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| //===-- 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
|