src/gallium/drivers/llvmpipe/lp_bld_blend_aos.c

   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 -- AoS layout.
  32  *
  33  * AoS blending is in general much slower than SoA, but there are some cases
  34  * where it might be faster. In particular, if a pixel is rendered only once
  35  * then the overhead of tiling and untiling will dominate over the speedup that
  36  * SoA gives. So we might want to detect such cases and fallback to AoS in the
  37  * future, but for now this function is here for historical/benchmarking
  38  * purposes.
  39  *
  40  * Run lp_blend_test after any change to this file.
  41  *
  42  * @author Jose Fonseca <jfonseca@vmware.com>
  43  */
  44
  45
  46 #include "pipe/p_state.h"
  47 #include "util/u_debug.h"
  48
  49 #include "gallivm/lp_bld_type.h"
  50 #include "gallivm/lp_bld_const.h"
  51 #include "gallivm/lp_bld_arit.h"
  52 #include "gallivm/lp_bld_logic.h"
  53 #include "gallivm/lp_bld_swizzle.h"
  54 #include "gallivm/lp_bld_debug.h"
  55
  56 #include "lp_bld_blend.h"
  57
  58
  59 /**
  60  * We may the same values several times, so we keep them here to avoid
  61  * recomputing them. Also reusing the values allows us to do simplifications
  62  * that LLVM optimization passes wouldn't normally be able to do.
  63  */
  64 struct lp_build_blend_aos_context
  65 {
  66    struct lp_build_context base;
  67
  68    LLVMValueRef src;
  69    LLVMValueRef dst;
  70    LLVMValueRef const_;
  71
  72    LLVMValueRef inv_src;
  73    LLVMValueRef inv_dst;
  74    LLVMValueRef inv_const;
  75    LLVMValueRef saturate;
  76
  77    LLVMValueRef rgb_src_factor;
  78    LLVMValueRef alpha_src_factor;
  79    LLVMValueRef rgb_dst_factor;
  80    LLVMValueRef alpha_dst_factor;
  81 };
  82
  83
  84 static LLVMValueRef
  85 lp_build_blend_factor_unswizzled(struct lp_build_blend_aos_context *bld,
  86                                  unsigned factor,
  87                                  boolean alpha)
  88 {
  89    switch (factor) {
  90    case PIPE_BLENDFACTOR_ZERO:
  91       return bld->base.zero;
  92    case PIPE_BLENDFACTOR_ONE:
  93       return bld->base.one;
  94    case PIPE_BLENDFACTOR_SRC_COLOR:
  95    case PIPE_BLENDFACTOR_SRC_ALPHA:
  96       return bld->src;
  97    case PIPE_BLENDFACTOR_DST_COLOR:
  98    case PIPE_BLENDFACTOR_DST_ALPHA:
  99       return bld->dst;
 100    case PIPE_BLENDFACTOR_SRC_ALPHA_SATURATE:
 101       if(alpha)
 102          return bld->base.one;
 103       else {
 104          if(!bld->inv_dst)
 105             bld->inv_dst = lp_build_comp(&bld->base, bld->dst);
 106          if(!bld->saturate)
 107             bld->saturate = lp_build_min(&bld->base, bld->src, bld->inv_dst);
 108          return bld->saturate;
 109       }
 110    case PIPE_BLENDFACTOR_CONST_COLOR:
 111    case PIPE_BLENDFACTOR_CONST_ALPHA:
 112       return bld->const_;
 113    case PIPE_BLENDFACTOR_SRC1_COLOR:
 114    case PIPE_BLENDFACTOR_SRC1_ALPHA:
 115       /* TODO */
 116       assert(0);
 117       return bld->base.zero;
 118    case PIPE_BLENDFACTOR_INV_SRC_COLOR:
 119    case PIPE_BLENDFACTOR_INV_SRC_ALPHA:
 120       if(!bld->inv_src)
 121          bld->inv_src = lp_build_comp(&bld->base, bld->src);
 122       return bld->inv_src;
 123    case PIPE_BLENDFACTOR_INV_DST_COLOR:
 124    case PIPE_BLENDFACTOR_INV_DST_ALPHA:
 125       if(!bld->inv_dst)
 126          bld->inv_dst = lp_build_comp(&bld->base, bld->dst);
 127       return bld->inv_dst;
 128    case PIPE_BLENDFACTOR_INV_CONST_COLOR:
 129    case PIPE_BLENDFACTOR_INV_CONST_ALPHA:
 130       if(!bld->inv_const)
 131          bld->inv_const = lp_build_comp(&bld->base, bld->const_);
 132       return bld->inv_const;
 133    case PIPE_BLENDFACTOR_INV_SRC1_COLOR:
 134    case PIPE_BLENDFACTOR_INV_SRC1_ALPHA:
 135       /* TODO */
 136       assert(0);
 137       return bld->base.zero;
 138    default:
 139       assert(0);
 140       return bld->base.zero;
 141    }
 142 }
 143
 144
 145 enum lp_build_blend_swizzle {
 146    LP_BUILD_BLEND_SWIZZLE_RGBA = 0,
 147    LP_BUILD_BLEND_SWIZZLE_AAAA = 1
 148 };
 149
 150
 151 /**
 152  * How should we shuffle the base factor.
