Make 'SaveAndRestore' and friends reusable classes in libAnalysis.

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@76795 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 45 insertions, 12 deletions

diff --git a/include/clang/Analysis/Support/SaveAndRestore.h b/include/clang/Analysis/Support/SaveAndRestore.h
new file mode 100644
index 0000000000..0487c6f524
--- /dev/null
+++ b/include/clang/Analysis/Support/SaveAndRestore.h
@@ -0,0 +1,44 @@
+//===-- SaveAndRestore.h - Utility  -------------------------------*- C++ -*-=//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+//  This file provides utility classes that uses RAII to save and restore
+//  values.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CLANG_ANALYSIS_SAVERESTORE
+#define LLVM_CLANG_ANALYSIS_SAVERESTORE
+
+namespace clang {
+  
+// SaveAndRestore - A utility class that uses RAII to save and restore
+//  the value of a variable.
+template<typename T>
+struct SaveAndRestore {
+  SaveAndRestore(T& x) : X(x), old_value(x) {}
+  ~SaveAndRestore() { X = old_value; }
+  T get() { return old_value; }
+private:  
+  T& X;
+  T old_value;
+};
+
+// SaveOr - Similar to SaveAndRestore.  Operates only on bools; the old
+//  value of a variable is saved, and during the dstor the old value is
+//  or'ed with the new value.
+struct SaveOr {
+  SaveOr(bool& x) : X(x), old_value(x) { x = false; }
+  ~SaveOr() { X |= old_value; }
+private:
+  bool& X;
+  const bool old_value;
+};
+  
+}
+#endif
\ No newline at end of file
diff --git a/lib/Analysis/CFG.cpp b/lib/Analysis/CFG.cpp
index 79ca8114a7..4c2ecb92f6 100644
--- a/lib/Analysis/CFG.cpp
+++ b/lib/Analysis/CFG.cpp
@@ -12,6 +12,7 @@
 //
 //===----------------------------------------------------------------------===//
 
+#include "clang/Analysis/Support/SaveAndRestore.h"
 #include "clang/Analysis/CFG.h"
 #include "clang/AST/StmtVisitor.h"
 #include "clang/AST/PrettyPrinter.h"
@@ -27,18 +28,6 @@ using namespace clang;
 
 namespace {
 
-// SaveAndRestore - A utility class that uses RIIA to save and restore
-//  the value of a variable.
-template<typename T>
-struct VISIBILITY_HIDDEN SaveAndRestore {
-  SaveAndRestore(T& x) : X(x), old_value(x) {}
-  ~SaveAndRestore() { X = old_value; }
-  T get() { return old_value; }
-
-  T& X;
-  T old_value;
-};
-
 static SourceLocation GetEndLoc(Decl* D) {
   if (VarDecl* VD = dyn_cast<VarDecl>(D))
     if (Expr* Ex = VD->getInit())