text: /**************************************************************************
   *
   * Copyright 2010 VMware, Inc.
   * All Rights Reserved.
   *
   * Permission is hereby granted, free of charge, to any person obtaining a
   * copy of this software and associated documentation files (the
   * "Software"), to deal in the Software without restriction, including
   * without limitation the rights to use, copy, modify, merge, publish,
   * distribute, sub license, and/or sell copies of the Software, and to
   * permit persons to whom the Software is furnished to do so, subject to
   * the following conditions:
   *
   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
   * FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. IN NO EVENT SHALL
   * THE COPYRIGHT HOLDERS, AUTHORS AND/OR ITS SUPPLIERS BE LIABLE FOR ANY CLAIM,
   * DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR
   * OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE
   * USE OR OTHER DEALINGS IN THE SOFTWARE.
   *
   * The above copyright notice and this permission notice (including the
   * next paragraph) shall be included in all copies or substantial portions
   * of the Software.
   *
   **************************************************************************/
  
  
  #include "util/u_memory.h"
  #include "util/u_math.h"
  #include "tgsi/tgsi_parse.h"
  #include "tgsi/tgsi_util.h"
  #include "tgsi/tgsi_dump.h"
  #include "tgsi/tgsi_strings.h"
  #include "lp_bld_debug.h"
  #include "lp_bld_tgsi.h"
  
  
  /**
   * Analysis context.
   *
   * This is where we keep store the value of each channel of the IMM/TEMP/OUT
   * register values, as we walk the shader.
   */
  struct analysis_context
  {
     struct lp_tgsi_info *info;
  
     unsigned num_imms;
     float imm[LP_MAX_TGSI_IMMEDIATES][4];
     unsigned sample_target[PIPE_MAX_SHADER_SAMPLER_VIEWS];
  
     struct lp_tgsi_channel_info temp[32][4];
  };
  
  
  /**
   * Describe the specified channel of the src register.
   */
  static void
  analyse_src(struct analysis_context *ctx,
              struct lp_tgsi_channel_info *chan_info,
              const struct tgsi_src_register *src,
              unsigned chan)
  {
     chan_info->file = TGSI_FILE_NULL;
     if (!src->Indirect && !src->Absolute && !src->Negate) {
        unsigned swizzle = tgsi_util_get_src_register_swizzle(src, chan);
        if (src->File == TGSI_FILE_TEMPORARY) {
           if (src->Index < ARRAY_SIZE(ctx->temp)) {
              *chan_info = ctx->temp[src->Index][swizzle];
           }
        } else {
           chan_info->file = src->File;
           if (src->File == TGSI_FILE_IMMEDIATE) {
              assert(src->Index < ARRAY_SIZE(ctx->imm));
              if (src->Index < ARRAY_SIZE(ctx->imm)) {
                 chan_info->u.value = ctx->imm[src->Index][swizzle];
              }
           } else {
              chan_info->u.index = src->Index;
              chan_info->swizzle = swizzle;
           }
        }
     }
  }
  
  
  /**
   * Whether this register channel refers to a specific immediate value.
   */
  static boolean
  is_immediate(const struct lp_tgsi_channel_info *chan_info, float value)
  {
     return chan_info->file == TGSI_FILE_IMMEDIATE &&
            chan_info->u.value == value;
  }
  
  
  /**
   * Analyse properties of tex instructions, in particular used
   * to figure out if a texture is considered indirect.
   * Not actually used by much except the tgsi dumping code.
   */
  static void
  analyse_tex(struct analysis_context *ctx,
              const struct tgsi_full_instruction *inst,
              enum lp_build_tex_modifier modifier)
  {
     struct lp_tgsi_info *info = ctx->info;
     unsigned chan;
  
     if (info->num_texs < ARRAY_SIZE(info->tex)) {
        struct lp_tgsi_texture_info *tex_info = &info->tex[info->num_texs];
        boolean indirect = FALSE;
        unsigned readmask = 0;
  
