Remove asm.js support from HTML5 platform

Since WebGL 2.0 is required, requiring WebAssembly support as well has
little impact on compatibility.

7 files changed, 25 insertions, 148 deletions

diff --git a/misc/dist/html/default.html b/misc/dist/html/default.html
index 9fae34f97e..91193eea47 100644
--- a/misc/dist/html/default.html
+++ b/misc/dist/html/default.html
@@ -230,7 +230,6 @@ $GODOT_HEAD_INCLUDE
 		(function() {
 
 			const BASENAME = '$GODOT_BASENAME';
-			const MEMORY_SIZE = $GODOT_TOTAL_MEMORY;
 			const DEBUG_ENABLED = $GODOT_DEBUG_ENABLED;
 			const INDETERMINATE_STATUS_STEP_MS = 100;
 
@@ -247,7 +246,6 @@ $GODOT_HEAD_INCLUDE
 
 			setStatusMode('indeterminate');
 			game.setCanvas(canvas);
-			game.setAsmjsMemorySize(MEMORY_SIZE);
 
 			function setStatusMode(mode) {
 
diff --git a/platform/javascript/SCsub b/platform/javascript/SCsub
index e3015d87b9..8d505a5829 100644
--- a/platform/javascript/SCsub
+++ b/platform/javascript/SCsub
@@ -21,37 +21,21 @@ for x in javascript_files:
 
 env.Append(LINKFLAGS=["-s", "EXPORTED_FUNCTIONS=\"['_main','_main_after_fs_sync','_send_notification']\""])
 
-# output file name without file extension
-basename = "godot" + env["PROGSUFFIX"]
 target_dir = env.Dir("#bin")
-
-zip_dir = target_dir.Dir('.javascript_zip')
-zip_files = env.InstallAs(zip_dir.File('godot.html'), '#misc/dist/html/default.html')
-
-implicit_targets = []
-if env['wasm']:
-    wasm = target_dir.File(basename + '.wasm')
-    implicit_targets.append(wasm)
-    zip_files.append(InstallAs(zip_dir.File('godot.wasm'), wasm))
-    prejs = env.File('pre_wasm.js')
-else:
-    asmjs_files = [target_dir.File(basename + '.asm.js'), target_dir.File(basename + '.js.mem')]
-    implicit_targets.extend(asmjs_files)
-    zip_files.append(InstallAs([zip_dir.File('godot.asm.js'), zip_dir.File('godot.mem')], asmjs_files))
-    prejs = env.File('pre_asmjs.js')
-
-js = env.Program(['#bin/godot'] + implicit_targets, javascript_objects, PROGSUFFIX=env['PROGSUFFIX'] + '.js')[0];
-zip_files.append(InstallAs(zip_dir.File('godot.js'), js))
+build = env.Program(['#bin/godot', target_dir.File('godot' + env['PROGSUFFIX'] + '.wasm')], javascript_objects, PROGSUFFIX=env['PROGSUFFIX'] + '.js');
 
 js_libraries = []
 js_libraries.append(env.File('http_request.js'))
 for lib in js_libraries:
     env.Append(LINKFLAGS=['--js-library', lib.path])
-env.Depends(js, js_libraries)
+env.Depends(build, js_libraries)
 
+prejs = env.File('pre.js')
 postjs = env.File('engine.js')
-env.Depends(js, [prejs, postjs])
 env.Append(LINKFLAGS=['--pre-js', prejs.path])
 env.Append(LINKFLAGS=['--post-js', postjs.path])
+env.Depends(build, [prejs, postjs])
 
+zip_dir = target_dir.Dir('.javascript_zip')
+zip_files = env.InstallAs([zip_dir.File('godot.js'), zip_dir.File('godot.wasm'), zip_dir.File('godot.html')], build + ['#misc/dist/html/default.html'])
 Zip('#bin/godot', zip_files, ZIPSUFFIX=env['PROGSUFFIX'] + env['ZIPSUFFIX'], ZIPROOT=zip_dir, ZIPCOMSTR="Archving $SOURCES as $TARGET")
diff --git a/platform/javascript/detect.py b/platform/javascript/detect.py
index a2988d9c60..ba0b63a375 100644
--- a/platform/javascript/detect.py
+++ b/platform/javascript/detect.py
@@ -19,7 +19,6 @@ def can_build():
 def get_opts():
     from SCons.Variables import BoolVariable
     return [
-        BoolVariable('wasm', 'Compile to WebAssembly', False),
         BoolVariable('javascript_eval', 'Enable JavaScript eval interface', True),
     ]
 
