A mechanism to identify/forbid/"rewrite" non-temporal instructions (and other)

src/trusted/validator_ragel/dfa_validate_common.h

 /*
  * Copyright (c) 2012 The Native Client Authors. All rights reserved.
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 /*
  * This file contains common parts of x86-32 and x86-64 internals (inline
  * and static functions and defines).
  */
@@ skipping 13 matching lines @@
  *   3:   49 8d 34 37             lea    (%r15,%rsi,1),%rsi
  *   7:   40 89 ff                rex mov    %edi,%edi
  *   a:   49 8d 3c 3f             lea    (%r15,%rdi,1),%rdi
  *   e:   f2 48 a7                repnz cmpsq %es:(%rdi),%ds:(%rsi)
  */
 #define MAX_INSTRUCTION_LENGTH 17
 
 Bool NaClDfaProcessValidationError(const uint8_t *begin, const uint8_t *end,
                                    uint32_t info, void *callback_data);
 
-Bool NaClDfaStubOutCPUUnsupportedInstruction(const uint8_t *begin,
-                                             const uint8_t *end,
-                                             uint32_t info,
-                                             void *callback_data);
+struct StubOutCallbackData {
+  uint32_t flags;
+  int did_rewrite;
+};
+
+Bool NaClDfaStubOutUnsupportedInstruction(const uint8_t *begin,
+                                          const uint8_t *end,
+                                          uint32_t info,
+                                          void *callback_data);
+
 struct CodeCopyCallbackData {
   NaClCopyInstructionFunc copy_func;
   /* Difference between addresses: dest - src.  */
   ptrdiff_t existing_minus_new;
 };
 
 Bool NaClDfaProcessCodeCopyInstruction(const uint8_t *begin_new,
                                        const uint8_t *end_new,
                                        uint32_t info,
                                        void *callback_data);
 
 /* Check whether instruction is stubouted because it is not supported by current
    CPU.  */
 Bool NaClDfaCodeReplacementIsStubouted(const uint8_t *begin_existing,
                                        size_t instruction_length);
 
 #endif /* NATIVE_CLIENT_SRC_TRUSTED_VALIDATOR_RAGEL_DFA_VALIDATE_COMMON_H_ */