| // Copyright (c) 2018 Google Inc. |
| // |
| // Licensed under the Apache License, Version 2.0 (the "License"); |
| // you may not use this file except in compliance with the License. |
| // You may obtain a copy of the License at |
| // |
| // http://www.apache.org/licenses/LICENSE-2.0 |
| // |
| // Unless required by applicable law or agreed to in writing, software |
| // distributed under the License is distributed on an "AS IS" BASIS, |
| // WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| // See the License for the specific language governing permissions and |
| // limitations under the License. |
| |
| #include "source/reduce/remove_unreferenced_instruction_reduction_opportunity_finder.h" |
| |
| #include "source/opcode.h" |
| #include "source/opt/instruction.h" |
| #include "source/reduce/remove_instruction_reduction_opportunity.h" |
| |
| namespace spvtools { |
| namespace reduce { |
| |
| RemoveUnreferencedInstructionReductionOpportunityFinder:: |
| RemoveUnreferencedInstructionReductionOpportunityFinder( |
| bool remove_constants_and_undefs) |
| : remove_constants_and_undefs_(remove_constants_and_undefs) {} |
| |
| std::vector<std::unique_ptr<ReductionOpportunity>> |
| RemoveUnreferencedInstructionReductionOpportunityFinder:: |
| GetAvailableOpportunities(opt::IRContext* context) const { |
| std::vector<std::unique_ptr<ReductionOpportunity>> result; |
| |
| for (auto& inst : context->module()->debugs1()) { |
| if (context->get_def_use_mgr()->NumUses(&inst) > 0) { |
| continue; |
| } |
| result.push_back(MakeUnique<RemoveInstructionReductionOpportunity>(&inst)); |
| } |
| |
| for (auto& inst : context->module()->debugs2()) { |
| if (context->get_def_use_mgr()->NumUses(&inst) > 0) { |
| continue; |
| } |
| result.push_back(MakeUnique<RemoveInstructionReductionOpportunity>(&inst)); |
| } |
| |
| for (auto& inst : context->module()->debugs3()) { |
| if (context->get_def_use_mgr()->NumUses(&inst) > 0) { |
| continue; |
| } |
| result.push_back(MakeUnique<RemoveInstructionReductionOpportunity>(&inst)); |
| } |
| |
| for (auto& inst : context->module()->ext_inst_debuginfo()) { |
| if (context->get_def_use_mgr()->NumUses(&inst) > 0) { |
| continue; |
| } |
| result.push_back(MakeUnique<RemoveInstructionReductionOpportunity>(&inst)); |
| } |
| |
| for (auto& inst : context->module()->types_values()) { |
| if (context->get_def_use_mgr()->NumUsers(&inst) > 0) { |
| continue; |
| } |
| if (!remove_constants_and_undefs_ && |
| spvOpcodeIsConstantOrUndef(inst.opcode())) { |
| continue; |
| } |
| result.push_back(MakeUnique<RemoveInstructionReductionOpportunity>(&inst)); |
| } |
| |
| for (auto& inst : context->module()->annotations()) { |
| if (context->get_def_use_mgr()->NumUsers(&inst) > 0) { |
| continue; |
| } |
| |
| uint32_t decoration = SpvDecorationMax; |
| switch (inst.opcode()) { |
| case SpvOpDecorate: |
| case SpvOpDecorateId: |
| case SpvOpDecorateString: |
| decoration = inst.GetSingleWordInOperand(1u); |
| break; |
| case SpvOpMemberDecorate: |
| case SpvOpMemberDecorateString: |
| decoration = inst.GetSingleWordInOperand(2u); |
| break; |
| default: |
| break; |
| } |
| |
| // We conservatively only remove specific decorations that we believe will |
| // not change the shader interface, will not make the shader invalid, will |
| // actually be found in practice, etc. |
| |
| switch (decoration) { |
| case SpvDecorationRelaxedPrecision: |
| case SpvDecorationNoSignedWrap: |
| case SpvDecorationNoContraction: |
| case SpvDecorationNoUnsignedWrap: |
| case SpvDecorationUserSemantic: |
| break; |
| default: |
| // Give up. |
| continue; |
| } |
| |
| result.push_back(MakeUnique<RemoveInstructionReductionOpportunity>(&inst)); |
| } |
| |
| for (auto& function : *context->module()) { |
| for (auto& block : function) { |
| for (auto& inst : block) { |
| if (context->get_def_use_mgr()->NumUses(&inst) > 0) { |
| continue; |
| } |
| if (!remove_constants_and_undefs_ && |
| spvOpcodeIsConstantOrUndef(inst.opcode())) { |
| continue; |
| } |
| if (spvOpcodeIsBlockTerminator(inst.opcode()) || |
| inst.opcode() == SpvOpSelectionMerge || |
| inst.opcode() == SpvOpLoopMerge) { |
| // In this reduction pass we do not want to affect static |
| // control flow. |
| continue; |
| } |
| // Given that we're in a block, we should only get here if |
| // the instruction is not directly related to control flow; |
| // i.e., it's some straightforward instruction with an |
| // unused result, like an arithmetic operation or function |
| // call. |
| result.push_back( |
| MakeUnique<RemoveInstructionReductionOpportunity>(&inst)); |
| } |
| } |
| } |
| return result; |
| } |
| |
| std::string RemoveUnreferencedInstructionReductionOpportunityFinder::GetName() |
| const { |
| return "RemoveUnreferencedInstructionReductionOpportunityFinder"; |
| } |
| |
| } // namespace reduce |
| } // namespace spvtools |