LibCallAliasAnalysis.h revision 1f74590e9d1b9cf0f1f81a156efea73f76546e05 
1//===- LibCallAliasAnalysis.h - Implement AliasAnalysis for libcalls ------===//
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 the LibCallAliasAnalysis class.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_ANALYSIS_LIBCALL_AA_H
15#define LLVM_ANALYSIS_LIBCALL_AA_H
16
17#include "llvm/Analysis/AliasAnalysis.h"
18#include "llvm/Pass.h"
19
20namespace llvm {
21  class LibCallInfo;
22  struct LibCallFunctionInfo;
23
24  /// LibCallAliasAnalysis - Alias analysis driven from LibCallInfo.
25  struct LibCallAliasAnalysis : public FunctionPass, public AliasAnalysis {
26    static char ID; // Class identification
27
28    LibCallInfo *LCI;
29
30    explicit LibCallAliasAnalysis(LibCallInfo *LC = 0)
31      : FunctionPass(&ID), LCI(LC) {
32    }
33    explicit LibCallAliasAnalysis(const void *ID, LibCallInfo *LC)
34      : FunctionPass(ID), LCI(LC) {
35    }
36    ~LibCallAliasAnalysis();
37
38    ModRefResult getModRefInfo(ImmutableCallSite CS,
39                               const Value *P, unsigned Size);
40
41    ModRefResult getModRefInfo(ImmutableCallSite CS1,
42                               ImmutableCallSite CS2) {
43      // TODO: Could compare two direct calls against each other if we cared to.
44      return AliasAnalysis::getModRefInfo(CS1, CS2);
45    }
46
47    virtual void getAnalysisUsage(AnalysisUsage &AU) const;
48
49    virtual bool runOnFunction(Function &F) {
50      InitializeAliasAnalysis(this);                 // set up super class
51      return false;
52    }
53
54    /// getAdjustedAnalysisPointer - This method is used when a pass implements
55    /// an analysis interface through multiple inheritance.  If needed, it
56    /// should override this to adjust the this pointer as needed for the
57    /// specified pass info.
58    virtual void *getAdjustedAnalysisPointer(const PassInfo *PI) {
59      if (PI->isPassID(&AliasAnalysis::ID))
60        return (AliasAnalysis*)this;
61      return this;
62    }
63
64  private:
65    ModRefResult AnalyzeLibCallDetails(const LibCallFunctionInfo *FI,
66                                       ImmutableCallSite CS,
67                                       const Value *P, unsigned Size);
68  };
69}  // End of llvm namespace
70
71#endif
72