@@ -106,17 +105,11 @@ def configure(env):
     env.Append(LINKFLAGS=['-s', 'EXTRA_EXPORTED_RUNTIME_METHODS="[\'FS\']"'])
     env.Append(LINKFLAGS=['-s', 'USE_WEBGL2=1'])
 
-    if env['wasm']:
-        env.Append(LINKFLAGS=['-s', 'BINARYEN=1'])
-        # In contrast to asm.js, enabling memory growth on WebAssembly has no
-        # major performance impact, and causes only a negligible increase in
-        # memory size.
-        env.Append(LINKFLAGS=['-s', 'ALLOW_MEMORY_GROWTH=1'])
-        env.extra_suffix = '.webassembly' + env.extra_suffix
-    else:
-        env.Append(LINKFLAGS=['-s', 'ASM_JS=1'])
-        env.Append(LINKFLAGS=['--separate-asm'])
-        env.Append(LINKFLAGS=['--memory-init-file', '1'])
+    env.Append(LINKFLAGS=['-s', 'BINARYEN=1'])
+    # In contrast to asm.js, enabling memory growth on WebAssembly has no
+    # major performance impact, and causes only a negligible increase in
+    # memory size.
+    env.Append(LINKFLAGS=['-s', 'ALLOW_MEMORY_GROWTH=1'])
 
     # TODO: Move that to opus module's config
     if 'module_opus_enabled' in env and env['module_opus_enabled']:
diff --git a/platform/javascript/engine.js b/platform/javascript/engine.js
index 99d1c20bbd..f3a7c49a95 100644
--- a/platform/javascript/engine.js
+++ b/platform/javascript/engine.js
@@ -5,7 +5,6 @@
 (function() {
 	var engine = Engine;
 
-	var USING_WASM = engine.USING_WASM;
 	var DOWNLOAD_ATTEMPTS_MAX = 4;
 
 	var basePath = null;
@@ -34,7 +33,6 @@
 
 		var gameInitPromise = null;
 		var unloadAfterInit = true;
-		var memorySize = 268435456;
 
 		var progressFunc = null;
 		var pckProgressTracker = {};
@@ -91,10 +89,6 @@
 					});
 					return {};
 				};
-			} else if (initializer.asm && initializer.mem) {
-				rtenvOpts.asm = initializer.asm;
-				rtenvOpts.memoryInitializerRequest = initializer.mem;
-				rtenvOpts.TOTAL_MEMORY = memorySize;
 			} else {
 				throw new Error("Invalid initializer");
 			}
@@ -190,10 +184,6 @@
 			canvas = elem;
 		};
 
-		this.setAsmjsMemorySize = function(size) {
-			memorySize = size;
-		};
-
 		this.setUnloadAfterInit = function(enabled) {
 
 			if (enabled && !unloadAfterInit && gameInitPromise) {
@@ -236,22 +226,12 @@
 
 		if (newBasePath !== undefined) basePath = getBasePath(newBasePath);
 		if (engineLoadPromise === null) {
-			if (USING_WASM) {
-				if (typeof WebAssembly !== 'object')
-					return Promise.reject(new Error("Browser doesn't support WebAssembly"));
-				// TODO cache/retrieve module to/from idb
-				engineLoadPromise = loadPromise(basePath + '.wasm').then(function(xhr) {
-					return xhr.response;
-				});
-			} else {
-				var asmjsPromise = loadPromise(basePath + '.asm.js').then(function(xhr) {
-					return asmjsModulePromise(xhr.response);
-				});
-				var memPromise = loadPromise(basePath + '.mem');
-				engineLoadPromise = Promise.all([asmjsPromise, memPromise]).then(function(values) {
-					return { asm: values[0], mem: values[1] };
-				});
-			}
+			if (typeof WebAssembly !== 'object')
+				return Promise.reject(new Error("Browser doesn't support WebAssembly"));
+			// TODO cache/retrieve module to/from idb
+			engineLoadPromise = loadPromise(basePath + '.wasm').then(function(xhr) {
+				return xhr.response;
+			});
 			engineLoadPromise = engineLoadPromise.catch(function(err) {
 				engineLoadPromise = null;
 				throw err;
@@ -260,33 +240,6 @@
 		return engineLoadPromise;
 	};
 
