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    1 /*
    2  * Copyright 2008 Corbin Simpson <MostAwesomeDude@gmail.com>
    3  *                Joakim Sindholt <opensource@zhasha.com>
    4  * Copyright 2009 Marek Olšák <maraeo@gmail.com>
    5  *
    6  * Permission is hereby granted, free of charge, to any person obtaining a
    7  * copy of this software and associated documentation files (the "Software"),
    8  * to deal in the Software without restriction, including without limitation
    9  * on the rights to use, copy, modify, merge, publish, distribute, sub
   10  * license, and/or sell copies of the Software, and to permit persons to whom
   11  * the Software is furnished to do so, subject to the following conditions:
   12  *
   13  * The above copyright notice and this permission notice (including the next
   14  * paragraph) shall be included in all copies or substantial portions of the
   15  * Software.
   16  *
   17  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   18  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   19  * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
   20  * THE AUTHOR(S) AND/OR THEIR SUPPLIERS BE LIABLE FOR ANY CLAIM,
   21  * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
   22  * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
   23  * USE OR OTHER DEALINGS IN THE SOFTWARE. */
   24 
   25 #include "util/format/u_format.h"
   26 #include "util/u_math.h"
   27 #include "util/u_memory.h"
   28 
   29 #include "tgsi/tgsi_dump.h"
   30 #include "tgsi/tgsi_ureg.h"
   31 
   32 #include "r300_cb.h"
   33 #include "r300_context.h"
   34 #include "r300_emit.h"
   35 #include "r300_screen.h"
   36 #include "r300_fs.h"
   37 #include "r300_reg.h"
   38 #include "r300_texture.h"
   39 #include "r300_tgsi_to_rc.h"
   40 
   41 #include "compiler/radeon_compiler.h"
   42 
   43 /* Convert info about FS input semantics to r300_shader_semantics. */
   44 void r300_shader_read_fs_inputs(struct tgsi_shader_info* info,
   45                                 struct r300_shader_semantics* fs_inputs)
   46 {
   47     int i;
   48     unsigned index;
   49 
   50     r300_shader_semantics_reset(fs_inputs);
   51 
   52     for (i = 0; i < info->num_inputs; i++) {
   53         index = info->input_semantic_index[i];
   54 
   55         switch (info->input_semantic_name[i]) {
   56             case TGSI_SEMANTIC_COLOR:
   57                 assert(index < ATTR_COLOR_COUNT);
   58                 fs_inputs->color[index] = i;
   59                 break;
   60 
   61             case TGSI_SEMANTIC_GENERIC:
   62                 assert(index < ATTR_GENERIC_COUNT);
   63                 fs_inputs->generic[index] = i;
   64                 break;
   65 
   66             case TGSI_SEMANTIC_FOG:
   67                 assert(index == 0);
   68                 fs_inputs->fog = i;
   69                 break;
   70 
   71             case TGSI_SEMANTIC_POSITION:
   72                 assert(index == 0);
   73                 fs_inputs->wpos = i;
   74                 break;
   75 
   76             case TGSI_SEMANTIC_FACE:
   77                 assert(index == 0);
   78                 fs_inputs->face = i;
   79                 break;
   80 
   81             default:
   82                 fprintf(stderr, "r300: FP: Unknown input semantic: %i\n",
   83                         info->input_semantic_name[i]);
   84         }
   85     }
   86 }
   87 
   88 static void find_output_registers(struct r300_fragment_program_compiler * compiler,
   89                                   struct r300_fragment_shader_code *shader)
   90 {