        tex_info->target = inst->Texture.Texture;
        switch (inst->Texture.Texture) {
        case TGSI_TEXTURE_1D:
           readmask = TGSI_WRITEMASK_X;
           break;
        case TGSI_TEXTURE_1D_ARRAY:
        case TGSI_TEXTURE_2D:
        case TGSI_TEXTURE_RECT:
           readmask = TGSI_WRITEMASK_XY;
           break;
        case TGSI_TEXTURE_SHADOW1D:
        case TGSI_TEXTURE_SHADOW1D_ARRAY:
        case TGSI_TEXTURE_SHADOW2D:
        case TGSI_TEXTURE_SHADOWRECT:
        case TGSI_TEXTURE_2D_ARRAY:
        case TGSI_TEXTURE_2D_MSAA:
        case TGSI_TEXTURE_3D:
        case TGSI_TEXTURE_CUBE:
           readmask = TGSI_WRITEMASK_XYZ;
           break;
        case TGSI_TEXTURE_SHADOW2D_ARRAY:
        case TGSI_TEXTURE_SHADOWCUBE:
        case TGSI_TEXTURE_2D_ARRAY_MSAA:
        case TGSI_TEXTURE_CUBE_ARRAY:
           readmask = TGSI_WRITEMASK_XYZW;
           /* modifier would be in another not analyzed reg so just say indirect */
           if (modifier != LP_BLD_TEX_MODIFIER_NONE) {
              indirect = TRUE;
           }
           break;
        case TGSI_TEXTURE_SHADOWCUBE_ARRAY:
           readmask = TGSI_WRITEMASK_XYZW;
           indirect = TRUE;
           break;
        default:
           assert(0);
           return;
        }
  
        if (modifier == LP_BLD_TEX_MODIFIER_EXPLICIT_DERIV) {
           /* We don't track explicit derivatives, although we could */
           indirect = TRUE;
           tex_info->sampler_unit = inst->Src[3].Register.Index;
           tex_info->texture_unit = inst->Src[3].Register.Index;
        }  else {
           if (modifier == LP_BLD_TEX_MODIFIER_PROJECTED ||
               modifier == LP_BLD_TEX_MODIFIER_LOD_BIAS ||
               modifier == LP_BLD_TEX_MODIFIER_EXPLICIT_LOD) {
              readmask |= TGSI_WRITEMASK_W;
           }
           tex_info->sampler_unit = inst->Src[1].Register.Index;
           tex_info->texture_unit = inst->Src[1].Register.Index;
        }
  
        for (chan = 0; chan < 4; ++chan) {
           struct lp_tgsi_channel_info *chan_info = &tex_info->coord[chan];
           if (readmask & (1 << chan)) {
              analyse_src(ctx, chan_info, &inst->Src[0].Register, chan);
              if (chan_info->file != TGSI_FILE_INPUT) {
                 indirect = TRUE;
              }
           } else {
              memset(chan_info, 0, sizeof *chan_info);
           }
        }
  
        if (indirect) {
           info->indirect_textures = TRUE;
        }
  
        ++info->num_texs;
     } else {
        info->indirect_textures = TRUE;
     }
  }
  
  
  /**
   * Analyse properties of sample instructions, in particular used
   * to figure out if a texture is considered indirect.
   * Not actually used by much except the tgsi dumping code.
   */
  static void
  analyse_sample(struct analysis_context *ctx,
                 const struct tgsi_full_instruction *inst,
                 enum lp_build_tex_modifier modifier,
                 boolean shadow)
  {
     struct lp_tgsi_info *info = ctx->info;
     unsigned chan;
  
     if (info->num_texs < ARRAY_SIZE(info->tex)) {
        struct lp_tgsi_texture_info *tex_info = &info->tex[info->num_texs];
        unsigned target = ctx->sample_target[inst->Src[1].Register.Index];
        boolean indirect = FALSE;
        boolean shadow = FALSE;
        unsigned readmask;
  
        switch (target) {
        /* note no shadow targets here */
        case TGSI_TEXTURE_BUFFER:
        case TGSI_TEXTURE_1D:
           readmask = TGSI_WRITEMASK_X;
           break;
        case TGSI_TEXTURE_1D_ARRAY:
        case TGSI_TEXTURE_2D:
        case TGSI_TEXTURE_RECT:
           readmask = TGSI_WRITEMASK_XY;
           break;
        case TGSI_TEXTURE_2D_ARRAY:
        case TGSI_TEXTURE_2D_MSAA:
        case TGSI_TEXTURE_3D:
        case TGSI_TEXTURE_CUBE:
           readmask = TGSI_WRITEMASK_XYZ;
           break;
        case TGSI_TEXTURE_CUBE_ARRAY:
        case TGSI_TEXTURE_2D_ARRAY_MSAA:
           readmask = TGSI_WRITEMASK_XYZW;
           break;
        default:
           assert(0);
           return;
        }
  
        tex_info->target = target;
        tex_info->texture_unit = inst->Src[1].Register.Index;
        tex_info->sampler_unit = inst->Src[2].Register.Index;
  
