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 (stencil TBI)
  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_format.h"
  68 #include "util/u_dump.h"
  69 #include "os/os_time.h"
  70 #include "pipe/p_shader_tokens.h"
  71 #include "draw/draw_context.h"
  72 #include "tgsi/tgsi_dump.h"
  73 #include "tgsi/tgsi_scan.h"
  74 #include "tgsi/tgsi_parse.h"
  75 #include "gallivm/lp_bld_type.h"
  76 #include "gallivm/lp_bld_const.h"
  77 #include "gallivm/lp_bld_conv.h"
  78 #include "gallivm/lp_bld_intr.h"
  79 #include "gallivm/lp_bld_logic.h"
  80 #include "gallivm/lp_bld_depth.h"
  81 #include "gallivm/lp_bld_interp.h"
  82 #include "gallivm/lp_bld_tgsi.h"
  83 #include "gallivm/lp_bld_alpha.h"
  84 #include "gallivm/lp_bld_blend.h"
  85 #include "gallivm/lp_bld_swizzle.h"
  86 #include "gallivm/lp_bld_flow.h"
  87 #include "gallivm/lp_bld_debug.h"
  88 #include "lp_buffer.h"
  89 #include "lp_context.h"
  90 #include "lp_debug.h"
  91 #include "lp_perf.h"
  92 #include "lp_screen.h"
  93 #include "lp_setup.h"
  94 #include "lp_state.h"
  95 #include "lp_tex_sample.h"
  96
  97
  98 #include <llvm-c/Analysis.h>
  99
 100
 101 static const unsigned char quad_offset_x[4] = {0, 1, 0, 1};
 102 static const unsigned char quad_offset_y[4] = {0, 0, 1, 1};
 103
 104
 105 /*
 106  * Derive from the quad's upper left scalar coordinates the coordinates for
 107  * all other quad pixels
 108  */
 109 static void
 110 generate_pos0(LLVMBuilderRef builder,
 111               LLVMValueRef x,
 112               LLVMValueRef y,
 113               LLVMValueRef *x0,
 114               LLVMValueRef *y0)
 115 {
 116    LLVMTypeRef int_elem_type = LLVMInt32Type();
 117    LLVMTypeRef int_vec_type = LLVMVectorType(int_elem_type, QUAD_SIZE);
 118    LLVMTypeRef elem_type = LLVMFloatType();
 119    LLVMTypeRef vec_type = LLVMVectorType(elem_type, QUAD_SIZE);
 120    LLVMValueRef x_offsets[QUAD_SIZE];
 121    LLVMValueRef y_offsets[QUAD_SIZE];
 122    unsigned i;
 123
 124    x = lp_build_broadcast(builder, int_vec_type, x);
 125    y = lp_build_broadcast(builder, int_vec_type, y);
 126
 127    for(i = 0; i < QUAD_SIZE; ++i) {
 128       x_offsets[i] = LLVMConstInt(int_elem_type, quad_offset_x[i], 0);
 129       y_offsets[i] = LLVMConstInt(int_elem_type, quad_offset_y[i], 0);
 130    }
 131
 132    x = LLVMBuildAdd(builder, x, LLVMConstVector(x_offsets, QUAD_SIZE), "");
 133    y = LLVMBuildAdd(builder, y, LLVMConstVector(y_offsets, QUAD_SIZE), "");
 134
 135    *x0 = LLVMBuildSIToFP(builder, x, vec_type, "");
 136    *y0 = LLVMBuildSIToFP(builder, y, vec_type, "");
 137 }
 138
 139
 140 /**
 141  * Generate the depth /stencil test code.
 142  */
 143 static void
 144 generate_depth_stencil(LLVMBuilderRef builder,
 145                        const struct lp_fragment_shader_variant_key *key,
 146                        struct lp_type src_type,
 147                        struct lp_build_mask_context *mask,
 148                        LLVMValueRef stencil_refs[2],
 149                        LLVMValueRef src,
 150                        LLVMValueRef dst_ptr)
 151 {
 152    const struct util_format_description *format_desc;
 153    struct lp_type dst_type;
 154
 155    if (!key->depth.enabled && !key->stencil[0].enabled && !key->stencil[1].enabled)
 156       return;
 157
 158    format_desc = util_format_description(key->zsbuf_format);
 159    assert(format_desc);
 160
 161    /*
 162     * Depths are expected to be between 0 and 1, even if they are stored in
 163     * floats. Setting these bits here will ensure that the lp_build_conv() call
 164     * below won't try to unnecessarily clamp the incoming values.
 165     */
 166    if(src_type.floating) {
 167       src_type.sign = FALSE;
 168       src_type.norm = TRUE;
 169    }
 170    else {
 171       assert(!src_type.sign);
 172       assert(src_type.norm);
 173    }
 174
 175    /* Pick the depth type. */
 176    dst_type = lp_depth_type(format_desc, src_type.width*src_type.length);
 177
 178    /* FIXME: Cope with a depth test type with a different bit width. */
 179    assert(dst_type.width == src_type.width);
 180    assert(dst_type.length == src_type.length);
 181
 182    /* Convert fragment Z from float to integer */
 183    lp_build_conv(builder, src_type, dst_type, &src, 1, &src, 1);
 184
 185    dst_ptr = LLVMBuildBitCast(builder,
 186                               dst_ptr,
 187                               LLVMPointerType(lp_build_vec_type(dst_type), 0), "");
 188    lp_build_depth_stencil_test(builder,
 189                                &key->depth,
 190                                key->stencil,
 191                                dst_type,
 192                                format_desc,
 193                                mask,
 194                                stencil_refs,
 195                                src,
 196                                dst_ptr);
 197 }
 198
 199
 200 /**
 201  * Generate the code to do inside/outside triangle testing for the
 202  * four pixels in a 2x2 quad.  This will set the four elements of the
 203  * quad mask vector to 0 or ~0.
