[Arm]: Simplify compile-time Arm feature detection.

build/toolchain.gypi

 # Copyright 2013 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 29 matching lines @@
     # TODO(bradchen): get rid of nacl_target_arch when someday
     # NaCl V8 builds stop using the ARM simulator
     'nacl_target_arch%': 'none',     # must be set externally
 
     # Setting 'v8_can_use_vfp32dregs' to 'true' will cause V8 to use the VFP
     # registers d16-d31 in the generated code, both in the snapshot and for the
     # ARM target. Leaving the default value of 'false' will avoid the use of
     # these registers in the snapshot and use CPU feature probing when running
     # on the target.
     'v8_can_use_vfp32dregs%': 'false',
-    'arm_test%': 'off',
+    'arm_test_noprobe%': 'off',
 
     # Similar to vfp but on MIPS.
     'v8_can_use_fpu_instructions%': 'true',
 
     # Similar to the ARM hard float ABI but on MIPS.
     'v8_use_mips_abi_hardfloat%': 'true',
 
     # Default arch variant for MIPS.
     'mips_arch_variant%': 'mips32r2',
 
@@ skipping 21 matching lines @@
 
     # Allow to suppress the array bounds warning (default is no suppression).
     'wno_array_bounds%': '',
   },
   'target_defaults': {
     'conditions': [
       ['v8_target_arch=="arm"', {
         'defines': [
           'V8_TARGET_ARCH_ARM',
         ],
+        'conditions': [
+          [ 'arm_version==7 or arm_version=="default"', {
+            'defines': [
+              'CAN_USE_ARMV7_INSTRUCTIONS',
+            ],
+          }],
+          [ 'arm_fpu=="vfpv3-d16" or arm_fpu=="default"', {
+            'defines': [
+              'CAN_USE_VFP3_INSTRUCTIONS',
+            ],
+          }],
+          [ 'arm_fpu=="vfpv3"', {
+            'defines': [
+              'CAN_USE_VFP3_INSTRUCTIONS',
+              'CAN_USE_VFP32DREGS',
+            ],
+          }],
+          [ 'arm_fpu=="neon"', {
+            'defines': [
+              'CAN_USE_VFP3_INSTRUCTIONS',
+              'CAN_USE_VFP32DREGS',
+              'CAN_USE_NEON',
+            ],
+          }],
+          [ 'arm_test_noprobe=="on"', {
+            'defines': [
+              'ARM_TEST_NO_FEATURE_PROBE',
+            ],
+          }],
+        ],
         'target_conditions': [
           ['_toolset=="host"', {
             'variables': {
               'armcompiler': '<!($(echo ${CXX_host:-$(which g++)}) -v 2>&1 | grep -q "^Target: arm" && echo "yes" || echo "no")',
             },
             'conditions': [
               ['armcompiler=="yes"', {
                 'conditions': [
                   [ 'arm_version==7', {
                     'cflags': ['-march=armv7-a',],
                   }],
                   [ 'arm_version==7 or arm_version=="default"', {
                     'conditions': [
                       [ 'arm_fpu!="default"', {
                         'cflags': ['-mfpu=<(arm_fpu)',],
                       }],
                     ],
                   }],
                   [ 'arm_float_abi!="default"', {
                     'cflags': ['-mfloat-abi=<(arm_float_abi)',],
                   }],
                   [ 'arm_thumb==1', {
                     'cflags': ['-mthumb',],
                   }],
                   [ 'arm_thumb==0', {
                     'cflags': ['-marm',],
                   }],
-                  [ 'arm_test=="on"', {
-                    'defines': [
-                      'ARM_TEST',
-                    ],
-                  }],
                 ],
               }, {
                 # armcompiler=="no"
                 'conditions': [
-                  [ 'arm_version==7 or arm_version=="default"', {
-                    'defines': [
-                      'CAN_USE_ARMV7_INSTRUCTIONS=1',
-                    ],
-                    'conditions': [
-                      [ 'arm_fpu=="default"', {
-                        'defines': [
-                          'CAN_USE_VFP3_INSTRUCTIONS',
-                        ],
-                      }],
-                      [ 'arm_fpu=="vfpv3-d16"', {
-                        'defines': [
-                          'CAN_USE_VFP3_INSTRUCTIONS',
-                        ],
-                      }],
-                      [ 'arm_fpu=="vfpv3"', {
-                        'defines': [
-                          'CAN_USE_VFP3_INSTRUCTIONS',
-                          'CAN_USE_VFP32DREGS',
-                        ],
-                      }],
-                      [ 'arm_fpu=="neon"', {
-                        'defines': [
-                          'CAN_USE_VFP3_INSTRUCTIONS',
-                          'CAN_USE_VFP32DREGS',
-                          'CAN_USE_NEON',
-                        ],
-                      }],
-                    ],
-                  }],
                   [ 'arm_float_abi=="hard"', {
                     'defines': [
