_name(dadx_ptr, "dadx");
 704    lp_build_name(dady_ptr, "dady");
 705    lp_build_name(color_ptr_ptr, "color_ptr_ptr");
 706    lp_build_name(depth_ptr, "depth");
 707    lp_build_name(c0, "c0");
 708    lp_build_name(c1, "c1");
 709    lp_build_name(c2, "c2");
 710    lp_build_name(step0_ptr, "step0");
 711    lp_build_name(step1_ptr, "step1");
 712    lp_build_name(step2_ptr, "step2");
 713
 714    if (key->occlusion_count) {
 715       counter = LLVMGetParam(function, 15);
 716       lp_build_name(counter, "counter");
 717    }
 718
 719    /*
 720     * Function body
 721     */
 722
 723    block = LLVMAppendBasicBlock(function, "entry");
 724    builder = LLVMCreateBuilder();
 725    LLVMPositionBuilderAtEnd(builder, block);
 726
 727    /*
 728     * The shader input interpolation info is not explicitely baked in the
 729     * shader key, but everything it derives from (TGSI, and flatshade) is
 730     * already included in the shader key.
 731     */
 732    lp_build_interp_soa_init(&interp,
 733                             lp->num_inputs,
 734                             lp->inputs,
 735                             builder, fs_type,
 736                             a0_ptr, dadx_ptr, dady_ptr,
 737                             x, y);
 738
 739    /* code generated texture sampling */
 740    sampler = lp_llvm_sampler_soa_create(key->sampler, context_ptr);
 741
 742    /* loop over quads in the block */
 743    for(i = 0; i < num_fs; ++i) {
 744       LLVMValueRef index = LLVMConstInt(LLVMInt32Type(), i, 0);
 745       LLVMValueRef out_color[PIPE_MAX_COLOR_BUFS][NUM_CHANNELS];
 746       LLVMValueRef depth_ptr_i;
 747
 748       if(i != 0)
 749          lp_build_interp_soa_update(&interp, i);
 750
 751       depth_ptr_i = LLVMBuildGEP(builder, depth_ptr, &index, 1, "");
 752
 753       generate_fs(lp, shader, key,
 754                   builder,
 755                   fs_type,
 756                   context_ptr,
 757                   i,
 758                   &interp,
 759                   sampler,
 760                   &fs_mask[i], /* output */
 761                   out_color,
 762                   depth_ptr_i,
 763                   facing,
 764                   do_tri_test,
 765                   c0, c1, c2,
 766                   step0_ptr, step1_ptr, step2_ptr, counter);
 767
 768       for(cbuf = 0; cbuf < key->nr_cbufs; cbuf++)
 769          for(chan = 0; chan < NUM_CHANNELS; ++chan)
 770             fs_out_color[cbuf][chan][i] = out_color[cbuf][chan];
 771    }
 772
 773    sampler->destroy(sampler);
 774
 775    /* Loop over color outputs / color buffers to do blending.
 776     */
 777    for(cbuf = 0; cbuf < key->nr_cbufs; cbuf++) {
 778       LLVMValueRef color_ptr;
 779       LLVMValueRef index = LLVMConstInt(LLVMInt32Type(), cbuf, 0);
 780       LLVMValueRef blend_in_color[NUM_CHANNELS];
 781       unsigned rt;
 782
 783       /*
 784        * Convert the fs's output color and mask to fit to the blending type.
 785        */
 786       for(chan = 0; chan < NUM_CHANNELS; ++chan) {
 787          lp_build_conv(builder, fs_type, blend_type,
 788                        fs_out_color[cbuf][chan], num_fs,
 789                        &blend_in_color[chan], 1);
 790          lp_build_name(blend_in_color[chan], "color%d.%c", cbuf, "rgba"[chan]);
 791       }
 792
 793       lp_build_conv_mask(builder, fs_type, blend_type,
 794                          fs_mask, num_fs,
 795                          &blend_mask, 1);
 796
 797       color_ptr = LLVMBuildLoad(builder,
 798                                 LLVMBuildGEP(builder, color_ptr_ptr, &index, 1, ""),
 799                                 "");
 800       lp_build_name(color_ptr, "color_ptr%d", cbuf);
 801
 802       /* which blend/colormask state to use */
 803       rt = key->blend.independent_blend_enable ? cbuf : 0;
 804
 805       /*
 806        * Blending.
