Disable CFI on a few src/cc methods for perf reasons.

base/compiler_specific.h

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #ifndef BASE_COMPILER_SPECIFIC_H_
 #define BASE_COMPILER_SPECIFIC_H_
 
 #include "build/build_config.h"
 
 #if defined(COMPILER_MSVC)
@@ skipping 151 matching lines @@
 // If any bits are uninitialized, crash with an MSan report.
 // Use this to sanitize data which MSan won't be able to track, e.g. before
 // passing data to another process via shared memory.
 #define MSAN_CHECK_MEM_IS_INITIALIZED(p, size) \
     __msan_check_mem_is_initialized(p, size)
 #else  // MEMORY_SANITIZER
 #define MSAN_UNPOISON(p, size)
 #define MSAN_CHECK_MEM_IS_INITIALIZED(p, size)
 #endif  // MEMORY_SANITIZER
 
+// DISABLE_CFI_PERF -- Disable Control Flow Integrity for perf reasons.
+#if !defined(DISABLE_CFI_PERF)
+#if defined(__clang__)
+#define DISABLE_CFI_PERF __attribute__((no_sanitize("cfi")))
+#else
+#define DISABLE_CFI_PERF
+#endif
+#endif
+
 // Macro useful for writing cross-platform function pointers.
 #if !defined(CDECL)
 #if defined(OS_WIN)
 #define CDECL __cdecl
 #else  // defined(OS_WIN)
 #define CDECL
 #endif  // defined(OS_WIN)
 #endif  // !defined(CDECL)
 
 // Macro for hinting that an expression is likely to be false.
 #if !defined(UNLIKELY)
 #if defined(COMPILER_GCC)
 #define UNLIKELY(x) __builtin_expect(!!(x), 0)
 #else
 #define UNLIKELY(x) (x)
 #endif  // defined(COMPILER_GCC)
 #endif  // !defined(UNLIKELY)
 
 // Compiler feature-detection.
 // clang.llvm.org/docs/LanguageExtensions.html#has-feature-and-has-extension
 #if defined(__has_feature)
 #define HAS_FEATURE(FEATURE) __has_feature(FEATURE)
 #else
 #define HAS_FEATURE(FEATURE) 0
 #endif
 
 #endif  // BASE_COMPILER_SPECIFIC_H_