drivers/llvmpipe/lp_tex_sample.c

/**************************************************************************
 *
 * Copyright 2009 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 above copyright notice and this permission notice (including the
 * next paragraph) shall be included in all copies or substantial portions
 * of the Software.
 *
 * 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 VMWARE 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.
 *
 **************************************************************************/

/**
 * Texture sampling code generation
 *
 * This file is nothing more than ugly glue between three largely independent
 * entities:
 * - TGSI -> LLVM translation (i.e., lp_build_tgsi_soa)
 * - texture sampling code generation (i.e., lp_build_sample_soa)
 * - LLVM pipe driver
 *
 * All interesting code is in the functions mentioned above. There is really
 * nothing to see here.
 *
 * @author Jose Fonseca <jfonseca@vmware.com>
 */

#include "pipe/p_defines.h"
#include "pipe/p_shader_tokens.h"
#include "gallivm/lp_bld_debug.h"
#include "gallivm/lp_bld_const.h"
#include "gallivm/lp_bld_type.h"
#include "gallivm/lp_bld_sample.h"
#include "gallivm/lp_bld_tgsi.h"
#include "lp_jit.h"
#include "lp_tex_sample.h"
#include "lp_state_fs.h"
#include "lp_debug.h"


/**
 * This provides the bridge between the sampler state store in
 * lp_jit_context and lp_jit_texture and the sampler code
 * generator. It provides the texture layout information required by
 * the texture sampler code generator in terms of the state stored in
 * lp_jit_context and lp_jit_texture in runtime.
 */
struct llvmpipe_sampler_dynamic_state
{
   struct lp_sampler_dynamic_state base;

   const struct lp_sampler_static_state *static_state;
};


/**
 * This is the bridge between our sampler and the TGSI translator.
 */
struct lp_llvm_sampler_soa
{
   struct lp_build_sampler_soa base;

   struct llvmpipe_sampler_dynamic_state dynamic_state;
   unsigned nr_samplers;
};


struct llvmpipe_image_dynamic_state
{
   struct lp_sampler_dynamic_state base;

   const struct lp_image_static_state *static_state;
};


/**
 * This is the bridge between our images and the TGSI translator.
 */
struct lp_llvm_image_soa
{
   struct lp_build_image_soa base;

   struct llvmpipe_image_dynamic_state dynamic_state;
   unsigned nr_images;
};


/**
 * Fetch the specified member of the lp_jit_texture structure.
 * \param emit_load  if TRUE, emit the LLVM load instruction to actually
 *                   fetch the field's value.  Otherwise, just emit the
 *                   GEP code to address the field.
 *
 * @sa http://llvm.org/docs/GetElementPtr.html
 */
static LLVMValueRef
lp_llvm_texture_member(const struct lp_sampler_dynamic_state *base,
                       struct gallivm_state *gallivm,
                       LLVMValueRef context_ptr,
                       unsigned texture_unit,
                       LLVMValueRef texture_unit_offset,
                       unsigned member_index,
                       const char *member_name,
                       boolean emit_load)
{
   LLVMBuilderRef builder = gallivm->builder;
   LLVMValueRef indices[4];

   assert(texture_unit < PIPE_MAX_SHADER_SAMPLER_VIEWS);

   /* context[0] */
   indices[0] = lp_build_const_int32(gallivm, 0);
   /* context[0].textures */
   indices[1] = lp_build_const_int32(gallivm, LP_JIT_CTX_TEXTURES);
   /* context[0].textures[unit] */
   indices[2] = lp_build_const_int32(gallivm, texture_unit);
   if (texture_unit_offset) {
      indices[2] = LLVMBuildAdd(gallivm->builder, indices[2],
                                texture_unit_offset, "");
      LLVMValueRef cond =
         LLVMBuildICmp(gallivm->builder, LLVMIntULT,
                       indices[2],
                       lp_build_const_int32(gallivm,
                                            PIPE_MAX_SHADER_SAMPLER_VIEWS), "");
      indices[2] = LLVMBuildSelect(gallivm->builder, cond, indices[2],
                                   lp_build_const_int32(gallivm,
                                                        texture_unit), "");
   }
   /* context[0].textures[unit].member */
   indices[3] = lp_build_const_int32(gallivm, member_index);

   LLVMValueRef ptr =
      LLVMBuildGEP(builder, context_ptr, indices, ARRAY_SIZE(indices), "");

