37 lines
1.4 KiB
C++
37 lines
1.4 KiB
C++
//===-- UnreachableBlockElim.h - Remove unreachable blocks for codegen --===//
|
|
//
|
|
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
|
|
// See https://llvm.org/LICENSE.txt for license information.
|
|
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// This pass is an extremely simple version of the SimplifyCFG pass. Its sole
|
|
// job is to delete LLVM basic blocks that are not reachable from the entry
|
|
// node. To do this, it performs a simple depth first traversal of the CFG,
|
|
// then deletes any unvisited nodes.
|
|
//
|
|
// Note that this pass is really a hack. In particular, the instruction
|
|
// selectors for various targets should just not generate code for unreachable
|
|
// blocks. Until LLVM has a more systematic way of defining instruction
|
|
// selectors, however, we cannot really expect them to handle additional
|
|
// complexity.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#ifndef LLVM_LIB_CODEGEN_UNREACHABLEBLOCKELIM_H
|
|
#define LLVM_LIB_CODEGEN_UNREACHABLEBLOCKELIM_H
|
|
|
|
#include "llvm/IR/PassManager.h"
|
|
|
|
namespace llvm {
|
|
|
|
class UnreachableBlockElimPass
|
|
: public PassInfoMixin<UnreachableBlockElimPass> {
|
|
public:
|
|
PreservedAnalyses run(Function &F, FunctionAnalysisManager &AM);
|
|
};
|
|
} // end namespace llvm
|
|
|
|
#endif // LLVM_LIB_CODEGEN_UNREACHABLEBLOCKELIM_H
|