lp_bld_blend_soa.c revision f795735f4251d5f7842ee9e09994641c5c46d25d
1/************************************************************************** 2 * 3 * Copyright 2009 VMware, Inc. 4 * All Rights Reserved. 5 * 6 * Permission is hereby granted, free of charge, to any person obtaining a 7 * copy of this software and associated documentation files (the 8 * "Software"), to deal in the Software without restriction, including 9 * without limitation the rights to use, copy, modify, merge, publish, 10 * distribute, sub license, and/or sell copies of the Software, and to 11 * permit persons to whom the Software is furnished to do so, subject to 12 * the following conditions: 13 * 14 * The above copyright notice and this permission notice (including the 15 * next paragraph) shall be included in all copies or substantial portions 16 * of the Software. 17 * 18 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS 19 * OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF 20 * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NON-INFRINGEMENT. 21 * IN NO EVENT SHALL VMWARE AND/OR ITS SUPPLIERS BE LIABLE FOR 22 * ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT, 23 * TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE 24 * SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE. 25 * 26 **************************************************************************/ 27 28 29/** 30 * @file 31 * Blend LLVM IR generation -- SoA layout. 32 * 33 * Blending in SoA is much faster than AoS, especially when separate rgb/alpha 34 * factors/functions are used, since no channel masking/shuffling is necessary 35 * and we can achieve the full throughput of the SIMD operations. Furthermore 36 * the fragment shader output is also in SoA, so it fits nicely with the rest 37 * of the fragment pipeline. 38 * 39 * The drawback is that to be displayed the color buffer needs to be in AoS 40 * layout, so we need to tile/untile the color buffer before/after rendering. 41 * A color buffer like 42 * 43 * R11 G11 B11 A11 R12 G12 B12 A12 R13 G13 B13 A13 R14 G14 B14 A14 ... 44 * R21 G21 B21 A21 R22 G22 B22 A22 R23 G23 B23 A23 R24 G24 B24 A24 ... 45 * 46 * R31 G31 B31 A31 R32 G32 B32 A32 R33 G33 B33 A33 R34 G34 B34 A34 ... 47 * R41 G41 B41 A41 R42 G42 B42 A42 R43 G43 B43 A43 R44 G44 B44 A44 ... 48 * 49 * ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 50 * 51 * will actually be stored in memory as 52 * 53 * R11 R12 R21 R22 R13 R14 R23 R24 ... G11 G12 G21 G22 G13 G14 G23 G24 ... B11 B12 B21 B22 B13 B14 B23 B24 ... A11 A12 A21 A22 A13 A14 A23 A24 ... 54 * R31 R32 R41 R42 R33 R34 R43 R44 ... G31 G32 G41 G42 G33 G34 G43 G44 ... B31 B32 B41 B42 B33 B34 B43 B44 ... A31 A32 A41 A42 A33 A34 A43 A44 ... 55 * ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... ... 56 * 57 * NOTE: Run lp_blend_test after any change to this file. 58 * 59 * You can also run lp_blend_test to obtain AoS vs SoA benchmarks. Invoking it 60 * as: 61 * 62 * lp_blend_test -o blend.tsv 63 * 64 * will generate a tab-seperated-file with the test results and performance 65 * measurements. 66 * 67 * @author Jose Fonseca <jfonseca@vmware.com> 68 */ 69 70 71#include "pipe/p_state.h" 72#include "util/u_debug.h" 73 74#include "gallivm/lp_bld_type.h" 75#include "gallivm/lp_bld_arit.h" 76#include "lp_bld_blend.h" 77 78 79/** 80 * We may use the same values several times, so we keep them here to avoid 81 * recomputing them. Also reusing the values allows us to do simplifications 82 * that LLVM optimization passes wouldn't normally be able to do. 83 */ 84struct lp_build_blend_soa_context 85{ 86 struct lp_build_context base; 87 88 LLVMValueRef src[4]; 89 LLVMValueRef dst[4]; 90 LLVMValueRef con[4]; 91 92 LLVMValueRef inv_src[4]; 93 LLVMValueRef inv_dst[4]; 94 LLVMValueRef inv_con[4]; 95 96 LLVMValueRef src_alpha_saturate; 97 98 /** 99 * We store all factors in a table in order to eliminate redundant 100 * multiplications later. 