   LLVMValueRef res = emit_load ? LLVMBuildLoad(builder, ptr, "") : ptr;

   lp_build_name(res, "context.texture%u.%s", texture_unit, member_name);

   return res;
}


/**
 * Helper macro to instantiate the functions that generate the code to
 * fetch the members of lp_jit_texture to fulfill the sampler code
 * generator requests.
 *
 * This complexity is the price we have to pay to keep the texture
 * sampler code generator a reusable module without dependencies to
 * llvmpipe internals.
 */
#define LP_LLVM_TEXTURE_MEMBER(_name, _index, _emit_load)  \
   static LLVMValueRef \
   lp_llvm_texture_##_name( const struct lp_sampler_dynamic_state *base, \
                            struct gallivm_state *gallivm, \
                            LLVMValueRef context_ptr, \
                            unsigned texture_unit,    \
                            LLVMValueRef texture_unit_offset) \
   { \
      return lp_llvm_texture_member(base, gallivm, context_ptr, \
                                    texture_unit, texture_unit_offset,  \
                                    _index, #_name, _emit_load );       \
   }


LP_LLVM_TEXTURE_MEMBER(width,      LP_JIT_TEXTURE_WIDTH, TRUE)
LP_LLVM_TEXTURE_MEMBER(height,     LP_JIT_TEXTURE_HEIGHT, TRUE)
LP_LLVM_TEXTURE_MEMBER(depth,      LP_JIT_TEXTURE_DEPTH, TRUE)
LP_LLVM_TEXTURE_MEMBER(first_level, LP_JIT_TEXTURE_FIRST_LEVEL, TRUE)
LP_LLVM_TEXTURE_MEMBER(last_level, LP_JIT_TEXTURE_LAST_LEVEL, TRUE)
LP_LLVM_TEXTURE_MEMBER(base_ptr,   LP_JIT_TEXTURE_BASE, TRUE)
LP_LLVM_TEXTURE_MEMBER(row_stride, LP_JIT_TEXTURE_ROW_STRIDE, FALSE)
LP_LLVM_TEXTURE_MEMBER(img_stride, LP_JIT_TEXTURE_IMG_STRIDE, FALSE)
LP_LLVM_TEXTURE_MEMBER(mip_offsets, LP_JIT_TEXTURE_MIP_OFFSETS, FALSE)
LP_LLVM_TEXTURE_MEMBER(num_samples, LP_JIT_TEXTURE_NUM_SAMPLES, TRUE)
LP_LLVM_TEXTURE_MEMBER(sample_stride, LP_JIT_TEXTURE_SAMPLE_STRIDE, TRUE)


/**
 * Fetch the specified member of the lp_jit_sampler structure.
 * \param emit_load  if TRUE, emit the LLVM load instruction to actually
 *                   fetch the field's value.  Otherwise, just emit the
 *                   GEP code to address the field.
 *
 * @sa http://llvm.org/docs/GetElementPtr.html
 */
static LLVMValueRef
lp_llvm_sampler_member(const struct lp_sampler_dynamic_state *base,
                       struct gallivm_state *gallivm,
                       LLVMValueRef context_ptr,
                       unsigned sampler_unit,
                       unsigned member_index,
                       const char *member_name,
                       boolean emit_load)
{
   LLVMBuilderRef builder = gallivm->builder;
   LLVMValueRef indices[4];

   assert(sampler_unit < PIPE_MAX_SAMPLERS);

   /* context[0] */
   indices[0] = lp_build_const_int32(gallivm, 0);
   /* context[0].samplers */
   indices[1] = lp_build_const_int32(gallivm, LP_JIT_CTX_SAMPLERS);
   /* context[0].samplers[unit] */
   indices[2] = lp_build_const_int32(gallivm, sampler_unit);
   /* context[0].samplers[unit].member */
   indices[3] = lp_build_const_int32(gallivm, member_index);

   LLVMValueRef ptr =
      LLVMBuildGEP(builder, context_ptr, indices, ARRAY_SIZE(indices), "");

   LLVMValueRef res = emit_load ? LLVMBuildLoad(builder, ptr, "") : ptr;

   lp_build_name(res, "context.sampler%u.%s", sampler_unit, member_name);

   return res;
}


#define LP_LLVM_SAMPLER_MEMBER(_name, _index, _emit_load)  \
   static LLVMValueRef \
   lp_llvm_sampler_##_name( const struct lp_sampler_dynamic_state *base, \
                            struct gallivm_state *gallivm, \
                            LLVMValueRef context_ptr, \
                            unsigned sampler_unit) \
   { \
      return lp_llvm_sampler_member(base, gallivm, context_ptr, \
                                    sampler_unit, _index, #_name, _emit_load ); \
   }