 204  * \param i  which quad of the quad group to test, in [0,3]
 205  */
 206 static void
 207 generate_tri_edge_mask(LLVMBuilderRef builder,
 208                        unsigned i,
 209                        LLVMValueRef *mask,      /* ivec4, out */
 210                        LLVMValueRef c0,         /* int32 */
 211                        LLVMValueRef c1,         /* int32 */
 212                        LLVMValueRef c2,         /* int32 */
 213                        LLVMValueRef step0_ptr,  /* ivec4 */
 214                        LLVMValueRef step1_ptr,  /* ivec4 */
 215                        LLVMValueRef step2_ptr)  /* ivec4 */
 216 {
 217 #define OPTIMIZE_IN_OUT_TEST 0
 218 #if OPTIMIZE_IN_OUT_TEST
 219    struct lp_build_if_state ifctx;
 220    LLVMValueRef not_draw_all;
 221 #endif
 222    struct lp_build_flow_context *flow;
 223    struct lp_type i32_type;
 224    LLVMTypeRef i32vec4_type, mask_type;
 225    LLVMValueRef c0_vec, c1_vec, c2_vec;
 226    LLVMValueRef in_out_mask;
 227
 228    assert(i < 4);
 229
 230    /* int32 vector type */
 231    memset(&i32_type, 0, sizeof i32_type);
 232    i32_type.floating = FALSE; /* values are integers */
 233    i32_type.sign = TRUE;      /* values are signed */
 234    i32_type.norm = FALSE;     /* values are not normalized */
 235    i32_type.width = 32;       /* 32-bit int values */
 236    i32_type.length = 4;       /* 4 elements per vector */
 237
 238    i32vec4_type = lp_build_int32_vec4_type();
 239
 240    mask_type = LLVMIntType(32 * 4);
 241
 242    /*
 243     * Use a conditional here to do detailed pixel in/out testing.
 244     * We only have to do this if c0 != INT_MIN.
 245     */
 246    flow = lp_build_flow_create(builder);
 247    lp_build_flow_scope_begin(flow);
 248
 249    {
 250 #if OPTIMIZE_IN_OUT_TEST
 251       /* not_draw_all = (c0 != INT_MIN) */
 252       not_draw_all = LLVMBuildICmp(builder,
 253                                    LLVMIntNE,
 254                                    c0,
 255                                    LLVMConstInt(LLVMInt32Type(), INT_MIN, 0),
 256                                    "");
 257
 258       in_out_mask = lp_build_const_int_vec(i32_type, ~0);
 259
 260
 261       lp_build_flow_scope_declare(flow, &in_out_mask);
 262
 263       /* if (not_draw_all) {... */
 264       lp_build_if(&ifctx, flow, builder, not_draw_all);
 265 #endif
 266       {
 267          LLVMValueRef step0_vec, step1_vec, step2_vec;
 268          LLVMValueRef m0_vec, m1_vec, m2_vec;
 269          LLVMValueRef index, m;
 270
 271          /* c0_vec = {c0, c0, c0, c0}
 272           * Note that we emit this code four times but LLVM optimizes away
 273           * three instances of it.
 274           */
 275          c0_vec = lp_build_broadcast(builder, i32vec4_type, c0);
 276          c1_vec = lp_build_broadcast(builder, i32vec4_type, c1);
 277          c2_vec = lp_build_broadcast(builder, i32vec4_type, c2);
 278          lp_build_name(c0_vec, "edgeconst0vec");
 279          lp_build_name(c1_vec, "edgeconst1vec");
 280          lp_build_name(c2_vec, "edgeconst2vec");
 281
 282          /* load step0vec, step1, step2 vec from memory */
 283          index = LLVMConstInt(LLVMInt32Type(), i, 0);
 284          step0_vec = LLVMBuildLoad(builder, LLVMBuildGEP(builder, step0_ptr, &index, 1, ""), "");
 285          step1_vec = LLVMBuildLoad(builder, LLVMBuildGEP(builder, step1_ptr, &index, 1, ""), "");
 286          step2_vec = LLVMBuildLoad(builder, LLVMBuildGEP(builder, step2_ptr, &index, 1, ""), "");
 287          lp_build_name(step0_vec, "step0vec");
 288          lp_build_name(step1_vec, "step1vec");
 289          lp_build_name(step2_vec, "step2vec");
 290
 291          /* m0_vec = step0_ptr[i] > c0_vec */
 292          m0_vec = lp_build_compare(builder, i32_type, PIPE_FUNC_GREATER, step0_vec, c0_vec);
 293          m1_vec = lp_build_compare(builder, i32_type, PIPE_FUNC_GREATER, step1_vec, c1_vec);
 294          m2_vec = lp_build_compare(builder, i32_type, PIPE_FUNC_GREATER, step2_vec, c2_vec);
 295
 296          /* in_out_mask = m0_vec & m1_vec & m2_vec */
 297          m = LLVMBuildAnd(builder, m0_vec, m1_vec, "");
 298          in_out_mask = LLVMBuildAnd(builder, m, m2_vec, "");
 299          lp_build_name(in_out_mask, "inoutmaskvec");
 300       }
 301 #if OPTIMIZE_IN_OUT_TEST
 302       lp_build_endif(&ifctx);
 303 #endif
 304
 305    }
 306    lp_build_flow_scope_end(flow);
 307    lp_build_flow_destroy(flow);
 308
 309    /* This is the initial alive/dead pixel mask for a quad of four pixels.
 310     * It's an int[4] vector with each word set to 0 or ~0.
 311     * Words will get cleared when pixels faile the Z test, etc.
