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,
 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;
 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 = lp_jit_context_stencil_ref_values(builder, context_ptr);
 422
 423    elem_type = lp_build_elem_type(type);
 424    vec_type = lp_build_vec_type(type);
 425    int_vec_type = lp_build_int_vec_type(type);
 426
 427    consts_ptr = lp_jit_context_constants(builder, context_ptr);
 428
 429    flow = lp_build_flow_create(builder);
 430
 431    memset(outputs, 0, sizeof outputs);
 432
 433    lp_build_flow_scope_begin(flow);
 434
 435    /* Declare the color and z variables */
 436    for(cbuf = 0; cbuf < key->nr_cbufs; cbuf++) {
 437       for(chan = 0; chan < NUM_CHANNELS; ++chan) {
 438          color[cbuf][chan] = LLVMGetUndef(vec_type);
 439          lp_build_flow_scope_declare(flow, &color[cbuf][chan]);
 440       }
 441    }
 442    lp_build_flow_scope_declare(flow, &z);
 443
 444    /* do triangle edge testing */
 445    if (do_tri_test) {
 446       generate_tri_edge_mask(builder, i, pmask,
 447                              c0, c1, c2, step0_ptr, step1_ptr, step2_ptr);
 448    }
 449    else {
 450       *pmask = build_int32_vec_const(~0);
 451    }
 452
 453    /* 'mask' will control execution based on quad's pixel alive/killed state */
 454    lp_build_mask_begin(&mask, flow, type, *pmask);
 455
 456    if (key->scissor) {
 457       LLVMValueRef smask =
 458          generate_scissor_test(builder, context_ptr, interp, type);
 459       lp_build_mask_update(&mask, smask);
 460    }
 461
 462    early_depth_stencil_test =
 463       (key->depth.enabled || key->stencil[0].enabled) &&
 464       !key->alpha.enabled &&
 465       !shader->info.uses_kill &&
 466       !shader->info.writes_z;
 467
 468    if (early_depth_stencil_test)
 469       generate_depth_stencil(builder, key,
 470                              type, &mask,
 471                              stencil_refs, z, depth_ptr);
 472
 473    lp_build_tgsi_soa(builder, tokens, type, &mask,
 474                      consts_ptr, interp->pos, interp->inputs,
 475                      outputs, sampler);
 476
 477    for (attrib = 0; attrib < shader->info.num_outputs; ++attrib) {
 478       for(chan = 0; chan < NUM_CHANNELS; ++chan) {
 479          if(outputs[attrib][chan]) {
 480             LLVMValueRef out = LLVMBuildLoad(builder, outputs[attrib][chan], "");
 481             lp_build_name(out, "output%u.%u.%c", i, attrib, "xyzw"[chan]);
 482
 483             switch (shader->info.output_semantic_name[attrib]) {
 484             case TGSI_SEMANTIC_COLOR:
 485                {
 486                   unsigned cbuf = shader->info.output_semantic_index[attrib];
 487
 488                   lp_build_name(out, "color%u.%u.%c", i, attrib, "rgba"[chan]);
 489
 490                   /* Alpha test */
 491                   /* XXX: should the alpha reference value be passed separately? */
 492                   /* XXX: should only test the final assignment to alpha */
 493                   if(cbuf == 0 && chan == 3) {
 494                      LLVMValueRef alpha = out;
 495                      LLVMValueRef alpha_ref_value;
 496                      alpha_ref_value = lp_jit_context_alpha_ref_value(builder, context_ptr);
 497                      alpha_ref_value = lp_build_broadcast(builder, vec_type, alpha_ref_value);
 498                      lp_build_alpha_test(builder, &key->alpha, type,
 499                                          &mask, alpha, alpha_ref_value);
 500                   }
 501
 502                   color[cbuf][chan] = out;
 503                   break;
 504                }
 505
 506             case TGSI_SEMANTIC_POSITION:
 507                if(chan == 2)
 508                   z = out;
 509                break;
 510             }
 511          }
 512       }
 513    }
 514
 515    if (!early_depth_stencil_test)
 516       generate_depth_stencil(builder, key,
 517                              type, &mask,
 518                              stencil_refs, z, depth_ptr);
 519
 520    lp_build_mask_end(&mask);
 521
 522    lp_build_flow_scope_end(flow);
 523
 524    lp_build_flow_destroy(flow);
 525
 526    *pmask = mask.value;
 527
 528 }
 529
 530
 531 /**
 532  * Generate color blending and color output.
