LibCallAliasAnalysis.h revision b877a1f5458e26bb1020d4a07637d898559fc8a7 
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, 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(CallSite CS, Value *P, unsigned Size);
39
40    ModRefResult getModRefInfo(CallSite CS1, CallSite CS2) {
41      // TODO: Could compare two direct calls against each other if we cared to.
42      return AliasAnalysis::getModRefInfo(CS1,CS2);
43    }
44
45    virtual void getAnalysisUsage(AnalysisUsage &AU) const;
46
47    virtual bool runOnFunction(Function &F) {
48      InitializeAliasAnalysis(this);                 // set up super class
49      return false;
50    }
51
52    /// hasNoModRefInfoForCalls - We can provide mod/ref information against
53    /// non-escaping allocations.
54    virtual bool hasNoModRefInfoForCalls() const { return false; }
55  private:
56    ModRefResult AnalyzeLibCallDetails(const LibCallFunctionInfo *FI,
57                                       CallSite CS, Value *P, unsigned Size);
58  };
59}  // End of llvm namespace
60
61#endif
62