 312     */
 313    *mask = in_out_mask;
 314 }
 315
 316
 317 static LLVMValueRef
 318 generate_scissor_test(LLVMBuilderRef builder,
 319                       LLVMValueRef context_ptr,
 320                       const struct lp_build_interp_soa_context *interp,
 321                       struct lp_type type)
 322 {
 323    LLVMTypeRef vec_type = lp_build_vec_type(type);
 324    LLVMValueRef xpos = interp->pos[0], ypos = interp->pos[1];
 325    LLVMValueRef xmin, ymin, xmax, ymax;
 326    LLVMValueRef m0, m1, m2, m3, m;
 327
 328    /* xpos, ypos contain the window coords for the four pixels in the quad */
 329    assert(xpos);
 330    assert(ypos);
 331
 332    /* get the current scissor bounds, convert to vectors */
 333    xmin = lp_jit_context_scissor_xmin_value(builder, context_ptr);
 334    xmin = lp_build_broadcast(builder, vec_type, xmin);
 335
 336    ymin = lp_jit_context_scissor_ymin_value(builder, context_ptr);
 337    ymin = lp_build_broadcast(builder, vec_type, ymin);
 338
 339    xmax = lp_jit_context_scissor_xmax_value(builder, context_ptr);
 340    xmax = lp_build_broadcast(builder, vec_type, xmax);
 341
 342    ymax = lp_jit_context_scissor_ymax_value(builder, context_ptr);
 343    ymax = lp_build_broadcast(builder, vec_type, ymax);
 344
 345    /* compare the fragment's position coordinates against the scissor bounds */
 346    m0 = lp_build_compare(builder, type, PIPE_FUNC_GEQUAL, xpos, xmin);
 347    m1 = lp_build_compare(builder, type, PIPE_FUNC_GEQUAL, ypos, ymin);
 348    m2 = lp_build_compare(builder, type, PIPE_FUNC_LESS, xpos, xmax);
 349    m3 = lp_build_compare(builder, type, PIPE_FUNC_LESS, ypos, ymax);
 350
 351    /* AND all the masks together */
 352    m = LLVMBuildAnd(builder, m0, m1, "");
 353    m = LLVMBuildAnd(builder, m, m2, "");
 354    m = LLVMBuildAnd(builder, m, m3, "");
 355
 356    lp_build_name(m, "scissormask");
 357
 358    return m;
 359 }
 360
 361
 362 static LLVMValueRef
 363 build_int32_vec_const(int value)
 364 {
 365    struct lp_type i32_type;
 366
 367    memset(&i32_type, 0, sizeof i32_type);
 368    i32_type.floating = FALSE; /* values are integers */
 369    i32_type.sign = TRUE;      /* values are signed */
 370    i32_type.norm = FALSE;     /* values are not normalized */
 371    i32_type.width = 32;       /* 32-bit int values */
 372    i32_type.length = 4;       /* 4 elements per vector */
 373    return lp_build_const_int_vec(i32_type, value);
 374 }
 375
 376
 377
 378 /**
 379  * Generate the fragment shader, depth/stencil test, and alpha tests.
 380  * \param i  which quad in the tile, in range [0,3]
 381  * \param do_tri_test  if 1, do triangle edge in/out testing
 382  */
 383 static void
 384 generate_fs(struct llvmpipe_context *lp,
 385             struct lp_fragment_shader *shader,
 386             const struct lp_fragment_shader_variant_key *key,
 387             LLVMBuilderRef builder,
 388             struct lp_type type,
 389             LLVMValueRef context_ptr,
 390             unsigned i,
 391             const struct lp_build_interp_soa_context *interp,
 392             struct lp_build_sampler_soa *sampler,
 393             LLVMValueRef *pmask,
 394             LLVMValueRef (*color)[4],
 395             LLVMValueRef depth_ptr,
 396             unsigned do_tri_test,
 397             LLVMValueRef c0,
 398             LLVMValueRef c1,
 399             LLVMValueRef c2,
 400             LLVMValueRef step0_ptr,
 401             LLVMValueRef step1_ptr,
 402             LLVMValueRef step2_ptr)
 403 {
 404    const struct tgsi_token *tokens = shader->base.tokens;
 405    LLVMTypeRef elem_type;
 406    LLVMTypeRef vec_type;
 407    LLVMTypeRef int_vec_type;
 408    LLVMValueRef consts_ptr;
 409    LLVMValueRef outputs[PIPE_MAX_SHADER_OUTPUTS][NUM_CHANNELS];
 410    LLVMValueRef z = interp->pos[2];
 411    LLVMValueRef stencil_refs[2];
 412    struct lp_build_flow_context *flow;
 413    struct lp_build_mask_context mask;
 414    boolean early_depth_stencil_test;
 415    unsigned attrib;
 416    unsigned chan;
 417    unsigned cbuf;
 418
 419    assert(i < 4);
 420
 421    stencil_refs[0] = lp_jit_context_stencil_ref_front_value(builder, context_ptr);
 422    stencil_refs[1] = lp_jit_context_stencil_ref_back_value(builder, context_ptr);
 423
 424    elem_type = lp_build_elem_type(type);
 425    vec_type = lp_build_vec_type(type);
 426    int_vec_type = lp_build_int_vec_type(type);
 427
 428    consts_ptr = lp_jit_context_constants(builder, context_ptr);
 429
 430    flow = lp_build_flow_create(builder);
 431
 432    memset(outputs, 0, sizeof outputs);
 433
 434    lp_build_flow_scope_begin(flow);
 435
 436    /* Declare the color and z variables */
 437    for(cbuf = 0; cbuf < key->nr_cbufs; cbuf++) {
 438       for(chan = 0; chan < NUM_CHANNELS; ++chan) {
 439          color[cbuf][chan] = LLVMGetUndef(vec_type);
 440          lp_build_flow_scope_declare(flow, &color[cbuf][chan]);
 441       }
 442    }
 443    lp_build_flow_scope_declare(flow, &z);
 444
 445    /* do triangle edge testing */
 446    if (do_tri_test) {
 447       generate_tri_edge_mask(builder, i, pmask,
 448                              c0, c1, c2, step0_ptr, step1_ptr, step2_ptr);
 449    }
 450    else {
 451       *pmask = build_int32_vec_const(~0);
 452    }
 453
 454    /* 'mask' will control execution based on quad's pixel alive/killed state */
 455    lp_build_mask_begin(&mask, flow, type, *pmask);
 456
 457    if (key->scissor) {
 458       LLVMValueRef smask =
 459          generate_scissor_test(builder, context_ptr, interp, type);
 460       lp_build_mask_update(&mask, smask);
