1 //===- StringMatcher.h - Generate a matcher for input strings ---*- 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 implements the StringMatcher class.
11 //
12 //===----------------------------------------------------------------------===//
13 
14 #ifndef LLVM_TABLEGEN_STRINGMATCHER_H
15 #define LLVM_TABLEGEN_STRINGMATCHER_H
16 
17 #include "llvm/ADT/StringRef.h"
18 #include <string>
19 #include <utility>
20 #include <vector>
21 
22 namespace llvm {
23 
24 class raw_ostream;
25 
26 /// Given a list of strings and code to execute when they match, output a
27 /// simple switch tree to classify the input string.
28 ///
29 /// If a match is found, the code in Matches[i].second is executed; control must
30 /// not exit this code fragment.  If nothing matches, execution falls through.
31 class StringMatcher {
32 public:
33   using StringPair = std::pair<std::string, std::string>;
34 
35 private:
36   StringRef StrVariableName;
37   const std::vector<StringPair> &Matches;
38   raw_ostream &OS;
39 
40 public:
StringMatcher(StringRef strVariableName,const std::vector<StringPair> & matches,raw_ostream & os)41   StringMatcher(StringRef strVariableName,
42                 const std::vector<StringPair> &matches, raw_ostream &os)
43     : StrVariableName(strVariableName), Matches(matches), OS(os) {}
44 
45   void Emit(unsigned Indent = 0, bool IgnoreDuplicates = false) const;
46 
47 private:
48   bool EmitStringMatcherForChar(const std::vector<const StringPair *> &Matches,
49                                 unsigned CharNo, unsigned IndentCount,
50                                 bool IgnoreDuplicates) const;
51 };
52 
53 } // end namespace llvm
54 
55 #endif // LLVM_TABLEGEN_STRINGMATCHER_H
56