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//===-- UnifyFunctionExitNodes.h - Ensure fn's have one return --*- C++ -*-===//
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// The LLVM Compiler Infrastructure
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//===----------------------------------------------------------------------===//
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// This pass is used to ensure that functions have at most one return and one
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// unwind instruction in them. Additionally, it keeps track of which node is
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// the new exit node of the CFG. If there are no return or unwind instructions
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// in the function, the getReturnBlock/getUnwindBlock methods will return a null
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//===----------------------------------------------------------------------===//
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#ifndef LLVM_TRANSFORMS_UNIFYFUNCTIONEXITNODES_H
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#define LLVM_TRANSFORMS_UNIFYFUNCTIONEXITNODES_H
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#include "llvm/Pass.h"
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struct UnifyFunctionExitNodes : public FunctionPass {
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BasicBlock *ReturnBlock, *UnwindBlock, *UnreachableBlock;
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static char ID; // Pass identification, replacement for typeid
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UnifyFunctionExitNodes() : FunctionPass(ID),
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ReturnBlock(0), UnwindBlock(0) {}
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// We can preserve non-critical-edgeness when we unify function exit nodes
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virtual void getAnalysisUsage(AnalysisUsage &AU) const;
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// getReturn|Unwind|UnreachableBlock - Return the new single (or nonexistant)
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// return, unwind, or unreachable basic blocks in the CFG.
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BasicBlock *getReturnBlock() const { return ReturnBlock; }
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BasicBlock *getUnwindBlock() const { return UnwindBlock; }
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BasicBlock *getUnreachableBlock() const { return UnreachableBlock; }
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virtual bool runOnFunction(Function &F);
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Pass *createUnifyFunctionExitNodesPass();
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} // End llvm namespace