 807        */
 808       generate_blend(&key->blend,
 809                      rt,
 810                      builder,
 811                      blend_type,
 812                      context_ptr,
 813                      blend_mask,
 814                      blend_in_color,
 815                      color_ptr);
 816    }
 817
 818    LLVMBuildRetVoid(builder);
 819
 820    LLVMDisposeBuilder(builder);
 821
 822
 823    /* Verify the LLVM IR.  If invalid, dump and abort */
 824 #ifdef DEBUG
 825    if(LLVMVerifyFunction(function, LLVMPrintMessageAction)) {
 826       if (1)
 827          lp_debug_dump_value(function);
 828       abort();
 829    }
 830 #endif
 831
 832    /* Apply optimizations to LLVM IR */
 833    if (1)
 834       LLVMRunFunctionPassManager(screen->pass, function);
 835
 836    if (gallivm_debug & GALLIVM_DEBUG_IR) {
 837       /* Print the LLVM IR to stderr */
 838       lp_debug_dump_value(function);
 839       debug_printf("\n");
 840    }
 841
 842    /*
 843     * Translate the LLVM IR into machine code.
 844     */
 845    {
 846       void *f = LLVMGetPointerToGlobal(screen->engine, function);
 847
 848       variant->jit_function[do_tri_test] = (lp_jit_frag_func)pointer_to_func(f);
 849
 850       if (gallivm_debug & GALLIVM_DEBUG_ASM) {
 851          lp_disassemble(f);
 852       }
 853    }
 854 }
 855
 856
 857 static void
 858 dump_fs_variant_key(const struct lp_fragment_shader_variant_key *key)
 859 {
 860    unsigned i;
 861
 862    debug_printf("fs variant %p:\n", (void *) key);
 863
 864    if (key->depth.enabled) {
 865       debug_printf("depth.format = %s\n", util_format_name(key->zsbuf_format));
 866       debug_printf("depth.func = %s\n", util_dump_func(key->depth.func, TRUE));
 867       debug_printf("depth.writemask = %u\n", key->depth.writemask);
 868    }
 869
 870    for (i = 0; i < 2; ++i) {
 871       if (key->stencil[i].enabled) {
 872          debug_printf("stencil[%u].func = %s\n", i, util_dump_func(key->stencil[i].func, TRUE));
 873          debug_printf("stencil[%u].fail_op = %s\n", i, util_dump_stencil_op(key->stencil[i].fail_op, TRUE));
 874          debug_printf("stencil[%u].zpass_op = %s\n", i, util_dump_stencil_op(key->stencil[i].zpass_op, TRUE));
 875          debug_printf("stencil[%u].zfail_op = %s\n", i, util_dump_stencil_op(key->stencil[i].zfail_op, TRUE));
 876          debug_printf("stencil[%u].valuemask = 0x%x\n", i, key->stencil[i].valuemask);
 877          debug_printf("stencil[%u].writemask = 0x%x\n", i, key->stencil[i].writemask);
 878       }
 879    }
 880
 881    if (key->alpha.enabled) {
 882       debug_printf("alpha.func = %s\n", util_dump_func(key->alpha.func, TRUE));
 883       debug_printf("alpha.ref_value = %f\n", key->alpha.ref_value);
 884    }
 885
 886    if (key->blend.logicop_enable) {
 887       debug_printf("blend.logicop_func = %s\n", util_dump_logicop(key->blend.logicop_func, TRUE));
 888    }
 889    else if (key->blend.rt[0].blend_enable) {
 890       debug_printf("blend.rgb_func = %s\n",   util_dump_blend_func  (key->blend.rt[0].rgb_func, TRUE));
 891       debug_printf("blend.rgb_src_factor = %s\n",   util_dump_blend_factor(key->blend.rt[0].rgb_src_factor, TRUE));
 892       debug_printf("blend.rgb_dst_factor = %s\n",   util_dump_blend_factor(key->blend.rt[0].rgb_dst_factor, TRUE));
 893       debug_printf("blend.alpha_func = %s\n",       util_dump_blend_func  (key->blend.rt[0].alpha_func, TRUE));
 894       debug_printf("blend.alpha_src_factor = %s\n", util_dump_blend_factor(key->blend.rt[0].alpha_src_factor, TRUE));
 895       debug_printf("blend.alpha_dst_factor = %s\n", util_dump_blend_factor(key->blend.rt[0].alpha_dst_factor, TRUE));
 896    }