 533  */
 534 static void
 535 generate_blend(const struct pipe_blend_state *blend,
 536                LLVMBuilderRef builder,
 537                struct lp_type type,
 538                LLVMValueRef context_ptr,
 539                LLVMValueRef mask,
 540                LLVMValueRef *src,
 541                LLVMValueRef dst_ptr)
 542 {
 543    struct lp_build_context bld;
 544    struct lp_build_flow_context *flow;
 545    struct lp_build_mask_context mask_ctx;
 546    LLVMTypeRef vec_type;
 547    LLVMTypeRef int_vec_type;
 548    LLVMValueRef const_ptr;
 549    LLVMValueRef con[4];
 550    LLVMValueRef dst[4];
 551    LLVMValueRef res[4];
 552    unsigned chan;
 553
 554    lp_build_context_init(&bld, builder, type);
 555
 556    flow = lp_build_flow_create(builder);
 557
 558    /* we'll use this mask context to skip blending if all pixels are dead */
 559    lp_build_mask_begin(&mask_ctx, flow, type, mask);
 560
 561    vec_type = lp_build_vec_type(type);
 562    int_vec_type = lp_build_int_vec_type(type);
 563
 564    const_ptr = lp_jit_context_blend_color(builder, context_ptr);
 565    const_ptr = LLVMBuildBitCast(builder, const_ptr,
 566                                 LLVMPointerType(vec_type, 0), "");
 567
 568    for(chan = 0; chan < 4; ++chan) {
 569       LLVMValueRef index = LLVMConstInt(LLVMInt32Type(), chan, 0);
 570       con[chan] = LLVMBuildLoad(builder, LLVMBuildGEP(builder, const_ptr, &index, 1, ""), "");
 571
 572       dst[chan] = LLVMBuildLoad(builder, LLVMBuildGEP(builder, dst_ptr, &index, 1, ""), "");
 573
 574       lp_build_name(con[chan], "con.%c", "rgba"[chan]);
 575       lp_build_name(dst[chan], "dst.%c", "rgba"[chan]);
 576    }
 577
 578    lp_build_blend_soa(builder, blend, type, src, dst, con, res);
 579
 580    for(chan = 0; chan < 4; ++chan) {
 581       if(blend->rt[0].colormask & (1 << chan)) {
 582          LLVMValueRef index = LLVMConstInt(LLVMInt32Type(), chan, 0);
 583          lp_build_name(res[chan], "res.%c", "rgba"[chan]);
 584          res[chan] = lp_build_select(&bld, mask, res[chan], dst[chan]);
 585          LLVMBuildStore(builder, res[chan], LLVMBuildGEP(builder, dst_ptr, &index, 1, ""));
 586       }
 587    }
 588
 589    lp_build_mask_end(&mask_ctx);
 590    lp_build_flow_destroy(flow);
 591 }
 592
 593
 594 /** casting function to avoid compiler warnings */
 595 static lp_jit_frag_func
 596 cast_voidptr_to_lp_jit_frag_func(void *p)
 597 {
 598    union {
 599       void *v;
 600       lp_jit_frag_func f;
 601    } tmp;
 602    assert(sizeof(tmp.v) == sizeof(tmp.f));
 603    tmp.v = p;
 604    return tmp.f;
 605 }
 606
 607
 608 /**
 609  * Generate the runtime callable function for the whole fragment pipeline.
 610  * Note that the function which we generate operates on a block of 16
 611  * pixels at at time.  The block contains 2x2 quads.  Each quad contains
 612  * 2x2 pixels.
