diff options
Diffstat (limited to 'source/opt/eliminate_dead_input_components_pass.cpp')
| -rw-r--r-- | source/opt/eliminate_dead_input_components_pass.cpp | 189 |
1 files changed, 189 insertions, 0 deletions
diff --git a/source/opt/eliminate_dead_input_components_pass.cpp b/source/opt/eliminate_dead_input_components_pass.cpp new file mode 100644 index 00000000..aa2776bb --- /dev/null +++ b/source/opt/eliminate_dead_input_components_pass.cpp @@ -0,0 +1,189 @@ +// Copyright (c) 2022 The Khronos Group Inc. +// Copyright (c) 2022 LunarG 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/eliminate_dead_input_components_pass.h" + +#include <set> +#include <vector> + +#include "source/opt/instruction.h" +#include "source/opt/ir_builder.h" +#include "source/opt/ir_context.h" +#include "source/util/bit_vector.h" + +namespace { + +const uint32_t kAccessChainBaseInIdx = 0; +const uint32_t kAccessChainIndex0InIdx = 1; +const uint32_t kConstantValueInIdx = 0; +const uint32_t kVariableStorageClassInIdx = 0; + +} // namespace + +namespace spvtools { +namespace opt { + +Pass::Status EliminateDeadInputComponentsPass::Process() { + // Current functionality assumes shader capability + if (!context()->get_feature_mgr()->HasCapability(SpvCapabilityShader)) + return Status::SuccessWithoutChange; + analysis::DefUseManager* def_use_mgr = context()->get_def_use_mgr(); + analysis::TypeManager* type_mgr = context()->get_type_mgr(); + bool modified = false; + std::vector<std::pair<Instruction*, unsigned>> arrays_to_change; + for (auto& var : context()->types_values()) { + if (var.opcode() != SpvOpVariable) { + continue; + } + analysis::Type* var_type = type_mgr->GetType(var.type_id()); + analysis::Pointer* ptr_type = var_type->AsPointer(); + if (ptr_type == nullptr) { + continue; + } + if (ptr_type->storage_class() != SpvStorageClassInput) { + continue; + } + const analysis::Array* arr_type = ptr_type->pointee_type()->AsArray(); + if (arr_type != nullptr) { + unsigned arr_len_id = arr_type->LengthId(); + Instruction* arr_len_inst = def_use_mgr->GetDef(arr_len_id); + if (arr_len_inst->opcode() != SpvOpConstant) { + continue; + } + // SPIR-V requires array size is >= 1, so this works for signed or + // unsigned size + unsigned original_max = + arr_len_inst->GetSingleWordInOperand(kConstantValueInIdx) - 1; + unsigned max_idx = FindMaxIndex(var, original_max); + if (max_idx != original_max) { + ChangeArrayLength(var, max_idx + 1); + modified = true; + } + continue; + } + const analysis::Struct* struct_type = ptr_type->pointee_type()->AsStruct(); + if (struct_type == nullptr) continue; + const auto elt_types = struct_type->element_types(); + unsigned original_max = static_cast<unsigned>(elt_types.size()) - 1; + unsigned max_idx = FindMaxIndex(var, original_max); + if (max_idx != original_max) { + ChangeStructLength(var, max_idx + 1); + modified = true; + } + } + + return modified ? Status::SuccessWithChange : Status::SuccessWithoutChange; +} + +unsigned EliminateDeadInputComponentsPass::FindMaxIndex(Instruction& var, + unsigned original_max) { + unsigned max = 0; + bool seen_non_const_ac = false; + assert(var.opcode() == SpvOpVariable && "must be variable"); + context()->get_def_use_mgr()->WhileEachUser( + var.result_id(), [&max, &seen_non_const_ac, var, this](Instruction* use) { + auto use_opcode = use->opcode(); + if (use_opcode == SpvOpLoad || use_opcode == SpvOpCopyMemory || + use_opcode == SpvOpCopyMemorySized || + use_opcode == SpvOpCopyObject) { + seen_non_const_ac = true; + return false; + } + if (use->opcode() != SpvOpAccessChain && + use->opcode() != SpvOpInBoundsAccessChain) { + return true; + } + // OpAccessChain with no indices currently not optimized + if (use->NumInOperands() == 1) { + seen_non_const_ac = true; + return false; + } + unsigned base_id = use->GetSingleWordInOperand(kAccessChainBaseInIdx); + USE_ASSERT(base_id == var.result_id() && "unexpected base"); + unsigned idx_id = use->GetSingleWordInOperand(kAccessChainIndex0InIdx); + Instruction* idx_inst = context()->get_def_use_mgr()->GetDef(idx_id); + if (idx_inst->opcode() != SpvOpConstant) { + seen_non_const_ac = true; + return false; + } + unsigned value = idx_inst->GetSingleWordInOperand(kConstantValueInIdx); + if (value > max) max = value; + return true; + }); + return seen_non_const_ac ? original_max : max; +} + +void EliminateDeadInputComponentsPass::ChangeArrayLength(Instruction& arr_var, + unsigned length) { + analysis::TypeManager* type_mgr = context()->get_type_mgr(); + analysis::ConstantManager* const_mgr = context()->get_constant_mgr(); + analysis::DefUseManager* def_use_mgr = context()->get_def_use_mgr(); + analysis::Pointer* ptr_type = + type_mgr->GetType(arr_var.type_id())->AsPointer(); + const analysis::Array* arr_ty = ptr_type->pointee_type()->AsArray(); + assert(arr_ty && "expecting array type"); + uint32_t length_id = const_mgr->GetUIntConst(length); + analysis::Array new_arr_ty(arr_ty->element_type(), + arr_ty->GetConstantLengthInfo(length_id, length)); + analysis::Type* reg_new_arr_ty = type_mgr->GetRegisteredType(&new_arr_ty); + analysis::Pointer new_ptr_ty(reg_new_arr_ty, SpvStorageClassInput); + analysis::Type* reg_new_ptr_ty = type_mgr->GetRegisteredType(&new_ptr_ty); + uint32_t new_ptr_ty_id = type_mgr->GetTypeInstruction(reg_new_ptr_ty); + arr_var.SetResultType(new_ptr_ty_id); + def_use_mgr->AnalyzeInstUse(&arr_var); + // Move arr_var after its new type to preserve order + USE_ASSERT(arr_var.GetSingleWordInOperand(kVariableStorageClassInIdx) != + SpvStorageClassFunction && + "cannot move Function variable"); + Instruction* new_ptr_ty_inst = def_use_mgr->GetDef(new_ptr_ty_id); + arr_var.RemoveFromList(); + arr_var.InsertAfter(new_ptr_ty_inst); +} + +void EliminateDeadInputComponentsPass::ChangeStructLength( + Instruction& struct_var, unsigned length) { + analysis::TypeManager* type_mgr = context()->get_type_mgr(); + analysis::Pointer* ptr_type = + type_mgr->GetType(struct_var.type_id())->AsPointer(); + const analysis::Struct* struct_ty = ptr_type->pointee_type()->AsStruct(); + assert(struct_ty && "expecting struct type"); + const auto orig_elt_types = struct_ty->element_types(); + std::vector<const analysis::Type*> new_elt_types; + for (unsigned u = 0; u < length; ++u) + new_elt_types.push_back(orig_elt_types[u]); + analysis::Struct new_struct_ty(new_elt_types); + analysis::Type* reg_new_struct_ty = + type_mgr->GetRegisteredType(&new_struct_ty); + uint32_t new_struct_ty_id = type_mgr->GetTypeInstruction(reg_new_struct_ty); + uint32_t old_struct_ty_id = type_mgr->GetTypeInstruction(struct_ty); + analysis::DecorationManager* deco_mgr = context()->get_decoration_mgr(); + deco_mgr->CloneDecorations(old_struct_ty_id, new_struct_ty_id); + analysis::Pointer new_ptr_ty(reg_new_struct_ty, SpvStorageClassInput); + analysis::Type* reg_new_ptr_ty = type_mgr->GetRegisteredType(&new_ptr_ty); + uint32_t new_ptr_ty_id = type_mgr->GetTypeInstruction(reg_new_ptr_ty); + struct_var.SetResultType(new_ptr_ty_id); + analysis::DefUseManager* def_use_mgr = context()->get_def_use_mgr(); + def_use_mgr->AnalyzeInstUse(&struct_var); + // Move struct_var after its new type to preserve order + USE_ASSERT(struct_var.GetSingleWordInOperand(kVariableStorageClassInIdx) != + SpvStorageClassFunction && + "cannot move Function variable"); + Instruction* new_ptr_ty_inst = def_use_mgr->GetDef(new_ptr_ty_id); + struct_var.RemoveFromList(); + struct_var.InsertAfter(new_ptr_ty_inst); +} + +} // namespace opt +} // namespace spvtools |