InlinerPass.h revision c5e1ec47c719806fcc882470595960512edc7441 
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 INLINER_H
18#define INLINER_H
19
20#include "llvm/CallGraphSCCPass.h"
21#include "llvm/Transforms/Utils/InlineCost.h"
22
23namespace llvm {
24  class CallSite;
25
26/// Inliner - This class contains all of the helper code which is used to
27/// perform the inlining operations that do not depend on the policy.
28///
29struct Inliner : public CallGraphSCCPass {
30  explicit Inliner(void *ID);
31  explicit Inliner(void *ID, int Threshold);
32
33  /// getAnalysisUsage - For this class, we declare that we require and preserve
34  /// the call graph.  If the derived class implements this method, it should
35  /// always explicitly call the implementation here.
36  virtual void getAnalysisUsage(AnalysisUsage &Info) const;
37
38  // Main run interface method, this implements the interface required by the
39  // Pass class.
40  virtual bool runOnSCC(const std::vector<CallGraphNode *> &SCC);
41
42  // doFinalization - Remove now-dead linkonce functions at the end of
43  // processing to avoid breaking the SCC traversal.
44  virtual bool doFinalization(CallGraph &CG);
45
46
47  /// This method returns the value specified by the -inline-threshold value,
48  /// specified on the command line.  This is typically not directly needed.
49  ///
50  unsigned getInlineThreshold() const { return InlineThreshold; }
51
52  /// getInlineCost - This method must be implemented by the subclass to
53  /// determine the cost of inlining the specified call site.  If the cost
54  /// returned is greater than the current inline threshold, the call site is
55  /// not inlined.
56  ///
57  virtual InlineCost getInlineCost(CallSite CS) = 0;
58
59  // getInlineFudgeFactor - Return a > 1.0 factor if the inliner should use a
60  // higher threshold to determine if the function call should be inlined.
61  ///
62  virtual float getInlineFudgeFactor(CallSite CS) = 0;
63
64private:
65  // InlineThreshold - Cache the value here for easy access.
66  unsigned InlineThreshold;
67
68  /// shouldInline - Return true if the inliner should attempt to
69  /// inline at the given CallSite.
70  bool shouldInline(CallSite CS);
71};
72
73} // End llvm namespace
74
75#endif
76