LP_LLVM_SAMPLER_MEMBER(min_lod,    LP_JIT_SAMPLER_MIN_LOD, TRUE)
LP_LLVM_SAMPLER_MEMBER(max_lod,    LP_JIT_SAMPLER_MAX_LOD, TRUE)
LP_LLVM_SAMPLER_MEMBER(lod_bias,   LP_JIT_SAMPLER_LOD_BIAS, TRUE)
LP_LLVM_SAMPLER_MEMBER(border_color, LP_JIT_SAMPLER_BORDER_COLOR, FALSE)
LP_LLVM_SAMPLER_MEMBER(max_aniso, LP_JIT_SAMPLER_MAX_ANISO, TRUE)


/**
 * Fetch the specified member of the lp_jit_image structure.
 * \param emit_load  if TRUE, emit the LLVM load instruction to actually
 *                   fetch the field's value.  Otherwise, just emit the
 *                   GEP code to address the field.
 *
 * @sa http://llvm.org/docs/GetElementPtr.html
 */
static LLVMValueRef
lp_llvm_image_member(const struct lp_sampler_dynamic_state *base,
                     struct gallivm_state *gallivm,
                     LLVMValueRef context_ptr,
                     unsigned image_unit,
                     LLVMValueRef image_unit_offset,
                     unsigned member_index,
                     const char *member_name,
                     boolean emit_load)
{
   LLVMBuilderRef builder = gallivm->builder;
   LLVMValueRef indices[4];

   assert(image_unit < PIPE_MAX_SHADER_IMAGES);

   /* context[0] */
   indices[0] = lp_build_const_int32(gallivm, 0);
   /* context[0].images */
   indices[1] = lp_build_const_int32(gallivm, LP_JIT_CTX_IMAGES);
   /* context[0].images[unit] */
   indices[2] = lp_build_const_int32(gallivm, image_unit);
   if (image_unit_offset) {
      indices[2] = LLVMBuildAdd(gallivm->builder, indices[2], image_unit_offset, "");
      LLVMValueRef cond = LLVMBuildICmp(gallivm->builder, LLVMIntULT, indices[2], lp_build_const_int32(gallivm, PIPE_MAX_SHADER_IMAGES), "");
      indices[2] = LLVMBuildSelect(gallivm->builder, cond, indices[2], lp_build_const_int32(gallivm, image_unit), "");
   }
   /* context[0].images[unit].member */
   indices[3] = lp_build_const_int32(gallivm, member_index);

   LLVMValueRef ptr =
      LLVMBuildGEP(builder, context_ptr, indices, ARRAY_SIZE(indices), "");

   LLVMValueRef res = emit_load ? LLVMBuildLoad(builder, ptr, "") : ptr;

   lp_build_name(res, "context.image%u.%s", image_unit, member_name);

   return res;
}


/**
 * Helper macro to instantiate the functions that generate the code to
 * fetch the members of lp_jit_image to fulfill the sampler code
 * generator requests.
 *
 * This complexity is the price we have to pay to keep the image
 * sampler code generator a reusable module without dependencies to
 * llvmpipe internals.
 */
#define LP_LLVM_IMAGE_MEMBER(_name, _index, _emit_load)  \
   static LLVMValueRef \
   lp_llvm_image_##_name( const struct lp_sampler_dynamic_state *base, \
                          struct gallivm_state *gallivm,               \
                          LLVMValueRef context_ptr,                     \
                          unsigned image_unit, LLVMValueRef image_unit_offset) \
   { \
      return lp_llvm_image_member(base, gallivm, context_ptr, \
                                  image_unit, image_unit_offset, \
                                  _index, #_name, _emit_load );  \
   }


LP_LLVM_IMAGE_MEMBER(width,      LP_JIT_IMAGE_WIDTH, TRUE)
LP_LLVM_IMAGE_MEMBER(height,     LP_JIT_IMAGE_HEIGHT, TRUE)
LP_LLVM_IMAGE_MEMBER(depth,      LP_JIT_IMAGE_DEPTH, TRUE)
LP_LLVM_IMAGE_MEMBER(base_ptr,   LP_JIT_IMAGE_BASE, TRUE)
LP_LLVM_IMAGE_MEMBER(row_stride, LP_JIT_IMAGE_ROW_STRIDE, TRUE)
LP_LLVM_IMAGE_MEMBER(img_stride, LP_JIT_IMAGE_IMG_STRIDE, TRUE)
LP_LLVM_IMAGE_MEMBER(num_samples, LP_JIT_IMAGE_NUM_SAMPLES, TRUE)
LP_LLVM_IMAGE_MEMBER(sample_stride, LP_JIT_IMAGE_SAMPLE_STRIDE, TRUE)


