| // Copyright (c) 2017 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/opt/scalar_replacement_pass.h" |
| |
| #include <algorithm> |
| #include <queue> |
| #include <tuple> |
| #include <utility> |
| |
| #include "source/enum_string_mapping.h" |
| #include "source/extensions.h" |
| #include "source/opt/reflect.h" |
| #include "source/opt/types.h" |
| #include "source/util/make_unique.h" |
| |
| static const uint32_t kDebugValueOperandValueIndex = 5; |
| static const uint32_t kDebugValueOperandExpressionIndex = 6; |
| static const uint32_t kDebugDeclareOperandVariableIndex = 5; |
| |
| namespace spvtools { |
| namespace opt { |
| |
| Pass::Status ScalarReplacementPass::Process() { |
| Status status = Status::SuccessWithoutChange; |
| for (auto& f : *get_module()) { |
| if (f.IsDeclaration()) { |
| continue; |
| } |
| |
| Status functionStatus = ProcessFunction(&f); |
| if (functionStatus == Status::Failure) |
| return functionStatus; |
| else if (functionStatus == Status::SuccessWithChange) |
| status = functionStatus; |
| } |
| |
| return status; |
| } |
| |
| Pass::Status ScalarReplacementPass::ProcessFunction(Function* function) { |
| std::queue<Instruction*> worklist; |
| BasicBlock& entry = *function->begin(); |
| for (auto iter = entry.begin(); iter != entry.end(); ++iter) { |
| // Function storage class OpVariables must appear as the first instructions |
| // of the entry block. |
| if (iter->opcode() != SpvOpVariable) break; |
| |
| Instruction* varInst = &*iter; |
| if (CanReplaceVariable(varInst)) { |
| worklist.push(varInst); |
| } |
| } |
| |
| Status status = Status::SuccessWithoutChange; |
| while (!worklist.empty()) { |
| Instruction* varInst = worklist.front(); |
| worklist.pop(); |
| |
| Status var_status = ReplaceVariable(varInst, &worklist); |
| if (var_status == Status::Failure) |
| return var_status; |
| else if (var_status == Status::SuccessWithChange) |
| status = var_status; |
| } |
| |
| return status; |
| } |
| |
| Pass::Status ScalarReplacementPass::ReplaceVariable( |
| Instruction* inst, std::queue<Instruction*>* worklist) { |
| std::vector<Instruction*> replacements; |
| if (!CreateReplacementVariables(inst, &replacements)) { |
| return Status::Failure; |
| } |
| |
| std::vector<Instruction*> dead; |
| bool replaced_all_uses = get_def_use_mgr()->WhileEachUser( |
| inst, [this, &replacements, &dead](Instruction* user) { |
| if (user->GetCommonDebugOpcode() == CommonDebugInfoDebugDeclare) { |
| if (ReplaceWholeDebugDeclare(user, replacements)) { |
| dead.push_back(user); |
| return true; |
| } |
| return false; |
| } |
| if (user->GetCommonDebugOpcode() == CommonDebugInfoDebugValue) { |
| if (ReplaceWholeDebugValue(user, replacements)) { |
| dead.push_back(user); |
| return true; |
| } |
| return false; |
| } |
| if (!IsAnnotationInst(user->opcode())) { |
| switch (user->opcode()) { |
| case SpvOpLoad: |
| if (ReplaceWholeLoad(user, replacements)) { |
| dead.push_back(user); |
| } else { |
| return false; |
| } |
| break; |
| case SpvOpStore: |
| if (ReplaceWholeStore(user, replacements)) { |
| dead.push_back(user); |
| } else { |
| return false; |
| } |
| break; |
| case SpvOpAccessChain: |
| case SpvOpInBoundsAccessChain: |
| if (ReplaceAccessChain(user, replacements)) |
| dead.push_back(user); |
| else |
| return false; |
| break; |
| case SpvOpName: |
| case SpvOpMemberName: |
| break; |
| default: |
| assert(false && "Unexpected opcode"); |
| break; |
| } |
| } |
| return true; |
| }); |
| |
| if (replaced_all_uses) { |
| dead.push_back(inst); |
| } else { |
| return Status::Failure; |
| } |
| |
| // If there are no dead instructions to clean up, return with no changes. |
| if (dead.empty()) return Status::SuccessWithoutChange; |
| |
| // Clean up some dead code. |
| while (!dead.empty()) { |
| Instruction* toKill = dead.back(); |
| dead.pop_back(); |
| context()->KillInst(toKill); |
| } |
| |
| // Attempt to further scalarize. |
| for (auto var : replacements) { |
| if (var->opcode() == SpvOpVariable) { |
| if (get_def_use_mgr()->NumUsers(var) == 0) { |
| context()->KillInst(var); |