        if (tex_info->texture_unit != tex_info->sampler_unit) {
           info->sampler_texture_units_different = TRUE;
        }
  
        if (modifier == LP_BLD_TEX_MODIFIER_EXPLICIT_DERIV ||
            modifier == LP_BLD_TEX_MODIFIER_EXPLICIT_LOD ||
            modifier == LP_BLD_TEX_MODIFIER_LOD_BIAS || shadow) {
           /* We don't track insts with additional regs, although we could */
           indirect = TRUE;
        }
  
        for (chan = 0; chan < 4; ++chan) {
           struct lp_tgsi_channel_info *chan_info = &tex_info->coord[chan];
           if (readmask & (1 << chan)) {
              analyse_src(ctx, chan_info, &inst->Src[0].Register, chan);
              if (chan_info->file != TGSI_FILE_INPUT) {
                 indirect = TRUE;
              }
           } else {
              memset(chan_info, 0, sizeof *chan_info);
           }
        }
  
        if (indirect) {
           info->indirect_textures = TRUE;
        }
  
        ++info->num_texs;
     } else {
        info->indirect_textures = TRUE;
     }
  }
  
  
  /**
   * Process an instruction, and update the register values accordingly.
   */
  static void
  analyse_instruction(struct analysis_context *ctx,
                      struct tgsi_full_instruction *inst)
  {
     struct lp_tgsi_info *info = ctx->info;
     struct lp_tgsi_channel_info (*regs)[4];
     unsigned max_regs;
     unsigned i;
     unsigned index;
     unsigned chan;
  
     for (i = 0; i < inst->Instruction.NumDstRegs; ++i) {
        const struct tgsi_dst_register *dst = &inst->Dst[i].Register;
  
        /*
         * Get the lp_tgsi_channel_info array corresponding to the destination
         * register file.
         */
  
        if (dst->File == TGSI_FILE_TEMPORARY) {
           regs = ctx->temp;
           max_regs = ARRAY_SIZE(ctx->temp);
        } else if (dst->File == TGSI_FILE_OUTPUT) {
           regs = info->output;
           max_regs = ARRAY_SIZE(info->output);
        } else if (dst->File == TGSI_FILE_ADDRESS) {
           continue;
        } else {
           assert(0);
           continue;
        }
  
        /*
         * Detect direct TEX instructions
         */
  
        switch (inst->Instruction.Opcode) {
        case TGSI_OPCODE_TEX:
           analyse_tex(ctx, inst, LP_BLD_TEX_MODIFIER_NONE);
           break;
        case TGSI_OPCODE_TXD:
           analyse_tex(ctx, inst, LP_BLD_TEX_MODIFIER_EXPLICIT_DERIV);
           break;
        case TGSI_OPCODE_TXB:
           analyse_tex(ctx, inst, LP_BLD_TEX_MODIFIER_LOD_BIAS);
           break;
        case TGSI_OPCODE_TXL:
           analyse_tex(ctx, inst, LP_BLD_TEX_MODIFIER_EXPLICIT_LOD);
           break;
        case TGSI_OPCODE_TXP:
           analyse_tex(ctx, inst, LP_BLD_TEX_MODIFIER_PROJECTED);
           break;
        case TGSI_OPCODE_TEX2:
           analyse_tex(ctx, inst, LP_BLD_TEX_MODIFIER_NONE);
           break;
        case TGSI_OPCODE_TXB2:
           analyse_tex(ctx, inst, LP_BLD_TEX_MODIFIER_LOD_BIAS);
           break;
        case TGSI_OPCODE_TXL2:
           analyse_tex(ctx, inst, LP_BLD_TEX_MODIFIER_EXPLICIT_LOD);
           break;
        case TGSI_OPCODE_SAMPLE:
           analyse_sample(ctx, inst, LP_BLD_TEX_MODIFIER_NONE, FALSE);
           break;
        case TGSI_OPCODE_SAMPLE_C:
           analyse_sample(ctx, inst, LP_BLD_TEX_MODIFIER_NONE, TRUE);
           break;
        case TGSI_OPCODE_SAMPLE_C_LZ:
           analyse_sample(ctx, inst, LP_BLD_TEX_MODIFIER_LOD_ZERO, TRUE);
           break;
        case TGSI_OPCODE_SAMPLE_D:
           analyse_sample(ctx, inst, LP_BLD_TEX_MODIFIER_EXPLICIT_DERIV, FALSE);
           break;
        case TGSI_OPCODE_SAMPLE_B:
           analyse_sample(ctx, inst, LP_BLD_TEX_MODIFIER_LOD_BIAS, FALSE);
           break;
        case TGSI_OPCODE_SAMPLE_L:
           analyse_sample(ctx, inst, LP_BLD_TEX_MODIFIER_EXPLICIT_LOD, FALSE);
           break;
        default:
           break;
        }
  
