57 lines
1.8 KiB
C++
57 lines
1.8 KiB
C++
// 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/eliminate_dead_functions_pass.h"
|
|
|
|
#include <unordered_set>
|
|
|
|
#include "source/opt/ir_context.h"
|
|
|
|
namespace spvtools {
|
|
namespace opt {
|
|
|
|
Pass::Status EliminateDeadFunctionsPass::Process() {
|
|
// Identify live functions first. Those that are not live
|
|
// are dead.
|
|
std::unordered_set<const Function*> live_function_set;
|
|
ProcessFunction mark_live = [&live_function_set](Function* fp) {
|
|
live_function_set.insert(fp);
|
|
return false;
|
|
};
|
|
context()->ProcessReachableCallTree(mark_live);
|
|
|
|
bool modified = false;
|
|
for (auto funcIter = get_module()->begin();
|
|
funcIter != get_module()->end();) {
|
|
if (live_function_set.count(&*funcIter) == 0) {
|
|
modified = true;
|
|
EliminateFunction(&*funcIter);
|
|
funcIter = funcIter.Erase();
|
|
} else {
|
|
++funcIter;
|
|
}
|
|
}
|
|
|
|
return modified ? Pass::Status::SuccessWithChange
|
|
: Pass::Status::SuccessWithoutChange;
|
|
}
|
|
|
|
void EliminateDeadFunctionsPass::EliminateFunction(Function* func) {
|
|
// Remove all of the instruction in the function body
|
|
func->ForEachInst([this](Instruction* inst) { context()->KillInst(inst); },
|
|
true);
|
|
}
|
|
} // namespace opt
|
|
} // namespace spvtools
|