 613  */
 614 static void
 615 generate_fragment(struct llvmpipe_context *lp,
 616                   struct lp_fragment_shader *shader,
 617                   struct lp_fragment_shader_variant *variant,
 618                   unsigned do_tri_test)
 619 {
 620    struct llvmpipe_screen *screen = llvmpipe_screen(lp->pipe.screen);
 621    const struct lp_fragment_shader_variant_key *key = &variant->key;
 622    struct lp_type fs_type;
 623    struct lp_type blend_type;
 624    LLVMTypeRef fs_elem_type;
 625    LLVMTypeRef fs_vec_type;
 626    LLVMTypeRef fs_int_vec_type;
 627    LLVMTypeRef blend_vec_type;
 628    LLVMTypeRef blend_int_vec_type;
 629    LLVMTypeRef arg_types[14];
 630    LLVMTypeRef func_type;
 631    LLVMTypeRef int32_vec4_type = lp_build_int32_vec4_type();
 632    LLVMValueRef context_ptr;
 633    LLVMValueRef x;
 634    LLVMValueRef y;
 635    LLVMValueRef a0_ptr;
 636    LLVMValueRef dadx_ptr;
 637    LLVMValueRef dady_ptr;
 638    LLVMValueRef color_ptr_ptr;
 639    LLVMValueRef depth_ptr;
 640    LLVMValueRef c0, c1, c2, step0_ptr, step1_ptr, step2_ptr;
 641    LLVMBasicBlockRef block;
 642    LLVMBuilderRef builder;
 643    LLVMValueRef x0;
 644    LLVMValueRef y0;
 645    struct lp_build_sampler_soa *sampler;
 646    struct lp_build_interp_soa_context interp;
 647    LLVMValueRef fs_mask[LP_MAX_VECTOR_LENGTH];
 648    LLVMValueRef fs_out_color[PIPE_MAX_COLOR_BUFS][NUM_CHANNELS][LP_MAX_VECTOR_LENGTH];
 649    LLVMValueRef blend_mask;
 650    LLVMValueRef blend_in_color[NUM_CHANNELS];
 651    LLVMValueRef function;
 652    unsigned num_fs;
 653    unsigned i;
 654    unsigned chan;
 655    unsigned cbuf;
 656
 657
 658    /* TODO: actually pick these based on the fs and color buffer
 659     * characteristics. */
 660
 661    memset(&fs_type, 0, sizeof fs_type);
 662    fs_type.floating = TRUE; /* floating point values */
 663    fs_type.sign = TRUE;     /* values are signed */
 664    fs_type.norm = FALSE;    /* values are not limited to [0,1] or [-1,1] */
 665    fs_type.width = 32;      /* 32-bit float */
 666    fs_type.length = 4;      /* 4 elements per vector */
 667    num_fs = 4;              /* number of quads per block */
 668
 669    memset(&blend_type, 0, sizeof blend_type);
 670    blend_type.floating = FALSE; /* values are integers */
 671    blend_type.sign = FALSE;     /* values are unsigned */
 672    blend_type.norm = TRUE;      /* values are in [0,1] or [-1,1] */
 673    blend_type.width = 8;        /* 8-bit ubyte values */
 674    blend_type.length = 16;      /* 16 elements per vector */
 675
 676    /*
 677     * Generate the function prototype. Any change here must be reflected in
 678     * lp_jit.h's lp_jit_frag_func function pointer type, and vice-versa.
 679     */
 680
 681    fs_elem_type = lp_build_elem_type(fs_type);
 682    fs_vec_type = lp_build_vec_type(fs_type);
 683    fs_int_vec_type = lp_build_int_vec_type(fs_type);
 684
 685    blend_vec_type = lp_build_vec_type(blend_type);
 686    blend_int_vec_type = lp_build_int_vec_type(blend_type);
 687
 688    arg_types[0] = screen->context_ptr_type;            /* context */
 689    arg_types[1] = LLVMInt32Type();                     /* x */
 690    arg_types[2] = LLVMInt32Type();                     /* y */
 691    arg_types[3] = LLVMPointerType(fs_elem_type, 0);    /* a0 */
 692    arg_types[4] = LLVMPointerType(fs_elem_type, 0);    /* dadx */
 693    arg_types[5] = LLVMPointerType(fs_elem_type, 0);    /* dady */
 694    arg_types[6] = LLVMPointerType(LLVMPointerType(blend_vec_type, 0), 0);  /* color */
 695    arg_types[7] = LLVMPointerType(fs_int_vec_type, 0); /* depth */
 696    arg_types[8] = LLVMInt32Type();                     /* c0 */
 697    arg_types[9] = LLVMInt32Type();                     /* c1 */
 698    arg_types[10] = LLVMInt32Type();                    /* c2 */
 699    /* Note: the step arrays are built as int32[16] but we interpret
 700     * them here as int32_vec4[4].
