Use separate random number generator for each randomization pass

src/IceCfg.h

 //===- subzero/src/IceCfg.h - Control flow graph ----------------*- C++ -*-===//
 //
 //                        The Subzero Code Generator
 //
 // This file is distributed under the University of Illinois Open Source
 // License. See LICENSE.TXT for details.
 //
 //===----------------------------------------------------------------------===//
 ///
 /// \file
@@ skipping 146 matching lines @@
   template <typename T = Assembler> T *getAssembler() const {
     return llvm::dyn_cast<T>(TargetAssembler.get());
   }
   Assembler *releaseAssembler() { return TargetAssembler.release(); }
   std::unique_ptr<VariableDeclarationList> getGlobalInits() {
     return std::move(GlobalInits);
   }
   bool hasComputedFrame() const;
   bool getFocusedTiming() const { return FocusedTiming; }
   void setFocusedTiming() { FocusedTiming = true; }
+  uint32_t getConstantBlindingCookie() const { return ConstantBlindingCookie; }
   /// @}
 
   /// Returns true if Var is a global variable that is used by the profiling
   /// code.
   static bool isProfileGlobal(const VariableDeclaration &Var);
 
   /// Passes over the CFG.
   void translate();
   /// After the CFG is fully constructed, iterate over the nodes and
   /// compute the predecessor and successor edges, in the form of
@@ skipping 63 matching lines @@
   /// code needs to be defined.
   void profileBlocks();
 
   /// Delete registered jump table placeholder instructions. This should only be
   /// called once all repointing has taken place.
   void deleteJumpTableInsts();
   /// Iterate through the registered jump tables and emit them.
   void emitJumpTables();
 
   GlobalContext *Ctx;
-  uint32_t SequenceNumber; /// output order for emission
+  uint32_t SequenceNumber;             /// output order for emission
+  uint32_t ConstantBlindingCookie = 0; /// cookie for constant blinding
   VerboseMask VMask;
   IceString FunctionName = "";
   Type ReturnType = IceType_void;
   bool IsInternalLinkage = false;
   bool HasError = false;
   bool FocusedTiming = false;
   IceString ErrorMessage = "";
   CfgNode *Entry = nullptr; /// entry basic block
   NodeList Nodes;           /// linearized node list; Entry should be first
   std::vector<IceString> IdentifierNames;
@@ skipping 22 matching lines @@
   /// other uses are possible.
   ICE_TLS_DECLARE_FIELD(const Cfg *, CurrentCfg);
 
 public:
   static void TlsInit() { ICE_TLS_INIT_FIELD(CurrentCfg); }
 };
 
 } // end of namespace Ice
 
 #endif // SUBZERO_SRC_ICECFG_H