Rewrite non-temporal instructions

src/trusted/validator_ragel/dfa_validate_64.c

Index: src/trusted/validator_ragel/dfa_validate_64.c
diff --git a/src/trusted/validator_ragel/dfa_validate_64.c b/src/trusted/validator_ragel/dfa_validate_64.c
index f91d36fe95be581edacec83c3c3a303e2dec2f6e..3fd2453e7cfd81516292dcf93c9def26d983f44e 100644
--- a/src/trusted/validator_ragel/dfa_validate_64.c
+++ b/src/trusted/validator_ragel/dfa_validate_64.c
@@ -40,8 +40,14 @@ static NaClValidationStatus ApplyDfaValidator_x86_64(
   enum NaClValidationStatus status = NaClValidationFailed;
   void *query = NULL;
   struct StubOutCallbackData callback_data;
+  /* For revalidation */
+  struct StubOutCallbackData reval_callback_data;
+  Bool reval_result = FALSE;
+
   callback_data.flags = flags;
   callback_data.did_rewrite = 0;
+  reval_callback_data.flags = flags;
+  reval_callback_data.did_rewrite = 0;
   UNREFERENCED_PARAMETER(guest_addr);
 
   if (stubout_mode)
@@ -76,8 +82,19 @@ static NaClValidationStatus ApplyDfaValidator_x86_64(
   } else {
     if (ValidateChunkAMD64(data, size, 0 /*options*/, cpu_features,
                            NaClDfaStubOutUnsupportedInstruction,
-                           &callback_data))
-      status = NaClValidationSucceeded;
+                           &callback_data)) {
+      /* If code is rewritten, revalidate. */
+      if (callback_data.did_rewrite == 1) {
+        reval_result = ValidateChunkAMD64(data, size, 0 /*options*/,
+                                          cpu_features,
+                                          NaClDfaStubOutUnsupportedInstruction,
+                                          &reval_callback_data);
+        if (reval_result && reval_callback_data.did_rewrite == 0)
+          status = NaClValidationSucceeded;
+      } else {
+        status = NaClValidationSucceeded;
+      }
+    }
   }
 
   if (status != NaClValidationSucceeded && errno == ENOMEM)