TargetLibraryInfo.h revision 398c0d8b7417dedbe244020ffb67abb54aaa1c59 
1//===-- llvm/Target/TargetLibraryInfo.h - Library information ---*- 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#ifndef LLVM_TARGET_TARGETLIBRARYINFO_H
11#define LLVM_TARGET_TARGETLIBRARYINFO_H
12
13#include "llvm/Pass.h"
14
15namespace llvm {
16  class Triple;
17
18  namespace LibFunc {
19    enum Func {
20      /// void *memset(void *b, int c, size_t len);
21      memset,
22
23      // void *memcpy(void *s1, const void *s2, size_t n);
24      memcpy,
25
26      /// void memset_pattern16(void *b, const void *pattern16, size_t len);
27      memset_pattern16,
28
29      NumLibFuncs
30    };
31  }
32
33/// TargetLibraryInfo - This immutable pass captures information about what
34/// library functions are available for the current target, and allows a
35/// frontend to disable optimizations through -fno-builtin etc.
36class TargetLibraryInfo : public ImmutablePass {
37  unsigned char AvailableArray[(LibFunc::NumLibFuncs+7)/8];
38public:
39  static char ID;
40  TargetLibraryInfo();
41  TargetLibraryInfo(const Triple &T);
42
43  /// has - This function is used by optimizations that want to match on or form
44  /// a given library function.
45  bool has(LibFunc::Func F) const {
46    return (AvailableArray[F/8] & (1 << (F&7))) != 0;
47  }
48
49  /// setUnavailable - this can be used by whatever sets up TargetLibraryInfo to
50  /// ban use of specific library functions.
51  void setUnavailable(LibFunc::Func F) {
52    AvailableArray[F/8] &= ~(1 << (F&7));
53  }
54
55  void setAvailable(LibFunc::Func F) {
56    AvailableArray[F/8] |= 1 << (F&7);
57  }
58};
59
60} // end namespace llvm
61
62#endif
63