        /*
         * Keep track of assignments and writes
         */
  
        if (dst->Indirect) {
           /*
            * It could be any register index so clear all register indices.
            */
  
           for (chan = 0; chan < 4; ++chan) {
              if (dst->WriteMask & (1 << chan)) {
                 for (index = 0; index < max_regs; ++index) {
                    regs[index][chan].file = TGSI_FILE_NULL;
                 }
              }
           }
        } else if (dst->Index < max_regs) {
           /*
            * Update this destination register value.
            */
  
           struct lp_tgsi_channel_info res[4];
  
           memset(res, 0, sizeof res);
  
           if (!inst->Instruction.Saturate) {
              for (chan = 0; chan < 4; ++chan) {
                 if (dst->WriteMask & (1 << chan)) {
                    if (inst->Instruction.Opcode == TGSI_OPCODE_MOV) {
                       analyse_src(ctx, &res[chan],
                                   &inst->Src[0].Register, chan);
                    } else if (inst->Instruction.Opcode == TGSI_OPCODE_MUL) {
                       /*
                        * Propagate values across 1.0 and 0.0 multiplications.
                        */
  
                       struct lp_tgsi_channel_info src0;
                       struct lp_tgsi_channel_info src1;
  
                       analyse_src(ctx, &src0, &inst->Src[0].Register, chan);
                       analyse_src(ctx, &src1, &inst->Src[1].Register, chan);
  
                       if (is_immediate(&src0, 0.0f)) {
                          res[chan] = src0;
                       } else if (is_immediate(&src1, 0.0f)) {
                          res[chan] = src1;
                       } else if (is_immediate(&src0, 1.0f)) {
                          res[chan] = src1;
                       } else if (is_immediate(&src1, 1.0f)) {
                          res[chan] = src0;
                       }
                    }
                 }
              }
           }
  
           for (chan = 0; chan < 4; ++chan) {
              if (dst->WriteMask & (1 << chan)) {
                 regs[dst->Index][chan] = res[chan];
              }
           }
        }
     }
  
     /*
      * Clear all temporaries information in presence of a control flow opcode.
      */
  
     switch (inst->Instruction.Opcode) {
     case TGSI_OPCODE_IF:
     case TGSI_OPCODE_UIF:
     case TGSI_OPCODE_ELSE:
     case TGSI_OPCODE_ENDIF:
     case TGSI_OPCODE_BGNLOOP:
     case TGSI_OPCODE_BRK:
     case TGSI_OPCODE_CONT:
     case TGSI_OPCODE_ENDLOOP:
     case TGSI_OPCODE_CAL:
     case TGSI_OPCODE_BGNSUB:
     case TGSI_OPCODE_ENDSUB:
     case TGSI_OPCODE_SWITCH:
     case TGSI_OPCODE_CASE:
     case TGSI_OPCODE_DEFAULT:
     case TGSI_OPCODE_ENDSWITCH:
     case TGSI_OPCODE_RET:
     case TGSI_OPCODE_END:
        /* XXX: Are there more cases? */
        memset(&ctx->temp, 0, sizeof ctx->temp);
        memset(&info->output, 0, sizeof info->output);
     default:
        break;
     }
  }
  
  
  static inline void
  dump_info(const struct tgsi_token *tokens,
            struct lp_tgsi_info *info)
  {
     unsigned index;
     unsigned chan;
  
     tgsi_dump(tokens, 0);
  
     for (index = 0; index < info->num_texs; ++index) {
        const struct lp_tgsi_texture_info *tex_info = &info->tex[index];
        debug_printf("TEX[%u] =", index);
        for (chan = 0; chan < 4; ++chan) {
           const struct lp_tgsi_channel_info *chan_info =
                 &tex_info->coord[chan];
           if (chan_info->file != TGSI_FILE_NULL) {
              debug_printf(" %s[%u].%c",
                           tgsi_file_name(chan_info->file),
                           chan_info->u.index,
                           "xyzw01"[chan_info->swizzle]);
           } else {
              debug_printf(" _");
           }
        }
        debug_printf(", RES[%u], SAMP[%u], %s\n",
                     tex_info->texture_unit,
                     tex_info->sampler_unit,
                     tgsi_texture_names[tex_info->target]);
     }
  
