MIPS64: Add big-endian support for mips64.

src/base/build_config.h

 // Copyright 2014 the V8 project 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 V8_BASE_BUILD_CONFIG_H_
 #define V8_BASE_BUILD_CONFIG_H_
 
 #include "include/v8config.h"
 
 // Processor architecture detection.  For more info on what's defined, see:
@@ skipping 146 matching lines @@
 #define V8_TARGET_LITTLE_ENDIAN 1
 #elif V8_TARGET_ARCH_ARM64
 #define V8_TARGET_LITTLE_ENDIAN 1
 #elif V8_TARGET_ARCH_MIPS
 #if defined(__MIPSEB__)
 #define V8_TARGET_BIG_ENDIAN 1
 #else
 #define V8_TARGET_LITTLE_ENDIAN 1
 #endif
 #elif V8_TARGET_ARCH_MIPS64
+#if defined(__MIPSEB__) || defined(V8_TARGET_ARCH_MIPS64_BE)
+#define V8_TARGET_BIG_ENDIAN 1
+#else
 #define V8_TARGET_LITTLE_ENDIAN 1
+#endif
 #elif V8_TARGET_ARCH_X87
 #define V8_TARGET_LITTLE_ENDIAN 1
 #elif V8_TARGET_ARCH_PPC_LE
 #define V8_TARGET_LITTLE_ENDIAN 1
 #elif V8_TARGET_ARCH_PPC_BE
 #define V8_TARGET_BIG_ENDIAN 1
 #else
 #error Unknown target architecture endianness
 #endif
 
 // Number of bits to represent the page size for paged spaces. The value of 20
 // gives 1Mb bytes per page.
 #if V8_HOST_ARCH_PPC && V8_TARGET_ARCH_PPC && V8_OS_LINUX
 // Bump up for Power Linux due to larger (64K) page size.
 const int kPageSizeBits = 22;
 #else
 const int kPageSizeBits = 20;
 #endif
 
 #endif  // V8_BASE_BUILD_CONFIG_H_