| } else if (CanReplaceVariable(var)) { |
| worklist->push(var); |
| } |
| } |
| } |
| |
| return Status::SuccessWithChange; |
| } |
| |
| bool ScalarReplacementPass::ReplaceWholeDebugDeclare( |
| Instruction* dbg_decl, const std::vector<Instruction*>& replacements) { |
| // Insert Deref operation to the front of the operation list of |dbg_decl|. |
| Instruction* dbg_expr = context()->get_def_use_mgr()->GetDef( |
| dbg_decl->GetSingleWordOperand(kDebugValueOperandExpressionIndex)); |
| auto* deref_expr = |
| context()->get_debug_info_mgr()->DerefDebugExpression(dbg_expr); |
| |
| // Add DebugValue instruction with Indexes operand and Deref operation. |
| int32_t idx = 0; |
| for (const auto* var : replacements) { |
| Instruction* insert_before = var->NextNode(); |
| while (insert_before->opcode() == SpvOpVariable) |
| insert_before = insert_before->NextNode(); |
| assert(insert_before != nullptr && "unexpected end of list"); |
| Instruction* added_dbg_value = |
| context()->get_debug_info_mgr()->AddDebugValueForDecl( |
| dbg_decl, /*value_id=*/var->result_id(), |
| /*insert_before=*/insert_before, /*scope_and_line=*/dbg_decl); |
| |
| if (added_dbg_value == nullptr) return false; |
| added_dbg_value->AddOperand( |
| {SPV_OPERAND_TYPE_ID, |
| {context()->get_constant_mgr()->GetSIntConst(idx)}}); |
| added_dbg_value->SetOperand(kDebugValueOperandExpressionIndex, |
| {deref_expr->result_id()}); |
| if (context()->AreAnalysesValid(IRContext::Analysis::kAnalysisDefUse)) { |
| context()->get_def_use_mgr()->AnalyzeInstUse(added_dbg_value); |
| } |
| ++idx; |
| } |
| return true; |
| } |
| |
| bool ScalarReplacementPass::ReplaceWholeDebugValue( |
| Instruction* dbg_value, const std::vector<Instruction*>& replacements) { |
| int32_t idx = 0; |
| BasicBlock* block = context()->get_instr_block(dbg_value); |
| for (auto var : replacements) { |
| // Clone the DebugValue. |
| std::unique_ptr<Instruction> new_dbg_value(dbg_value->Clone(context())); |
| uint32_t new_id = TakeNextId(); |
| if (new_id == 0) return false; |
| new_dbg_value->SetResultId(new_id); |
| // Update 'Value' operand to the |replacements|. |
| new_dbg_value->SetOperand(kDebugValueOperandValueIndex, {var->result_id()}); |
| // Append 'Indexes' operand. |
| new_dbg_value->AddOperand( |
| {SPV_OPERAND_TYPE_ID, |
| {context()->get_constant_mgr()->GetSIntConst(idx)}}); |
| // Insert the new DebugValue to the basic block. |
| auto* added_instr = dbg_value->InsertBefore(std::move(new_dbg_value)); |
| get_def_use_mgr()->AnalyzeInstDefUse(added_instr); |
| context()->set_instr_block(added_instr, block); |
| ++idx; |
| } |
| return true; |
| } |
| |
| bool ScalarReplacementPass::ReplaceWholeLoad( |
| Instruction* load, const std::vector<Instruction*>& replacements) { |
| // Replaces the load of the entire composite with a load from each replacement |
| // variable followed by a composite construction. |
| BasicBlock* block = context()->get_instr_block(load); |
| std::vector<Instruction*> loads; |
| loads.reserve(replacements.size()); |
| BasicBlock::iterator where(load); |
| for (auto var : replacements) { |
| // Create a load of each replacement variable. |
| if (var->opcode() != SpvOpVariable) { |
| loads.push_back(var); |
| continue; |
| } |
| |
| Instruction* type = GetStorageType(var); |
| uint32_t loadId = TakeNextId(); |
| if (loadId == 0) { |
| return false; |
| } |
| std::unique_ptr<Instruction> newLoad( |
| new Instruction(context(), SpvOpLoad, type->result_id(), loadId, |
| std::initializer_list<Operand>{ |
| {SPV_OPERAND_TYPE_ID, {var->result_id()}}})); |
| // Copy memory access attributes which start at index 1. Index 0 is the |
| // pointer to load. |
| for (uint32_t i = 1; i < load->NumInOperands(); ++i) { |
| Operand copy(load->GetInOperand(i)); |
| newLoad->AddOperand(std::move(copy)); |
| } |
| where = where.InsertBefore(std::move(newLoad)); |
| get_def_use_mgr()->AnalyzeInstDefUse(&*where); |
| context()->set_instr_block(&*where, block); |
| where->UpdateDebugInfoFrom(load); |
| loads.push_back(&*where); |
| } |
| |
| // Construct a new composite. |
| uint32_t compositeId = TakeNextId(); |