     for (index = 0; index < PIPE_MAX_SHADER_OUTPUTS; ++index) {
        for (chan = 0; chan < 4; ++chan) {
           const struct lp_tgsi_channel_info *chan_info =
                 &info->output[index][chan];
           if (chan_info->file != TGSI_FILE_NULL) {
              debug_printf("OUT[%u].%c = ", index, "xyzw"[chan]);
              if (chan_info->file == TGSI_FILE_IMMEDIATE) {
                 debug_printf("%f", chan_info->u.value);
              } else {
                 const char *file_name;
                 switch (chan_info->file) {
                 case TGSI_FILE_CONSTANT:
                    file_name = "CONST";
                    break;
                 case TGSI_FILE_INPUT:
                    file_name = "IN";
                    break;
                 default:
                    file_name = "???";
                    break;
                 }
                 debug_printf("%s[%u].%c",
                              file_name,
                              chan_info->u.index,
                              "xyzw01"[chan_info->swizzle]);
              }
              debug_printf("\n");
           }
        }
     }
  }
  
  
  /**
   * Detect any direct relationship between the output color
   */
  void
  lp_build_tgsi_info(const struct tgsi_token *tokens,
                     struct lp_tgsi_info *info)
  {
     struct tgsi_parse_context parse;
     struct analysis_context *ctx;
     unsigned index;
     unsigned chan;
  
     memset(info, 0, sizeof *info);
  
     tgsi_scan_shader(tokens, &info->base);
  
     ctx = CALLOC(1, sizeof(struct analysis_context));
     ctx->info = info;
  
     tgsi_parse_init(&parse, tokens);
  
     while (!tgsi_parse_end_of_tokens(&parse)) {
        tgsi_parse_token(&parse);
  
        switch (parse.FullToken.Token.Type) {
        case TGSI_TOKEN_TYPE_DECLARATION: {
           struct tgsi_full_declaration *decl = &parse.FullToken.FullDeclaration;
           if (decl->Declaration.File == TGSI_FILE_SAMPLER_VIEW) {
              for (index = decl->Range.First; index <= decl->Range.Last; index++) {
                 ctx->sample_target[index] = decl->SamplerView.Resource;
              }
           }
        }
           break;
  
        case TGSI_TOKEN_TYPE_INSTRUCTION:
           {
              struct tgsi_full_instruction *inst =
                    &parse.FullToken.FullInstruction;
  
              if (inst->Instruction.Opcode == TGSI_OPCODE_END ||
                  inst->Instruction.Opcode == TGSI_OPCODE_BGNSUB) {
                 /* We reached the end of main function body. */
                 goto finished;
              }
  
              analyse_instruction(ctx, inst);
           }
           break;
  
        case TGSI_TOKEN_TYPE_IMMEDIATE:
           {
              const unsigned size =
                    parse.FullToken.FullImmediate.Immediate.NrTokens - 1;
              assert(size <= 4);
              if (ctx->num_imms < ARRAY_SIZE(ctx->imm)) {
                 for (chan = 0; chan < size; ++chan) {
                    float value = parse.FullToken.FullImmediate.u[chan].Float;
                    ctx->imm[ctx->num_imms][chan] = value;
  
                    if (value < 0.0f || value > 1.0f) {
                       info->unclamped_immediates = TRUE;
                    }
                 }
                 ++ctx->num_imms;
              }
           }
           break;
  
        case TGSI_TOKEN_TYPE_PROPERTY:
           break;
  
        default:
           assert(0);
        }
     }
  finished:
  
     tgsi_parse_free(&parse);
     FREE(ctx);
  
  
     /*
      * Link the output color values.
      */
  
     for (index = 0; index < PIPE_MAX_COLOR_BUFS; ++index) {
        const struct lp_tgsi_channel_info null_output[4];
        info->cbuf[index] = null_output;
     }
  
     for (index = 0; index < info->base.num_outputs; ++index) {
        unsigned semantic_name = info->base.output_semantic_name[index];
        unsigned semantic_index = info->base.output_semantic_index[index];
        if (semantic_name == TGSI_SEMANTIC_COLOR &&
            semantic_index < PIPE_MAX_COLOR_BUFS) {
           info->cbuf[semantic_index] = info->output[index];
        }
     }
  
     if (gallivm_debug & GALLIVM_DEBUG_TGSI) {
        dump_info(tokens, info);
     }
  }
  