/************************************************************************** * * 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. * **************************************************************************/ /** * @file * Texture sampling -- common code. * * @author Jose Fonseca */ #include "pipe/p_defines.h" #include "pipe/p_state.h" #include "util/u_format.h" #include "util/u_math.h" #include "lp_bld_arit.h" #include "lp_bld_const.h" #include "lp_bld_debug.h" #include "lp_bld_printf.h" #include "lp_bld_flow.h" #include "lp_bld_sample.h" #include "lp_bld_swizzle.h" #include "lp_bld_type.h" /* * Bri-linear factor. Should be greater than one. */ #define BRILINEAR_FACTOR 2 /** * Does the given texture wrap mode allow sampling the texture border color? * XXX maybe move this into gallium util code. */ boolean lp_sampler_wrap_mode_uses_border_color(unsigned mode, unsigned min_img_filter, unsigned mag_img_filter) { switch (mode) { case PIPE_TEX_WRAP_REPEAT: case PIPE_TEX_WRAP_CLAMP_TO_EDGE: case PIPE_TEX_WRAP_MIRROR_REPEAT: case PIPE_TEX_WRAP_MIRROR_CLAMP_TO_EDGE: return FALSE; case PIPE_TEX_WRAP_CLAMP: case PIPE_TEX_WRAP_MIRROR_CLAMP: if (min_img_filter == PIPE_TEX_FILTER_NEAREST && mag_img_filter == PIPE_TEX_FILTER_NEAREST) { return FALSE; } else { return TRUE; } case PIPE_TEX_WRAP_CLAMP_TO_BORDER: case PIPE_TEX_WRAP_MIRROR_CLAMP_TO_BORDER: return TRUE; default: assert(0 && "unexpected wrap mode"); return FALSE; } } /** * Initialize lp_sampler_static_state object with the gallium sampler * and texture state. * The former is considered to be static and the later dynamic. */ void lp_sampler_static_state(struct lp_sampler_static_state *state, const struct pipe_sampler_view *view, const struct pipe_sampler_state *sampler) { const struct pipe_resource *texture = view->texture; memset(state, 0, sizeof *state); if(!texture) return; if(!sampler) return; /* * We don't copy sampler state over unless it is actually enabled, to avoid * spurious recompiles, as the sampler static state is part of the shader * key. * * Ideally the state tracker or cso_cache module would make all state * canonical, but until that happens it's better to be safe than sorry here. * * XXX: Actually there's much more than can be done here, especially * regarding 1D/2D/3D/CUBE textures, wrap modes, etc. */ state->format = view->format; state->swizzle_r = view->swizzle_r; state->swizzle_g = view->swizzle_g; state->swizzle_b = view->swizzle_b; state->swizzle_a = view->swizzle_a; state->target = texture->target; state->pot_width = util_is_power_of_two(texture->width0); state->pot_height = util_is_power_of_two(texture->height0); state->pot_depth = util_is_power_of_two(texture->depth0); state->wrap_s = sampler->wrap_s; state->wrap_t = sampler->wrap_t; state->wrap_r = sampler->wrap_r; state->min_img_filter = sampler->min_img_filter; state->mag_img_filter = sampler->mag_img_filter; if (view->u.tex.last_level && sampler->max_lod > 0.0f) { state->min_mip_filter = sampler->min_mip_filter; } else { state->min_mip_filter = PIPE_TEX_MIPFILTER_NONE; } if (state->min_mip_filter != PIPE_TEX_MIPFILTER_NONE) { if (sampler->lod_bias != 0.0f) { state->lod_bias_non_zero = 1; } /* If min_lod == max_lod we can greatly simplify mipmap selection. * This is a case that occurs during automatic mipmap generation. */ if (sampler->min_lod == sampler->max_lod) { state->min_max_lod_equal = 1; } else { if (sampler->min_lod > 0.0f) { state->apply_min_lod = 1; } if (sampler->max_lod < (float)view->u.tex.last_level) { state->apply_max_lod = 1; } } } state->compare_mode = sampler->compare_mode; if (sampler->compare_mode != PIPE_TEX_COMPARE_NONE) { state->compare_func = sampler->compare_func; } state->normalized_coords = sampler->normalized_coords; /* * FIXME: Handle the remainder of pipe_sampler_view. */ } /** * Generate code to compute coordinate gradient (rho). * \param ddx partial derivatives of (s, t, r, q) with respect to X * \param ddy partial derivatives of (s, t, r, q) with respect to Y * * XXX: The resulting rho is scalar, so we ignore all but the first element of * derivatives that are passed by the shader. */ static LLVMValueRef lp_build_rho(struct lp_build_sample_context *bld, const LLVMValueRef ddx[4], const LLVMValueRef ddy[4]) { struct lp_build_context *float_size_bld = &bld->float_size_bld; struct lp_build_context *float_bld = &bld->float_bld; const unsigned dims = bld->dims; LLVMBuilderRef builder = bld->gallivm->builder; LLVMTypeRef i32t = LLVMInt32TypeInContext(bld->gallivm->context); LLVMValueRef index0 = LLVMConstInt(i32t, 0, 0); LLVMValueRef index1 = LLVMConstInt(i32t, 1, 0); LLVMValueRef index2 = LLVMConstInt(i32t, 2, 0); LLVMValueRef dsdx, dsdy, dtdx, dtdy, drdx, drdy; LLVMValueRef rho_x, rho_y; LLVMValueRef rho_vec; LLVMValueRef float_size; LLVMValueRef rho; dsdx = ddx[0]; dsdy = ddy[0]; if (dims <= 1) { rho_x = dsdx; rho_y = dsdy; } else { rho_x = float_size_bld->undef; rho_y = float_size_bld->undef; rho_x = LLVMBuildInsertElement(builder, rho_x, dsdx, index0, ""); rho_y = LLVMBuildInsertElement(builder, rho_y, dsdy, index0, ""); dtdx = ddx[1]; dtdy = ddy[1]; rho_x = LLVMBuildInsertElement(builder, rho_x, dtdx, index1, ""); rho_y = LLVMBuildInsertElement(builder, rho_y, dtdy, index1, ""); if (dims >= 3) { drdx = ddx[2]; drdy = ddy[2]; rho_x = LLVMBuildInsertElement(builder, rho_x, drdx, index2, ""); rho_y = LLVMBuildInsertElement(builder, rho_y, drdy, index2, ""); } } rho_x = lp_build_abs(float_size_bld, rho_x); rho_y = lp_build_abs(float_size_bld, rho_y); rho_vec = lp_build_max(float_size_bld, rho_x, rho_y); float_size = lp_build_int_to_float(float_size_bld, bld->int_size); rho_vec = lp_build_mul(float_size_bld, rho_vec, float_size); if (dims <= 1) { rho = rho_vec; } else { if (dims >= 2) { LLVMValueRef rho_s, rho_t, rho_r; rho_s = LLVMBuildExtractElement(builder, rho_vec, index0, ""); rho_t = LLVMBuildExtractElement(builder, rho_vec, index1, ""); rho = lp_build_max(float_bld, rho_s, rho_t); if (dims >= 3) { rho_r = LLVMBuildExtractElement(builder, rho_vec, index0, ""); rho = lp_build_max(float_bld, rho, rho_r); } } } return rho; } /* * Bri-linear lod computation * * Use a piece-wise linear approximation of log2 such that: * - round to nearest, for values in the neighborhood of -1, 0, 1, 2, etc. * - linear approximation for values in the neighborhood of 0.5, 1.5., etc, * with the steepness specified in 'factor' * - exact result for 0.5, 1.5, etc. * * * 1.0 - /----* * / * / * / * 0.5 - * * / * / * / * 0.0 - *----/ * * | | * 2^0 2^1 * * This is a technique also commonly used in hardware: * - http://ixbtlabs.com/articles2/gffx/nv40-rx800-3.html * * TODO: For correctness, this should only be applied when texture is known to * have regular mipmaps, i.e., mipmaps derived from the base level. * * TODO: This could be done in fixed point, where applicable. */ static void lp_build_brilinear_lod(struct lp_build_context *bld, LLVMValueRef lod, double factor, LLVMValueRef *out_lod_ipart, LLVMValueRef *out_lod_fpart) { LLVMValueRef lod_fpart; double pre_offset = (factor - 0.5)/factor - 0.5; double post_offset = 1 - factor; if (0) { lp_build_printf(bld->gallivm, "lod = %f\n", lod); } lod = lp_build_add(bld, lod, lp_build_const_vec(bld->gallivm, bld->type, pre_offset)); lp_build_ifloor_fract(bld, lod, out_lod_ipart, &lod_fpart); lod_fpart = lp_build_mul(bld, lod_fpart, lp_build_const_vec(bld->gallivm, bld->type, factor)); lod_fpart = lp_build_add(bld, lod_fpart, lp_build_const_vec(bld->gallivm, bld->type, post_offset)); /* * It's not necessary to clamp lod_fpart since: * - the above expression will never produce numbers greater than one. * - the mip filtering branch is only taken if lod_fpart is positive */ *out_lod_fpart = lod_fpart; if (0) { lp_build_printf(bld->gallivm, "lod_ipart = %i\n", *out_lod_ipart); lp_build_printf(bld->gallivm, "lod_fpart = %f\n\n", *out_lod_fpart); } } /* * Combined log2 and brilinear lod computation. * * It's in all identical to calling lp_build_fast_log2() and * lp_build_brilinear_lod() above, but by combining we can compute the interger * and fractional part independently. */ static void lp_build_brilinear_rho(struct lp_build_context *bld, LLVMValueRef rho, double factor, LLVMValueRef *out_lod_ipart, LLVMValueRef *out_lod_fpart) { LLVMValueRef lod_ipart; LLVMValueRef lod_fpart; const double pre_factor = (2*factor - 0.5)/(M_SQRT2*factor); const double post_offset = 1 - 2*factor; assert(bld->type.floating); assert(lp_check_value(bld->type, rho)); /* * The pre factor will make the intersections with the exact powers of two * happen precisely where we want then to be, which means that the integer * part will not need any post adjustments. */ rho = lp_build_mul(bld, rho, lp_build_const_vec(bld->gallivm, bld->type, pre_factor)); /* ipart = ifloor(log2(rho)) */ lod_ipart = lp_build_extract_exponent(bld, rho, 0); /* fpart = rho / 2**ipart */ lod_fpart = lp_build_extract_mantissa(bld, rho); lod_fpart = lp_build_mul(bld, lod_fpart, lp_build_const_vec(bld->gallivm, bld->type, factor)); lod_fpart = lp_build_add(bld, lod_fpart, lp_build_const_vec(bld->gallivm, bld->type, post_offset)); /* * Like lp_build_brilinear_lod, it's not necessary to clamp lod_fpart since: * - the above expression will never produce numbers greater than one. * - the mip filtering branch is only taken if lod_fpart is positive */ *out_lod_ipart = lod_ipart; *out_lod_fpart = lod_fpart; } /** * Generate code to compute texture level of detail (lambda). * \param ddx partial derivatives of (s, t, r, q) with respect to X * \param ddy partial derivatives of (s, t, r, q) with respect to Y * \param lod_bias optional float vector with the shader lod bias * \param explicit_lod optional float vector with the explicit lod * \param width scalar int texture width * \param height scalar int texture height * \param depth scalar int texture depth * * XXX: The resulting lod is scalar, so ignore all but the first element of * derivatives, lod_bias, etc that are passed by the shader. */ void lp_build_lod_selector(struct lp_build_sample_context *bld, unsigned unit, const LLVMValueRef ddx[4], const LLVMValueRef ddy[4], LLVMValueRef lod_bias, /* optional */ LLVMValueRef explicit_lod, /* optional */ unsigned mip_filter, LLVMValueRef *out_lod_ipart, LLVMValueRef *out_lod_fpart) { LLVMBuilderRef builder = bld->gallivm->builder; struct lp_build_context *float_bld = &bld->float_bld; LLVMValueRef lod; *out_lod_ipart = bld->int_bld.zero; *out_lod_fpart = bld->float_bld.zero; if (bld->static_state->min_max_lod_equal) { /* User is forcing sampling from a particular mipmap level. * This is hit during mipmap generation. */ LLVMValueRef min_lod = bld->dynamic_state->min_lod(bld->dynamic_state, bld->gallivm, unit); lod = min_lod; } else { LLVMValueRef sampler_lod_bias = bld->dynamic_state->lod_bias(bld->dynamic_state, bld->gallivm, unit); LLVMValueRef index0 = lp_build_const_int32(bld->gallivm, 0); if (explicit_lod) { lod = LLVMBuildExtractElement(builder, explicit_lod, index0, ""); } else { LLVMValueRef rho; rho = lp_build_rho(bld, ddx, ddy); /* * Compute lod = log2(rho) */ if (!lod_bias && !bld->static_state->lod_bias_non_zero && !bld->static_state->apply_max_lod && !bld->static_state->apply_min_lod) { /* * Special case when there are no post-log2 adjustments, which * saves instructions but keeping the integer and fractional lod * computations separate from the start. */ if (mip_filter == PIPE_TEX_MIPFILTER_NONE || mip_filter == PIPE_TEX_MIPFILTER_NEAREST) { *out_lod_ipart = lp_build_ilog2(float_bld, rho); *out_lod_fpart = bld->float_bld.zero; return; } if (mip_filter == PIPE_TEX_MIPFILTER_LINEAR && !(gallivm_debug & GALLIVM_DEBUG_NO_BRILINEAR)) { lp_build_brilinear_rho(float_bld, rho, BRILINEAR_FACTOR, out_lod_ipart, out_lod_fpart); return; } } if (0) { lod = lp_build_log2(float_bld, rho); } else { lod = lp_build_fast_log2(float_bld, rho); } /* add shader lod bias */ if (lod_bias) { lod_bias = LLVMBuildExtractElement(builder, lod_bias, index0, ""); lod = LLVMBuildFAdd(builder, lod, lod_bias, "shader_lod_bias"); } } /* add sampler lod bias */ if (bld->static_state->lod_bias_non_zero) lod = LLVMBuildFAdd(builder, lod, sampler_lod_bias, "sampler_lod_bias"); /* clamp lod */ if (bld->static_state->apply_max_lod) { LLVMValueRef max_lod = bld->dynamic_state->max_lod(bld->dynamic_state, bld->gallivm, unit); lod = lp_build_min(float_bld, lod, max_lod); } if (bld->static_state->apply_min_lod) { LLVMValueRef min_lod = bld->dynamic_state->min_lod(bld->dynamic_state, bld->gallivm, unit); lod = lp_build_max(float_bld, lod, min_lod); } } if (mip_filter == PIPE_TEX_MIPFILTER_LINEAR) { if (!(gallivm_debug & GALLIVM_DEBUG_NO_BRILINEAR)) { lp_build_brilinear_lod(float_bld, lod, BRILINEAR_FACTOR, out_lod_ipart, out_lod_fpart); } else { lp_build_ifloor_fract(float_bld, lod, out_lod_ipart, out_lod_fpart); } lp_build_name(*out_lod_fpart, "lod_fpart"); } else { *out_lod_ipart = lp_build_iround(float_bld, lod); } lp_build_name(*out_lod_ipart, "lod_ipart"); return; } /** * For PIPE_TEX_MIPFILTER_NEAREST, convert float LOD to integer * mipmap level index. * Note: this is all scalar code. * \param lod scalar float texture level of detail * \param level_out returns integer */ void lp_build_nearest_mip_level(struct lp_build_sample_context *bld, unsigned unit, LLVMValueRef lod_ipart, LLVMValueRef *level_out) { struct lp_build_context *int_bld = &bld->int_bld; LLVMValueRef last_level, level; LLVMValueRef zero = lp_build_const_int32(bld->gallivm, 0); last_level = bld->dynamic_state->last_level(bld->dynamic_state, bld->gallivm, unit); /* convert float lod to integer */ level = lod_ipart; /* clamp level to legal range of levels */ *level_out = lp_build_clamp(int_bld, level, zero, last_level); } /** * For PIPE_TEX_MIPFILTER_LINEAR, convert float LOD to integer to * two (adjacent) mipmap level indexes. Later, we'll sample from those * two mipmap levels and interpolate between them. */ void lp_build_linear_mip_levels(struct lp_build_sample_context *bld, unsigned unit, LLVMValueRef lod_ipart, LLVMValueRef *lod_fpart_inout, LLVMValueRef *level0_out, LLVMValueRef *level1_out) { LLVMBuilderRef builder = bld->gallivm->builder; struct lp_build_context *int_bld = &bld->int_bld; struct lp_build_context *float_bld = &bld->float_bld; LLVMValueRef last_level; LLVMValueRef clamp_min; LLVMValueRef clamp_max; *level0_out = lod_ipart; *level1_out = lp_build_add(int_bld, lod_ipart, int_bld->one); last_level = bld->dynamic_state->last_level(bld->dynamic_state, bld->gallivm, unit); /* * Clamp both lod_ipart and lod_ipart + 1 to [0, last_level], with the * minimum number of comparisons, and zeroing lod_fpart in the extreme * ends in the process. */ /* lod_ipart < 0 */ clamp_min = LLVMBuildICmp(builder, LLVMIntSLT, lod_ipart, int_bld->zero, "clamp_lod_to_zero"); *level0_out = LLVMBuildSelect(builder, clamp_min, int_bld->zero, *level0_out, ""); *level1_out = LLVMBuildSelect(builder, clamp_min, int_bld->zero, *level1_out, ""); *lod_fpart_inout = LLVMBuildSelect(builder, clamp_min, float_bld->zero, *lod_fpart_inout, ""); /* lod_ipart >= last_level */ clamp_max = LLVMBuildICmp(builder, LLVMIntSGE, lod_ipart, last_level, "clamp_lod_to_last"); *level0_out = LLVMBuildSelect(builder, clamp_max, last_level, *level0_out, ""); *level1_out = LLVMBuildSelect(builder, clamp_max, last_level, *level1_out, ""); *lod_fpart_inout = LLVMBuildSelect(builder, clamp_max, float_bld->zero, *lod_fpart_inout, ""); lp_build_name(*level0_out, "sampler%u_miplevel0", unit); lp_build_name(*level1_out, "sampler%u_miplevel1", unit); lp_build_name(*lod_fpart_inout, "sampler%u_mipweight", unit); } /** * Return pointer to a single mipmap level. * \param data_array array of pointers to mipmap levels * \param level integer mipmap level */ LLVMValueRef lp_build_get_mipmap_level(struct lp_build_sample_context *bld, LLVMValueRef level) { LLVMBuilderRef builder = bld->gallivm->builder; LLVMValueRef indexes[2], data_ptr; indexes[0] = lp_build_const_int32(bld->gallivm, 0); indexes[1] = level; data_ptr = LLVMBuildGEP(builder, bld->data_array, indexes, 2, ""); data_ptr = LLVMBuildLoad(builder, data_ptr, ""); return data_ptr; } LLVMValueRef lp_build_get_const_mipmap_level(struct lp_build_sample_context *bld, int level) { LLVMValueRef lvl = lp_build_const_int32(bld->gallivm, level); return lp_build_get_mipmap_level(bld, lvl); } /** * Codegen equivalent for u_minify(). * Return max(1, base_size >> level); */ static LLVMValueRef lp_build_minify(struct lp_build_context *bld, LLVMValueRef base_size, LLVMValueRef level) { LLVMBuilderRef builder = bld->gallivm->builder; assert(lp_check_value(bld->type, base_size)); assert(lp_check_value(bld->type, level)); if (level == bld->zero) { /* if we're using mipmap level zero, no minification is needed */ return base_size; } else { LLVMValueRef size = LLVMBuildLShr(builder, base_size, level, "minify"); assert(bld->type.sign); size = lp_build_max(bld, size, bld->one); return size; } } /** * Dereference stride_array[mipmap_level] array to get a stride. * Return stride as a vector. */ static LLVMValueRef lp_build_get_level_stride_vec(struct lp_build_sample_context *bld, LLVMValueRef stride_array, LLVMValueRef level) { LLVMBuilderRef builder = bld->gallivm->builder; LLVMValueRef indexes[2], stride; indexes[0] = lp_build_const_int32(bld->gallivm, 0); indexes[1] = level; stride = LLVMBuildGEP(builder, stride_array, indexes, 2, ""); stride = LLVMBuildLoad(builder, stride, ""); stride = lp_build_broadcast_scalar(&bld->int_coord_bld, stride); return stride; } /** * When sampling a mipmap, we need to compute the width, height, depth * of the source levels from the level indexes. This helper function * does that. */ void lp_build_mipmap_level_sizes(struct lp_build_sample_context *bld, LLVMValueRef ilevel, LLVMValueRef *out_size, LLVMValueRef *row_stride_vec, LLVMValueRef *img_stride_vec) { const unsigned dims = bld->dims; LLVMValueRef ilevel_vec; ilevel_vec = lp_build_broadcast_scalar(&bld->int_size_bld, ilevel); /* * Compute width, height, depth at mipmap level 'ilevel' */ *out_size = lp_build_minify(&bld->int_size_bld, bld->int_size, ilevel_vec); if (dims >= 2) { *row_stride_vec = lp_build_get_level_stride_vec(bld, bld->row_stride_array, ilevel); if (dims == 3 || bld->static_state->target == PIPE_TEXTURE_CUBE) { *img_stride_vec = lp_build_get_level_stride_vec(bld, bld->img_stride_array, ilevel); } } } /** * Extract and broadcast texture size. * * @param size_type type of the texture size vector (either * bld->int_size_type or bld->float_size_type) * @param coord_type type of the texture size vector (either * bld->int_coord_type or bld->coord_type) * @param int_size vector with the integer texture size (width, height, * depth) */ void lp_build_extract_image_sizes(struct lp_build_sample_context *bld, struct lp_type size_type, struct lp_type coord_type, LLVMValueRef size, LLVMValueRef *out_width, LLVMValueRef *out_height, LLVMValueRef *out_depth) { const unsigned dims = bld->dims; LLVMTypeRef i32t = LLVMInt32TypeInContext(bld->gallivm->context); *out_width = lp_build_extract_broadcast(bld->gallivm, size_type, coord_type, size, LLVMConstInt(i32t, 0, 0)); if (dims >= 2) { *out_height = lp_build_extract_broadcast(bld->gallivm, size_type, coord_type, size, LLVMConstInt(i32t, 1, 0)); if (dims == 3) { *out_depth = lp_build_extract_broadcast(bld->gallivm, size_type, coord_type, size, LLVMConstInt(i32t, 2, 0)); } } } /** * Unnormalize coords. * * @param int_size vector with the integer texture size (width, height, depth) */ void lp_build_unnormalized_coords(struct lp_build_sample_context *bld, LLVMValueRef flt_size, LLVMValueRef *s, LLVMValueRef *t, LLVMValueRef *r) { const unsigned dims = bld->dims; LLVMValueRef width; LLVMValueRef height; LLVMValueRef depth; lp_build_extract_image_sizes(bld, bld->float_size_type, bld->coord_type, flt_size, &width, &height, &depth); /* s = s * width, t = t * height */ *s = lp_build_mul(&bld->coord_bld, *s, width); if (dims >= 2) { *t = lp_build_mul(&bld->coord_bld, *t, height); if (dims >= 3) { *r = lp_build_mul(&bld->coord_bld, *r, depth); } } } /** Helper used by lp_build_cube_lookup() */ static LLVMValueRef lp_build_cube_ima(struct lp_build_context *coord_bld, LLVMValueRef coord) { /* ima = -0.5 / abs(coord); */ LLVMValueRef negHalf = lp_build_const_vec(coord_bld->gallivm, coord_bld->type, -0.5); LLVMValueRef absCoord = lp_build_abs(coord_bld, coord); LLVMValueRef ima = lp_build_div(coord_bld, negHalf, absCoord); return ima; } /** * Helper used by lp_build_cube_lookup() * \param sign scalar +1 or -1 * \param coord float vector * \param ima float vector */ static LLVMValueRef lp_build_cube_coord(struct lp_build_context *coord_bld, LLVMValueRef sign, int negate_coord, LLVMValueRef coord, LLVMValueRef ima) { /* return negate(coord) * ima * sign + 0.5; */ LLVMValueRef half = lp_build_const_vec(coord_bld->gallivm, coord_bld->type, 0.5); LLVMValueRef res; assert(negate_coord == +1 || negate_coord == -1); if (negate_coord == -1) { coord = lp_build_negate(coord_bld, coord); } res = lp_build_mul(coord_bld, coord, ima); if (sign) { sign = lp_build_broadcast_scalar(coord_bld, sign); res = lp_build_mul(coord_bld, res, sign); } res = lp_build_add(coord_bld, res, half); return res; } /** Helper used by lp_build_cube_lookup() * Return (major_coord >= 0) ? pos_face : neg_face; */ static LLVMValueRef lp_build_cube_face(struct lp_build_sample_context *bld, LLVMValueRef major_coord, unsigned pos_face, unsigned neg_face) { struct gallivm_state *gallivm = bld->gallivm; LLVMBuilderRef builder = gallivm->builder; LLVMValueRef cmp = LLVMBuildFCmp(builder, LLVMRealUGE, major_coord, bld->float_bld.zero, ""); LLVMValueRef pos = lp_build_const_int32(gallivm, pos_face); LLVMValueRef neg = lp_build_const_int32(gallivm, neg_face); LLVMValueRef res = LLVMBuildSelect(builder, cmp, pos, neg, ""); return res; } /** * Generate code to do cube face selection and compute per-face texcoords. */ void lp_build_cube_lookup(struct lp_build_sample_context *bld, LLVMValueRef s, LLVMValueRef t, LLVMValueRef r, LLVMValueRef *face, LLVMValueRef *face_s, LLVMValueRef *face_t) { struct lp_build_context *float_bld = &bld->float_bld; struct lp_build_context *coord_bld = &bld->coord_bld; LLVMBuilderRef builder = bld->gallivm->builder; LLVMValueRef rx, ry, rz; LLVMValueRef arx, ary, arz; LLVMValueRef c25 = lp_build_const_float(bld->gallivm, 0.25); LLVMValueRef arx_ge_ary, arx_ge_arz; LLVMValueRef ary_ge_arx, ary_ge_arz; LLVMValueRef arx_ge_ary_arz, ary_ge_arx_arz; LLVMValueRef rx_pos, ry_pos, rz_pos; assert(bld->coord_bld.type.length == 4); /* * Use the average of the four pixel's texcoords to choose the face. */ rx = lp_build_mul(float_bld, c25, lp_build_sum_vector(&bld->coord_bld, s)); ry = lp_build_mul(float_bld, c25, lp_build_sum_vector(&bld->coord_bld, t)); rz = lp_build_mul(float_bld, c25, lp_build_sum_vector(&bld->coord_bld, r)); arx = lp_build_abs(float_bld, rx); ary = lp_build_abs(float_bld, ry); arz = lp_build_abs(float_bld, rz); /* * Compare sign/magnitude of rx,ry,rz to determine face */ arx_ge_ary = LLVMBuildFCmp(builder, LLVMRealUGE, arx, ary, ""); arx_ge_arz = LLVMBuildFCmp(builder, LLVMRealUGE, arx, arz, ""); ary_ge_arx = LLVMBuildFCmp(builder, LLVMRealUGE, ary, arx, ""); ary_ge_arz = LLVMBuildFCmp(builder, LLVMRealUGE, ary, arz, ""); arx_ge_ary_arz = LLVMBuildAnd(builder, arx_ge_ary, arx_ge_arz, ""); ary_ge_arx_arz = LLVMBuildAnd(builder, ary_ge_arx, ary_ge_arz, ""); rx_pos = LLVMBuildFCmp(builder, LLVMRealUGE, rx, float_bld->zero, ""); ry_pos = LLVMBuildFCmp(builder, LLVMRealUGE, ry, float_bld->zero, ""); rz_pos = LLVMBuildFCmp(builder, LLVMRealUGE, rz, float_bld->zero, ""); { struct lp_build_if_state if_ctx; LLVMValueRef face_s_var; LLVMValueRef face_t_var; LLVMValueRef face_var; face_s_var = lp_build_alloca(bld->gallivm, bld->coord_bld.vec_type, "face_s_var"); face_t_var = lp_build_alloca(bld->gallivm, bld->coord_bld.vec_type, "face_t_var"); face_var = lp_build_alloca(bld->gallivm, bld->int_bld.vec_type, "face_var"); lp_build_if(&if_ctx, bld->gallivm, arx_ge_ary_arz); { /* +/- X face */ LLVMValueRef sign = lp_build_sgn(float_bld, rx); LLVMValueRef ima = lp_build_cube_ima(coord_bld, s); *face_s = lp_build_cube_coord(coord_bld, sign, +1, r, ima); *face_t = lp_build_cube_coord(coord_bld, NULL, +1, t, ima); *face = lp_build_cube_face(bld, rx, PIPE_TEX_FACE_POS_X, PIPE_TEX_FACE_NEG_X); LLVMBuildStore(builder, *face_s, face_s_var); LLVMBuildStore(builder, *face_t, face_t_var); LLVMBuildStore(builder, *face, face_var); } lp_build_else(&if_ctx); { struct lp_build_if_state if_ctx2; ary_ge_arx_arz = LLVMBuildAnd(builder, ary_ge_arx, ary_ge_arz, ""); lp_build_if(&if_ctx2, bld->gallivm, ary_ge_arx_arz); { /* +/- Y face */ LLVMValueRef sign = lp_build_sgn(float_bld, ry); LLVMValueRef ima = lp_build_cube_ima(coord_bld, t); *face_s = lp_build_cube_coord(coord_bld, NULL, -1, s, ima); *face_t = lp_build_cube_coord(coord_bld, sign, -1, r, ima); *face = lp_build_cube_face(bld, ry, PIPE_TEX_FACE_POS_Y, PIPE_TEX_FACE_NEG_Y); LLVMBuildStore(builder, *face_s, face_s_var); LLVMBuildStore(builder, *face_t, face_t_var); LLVMBuildStore(builder, *face, face_var); } lp_build_else(&if_ctx2); { /* +/- Z