| if (compositeId == 0) { |
| return false; |
| } |
| where = load; |
| std::unique_ptr<Instruction> compositeConstruct(new Instruction( |
| context(), SpvOpCompositeConstruct, load->type_id(), compositeId, {})); |
| for (auto l : loads) { |
| Operand op(SPV_OPERAND_TYPE_ID, |
| std::initializer_list<uint32_t>{l->result_id()}); |
| compositeConstruct->AddOperand(std::move(op)); |
| } |
| where = where.InsertBefore(std::move(compositeConstruct)); |
| get_def_use_mgr()->AnalyzeInstDefUse(&*where); |
| where->UpdateDebugInfoFrom(load); |
| context()->set_instr_block(&*where, block); |
| context()->ReplaceAllUsesWith(load->result_id(), compositeId); |
| return true; |
| } |
| |
| bool ScalarReplacementPass::ReplaceWholeStore( |
| Instruction* store, const std::vector<Instruction*>& replacements) { |
| // Replaces a store to the whole composite with a series of extract and stores |
| // to each element. |
| uint32_t storeInput = store->GetSingleWordInOperand(1u); |
| BasicBlock* block = context()->get_instr_block(store); |
| BasicBlock::iterator where(store); |
| uint32_t elementIndex = 0; |
| for (auto var : replacements) { |
| // Create the extract. |
| if (var->opcode() != SpvOpVariable) { |
| elementIndex++; |
| continue; |
| } |
| |
| Instruction* type = GetStorageType(var); |
| uint32_t extractId = TakeNextId(); |
| if (extractId == 0) { |
| return false; |
| } |
| std::unique_ptr<Instruction> extract(new Instruction( |
| context(), SpvOpCompositeExtract, type->result_id(), extractId, |
| std::initializer_list<Operand>{ |
| {SPV_OPERAND_TYPE_ID, {storeInput}}, |
| {SPV_OPERAND_TYPE_LITERAL_INTEGER, {elementIndex++}}})); |
| auto iter = where.InsertBefore(std::move(extract)); |
| iter->UpdateDebugInfoFrom(store); |
| get_def_use_mgr()->AnalyzeInstDefUse(&*iter); |
| context()->set_instr_block(&*iter, block); |
| |
| // Create the store. |
| std::unique_ptr<Instruction> newStore( |
| new Instruction(context(), SpvOpStore, 0, 0, |
| std::initializer_list<Operand>{ |
| {SPV_OPERAND_TYPE_ID, {var->result_id()}}, |
| {SPV_OPERAND_TYPE_ID, {extractId}}})); |
| // Copy memory access attributes which start at index 2. Index 0 is the |
| // pointer and index 1 is the data. |
| for (uint32_t i = 2; i < store->NumInOperands(); ++i) { |
| Operand copy(store->GetInOperand(i)); |
| newStore->AddOperand(std::move(copy)); |
| } |
| iter = where.InsertBefore(std::move(newStore)); |
| iter->UpdateDebugInfoFrom(store); |
| get_def_use_mgr()->AnalyzeInstDefUse(&*iter); |
| context()->set_instr_block(&*iter, block); |
| } |
| return true; |
| } |
| |
| bool ScalarReplacementPass::ReplaceAccessChain( |
| Instruction* chain, const std::vector<Instruction*>& replacements) { |
| // Replaces the access chain with either another access chain (with one fewer |
| // indexes) or a direct use of the replacement variable. |
| uint32_t indexId = chain->GetSingleWordInOperand(1u); |
| const Instruction* index = get_def_use_mgr()->GetDef(indexId); |
| int64_t indexValue = context() |
| ->get_constant_mgr() |
| ->GetConstantFromInst(index) |
| ->GetSignExtendedValue(); |
| if (indexValue < 0 || |
| indexValue >= static_cast<int64_t>(replacements.size())) { |
| // Out of bounds access, this is illegal IR. Notice that OpAccessChain |
| // indexing is 0-based, so we should also reject index == size-of-array. |
| return false; |
| } else { |
| const Instruction* var = replacements[static_cast<size_t>(indexValue)]; |
| if (chain->NumInOperands() > 2) { |
| // Replace input access chain with another access chain. |
| BasicBlock::iterator chainIter(chain); |
| uint32_t replacementId = TakeNextId(); |
| if (replacementId == 0) { |
| return false; |
| } |
| std::unique_ptr<Instruction> replacementChain(new Instruction( |
| context(), chain->opcode(), chain->type_id(), replacementId, |
| std::initializer_list<Operand>{ |
| {SPV_OPERAND_TYPE_ID, {var->result_id()}}})); |
| // Add the remaining indexes. |
| for (uint32_t i = 2; i < chain->NumInOperands(); ++i) { |
| Operand copy(chain->GetInOperand(i)); |
| replacementChain->AddOperand(std::move(copy)); |
| } |
