Checkin new alias analysis infrastructure

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@3464 91177308-0d34-0410-b5e6-96231b3b80d8

include/llvm/Analysis/BasicAliasAnalysis.h

@@ -0,0 +1,48 @@
+//===- llvm/Analysis/BasicAliasAnalysis.h - Alias Analysis Impl -*- C++ -*-===//
+//
+// This file defines the generic AliasAnalysis interface, which is used as the
+// common interface used by all clients of alias analysis information, and
+// implemented by all alias analysis implementations.
+//
+// Implementations of this interface must implement the various virtual methods,
+// which automatically provides functionality for the entire suite of client
+// APIs.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_ANALYSIS_BASIC_ALIAS_ANALYSIS_H
+#define LLVM_ANALYSIS_BASIC_ALIAS_ANALYSIS_H
+
+#include "llvm/Analysis/AliasAnalysis.h"
+#include "llvm/Pass.h"
+
+struct BasicAliasAnalysis : public FunctionPass, public AliasAnalysis {
+  
+  // Pass Implementation stuff.  This isn't much of a pass.
+  //
+  bool runOnFunction(Function &) { return false; }
+    
+  // getAnalysisUsage - Does not modify anything.
+  //
+  virtual void getAnalysisUsage(AnalysisUsage &AU) const {
+    AU.setPreservesAll();
+  }
+  
+  // alias - This is the only method here that does anything interesting...
+  //
+  Result alias(const Value *V1, const Value *V2) const;
+    
+  // canCallModify - We are not interprocedural, so we do nothing exciting.
+  //
+  Result canCallModify(const CallInst &CI, const Value *Ptr) const {
+    return MayAlias;
+  }
+    
+  // canInvokeModify - We are not interprocedural, so we do nothing exciting.
+  //
+  Result canInvokeModify(const InvokeInst &I, const Value *Ptr) const {
+    return MayAlias;  // We are not interprocedural
+  }
+};
+
+#endif