 153  */
 154 static enum lp_build_blend_swizzle
 155 lp_build_blend_factor_swizzle(unsigned factor)
 156 {
 157    switch (factor) {
 158    case PIPE_BLENDFACTOR_ONE:
 159    case PIPE_BLENDFACTOR_ZERO:
 160    case PIPE_BLENDFACTOR_SRC_COLOR:
 161    case PIPE_BLENDFACTOR_DST_COLOR:
 162    case PIPE_BLENDFACTOR_CONST_COLOR:
 163    case PIPE_BLENDFACTOR_SRC1_COLOR:
 164    case PIPE_BLENDFACTOR_INV_SRC_COLOR:
 165    case PIPE_BLENDFACTOR_INV_DST_COLOR:
 166    case PIPE_BLENDFACTOR_INV_CONST_COLOR:
 167    case PIPE_BLENDFACTOR_INV_SRC1_COLOR:
 168       return LP_BUILD_BLEND_SWIZZLE_RGBA;
 169    case PIPE_BLENDFACTOR_SRC_ALPHA:
 170    case PIPE_BLENDFACTOR_DST_ALPHA:
 171    case PIPE_BLENDFACTOR_SRC_ALPHA_SATURATE:
 172    case PIPE_BLENDFACTOR_SRC1_ALPHA:
 173    case PIPE_BLENDFACTOR_CONST_ALPHA:
 174    case PIPE_BLENDFACTOR_INV_SRC_ALPHA:
 175    case PIPE_BLENDFACTOR_INV_DST_ALPHA:
 176    case PIPE_BLENDFACTOR_INV_CONST_ALPHA:
 177    case PIPE_BLENDFACTOR_INV_SRC1_ALPHA:
 178       return LP_BUILD_BLEND_SWIZZLE_AAAA;
 179    default:
 180       assert(0);
 181       return LP_BUILD_BLEND_SWIZZLE_RGBA;
 182    }
 183 }
 184
 185
 186 static LLVMValueRef
 187 lp_build_blend_swizzle(struct lp_build_blend_aos_context *bld,
 188                        LLVMValueRef rgb,
 189                        LLVMValueRef alpha,
 190                        enum lp_build_blend_swizzle rgb_swizzle,
 191                        unsigned alpha_swizzle)
 192 {
 193    LLVMValueRef swizzled_rgb;
 194
 195    switch (rgb_swizzle) {
 196    case LP_BUILD_BLEND_SWIZZLE_RGBA:
 197       swizzled_rgb = rgb;
 198       break;
 199    case LP_BUILD_BLEND_SWIZZLE_AAAA:
 200       swizzled_rgb = lp_build_swizzle_scalar_aos(&bld->base, rgb, alpha_swizzle);
 201       break;
 202    default:
 203       assert(0);
 204       swizzled_rgb = bld->base.undef;
 205    }
 206
 207    if (rgb != alpha) {
 208       swizzled_rgb = lp_build_select_aos(&bld->base, 1 << alpha_swizzle,
 209                                          alpha, swizzled_rgb);
 210    }
 211
 212    return swizzled_rgb;
 213 }
 214
 215
 216 /**
 217  * @sa http://www.opengl.org/sdk/docs/man/xhtml/glBlendFuncSeparate.xml
 218  */
 219 static LLVMValueRef
 220 lp_build_blend_factor(struct lp_build_blend_aos_context *bld,
 221                       LLVMValueRef factor1,
 222                       unsigned rgb_factor,
 223                       unsigned alpha_factor,
 224                       unsigned alpha_swizzle)
 225 {
 226    LLVMValueRef rgb_factor_;
 227    LLVMValueRef alpha_factor_;
 228    LLVMValueRef factor2;
 229    enum lp_build_blend_swizzle rgb_swizzle;
 230
 231    rgb_factor_   = lp_build_blend_factor_unswizzled(bld, rgb_factor,   FALSE);
 232    alpha_factor_ = lp_build_blend_factor_unswizzled(bld, alpha_factor, TRUE);
 233
 234    rgb_swizzle = lp_build_blend_factor_swizzle(rgb_factor);
 235
 236    factor2 = lp_build_blend_swizzle(bld, rgb_factor_, alpha_factor_, rgb_swizzle, alpha_swizzle);
 237
 238    return lp_build_mul(&bld->base, factor1, factor2);
 239 }
 240
 241
 242 /**
 243  * Is (a OP b) == (b OP a)?