 701     */
 702    arg_types[11] = LLVMPointerType(int32_vec4_type, 0);/* step0 */
 703    arg_types[12] = LLVMPointerType(int32_vec4_type, 0);/* step1 */
 704    arg_types[13] = LLVMPointerType(int32_vec4_type, 0);/* step2 */
 705
 706    func_type = LLVMFunctionType(LLVMVoidType(), arg_types, Elements(arg_types), 0);
 707
 708    function = LLVMAddFunction(screen->module, "shader", func_type);
 709    LLVMSetFunctionCallConv(function, LLVMCCallConv);
 710
 711    variant->function[do_tri_test] = function;
 712
 713
 714    /* XXX: need to propagate noalias down into color param now we are
 715     * passing a pointer-to-pointer?
 716     */
 717    for(i = 0; i < Elements(arg_types); ++i)
 718       if(LLVMGetTypeKind(arg_types[i]) == LLVMPointerTypeKind)
 719          LLVMAddAttribute(LLVMGetParam(function, i), LLVMNoAliasAttribute);
 720
 721    context_ptr  = LLVMGetParam(function, 0);
 722    x            = LLVMGetParam(function, 1);
 723    y            = LLVMGetParam(function, 2);
 724    a0_ptr       = LLVMGetParam(function, 3);
 725    dadx_ptr     = LLVMGetParam(function, 4);
 726    dady_ptr     = LLVMGetParam(function, 5);
 727    color_ptr_ptr = LLVMGetParam(function, 6);
 728    depth_ptr    = LLVMGetParam(function, 7);
 729    c0           = LLVMGetParam(function, 8);
 730    c1           = LLVMGetParam(function, 9);
 731    c2           = LLVMGetParam(function, 10);
 732    step0_ptr    = LLVMGetParam(function, 11);
 733    step1_ptr    = LLVMGetParam(function, 12);
 734    step2_ptr    = LLVMGetParam(function, 13);
 735
 736    lp_build_name(context_ptr, "context");
 737    lp_build_name(x, "x");
 738    lp_build_name(y, "y");
 739    lp_build_name(a0_ptr, "a0");
 740    lp_build_name(dadx_ptr, "dadx");
 741    lp_build_name(dady_ptr, "dady");
 742    lp_build_name(color_ptr_ptr, "color_ptr");
 743    lp_build_name(depth_ptr, "depth");
 744    lp_build_name(c0, "c0");
 745    lp_build_name(c1, "c1");
 746    lp_build_name(c2, "c2");
 747    lp_build_name(step0_ptr, "step0");
 748    lp_build_name(step1_ptr, "step1");
 749    lp_build_name(step2_ptr, "step2");
 750
 751    /*
 752     * Function body
 753     */
 754
 755    block = LLVMAppendBasicBlock(function, "entry");
 756    builder = LLVMCreateBuilder();
 757    LLVMPositionBuilderAtEnd(builder, block);
 758
 759    generate_pos0(builder, x, y, &x0, &y0);
 760
 761    lp_build_interp_soa_init(&interp,
 762                             shader->base.tokens,
 763                             key->flatshade,
 764                             builder, fs_type,
 765                             a0_ptr, dadx_ptr, dady_ptr,
 766                             x0, y0);
 767
 768    /* code generated texture sampling */
 769    sampler = lp_llvm_sampler_soa_create(key->sampler, context_ptr);
 770
 771    /* loop over quads in the block */
 772    for(i = 0; i < num_fs; ++i) {
 773       LLVMValueRef index = LLVMConstInt(LLVMInt32Type(), i, 0);
 774       LLVMValueRef out_color[PIPE_MAX_COLOR_BUFS][NUM_CHANNELS];
 775       LLVMValueRef depth_ptr_i;
 776       int cbuf;
 777
 778       if(i != 0)
 779          lp_build_interp_soa_update(&interp, i);
 780
 781       depth_ptr_i = LLVMBuildGEP(builder, depth_ptr, &index, 1, "");
 782
 783       generate_fs(lp, shader, key,
 784                   builder,
 785                   fs_type,
 786                   context_ptr,
 787                   i,
 788                   &interp,
 789                   sampler,
 790                   &fs_mask[i], /* output */
 791                   out_color,
 792                   depth_ptr_i,
 793                   do_tri_test,
 794                   c0, c1, c2,
 795                   step0_ptr, step1_ptr, step2_ptr);
 796
 797       for(cbuf = 0; cbuf < key->nr_cbufs; cbuf++)
 798          for(chan = 0; chan < NUM_CHANNELS; ++chan)
 799             fs_out_color[cbuf][chan][i] = out_color[cbuf][chan];
 800    }
 801
 802    sampler->destroy(sampler);
 803
 804    /* Loop over color outputs / color buffers to do blending.