 461    }
 462
 463    early_depth_stencil_test =
 464       (key->depth.enabled || key->stencil[0].enabled) &&
 465       !key->alpha.enabled &&
 466       !shader->info.uses_kill &&
 467       !shader->info.writes_z;
 468
 469    if (early_depth_stencil_test)
 470       generate_depth_stencil(builder, key,
 471                              type, &mask,
 472                              stencil_refs, z, depth_ptr);
 473
 474    lp_build_tgsi_soa(builder, tokens, type, &mask,
 475                      consts_ptr, interp->pos, interp->inputs,
 476                      outputs, sampler);
 477
 478    for (attrib = 0; attrib < shader->info.num_outputs; ++attrib) {
 479       for(chan = 0; chan < NUM_CHANNELS; ++chan) {
 480          if(outputs[attrib][chan]) {
 481             LLVMValueRef out = LLVMBuildLoad(builder, outputs[attrib][chan], "");
 482             lp_build_name(out, "output%u.%u.%c", i, attrib, "xyzw"[chan]);
 483
 484             switch (shader->info.output_semantic_name[attrib]) {
 485             case TGSI_SEMANTIC_COLOR:
 486                {
 487                   unsigned cbuf = shader->info.output_semantic_index[attrib];
 488
 489                   lp_build_name(out, "color%u.%u.%c", i, attrib, "rgba"[chan]);
 490
 491                   /* Alpha test */
 492                   /* XXX: should the alpha reference value be passed separately? */
 493                   /* XXX: should only test the final assignment to alpha */
 494                   if(cbuf == 0 && chan == 3) {
 495                      LLVMValueRef alpha = out;
 496                      LLVMValueRef alpha_ref_value;
 497                      alpha_ref_value = lp_jit_context_alpha_ref_value(builder, context_ptr);
 498                      alpha_ref_value = lp_build_broadcast(builder, vec_type, alpha_ref_value);
 499                      lp_build_alpha_test(builder, &key->alpha, type,
 500                                          &mask, alpha, alpha_ref_value);
 501                   }
 502
 503                   color[cbuf][chan] = out;
 504                   break;
 505                }
 506
 507             case TGSI_SEMANTIC_POSITION:
 508                if(chan == 2)
 509                   z = out;
 510                break;
 511             }
 512          }
 513       }
 514    }
 515
 516    if (!early_depth_stencil_test)
 517       generate_depth_stencil(builder, key,
 518                              type, &mask,
 519                              stencil_refs, z, depth_ptr);
 520
 521    lp_build_mask_end(&mask);
 522
 523    lp_build_flow_scope_end(flow);
 524
 525    lp_build_flow_destroy(flow);
 526
 527    *pmask = mask.value;
 528
 529 }
 530
 531
 532 /**
 533  * Generate color blending and color output.
 534  */
 535 static void
 536 generate_blend(const struct pipe_blend_state *blend,
 537                LLVMBuilderRef builder,
 538                struct lp_type type,
 539                LLVMValueRef context_ptr,
 540                LLVMValueRef mask,
 541                LLVMValueRef *src,
 542                LLVMValueRef dst_ptr)
 543 {
 544    struct lp_build_context bld;
 545    struct lp_build_flow_context *flow;
 546    struct lp_build_mask_context mask_ctx;
 547    LLVMTypeRef vec_type;
 548    LLVMTypeRef int_vec_type;
 549    LLVMValueRef const_ptr;
 550    LLVMValueRef con[4];
 551    LLVMValueRef dst[4];
 552    LLVMValueRef res[4];
 553    unsigned chan;
 554
 555    lp_build_context_init(&bld, builder, type);
 556
 557    flow = lp_build_flow_create(builder);
 558
 559    /* we'll use this mask context to skip blending if all pixels are dead */
 560    lp_build_mask_begin(&mask_ctx, flow, type, mask);
 561
 562    vec_type = lp_build_vec_type(type);
 563    int_vec_type = lp_build_int_vec_type(type);
 564
 565    const_ptr = lp_jit_context_blend_color(builder, context_ptr);
 566    const_ptr = LLVMBuildBitCast(builder, const_ptr,
 567                                 LLVMPointerType(vec_type, 0), "");
 568
 569    for(chan = 0; chan < 4; ++chan) {
 570       LLVMValueRef index = LLVMConstInt(LLVMInt32Type(), chan, 0);
 571       con[chan] = LLVMBuildLoad(builder, LLVMBuildGEP(builder, const_ptr, &index, 1, ""), "");
 572
 573       dst[chan] = LLVMBuildLoad(builder, LLVMBuildGEP(builder, dst_ptr, &index, 1, ""), "");
 574
 575       lp_build_name(con[chan], "con.%c", "rgba"[chan]);
 576       lp_build_name(dst[chan], "dst.%c", "rgba"[chan]);
 577    }
 578
 579    lp_build_blend_soa(builder, blend, type, src, dst, con, res);
 580
 581    for(chan = 0; chan < 4; ++chan) {
 582       if(blend->rt[0].colormask & (1 << chan)) {
 583          LLVMValueRef index = LLVMConstInt(LLVMInt32Type(), chan, 0);
 584          lp_build_name(res[chan], "res.%c", "rgba"[chan]);
 585          res[chan] = lp_build_select(&bld, mask, res[chan], dst[chan]);
 586          LLVMBuildStore(builder, res[chan], LLVMBuildGEP(builder, dst_ptr, &index, 1, ""));
 587       }
 588    }
 589
 590    lp_build_mask_end(&mask_ctx);
 591    lp_build_flow_destroy(flow);
 592 }
 593
 594
 595 /** casting function to avoid compiler warnings */
 596 static lp_jit_frag_func
 597 cast_voidptr_to_lp_jit_frag_func(void *p)
 598 {
 599    union {
 600       void *v;
 601       lp_jit_frag_func f;
 602    } tmp;
 603    assert(sizeof(tmp.v) == sizeof(tmp.f));
 604    tmp.v = p;
 605    return tmp.f;
 606 }
 607
 608
 609 /**
 610  * Generate the runtime callable function for the whole fragment pipeline.
 611  * Note that the function which we generate operates on a block of 16
 612  * pixels at at time.  The block contains 2x2 quads.  Each quad contains
 613  * 2x2 pixels.