   91     unsigned i, colorbuf_count = 0;
   92 
   93     /* Mark the outputs as not present initially */
   94     compiler->OutputColor[0] = shader->info.num_outputs;
   95     compiler->OutputColor[1] = shader->info.num_outputs;
   96     compiler->OutputColor[2] = shader->info.num_outputs;
   97     compiler->OutputColor[3] = shader->info.num_outputs;
   98     compiler->OutputDepth = shader->info.num_outputs;
   99 
  100     /* Now see where they really are. */
  101     for(i = 0; i < shader->info.num_outputs; ++i) {
  102         switch(shader->info.output_semantic_name[i]) {
  103             case TGSI_SEMANTIC_COLOR:
  104                 compiler->OutputColor[colorbuf_count] = i;
  105                 colorbuf_count++;
  106                 break;
  107             case TGSI_SEMANTIC_POSITION:
  108                 compiler->OutputDepth = i;
  109                 break;
  110         }
  111     }
  112 }
  113 
  114 static void allocate_hardware_inputs(
  115     struct r300_fragment_program_compiler * c,
  116     void (*allocate)(void * data, unsigned input, unsigned hwreg),
  117     void * mydata)
  118 {
  119     struct r300_shader_semantics* inputs =
  120         (struct r300_shader_semantics*)c->UserData;
  121     int i, reg = 0;
  122 
  123     /* Allocate input registers. */
  124     for (i = 0; i < ATTR_COLOR_COUNT; i++) {
  125         if (inputs->color[i] != ATTR_UNUSED) {
  126             allocate(mydata, inputs->color[i], reg++);
  127         }
  128     }
  129     if (inputs->face != ATTR_UNUSED) {
  130         allocate(mydata, inputs->face, reg++);
  131     }
  132     for (i = 0; i < ATTR_GENERIC_COUNT; i++) {
  133         if (inputs->generic[i] != ATTR_UNUSED) {
  134             allocate(mydata, inputs->generic[i], reg++);
  135         }
  136     }
  137     if (inputs->fog != ATTR_UNUSED) {
  138         allocate(mydata, inputs->fog, reg++);
  139     }
  140     if (inputs->wpos != ATTR_UNUSED) {
  141         allocate(mydata, inputs->wpos, reg++);
  142     }
  143 }
  144 
  145 static void get_external_state(
  146     struct r300_context* r300,
  147     struct r300_fragment_program_external_state* state)
  148 {
  149     struct r300_textures_state *texstate = r300->textures_state.state;
  150     unsigned i;
  151 
  152     state->alpha_to_one = r300->alpha_to_one && r300->msaa_enable;
  153 
  154     for (i = 0; i < texstate->sampler_state_count; i++) {
  155         struct r300_sampler_state *s = texstate->sampler_states[i];
  156         struct r300_sampler_view *v = texstate->sampler_views[i];
  157         struct r300_resource *t;
  158 
  159         if (!s || !v) {
  160             continue;
  161         }
  162 
  163         t = r300_resource(v->base.texture);
  164 
  165         if (s->state.compare_mode == PIPE_TEX_COMPARE_R_TO_TEXTURE) {
  166             state->unit[i].compare_mode_enabled = 1;
  167 
  168             /* Fortunately, no need to translate this. */
  169             state->unit[i].texture_compare_func = s->state.compare_func;
  170         }
  171 
  172         state->unit[i].non_normalized_coords = !s->state.normalized_coords;
  173 
  174         /* Pass texture swizzling to the compiler, some lowering passes need it. */
  175         if (state->unit[i].compare_mode_enabled) {
  176             state->unit[i].texture_swizzle =
  177                 RC_MAKE_SWIZZLE(v->swizzle[0], v->swizzle[1],
  178                                 v->swizzle[2], v->swizzle[3]);
  179         }
  180 
  181         /* XXX this should probably take into account STR, not just S. */
  182         if (t->tex.is_npot) {
  183             switch (s->state.wrap_s) {