#if LP_USE_TEXTURE_CACHE
static LLVMValueRef
lp_llvm_texture_cache_ptr(const struct lp_sampler_dynamic_state *base,
                          struct gallivm_state *gallivm,
                          LLVMValueRef thread_data_ptr,
                          unsigned unit)
{
   /* We use the same cache for all units */
   (void)unit;

   return lp_jit_thread_data_cache(gallivm, thread_data_ptr);
}
#endif


static void
lp_llvm_sampler_soa_destroy(struct lp_build_sampler_soa *sampler)
{
   FREE(sampler);
}


/**
 * Fetch filtered values from texture.
 * The 'texel' parameter returns four vectors corresponding to R, G, B, A.
 */
static void
lp_llvm_sampler_soa_emit_fetch_texel(const struct lp_build_sampler_soa *base,
                                     struct gallivm_state *gallivm,
                                     const struct lp_sampler_params *params)
{
   struct lp_llvm_sampler_soa *sampler = (struct lp_llvm_sampler_soa *)base;
   const unsigned texture_index = params->texture_index;
   const unsigned sampler_index = params->sampler_index;

   assert(sampler_index < PIPE_MAX_SAMPLERS);
   assert(texture_index < PIPE_MAX_SHADER_SAMPLER_VIEWS);

   if (LP_PERF & PERF_NO_TEX) {
      lp_build_sample_nop(gallivm, params->type, params->coords, params->texel);
      return;
   }

   if (params->texture_index_offset) {
      LLVMValueRef unit =
         LLVMBuildAdd(gallivm->builder, params->texture_index_offset,
                      lp_build_const_int32(gallivm, texture_index), "");

      struct lp_build_sample_array_switch switch_info;
      memset(&switch_info, 0, sizeof(switch_info));
      lp_build_sample_array_init_soa(&switch_info, gallivm, params, unit,
                                     0, sampler->nr_samplers);
      // build the switch cases
      for (unsigned i = 0; i < sampler->nr_samplers; i++) {
         lp_build_sample_array_case_soa(&switch_info, i,
                                        &sampler->dynamic_state.static_state[i].texture_state,
                                        &sampler->dynamic_state.static_state[i].sampler_state,
                                        &sampler->dynamic_state.base);
      }
      lp_build_sample_array_fini_soa(&switch_info);
   } else {
      lp_build_sample_soa(&sampler->dynamic_state.static_state[texture_index].texture_state,
                          &sampler->dynamic_state.static_state[sampler_index].sampler_state,
                          &sampler->dynamic_state.base,
                          gallivm, params);
   }
}


/**
 * Fetch the texture size.
 */
static void
lp_llvm_sampler_soa_emit_size_query(const struct lp_build_sampler_soa *base,
                                    struct gallivm_state *gallivm,
                                    const struct lp_sampler_size_query_params *params)
{
   struct lp_llvm_sampler_soa *sampler = (struct lp_llvm_sampler_soa *)base;

   assert(params->texture_unit < PIPE_MAX_SHADER_SAMPLER_VIEWS);

   lp_build_size_query_soa(gallivm,
                           &sampler->dynamic_state.static_state[params->texture_unit].texture_state,
                           &sampler->dynamic_state.base,
                           params);
}


struct lp_build_sampler_soa *
lp_llvm_sampler_soa_create(const struct lp_sampler_static_state *static_state,
                           unsigned nr_samplers)
{
   assert(static_state);

   struct lp_llvm_sampler_soa *sampler = CALLOC_STRUCT(lp_llvm_sampler_soa);
   if (!sampler)
      return NULL;

