ARM: add AArch32 support and new vcvt instructions

build/toolchain.gypi

Index: build/toolchain.gypi
diff --git a/build/toolchain.gypi b/build/toolchain.gypi
index 6b421cad5b7cc71591514bff1fbc607e5343fddb..c3b1d0abff886fabaf15390d4826c2a252177336 100644
--- a/build/toolchain.gypi
+++ b/build/toolchain.gypi
@@ -97,10 +97,13 @@
             'conditions': [
               ['armcompiler=="yes"', {
                 'conditions': [
+                  [ 'arm_version==8', {
+                    'cflags': ['-march=armv8-a',],
+                  }],
                   [ 'arm_version==7', {
                     'cflags': ['-march=armv7-a',],
                   }],
-                  [ 'arm_version==7 or arm_version=="default"', {
+                  [ 'arm_version>=7 or arm_version=="default"', {
                     'conditions': [
                       [ 'arm_fpu!="default"', {
                         'cflags': ['-mfpu=<(arm_fpu)',],
@@ -125,6 +128,15 @@
               }, {
                 # armcompiler=="no"
                 'conditions': [
+                  [ 'arm_version==8', {
+                    'defines': [
+                      'CAN_USE_ARMV8_INSTRUCTIONS=1',
+                      'CAN_USE_ARMV7_INSTRUCTIONS=1',
+                      'CAN_USE_VFP3_INSTRUCTIONS',
+                      'CAN_USE_VFP32DREGS',
+                      'CAN_USE_NEON',
+                    ],
+                  }],
                   [ 'arm_version==7 or arm_version=="default"', {
                     'defines': [
                       'CAN_USE_ARMV7_INSTRUCTIONS=1',
@@ -179,10 +191,13 @@
             'conditions': [
               ['armcompiler=="yes"', {
                 'conditions': [
+                  [ 'arm_version==8', {
+                    'cflags': ['-march=armv8-a',],
+                  }],
                   [ 'arm_version==7', {
                     'cflags': ['-march=armv7-a',],
                   }],
-                  [ 'arm_version==7 or arm_version=="default"', {
+                  [ 'arm_version>=7 or arm_version=="default"', {
                     'conditions': [
                       [ 'arm_fpu!="default"', {
                         'cflags': ['-mfpu=<(arm_fpu)',],
@@ -227,6 +242,15 @@
               }, {
                 # armcompiler=="no"
                 'conditions': [
+                  [ 'arm_version==8', {
+                    'defines': [
+                      'CAN_USE_ARMV8_INSTRUCTIONS=1',
+                      'CAN_USE_ARMV7_INSTRUCTIONS=1',
+                      'CAN_USE_VFP3_INSTRUCTIONS',
+                      'CAN_USE_VFP32DREGS',
+                      'CAN_USE_NEON',
+                    ],
+                  }],
                   [ 'arm_version==7 or arm_version=="default"', {
                     'defines': [
                       'CAN_USE_ARMV7_INSTRUCTIONS=1',