| replacementChain->UpdateDebugInfoFrom(chain); |
| auto iter = chainIter.InsertBefore(std::move(replacementChain)); |
| get_def_use_mgr()->AnalyzeInstDefUse(&*iter); |
| context()->set_instr_block(&*iter, context()->get_instr_block(chain)); |
| context()->ReplaceAllUsesWith(chain->result_id(), replacementId); |
| } else { |
| // Replace with a use of the variable. |
| context()->ReplaceAllUsesWith(chain->result_id(), var->result_id()); |
| } |
| } |
| |
| return true; |
| } |
| |
| bool ScalarReplacementPass::CreateReplacementVariables( |
| Instruction* inst, std::vector<Instruction*>* replacements) { |
| Instruction* type = GetStorageType(inst); |
| |
| std::unique_ptr<std::unordered_set<int64_t>> components_used = |
| GetUsedComponents(inst); |
| |
| uint32_t elem = 0; |
| switch (type->opcode()) { |
| case SpvOpTypeStruct: |
| type->ForEachInOperand( |
| [this, inst, &elem, replacements, &components_used](uint32_t* id) { |
| if (!components_used || components_used->count(elem)) { |
| CreateVariable(*id, inst, elem, replacements); |
| } else { |
| replacements->push_back(CreateNullConstant(*id)); |
| } |
| elem++; |
| }); |
| break; |
| case SpvOpTypeArray: |
| for (uint32_t i = 0; i != GetArrayLength(type); ++i) { |
| if (!components_used || components_used->count(i)) { |
| CreateVariable(type->GetSingleWordInOperand(0u), inst, i, |
| replacements); |
| } else { |
| replacements->push_back( |
| CreateNullConstant(type->GetSingleWordInOperand(0u))); |
| } |
| } |
| break; |
| |
| case SpvOpTypeMatrix: |
| case SpvOpTypeVector: |
| for (uint32_t i = 0; i != GetNumElements(type); ++i) { |
| CreateVariable(type->GetSingleWordInOperand(0u), inst, i, replacements); |
| } |
| break; |
| |
| default: |
| assert(false && "Unexpected type."); |
| break; |
| } |
| |
| TransferAnnotations(inst, replacements); |
| return std::find(replacements->begin(), replacements->end(), nullptr) == |
| replacements->end(); |
| } |
| |
| void ScalarReplacementPass::TransferAnnotations( |
| const Instruction* source, std::vector<Instruction*>* replacements) { |
| // Only transfer invariant and restrict decorations on the variable. There are |
| // no type or member decorations that are necessary to transfer. |
| for (auto inst : |
| get_decoration_mgr()->GetDecorationsFor(source->result_id(), false)) { |
| assert(inst->opcode() == SpvOpDecorate); |
| uint32_t decoration = inst->GetSingleWordInOperand(1u); |
| if (decoration == SpvDecorationInvariant || |
| decoration == SpvDecorationRestrict) { |
| for (auto var : *replacements) { |
| if (var == nullptr) { |
| continue; |
| } |
| |
| std::unique_ptr<Instruction> annotation( |
| new Instruction(context(), SpvOpDecorate, 0, 0, |
| std::initializer_list<Operand>{ |
| {SPV_OPERAND_TYPE_ID, {var->result_id()}}, |
| {SPV_OPERAND_TYPE_DECORATION, {decoration}}})); |
| for (uint32_t i = 2; i < inst->NumInOperands(); ++i) { |
| Operand copy(inst->GetInOperand(i)); |
| annotation->AddOperand(std::move(copy)); |
| } |
| context()->AddAnnotationInst(std::move(annotation)); |
| get_def_use_mgr()->AnalyzeInstUse(&*--context()->annotation_end()); |
| } |
| } |
| } |
| } |
| |
| void ScalarReplacementPass::CreateVariable( |
| uint32_t typeId, Instruction* varInst, uint32_t index, |
| std::vector<Instruction*>* replacements) { |
| uint32_t ptrId = GetOrCreatePointerType(typeId); |
| uint32_t id = TakeNextId(); |
| |
| if (id == 0) { |
| replacements->push_back(nullptr); |
| } |
| |
| std::unique_ptr<Instruction> variable(new Instruction( |
| context(), SpvOpVariable, ptrId, id, |
| std::initializer_list<Operand>{ |
| {SPV_OPERAND_TYPE_STORAGE_CLASS, {SpvStorageClassFunction}}})); |
| |
| BasicBlock* block = context()->get_instr_block(varInst); |
| block->begin().InsertBefore(std::move(variable)); |
| Instruction* inst = &*block->begin(); |
| |
| // If varInst was initialized, make sure to initialize its replacement. |
| GetOrCreateInitialValue(varInst, index, inst); |
| get_def_use_mgr()->AnalyzeInstDefUse(inst); |
| context()->set_instr_block(inst, block); |
| |
| // Copy decorations from the member to the new variable. |