 244  */
 245 boolean
 246 lp_build_blend_func_commutative(unsigned func)
 247 {
 248    switch (func) {
 249    case PIPE_BLEND_ADD:
 250    case PIPE_BLEND_MIN:
 251    case PIPE_BLEND_MAX:
 252       return TRUE;
 253    case PIPE_BLEND_SUBTRACT:
 254    case PIPE_BLEND_REVERSE_SUBTRACT:
 255       return FALSE;
 256    default:
 257       assert(0);
 258       return TRUE;
 259    }
 260 }
 261
 262
 263 boolean
 264 lp_build_blend_func_reverse(unsigned rgb_func, unsigned alpha_func)
 265 {
 266    if(rgb_func == alpha_func)
 267       return FALSE;
 268    if(rgb_func == PIPE_BLEND_SUBTRACT && alpha_func == PIPE_BLEND_REVERSE_SUBTRACT)
 269       return TRUE;
 270    if(rgb_func == PIPE_BLEND_REVERSE_SUBTRACT && alpha_func == PIPE_BLEND_SUBTRACT)
 271       return TRUE;
 272    return FALSE;
 273 }
 274
 275
 276 /**
 277  * @sa http://www.opengl.org/sdk/docs/man/xhtml/glBlendEquationSeparate.xml
 278  */
 279 LLVMValueRef
 280 lp_build_blend_func(struct lp_build_context *bld,
 281                     unsigned func,
 282                     LLVMValueRef term1,
 283                     LLVMValueRef term2)
 284 {
 285    switch (func) {
 286    case PIPE_BLEND_ADD:
 287       return lp_build_add(bld, term1, term2);
 288    case PIPE_BLEND_SUBTRACT:
 289       return lp_build_sub(bld, term1, term2);
 290    case PIPE_BLEND_REVERSE_SUBTRACT:
 291       return lp_build_sub(bld, term2, term1);
 292    case PIPE_BLEND_MIN:
 293       return lp_build_min(bld, term1, term2);
 294    case PIPE_BLEND_MAX:
 295       return lp_build_max(bld, term1, term2);
 296    default:
 297       assert(0);
 298       return bld->zero;
 299    }
 300 }
 301
 302
 303 LLVMValueRef
 304 lp_build_blend_aos(struct gallivm_state *gallivm,
 305                    const struct pipe_blend_state *blend,
 306                    struct lp_type type,
 307                    unsigned rt,
 308                    LLVMValueRef src,
 309                    LLVMValueRef dst,
 310                    LLVMValueRef const_,
 311                    unsigned alpha_swizzle)
 312 {
 313    struct lp_build_blend_aos_context bld;
 314    LLVMValueRef src_term;
 315    LLVMValueRef dst_term;
 316
 317    /* FIXME: color masking not implemented yet */
 318    assert(blend->rt[rt].colormask == 0xf);
 319
 320    if(!blend->rt[rt].blend_enable)
 321       return src;
 322
 323    /* Setup build context */
 324    memset(&bld, 0, sizeof bld);
 325    lp_build_context_init(&bld.base, gallivm, type);
 326    bld.src = src;
 327    bld.dst = dst;
 328    bld.const_ = const_;
 329
 330    /* TODO: There are still a few optimization opportunities here. For certain
 331     * combinations it is possible to reorder the operations and therefore saving
 332     * some instructions. */
 333
 334    src_term = lp_build_blend_factor(&bld, src, blend->rt[rt].rgb_src_factor,
 335                                     blend->rt[rt].alpha_src_factor, alpha_swizzle);
 336    dst_term = lp_build_blend_factor(&bld, dst, blend->rt[rt].rgb_dst_factor,
 337                                     blend->rt[rt].alpha_dst_factor, alpha_swizzle);
 338
 339    lp_build_name(src_term, "src_term");
 340    lp_build_name(dst_term, "dst_term");
 341
 342    if(blend->rt[rt].rgb_func == blend->rt[rt].alpha_func) {
 343       return lp_build_blend_func(&bld.base, blend->rt[rt].rgb_func, src_term, dst_term);
 344    }
 345    else {
 346       /* Seperate RGB / A functions */
 347
 348       LLVMValueRef rgb;
 349       LLVMValueRef alpha;
 350
 351       rgb   = lp_build_blend_func(&bld.base, blend->rt[rt].rgb_func,   src_term, dst_term);
 352       alpha = lp_build_blend_func(&bld.base, blend->rt[rt].alpha_func, src_term, dst_term);
 353
 354       return lp_build_blend_swizzle(&bld, rgb, alpha, LP_BUILD_BLEND_SWIZZLE_RGBA, alpha_swizzle);
 355    }
 356 }