 805     */
 806    for(cbuf = 0; cbuf < key->nr_cbufs; cbuf++) {
 807       LLVMValueRef color_ptr;
 808       LLVMValueRef index = LLVMConstInt(LLVMInt32Type(), cbuf, 0);
 809
 810       /*
 811        * Convert the fs's output color and mask to fit to the blending type.
 812        */
 813       for(chan = 0; chan < NUM_CHANNELS; ++chan) {
 814          lp_build_conv(builder, fs_type, blend_type,
 815                        fs_out_color[cbuf][chan], num_fs,
 816                        &blend_in_color[chan], 1);
 817          lp_build_name(blend_in_color[chan], "color%d.%c", cbuf, "rgba"[chan]);
 818       }
 819
 820       lp_build_conv_mask(builder, fs_type, blend_type,
 821                          fs_mask, num_fs,
 822                          &blend_mask, 1);
 823
 824       color_ptr = LLVMBuildLoad(builder,
 825                                 LLVMBuildGEP(builder, color_ptr_ptr, &index, 1, ""),
 826                                 "");
 827       lp_build_name(color_ptr, "color_ptr%d", cbuf);
 828
 829       /*
 830        * Blending.
 831        */
 832       generate_blend(&key->blend,
 833                      builder,
 834                      blend_type,
 835                      context_ptr,
 836                      blend_mask,
 837                      blend_in_color,
 838                      color_ptr);
 839    }
 840
 841    LLVMBuildRetVoid(builder);
 842
 843    LLVMDisposeBuilder(builder);
 844
 845
 846    /* Verify the LLVM IR.  If invalid, dump and abort */
 847 #ifdef DEBUG
 848    if(LLVMVerifyFunction(function, LLVMPrintMessageAction)) {
 849       if (1)
 850          LLVMDumpValue(function);
 851       abort();
 852    }
 853 #endif
 854
 855    /* Apply optimizations to LLVM IR */
 856    if (1)
 857       LLVMRunFunctionPassManager(screen->pass, function);
 858
 859    if (LP_DEBUG & DEBUG_JIT) {
 860       /* Print the LLVM IR to stderr */
 861       LLVMDumpValue(function);
 862       debug_printf("\n");
 863    }
 864
 865    /*
 866     * Translate the LLVM IR into machine code.
