LLVM 17.0.0git
CallGraphSCCPass.h
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1//===- CallGraphSCCPass.h - Pass that operates BU on call graph -*- C++ -*-===//
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file defines the CallGraphSCCPass class, which is used for passes which
10// are implemented as bottom-up traversals on the call graph. Because there may
11// be cycles in the call graph, passes of this type operate on the call-graph in
12// SCC order: that is, they process function bottom-up, except for recursive
13// functions, which they process all at once.
14//
15// These passes are inherently interprocedural, and are required to keep the
16// call graph up-to-date if they do anything which could modify it.
17//
18//===----------------------------------------------------------------------===//
19
20#ifndef LLVM_ANALYSIS_CALLGRAPHSCCPASS_H
21#define LLVM_ANALYSIS_CALLGRAPHSCCPASS_H
22
23#include "llvm/ADT/ArrayRef.h"
24#include "llvm/Pass.h"
25#include <vector>
26
27namespace llvm {
28
29class CallGraph;
30class CallGraphNode;
31class CallGraphSCC;
32class PMStack;
33
34class CallGraphSCCPass : public Pass {
35public:
36 explicit CallGraphSCCPass(char &pid) : Pass(PT_CallGraphSCC, pid) {}
37
38 /// createPrinterPass - Get a pass that prints the Module
39 /// corresponding to a CallGraph.
41 const std::string &Banner) const override;
42
45
46 /// doInitialization - This method is called before the SCC's of the program
47 /// has been processed, allowing the pass to do initialization as necessary.
48 virtual bool doInitialization(CallGraph &CG) {
49 return false;
50 }
51
52 /// runOnSCC - This method should be implemented by the subclass to perform
53 /// whatever action is necessary for the specified SCC. Note that
54 /// non-recursive (or only self-recursive) functions will have an SCC size of
55 /// 1, where recursive portions of the call graph will have SCC size > 1.
56 ///
57 /// SCC passes that add or delete functions to the SCC are required to update
58 /// the SCC list, otherwise stale pointers may be dereferenced.
59 virtual bool runOnSCC(CallGraphSCC &SCC) = 0;
60
61 /// doFinalization - This method is called after the SCC's of the program has
62 /// been processed, allowing the pass to do final cleanup as necessary.
63 virtual bool doFinalization(CallGraph &CG) {
64 return false;
65 }
66
67 /// Assign pass manager to manager this pass
68 void assignPassManager(PMStack &PMS, PassManagerType PMT) override;
69
70 /// Return what kind of Pass Manager can manage this pass.
73 }
74
75 /// getAnalysisUsage - For this class, we declare that we require and preserve
76 /// the call graph. If the derived class implements this method, it should
77 /// always explicitly call the implementation here.
78 void getAnalysisUsage(AnalysisUsage &Info) const override;
79
80protected:
81 /// Optional passes call this function to check whether the pass should be
82 /// skipped. This is the case when optimization bisect is over the limit.
83 bool skipSCC(CallGraphSCC &SCC) const;
84};
85
86/// CallGraphSCC - This is a single SCC that a CallGraphSCCPass is run on.
88 const CallGraph &CG; // The call graph for this SCC.
89 void *Context; // The CGPassManager object that is vending this.
90 std::vector<CallGraphNode *> Nodes;
91
92public:
93 CallGraphSCC(CallGraph &cg, void *context) : CG(cg), Context(context) {}
94
96 Nodes.assign(NewNodes.begin(), NewNodes.end());
97 }
98
99 bool isSingular() const { return Nodes.size() == 1; }
100 unsigned size() const { return Nodes.size(); }
101
102 /// ReplaceNode - This informs the SCC and the pass manager that the specified
103 /// Old node has been deleted, and New is to be used in its place.
104 void ReplaceNode(CallGraphNode *Old, CallGraphNode *New);
105
106 /// DeleteNode - This informs the SCC and the pass manager that the specified
107 /// Old node has been deleted.
108 void DeleteNode(CallGraphNode *Old);
109
110 using iterator = std::vector<CallGraphNode *>::const_iterator;
111
112 iterator begin() const { return Nodes.begin(); }
113 iterator end() const { return Nodes.end(); }
114
115 const CallGraph &getCallGraph() { return CG; }
116};
117
119
120/// This pass is required by interprocedural register allocation. It forces
121/// codegen to follow bottom up order on call graph.
