mirror of
https://github.com/KhronosGroup/SPIRV-Tools
synced 2024-11-24 12:30:13 +00:00
d6c067630d
It is legal, but not generated by any SPIR-V producer: an OpCompositeExtract with no indexes. This is essentially just a copy of the object, so we treat them that way. We simply propagate the live variables of the result to the operand. Fixes https://crbug.com/919181.
398 lines
14 KiB
C++
398 lines
14 KiB
C++
// Copyright (c) 2018 Google LLC.
|
|
//
|
|
// 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/vector_dce.h"
|
|
|
|
#include <utility>
|
|
|
|
namespace spvtools {
|
|
namespace opt {
|
|
namespace {
|
|
|
|
const uint32_t kExtractCompositeIdInIdx = 0;
|
|
const uint32_t kInsertObjectIdInIdx = 0;
|
|
const uint32_t kInsertCompositeIdInIdx = 1;
|
|
|
|
} // namespace
|
|
|
|
Pass::Status VectorDCE::Process() {
|
|
bool modified = false;
|
|
for (Function& function : *get_module()) {
|
|
modified |= VectorDCEFunction(&function);
|
|
}
|
|
return (modified ? Status::SuccessWithChange : Status::SuccessWithoutChange);
|
|
}
|
|
|
|
bool VectorDCE::VectorDCEFunction(Function* function) {
|
|
LiveComponentMap live_components;
|
|
FindLiveComponents(function, &live_components);
|
|
return RewriteInstructions(function, live_components);
|
|
}
|
|
|
|
void VectorDCE::FindLiveComponents(Function* function,
|
|
LiveComponentMap* live_components) {
|
|
std::vector<WorkListItem> work_list;
|
|
|
|
// Prime the work list. We will assume that any instruction that does
|
|
// not result in a vector is live.
|
|
//
|
|
// Extending to structures and matrices is not as straight forward because of
|
|
// the nesting. We cannot simply us a bit vector to keep track of which
|
|
// components are live because of arbitrary nesting of structs.
|
|
function->ForEachInst(
|
|
[&work_list, this, live_components](Instruction* current_inst) {
|
|
if (!HasVectorOrScalarResult(current_inst) ||
|
|
!context()->IsCombinatorInstruction(current_inst)) {
|
|
MarkUsesAsLive(current_inst, all_components_live_, live_components,
|
|
&work_list);
|
|
}
|
|
});
|
|
|
|
// Process the work list propagating liveness.
|
|
for (uint32_t i = 0; i < work_list.size(); i++) {
|
|
WorkListItem current_item = work_list[i];
|
|
Instruction* current_inst = current_item.instruction;
|
|
|
|
switch (current_inst->opcode()) {
|
|
case SpvOpCompositeExtract:
|
|
MarkExtractUseAsLive(current_inst, current_item.components,
|
|
live_components, &work_list);
|
|
break;
|
|
case SpvOpCompositeInsert:
|
|
MarkInsertUsesAsLive(current_item, live_components, &work_list);
|
|
break;
|
|
case SpvOpVectorShuffle:
|
|
MarkVectorShuffleUsesAsLive(current_item, live_components, &work_list);
|
|
break;
|
|
case SpvOpCompositeConstruct:
|
|
MarkCompositeContructUsesAsLive(current_item, live_components,
|
|
&work_list);
|
|
break;
|
|
default:
|
|
if (current_inst->IsScalarizable()) {
|
|
MarkUsesAsLive(current_inst, current_item.components, live_components,
|
|
&work_list);
|
|
} else {
|
|
MarkUsesAsLive(current_inst, all_components_live_, live_components,
|
|
&work_list);
|
|
}
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
void VectorDCE::MarkExtractUseAsLive(const Instruction* current_inst,
|
|
const utils::BitVector& live_elements,
|
|
LiveComponentMap* live_components,
|
|
std::vector<WorkListItem>* work_list) {
|
|
analysis::DefUseManager* def_use_mgr = context()->get_def_use_mgr();
|
|
uint32_t operand_id =
|
|
current_inst->GetSingleWordInOperand(kExtractCompositeIdInIdx);
|
|
Instruction* operand_inst = def_use_mgr->GetDef(operand_id);
|
|
|
|
if (HasVectorOrScalarResult(operand_inst)) {
|
|
WorkListItem new_item;
|
|
new_item.instruction = operand_inst;
|
|
if (current_inst->NumInOperands() < 2) {
|
|
new_item.components = live_elements;
|
|
} else {
|
|
new_item.components.Set(current_inst->GetSingleWordInOperand(1));
|
|
}
|
|
AddItemToWorkListIfNeeded(new_item, live_components, work_list);
|
|
}
|
|
}
|
|
|
|
void VectorDCE::MarkInsertUsesAsLive(
|
|
const VectorDCE::WorkListItem& current_item,
|
|
LiveComponentMap* live_components,
|
|
std::vector<VectorDCE::WorkListItem>* work_list) {
|
|
analysis::DefUseManager* def_use_mgr = context()->get_def_use_mgr();
|
|
|
|
if (current_item.instruction->NumInOperands() > 2) {
|
|
uint32_t insert_position =
|
|
current_item.instruction->GetSingleWordInOperand(2);
|
|
|
|
// Add the elements of the composite object that are used.
