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//===- CallGraphSCCPass.h - Pass that operates BU on call graph -*- 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 file defines the CallGraphSCCPass class, which is used for passes which
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// are implemented as bottom-up traversals on the call graph. Because there may
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// be cycles in the call graph, passes of this type operate on the call-graph in
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// SCC order: that is, they process function bottom-up, except for recursive
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// functions, which they process all at once.
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// These passes are inherently interprocedural, and are required to keep the
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// call graph up-to-date if they do anything which could modify it.
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//===----------------------------------------------------------------------===//
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#ifndef LLVM_CALL_GRAPH_SCC_PASS_H
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#define LLVM_CALL_GRAPH_SCC_PASS_H
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#include "llvm/Pass.h"
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#include "llvm/Analysis/CallGraph.h"
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class CallGraphSCCPass : public Pass {
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explicit CallGraphSCCPass(char &pid) : Pass(PT_CallGraphSCC, pid) {}
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/// createPrinterPass - Get a pass that prints the Module
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/// corresponding to a CallGraph.
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Pass *createPrinterPass(raw_ostream &O, const std::string &Banner) const;
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/// doInitialization - This method is called before the SCC's of the program
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/// has been processed, allowing the pass to do initialization as necessary.
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virtual bool doInitialization(CallGraph &CG) {
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/// runOnSCC - This method should be implemented by the subclass to perform
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/// whatever action is necessary for the specified SCC. Note that
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/// non-recursive (or only self-recursive) functions will have an SCC size of
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/// 1, where recursive portions of the call graph will have SCC size > 1.
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/// SCC passes that add or delete functions to the SCC are required to update
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/// the SCC list, otherwise stale pointers may be dereferenced.
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virtual bool runOnSCC(CallGraphSCC &SCC) = 0;
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/// doFinalization - This method is called after the SCC's of the program has
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/// been processed, allowing the pass to do final cleanup as necessary.
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virtual bool doFinalization(CallGraph &CG) {
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/// Assign pass manager to manager this pass
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virtual void assignPassManager(PMStack &PMS,
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/// Return what kind of Pass Manager can manage this pass.
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virtual PassManagerType getPotentialPassManagerType() const {
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return PMT_CallGraphPassManager;
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/// getAnalysisUsage - For this class, we declare that we require and preserve
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/// the call graph. If the derived class implements this method, it should
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/// always explicitly call the implementation here.
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virtual void getAnalysisUsage(AnalysisUsage &Info) const;
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/// CallGraphSCC - This is a single SCC that a CallGraphSCCPass is run on.
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void *Context; // The CGPassManager object that is vending this.
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std::vector<CallGraphNode*> Nodes;
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CallGraphSCC(void *context) : Context(context) {}
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void initialize(CallGraphNode*const*I, CallGraphNode*const*E) {
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bool isSingular() const { return Nodes.size() == 1; }
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unsigned size() const { return Nodes.size(); }
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/// ReplaceNode - This informs the SCC and the pass manager that the specified
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/// Old node has been deleted, and New is to be used in its place.
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void ReplaceNode(CallGraphNode *Old, CallGraphNode *New);
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typedef std::vector<CallGraphNode*>::const_iterator iterator;
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iterator begin() const { return Nodes.begin(); }
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iterator end() const { return Nodes.end(); }
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} // End llvm namespace