 867     */
 868    {
 869       void *f = LLVMGetPointerToGlobal(screen->engine, function);
 870
 871       variant->jit_function[do_tri_test] = cast_voidptr_to_lp_jit_frag_func(f);
 872
 873       if (LP_DEBUG & DEBUG_ASM)
 874          lp_disassemble(f);
 875    }
 876 }
 877
 878
 879 static struct lp_fragment_shader_variant *
 880 generate_variant(struct llvmpipe_context *lp,
 881                  struct lp_fragment_shader *shader,
 882                  const struct lp_fragment_shader_variant_key *key)
 883 {
 884    struct lp_fragment_shader_variant *variant;
 885
 886    if (LP_DEBUG & DEBUG_JIT) {
 887       unsigned i;
 888
 889       tgsi_dump(shader->base.tokens, 0);
 890       if(key->depth.enabled) {
 891          debug_printf("depth.format = %s\n", util_format_name(key->zsbuf_format));
 892          debug_printf("depth.func = %s\n", util_dump_func(key->depth.func, TRUE));
 893          debug_printf("depth.writemask = %u\n", key->depth.writemask);
 894       }
 895       if(key->alpha.enabled) {
 896          debug_printf("alpha.func = %s\n", util_dump_func(key->alpha.func, TRUE));
 897          debug_printf("alpha.ref_value = %f\n", key->alpha.ref_value);
 898       }
 899       if(key->blend.logicop_enable) {
 900          debug_printf("blend.logicop_func = %u\n", key->blend.logicop_func);
 901       }
 902       else if(key->blend.rt[0].blend_enable) {
 903          debug_printf("blend.rgb_func = %s\n",   util_dump_blend_func  (key->blend.rt[0].rgb_func, TRUE));
 904          debug_printf("rgb_src_factor = %s\n",   util_dump_blend_factor(key->blend.rt[0].rgb_src_factor, TRUE));
 905          debug_printf("rgb_dst_factor = %s\n",   util_dump_blend_factor(key->blend.rt[0].rgb_dst_factor, TRUE));
 906          debug_printf("alpha_func = %s\n",       util_dump_blend_func  (key->blend.rt[0].alpha_func, TRUE));
 907          debug_printf("alpha_src_factor = %s\n", util_dump_blend_factor(key->blend.rt[0].alpha_src_factor, TRUE));
 908          debug_printf("alpha_dst_factor = %s\n", util_dump_blend_factor(key->blend.rt[0].alpha_dst_factor, TRUE));
 909       }
 910       debug_printf("blend.colormask = 0x%x\n", key->blend.rt[0].colormask);
 911       for(i = 0; i < PIPE_MAX_SAMPLERS; ++i) {
 912          if(key->sampler[i].format) {
 913             debug_printf("sampler[%u] = \n", i);
 914             debug_printf("  .format = %s\n",
 915                          util_format_name(key->sampler[i].format));
 916             debug_printf("  .target = %s\n",
 917                          util_dump_tex_target(key->sampler[i].target, TRUE));
 918             debug_printf("  .pot = %u %u %u\n",
 919                          key->sampler[i].pot_width,
 920                          key->sampler[i].pot_height,
 921                          key->sampler[i].pot_depth);
 922             debug_printf("  .wrap = %s %s %s\n",
 923                          util_dump_tex_wrap(key->sampler[i].wrap_s, TRUE),
 924                          util_dump_tex_wrap(key->sampler[i].wrap_t, TRUE),
 925                          util_dump_tex_wrap(key->sampler[i].wrap_r, TRUE));
 926             debug_printf("  .min_img_filter = %s\n",
 927                          util_dump_tex_filter(key->sampler[i].min_img_filter, TRUE));
 928             debug_printf("  .min_mip_filter = %s\n",
 929                          util_dump_tex_mipfilter(key->sampler[i].min_mip_filter, TRUE));
 930             debug_printf("  .mag_img_filter = %s\n",
 931                          util_dump_tex_filter(key->sampler[i].mag_img_filter, TRUE));
 932             if(key->sampler[i].compare_mode != PIPE_TEX_COMPARE_NONE)
 933                debug_printf("  .compare_func = %s\n", util_dump_func(key->sampler[i].compare_func, TRUE));
 934             debug_printf("  .normalized_coords = %u\n", key->sampler[i].normalized_coords);
 935          }
 936       }
 937    }
 938
 939    variant = CALLOC_STRUCT(lp_fragment_shader_variant);
