Allow snapshots to be generated without using vfp3 code on arm.

SConstruct

 # Copyright 2011 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 135 matching lines @@
       'unalignedaccesses:off' : {
         'CPPDEFINES' : ['CAN_USE_UNALIGNED_ACCESSES=0']
       },
       'armeabi:soft' : {
         'CPPDEFINES' : ['USE_EABI_HARDFLOAT=0'],
         'simulator:none': {
           'CCFLAGS':     ['-mfloat-abi=soft'],
         }
       },
       'armeabi:softfp' : {
-        'CPPDEFINES' : ['USE_EABI_HARDFLOAT=0', 'CAN_USE_VFP_INSTRUCTIONS'],
+        'CPPDEFINES' : ['USE_EABI_HARDFLOAT=0'],
+        'vfp3:on': {
+          'CPPDEFINES' : ['CAN_USE_VFP_INSTRUCTIONS']
+        },
         'simulator:none': {
           'CCFLAGS':     ['-mfloat-abi=softfp'],
         }
       },
       'armeabi:hard' : {
-        'CPPDEFINES' : ['USE_EABI_HARDFLOAT=1', 'CAN_USE_VFP_INSTRUCTIONS'],
+        'CPPDEFINES' : ['USE_EABI_HARDFLOAT=1'],
+        'vfp3:on': {
+          'CPPDEFINES' : ['CAN_USE_VFP_INSTRUCTIONS']
+        },
         'simulator:none': {
           'CCFLAGS':     ['-mfloat-abi=hard'],
         }
       }
     },
     'simulator:arm': {
       'CCFLAGS':      ['-m32'],
       'LINKFLAGS':    ['-m32'],
     },
     'arch:mips': {
@@ skipping 316 matching lines @@
           'CCFLAGS':     ['-mfloat-abi=soft'],
         }
       },
       'armeabi:softfp' : {
         'CPPDEFINES' : ['USE_EABI_HARDFLOAT=0'],
         'simulator:none': {
           'CCFLAGS':     ['-mfloat-abi=softfp'],
         }
       },
       'armeabi:hard' : {
-        'CPPDEFINES' : ['USE_EABI_HARDFLOAT=1', 'CAN_USE_VFP_INSTRUCTIONS'],
+        'CPPDEFINES' : ['USE_EABI_HARDFLOAT=1'],
+        'vfp3:on': {
+          'CPPDEFINES' : ['CAN_USE_VFP_INSTRUCTIONS']
+        },
         'simulator:none': {
           'CCFLAGS':     ['-mfloat-abi=hard'],
         }
       }
     },
     'arch:ia32': {
       'CCFLAGS':      ['-m32'],
       'LINKFLAGS':    ['-m32']
     },
     'arch:x64': {
@@ skipping 522 matching lines @@
   'mips_arch_variant': {
     'values': ['mips32r2', 'mips32r1'],
     'default': 'mips32r2',
     'help': 'mips variant'
   },
   'compress_startup_data': {
     'values': ['off', 'bz2'],
     'default': 'off',
     'help': 'compress startup data (snapshot) [Linux only]'
   },
+  'vfp3': {
+    'values': ['on', 'off'],
+    'default': 'on',
+    'help': 'use vfp3 instructions when building the snapshot [Arm only]'
+  },
+
 }
 
 ALL_OPTIONS = dict(PLATFORM_OPTIONS, **SIMPLE_OPTIONS)
 
 
 def AddOptions(options, result):
   guess_env = Environment(options=result)
   for (name, option) in options.iteritems():
     if 'guess' in option:
       # Option has a guess function
@@ skipping 424 matching lines @@
 # version of scons.  Also, there's a bug in some revisions that
 # doesn't allow this flag to be set, so we swallow any exceptions.
 # Lovely.
 try:
   SetOption('warn', 'no-deprecated')
 except:
   pass
 
 
 Build()