 614  */
 615 static void
 616 generate_fragment(struct llvmpipe_context *lp,
 617                   struct lp_fragment_shader *shader,
 618                   struct lp_fragment_shader_variant *variant,
 619                   unsigned do_tri_test)
 620 {
 621    struct llvmpipe_screen *screen = llvmpipe_screen(lp->pipe.screen);
 622    const struct lp_fragment_shader_variant_key *key = &variant->key;
 623    struct lp_type fs_type;
 624    struct lp_type blend_type;
 625    LLVMTypeRef fs_elem_type;
 626    LLVMTypeRef fs_vec_type;
 627    LLVMTypeRef fs_int_vec_type;
 628    LLVMTypeRef blend_vec_type;
 629    LLVMTypeRef blend_int_vec_type;
 630    LLVMTypeRef arg_types[14];
 631    LLVMTypeRef func_type;
 632    LLVMTypeRef int32_vec4_type = lp_build_int32_vec4_type();
 633    LLVMValueRef context_ptr;
 634    LLVMValueRef x;
 635    LLVMValueRef y;
 636    LLVMValueRef a0_ptr;
 637    LLVMValueRef dadx_ptr;
 638    LLVMValueRef dady_ptr;
 639    LLVMValueRef color_ptr_ptr;
 640    LLVMValueRef depth_ptr;
 641    LLVMValueRef c0, c1, c2, step0_ptr, step1_ptr, step2_ptr;
 642    LLVMBasicBlockRef block;
 643    LLVMBuilderRef builder;
 644    LLVMValueRef x0;
 645    LLVMValueRef y0;
 646    struct lp_build_sampler_soa *sampler;
 647    struct lp_build_interp_soa_context interp;
 648    LLVMValueRef fs_mask[LP_MAX_VECTOR_LENGTH];
 649    LLVMValueRef fs_out_color[PIPE_MAX_COLOR_BUFS][NUM_CHANNELS][LP_MAX_VECTOR_LENGTH];
 650    LLVMValueRef blend_mask;
 651    LLVMValueRef blend_in_color[NUM_CHANNELS];
 652    LLVMValueRef function;
 653    unsigned num_fs;
 654    unsigned i;
 655    unsigned chan;
 656    unsigned cbuf;
 657
 658
 659    /* TODO: actually pick these based on the fs and color buffer
 660     * characteristics. */
 661
 662    memset(&fs_type, 0, sizeof fs_type);
 663    fs_type.floating = TRUE; /* floating point values */
 664    fs_type.sign = TRUE;     /* values are signed */
 665    fs_type.norm = FALSE;    /* values are not limited to [0,1] or [-1,1] */
 666    fs_type.width = 32;      /* 32-bit float */
 667    fs_type.length = 4;      /* 4 elements per vector */
 668    num_fs = 4;              /* number of quads per block */
 669
 670    memset(&blend_type, 0, sizeof blend_type);
 671    blend_type.floating = FALSE; /* values are integers */
 672    blend_type.sign = FALSE;     /* values are unsigned */
 673    blend_type.norm = TRUE;      /* values are in [0,1] or [-1,1] */
 674    blend_type.width = 8;        /* 8-bit ubyte values */
 675    blend_type.length = 16;      /* 16 elements per vector */
 676
 677    /*
 678     * Generate the function prototype. Any change here must be reflected in
 679     * lp_jit.h's lp_jit_frag_func function pointer type, and vice-versa.
 680     */
 681
 682    fs_elem_type = lp_build_elem_type(fs_type);
 683    fs_vec_type = lp_build_vec_type(fs_type);
 684    fs_int_vec_type = lp_build_int_vec_type(fs_type);
 685
 686    blend_vec_type = lp_build_vec_type(blend_type);
 687    blend_int_vec_type = lp_build_int_vec_type(blend_type);
 688
 689    arg_types[0] = screen->context_ptr_type;            /* context */
 690    arg_types[1] = LLVMInt32Type();                     /* x */
 691    arg_types[2] = LLVMInt32Type();                     /* y */
 692    arg_types[3] = LLVMPointerType(fs_elem_type, 0);    /* a0 */
 693    arg_types[4] = LLVMPointerType(fs_elem_type, 0);    /* dadx */
 694    arg_types[5] = LLVMPointerType(fs_elem_type, 0);    /* dady */
 695    arg_types[6] = LLVMPointerType(LLVMPointerType(blend_vec_type, 0), 0);  /* color */
 696    arg_types[7] = LLVMPointerType(fs_int_vec_type, 0); /* depth */
 697    arg_types[8] = LLVMInt32Type();                     /* c0 */
 698    arg_types[9] = LLVMInt32Type();                     /* c1 */
 699    arg_types[10] = LLVMInt32Type();                    /* c2 */
 700    /* Note: the step arrays are built as int32[16] but we interpret
 701     * them here as int32_vec4[4].
 702     */
 703    arg_types[11] = LLVMPointerType(int32_vec4_type, 0);/* step0 */
 704    arg_types[12] = LLVMPointerType(int32_vec4_type, 0);/* step1 */
 705    arg_types[13] = LLVMPointerType(int32_vec4_type, 0);/* step2 */
 706
 707    func_type = LLVMFunctionType(LLVMVoidType(), arg_types, Elements(arg_types), 0);
 708
 709    function = LLVMAddFunction(screen->module, "shader", func_type);
 710    LLVMSetFunctionCallConv(function, LLVMCCallConv);
 711
 712    variant->function[do_tri_test] = function;
 713
 714
 715    /* XXX: need to propagate noalias down into color param now we are
 716     * passing a pointer-to-pointer?