   sampler->base.destroy = lp_llvm_sampler_soa_destroy;
   sampler->base.emit_tex_sample = lp_llvm_sampler_soa_emit_fetch_texel;
   sampler->base.emit_size_query = lp_llvm_sampler_soa_emit_size_query;
   sampler->dynamic_state.base.width = lp_llvm_texture_width;
   sampler->dynamic_state.base.height = lp_llvm_texture_height;
   sampler->dynamic_state.base.depth = lp_llvm_texture_depth;
   sampler->dynamic_state.base.first_level = lp_llvm_texture_first_level;
   sampler->dynamic_state.base.last_level = lp_llvm_texture_last_level;
   sampler->dynamic_state.base.base_ptr = lp_llvm_texture_base_ptr;
   sampler->dynamic_state.base.row_stride = lp_llvm_texture_row_stride;
   sampler->dynamic_state.base.img_stride = lp_llvm_texture_img_stride;
   sampler->dynamic_state.base.mip_offsets = lp_llvm_texture_mip_offsets;
   sampler->dynamic_state.base.num_samples = lp_llvm_texture_num_samples;
   sampler->dynamic_state.base.sample_stride = lp_llvm_texture_sample_stride;
   sampler->dynamic_state.base.min_lod = lp_llvm_sampler_min_lod;
   sampler->dynamic_state.base.max_lod = lp_llvm_sampler_max_lod;
   sampler->dynamic_state.base.lod_bias = lp_llvm_sampler_lod_bias;
   sampler->dynamic_state.base.border_color = lp_llvm_sampler_border_color;
   sampler->dynamic_state.base.max_aniso = lp_llvm_sampler_max_aniso;

#if LP_USE_TEXTURE_CACHE
   sampler->dynamic_state.base.cache_ptr = lp_llvm_texture_cache_ptr;
#endif

   sampler->dynamic_state.static_state = static_state;

   sampler->nr_samplers = nr_samplers;
   return &sampler->base;
}


static void
lp_llvm_image_soa_destroy(struct lp_build_image_soa *image)
{
   FREE(image);
}


static void
lp_llvm_image_soa_emit_op(const struct lp_build_image_soa *base,
                             struct gallivm_state *gallivm,
                             const struct lp_img_params *params)
{
   struct lp_llvm_image_soa *image = (struct lp_llvm_image_soa *)base;
   const unsigned image_index = params->image_index;
   assert(image_index < PIPE_MAX_SHADER_IMAGES);

   if (params->image_index_offset) {
      struct lp_build_img_op_array_switch switch_info;
      memset(&switch_info, 0, sizeof(switch_info));
      LLVMValueRef unit = LLVMBuildAdd(gallivm->builder,
                                       params->image_index_offset,
                                       lp_build_const_int32(gallivm,
                                                            image_index), "");

      lp_build_image_op_switch_soa(&switch_info, gallivm, params,
                                   unit, 0, image->nr_images);

      for (unsigned i = 0; i < image->nr_images; i++) {
         lp_build_image_op_array_case(&switch_info, i,
                                      &image->dynamic_state.static_state[i].image_state,
                                      &image->dynamic_state.base);
      }
      lp_build_image_op_array_fini_soa(&switch_info);
   } else {
      lp_build_img_op_soa(&image->dynamic_state.static_state[image_index].image_state,
                          &image->dynamic_state.base,
                          gallivm, params, params->outdata);
   }
}


/**
 * Fetch the texture size.
 */
static void
lp_llvm_image_soa_emit_size_query(const struct lp_build_image_soa *base,
                                  struct gallivm_state *gallivm,
                                  const struct lp_sampler_size_query_params *params)
{
   struct lp_llvm_image_soa *image = (struct lp_llvm_image_soa *)base;

   assert(params->texture_unit < PIPE_MAX_SHADER_IMAGES);

   lp_build_size_query_soa(gallivm,
                           &image->dynamic_state.static_state[params->texture_unit].image_state,
                           &image->dynamic_state.base,
                           params);
}


struct lp_build_image_soa *
lp_llvm_image_soa_create(const struct lp_image_static_state *static_state,
                         unsigned nr_images)
{
   struct lp_llvm_image_soa *image = CALLOC_STRUCT(lp_llvm_image_soa);
   if (!image)
      return NULL;

   image->base.destroy = lp_llvm_image_soa_destroy;
   image->base.emit_op = lp_llvm_image_soa_emit_op;
   image->base.emit_size_query = lp_llvm_image_soa_emit_size_query;

   image->dynamic_state.base.width = lp_llvm_image_width;
   image->dynamic_state.base.height = lp_llvm_image_height;

   image->dynamic_state.base.depth = lp_llvm_image_depth;
   image->dynamic_state.base.base_ptr = lp_llvm_image_base_ptr;
   image->dynamic_state.base.row_stride = lp_llvm_image_row_stride;
   image->dynamic_state.base.img_stride = lp_llvm_image_img_stride;
   image->dynamic_state.base.num_samples = lp_llvm_image_num_samples;
   image->dynamic_state.base.sample_stride = lp_llvm_image_sample_stride;

   image->dynamic_state.static_state = static_state;

   image->nr_images = nr_images;
   return &image->base;
}