 940    if(!variant)
 941       return NULL;
 942
 943    variant->shader = shader;
 944    memcpy(&variant->key, key, sizeof *key);
 945
 946    generate_fragment(lp, shader, variant, 0);
 947    generate_fragment(lp, shader, variant, 1);
 948
 949    /* insert new variant into linked list */
 950    variant->next = shader->variants;
 951    shader->variants = variant;
 952
 953    return variant;
 954 }
 955
 956
 957 void *
 958 llvmpipe_create_fs_state(struct pipe_context *pipe,
 959                          const struct pipe_shader_state *templ)
 960 {
 961    struct lp_fragment_shader *shader;
 962
 963    shader = CALLOC_STRUCT(lp_fragment_shader);
 964    if (!shader)
 965       return NULL;
 966
 967    /* get/save the summary info for this shader */
 968    tgsi_scan_shader(templ->tokens, &shader->info);
 969
 970    /* we need to keep a local copy of the tokens */
 971    shader->base.tokens = tgsi_dup_tokens(templ->tokens);
 972
 973    return shader;
 974 }
 975
 976
 977 void
 978 llvmpipe_bind_fs_state(struct pipe_context *pipe, void *fs)
 979 {
 980    struct llvmpipe_context *llvmpipe = llvmpipe_context(pipe);
 981
 982    if (llvmpipe->fs == fs)
 983       return;
 984
 985    draw_flush(llvmpipe->draw);
 986
 987    llvmpipe->fs = fs;
 988
 989    llvmpipe->dirty |= LP_NEW_FS;
 990 }
 991
 992
 993 void
 994 llvmpipe_delete_fs_state(struct pipe_context *pipe, void *fs)
 995 {
 996    struct llvmpipe_context *llvmpipe = llvmpipe_context(pipe);
 997    struct llvmpipe_screen *screen = llvmpipe_screen(pipe->screen);
 998    struct lp_fragment_shader *shader = fs;
 999    struct lp_fragment_shader_variant *variant;
1000
1001    assert(fs != llvmpipe->fs);
1002    (void) llvmpipe;
1003
1004    /*
1005     * XXX: we need to flush the context until we have some sort of reference
1006     * counting in fragment shaders as they may still be binned
1007     */
1008    draw_flush(llvmpipe->draw);
1009    lp_setup_flush(llvmpipe->setup, 0);
1010
1011    variant = shader->variants;
1012    while(variant) {
1013       struct lp_fragment_shader_variant *next = variant->next;
1014       unsigned i;
1015
1016       for (i = 0; i < Elements(variant->function); i++) {
1017          if (variant->function[i]) {
1018             if (variant->jit_function[i])
1019                LLVMFreeMachineCodeForFunction(screen->engine,
1020                                               variant->function[i]);
1021             LLVMDeleteFunction(variant->function[i]);
1022          }
1023       }
1024
1025       FREE(variant);
1026
1027       variant = next;
1028    }
1029
1030    FREE((void *) shader->base.tokens);
1031    FREE(shader);
1032 }
1033
1034
1035
1036 void
1037 llvmpipe_set_constant_buffer(struct pipe_context *pipe,
1038                              uint shader, uint index,
1039                              struct pipe_buffer *constants)
1040 {
1041    struct llvmpipe_context *llvmpipe = llvmpipe_context(pipe);
1042    unsigned size = constants ? constants->size : 0;
1043    const void *data = constants ? llvmpipe_buffer(constants)->data : NULL;
1044
1045    assert(shader < PIPE_SHADER_TYPES);
1046    assert(index == 0);
1047
1048    if(llvmpipe->constants[shader] == constants)
1049       return;
1050
1051    draw_flush(llvmpipe->draw);
1052
1053    /* note: reference counting */
1054    pipe_buffer_reference(&llvmpipe->constants[shader], constants);
1055
1056    if(shader == PIPE_SHADER_VERTEX) {
1057       draw_set_mapped_constant_buffer(llvmpipe->draw, PIPE_SHADER_VERTEX, 0,
1058                                       data, size);
1059    }
1060
1061    llvmpipe->dirty |= LP_NEW_CONSTANTS;
1062 }
1063
1064
1065 /**
1066  * We need to generate several variants of the fragment pipeline to match
1067  * all the combinations of the contributing state atoms.
1068  *
1069  * TODO: there is actually no reason to tie this to context state -- the
1070  * generated code could be cached globally in the screen.