  184             case PIPE_TEX_WRAP_REPEAT:
  185                 state->unit[i].wrap_mode = RC_WRAP_REPEAT;
  186                 break;
  187 
  188             case PIPE_TEX_WRAP_MIRROR_REPEAT:
  189                 state->unit[i].wrap_mode = RC_WRAP_MIRRORED_REPEAT;
  190                 break;
  191 
  192             case PIPE_TEX_WRAP_MIRROR_CLAMP:
  193             case PIPE_TEX_WRAP_MIRROR_CLAMP_TO_EDGE:
  194             case PIPE_TEX_WRAP_MIRROR_CLAMP_TO_BORDER:
  195                 state->unit[i].wrap_mode = RC_WRAP_MIRRORED_CLAMP;
  196                 break;
  197 
  198             default:
  199                 state->unit[i].wrap_mode = RC_WRAP_NONE;
  200             }
  201 
  202             if (t->b.b.target == PIPE_TEXTURE_3D)
  203                 state->unit[i].clamp_and_scale_before_fetch = TRUE;
  204         }
  205     }
  206 }
  207 
  208 static void r300_translate_fragment_shader(
  209     struct r300_context* r300,
  210     struct r300_fragment_shader_code* shader,
  211     const struct tgsi_token *tokens);
  212 
  213 static void r300_dummy_fragment_shader(
  214     struct r300_context* r300,
  215     struct r300_fragment_shader_code* shader)
  216 {
  217     struct pipe_shader_state state;
  218     struct ureg_program *ureg;
  219     struct ureg_dst out;
  220     struct ureg_src imm;
  221 
  222     /* Make a simple fragment shader which outputs (0, 0, 0, 1) */
  223     ureg = ureg_create(PIPE_SHADER_FRAGMENT);
  224     out = ureg_DECL_output(ureg, TGSI_SEMANTIC_COLOR, 0);
  225     imm = ureg_imm4f(ureg, 0, 0, 0, 1);
  226 
  227     ureg_MOV(ureg, out, imm);
  228     ureg_END(ureg);
  229 
  230     state.tokens = ureg_finalize(ureg);
  231 
  232     shader->dummy = TRUE;
  233     r300_translate_fragment_shader(r300, shader, state.tokens);
  234 
  235     ureg_destroy(ureg);
  236 }
  237 
  238 static void r300_emit_fs_code_to_buffer(
  239     struct r300_context *r300,
  240     struct r300_fragment_shader_code *shader)
  241 {
  242     struct rX00_fragment_program_code *generic_code = &shader->code;
  243     unsigned imm_count = shader->immediates_count;
  244     unsigned imm_first = shader->externals_count;
  245     unsigned imm_end = generic_code->constants.Count;
  246     struct rc_constant *constants = generic_code->constants.Constants;
  247     unsigned i;
  248     CB_LOCALS;
  249 
  250     if (r300->screen->caps.is_r500) {
  251         struct r500_fragment_program_code *code = &generic_code->code.r500;
  252 
  253         shader->cb_code_size = 19 +
  254                                ((code->inst_end + 1) * 6) +
  255                                imm_count * 7 +
  256                                code->int_constant_count * 2;
  257 
  258         NEW_CB(shader->cb_code, shader->cb_code_size);
  259         OUT_CB_REG(R500_US_CONFIG, R500_ZERO_TIMES_ANYTHING_EQUALS_ZERO);
  260         OUT_CB_REG(R500_US_PIXSIZE, code->max_temp_idx);
  261         OUT_CB_REG(R500_US_FC_CTRL, code->us_fc_ctrl);
  262         for(i = 0; i < code->int_constant_count; i++){
  263                 OUT_CB_REG(R500_US_FC_INT_CONST_0 + (i * 4),
  264                                                 code->int_constants[i]);
  265         }
  266         OUT_CB_REG(R500_US_CODE_RANGE,
  267                    R500_US_CODE_RANGE_ADDR(0) | R500_US_CODE_RANGE_SIZE(code->inst_end));
  268         OUT_CB_REG(R500_US_CODE_OFFSET, 0);
  269         OUT_CB_REG(R500_US_CODE_ADDR,
  270                    R500_US_CODE_START_ADDR(0) | R500_US_CODE_END_ADDR(code->inst_end));
  271 
  272         OUT_CB_REG(R500_GA_US_VECTOR_INDEX, R500_GA_US_VECTOR_INDEX_TYPE_INSTR);