| Instruction* typeInst = GetStorageType(varInst); |
| for (auto dec_inst : |
| get_decoration_mgr()->GetDecorationsFor(typeInst->result_id(), false)) { |
| uint32_t decoration; |
| if (dec_inst->opcode() != SpvOpMemberDecorate) { |
| continue; |
| } |
| |
| if (dec_inst->GetSingleWordInOperand(1) != index) { |
| continue; |
| } |
| |
| decoration = dec_inst->GetSingleWordInOperand(2u); |
| switch (decoration) { |
| case SpvDecorationRelaxedPrecision: { |
| std::unique_ptr<Instruction> new_dec_inst( |
| new Instruction(context(), SpvOpDecorate, 0, 0, {})); |
| new_dec_inst->AddOperand(Operand(SPV_OPERAND_TYPE_ID, {id})); |
| for (uint32_t i = 2; i < dec_inst->NumInOperandWords(); ++i) { |
| new_dec_inst->AddOperand(Operand(dec_inst->GetInOperand(i))); |
| } |
| context()->AddAnnotationInst(std::move(new_dec_inst)); |
| } break; |
| default: |
| break; |
| } |
| } |
| |
| // Update the DebugInfo debug information. |
| inst->UpdateDebugInfoFrom(varInst); |
| |
| replacements->push_back(inst); |
| } |
| |
| uint32_t ScalarReplacementPass::GetOrCreatePointerType(uint32_t id) { |
| auto iter = pointee_to_pointer_.find(id); |
| if (iter != pointee_to_pointer_.end()) return iter->second; |
| |
| analysis::Type* pointeeTy; |
| std::unique_ptr<analysis::Pointer> pointerTy; |
| std::tie(pointeeTy, pointerTy) = |
| context()->get_type_mgr()->GetTypeAndPointerType(id, |
| SpvStorageClassFunction); |
| uint32_t ptrId = 0; |
| if (pointeeTy->IsUniqueType()) { |
| // Non-ambiguous type, just ask the type manager for an id. |
| ptrId = context()->get_type_mgr()->GetTypeInstruction(pointerTy.get()); |
| pointee_to_pointer_[id] = ptrId; |
| return ptrId; |
| } |
| |
| // Ambiguous type. We must perform a linear search to try and find the right |
| // type. |
| for (auto global : context()->types_values()) { |
| if (global.opcode() == SpvOpTypePointer && |
| global.GetSingleWordInOperand(0u) == SpvStorageClassFunction && |
| global.GetSingleWordInOperand(1u) == id) { |
| if (get_decoration_mgr()->GetDecorationsFor(id, false).empty()) { |
| // Only reuse a decoration-less pointer of the correct type. |
| ptrId = global.result_id(); |
| break; |
| } |
| } |
| } |
| |
| if (ptrId != 0) { |
| pointee_to_pointer_[id] = ptrId; |
| return ptrId; |
| } |
| |
| ptrId = TakeNextId(); |
| context()->AddType(MakeUnique<Instruction>( |
| context(), SpvOpTypePointer, 0, ptrId, |
| std::initializer_list<Operand>{ |
| {SPV_OPERAND_TYPE_STORAGE_CLASS, {SpvStorageClassFunction}}, |
| {SPV_OPERAND_TYPE_ID, {id}}})); |
| Instruction* ptr = &*--context()->types_values_end(); |
| get_def_use_mgr()->AnalyzeInstDefUse(ptr); |
| pointee_to_pointer_[id] = ptrId; |
| // Register with the type manager if necessary. |
| context()->get_type_mgr()->RegisterType(ptrId, *pointerTy); |
| |
| return ptrId; |
| } |
| |
| void ScalarReplacementPass::GetOrCreateInitialValue(Instruction* source, |
| uint32_t index, |
| Instruction* newVar) { |
| assert(source->opcode() == SpvOpVariable); |
| if (source->NumInOperands() < 2) return; |
| |
| uint32_t initId = source->GetSingleWordInOperand(1u); |
| uint32_t storageId = GetStorageType(newVar)->result_id(); |
| Instruction* init = get_def_use_mgr()->GetDef(initId); |
| uint32_t newInitId = 0; |
| // TODO(dnovillo): Refactor this with constant propagation. |
| if (init->opcode() == SpvOpConstantNull) { |
| // Initialize to appropriate NULL. |
| auto iter = type_to_null_.find(storageId); |
| if (iter == type_to_null_.end()) { |
| newInitId = TakeNextId(); |
| type_to_null_[storageId] = newInitId; |
| context()->AddGlobalValue( |
| MakeUnique<Instruction>(context(), SpvOpConstantNull, storageId, |
| newInitId, std::initializer_list<Operand>{})); |
| Instruction* newNull = &*--context()->types_values_end(); |
| get_def_use_mgr()->AnalyzeInstDefUse(newNull); |
| } else { |
| newInitId = iter->second; |
| } |
| } else if (IsSpecConstantInst(init->opcode())) { |
| // Create a new constant extract. |
| newInitId = TakeNextId(); |
| context()->AddGlobalValue(MakeUnique<Instruction>( |
| context(), SpvOpSpecConstantOp, storageId, newInitId, |