 717     */
 718    for(i = 0; i < Elements(arg_types); ++i)
 719       if(LLVMGetTypeKind(arg_types[i]) == LLVMPointerTypeKind)
 720          LLVMAddAttribute(LLVMGetParam(function, i), LLVMNoAliasAttribute);
 721
 722    context_ptr  = LLVMGetParam(function, 0);
 723    x            = LLVMGetParam(function, 1);
 724    y            = LLVMGetParam(function, 2);
 725    a0_ptr       = LLVMGetParam(function, 3);
 726    dadx_ptr     = LLVMGetParam(function, 4);
 727    dady_ptr     = LLVMGetParam(function, 5);
 728    color_ptr_ptr = LLVMGetParam(function, 6);
 729    depth_ptr    = LLVMGetParam(function, 7);
 730    c0           = LLVMGetParam(function, 8);
 731    c1           = LLVMGetParam(function, 9);
 732    c2           = LLVMGetParam(function, 10);
 733    step0_ptr    = LLVMGetParam(function, 11);
 734    step1_ptr    = LLVMGetParam(function, 12);
 735    step2_ptr    = LLVMGetParam(function, 13);
 736
 737    lp_build_name(context_ptr, "context");
 738    lp_build_name(x, "x");
 739    lp_build_name(y, "y");
 740    lp_build_name(a0_ptr, "a0");
 741    lp_build_name(dadx_ptr, "dadx");
 742    lp_build_name(dady_ptr, "dady");
 743    lp_build_name(color_ptr_ptr, "color_ptr");
 744    lp_build_name(depth_ptr, "depth");
 745    lp_build_name(c0, "c0");
 746    lp_build_name(c1, "c1");
 747    lp_build_name(c2, "c2");
 748    lp_build_name(step0_ptr, "step0");
 749    lp_build_name(step1_ptr, "step1");
 750    lp_build_name(step2_ptr, "step2");
 751
 752    /*
 753     * Function body
 754     */
 755
 756    block = LLVMAppendBasicBlock(function, "entry");
 757    builder = LLVMCreateBuilder();
 758    LLVMPositionBuilderAtEnd(builder, block);
 759
 760    generate_pos0(builder, x, y, &x0, &y0);
 761
 762    lp_build_interp_soa_init(&interp,
 763                             shader->base.tokens,
 764                             key->flatshade,
 765                             builder, fs_type,
 766                             a0_ptr, dadx_ptr, dady_ptr,
 767                             x0, y0);
 768
 769    /* code generated texture sampling */
 770    sampler = lp_llvm_sampler_soa_create(key->sampler, context_ptr);
 771
 772    /* loop over quads in the block */
 773    for(i = 0; i < num_fs; ++i) {
 774       LLVMValueRef index = LLVMConstInt(LLVMInt32Type(), i, 0);
 775       LLVMValueRef out_color[PIPE_MAX_COLOR_BUFS][NUM_CHANNELS];
 776       LLVMValueRef depth_ptr_i;
 777       int cbuf;
 778
 779       if(i != 0)
 780          lp_build_interp_soa_update(&interp, i);
 781
 782       depth_ptr_i = LLVMBuildGEP(builder, depth_ptr, &index, 1, "");
 783
 784       generate_fs(lp, shader, key,
 785                   builder,
 786                   fs_type,
 787                   context_ptr,
 788                   i,
 789                   &interp,
 790                   sampler,
 791                   &fs_mask[i], /* output */
 792                   out_color,
 793                   depth_ptr_i,
 794                   do_tri_test,
 795                   c0, c1, c2,
 796                   step0_ptr, step1_ptr, step2_ptr);
 797
 798       for(cbuf = 0; cbuf < key->nr_cbufs; cbuf++)
 799          for(chan = 0; chan < NUM_CHANNELS; ++chan)
 800             fs_out_color[cbuf][chan][i] = out_color[cbuf][chan];
 801    }
 802
 803    sampler->destroy(sampler);
 804
 805    /* Loop over color outputs / color buffers to do blending.
 806     */
 807    for(cbuf = 0; cbuf < key->nr_cbufs; cbuf++) {
 808       LLVMValueRef color_ptr;
 809       LLVMValueRef index = LLVMConstInt(LLVMInt32Type(), cbuf, 0);
 810
 811       /*
 812        * Convert the fs's output color and mask to fit to the blending type.
 813        */
 814       for(chan = 0; chan < NUM_CHANNELS; ++chan) {
 815          lp_build_conv(builder, fs_type, blend_type,
 816                        fs_out_color[cbuf][chan], num_fs,
 817                        &blend_in_color[chan], 1);
 818          lp_build_name(blend_in_color[chan], "color%d.%c", cbuf, "rgba"[chan]);
 819       }
 820
 821       lp_build_conv_mask(builder, fs_type, blend_type,
 822                          fs_mask, num_fs,
 823                          &blend_mask, 1);
 824
 825       color_ptr = LLVMBuildLoad(builder,
 826                                 LLVMBuildGEP(builder, color_ptr_ptr, &index, 1, ""),
 827                                 "");
 828       lp_build_name(color_ptr, "color_ptr%d", cbuf);
 829
 830       /*
 831        * Blending.
 832        */
 833       generate_blend(&key->blend,
 834                      builder,
 835                      blend_type,
 836                      context_ptr,
 837                      blend_mask,
 838                      blend_in_color,
 839                      color_ptr);
 840    }
 841
 842    LLVMBuildRetVoid(builder);
 843
 844    LLVMDisposeBuilder(builder);
 845
 846
 847    /* Verify the LLVM IR.  If invalid, dump and abort */
 848 #ifdef DEBUG
 849    if(LLVMVerifyFunction(function, LLVMPrintMessageAction)) {
 850       if (1)
 851          LLVMDumpValue(function);
 852       abort();
 853    }
 854 #endif
 855
 856    /* Apply optimizations to LLVM IR */
 857    if (1)
 858       LLVMRunFunctionPassManager(screen->pass, function);
 859
 860    if (LP_DEBUG & DEBUG_JIT) {
 861       /* Print the LLVM IR to stderr */
 862       LLVMDumpValue(function);
 863       debug_printf("\n");
 864    }
 865
 866    /*
 867     * Translate the LLVM IR into machine code.
