mirror of
https://github.com/KhronosGroup/SPIRV-Tools
synced 2024-10-19 11:30:15 +00:00
760789f58d
Don't stop just after one because of short-circuiting logical-or.
345 lines
11 KiB
C++
345 lines
11 KiB
C++
// Copyright (c) 2017 The Khronos Group Inc.
|
|
// Copyright (c) 2017 Valve Corporation
|
|
// Copyright (c) 2017 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 "iterator.h"
|
|
#include "local_single_block_elim_pass.h"
|
|
|
|
static const int kSpvEntryPointFunctionId = 1;
|
|
static const int kSpvStorePtrId = 0;
|
|
static const int kSpvStoreValId = 1;
|
|
static const int kSpvLoadPtrId = 0;
|
|
static const int kSpvAccessChainPtrId = 0;
|
|
static const int kSpvTypePointerStorageClass = 0;
|
|
static const int kSpvTypePointerTypeId = 1;
|
|
|
|
namespace spvtools {
|
|
namespace opt {
|
|
|
|
bool LocalSingleBlockLoadStoreElimPass::IsNonPtrAccessChain(
|
|
const SpvOp opcode) const {
|
|
return opcode == SpvOpAccessChain || opcode == SpvOpInBoundsAccessChain;
|
|
}
|
|
|
|
bool LocalSingleBlockLoadStoreElimPass::IsMathType(
|
|
const ir::Instruction* typeInst) const {
|
|
switch (typeInst->opcode()) {
|
|
case SpvOpTypeInt:
|
|
case SpvOpTypeFloat:
|
|
case SpvOpTypeBool:
|
|
case SpvOpTypeVector:
|
|
case SpvOpTypeMatrix:
|
|
return true;
|
|
default:
|
|
break;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
bool LocalSingleBlockLoadStoreElimPass::IsTargetType(
|
|
const ir::Instruction* typeInst) const {
|
|
if (IsMathType(typeInst))
|
|
return true;
|
|
if (typeInst->opcode() == SpvOpTypeArray)
|
|
return IsMathType(def_use_mgr_->GetDef(typeInst->GetSingleWordOperand(1)));
|
|
if (typeInst->opcode() != SpvOpTypeStruct)
|
|
return false;
|
|
// All struct members must be math type
|
|
int nonMathComp = 0;
|
|
typeInst->ForEachInId([&nonMathComp,this](const uint32_t* tid) {
|
|
ir::Instruction* compTypeInst = def_use_mgr_->GetDef(*tid);
|
|
if (!IsMathType(compTypeInst)) ++nonMathComp;
|
|
});
|
|
return nonMathComp == 0;
|
|
}
|
|
|
|
ir::Instruction* LocalSingleBlockLoadStoreElimPass::GetPtr(
|
|
ir::Instruction* ip, uint32_t* varId) {
|
|
*varId = ip->GetSingleWordInOperand(
|
|
ip->opcode() == SpvOpStore ? kSpvStorePtrId : kSpvLoadPtrId);
|
|
ir::Instruction* ptrInst = def_use_mgr_->GetDef(*varId);
|
|
ir::Instruction* varInst = ptrInst;
|
|
while (IsNonPtrAccessChain(varInst->opcode())) {
|
|
*varId = varInst->GetSingleWordInOperand(kSpvAccessChainPtrId);
|
|
varInst = def_use_mgr_->GetDef(*varId);
|
|
}
|
|
return ptrInst;
|
|
}
|
|
|
|
bool LocalSingleBlockLoadStoreElimPass::IsTargetVar(uint32_t varId) {
|
|
if (seen_non_target_vars_.find(varId) != seen_non_target_vars_.end())
|
|
return false;
|
|
if (seen_target_vars_.find(varId) != seen_target_vars_.end())
|
|
return true;
|
|
const ir::Instruction* varInst = def_use_mgr_->GetDef(varId);
|
|
assert(varInst->opcode() == SpvOpVariable);
|
|
const uint32_t varTypeId = varInst->type_id();
|
|
const ir::Instruction* varTypeInst = def_use_mgr_->GetDef(varTypeId);
|
|
if (varTypeInst->GetSingleWordInOperand(kSpvTypePointerStorageClass) !=
|
|
SpvStorageClassFunction) {
|
|
seen_non_target_vars_.insert(varId);
|
|
return false;
|
|
}
|
|
const uint32_t varPteTypeId =
|
|
varTypeInst->GetSingleWordInOperand(kSpvTypePointerTypeId);
|
|
ir::Instruction* varPteTypeInst = def_use_mgr_->GetDef(varPteTypeId);
|
|
if (!IsTargetType(varPteTypeInst)) {
|
|
seen_non_target_vars_.insert(varId);
|
|
return false;
|
|
}
|
|
seen_target_vars_.insert(varId);