| std::initializer_list<Operand>{ |
| {SPV_OPERAND_TYPE_SPEC_CONSTANT_OP_NUMBER, {SpvOpCompositeExtract}}, |
| {SPV_OPERAND_TYPE_ID, {init->result_id()}}, |
| {SPV_OPERAND_TYPE_LITERAL_INTEGER, {index}}})); |
| Instruction* newSpecConst = &*--context()->types_values_end(); |
| get_def_use_mgr()->AnalyzeInstDefUse(newSpecConst); |
| } else if (init->opcode() == SpvOpConstantComposite) { |
| // Get the appropriate index constant. |
| newInitId = init->GetSingleWordInOperand(index); |
| Instruction* element = get_def_use_mgr()->GetDef(newInitId); |
| if (element->opcode() == SpvOpUndef) { |
| // Undef is not a valid initializer for a variable. |
| newInitId = 0; |
| } |
| } else { |
| assert(false); |
| } |
| |
| if (newInitId != 0) { |
| newVar->AddOperand({SPV_OPERAND_TYPE_ID, {newInitId}}); |
| } |
| } |
| |
| uint64_t ScalarReplacementPass::GetArrayLength( |
| const Instruction* arrayType) const { |
| assert(arrayType->opcode() == SpvOpTypeArray); |
| const Instruction* length = |
| get_def_use_mgr()->GetDef(arrayType->GetSingleWordInOperand(1u)); |
| return context() |
| ->get_constant_mgr() |
| ->GetConstantFromInst(length) |
| ->GetZeroExtendedValue(); |
| } |
| |
| uint64_t ScalarReplacementPass::GetNumElements(const Instruction* type) const { |
| assert(type->opcode() == SpvOpTypeVector || |
| type->opcode() == SpvOpTypeMatrix); |
| const Operand& op = type->GetInOperand(1u); |
| assert(op.words.size() <= 2); |
| uint64_t len = 0; |
| for (size_t i = 0; i != op.words.size(); ++i) { |
| len |= (static_cast<uint64_t>(op.words[i]) << (32ull * i)); |
| } |
| return len; |
| } |
| |
| bool ScalarReplacementPass::IsSpecConstant(uint32_t id) const { |
| const Instruction* inst = get_def_use_mgr()->GetDef(id); |
| assert(inst); |
| return spvOpcodeIsSpecConstant(inst->opcode()); |
| } |
| |
| Instruction* ScalarReplacementPass::GetStorageType( |
| const Instruction* inst) const { |
| assert(inst->opcode() == SpvOpVariable); |
| |
| uint32_t ptrTypeId = inst->type_id(); |
| uint32_t typeId = |
| get_def_use_mgr()->GetDef(ptrTypeId)->GetSingleWordInOperand(1u); |
| return get_def_use_mgr()->GetDef(typeId); |
| } |
| |
| bool ScalarReplacementPass::CanReplaceVariable( |
| const Instruction* varInst) const { |
| assert(varInst->opcode() == SpvOpVariable); |
| |
| // Can only replace function scope variables. |
| if (varInst->GetSingleWordInOperand(0u) != SpvStorageClassFunction) { |
| return false; |
| } |
| |
| if (!CheckTypeAnnotations(get_def_use_mgr()->GetDef(varInst->type_id()))) { |
| return false; |
| } |
| |
| const Instruction* typeInst = GetStorageType(varInst); |
| if (!CheckType(typeInst)) { |
| return false; |
| } |
| |
| if (!CheckAnnotations(varInst)) { |
| return false; |
| } |
| |
| if (!CheckUses(varInst)) { |
| return false; |
| } |
| |
| return true; |
| } |
| |
| bool ScalarReplacementPass::CheckType(const Instruction* typeInst) const { |
| if (!CheckTypeAnnotations(typeInst)) { |
| return false; |
| } |
| |
| switch (typeInst->opcode()) { |
| case SpvOpTypeStruct: |
| // Don't bother with empty structs or very large structs. |
| if (typeInst->NumInOperands() == 0 || |
| IsLargerThanSizeLimit(typeInst->NumInOperands())) { |
| return false; |
| } |
| return true; |
| case SpvOpTypeArray: |
| if (IsSpecConstant(typeInst->GetSingleWordInOperand(1u))) { |
| return false; |
| } |
| if (IsLargerThanSizeLimit(GetArrayLength(typeInst))) { |
| return false; |
| } |
| return true; |
| // TODO(alanbaker): Develop some heuristics for when this should be |
| // re-enabled. |
| //// Specifically including matrix and vector in an attempt to reduce the |
| //// number of vector registers required. |
| // case SpvOpTypeMatrix: |
| // case SpvOpTypeVector: |
| // if (IsLargerThanSizeLimit(GetNumElements(typeInst))) return false; |
| // return true; |
| |
| case SpvOpTypeRuntimeArray: |
| default: |
| return false; |
| } |
| } |
| |
| bool ScalarReplacementPass::CheckTypeAnnotations( |
| const Instruction* typeInst) const { |
| for (auto inst : |
| get_decoration_mgr()->GetDecorationsFor(typeInst->result_id(), false)) { |
| uint32_t decoration; |