  273         OUT_CB_ONE_REG(R500_GA_US_VECTOR_DATA, (code->inst_end + 1) * 6);
  274         for (i = 0; i <= code->inst_end; i++) {
  275             OUT_CB(code->inst[i].inst0);
  276             OUT_CB(code->inst[i].inst1);
  277             OUT_CB(code->inst[i].inst2);
  278             OUT_CB(code->inst[i].inst3);
  279             OUT_CB(code->inst[i].inst4);
  280             OUT_CB(code->inst[i].inst5);
  281         }
  282 
  283         /* Emit immediates. */
  284         if (imm_count) {
  285             for(i = imm_first; i < imm_end; ++i) {
  286                 if (constants[i].Type == RC_CONSTANT_IMMEDIATE) {
  287                     const float *data = constants[i].u.Immediate;
  288 
  289                     OUT_CB_REG(R500_GA_US_VECTOR_INDEX,
  290                                R500_GA_US_VECTOR_INDEX_TYPE_CONST |
  291                                (i & R500_GA_US_VECTOR_INDEX_MASK));
  292                     OUT_CB_ONE_REG(R500_GA_US_VECTOR_DATA, 4);
  293                     OUT_CB_TABLE(data, 4);
  294                 }
  295             }
  296         }
  297     } else { /* r300 */
  298         struct r300_fragment_program_code *code = &generic_code->code.r300;
  299         unsigned int alu_length = code->alu.length;
  300         unsigned int alu_iterations = ((alu_length - 1) / 64) + 1;
  301         unsigned int tex_length = code->tex.length;
  302         unsigned int tex_iterations =
  303             tex_length > 0 ? ((tex_length - 1) / 32) + 1 : 0;
  304         unsigned int iterations =
  305             alu_iterations > tex_iterations ? alu_iterations : tex_iterations;
  306         unsigned int bank = 0;
  307 
  308         shader->cb_code_size = 15 +
  309             /* R400_US_CODE_BANK */
  310             (r300->screen->caps.is_r400 ? 2 * (iterations + 1): 0) +
  311             /* R400_US_CODE_EXT */
  312             (r300->screen->caps.is_r400 ? 2 : 0) +
  313             /* R300_US_ALU_{RGB,ALPHA}_{INST,ADDR}_0, R400_US_ALU_EXT_ADDR_0 */
  314             (code->r390_mode ? (5 * alu_iterations) : 4) +
  315             /* R400_US_ALU_EXT_ADDR_[0-63] */
  316             (code->r390_mode ? (code->alu.length) : 0) +
  317             /* R300_US_ALU_{RGB,ALPHA}_{INST,ADDR}_0 */
  318             code->alu.length * 4 +
  319             /* R300_US_TEX_INST_0, R300_US_TEX_INST_[0-31] */
  320             (code->tex.length > 0 ? code->tex.length + tex_iterations : 0) +
  321             imm_count * 5;
  322 
  323         NEW_CB(shader->cb_code, shader->cb_code_size);
  324 
  325         OUT_CB_REG(R300_US_CONFIG, code->config);
  326         OUT_CB_REG(R300_US_PIXSIZE, code->pixsize);
  327         OUT_CB_REG(R300_US_CODE_OFFSET, code->code_offset);
  328 
  329         if (code->r390_mode) {
  330             OUT_CB_REG(R400_US_CODE_EXT, code->r400_code_offset_ext);
  331         } else if (r300->screen->caps.is_r400) {
  332             /* This register appears to affect shaders even if r390_mode is
  333              * disabled, so it needs to be set to 0 for shaders that
  334              * don't use r390_mode. */
  335             OUT_CB_REG(R400_US_CODE_EXT, 0);
  336         }
  337 
  338         OUT_CB_REG_SEQ(R300_US_CODE_ADDR_0, 4);
  339         OUT_CB_TABLE(code->code_addr, 4);
  340 
  341         do {
  342             unsigned int bank_alu_length = (alu_length < 64 ? alu_length : 64);
  343             unsigned int bank_alu_offset = bank * 64;
  344             unsigned int bank_tex_length = (tex_length < 32 ? tex_length : 32);
  345             unsigned int bank_tex_offset = bank * 32;
