factor the snazzy string matcher code that Daniel hates

out of AsmMatcherEmitter.cpp into its own class.

llvm-svn: 113137

1 files changed, 54 insertions, 0 deletions

diff --git a/llvm/utils/TableGen/StringMatcher.h b/llvm/utils/TableGen/StringMatcher.h
new file mode 100644
index 00000000000..79878202943
--- /dev/null
+++ b/llvm/utils/TableGen/StringMatcher.h
@@ -0,0 +1,54 @@
+//===- StringMatcher.h - Generate a matcher for input strings ---*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the StringMatcher class.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef STRINGMATCHER_H
+#define STRINGMATCHER_H
+
+#include <vector>
+#include <string>
+#include <utility>
+#include "llvm/ADT/StringRef.h"
+
+namespace llvm {
+  class raw_ostream;
+  
+/// StringMatcher - Given a list of strings and code to execute when they match,
+/// output a simple switch tree to classify the input string.
+/// 
+/// If a match is found, the code in Vals[i].second is executed; control must
+/// not exit this code fragment.  If nothing matches, execution falls through.
+///
+class StringMatcher {
+public:
+  typedef std::pair<std::string, std::string> StringPair;
+private:
+  StringRef StrVariableName;
+  const std::vector<StringPair> &Matches;
+  raw_ostream &OS;
+  
+public:
+  StringMatcher(StringRef strVariableName, 
+                const std::vector<StringPair> &matches, raw_ostream &os)
+    : StrVariableName(strVariableName), Matches(matches), OS(os) {}
+  
+  void Emit() const;
+  
+  
+private:
+  bool EmitStringMatcherForChar(const std::vector<const StringPair*> &Matches,
+                                unsigned CharNo, unsigned IndentCount) const;
+};
+
+} // end llvm namespace.
+
+#endif