|
|
uint32_t operand_id = current_item.instruction->GetSingleWordInOperand(
|
|
kInsertCompositeIdInIdx);
|
|
Instruction* operand_inst = def_use_mgr->GetDef(operand_id);
|
|
|
|
WorkListItem new_item;
|
|
new_item.instruction = operand_inst;
|
|
new_item.components = current_item.components;
|
|
new_item.components.Clear(insert_position);
|
|
|
|
AddItemToWorkListIfNeeded(new_item, live_components, work_list);
|
|
|
|
// Add the element being inserted if it is used.
|
|
if (current_item.components.Get(insert_position)) {
|
|
uint32_t obj_operand_id =
|
|
current_item.instruction->GetSingleWordInOperand(
|
|
kInsertObjectIdInIdx);
|
|
Instruction* obj_operand_inst = def_use_mgr->GetDef(obj_operand_id);
|
|
WorkListItem new_item_for_obj;
|
|
new_item_for_obj.instruction = obj_operand_inst;
|
|
new_item_for_obj.components.Set(0);
|
|
AddItemToWorkListIfNeeded(new_item_for_obj, live_components, work_list);
|
|
}
|
|
} else {
|
|
// If there are no indices, then this is a copy of the object being
|
|
// inserted.
|
|
uint32_t object_id =
|
|
current_item.instruction->GetSingleWordInOperand(kInsertObjectIdInIdx);
|
|
Instruction* object_inst = def_use_mgr->GetDef(object_id);
|
|
|
|
WorkListItem new_item;
|
|
new_item.instruction = object_inst;
|
|
new_item.components = current_item.components;
|
|
AddItemToWorkListIfNeeded(new_item, live_components, work_list);
|
|
}
|
|
}
|
|
|
|
void VectorDCE::MarkVectorShuffleUsesAsLive(
|
|
const WorkListItem& current_item,
|
|
VectorDCE::LiveComponentMap* live_components,
|
|
std::vector<WorkListItem>* work_list) {
|
|
analysis::DefUseManager* def_use_mgr = context()->get_def_use_mgr();
|
|
|
|
WorkListItem first_operand;
|
|
first_operand.instruction =
|
|
def_use_mgr->GetDef(current_item.instruction->GetSingleWordInOperand(0));
|
|
WorkListItem second_operand;
|
|
second_operand.instruction =
|
|
def_use_mgr->GetDef(current_item.instruction->GetSingleWordInOperand(1));
|
|
|
|
analysis::TypeManager* type_mgr = context()->get_type_mgr();
|
|
analysis::Vector* first_type =
|
|
type_mgr->GetType(first_operand.instruction->type_id())->AsVector();
|
|
uint32_t size_of_first_operand = first_type->element_count();
|
|
|
|
for (uint32_t in_op = 2; in_op < current_item.instruction->NumInOperands();
|
|
++in_op) {
|
|
uint32_t index = current_item.instruction->GetSingleWordInOperand(in_op);
|
|
if (current_item.components.Get(in_op - 2)) {
|
|
if (index < size_of_first_operand) {
|
|
first_operand.components.Set(index);
|
|
} else {
|
|
second_operand.components.Set(index - size_of_first_operand);
|
|
}
|
|
}
|
|
}
|
|
|
|
AddItemToWorkListIfNeeded(first_operand, live_components, work_list);
|
|
AddItemToWorkListIfNeeded(second_operand, live_components, work_list);
|
|
}
|
|
|
|
void VectorDCE::MarkCompositeContructUsesAsLive(
|
|
VectorDCE::WorkListItem work_item,
|
|
VectorDCE::LiveComponentMap* live_components,
|
|
std::vector<VectorDCE::WorkListItem>* work_list) {
|
|
analysis::DefUseManager* def_use_mgr = context()->get_def_use_mgr();
|
|
analysis::TypeManager* type_mgr = context()->get_type_mgr();
|
|
|
|
uint32_t current_component = 0;
|
|
Instruction* current_inst = work_item.instruction;
|
|
uint32_t num_in_operands = current_inst->NumInOperands();
|
|
for (uint32_t i = 0; i < num_in_operands; ++i) {
|
|
uint32_t id = current_inst->GetSingleWordInOperand(i);
|
|
Instruction* op_inst = def_use_mgr->GetDef(id);
|
|
|
|
if (HasScalarResult(op_inst)) {