|
|
return true;
|
|
}
|
|
|
|
void LocalSingleBlockLoadStoreElimPass::ReplaceAndDeleteLoad(
|
|
ir::Instruction* loadInst, uint32_t replId) {
|
|
const uint32_t loadId = loadInst->result_id();
|
|
(void) def_use_mgr_->ReplaceAllUsesWith(loadId, replId);
|
|
// TODO(greg-lunarg): Consider moving DCE into separate pass
|
|
DCEInst(loadInst);
|
|
}
|
|
|
|
bool LocalSingleBlockLoadStoreElimPass::HasLoads(uint32_t ptrId) const {
|
|
analysis::UseList* uses = def_use_mgr_->GetUses(ptrId);
|
|
if (uses == nullptr)
|
|
return false;
|
|
for (auto u : *uses) {
|
|
SpvOp op = u.inst->opcode();
|
|
if (IsNonPtrAccessChain(op)) {
|
|
if (HasLoads(u.inst->result_id()))
|
|
return true;
|
|
}
|
|
else {
|
|
// Conservatively assume that calls will do a load
|
|
// TODO(): Improve analysis around function calls
|
|
if (op == SpvOpLoad || op == SpvOpFunctionCall)
|
|
return true;
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
|
|
bool LocalSingleBlockLoadStoreElimPass::IsLiveVar(uint32_t varId) const {
|
|
// non-function scope vars are live
|
|
const ir::Instruction* varInst = def_use_mgr_->GetDef(varId);
|
|
assert(varInst->opcode() == SpvOpVariable);
|
|
const uint32_t varTypeId = varInst->type_id();
|
|
const ir::Instruction* varTypeInst = def_use_mgr_->GetDef(varTypeId);
|
|
if (varTypeInst->GetSingleWordInOperand(kSpvTypePointerStorageClass) !=
|
|
SpvStorageClassFunction)
|
|
return true;
|
|
// test if variable is loaded from
|
|
return HasLoads(varId);
|
|
}
|
|
|
|
bool LocalSingleBlockLoadStoreElimPass::IsLiveStore(
|
|
ir::Instruction* storeInst) {
|
|
// get store's variable
|
|
uint32_t varId;
|
|
(void) GetPtr(storeInst, &varId);
|
|
return IsLiveVar(varId);
|
|
}
|
|
|
|
void LocalSingleBlockLoadStoreElimPass::AddStores(
|
|
uint32_t ptr_id, std::queue<ir::Instruction*>* insts) {
|
|
analysis::UseList* uses = def_use_mgr_->GetUses(ptr_id);
|
|
if (uses != nullptr) {
|
|
for (auto u : *uses) {
|
|
if (IsNonPtrAccessChain(u.inst->opcode()))
|
|
AddStores(u.inst->result_id(), insts);
|
|
else if (u.inst->opcode() == SpvOpStore)
|
|
insts->push(u.inst);
|
|
}
|
|
}
|
|
}
|
|
|
|
void LocalSingleBlockLoadStoreElimPass::DCEInst(ir::Instruction* inst) {
|
|
std::queue<ir::Instruction*> deadInsts;
|
|
deadInsts.push(inst);
|
|
while (!deadInsts.empty()) {
|
|
ir::Instruction* di = deadInsts.front();
|
|
// Don't delete labels
|
|
if (di->opcode() == SpvOpLabel) {
|
|
deadInsts.pop();
|
|
continue;
|
|
}
|
|
// Remember operands
|
|
std::vector<uint32_t> ids;
|
|
di->ForEachInId([&ids](uint32_t* iid) {
|
|
ids.push_back(*iid);
|
|
});
|
|
uint32_t varId = 0;
|
|
// Remember variable if dead load
|
|
if (di->opcode() == SpvOpLoad)
|
|
(void) GetPtr(di, &varId);
|
|
def_use_mgr_->KillInst(di);
|
|
// For all operands with no remaining uses, add their instruction
|
|
// to the dead instruction queue.
|
|
for (auto id : ids) {
|
|
analysis::UseList* uses = def_use_mgr_->GetUses(id);
|
|
if (uses == nullptr)
|
|
deadInsts.push(def_use_mgr_->GetDef(id));
|
|
}
|
|
// if a load was deleted and it was the variable's
|
|
// last load, add all its stores to dead queue
|
|
if (varId != 0 && !IsLiveVar(varId))
|
|
AddStores(varId, &deadInsts);
|
|
deadInsts.pop();
|
|
}
|
|
}
|
|
|
|
bool LocalSingleBlockLoadStoreElimPass::LocalSingleBlockLoadStoreElim(
|
|
ir::Function* func) {
|
|
// Verify no CopyObject ops in function. This is a pre-SSA pass and
|
|
// is generally not useful for code already in CSSA form.
