1 //===- Inliner.h - Inliner pass and infrastructure --------------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 #ifndef LLVM_TRANSFORMS_IPO_INLINER_H
11 #define LLVM_TRANSFORMS_IPO_INLINER_H
13 #include "llvm/Analysis/CGSCCPassManager.h"
14 #include "llvm/Analysis/CallGraphSCCPass.h"
15 #include "llvm/Analysis/InlineCost.h"
16 #include "llvm/Analysis/LazyCallGraph.h"
17 #include "llvm/IR/CallSite.h"
18 #include "llvm/IR/PassManager.h"
19 #include "llvm/Transforms/Utils/ImportedFunctionsInliningStatistics.h"
24 class AssumptionCacheTracker;
26 class ProfileSummaryInfo;
28 /// This class contains all of the helper code which is used to perform the
29 /// inlining operations that do not depend on the policy. It contains the core
30 /// bottom-up inlining infrastructure that specific inliner passes use.
31 struct LegacyInlinerBase : public CallGraphSCCPass {
32 explicit LegacyInlinerBase(char &ID);
33 explicit LegacyInlinerBase(char &ID, bool InsertLifetime);
35 /// For this class, we declare that we require and preserve the call graph.
36 /// If the derived class implements this method, it should always explicitly
37 /// call the implementation here.
38 void getAnalysisUsage(AnalysisUsage &Info) const override;
40 bool doInitialization(CallGraph &CG) override;
42 /// Main run interface method, this implements the interface required by the
44 bool runOnSCC(CallGraphSCC &SCC) override;
46 using llvm::Pass::doFinalization;
48 /// Remove now-dead linkonce functions at the end of processing to avoid
49 /// breaking the SCC traversal.
50 bool doFinalization(CallGraph &CG) override;
52 /// This method must be implemented by the subclass to determine the cost of
53 /// inlining the specified call site. If the cost returned is greater than
54 /// the current inline threshold, the call site is not inlined.
55 virtual InlineCost getInlineCost(CallSite CS) = 0;
57 /// Remove dead functions.
59 /// This also includes a hack in the form of the 'AlwaysInlineOnly' flag
60 /// which restricts it to deleting functions with an 'AlwaysInline'
61 /// attribute. This is useful for the InlineAlways pass that only wants to
62 /// deal with that subset of the functions.
63 bool removeDeadFunctions(CallGraph &CG, bool AlwaysInlineOnly = false);
65 /// This function performs the main work of the pass. The default of
66 /// Inlinter::runOnSCC() calls skipSCC() before calling this method, but
67 /// derived classes which cannot be skipped can override that method and call
68 /// this function unconditionally.
69 bool inlineCalls(CallGraphSCC &SCC);
72 // Insert @llvm.lifetime intrinsics.
73 bool InsertLifetime = true;
76 AssumptionCacheTracker *ACT;
77 ProfileSummaryInfo *PSI;
78 ImportedFunctionsInliningStatistics ImportedFunctionsStats;
81 /// The inliner pass for the new pass manager.
83 /// This pass wires together the inlining utilities and the inline cost
84 /// analysis into a CGSCC pass. It considers every call in every function in
85 /// the SCC and tries to inline if profitable. It can be tuned with a number of
86 /// parameters to control what cost model is used and what tradeoffs are made
87 /// when making the decision.
89 /// It should be noted that the legacy inliners do considerably more than this
90 /// inliner pass does. They provide logic for manually merging allocas, and
91 /// doing considerable DCE including the DCE of dead functions. This pass makes
92 /// every attempt to be simpler. DCE of functions requires complex reasoning
93 /// about comdat groups, etc. Instead, it is expected that other more focused
94 /// passes be composed to achieve the same end result.
95 class InlinerPass : public PassInfoMixin<InlinerPass> {
97 InlinerPass(InlineParams Params = getInlineParams())
98 : Params(std::move(Params)) {}
100 InlinerPass(InlinerPass &&Arg)
101 : Params(std::move(Arg.Params)),
102 ImportedFunctionsStats(std::move(Arg.ImportedFunctionsStats)) {}
104 PreservedAnalyses run(LazyCallGraph::SCC &C, CGSCCAnalysisManager &AM,
105 LazyCallGraph &CG, CGSCCUpdateResult &UR);
109 std::unique_ptr<ImportedFunctionsInliningStatistics> ImportedFunctionsStats;
112 } // end namespace llvm
114 #endif // LLVM_TRANSFORMS_IPO_INLINER_H