1 //===- InlinerPass.h - Code common to all inliners --------------*- C++ -*-===// 2 // 3 // The LLVM Compiler Infrastructure 4 // 5 // This file is distributed under the University of Illinois Open Source 6 // License. See LICENSE.TXT for details. 7 // 8 //===----------------------------------------------------------------------===// 9 // 10 // This file defines a simple policy-based bottom-up inliner. This file 11 // implements all of the boring mechanics of the bottom-up inlining, while the 12 // subclass determines WHAT to inline, which is the much more interesting 13 // component. 14 // 15 //===----------------------------------------------------------------------===// 16 17 #ifndef LLVM_TRANSFORMS_IPO_INLINERPASS_H 18 #define LLVM_TRANSFORMS_IPO_INLINERPASS_H 19 20 #include "llvm/CallGraphSCCPass.h" 21 22 namespace llvm { 23 class CallSite; 24 class TargetData; 25 class InlineCost; 26 template<class PtrType, unsigned SmallSize> 27 class SmallPtrSet; 28 29 /// Inliner - This class contains all of the helper code which is used to 30 /// perform the inlining operations that do not depend on the policy. 31 /// 32 struct Inliner : public CallGraphSCCPass { 33 explicit Inliner(char &ID); 34 explicit Inliner(char &ID, int Threshold, bool InsertLifetime); 35 36 /// getAnalysisUsage - For this class, we declare that we require and preserve 37 /// the call graph. If the derived class implements this method, it should 38 /// always explicitly call the implementation here. 39 virtual void getAnalysisUsage(AnalysisUsage &Info) const; 40 41 // Main run interface method, this implements the interface required by the 42 // Pass class. 43 virtual bool runOnSCC(CallGraphSCC &SCC); 44 45 // doFinalization - Remove now-dead linkonce functions at the end of 46 // processing to avoid breaking the SCC traversal. 47 virtual bool doFinalization(CallGraph &CG); 48 49 /// This method returns the value specified by the -inline-threshold value, 50 /// specified on the command line. This is typically not directly needed. 51 /// getInlineThresholdInliner52 unsigned getInlineThreshold() const { return InlineThreshold; } 53 54 /// Calculate the inline threshold for given Caller. This threshold is lower 55 /// if the caller is marked with OptimizeForSize and -inline-threshold is not 56 /// given on the comand line. It is higher if the callee is marked with the 57 /// inlinehint attribute. 58 /// 59 unsigned getInlineThreshold(CallSite CS) const; 60 61 /// getInlineCost - This method must be implemented by the subclass to 62 /// determine the cost of inlining the specified call site. If the cost 63 /// returned is greater than the current inline threshold, the call site is 64 /// not inlined. 65 /// 66 virtual InlineCost getInlineCost(CallSite CS) = 0; 67 68 /// removeDeadFunctions - Remove dead functions. 69 /// 70 /// This also includes a hack in the form of the 'AlwaysInlineOnly' flag 71 /// which restricts it to deleting functions with an 'AlwaysInline' 72 /// attribute. This is useful for the InlineAlways pass that only wants to 73 /// deal with that subset of the functions. 74 bool removeDeadFunctions(CallGraph &CG, bool AlwaysInlineOnly = false); 75 76 private: 77 // InlineThreshold - Cache the value here for easy access. 78 unsigned InlineThreshold; 79 80 // InsertLifetime - Insert @llvm.lifetime intrinsics. 81 bool InsertLifetime; 82 83 /// shouldInline - Return true if the inliner should attempt to 84 /// inline at the given CallSite. 85 bool shouldInline(CallSite CS); 86 }; 87 88 } // End llvm namespace 89 90 #endif 91