Add constant blinding/pooling option for X8632 code translation

src/IceGlobalContext.h

Index: src/IceGlobalContext.h
diff --git a/src/IceGlobalContext.h b/src/IceGlobalContext.h
index 763a75b487ced3554f3bf53127106f792eabdf31..a632253f801fb70e7eee71349b8a093f4be91d1f 100644
--- a/src/IceGlobalContext.h
+++ b/src/IceGlobalContext.h
@@ -72,7 +72,8 @@ class GlobalContext {
   X("Regs Saved  ", RegsSaved)                                                 \
   X("Frame Bytes ", FrameByte)                                                 \
   X("Spills      ", NumSpills)                                                 \
-  X("Fills       ", NumFills)
+  X("Fills       ", NumFills)                                                  \
+  X("R/P Imms    ", NumRPImms)
     //#define X(str, tag)
 
   public:
@@ -263,6 +264,15 @@ public:
     Tls->StatsCumulative.update(CodeStats::CS_NumFills);
   }
 
+  // Number of Randomized or Pooled Immediates
+  void statsUpdateRPImms() {
+    if (!getFlags().getDumpStats())
+      return;
+    ThreadContext *Tls = ICE_TLS_GET_FIELD(TLS);
+    Tls->StatsFunction.update(CodeStats::CS_NumRPImms);
+    Tls->StatsCumulative.update(CodeStats::CS_NumRPImms);
+  }
+
   // These are predefined TimerStackIdT values.
   enum TimerStackKind { TSK_Default = 0, TSK_Funcs, TSK_Num };
 
@@ -391,6 +401,21 @@ public:
     return Match.empty() || Match == SymbolName;
   }
 
+  // Return the randomization cookie for diversification.
+  // Initialize the cookie if necessary
+  uint32_t getRandomizationCookie() {
+    if (RandomizationCookie != 0)
+      return RandomizationCookie;

[JF, 2015/06/17 11:29:18]

This technically needs to be an atomic read, though it can be a relaxed atomic
read. This will be a problem when running as a pexe because relaxed atomics are
upgraded to seq_cst.

Could this not be synchronized at all, and instead initialized once before
IceGlobalContext is created?

[qining, 2015/06/17 18:20:36]

Do you mean using std::atomic<int> for the randomization cookie? You are right
that this cookie just needs to be initialized once. Reading it won't cause any
synchronization problem. I'm think if I should initialize it in the constructor
of IceGlobalContext. I always hope to confine this variable in smaller scope.

+    RandomizationCookieLock.lock();
+    while (RandomizationCookie == 0) {
+      RandomNumberGenerator &RNG = getRNG();
+      RandomizationCookie = (uint32_t)RNG.next(
+          (uint64_t)std::numeric_limits<uint32_t>::max() + 1);
+    }
+    RandomizationCookieLock.unlock();
+    return RandomizationCookie;
+  }

[qining, 2015/06/17 04:28:55]

Method to initialize the randomization cookie and get the cookie

+
 private:
   // Try to ensure mutexes are allocated on separate cache lines.
 
@@ -460,6 +485,11 @@ private:
   typedef llvm::SmallVector<char, 32> ManglerVector;
   void incrementSubstitutions(ManglerVector &OldName) const;
 
+  // Randomization Cookie
+  // Managed by getRandomizationCookie()
+  GlobalLockType RandomizationCookieLock;
+  uint32_t RandomizationCookie;

[qining, 2015/06/17 04:28:55]

Move the Randomization cookie to here from TargetX8632.

+
 public:
   static void TlsInit() { ICE_TLS_INIT_FIELD(TLS); }
 };