src/gallium/drivers/r300/compiler/radeon_pair_dead_sources.c

   1 /*
   2  * Copyright 2011 Tom Stellard <tstellar@gmail.com>
   3  *
   4  * All Rights Reserved.
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining
   7  * a 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, sublicense, 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
  16  * portions of the Software.
  17  *
  18  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  19  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  20  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
  21  * IN NO EVENT SHALL THE COPYRIGHT OWNER(S) AND/OR ITS SUPPLIERS BE
  22  * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
  23  * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
  24  * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
  25  *
  26  */
  27
  28 #include "radeon_compiler.h"
  29 #include "radeon_compiler_util.h"
  30 #include "radeon_opcodes.h"
  31 #include "radeon_program_pair.h"
  32
  33 static void mark_used_presub(struct rc_pair_sub_instruction * sub)
  34 {
  35         if (sub->Src[RC_PAIR_PRESUB_SRC].Used) {
  36                 unsigned int presub_reg_count = rc_presubtract_src_reg_count(
  37                                         sub->Src[RC_PAIR_PRESUB_SRC].Index);
  38                 unsigned int i;
  39                 for (i = 0; i < presub_reg_count; i++) {
  40                         sub->Src[i].Used = 1;
  41                 }
  42         }
  43 }
  44
  45 static void mark_used(
  46         struct rc_instruction * inst,
  47         struct rc_pair_sub_instruction * sub)
  48 {
  49         unsigned int i;
  50         const struct rc_opcode_info * info = rc_get_opcode_info(sub->Opcode);
  51         for (i = 0; i < info->NumSrcRegs; i++) {
  52                 unsigned int src_type = rc_source_type_swz(sub->Arg[i].Swizzle);
  53                 if (src_type & RC_SOURCE_RGB) {
  54                         inst->U.P.RGB.Src[sub->Arg[i].Source].Used = 1;
  55                 }
  56
  57                 if (src_type & RC_SOURCE_ALPHA) {
  58                         inst->U.P.Alpha.Src[sub->Arg[i].Source].Used = 1;
  59                 }
  60         }
  61 }
  62
  63 /**
  64  * This pass finds sources that are not used by their instruction and marks
  65  * them as unused.
  66  */
  67 void rc_pair_remove_dead_sources(struct radeon_compiler * c, void *user)
  68 {
  69         struct rc_instruction * inst;
  70         for (inst = c->Program.Instructions.Next;
  71                                         inst != &c->Program.Instructions;
  72                                         inst = inst->Next) {
  73                 unsigned int i;
  74                 if (inst->Type == RC_INSTRUCTION_NORMAL)
  75                         continue;
  76
  77                 /* Mark all sources as unused */
  78                 for (i = 0; i < 4; i++) {
  79                         inst->U.P.RGB.Src[i].Used = 0;
  80                         inst->U.P.Alpha.Src[i].Used = 0;
  81                 }
  82                 mark_used(inst, &inst->U.P.RGB);
  83                 mark_used(inst, &inst->U.P.Alpha);
  84
  85                 mark_used_presub(&inst->U.P.RGB);
  86                 mark_used_presub(&inst->U.P.Alpha);
  87         }
  88 }