                       'USE_EABI_HARDFLOAT=1',
                     ],
                   }],
                   [ 'arm_float_abi=="softfp" or arm_float_abi=="default"', {
                     'defines': [
                       'USE_EABI_HARDFLOAT=0',
                     ],
                   }],
                 ],
-                'defines': [
-                  'ARM_TEST',
-                ],
               }],
             ],
           }],  # _toolset=="host"
           ['_toolset=="target"', {
             'variables': {
               'armcompiler': '<!($(echo ${CXX_target:-<(CXX)}) -v 2>&1 | grep -q "^Target: arm" && echo "yes" || echo "no")',
             },
             'conditions': [
               ['armcompiler=="yes"', {
                 'conditions': [
                   [ 'arm_version==7', {
                     'cflags': ['-march=armv7-a',],
                   }],
                   [ 'arm_version==7 or arm_version=="default"', {
                     'conditions': [
                       [ 'arm_fpu!="default"', {
                         'cflags': ['-mfpu=<(arm_fpu)',],
                       }],
                     ],
                   }],
                   [ 'arm_float_abi!="default"', {
                     'cflags': ['-mfloat-abi=<(arm_float_abi)',],
                   }],
                   [ 'arm_thumb==1', {
                     'cflags': ['-mthumb',],
                   }],
                   [ 'arm_thumb==0', {
                     'cflags': ['-marm',],
                   }],
-                  [ 'arm_test=="on"', {
-                    'defines': [
-                      'ARM_TEST',
-                    ],
-                    'conditions': [
-                      [ 'arm_fpu=="vfpv3-d16"', {
-                        'defines': [
-                          'CAN_USE_VFP3_INSTRUCTIONS',
-                        ],
-                      }],
-                      [ 'arm_fpu=="vfpv3"', {
-                        'defines': [
-                          'CAN_USE_VFP3_INSTRUCTIONS',
-                          'CAN_USE_VFP32DREGS',
-                        ],
-                      }],
-                      [ 'arm_fpu=="neon"', {
-                        'defines': [
-                          'CAN_USE_VFP3_INSTRUCTIONS',
-                          'CAN_USE_VFP32DREGS',
-                          'CAN_USE_NEON',
-                        ],
-                      }],
-                    ],
-                  }],
                 ],
               }, {
                 # armcompiler=="no"
                 'conditions': [
-                  [ 'arm_version==7 or arm_version=="default"', {
-                    'defines': [
-                      'CAN_USE_ARMV7_INSTRUCTIONS=1',
-                    ],
-                    'conditions': [
-                      [ 'arm_fpu=="default"', {
-                        'defines': [
-                          'CAN_USE_VFP3_INSTRUCTIONS',
-                          'CAN_USE_VFP32DREGS',
-                          'CAN_USE_NEON',
-                        ],
-                      }],
-                      [ 'arm_fpu=="vfpv3-d16"', {
-                        'defines': [
-                          'CAN_USE_VFP3_INSTRUCTIONS',
-                        ],
-                      }],
-                      [ 'arm_fpu=="vfpv3"', {
-                        'defines': [
-                          'CAN_USE_VFP3_INSTRUCTIONS',
-                          'CAN_USE_VFP32DREGS',
-                        ],
-                      }],
-                      [ 'arm_fpu=="neon"', {
-                        'defines': [
-                          'CAN_USE_VFP3_INSTRUCTIONS',
-                          'CAN_USE_VFP32DREGS',
-                          'CAN_USE_NEON',
-                        ],
-                      }],
-                    ],
-                  }],
                   [ 'arm_float_abi=="hard"', {
                     'defines': [
                       'USE_EABI_HARDFLOAT=1',
                     ],
                   }],
                   [ 'arm_float_abi=="softfp" or arm_float_abi=="default"', {
                     'defines': [
                       'USE_EABI_HARDFLOAT=0',
                     ],
                   }],
                 ],
-                'defines': [
-                  'ARM_TEST',
-                ],
               }],
             ],
           }],  # _toolset=="target"
         ],
       }],  # v8_target_arch=="arm"
       ['v8_target_arch=="arm64"', {
         'defines': [
           'V8_TARGET_ARCH_ARM64',
         ],
       }],
@@ skipping 521 matching lines @@
                 'OptimizeReferences': '2',
                 'EnableCOMDATFolding': '2',
               },
             },
           }],  # OS=="win"
         ],  # conditions
       },  # Release
     },  # configurations
   },  # target_defaults
 }