101 * Indexes are: factor[src,dst][color,term][r,g,b,a] 102 */ 103 LLVMValueRef factor[2][2][4]; 104 105 /** 106 * Table with all terms. 107 * Indexes are: term[src,dst][r,g,b,a] 108 */ 109 LLVMValueRef term[2][4]; 110}; 111 112 113/** 114 * Build a single SOA blend factor for a color channel. 115 * \param i the color channel in [0,3] 116 */ 117static LLVMValueRef 118lp_build_blend_soa_factor(struct lp_build_blend_soa_context *bld, 119 unsigned factor, unsigned i) 120{ 121 /* 122 * Compute src/first term RGB 123 */ 124 switch (factor) { 125 case PIPE_BLENDFACTOR_ONE: 126 return bld->base.one; 127 case PIPE_BLENDFACTOR_SRC_COLOR: 128 return bld->src[i]; 129 case PIPE_BLENDFACTOR_SRC_ALPHA: 130 return bld->src[3]; 131 case PIPE_BLENDFACTOR_DST_COLOR: 132 return bld->dst[i]; 133 case PIPE_BLENDFACTOR_DST_ALPHA: 134 return bld->dst[3]; 135 case PIPE_BLENDFACTOR_SRC_ALPHA_SATURATE: 136 if(i == 3) 137 return bld->base.one; 138 else { 139 if(!bld->inv_dst[3]) 140 bld->inv_dst[3] = lp_build_comp(&bld->base, bld->dst[3]); 141 if(!bld->src_alpha_saturate) 142 bld->src_alpha_saturate = lp_build_min(&bld->base, bld->src[3], bld->inv_dst[3]); 143 return bld->src_alpha_saturate; 144 } 145 case PIPE_BLENDFACTOR_CONST_COLOR: 146 return bld->con[i]; 147 case PIPE_BLENDFACTOR_CONST_ALPHA: 148 return bld->con[3]; 149 case PIPE_BLENDFACTOR_SRC1_COLOR: 150 /* TODO */ 151 assert(0); 152 return bld->base.zero; 153 case PIPE_BLENDFACTOR_SRC1_ALPHA: 154 /* TODO */ 155 assert(0); 156 return bld->base.zero; 157 case PIPE_BLENDFACTOR_ZERO: 158 return bld->base.zero; 159 case PIPE_BLENDFACTOR_INV_SRC_COLOR: 160 if(!bld->inv_src[i]) 161 bld->inv_src[i] = lp_build_comp(&bld->base, bld->src[i]); 162 return bld->inv_src[i]; 163 case PIPE_BLENDFACTOR_INV_SRC_ALPHA: 164 if(!bld->inv_src[3]) 165 bld->inv_src[3] = lp_build_comp(&bld->base, bld->src[3]); 166 return bld->inv_src[3]; 167 case PIPE_BLENDFACTOR_INV_DST_COLOR: 168 if(!bld->inv_dst[i]) 169 bld->inv_dst[i] = lp_build_comp(&bld->base, bld->dst[i]); 170 return bld->inv_dst[i]; 171 case PIPE_BLENDFACTOR_INV_DST_ALPHA: 172 if(!bld->inv_dst[3]) 173 bld->inv_dst[3] = lp_build_comp(&bld->base, bld->dst[3]); 174 return bld->inv_dst[3]; 175 case PIPE_BLENDFACTOR_INV_CONST_COLOR: 176 if(!bld->inv_con[i]) 177 bld->inv_con[i] = lp_build_comp(&bld->base, bld->con[i]); 178 return bld->inv_con[i]; 179 case PIPE_BLENDFACTOR_INV_CONST_ALPHA: 180 if(!bld->inv_con[3]) 181 bld->inv_con[3] = lp_build_comp(&bld->base, bld->con[3]); 182 return bld->inv_con[3]; 183 case PIPE_BLENDFACTOR_INV_SRC1_COLOR: 184 /* TODO */ 185 assert(0); 186 return bld->base.zero; 187 case PIPE_BLENDFACTOR_INV_SRC1_ALPHA: 188 /* TODO */ 189 assert(0); 190 return bld->base.zero; 191 default: 192 assert(0); 193 return bld->base.zero; 194 } 195} 196 197 198/** 199 * Generate blend code in SOA mode. 200 * \param rt render target index (to index the blend / colormask state) 201 * \param src src/fragment color 202 * \param dst dst/framebuffer color 203 * \param con constant blend color 204 * \param res the result/output 205 */ 206void 207lp_build_blend_soa(LLVMBuilderRef builder, 208 const struct pipe_blend_state *blend, 