  346 
  347             if (r300->screen->caps.is_r400) {
  348                 OUT_CB_REG(R400_US_CODE_BANK, code->r390_mode ?
  349                                 (bank << R400_BANK_SHIFT) | R400_R390_MODE_ENABLE : 0);//2
  350             }
  351 
  352             if (bank_alu_length > 0) {
  353                 OUT_CB_REG_SEQ(R300_US_ALU_RGB_INST_0, bank_alu_length);
  354                 for (i = 0; i < bank_alu_length; i++)
  355                     OUT_CB(code->alu.inst[i + bank_alu_offset].rgb_inst);
  356 
  357                 OUT_CB_REG_SEQ(R300_US_ALU_RGB_ADDR_0, bank_alu_length);
  358                 for (i = 0; i < bank_alu_length; i++)
  359                     OUT_CB(code->alu.inst[i + bank_alu_offset].rgb_addr);
  360 
  361                 OUT_CB_REG_SEQ(R300_US_ALU_ALPHA_INST_0, bank_alu_length);
  362                 for (i = 0; i < bank_alu_length; i++)
  363                     OUT_CB(code->alu.inst[i + bank_alu_offset].alpha_inst);
  364 
  365                 OUT_CB_REG_SEQ(R300_US_ALU_ALPHA_ADDR_0, bank_alu_length);
  366                 for (i = 0; i < bank_alu_length; i++)
  367                     OUT_CB(code->alu.inst[i + bank_alu_offset].alpha_addr);
  368 
  369                 if (code->r390_mode) {
  370                     OUT_CB_REG_SEQ(R400_US_ALU_EXT_ADDR_0, bank_alu_length);
  371                     for (i = 0; i < bank_alu_length; i++)
  372                         OUT_CB(code->alu.inst[i + bank_alu_offset].r400_ext_addr);
  373                 }
  374             }
  375 
  376             if (bank_tex_length > 0) {
  377                 OUT_CB_REG_SEQ(R300_US_TEX_INST_0, bank_tex_length);
  378                 OUT_CB_TABLE(code->tex.inst + bank_tex_offset, bank_tex_length);
  379             }
  380 
  381             alu_length -= bank_alu_length;
  382             tex_length -= bank_tex_length;
  383             bank++;
  384         } while(code->r390_mode && (alu_length > 0 || tex_length > 0));
  385 
  386         /* R400_US_CODE_BANK needs to be reset to 0, otherwise some shaders
  387          * will be rendered incorrectly. */
  388         if (r300->screen->caps.is_r400) {
  389             OUT_CB_REG(R400_US_CODE_BANK,
  390                 code->r390_mode ? R400_R390_MODE_ENABLE : 0);
  391         }
  392 
  393         /* Emit immediates. */
  394         if (imm_count) {
  395             for(i = imm_first; i < imm_end; ++i) {
  396                 if (constants[i].Type == RC_CONSTANT_IMMEDIATE) {
  397                     const float *data = constants[i].u.Immediate;
  398 
  399                     OUT_CB_REG_SEQ(R300_PFS_PARAM_0_X + i * 16, 4);
  400                     OUT_CB(pack_float24(data[0]));
  401                     OUT_CB(pack_float24(data[1]));
  402                     OUT_CB(pack_float24(data[2]));
  403                     OUT_CB(pack_float24(data[3]));
  404                 }
  405             }
  406         }
  407     }
  408 
  409     OUT_CB_REG(R300_FG_DEPTH_SRC, shader->fg_depth_src);
  410     OUT_CB_REG(R300_US_W_FMT, shader->us_out_w);