face */ LLVMValueRef sign = lp_build_sgn(float_bld, rz); LLVMValueRef ima = lp_build_cube_ima(coord_bld, r); *face_s = lp_build_cube_coord(coord_bld, sign, -1, s, ima); *face_t = lp_build_cube_coord(coord_bld, NULL, +1, t, ima); *face = lp_build_cube_face(bld, rz, PIPE_TEX_FACE_POS_Z, PIPE_TEX_FACE_NEG_Z); LLVMBuildStore(builder, *face_s, face_s_var); LLVMBuildStore(builder, *face_t, face_t_var); LLVMBuildStore(builder, *face, face_var); } lp_build_endif(&if_ctx2); } lp_build_endif(&if_ctx); *face_s = LLVMBuildLoad(builder, face_s_var, "face_s"); *face_t = LLVMBuildLoad(builder, face_t_var, "face_t"); *face = LLVMBuildLoad(builder, face_var, "face"); } } /** * Compute the partial offset of a pixel block along an arbitrary axis. * * @param coord coordinate in pixels * @param stride number of bytes between rows of successive pixel blocks * @param block_length number of pixels in a pixels block along the coordinate * axis * @param out_offset resulting relative offset of the pixel block in bytes * @param out_subcoord resulting sub-block pixel coordinate */ void lp_build_sample_partial_offset(struct lp_build_context *bld, unsigned block_length, LLVMValueRef coord, LLVMValueRef stride, LLVMValueRef *out_offset, LLVMValueRef *out_subcoord) { LLVMBuilderRef builder = bld->gallivm->builder; LLVMValueRef offset; LLVMValueRef subcoord; if (block_length == 1) { subcoord = bld->zero; } else { /* * Pixel blocks have power of two dimensions. LLVM should convert the * rem/div to bit arithmetic. * TODO: Verify this. * It does indeed BUT it does transform it to scalar (and back) when doing so * (using roughly extract, shift/and, mov, unpack) (llvm 2.7). * The generated code looks seriously unfunny and is quite expensive. */ #if 0 LLVMValueRef block_width = lp_build_const_int_vec(bld->type, block_length); subcoord = LLVMBuildURem(builder, coord, block_width, ""); coord = LLVMBuildUDiv(builder, coord, block_width, ""); #else unsigned logbase2 = util_unsigned_logbase2(block_length); LLVMValueRef block_shift = lp_build_const_int_vec(bld->gallivm, bld->type, logbase2); LLVMValueRef block_mask = lp_build_const_int_vec(bld->gallivm, bld->type, block_length - 1); subcoord = LLVMBuildAnd(builder, coord, block_mask, ""); coord = LLVMBuildLShr(builder, coord, block_shift, ""); #endif } offset = lp_build_mul(bld, coord, stride); assert(out_offset); assert(out_subcoord); *out_offset = offset; *out_subcoord = subcoord; } /** * Compute the offset of a pixel block. * * x, y, z, y_stride, z_stride are vectors, and they refer to pixels. * * Returns the relative offset and i,j sub-block coordinates */ void lp_build_sample_offset(struct lp_build_context *bld, const struct util_format_description *format_desc, LLVMValueRef x, LLVMValueRef y, LLVMValueRef z, LLVMValueRef y_stride, LLVMValueRef z_stride, LLVMValueRef *out_offset, LLVMValueRef *out_i, LLVMValueRef *out_j) { LLVMValueRef x_stride; LLVMValueRef offset; x_stride = lp_build_const_vec(bld->gallivm, bld->type, format_desc->block.bits/8); lp_build_sample_partial_offset(bld, format_desc->block.width, x, x_stride, &offset, out_i); if (y && y_stride) { LLVMValueRef y_offset; lp_build_sample_partial_offset(bld, format_desc->block.height, y, y_stride, &y_offset, out_j); offset = lp_build_add(bld, offset, y_offset); } else { *out_j = bld->zero; } if (z && z_stride) { LLVMValueRef z_offset; LLVMValueRef k; lp_build_sample_partial_offset(bld, 1, /* pixel blocks are always 2D */ z, z_stride, &z_offset, &k); offset = lp_build_add(bld, offset, z_offset); } *out_offset = offset; }