1071  */
1072 static void
1073 make_variant_key(struct llvmpipe_context *lp,
1074                  struct lp_fragment_shader *shader,
1075                  struct lp_fragment_shader_variant_key *key)
1076 {
1077    unsigned i;
1078
1079    memset(key, 0, sizeof *key);
1080
1081    if (lp->framebuffer.zsbuf) {
1082       if (lp->depth_stencil->depth.enabled) {
1083          key->zsbuf_format = lp->framebuffer.zsbuf->format;
1084          memcpy(&key->depth, &lp->depth_stencil->depth, sizeof key->depth);
1085       }
1086       if (lp->depth_stencil->stencil[0].enabled) {
1087          key->zsbuf_format = lp->framebuffer.zsbuf->format;
1088          memcpy(&key->stencil, &lp->depth_stencil->stencil, sizeof key->stencil);
1089       }
1090    }
1091
1092    key->alpha.enabled = lp->depth_stencil->alpha.enabled;
1093    if(key->alpha.enabled)
1094       key->alpha.func = lp->depth_stencil->alpha.func;
1095    /* alpha.ref_value is passed in jit_context */
1096
1097    key->flatshade = lp->rasterizer->flatshade;
1098    key->scissor = lp->rasterizer->scissor;
1099
1100    if (lp->framebuffer.nr_cbufs) {
1101       memcpy(&key->blend, lp->blend, sizeof key->blend);
1102    }
1103
1104    key->nr_cbufs = lp->framebuffer.nr_cbufs;
1105    for (i = 0; i < lp->framebuffer.nr_cbufs; i++) {
1106       const struct util_format_description *format_desc;
1107       unsigned chan;
1108
1109       format_desc = util_format_description(lp->framebuffer.cbufs[i]->format);
1110       assert(format_desc->layout == UTIL_FORMAT_COLORSPACE_RGB ||
1111              format_desc->layout == UTIL_FORMAT_COLORSPACE_SRGB);
1112
1113       /* mask out color channels not present in the color buffer.
1114        * Should be simple to incorporate per-cbuf writemasks:
1115        */
1116       for(chan = 0; chan < 4; ++chan) {
1117          enum util_format_swizzle swizzle = format_desc->swizzle[chan];
1118
1119          if(swizzle <= UTIL_FORMAT_SWIZZLE_W)
1120             key->blend.rt[0].colormask |= (1 << chan);
1121       }
1122    }
1123
1124    for(i = 0; i < PIPE_MAX_SAMPLERS; ++i)
1125       if(shader->info.file_mask[TGSI_FILE_SAMPLER] & (1 << i))
1126          lp_sampler_static_state(&key->sampler[i], lp->fragment_sampler_views[i]->texture, lp->sampler[i]);
1127 }
1128
1129
1130 /**
1131  * Update fragment state.  This is called just prior to drawing
1132  * something when some fragment-related state has changed.
1133  */
1134 void
1135 llvmpipe_update_fs(struct llvmpipe_context *lp)
1136 {
1137    struct lp_fragment_shader *shader = lp->fs;
1138    struct lp_fragment_shader_variant_key key;
1139    struct lp_fragment_shader_variant *variant;
1140    boolean opaque;
1141
1142    make_variant_key(lp, shader, &key);
1143
1144    variant = shader->variants;
1145    while(variant) {
1146       if(memcmp(&variant->key, &key, sizeof key) == 0)
1147          break;
1148
1149       variant = variant->next;
1150    }
1151
1152    if (!variant) {
1153       int64_t t0, t1;
1154       int64_t dt;
1155       t0 = os_time_get();
1156
1157       variant = generate_variant(lp, shader, &key);
1158
1159       t1 = os_time_get();
1160       dt = t1 - t0;
1161       LP_COUNT_ADD(llvm_compile_time, dt);
1162       LP_COUNT_ADD(nr_llvm_compiles, 2);  /* emit vs. omit in/out test */
1163    }
1164
1165    shader->current = variant;
1166
1167    /* TODO: put this in the variant */
1168    /* TODO: most of these can be relaxed, in particular the colormask */
1169    opaque = !key.blend.logicop_enable &&
1170             !key.blend.rt[0].blend_enable &&
1171             key.blend.rt[0].colormask == 0xf &&
1172             !key.alpha.enabled &&
1173             !key.depth.enabled &&
1174             !key.scissor &&
1175             !shader->info.uses_kill
1176             ? TRUE : FALSE;
1177
1178    lp_setup_set_fs_functions(lp->setup,
1179                              shader->current->jit_function[0],
1180                              shader->current->jit_function[1],
1181                              opaque);
1182 }