 868     */
 869    {
 870       void *f = LLVMGetPointerToGlobal(screen->engine, function);
 871
 872       variant->jit_function[do_tri_test] = cast_voidptr_to_lp_jit_frag_func(f);
 873
 874       if (LP_DEBUG & DEBUG_ASM)
 875          lp_disassemble(f);
 876    }
 877 }
 878
 879
 880 static struct lp_fragment_shader_variant *
 881 generate_variant(struct llvmpipe_context *lp,
 882                  struct lp_fragment_shader *shader,
 883                  const struct lp_fragment_shader_variant_key *key)
 884 {
 885    struct lp_fragment_shader_variant *variant;
 886
 887    if (LP_DEBUG & DEBUG_JIT) {
 888       unsigned i;
 889
 890       tgsi_dump(shader->base.tokens, 0);
 891       if(key->depth.enabled) {
 892          debug_printf("depth.format = %s\n", util_format_name(key->zsbuf_format));
 893          debug_printf("depth.func = %s\n", util_dump_func(key->depth.func, TRUE));
 894          debug_printf("depth.writemask = %u\n", key->depth.writemask);
 895       }
 896       if(key->alpha.enabled) {
 897          debug_printf("alpha.func = %s\n", util_dump_func(key->alpha.func, TRUE));
 898          debug_printf("alpha.ref_value = %f\n", key->alpha.ref_value);
 899       }
 900       if(key->blend.logicop_enable) {
 901          debug_printf("blend.logicop_func = %u\n", key->blend.logicop_func);
 902       }
 903       else if(key->blend.rt[0].blend_enable) {
 904          debug_printf("blend.rgb_func = %s\n",   util_dump_blend_func  (key->blend.rt[0].rgb_func, TRUE));
 905          debug_printf("rgb_src_factor = %s\n",   util_dump_blend_factor(key->blend.rt[0].rgb_src_factor, TRUE));
 906          debug_printf("rgb_dst_factor = %s\n",   util_dump_blend_factor(key->blend.rt[0].rgb_dst_factor, TRUE));
 907          debug_printf("alpha_func = %s\n",       util_dump_blend_func  (key->blend.rt[0].alpha_func, TRUE));
 908          debug_printf("alpha_src_factor = %s\n", util_dump_blend_factor(key->blend.rt[0].alpha_src_factor, TRUE));
 909          debug_printf("alpha_dst_factor = %s\n", util_dump_blend_factor(key->blend.rt[0].alpha_dst_factor, TRUE));
 910       }
 911       debug_printf("blend.colormask = 0x%x\n", key->blend.rt[0].colormask);
 912       for(i = 0; i < PIPE_MAX_SAMPLERS; ++i) {
 913          if(key->sampler[i].format) {
 914             debug_printf("sampler[%u] = \n", i);
 915             debug_printf("  .format = %s\n",
 916                          util_format_name(key->sampler[i].format));
 917             debug_printf("  .target = %s\n",
 918                          util_dump_tex_target(key->sampler[i].target, TRUE));
 919             debug_printf("  .pot = %u %u %u\n",
 920                          key->sampler[i].pot_width,
 921                          key->sampler[i].pot_height,
 922                          key->sampler[i].pot_depth);
 923             debug_printf("  .wrap = %s %s %s\n",
 924                          util_dump_tex_wrap(key->sampler[i].wrap_s, TRUE),
 925                          util_dump_tex_wrap(key->sampler[i].wrap_t, TRUE),
 926                          util_dump_tex_wrap(key->sampler[i].wrap_r, TRUE));
 927             debug_printf("  .min_img_filter = %s\n",
 928                          util_dump_tex_filter(key->sampler[i].min_img_filter, TRUE));
 929             debug_printf("  .min_mip_filter = %s\n",
 930                          util_dump_tex_mipfilter(key->sampler[i].min_mip_filter, TRUE));
 931             debug_printf("  .mag_img_filter = %s\n",
 932                          util_dump_tex_filter(key->sampler[i].mag_img_filter, TRUE));
 933             if(key->sampler[i].compare_mode != PIPE_TEX_COMPARE_NONE)
 934                debug_printf("  .compare_func = %s\n", util_dump_func(key->sampler[i].compare_func, TRUE));
 935             debug_printf("  .normalized_coords = %u\n", key->sampler[i].normalized_coords);
 936          }
 937       }
 938    }
 939
 940    variant = CALLOC_STRUCT(lp_fragment_shader_variant);
 941    if(!variant)
 942       return NULL;
 943
 944    variant->shader = shader;
 945    memcpy(&variant->key, key, sizeof *key);
 946
 947    generate_fragment(lp, shader, variant, 0);
 948    generate_fragment(lp, shader, variant, 1);
 949
 950    /* insert new variant into linked list */
 951    variant->next = shader->variants;
 952    shader->variants = variant;
 953
 954    return variant;
 955 }
 956
 957
 958 void *
 959 llvmpipe_create_fs_state(struct pipe_context *pipe,
 960                          const struct pipe_shader_state *templ)
 961 {
 962    struct lp_fragment_shader *shader;
 963
 964    shader = CALLOC_STRUCT(lp_fragment_shader);
 965    if (!shader)
 966       return NULL;
 967
 968    /* get/save the summary info for this shader */
 969    tgsi_scan_shader(templ->tokens, &shader->info);
 970
 971    /* we need to keep a local copy of the tokens */
 972    shader->base.tokens = tgsi_dup_tokens(templ->tokens);
 973
 974    return shader;
 975 }
 976
 977
 978 void
 979 llvmpipe_bind_fs_state(struct pipe_context *pipe, void *fs)
 980 {
 981    struct llvmpipe_context *llvmpipe = llvmpipe_context(pipe);
 982
 983    if (llvmpipe->fs == fs)
 984       return;
 985
 986    draw_flush(llvmpipe->draw);
 987
 988    llvmpipe->fs = fs;
 989
 990    llvmpipe->dirty |= LP_NEW_FS;
 991 }
 992
 993
 994 void
 995 llvmpipe_delete_fs_state(struct pipe_context *pipe, void *fs)
 996 {
 997    struct llvmpipe_context *llvmpipe = llvmpipe_context(pipe);
 998    struct llvmpipe_screen *screen = llvmpipe_screen(pipe->screen);
 999    struct lp_fragment_shader *shader = fs;
1000    struct lp_fragment_shader_variant *variant;
1001
1002    assert(fs != llvmpipe->fs);
1003    (void) llvmpipe;
1004
1005    /*
1006     * XXX: we need to flush the context until we have some sort of reference
1007     * counting in fragment shaders as they may still be binned
1008     */
1009    draw_flush(llvmpipe->draw);
1010    lp_setup_flush(llvmpipe->setup, 0);
1011
1012    variant = shader->variants;
1013    while(variant) {
1014       struct lp_fragment_shader_variant *next = variant->next;
1015       unsigned i;
1016
1017       for (i = 0; i < Elements(variant->function); i++) {
1018          if (variant->function[i]) {
1019             if (variant->jit_function[i])
1020                LLVMFreeMachineCodeForFunction(screen->engine,
1021                                               variant->function[i]);
1022             LLVMDeleteFunction(variant->function[i]);
1023          }
1024       }
1025
1026       FREE(variant);
1027
1028       variant = next;
1029    }
1030
1031    FREE((void *) shader->base.tokens);
1032    FREE(shader);
1033 }
1034
1035
1036
1037 void
1038 llvmpipe_set_constant_buffer(struct pipe_context *pipe,
1039                              uint shader, uint index,
1040                              struct pipe_buffer *constants)
1041 {
1042    struct llvmpipe_context *llvmpipe = llvmpipe_context(pipe);
1043    unsigned size = constants ? constants->size : 0;
1044    const void *data = constants ? llvmpipe_buffer(constants)->data : NULL;
1045
1046    assert(shader < PIPE_SHADER_TYPES);
1047    assert(index == 0);
1048
1049    if(llvmpipe->constants[shader] == constants)
1050       return;
1051
1052    draw_flush(llvmpipe->draw);
1053
1054    /* note: reference counting */
1055    pipe_buffer_reference(&llvmpipe->constants[shader], constants);
1056
1057    if(shader == PIPE_SHADER_VERTEX) {
1058       draw_set_mapped_constant_buffer(llvmpipe->draw, PIPE_SHADER_VERTEX, 0,
1059                                       data, size);
1060    }
1061
1062    llvmpipe->dirty |= LP_NEW_CONSTANTS;
1063 }
1064
1065
1066 /**
1067  * We need to generate several variants of the fragment pipeline to match
1068  * all the combinations of the contributing state atoms.
