Add a new interface file for the PromoteMemToReg interface in the Utils library

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@5609 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/Transforms/Utils/PromoteMemToReg.h

@@ -0,0 +1,29 @@
+//===- PromoteMemToReg.h - Promote Allocas to Scalars -----------*- C++ -*-===//
+//
+// This file exposes an interface to promote alloca instructions to SSA
+// registers, by using the SSA construction algorithm.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef TRANSFORMS_UTILS_PROMOTEMEMTOREG_H
+#define TRANSFORMS_UTILS_PROMOTEMEMTOREG_H
+
+class AllocaInst;
+class DominanceFrontier;
+#include <vector>
+
+/// isAllocaPromotable - Return true if this alloca is legal for promotion.
+/// This is true if there are only loads and stores to the alloca...
+///
+bool isAllocaPromotable(const AllocaInst *AI);
+
+/// PromoteMemToReg - Promote the specified list of alloca instructions into
+/// scalar registers, inserting PHI nodes as appropriate.  This function makes
+/// use of DominanceFrontier information.  This function does not modify the CFG
+/// of the function at all.  All allocas must be from the same function.
+///
+void PromoteMemToReg(const std::vector<AllocaInst*> &Allocas,
+                     DominanceFrontier &DF);
+
+
+#endif