Align code by 32 bytes to reduce benchmark flakiness on Intel CPUs.

runtime/vm/os_linux.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/globals.h"
 #if defined(TARGET_OS_LINUX)
 
 #include "vm/os.h"
 
 #include <errno.h>  // NOLINT
@@ skipping 340 matching lines @@
   // testing purposes.
   // Flags::DebugIsInt("stackalign", &alignment);
   ASSERT(Utils::IsPowerOfTwo(alignment));
   ASSERT(alignment >= kMinimumAlignment);
   return alignment;
 }
 
 
 word OS::PreferredCodeAlignment() {
 #if defined(TARGET_ARCH_IA32) || defined(TARGET_ARCH_X64)
-  const int kMinimumAlignment = 16;
+  const int kMinimumAlignment = 32;
 #elif defined(TARGET_ARCH_ARM) || defined(TARGET_ARCH_MIPS)
   // TODO(regis): Verify alignment constraints on MIPS.
   const int kMinimumAlignment = 16;
 #else
 #error Unsupported architecture.
 #endif
   word alignment = kMinimumAlignment;
   // TODO(5411554): Allow overriding default code alignment for
   // testing purposes.
   // Flags::DebugIsInt("codealign", &alignment);
@@ skipping 143 matching lines @@
 }
 
 
 void OS::Exit(int code) {
   exit(code);
 }
 
 }  // namespace dart
 
 #endif  // defined(TARGET_OS_LINUX)