1069  *
1070  * TODO: there is actually no reason to tie this to context state -- the
1071  * generated code could be cached globally in the screen.
1072  */
1073 static void
1074 make_variant_key(struct llvmpipe_context *lp,
1075                  struct lp_fragment_shader *shader,
1076                  struct lp_fragment_shader_variant_key *key)
1077 {
1078    unsigned i;
1079
1080    memset(key, 0, sizeof *key);
1081
1082    if (lp->framebuffer.zsbuf) {
1083       if (lp->depth_stencil->depth.enabled) {
1084          key->zsbuf_format = lp->framebuffer.zsbuf->format;
1085          memcpy(&key->depth, &lp->depth_stencil->depth, sizeof key->depth);
1086       }
1087       if (lp->depth_stencil->stencil[0].enabled) {
1088          key->zsbuf_format = lp->framebuffer.zsbuf->format;
1089          memcpy(&key->stencil, &lp->depth_stencil->stencil, sizeof key->stencil);
1090       }
1091    }
1092
1093    key->alpha.enabled = lp->depth_stencil->alpha.enabled;
1094    if(key->alpha.enabled)
1095       key->alpha.func = lp->depth_stencil->alpha.func;
1096    /* alpha.ref_value is passed in jit_context */
1097
1098    key->flatshade = lp->rasterizer->flatshade;
1099    key->scissor = lp->rasterizer->scissor;
1100
1101    if (lp->framebuffer.nr_cbufs) {
1102       memcpy(&key->blend, lp->blend, sizeof key->blend);
1103    }
1104
1105    key->nr_cbufs = lp->framebuffer.nr_cbufs;
1106    for (i = 0; i < lp->framebuffer.nr_cbufs; i++) {
1107       const struct util_format_description *format_desc;
1108       unsigned chan;
1109
1110       format_desc = util_format_description(lp->framebuffer.cbufs[i]->format);
1111       assert(format_desc->layout == UTIL_FORMAT_COLORSPACE_RGB ||
1112              format_desc->layout == UTIL_FORMAT_COLORSPACE_SRGB);
1113
1114       /* mask out color channels not present in the color buffer.
1115        * Should be simple to incorporate per-cbuf writemasks:
1116        */
1117       for(chan = 0; chan < 4; ++chan) {
1118          enum util_format_swizzle swizzle = format_desc->swizzle[chan];
1119
1120          if(swizzle <= UTIL_FORMAT_SWIZZLE_W)
1121             key->blend.rt[0].colormask |= (1 << chan);
1122       }
1123    }
1124
1125    for(i = 0; i < PIPE_MAX_SAMPLERS; ++i)
1126       if(shader->info.file_mask[TGSI_FILE_SAMPLER] & (1 << i))
1127          lp_sampler_static_state(&key->sampler[i], lp->fragment_sampler_views[i]->texture, lp->sampler[i]);
1128 }
1129
1130
1131 /**
1132  * Update fragment state.  This is called just prior to drawing
1133  * something when some fragment-related state has changed.
1134  */
1135 void
1136 llvmpipe_update_fs(struct llvmpipe_context *lp)
1137 {
1138    struct lp_fragment_shader *shader = lp->fs;
1139    struct lp_fragment_shader_variant_key key;
1140    struct lp_fragment_shader_variant *variant;
1141    boolean opaque;
1142
1143    make_variant_key(lp, shader, &key);
1144
1145    variant = shader->variants;
1146    while(variant) {
1147       if(memcmp(&variant->key, &key, sizeof key) == 0)
1148          break;
1149
1150       variant = variant->next;
1151    }
1152
1153    if (!variant) {
1154       int64_t t0, t1;
1155       int64_t dt;
1156       t0 = os_time_get();
1157
1158       variant = generate_variant(lp, shader, &key);
1159
1160       t1 = os_time_get();
1161       dt = t1 - t0;
1162       LP_COUNT_ADD(llvm_compile_time, dt);
1163       LP_COUNT_ADD(nr_llvm_compiles, 2);  /* emit vs. omit in/out test */
1164    }
1165
1166    shader->current = variant;
1167
1168    /* TODO: put this in the variant */
1169    /* TODO: most of these can be relaxed, in particular the colormask */
1170    opaque = !key.blend.logicop_enable &&
1171             !key.blend.rt[0].blend_enable &&
1172             key.blend.rt[0].colormask == 0xf &&
1173             !key.stencil[0].enabled &&
1174             !key.alpha.enabled &&
1175             !key.depth.enabled &&
1176             !key.scissor &&
1177             !shader->info.uses_kill
1178             ? TRUE : FALSE;
1179
1180    lp_setup_set_fs_functions(lp->setup,
1181                              shader->current->jit_function[0],
1182                              shader->current->jit_function[1],
1183                              opaque);
1184 }