Android: Add support for x86_64 architecture

Like arm64v8, this is only supported by API 21 and later,
so we enforce 21 as min API for x86_64.

Part of #25030.

modules/webm/libvpx/SCsub

@@ -272,9 +272,9 @@ else:
     import platform
     is_x11_or_server_arm = ((env["platform"] == 'x11' or env["platform"] == 'server') and (platform.machine().startswith('arm') or platform.machine().startswith('aarch')))
     is_ios_x86 = (env["platform"] == 'iphone' and ("arch" in env and env["arch"].startswith('x86')))
-    is_android_x86 = (env["platform"] == 'android' and env["android_arch"] == 'x86')
+    is_android_x86 = (env["platform"] == 'android' and env["android_arch"].startswith('x86'))
     if is_android_x86:
-        cpu_bits = '32'
+        cpu_bits = '32' if env["android_arch"] == 'x86' else '64'
     webm_cpu_x86 = not is_x11_or_server_arm and (cpu_bits == '32' or cpu_bits == '64') and (env["platform"] == 'windows' or env["platform"] == 'x11' or env["platform"] == 'osx' or env["platform"] == 'haiku' or is_android_x86 or is_ios_x86)
     webm_cpu_arm = is_x11_or_server_arm or (not is_ios_x86 and env["platform"] == 'iphone') or (not is_android_x86 and env["platform"] == 'android')
 

platform/android/SCsub

@@ -152,6 +152,8 @@ elif env['android_arch'] == 'arm64v8':
     lib_arch_dir = 'arm64-v8a'
 elif env['android_arch'] == 'x86':
     lib_arch_dir = 'x86'
+elif env['android_arch'] == 'x86_64':
+    lib_arch_dir = 'x86_64'
 else:
     print('WARN: Architecture not suitable for embedding into APK; keeping .so at \\bin')
 

platform/android/detect.py

@@ -27,7 +27,7 @@ def get_opts():
     return [
         ('ANDROID_NDK_ROOT', 'Path to the Android NDK', os.environ.get("ANDROID_NDK_ROOT", 0)),
         ('ndk_platform', 'Target platform (android-<api>, e.g. "android-18")', "android-18"),
-        EnumVariable('android_arch', 'Target architecture', "armv7", ('armv7', 'armv6', 'arm64v8', 'x86')),
+        EnumVariable('android_arch', 'Target architecture', "armv7", ('armv7', 'armv6', 'arm64v8', 'x86', 'x86_64')),
         BoolVariable('android_neon', 'Enable NEON support (armv7 only)', True),
         BoolVariable('android_stl', 'Enable Android STL support (for modules)', True)
     ]
@@ -94,7 +94,7 @@ def configure(env):
 
     ## Architecture
 
-    if env['android_arch'] not in ['armv7', 'armv6', 'arm64v8', 'x86']:
+    if env['android_arch'] not in ['armv7', 'armv6', 'arm64v8', 'x86', 'x86_64']:
         env['android_arch'] = 'armv7'
 
     neon_text = ""
@@ -110,6 +110,16 @@ def configure(env):
         abi_subpath = "i686-linux-android"
         arch_subpath = "x86"
         env["x86_libtheora_opt_gcc"] = True
+    if env['android_arch'] == 'x86_64':
+        if get_platform(env["ndk_platform"]) < 21:
+            print("WARNING: android_arch=x86_64 is not supported by ndk_platform lower than android-21; setting ndk_platform=android-21")
+            env["ndk_platform"] = "android-21"
+        env['ARCH'] = 'arch-x86_64'
+        env.extra_suffix = ".x86_64" + env.extra_suffix
+        target_subpath = "x86_64-4.9"
+        abi_subpath = "x86_64-linux-android"
+        arch_subpath = "x86_64"
+        env["x86_libtheora_opt_gcc"] = True
     elif env['android_arch'] == 'armv6':
         env['ARCH'] = 'arch-arm'
         env.extra_suffix = ".armv6" + env.extra_suffix
@@ -233,6 +243,9 @@ def configure(env):
         # The NDK adds this if targeting API < 21, so we can drop it when Godot targets it at least
         env.Append(CPPFLAGS=['-mstackrealign'])
 
+    elif env['android_arch'] == 'x86_64':
+        target_opts = ['-target', 'x86_64-none-linux-android']
+
     elif env["android_arch"] == "armv6":
         target_opts = ['-target', 'armv6-none-linux-androideabi']
         env.Append(CPPFLAGS='-D__ARM_ARCH_6__ -march=armv6 -mfpu=vfp -mfloat-abi=softfp'.split())

platform/android/export/export.cpp

@@ -552,14 +552,13 @@ class EditorExportAndroid : public EditorExportPlatform {
 
 	static Vector<String> get_abis() {
 		Vector<String> abis;
-		// We can still build armv7 in theory, but it doesn't make much
+		// We can still build armv6 in theory, but it doesn't make much
 		// sense for games, so disabling for now.
 		//abis.push_back("armeabi");
 		abis.push_back("armeabi-v7a");
 		abis.push_back("arm64-v8a");
 		abis.push_back("x86");
-		// Don't expose x86_64 for now, we don't support it in detect.py
-		//abis.push_back("x86_64");
+		abis.push_back("x86_64");
 		return abis;
 	}