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