  411     END_CB;
  412 }
  413 
  414 static void r300_translate_fragment_shader(
  415     struct r300_context* r300,
  416     struct r300_fragment_shader_code* shader,
  417     const struct tgsi_token *tokens)
  418 {
  419     struct r300_fragment_program_compiler compiler;
  420     struct tgsi_to_rc ttr;
  421     int wpos, face;
  422     unsigned i;
  423 
  424     tgsi_scan_shader(tokens, &shader->info);
  425     r300_shader_read_fs_inputs(&shader->info, &shader->inputs);
  426 
  427     wpos = shader->inputs.wpos;
  428     face = shader->inputs.face;
  429 
  430     /* Setup the compiler. */
  431     memset(&compiler, 0, sizeof(compiler));
  432     rc_init(&compiler.Base, &r300->fs_regalloc_state);
  433     DBG_ON(r300, DBG_FP) ? compiler.Base.Debug |= RC_DBG_LOG : 0;
  434     DBG_ON(r300, DBG_P_STAT) ? compiler.Base.Debug |= RC_DBG_STATS : 0;
  435 
  436     compiler.code = &shader->code;
  437     compiler.state = shader->compare_state;
  438     compiler.Base.is_r500 = r300->screen->caps.is_r500;
  439     compiler.Base.is_r400 = r300->screen->caps.is_r400;
  440     compiler.Base.disable_optimizations = DBG_ON(r300, DBG_NO_OPT);
  441     compiler.Base.has_half_swizzles = TRUE;
  442     compiler.Base.has_presub = TRUE;
  443     compiler.Base.has_omod = TRUE;
  444     compiler.Base.max_temp_regs =
  445         compiler.Base.is_r500 ? 128 : (compiler.Base.is_r400 ? 64 : 32);
  446     compiler.Base.max_constants = compiler.Base.is_r500 ? 256 : 32;
  447     compiler.Base.max_alu_insts =
  448         (compiler.Base.is_r500 || compiler.Base.is_r400) ? 512 : 64;
  449     compiler.Base.max_tex_insts =
  450         (compiler.Base.is_r500 || compiler.Base.is_r400) ? 512 : 32;
  451     compiler.AllocateHwInputs = &allocate_hardware_inputs;
  452     compiler.UserData = &shader->inputs;
  453 
  454     find_output_registers(&compiler, shader);
  455 
  456     shader->write_all =
  457           shader->info.properties[TGSI_PROPERTY_FS_COLOR0_WRITES_ALL_CBUFS];
  458 
  459     if (compiler.Base.Debug & RC_DBG_LOG) {
  460         DBG(r300, DBG_FP, "r300: Initial fragment program\n");
  461         tgsi_dump(tokens, 0);
  462     }
  463 
  464     /* Translate TGSI to our internal representation */
  465     ttr.compiler = &compiler.Base;
  466     ttr.info = &shader->info;
  467     ttr.use_half_swizzles = TRUE;
  468 
  469     r300_tgsi_to_rc(&ttr, tokens);
  470 
  471     if (ttr.error) {
  472         fprintf(stderr, "r300 FP: Cannot translate a shader. "
  473                 "Using a dummy shader instead.\n");
  474         r300_dummy_fragment_shader(r300, shader);
  475         return;
  476     }
  477 
  478     if (!r300->screen->caps.is_r500 ||
  479         compiler.Base.Program.Constants.Count > 200) {
  480         compiler.Base.remove_unused_constants = TRUE;
  481     }
  482 
  483     /**
  484      * Transform the program to support WPOS.
  485      *
  486      * Introduce a small fragment at the start of the program that will be
  487      * the only code that directly reads the WPOS input.