209 struct lp_type type, 210 unsigned rt, 211 LLVMValueRef src[4], 212 LLVMValueRef dst[4], 213 LLVMValueRef con[4], 214 LLVMValueRef res[4]) 215{ 216 struct lp_build_blend_soa_context bld; 217 unsigned i, j, k; 218 219 assert(rt < PIPE_MAX_COLOR_BUFS); 220 221 /* Setup build context */ 222 memset(&bld, 0, sizeof bld); 223 lp_build_context_init(&bld.base, builder, type); 224 for (i = 0; i < 4; ++i) { 225 bld.src[i] = src[i]; 226 bld.dst[i] = dst[i]; 227 bld.con[i] = con[i]; 228 } 229 230 for (i = 0; i < 4; ++i) { 231 /* only compute blending for the color channels enabled for writing */ 232 if (blend->rt[rt].colormask & (1 << i)) { 233 if (blend->logicop_enable) { 234 if(!type.floating) { 235 res[i] = lp_build_logicop(builder, blend->logicop_func, src[i], dst[i]); 236 } 237 else 238 res[i] = dst[i]; 239 } 240 else if (blend->rt[rt].blend_enable) { 241 unsigned src_factor = i < 3 ? blend->rt[rt].rgb_src_factor : blend->rt[rt].alpha_src_factor; 242 unsigned dst_factor = i < 3 ? blend->rt[rt].rgb_dst_factor : blend->rt[rt].alpha_dst_factor; 243 unsigned func = i < 3 ? blend->rt[rt].rgb_func : blend->rt[rt].alpha_func; 244 boolean func_commutative = lp_build_blend_func_commutative(func); 245 246 /* It makes no sense to blend unless values are normalized */ 247 assert(type.norm); 248 249 /* 250 * Compute src/dst factors. 251 */ 252 253 bld.factor[0][0][i] = src[i]; 254 bld.factor[0][1][i] = lp_build_blend_soa_factor(&bld, src_factor, i); 255 bld.factor[1][0][i] = dst[i]; 256 bld.factor[1][1][i] = lp_build_blend_soa_factor(&bld, dst_factor, i); 257 258 /* 259 * Compute src/dst terms 260 */ 261 262 for(k = 0; k < 2; ++k) { 263 /* See if this multiplication has been previously computed */ 264 for(j = 0; j < i; ++j) { 265 if((bld.factor[k][0][j] == bld.factor[k][0][i] && 266 bld.factor[k][1][j] == bld.factor[k][1][i]) || 267 (bld.factor[k][0][j] == bld.factor[k][1][i] && 268 bld.factor[k][1][j] == bld.factor[k][0][i])) 269 break; 270 } 271 272 if(j < i) 273 bld.term[k][i] = bld.term[k][j]; 274 else 275 bld.term[k][i] = lp_build_mul(&bld.base, bld.factor[k][0][i], bld.factor[k][1][i]); 276 277 if (src_factor == PIPE_BLENDFACTOR_ZERO && 278 (dst_factor == PIPE_BLENDFACTOR_DST_ALPHA || 279 dst_factor == PIPE_BLENDFACTOR_INV_DST_ALPHA)) { 280 /* XXX special case these combos to work around an apparent 281 * bug in LLVM. 282 * This hack disables the check for multiplication by zero 283 * in lp_bld_mul(). When we optimize away the 284 * multiplication, something goes wrong during code 285 * generation and we segfault at runtime. 286 */ 287 LLVMValueRef zeroSave = bld.base.zero; 288 bld.base.zero = NULL; 289 bld.term[k][i] = lp_build_mul(&bld.base, bld.factor[k][0][i], 290 bld.factor[k][1][i]); 291 bld.base.zero = zeroSave; 292 } 293 } 294 295 /* 296 * Combine terms 297 */ 298 299 /* See if this function has been previously applied */ 300 for(j = 0; j < i; ++j) { 301 unsigned prev_func = j < 3 ? blend->rt[rt].rgb_func : blend->rt[rt].alpha_func; 302 unsigned func_reverse = lp_build_blend_func_reverse(func, prev_func); 303 304 if((!func_reverse && 305 bld.term[0][j] == bld.term[0][i] && 306 bld.term[1][j] == bld.term[1][i]) || 307 ((func_commutative || func_reverse) && 308 bld.term[0][j] == bld.term[1][i] && 309 bld.term[1][j] == bld.term[0][i])) 310 break; 311 } 312 313 if(j < i) 314 res[i] = res[j]; 315 else 316 res[i] = lp_build_blend_func(&bld.base, func, bld.term[0][i], bld.term[1][i]); 317 } 318 else { 319 res[i] = src[i]; 320 } 321 } 322 else { 323 res[i] = dst[i]; 324 } 325 } 326} 327