|
|
WorkListItem new_work_item;
|
|
new_work_item.instruction = op_inst;
|
|
if (work_item.components.Get(current_component)) {
|
|
new_work_item.components.Set(0);
|
|
}
|
|
AddItemToWorkListIfNeeded(new_work_item, live_components, work_list);
|
|
current_component++;
|
|
} else {
|
|
assert(HasVectorResult(op_inst));
|
|
WorkListItem new_work_item;
|
|
new_work_item.instruction = op_inst;
|
|
uint32_t op_vector_size =
|
|
type_mgr->GetType(op_inst->type_id())->AsVector()->element_count();
|
|
|
|
for (uint32_t op_vector_idx = 0; op_vector_idx < op_vector_size;
|
|
op_vector_idx++, current_component++) {
|
|
if (work_item.components.Get(current_component)) {
|
|
new_work_item.components.Set(op_vector_idx);
|
|
}
|
|
}
|
|
AddItemToWorkListIfNeeded(new_work_item, live_components, work_list);
|
|
}
|
|
}
|
|
}
|
|
|
|
void VectorDCE::MarkUsesAsLive(
|
|
Instruction* current_inst, const utils::BitVector& live_elements,
|
|
LiveComponentMap* live_components,
|
|
std::vector<VectorDCE::WorkListItem>* work_list) {
|
|
analysis::DefUseManager* def_use_mgr = context()->get_def_use_mgr();
|
|
|
|
current_inst->ForEachInId([&work_list, &live_elements, this, live_components,
|
|
def_use_mgr](uint32_t* operand_id) {
|
|
Instruction* operand_inst = def_use_mgr->GetDef(*operand_id);
|
|
|
|
if (HasVectorResult(operand_inst)) {
|
|
WorkListItem new_item;
|
|
new_item.instruction = operand_inst;
|
|
new_item.components = live_elements;
|
|
AddItemToWorkListIfNeeded(new_item, live_components, work_list);
|
|
} else if (HasScalarResult(operand_inst)) {
|
|
WorkListItem new_item;
|
|
new_item.instruction = operand_inst;
|
|
new_item.components.Set(0);
|
|
AddItemToWorkListIfNeeded(new_item, live_components, work_list);
|
|
}
|
|
});
|
|
}
|
|
|
|
bool VectorDCE::HasVectorOrScalarResult(const Instruction* inst) const {
|
|
return HasScalarResult(inst) || HasVectorResult(inst);
|
|
}
|
|
|
|
bool VectorDCE::HasVectorResult(const Instruction* inst) const {
|
|
analysis::TypeManager* type_mgr = context()->get_type_mgr();
|
|
if (inst->type_id() == 0) {
|
|
return false;
|
|
}
|
|
|
|
const analysis::Type* current_type = type_mgr->GetType(inst->type_id());
|
|
switch (current_type->kind()) {
|
|
case analysis::Type::kVector:
|
|
return true;
|
|
default:
|
|
return false;
|
|
}
|
|
}
|
|
|
|
bool VectorDCE::HasScalarResult(const Instruction* inst) const {
|
|
analysis::TypeManager* type_mgr = context()->get_type_mgr();
|
|
if (inst->type_id() == 0) {
|
|
return false;
|
|
}
|
|
|
|
const analysis::Type* current_type = type_mgr->GetType(inst->type_id());
|
|
switch (current_type->kind()) {
|
|
case analysis::Type::kBool:
|
|
case analysis::Type::kInteger:
|
|
case analysis::Type::kFloat:
|
|
return true;
|
|
default:
|
|
return false;
|
|
}
|
|
}
|
|
|
|
bool VectorDCE::RewriteInstructions(
|
|
Function* function, const VectorDCE::LiveComponentMap& live_components) {
|
|
bool modified = false;
|
|
function->ForEachInst(
|
|
[&modified, this, live_components](Instruction* current_inst) {
|
|
if (!context()->IsCombinatorInstruction(current_inst)) {
|
|
return;
|
|
}
|
|
|
|
auto live_component = live_components.find(current_inst->result_id());
|
|
if (live_component == live_components.end()) {
|
|
// If this instruction is not in live_components then it does not
|
|
// produce a vector, or it is never referenced and ADCE will remove
|
|
// it. No point in trying to differentiate.