 897    debug_printf("blend.colormask = 0x%x\n", key->blend.rt[0].colormask);
 898    for (i = 0; i < PIPE_MAX_SAMPLERS; ++i) {
 899       if (key->sampler[i].format) {
 900          debug_printf("sampler[%u] = \n", i);
 901          debug_printf("  .format = %s\n",
 902                       util_format_name(key->sampler[i].format));
 903          debug_printf("  .target = %s\n",
 904                       util_dump_tex_target(key->sampler[i].target, TRUE));
 905          debug_printf("  .pot = %u %u %u\n",
 906                       key->sampler[i].pot_width,
 907                       key->sampler[i].pot_height,
 908                       key->sampler[i].pot_depth);
 909          debug_printf("  .wrap = %s %s %s\n",
 910                       util_dump_tex_wrap(key->sampler[i].wrap_s, TRUE),
 911                       util_dump_tex_wrap(key->sampler[i].wrap_t, TRUE),
 912                       util_dump_tex_wrap(key->sampler[i].wrap_r, TRUE));
 913          debug_printf("  .min_img_filter = %s\n",
 914                       util_dump_tex_filter(key->sampler[i].min_img_filter, TRUE));
 915          debug_printf("  .min_mip_filter = %s\n",
 916                       util_dump_tex_mipfilter(key->sampler[i].min_mip_filter, TRUE));
 917          debug_printf("  .mag_img_filter = %s\n",
 918                       util_dump_tex_filter(key->sampler[i].mag_img_filter, TRUE));
 919          if (key->sampler[i].compare_mode != PIPE_TEX_COMPARE_NONE)
 920             debug_printf("  .compare_func = %s\n", util_dump_func(key->sampler[i].compare_func, TRUE));
 921          debug_printf("  .normalized_coords = %u\n", key->sampler[i].normalized_coords);
 922       }
 923    }
 924 }
 925
 926
 927
 928 static struct lp_fragment_shader_variant *
 929 generate_variant(struct llvmpipe_context *lp,
 930                  struct lp_fragment_shader *shader,
 931                  const struct lp_fragment_shader_variant_key *key)
 932 {
 933    struct lp_fragment_shader_variant *variant;
 934
 935    variant = CALLOC_STRUCT(lp_fragment_shader_variant);
 936    if(!variant)
 937       return NULL;
 938
 939    variant->no = shader->variant_no++;
 940
 941    memcpy(&variant->key, key, sizeof *key);
 942
 943    if (gallivm_debug & GALLIVM_DEBUG_IR) {
 944       debug_printf("llvmpipe: Creating fragment shader #%u variant #%u:\n",
 945                    shader->no, variant->no);
 946       tgsi_dump(shader->base.tokens, 0);
 947       dump_fs_variant_key(key);
 948    }
 949
 950    generate_fragment(lp, shader, variant, RAST_WHOLE);
 951    generate_fragment(lp, shader, variant, RAST_EDGE_TEST);
 952
 953    /* TODO: most of these can be relaxed, in particular the colormask */
 954    variant->opaque =
 955          !key->blend.logicop_enable &&
 956          !key->blend.rt[0].blend_enable &&
 957          key->blend.rt[0].colormask == 0xf &&
 958          !key->stencil[0].enabled &&
 959          !key->alpha.enabled &&
 960          !key->depth.enabled &&
 961          !key->scissor &&
 962          !shader->info.uses_kill
 963          ? TRUE : FALSE;
 964
 965    /* insert new variant into linked list */
 966    variant->next = shader->variants;
 967    shader->variants = variant;
 968
 969    return variant;
 970 }
 971
 972
 973 static void *
 974 llvmpipe_create_fs_state(struct pipe_context *pipe,
 975                          const struct pipe_shader_state *templ)
 976 {
 977    struct lp_fragment_shader *shader;
 978
 979    shader = CALLOC_STRUCT(lp_fragment_shader);
 980    if (!shader)
 981       return NULL;
 982
 983    shader->no = fs_no++;
 984
 985    /* get/save the summary info for this shader */
 986    tgsi_scan_shader(templ->tokens, &shader->info);
 987
 988    /* we need to keep a local copy of the tokens */
