ARM: add AArch32 support and new vcvt instructions

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 37 matching lines @@
 #if defined(__ARM_ARCH_7A__) || \
     defined(__ARM_ARCH_7R__) || \
     defined(__ARM_ARCH_7__)
 # define CAN_USE_ARMV7_INSTRUCTIONS 1
 # ifndef CAN_USE_VFP3_INSTRUCTIONS
 #  define CAN_USE_VFP3_INSTRUCTIONS
 # endif
 #endif
 
 
+#if defined(__ARM_ARCH_8A__) || \
+    defined(__ARM_ARCH_8R__) || \
+    defined(__ARM_ARCH_8__)
+# define CAN_USE_ARMV8_INSTRUCTIONS 1
+# ifndef CAN_USE_ARMV7_INSTRUCTIONS
+#  define CAN_USE_ARMV7_INSTRUCTIONS 1
+# endif
+# ifndef CAN_USE_VFP3_INSTRUCTIONS
+#  define CAN_USE_VFP3_INSTRUCTIONS
+# endif
+# ifndef CAN_USE_VFP32DREGS
+#  define CAN_USE_VFP32DREGS
+# endif
+# ifndef CAN_USE_NEON
+#  define CAN_USE_NEON
+#endif
+#endif
+
+
 // Target architecture detection. This may be set externally. If not, detect
 // in the same way as the host architecture, that is, target the native
 // environment as presented by the compiler.
 #if !V8_TARGET_ARCH_X64 && !V8_TARGET_ARCH_IA32 && !V8_TARGET_ARCH_X87 && \
     !V8_TARGET_ARCH_ARM && !V8_TARGET_ARCH_ARM64 && !V8_TARGET_ARCH_MIPS
 #if defined(_M_X64) || defined(__x86_64__)
 #define V8_TARGET_ARCH_X64 1
 #elif defined(_M_IX86) || defined(__i386__)
 #define V8_TARGET_ARCH_IA32 1
 #elif defined(__AARCH64EL__)
@@ skipping 43 matching lines @@
 #define V8_TARGET_LITTLE_ENDIAN 1
 #else
 #error Unknown target architecture endianness
 #endif
 
 #if V8_OS_MACOSX || defined(__FreeBSD__) || defined(__OpenBSD__)
 #define USING_BSD_ABI
 #endif
 
 #endif  // V8_BASE_BUILD_CONFIG_H_