123public:
124 static char ID;
125
129 }
130
131 bool runOnSCC(CallGraphSCC &SCC) override { return false; }
132
133 void getAnalysisUsage(AnalysisUsage &AU) const override {
134 AU.setPreservesAll();
135 }
136};
137
138} // end namespace llvm
139
140#endif // LLVM_ANALYSIS_CALLGRAPHSCCPASS_H
Analysis containing CSE Info
Definition: CSEInfo.cpp:27
LLVMContext & Context
Represent the analysis usage information of a pass.
void setPreservesAll()
Set by analyses that do not transform their input at all.
ArrayRef - Represent a constant reference to an array (0 or more elements consecutively in memory),...
Definition: ArrayRef.h:41
iterator end() const
Definition: ArrayRef.h:152
iterator begin() const
Definition: ArrayRef.h:151
A node in the call graph for a module.
Definition: CallGraph.h:166
virtual bool doFinalization(CallGraph &CG)
doFinalization - This method is called after the SCC's of the program has been processed,...
PassManagerType getPotentialPassManagerType() const override
Return what kind of Pass Manager can manage this pass.
Pass * createPrinterPass(raw_ostream &OS, const std::string &Banner) const override
createPrinterPass - Get a pass that prints the Module corresponding to a CallGraph.
virtual bool runOnSCC(CallGraphSCC &SCC)=0
runOnSCC - This method should be implemented by the subclass to perform whatever action is necessary ...
void getAnalysisUsage(AnalysisUsage &Info) const override
getAnalysisUsage - For this class, we declare that we require and preserve the call graph.
bool skipSCC(CallGraphSCC &SCC) const
Optional passes call this function to check whether the pass should be skipped.
virtual bool doInitialization(CallGraph &CG)
doInitialization - This method is called before the SCC's of the program has been processed,...
void assignPassManager(PMStack &PMS, PassManagerType PMT) override
Assign pass manager to manager this pass.
CallGraphSCC - This is a single SCC that a CallGraphSCCPass is run on.
bool isSingular() const
std::vector< CallGraphNode * >::const_iterator iterator
const CallGraph & getCallGraph()
void ReplaceNode(CallGraphNode *Old, CallGraphNode *New)
ReplaceNode - This informs the SCC and the pass manager that the specified Old node has been deleted,...
void DeleteNode(CallGraphNode *Old)
DeleteNode - This informs the SCC and the pass manager that the specified Old node has been deleted.
void initialize(ArrayRef< CallGraphNode * > NewNodes)
unsigned size() const
iterator begin() const
iterator end() const
CallGraphSCC(CallGraph &cg, void *context)
The basic data container for the call graph of a Module of IR.
Definition: CallGraph.h:72
This pass is required by interprocedural register allocation.
bool runOnSCC(CallGraphSCC &SCC) override
runOnSCC - This method should be implemented by the subclass to perform whatever action is necessary ...
void getAnalysisUsage(AnalysisUsage &AU) const override
getAnalysisUsage - For this class, we declare that we require and preserve the call graph.
PMStack - This class implements a stack data structure of PMDataManager pointers.
PassRegistry - This class manages the registration and intitialization of the pass subsystem as appli...
Definition: PassRegistry.h:38
static PassRegistry * getPassRegistry()
getPassRegistry - Access the global registry object, which is automatically initialized at applicatio...
Pass interface - Implemented by all 'passes'.
Definition: Pass.h:91
virtual bool doInitialization(Module &)
doInitialization - Virtual method overridden by subclasses to do any necessary initialization before ...
Definition: Pass.h:116
virtual bool doFinalization(Module &)
doFinalization - Virtual method overriden by subclasses to do any necessary clean up after all passes...
Definition: Pass.h:120
A global registry used in conjunction with static constructors to make pluggable components (like tar...
Definition: Registry.h:44
This class implements an extremely fast bulk output stream that can only output to a stream.
Definition: raw_ostream.h:52
This is an optimization pass for GlobalISel generic memory operations.
Definition: AddressRanges.h:18
@ PT_CallGraphSCC
Definition: Pass.h:67
PassManagerType
Different types of internal pass managers.
Definition: Pass.h:52
@ PMT_CallGraphPassManager
CGPassManager.
Definition: Pass.h:55
void initializeDummyCGSCCPassPass(PassRegistry &)