Prepares for arm64 cross-build.

runtime/platform/globals.h

 // 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.
 
 #ifndef PLATFORM_GLOBALS_H_
 #define PLATFORM_GLOBALS_H_
 
 // __STDC_FORMAT_MACROS has to be defined before including <inttypes.h> to
 // enable platform independent printf format specifiers.
 #ifndef __STDC_FORMAT_MACROS
@@ skipping 149 matching lines @@
     reinterpret_cast<simd_value_t *>(addr)->data_[1] = value.data_[1];         \
     reinterpret_cast<simd_value_t *>(addr)->data_[2] = value.data_[2];         \
     reinterpret_cast<simd_value_t *>(addr)->data_[3] = value.data_[3];         \
   } while (0)
 
 #elif defined(__MIPSEL__)
 #define HOST_ARCH_MIPS 1
 #define ARCH_IS_32_BIT 1
 #define kFpuRegisterSize 8
 typedef double fpu_register_t;
+#elif defined(__aarch64__)
+#define HOST_ARCH_ARM64 1
+#define ARCH_IS_64_BIT 1
+#define kFpuRegisterSize 16
+typedef simd128_value_t fpu_register_t;
 #else
 #error Architecture was not detected as supported by Dart.
 #endif
 
 // DART_FORCE_INLINE strongly hints to the compiler that a function should
 // be inlined. Your function is not guaranteed to be inlined but this is
 // stronger than just using "inline".
 // See: http://msdn.microsoft.com/en-us/library/z8y1yy88.aspx for an
 // explanation of some the cases when a function can never be inlined.
 #ifdef _MSC_VER
@@ skipping 316 matching lines @@
 // N.B.: As the GCC manual states, "[s]ince non-static C++ methods
 // have an implicit 'this' argument, the arguments of such methods
 // should be counted from two, not one."
 #define PRINTF_ATTRIBUTE(string_index, first_to_check) \
   __attribute__((__format__(__printf__, string_index, first_to_check)))
 #else
 #define PRINTF_ATTRIBUTE(string_index, first_to_check)
 #endif
 
 #endif  // PLATFORM_GLOBALS_H_