| if (inst->opcode() == SpvOpDecorate) { |
| decoration = inst->GetSingleWordInOperand(1u); |
| } else { |
| assert(inst->opcode() == SpvOpMemberDecorate); |
| decoration = inst->GetSingleWordInOperand(2u); |
| } |
| |
| switch (decoration) { |
| case SpvDecorationRowMajor: |
| case SpvDecorationColMajor: |
| case SpvDecorationArrayStride: |
| case SpvDecorationMatrixStride: |
| case SpvDecorationCPacked: |
| case SpvDecorationInvariant: |
| case SpvDecorationRestrict: |
| case SpvDecorationOffset: |
| case SpvDecorationAlignment: |
| case SpvDecorationAlignmentId: |
| case SpvDecorationMaxByteOffset: |
| case SpvDecorationRelaxedPrecision: |
| break; |
| default: |
| return false; |
| } |
| } |
| |
| return true; |
| } |
| |
| bool ScalarReplacementPass::CheckAnnotations(const Instruction* varInst) const { |
| for (auto inst : |
| get_decoration_mgr()->GetDecorationsFor(varInst->result_id(), false)) { |
| assert(inst->opcode() == SpvOpDecorate); |
| uint32_t decoration = inst->GetSingleWordInOperand(1u); |
| switch (decoration) { |
| case SpvDecorationInvariant: |
| case SpvDecorationRestrict: |
| case SpvDecorationAlignment: |
| case SpvDecorationAlignmentId: |
| case SpvDecorationMaxByteOffset: |
| break; |
| default: |
| return false; |
| } |
| } |
| |
| return true; |
| } |
| |
| bool ScalarReplacementPass::CheckUses(const Instruction* inst) const { |
| VariableStats stats = {0, 0}; |
| bool ok = CheckUses(inst, &stats); |
| |
| // TODO(alanbaker/greg-lunarg): Add some meaningful heuristics about when |
| // SRoA is costly, such as when the structure has many (unaccessed?) |
| // members. |
| |
| return ok; |
| } |
| |
| bool ScalarReplacementPass::CheckUses(const Instruction* inst, |
| VariableStats* stats) const { |
| uint64_t max_legal_index = GetMaxLegalIndex(inst); |
| |
| bool ok = true; |
| get_def_use_mgr()->ForEachUse(inst, [this, max_legal_index, stats, &ok]( |
| const Instruction* user, |
| uint32_t index) { |
| if (user->GetCommonDebugOpcode() == CommonDebugInfoDebugDeclare || |
| user->GetCommonDebugOpcode() == CommonDebugInfoDebugValue) { |
| // TODO: include num_partial_accesses if it uses Fragment operation or |
| // DebugValue has Indexes operand. |
| stats->num_full_accesses++; |
| return; |
| } |
| |
| // Annotations are check as a group separately. |
| if (!IsAnnotationInst(user->opcode())) { |
| switch (user->opcode()) { |
| case SpvOpAccessChain: |
| case SpvOpInBoundsAccessChain: |
| if (index == 2u && user->NumInOperands() > 1) { |
| uint32_t id = user->GetSingleWordInOperand(1u); |
| const Instruction* opInst = get_def_use_mgr()->GetDef(id); |
| const auto* constant = |
| context()->get_constant_mgr()->GetConstantFromInst(opInst); |
| if (!constant) { |
| ok = false; |
| } else if (constant->GetZeroExtendedValue() >= max_legal_index) { |
| ok = false; |
| } else { |
| if (!CheckUsesRelaxed(user)) ok = false; |
| } |
| stats->num_partial_accesses++; |
| } else { |
| ok = false; |
| } |
| break; |
| case SpvOpLoad: |
| if (!CheckLoad(user, index)) ok = false; |
| stats->num_full_accesses++; |
| break; |
| case SpvOpStore: |
| if (!CheckStore(user, index)) ok = false; |
| stats->num_full_accesses++; |
| break; |
| case SpvOpName: |
| case SpvOpMemberName: |
| break; |
| default: |
| ok = false; |
| break; |
| } |
| } |
| }); |
| |
| return ok; |
| } |
| |
| bool ScalarReplacementPass::CheckUsesRelaxed(const Instruction* inst) const { |
| bool ok = true; |
| get_def_use_mgr()->ForEachUse( |
| inst, [this, &ok](const Instruction* user, uint32_t index) { |
| switch (user->opcode()) { |
| case SpvOpAccessChain: |
| case SpvOpInBoundsAccessChain: |
| if (index != 2u) { |
| ok = false; |
| } else { |
| if (!CheckUsesRelaxed(user)) ok = false; |
| } |
| break; |
| case SpvOpLoad: |
| if (!CheckLoad(user, index)) ok = false; |
| break; |
| case SpvOpStore: |
| if (!CheckStore(user, index)) ok = false; |
| break; |
| case SpvOpImageTexelPointer: |
| if (!CheckImageTexelPointer(index)) ok = false; |
| break; |
| case SpvOpExtInst: |
| if (user->GetCommonDebugOpcode() != CommonDebugInfoDebugDeclare || |