  488      * All other code pieces that reference that input will be rewritten
  489      * to read from a newly allocated temporary. */
  490     if (wpos != ATTR_UNUSED) {
  491         /* Moving the input to some other reg is not really necessary. */
  492         rc_transform_fragment_wpos(&compiler.Base, wpos, wpos, TRUE);
  493     }
  494 
  495     if (face != ATTR_UNUSED) {
  496         rc_transform_fragment_face(&compiler.Base, face);
  497     }
  498 
  499     /* Invoke the compiler */
  500     r3xx_compile_fragment_program(&compiler);
  501 
  502     if (compiler.Base.Error) {
  503         fprintf(stderr, "r300 FP: Compiler Error:\n%sUsing a dummy shader"
  504                 " instead.\n", compiler.Base.ErrorMsg);
  505 
  506         if (shader->dummy) {
  507             fprintf(stderr, "r300 FP: Cannot compile the dummy shader! "
  508                     "Giving up...\n");
  509             abort();
  510         }
  511 
  512         rc_destroy(&compiler.Base);
  513         r300_dummy_fragment_shader(r300, shader);
  514         return;
  515     }
  516 
  517     /* Shaders with zero instructions are invalid,
  518      * use the dummy shader instead. */
  519     if (shader->code.code.r500.inst_end == -1) {
  520         rc_destroy(&compiler.Base);
  521         r300_dummy_fragment_shader(r300, shader);
  522         return;
  523     }
  524 
  525     /* Initialize numbers of constants for each type. */
  526     shader->externals_count = 0;
  527     for (i = 0;
  528          i < shader->code.constants.Count &&
  529          shader->code.constants.Constants[i].Type == RC_CONSTANT_EXTERNAL; i++) {
  530         shader->externals_count = i+1;
  531     }
  532     shader->immediates_count = 0;
  533     shader->rc_state_count = 0;
  534 
  535     for (i = shader->externals_count; i < shader->code.constants.Count; i++) {
  536         switch (shader->code.constants.Constants[i].Type) {
  537             case RC_CONSTANT_IMMEDIATE:
  538                 ++shader->immediates_count;
  539                 break;
  540             case RC_CONSTANT_STATE:
  541                 ++shader->rc_state_count;
  542                 break;
  543             default:
  544                 assert(0);
  545         }
  546     }
  547 
  548     /* Setup shader depth output. */
  549     if (shader->code.writes_depth) {
  550         shader->fg_depth_src = R300_FG_DEPTH_SRC_SHADER;
  551         shader->us_out_w = R300_W_FMT_W24 | R300_W_SRC_US;
  552     } else {
  553         shader->fg_depth_src = R300_FG_DEPTH_SRC_SCAN;
  554         shader->us_out_w = R300_W_FMT_W0 | R300_W_SRC_US;
  555     }
  556 
  557     /* And, finally... */
  558     rc_destroy(&compiler.Base);
  559 
  560     /* Build the command buffer. */
  561     r300_emit_fs_code_to_buffer(r300, shader);
  562 }
  563 
  564 boolean r300_pick_fragment_shader(struct r300_context* r300)
  565 {
  566     struct r300_fragment_shader* fs = r300_fs(r300);
  567     struct r300_fragment_program_external_state state;
  568     struct r300_fragment_shader_code* ptr;
  569 
  570     memset(&state, 0, sizeof(state));
  571     get_external_state(r300, &state);
  572 
  573     if (!fs->first) {
  574         /* Build the fragment shader for the first time. */
  575         fs->first = fs->shader = CALLOC_STRUCT(r300_fragment_shader_code);
  576 
  577         memcpy(&fs->shader->compare_state, &state,
  578             sizeof(struct r300_fragment_program_external_state));
  579         r300_translate_fragment_shader(r300, fs->shader, fs->state.tokens);
  580         return TRUE;
  581 
  582     } else {
  583         /* Check if the currently-bound shader has been compiled
  584          * with the texture-compare state we need. */
  585         if (memcmp(&fs->shader->compare_state, &state, sizeof(state)) != 0) {
  586             /* Search for the right shader. */
  587             ptr = fs->first;
  588             while (ptr) {
  589                 if (memcmp(&ptr->compare_state, &state, sizeof(state)) == 0) {
  590                     if (fs->shader != ptr) {
  591                         fs->shader = ptr;
  592                         return TRUE;
  593                     }
  594                     /* The currently-bound one is OK. */
  595                     return FALSE;
  596                 }
  597                 ptr = ptr->next;
  598             }
  599 
  600             /* Not found, gotta compile a new one. */
  601             ptr = CALLOC_STRUCT(r300_fragment_shader_code);
  602             ptr->next = fs->first;
  603             fs->first = fs->shader = ptr;
  604 
  605             ptr->compare_state = state;
  606             r300_translate_fragment_shader(r300, ptr, fs->state.tokens);
  607             return TRUE;
  608         }
  609     }
  610 
  611     return FALSE;
  612 }