Import LLVM, at r72732.

1 files changed, 49 insertions, 0 deletions

diff --git a/include/llvm/Transforms/Utils/UnifyFunctionExitNodes.h b/include/llvm/Transforms/Utils/UnifyFunctionExitNodes.h
new file mode 100644
index 0000000..c2d0993
--- /dev/null
+++ b/include/llvm/Transforms/Utils/UnifyFunctionExitNodes.h
@@ -0,0 +1,49 @@
+//===-- UnifyFunctionExitNodes.h - Ensure fn's have one return --*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This pass is used to ensure that functions have at most one return and one
+// unwind instruction in them.  Additionally, it keeps track of which node is
+// the new exit node of the CFG.  If there are no return or unwind instructions
+// in the function, the getReturnBlock/getUnwindBlock methods will return a null
+// pointer.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_TRANSFORMS_UNIFYFUNCTIONEXITNODES_H
+#define LLVM_TRANSFORMS_UNIFYFUNCTIONEXITNODES_H
+
+#include "llvm/Pass.h"
+
+namespace llvm {
+
+struct UnifyFunctionExitNodes : public FunctionPass {
+  BasicBlock *ReturnBlock, *UnwindBlock, *UnreachableBlock;
+public:
+  static char ID; // Pass identification, replacement for typeid
+  UnifyFunctionExitNodes() : FunctionPass(&ID),
+                             ReturnBlock(0), UnwindBlock(0) {}
+
+  // We can preserve non-critical-edgeness when we unify function exit nodes
+  virtual void getAnalysisUsage(AnalysisUsage &AU) const;
+
+  // getReturn|Unwind|UnreachableBlock - Return the new single (or nonexistant)
+  // return, unwind, or unreachable  basic blocks in the CFG.
+  //
+  BasicBlock *getReturnBlock() const { return ReturnBlock; }
+  BasicBlock *getUnwindBlock() const { return UnwindBlock; }
+  BasicBlock *getUnreachableBlock() const { return UnreachableBlock; }
+
+  virtual bool runOnFunction(Function &F);
+};
+
+Pass *createUnifyFunctionExitNodesPass();
+
+} // End llvm namespace
+
+#endif