 989    shader->base.tokens = tgsi_dup_tokens(templ->tokens);
 990
 991    if (LP_DEBUG & DEBUG_TGSI) {
 992       unsigned attrib;
 993       debug_printf("llvmpipe: Create fragment shader #%u %p:\n", shader->no, (void *) shader);
 994       tgsi_dump(templ->tokens, 0);
 995       debug_printf("usage masks:\n");
 996       for (attrib = 0; attrib < shader->info.num_inputs; ++attrib) {
 997          unsigned usage_mask = shader->info.input_usage_mask[attrib];
 998          debug_printf("  IN[%u].%s%s%s%s\n",
 999                       attrib,
1000                       usage_mask & TGSI_WRITEMASK_X ? "x" : "",
1001                       usage_mask & TGSI_WRITEMASK_Y ? "y" : "",
1002                       usage_mask & TGSI_WRITEMASK_Z ? "z" : "",
1003                       usage_mask & TGSI_WRITEMASK_W ? "w" : "");
1004       }
1005       debug_printf("\n");
1006    }
1007
1008    return shader;
1009 }
1010
1011
1012 static void
1013 llvmpipe_bind_fs_state(struct pipe_context *pipe, void *fs)
1014 {
1015    struct llvmpipe_context *llvmpipe = llvmpipe_context(pipe);
1016
1017    if (llvmpipe->fs == fs)
1018       return;
1019
1020    draw_flush(llvmpipe->draw);
1021
1022    llvmpipe->fs = fs;
1023
1024    llvmpipe->dirty |= LP_NEW_FS;
1025 }
1026
1027
1028 static void
1029 llvmpipe_delete_fs_state(struct pipe_context *pipe, void *fs)
1030 {
1031    struct llvmpipe_context *llvmpipe = llvmpipe_context(pipe);
1032    struct llvmpipe_screen *screen = llvmpipe_screen(pipe->screen);
1033    struct lp_fragment_shader *shader = fs;
1034    struct lp_fragment_shader_variant *variant;
1035
1036    assert(fs != llvmpipe->fs);
1037    (void) llvmpipe;
1038
1039    /*
1040     * XXX: we need to flush the context until we have some sort of reference
1041     * counting in fragment shaders as they may still be binned
1042     */
1043    draw_flush(llvmpipe->draw);
1044    lp_setup_flush(llvmpipe->setup, 0);
1045
1046    variant = shader->variants;
1047    while(variant) {
1048       struct lp_fragment_shader_variant *next = variant->next;
1049       unsigned i;
1050
1051       for (i = 0; i < Elements(variant->function); i++) {
1052          if (variant->function[i]) {
1053             if (variant->jit_function[i])
1054                LLVMFreeMachineCodeForFunction(screen->engine,
1055                                               variant->function[i]);
1056             LLVMDeleteFunction(variant->function[i]);
1057          }
1058       }
1059
1060       FREE(variant);
1061
1062       variant = next;
1063    }
1064
1065    FREE((void *) shader->base.tokens);
1066    FREE(shader);
1067 }
1068
1069
1070
1071 static void
1072 llvmpipe_set_constant_buffer(struct pipe_context *pipe,
1073                              uint shader, uint index,
1074                              struct pipe_resource *constants)
1075 {
1076    struct llvmpipe_context *llvmpipe = llvmpipe_context(pipe);
1077    unsigned size = constants ? constants->width0 : 0;
1078    const void *data = constants ? llvmpipe_resource_data(constants) : NULL;
1079
1080    assert(shader < PIPE_SHADER_TYPES);
1081    assert(index < PIPE_MAX_CONSTANT_BUFFERS);
1082
1083    if(llvmpipe->constants[shader][index] == constants)
1084       return;
1085
1086    draw_flush(llvmpipe->draw);
1087
1088    /* note: reference counting */
1089    pipe_resource_reference(&llvmpipe->constants[shader][index], constants);
1090
1091    if(shader == PIPE_SHADER_VERTEX) {
1092       draw_set_mapped_constant_buffer(llvmpipe->draw, PIPE_SHADER_VERTEX, index,
1093                                       data, size);
1094    }
1095
1096    llvmpipe->dirty |= LP_NEW_CONSTANTS;
1097 }
1098
1099
1100 /**
1101  * Return the blend factor equivalent to a destination alpha of one.
