1//===- CallGraphUpdater.h - A (lazy) call graph update helper ---*- 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/// \file
9///
10/// This file provides interfaces used to manipulate a call graph, regardless
11/// if it is a "old style" CallGraph or an "new style" LazyCallGraph.
12///
13//===----------------------------------------------------------------------===//
14
15#ifndef LLVM_TRANSFORMS_UTILS_CALLGRAPHUPDATER_H
16#define LLVM_TRANSFORMS_UTILS_CALLGRAPHUPDATER_H
17
18#include "llvm/Analysis/CGSCCPassManager.h"
19#include "llvm/Analysis/LazyCallGraph.h"
20
21namespace llvm {
22
23class CallGraph;
24class CallGraphSCC;
25
26/// Wrapper to unify "old style" CallGraph and "new style" LazyCallGraph. This
27/// simplifies the interface and the call sites, e.g., new and old pass manager
28/// passes can share the same code.
29class CallGraphUpdater {
30 /// Containers for functions which we did replace or want to delete when
31 /// `finalize` is called. This can happen explicitly or as part of the
32 /// destructor. Dead functions in comdat sections are tracked separately
33 /// because a function with discardable linakage in a COMDAT should only
34 /// be dropped if the entire COMDAT is dropped, see git ac07703842cf.
35 ///{
36 SmallPtrSet<Function *, 16> ReplacedFunctions;
37 SmallVector<Function *, 16> DeadFunctions;
38 SmallVector<Function *, 16> DeadFunctionsInComdats;
39 ///}
40
41 /// Old PM variables
42 ///{
43 CallGraph *CG = nullptr;
44 CallGraphSCC *CGSCC = nullptr;
45 ///}
46
47 /// New PM variables
48 ///{
49 LazyCallGraph *LCG = nullptr;
50 LazyCallGraph::SCC *SCC = nullptr;
51 CGSCCAnalysisManager *AM = nullptr;
52 CGSCCUpdateResult *UR = nullptr;
53 FunctionAnalysisManager *FAM = nullptr;
54 ///}
55
56public:
57 CallGraphUpdater() = default;
58 ~CallGraphUpdater() { finalize(); }
59
60 /// Initializers for usage outside of a CGSCC pass, inside a CGSCC pass in
61 /// the old and new pass manager (PM).
62 ///{
63 void initialize(CallGraph &CG, CallGraphSCC &SCC) {
64 this->CG = &CG;
65 this->CGSCC = &SCC;
66 }
67 void initialize(LazyCallGraph &LCG, LazyCallGraph::SCC &SCC,
68 CGSCCAnalysisManager &AM, CGSCCUpdateResult &UR) {
69 this->LCG = &LCG;
70 this->SCC = &SCC;
71 this->AM = &AM;
72 this->UR = &UR;
73 FAM =
74 &AM.getResult<FunctionAnalysisManagerCGSCCProxy>(IR&: SCC, ExtraArgs&: LCG).getManager();
75 }
76 ///}
77
78 /// Finalizer that will trigger actions like function removal from the CG.
79 bool finalize();
80
81 /// Remove \p Fn from the call graph.
82 void removeFunction(Function &Fn);
83
84 /// After an CGSCC pass changes a function in ways that affect the call
85 /// graph, this method can be called to update it.
86 void reanalyzeFunction(Function &Fn);
87
88 /// If a new function was created by outlining, this method can be called
89 /// to update the call graph for the new function. Note that the old one
90 /// still needs to be re-analyzed or manually updated.
91 void registerOutlinedFunction(Function &OriginalFn, Function &NewFn);
92
93 /// Replace \p OldFn in the call graph (and SCC) with \p NewFn. The uses
94 /// outside the call graph and the function \p OldFn are not modified.
95 /// Note that \p OldFn is also removed from the call graph
96 /// (\see removeFunction).
97 void replaceFunctionWith(Function &OldFn, Function &NewFn);
98
99 /// Remove the call site \p CS from the call graph.
100 void removeCallSite(CallBase &CS);
101
102 /// Replace \p OldCS with the new call site \p NewCS.
103 /// \return True if the replacement was successful, otherwise False. In the
104 /// latter case the parent function of \p OldCB needs to be re-analyzed.
105 bool replaceCallSite(CallBase &OldCS, CallBase &NewCS);
106};
107
108} // end namespace llvm
109
110#endif // LLVM_TRANSFORMS_UTILS_CALLGRAPHUPDATER_H
111

source code of llvm/include/llvm/Transforms/Utils/CallGraphUpdater.h