| !CheckDebugDeclare(index)) |
| ok = false; |
| break; |
| default: |
| ok = false; |
| break; |
| } |
| }); |
| |
| return ok; |
| } |
| |
| bool ScalarReplacementPass::CheckImageTexelPointer(uint32_t index) const { |
| return index == 2u; |
| } |
| |
| bool ScalarReplacementPass::CheckLoad(const Instruction* inst, |
| uint32_t index) const { |
| if (index != 2u) return false; |
| if (inst->NumInOperands() >= 2 && |
| inst->GetSingleWordInOperand(1u) & SpvMemoryAccessVolatileMask) |
| return false; |
| return true; |
| } |
| |
| bool ScalarReplacementPass::CheckStore(const Instruction* inst, |
| uint32_t index) const { |
| if (index != 0u) return false; |
| if (inst->NumInOperands() >= 3 && |
| inst->GetSingleWordInOperand(2u) & SpvMemoryAccessVolatileMask) |
| return false; |
| return true; |
| } |
| |
| bool ScalarReplacementPass::CheckDebugDeclare(uint32_t index) const { |
| if (index != kDebugDeclareOperandVariableIndex) return false; |
| return true; |
| } |
| |
| bool ScalarReplacementPass::IsLargerThanSizeLimit(uint64_t length) const { |
| if (max_num_elements_ == 0) { |
| return false; |
| } |
| return length > max_num_elements_; |
| } |
| |
| std::unique_ptr<std::unordered_set<int64_t>> |
| ScalarReplacementPass::GetUsedComponents(Instruction* inst) { |
| std::unique_ptr<std::unordered_set<int64_t>> result( |
| new std::unordered_set<int64_t>()); |
| |
| analysis::DefUseManager* def_use_mgr = context()->get_def_use_mgr(); |
| |
| def_use_mgr->WhileEachUser(inst, [&result, def_use_mgr, |
| this](Instruction* use) { |
| switch (use->opcode()) { |
| case SpvOpLoad: { |
| // Look for extract from the load. |
| std::vector<uint32_t> t; |
| if (def_use_mgr->WhileEachUser(use, [&t](Instruction* use2) { |
| if (use2->opcode() != SpvOpCompositeExtract || |
| use2->NumInOperands() <= 1) { |
| return false; |
| } |
| t.push_back(use2->GetSingleWordInOperand(1)); |
| return true; |
| })) { |
| result->insert(t.begin(), t.end()); |
| return true; |
| } else { |
| result.reset(nullptr); |
| return false; |
| } |
| } |
| case SpvOpName: |
| case SpvOpMemberName: |
| case SpvOpStore: |
| // No components are used. |
| return true; |
| case SpvOpAccessChain: |
| case SpvOpInBoundsAccessChain: { |
| // Add the first index it if is a constant. |
| // TODO: Could be improved by checking if the address is used in a load. |
| analysis::ConstantManager* const_mgr = context()->get_constant_mgr(); |
| uint32_t index_id = use->GetSingleWordInOperand(1); |
| const analysis::Constant* index_const = |
| const_mgr->FindDeclaredConstant(index_id); |
| if (index_const) { |
| result->insert(index_const->GetSignExtendedValue()); |
| return true; |
| } else { |
| // Could be any element. Assuming all are used. |
| result.reset(nullptr); |
| return false; |
| } |
| } |
| default: |
| // We do not know what is happening. Have to assume the worst. |
| result.reset(nullptr); |
| return false; |
| } |
| }); |
| |
| return result; |
| } |
| |
| Instruction* ScalarReplacementPass::CreateNullConstant(uint32_t type_id) { |
| analysis::TypeManager* type_mgr = context()->get_type_mgr(); |
| analysis::ConstantManager* const_mgr = context()->get_constant_mgr(); |
| |
| const analysis::Type* type = type_mgr->GetType(type_id); |
| const analysis::Constant* null_const = const_mgr->GetConstant(type, {}); |
| Instruction* null_inst = |
| const_mgr->GetDefiningInstruction(null_const, type_id); |
| if (null_inst != nullptr) { |
| context()->UpdateDefUse(null_inst); |
| } |
| return null_inst; |
| } |
| |
| uint64_t ScalarReplacementPass::GetMaxLegalIndex( |
| const Instruction* var_inst) const { |
| assert(var_inst->opcode() == SpvOpVariable && |
| "|var_inst| must be a variable instruction."); |
| Instruction* type = GetStorageType(var_inst); |
| switch (type->opcode()) { |
| case SpvOpTypeStruct: |
| return type->NumInOperands(); |
| case SpvOpTypeArray: |
| return GetArrayLength(type); |
| case SpvOpTypeMatrix: |
| case SpvOpTypeVector: |
| return GetNumElements(type); |
| default: |
| return 0; |
| } |
| return 0; |
| } |
| |
| } // namespace opt |
| } // namespace spvtools |