1102  */
1103 static INLINE unsigned
1104 force_dst_alpha_one(unsigned factor, boolean alpha)
1105 {
1106    switch(factor) {
1107    case PIPE_BLENDFACTOR_DST_ALPHA:
1108       return PIPE_BLENDFACTOR_ONE;
1109    case PIPE_BLENDFACTOR_INV_DST_ALPHA:
1110       return PIPE_BLENDFACTOR_ZERO;
1111    case PIPE_BLENDFACTOR_SRC_ALPHA_SATURATE:
1112       return PIPE_BLENDFACTOR_ZERO;
1113    }
1114
1115    if (alpha) {
1116       switch(factor) {
1117       case PIPE_BLENDFACTOR_DST_COLOR:
1118          return PIPE_BLENDFACTOR_ONE;
1119       case PIPE_BLENDFACTOR_INV_DST_COLOR:
1120          return PIPE_BLENDFACTOR_ZERO;
1121       }
1122    }
1123
1124    return factor;
1125 }
1126
1127
1128 /**
1129  * We need to generate several variants of the fragment pipeline to match
1130  * all the combinations of the contributing state atoms.
1131  *
1132  * TODO: there is actually no reason to tie this to context state -- the
1133  * generated code could be cached globally in the screen.
1134  */
1135 static void
1136 make_variant_key(struct llvmpipe_context *lp,
1137                  struct lp_fragment_shader *shader,
1138                  struct lp_fragment_shader_variant_key *key)
1139 {
1140    unsigned i;
1141
1142    memset(key, 0, sizeof *key);
1143
1144    if (lp->framebuffer.zsbuf) {
1145       if (lp->depth_stencil->depth.enabled) {
1146          key->zsbuf_format = lp->framebuffer.zsbuf->format;
1147          memcpy(&key->depth, &lp->depth_stencil->depth, sizeof key->depth);
1148       }
1149       if (lp->depth_stencil->stencil[0].enabled) {
1150          key->zsbuf_format = lp->framebuffer.zsbuf->format;
1151          memcpy(&key->stencil, &lp->depth_stencil->stencil, sizeof key->stencil);
1152       }
1153    }
1154
1155    key->alpha.enabled = lp->depth_stencil->alpha.enabled;
1156    if(key->alpha.enabled)
1157       key->alpha.func = lp->depth_stencil->alpha.func;
1158    /* alpha.ref_value is passed in jit_context */
1159
1160    key->flatshade = lp->rasterizer->flatshade;
1161    key->scissor = lp->rasterizer->scissor;
1162    if (lp->active_query_count) {
1163       key->occlusion_count = TRUE;
1164    }
1165
1166    if (lp->framebuffer.nr_cbufs) {
1167       memcpy(&key->blend, lp->blend, sizeof key->blend);
1168    }
1169
1170    key->nr_cbufs = lp->framebuffer.nr_cbufs;
1171    for (i = 0; i < lp->framebuffer.nr_cbufs; i++) {
1172       struct pipe_rt_blend_state *blend_rt = &key->blend.rt[i];
1173       const struct util_format_description *format_desc;
1174       unsigned chan;
1175
1176       format_desc = util_format_description(lp->framebuffer.cbufs[i]->format);
1177       assert(format_desc->colorspace == UTIL_FORMAT_COLORSPACE_RGB ||
1178              format_desc->colorspace == UTIL_FORMAT_COLORSPACE_SRGB);
1179
1180       blend_rt->colormask = lp->blend->rt[i].colormask;
1181
1182       /* mask out color channels not present in the color buffer.
