Merge experimental/a64 to bleeding_edge.

src/platform-linux.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 35 matching lines @@
 #include <sys/stat.h>   // open
 #include <fcntl.h>      // open
 #include <unistd.h>     // sysconf
 #include <strings.h>    // index
 #include <errno.h>
 #include <stdarg.h>
 
 // GLibc on ARM defines mcontext_t has a typedef for 'struct sigcontext'.
 // Old versions of the C library <signal.h> didn't define the type.
 #if defined(__ANDROID__) && !defined(__BIONIC_HAVE_UCONTEXT_T) && \
-    defined(__arm__) && !defined(__BIONIC_HAVE_STRUCT_SIGCONTEXT)
+    (defined(__arm__) || defined(__aarch64__)) && \
+    !defined(__BIONIC_HAVE_STRUCT_SIGCONTEXT)
 #include <asm/sigcontext.h>
 #endif
 
 #if defined(LEAK_SANITIZER)
 #include <sanitizer/lsan_interface.h>
 #endif
 
 #undef MAP_TYPE
 
 #include "v8.h"
@@ skipping 381 matching lines @@
 #endif
   return munmap(base, size) == 0;
 }
 
 
 bool VirtualMemory::HasLazyCommits() {
   return true;
 }
 
 } }  // namespace v8::internal