|
|
for (auto& blk : *func)
|
|
for (auto& inst : blk)
|
|
if (inst.opcode() == SpvOpCopyObject)
|
|
return false;
|
|
// Perform local store/load and load/load elimination on each block
|
|
bool modified = false;
|
|
for (auto bi = func->begin(); bi != func->end(); ++bi) {
|
|
var2store_.clear();
|
|
var2load_.clear();
|
|
pinned_vars_.clear();
|
|
for (auto ii = bi->begin(); ii != bi->end(); ++ii) {
|
|
switch (ii->opcode()) {
|
|
case SpvOpStore: {
|
|
// Verify store variable is target type
|
|
uint32_t varId;
|
|
ir::Instruction* ptrInst = GetPtr(&*ii, &varId);
|
|
if (!IsTargetVar(varId))
|
|
continue;
|
|
// Register the store
|
|
if (ptrInst->opcode() == SpvOpVariable) {
|
|
// if not pinned, look for WAW
|
|
if (pinned_vars_.find(varId) == pinned_vars_.end()) {
|
|
auto si = var2store_.find(varId);
|
|
if (si != var2store_.end()) {
|
|
def_use_mgr_->KillInst(si->second);
|
|
}
|
|
}
|
|
var2store_[varId] = &*ii;
|
|
}
|
|
else {
|
|
assert(IsNonPtrAccessChain(ptrInst->opcode()));
|
|
var2store_.erase(varId);
|
|
}
|
|
pinned_vars_.erase(varId);
|
|
var2load_.erase(varId);
|
|
} break;
|
|
case SpvOpLoad: {
|
|
// Verify store variable is target type
|
|
uint32_t varId;
|
|
ir::Instruction* ptrInst = GetPtr(&*ii, &varId);
|
|
if (!IsTargetVar(varId))
|
|
continue;
|
|
// Look for previous store or load
|
|
uint32_t replId = 0;
|
|
if (ptrInst->opcode() == SpvOpVariable) {
|
|
auto si = var2store_.find(varId);
|
|
if (si != var2store_.end()) {
|
|
replId = si->second->GetSingleWordInOperand(kSpvStoreValId);
|
|
}
|
|
else {
|
|
auto li = var2load_.find(varId);
|
|
if (li != var2load_.end()) {
|
|
replId = li->second->result_id();
|
|
}
|
|
}
|
|
}
|
|
if (replId != 0) {
|
|
// replace load's result id and delete load
|
|
ReplaceAndDeleteLoad(&*ii, replId);
|
|
modified = true;
|
|
}
|
|
else {
|
|
if (ptrInst->opcode() == SpvOpVariable)
|
|
var2load_[varId] = &*ii; // register load
|
|
pinned_vars_.insert(varId);
|
|
}
|
|
} break;
|
|
case SpvOpFunctionCall: {
|
|
// Conservatively assume all locals are redefined for now.
|
|
// TODO(): Handle more optimally
|
|
var2store_.clear();
|
|
var2load_.clear();
|
|
pinned_vars_.clear();
|
|
} break;
|
|
default:
|
|
break;
|
|
}
|
|
}
|
|
// Go back and delete useless stores in block
|
|
// TODO(greg-lunarg): Consider moving DCE into separate pass
|
|
for (auto ii = bi->begin(); ii != bi->end(); ++ii) {
|
|
if (ii->opcode() != SpvOpStore)
|
|
continue;
|
|
if (IsLiveStore(&*ii))
|
|
continue;
|
|
DCEInst(&*ii);
|
|
}
|
|
}
|
|
return modified;
|
|
}
|
|
|
|
void LocalSingleBlockLoadStoreElimPass::Initialize(ir::Module* module) {
|
|
|
|
module_ = module;
|
|
|
|
// Initialize function and block maps
|
|
id2function_.clear();
|
|
for (auto& fn : *module_)
|
|
id2function_[fn.result_id()] = &fn;
|
|
|
|
// Initialize Target Type Caches
|
|
seen_target_vars_.clear();
|
|
seen_non_target_vars_.clear();
|
|
|
|
// TODO(): Reuse def/use from previous passes
|
|
def_use_mgr_.reset(new analysis::DefUseManager(consumer(), module_));
|
|
|
|
// Start new ids with next availablein module
|
|
next_id_ = module_->id_bound();
|
|
|
|
};
|
|
|
|
Pass::Status LocalSingleBlockLoadStoreElimPass::ProcessImpl() {
|
|
// Assumes logical addressing only
|
|
if (module_->HasCapability(SpvCapabilityAddresses))
|
|
return Status::SuccessWithoutChange;
|
|
bool modified = false;
|
|
// Call Mem2Reg on all remaining functions.
|
|
for (auto& e : module_->entry_points()) {
|
|
ir::Function* fn =
|
|
id2function_[e.GetSingleWordOperand(kSpvEntryPointFunctionId)];
|
|
modified = LocalSingleBlockLoadStoreElim(fn) || modified;
|
|
}
|
|
FinalizeNextId(module_);
|
|
return modified ? Status::SuccessWithChange : Status::SuccessWithoutChange;
|
|
}
|
|
|
|
LocalSingleBlockLoadStoreElimPass::LocalSingleBlockLoadStoreElimPass()
|
|
: module_(nullptr), def_use_mgr_(nullptr), next_id_(0) {}
|
|
|
|
Pass::Status LocalSingleBlockLoadStoreElimPass::Process(ir::Module* module) {
|
|
Initialize(module);
|
|
return ProcessImpl();
|
|
}
|
|
|
|
} // namespace opt
|
|
} // namespace spvtools
|
|
|