1183        * Should be simple to incorporate per-cbuf writemasks:
1184        */
1185       for(chan = 0; chan < 4; ++chan) {
1186          enum util_format_swizzle swizzle = format_desc->swizzle[chan];
1187
1188          if(swizzle > UTIL_FORMAT_SWIZZLE_W)
1189             blend_rt->colormask &= ~(1 << chan);
1190       }
1191
1192       /*
1193        * Our swizzled render tiles always have an alpha channel, but the linear
1194        * render target format often does not, so force here the dst alpha to be
1195        * one.
1196        *
1197        * This is not a mere optimization. Wrong results will be produced if the
1198        * dst alpha is used, the dst format does not have alpha, and the previous
1199        * rendering was not flushed from the swizzled to linear buffer. For
1200        * example, NonPowTwo DCT.
1201        *
1202        * TODO: This should be generalized to all channels for better
1203        * performance, but only alpha causes correctness issues.
1204        */
1205       if (format_desc->swizzle[3] > UTIL_FORMAT_SWIZZLE_W) {
1206          blend_rt->rgb_src_factor = force_dst_alpha_one(blend_rt->rgb_src_factor, FALSE);
1207          blend_rt->rgb_dst_factor = force_dst_alpha_one(blend_rt->rgb_dst_factor, FALSE);
1208          blend_rt->alpha_src_factor = force_dst_alpha_one(blend_rt->alpha_src_factor, TRUE);
1209          blend_rt->alpha_dst_factor = force_dst_alpha_one(blend_rt->alpha_dst_factor, TRUE);
1210       }
1211    }
1212
1213    for(i = 0; i < PIPE_MAX_SAMPLERS; ++i)
1214       if(shader->info.file_mask[TGSI_FILE_SAMPLER] & (1 << i))
1215          lp_sampler_static_state(&key->sampler[i], lp->fragment_sampler_views[i], lp->sampler[i]);
1216 }
1217
1218
1219 /**
1220  * Update fragment state.  This is called just prior to drawing
1221  * something when some fragment-related state has changed.
1222  */
1223 void
1224 llvmpipe_update_fs(struct llvmpipe_context *lp)
1225 {
1226    struct lp_fragment_shader *shader = lp->fs;
1227    struct lp_fragment_shader_variant_key key;
1228    struct lp_fragment_shader_variant *variant;
1229
1230    make_variant_key(lp, shader, &key);
1231
1232    variant = shader->variants;
1233    while(variant) {
1234       if(memcmp(&variant->key, &key, sizeof key) == 0)
1235          break;
1236
1237       variant = variant->next;
1238    }
1239
1240    if (!variant) {
1241       int64_t t0, t1;
1242       int64_t dt;
1243       t0 = os_time_get();
1244
1245       variant = generate_variant(lp, shader, &key);
1246
1247       t1 = os_time_get();
1248       dt = t1 - t0;
1249       LP_COUNT_ADD(llvm_compile_time, dt);
1250       LP_COUNT_ADD(nr_llvm_compiles, 2);  /* emit vs. omit in/out test */
1251    }
1252
1253    lp_setup_set_fs_variant(lp->setup, variant);
1254 }
1255
1256
1257
1258 void
1259 llvmpipe_init_fs_funcs(struct llvmpipe_context *llvmpipe)
1260 {
1261    llvmpipe->pipe.create_fs_state = llvmpipe_create_fs_state;
1262    llvmpipe->pipe.bind_fs_state   = llvmpipe_bind_fs_state;
1263    llvmpipe->pipe.delete_fs_state = llvmpipe_delete_fs_state;
1264
1265    llvmpipe->pipe.set_constant_buffer = llvmpipe_set_constant_buffer;
1266 }