|
|
return;
|
|
}
|
|
|
|
// If no element in the current instruction is used replace it with an
|
|
// OpUndef.
|
|
if (live_component->second.Empty()) {
|
|
modified = true;
|
|
uint32_t undef_id = this->Type2Undef(current_inst->type_id());
|
|
context()->KillNamesAndDecorates(current_inst);
|
|
context()->ReplaceAllUsesWith(current_inst->result_id(), undef_id);
|
|
context()->KillInst(current_inst);
|
|
return;
|
|
}
|
|
|
|
switch (current_inst->opcode()) {
|
|
case SpvOpCompositeInsert:
|
|
modified |=
|
|
RewriteInsertInstruction(current_inst, live_component->second);
|
|
break;
|
|
case SpvOpCompositeConstruct:
|
|
// TODO: The members that are not live can be replaced by an undef
|
|
// or constant. This will remove uses of those values, and possibly
|
|
// create opportunities for ADCE.
|
|
break;
|
|
default:
|
|
// Do nothing.
|
|
break;
|
|
}
|
|
});
|
|
return modified;
|
|
}
|
|
|
|
bool VectorDCE::RewriteInsertInstruction(
|
|
Instruction* current_inst, const utils::BitVector& live_components) {
|
|
// If the value being inserted is not live, then we can skip the insert.
|
|
|
|
if (current_inst->NumInOperands() == 2) {
|
|
// If there are no indices, then this is the same as a copy.
|
|
context()->KillNamesAndDecorates(current_inst->result_id());
|
|
uint32_t object_id =
|
|
current_inst->GetSingleWordInOperand(kInsertObjectIdInIdx);
|
|
context()->ReplaceAllUsesWith(current_inst->result_id(), object_id);
|
|
return true;
|
|
}
|
|
|
|
uint32_t insert_index = current_inst->GetSingleWordInOperand(2);
|
|
if (!live_components.Get(insert_index)) {
|
|
context()->KillNamesAndDecorates(current_inst->result_id());
|
|
uint32_t composite_id =
|
|
current_inst->GetSingleWordInOperand(kInsertCompositeIdInIdx);
|
|
context()->ReplaceAllUsesWith(current_inst->result_id(), composite_id);
|
|
return true;
|
|
}
|
|
|
|
// If the values already in the composite are not used, then replace it with
|
|
// an undef.
|
|
utils::BitVector temp = live_components;
|
|
temp.Clear(insert_index);
|
|
if (temp.Empty()) {
|
|
context()->ForgetUses(current_inst);
|
|
uint32_t undef_id = Type2Undef(current_inst->type_id());
|
|
current_inst->SetInOperand(kInsertCompositeIdInIdx, {undef_id});
|
|
context()->AnalyzeUses(current_inst);
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
void VectorDCE::AddItemToWorkListIfNeeded(
|
|
WorkListItem work_item, VectorDCE::LiveComponentMap* live_components,
|
|
std::vector<WorkListItem>* work_list) {
|
|
Instruction* current_inst = work_item.instruction;
|
|
auto it = live_components->find(current_inst->result_id());
|
|
if (it == live_components->end()) {
|
|
live_components->emplace(
|
|
std::make_pair(current_inst->result_id(), work_item.components));
|
|
work_list->emplace_back(work_item);
|
|
} else {
|
|
if (it->second.Or(work_item.components)) {
|
|
work_list->emplace_back(work_item);
|
|
}
|
|
}
|
|
}
|
|
|
|
} // namespace opt
|
|
} // namespace spvtools
|