-	function asmjsModulePromise(module) {
-		var elem = document.createElement('script');
-		var script = new Blob([
-			'Engine.asm = (function() { var Module = {};',
-			module,
-			'return Module.asm; })();'
-		]);
-		var url = URL.createObjectURL(script);
-		elem.src = url;
-		return new Promise(function(resolve, reject) {
-			elem.addEventListener('load', function() {
-				URL.revokeObjectURL(url);
-				var asm = Engine.asm;
-				Engine.asm = undefined;
-				setTimeout(function() {
-					// delay to reclaim compilation memory
-					resolve(asm);
-				}, 1);
-			});
-			elem.addEventListener('error', function() {
-				URL.revokeObjectURL(url);
-				reject("asm.js faiilure");
-			});
-			document.body.appendChild(elem);
-		});
-	}
-
 	Engine.unloadEngine = function() {
 		engineLoadPromise = null;
 	};
diff --git a/platform/javascript/export/export.cpp b/platform/javascript/export/export.cpp
index 4a97bf4c32..d0d4b17874 100644
--- a/platform/javascript/export/export.cpp
+++ b/platform/javascript/export/export.cpp
@@ -35,8 +35,6 @@
 
 #define EXPORT_TEMPLATE_WEBASSEMBLY_RELEASE "webassembly_release.zip"
 #define EXPORT_TEMPLATE_WEBASSEMBLY_DEBUG "webassembly_debug.zip"
-#define EXPORT_TEMPLATE_ASMJS_RELEASE "javascript_release.zip"
-#define EXPORT_TEMPLATE_ASMJS_DEBUG "javascript_debug.zip"
 
 class EditorExportPlatformJavaScript : public EditorExportPlatform {
 
@@ -47,18 +45,11 @@ class EditorExportPlatformJavaScript : public EditorExportPlatform {
 	bool runnable_when_last_polled;
 
 	void _fix_html(Vector<uint8_t> &p_html, const Ref<EditorExportPreset> &p_preset, const String &p_name, bool p_debug);
-	void _fix_fsloader_js(Vector<uint8_t> &p_js, const String &p_pack_name, uint64_t p_pack_size);
 
 public:
-	enum Target {
-		TARGET_WEBASSEMBLY,
-		TARGET_ASMJS
-	};
-
 	virtual void get_preset_features(const Ref<EditorExportPreset> &p_preset, List<String> *r_features);
 
 	virtual void get_export_options(List<ExportOption> *r_options);
-	virtual bool get_option_visibility(const String &p_option, const Map<StringName, Variant> &p_options) const;
 
 	virtual String get_name() const;
 	virtual String get_os_name() const;
@@ -90,17 +81,9 @@ void EditorExportPlatformJavaScript::_fix_html(Vector<uint8_t> &p_html, const Re
 	String str_export;
 	Vector<String> lines = str_template.split("\n");
 
-	int memory_mb;
-	if (p_preset->get("options/target").operator int() != TARGET_ASMJS)
-		// WebAssembly allows memory growth, so start with a reasonable default
-		memory_mb = 1 << 4;
-	else
-		memory_mb = 1 << (p_preset->get("options/memory_size").operator int() + 5);
-
 	for (int i = 0; i < lines.size(); i++) {
 
 		String current_line = lines[i];
-		current_line = current_line.replace("$GODOT_TOTAL_MEMORY", itos(memory_mb * 1024 * 1024));
 		current_line = current_line.replace("$GODOT_BASENAME", p_name);
 		current_line = current_line.replace("$GODOT_HEAD_INCLUDE", p_preset->get("html/head_include"));
 		current_line = current_line.replace("$GODOT_DEBUG_ENABLED", p_debug ? "true" : "false");
@@ -129,8 +112,6 @@ void EditorExportPlatformJavaScript::get_preset_features(const Ref<EditorExportP
 
 void EditorExportPlatformJavaScript::get_export_options(List<ExportOption> *r_options) {
 
-	r_options->push_back(ExportOption(PropertyInfo(Variant::INT, "options/target", PROPERTY_HINT_ENUM, "WebAssembly,asm.js"), TARGET_WEBASSEMBLY));
-	r_options->push_back(ExportOption(PropertyInfo(Variant::INT, "options/memory_size", PROPERTY_HINT_ENUM, "32 MB,64 MB,128 MB,256 MB,512 MB,1 GB"), 3));
 	r_options->push_back(ExportOption(PropertyInfo(Variant::BOOL, "texture_format/s3tc"), false));
 	r_options->push_back(ExportOption(PropertyInfo(Variant::BOOL, "texture_format/etc"), true));
 	r_options->push_back(ExportOption(PropertyInfo(Variant::BOOL, "texture_format/etc2"), false));
@@ -139,14 +120,6 @@ void EditorExportPlatformJavaScript::get_export_options(List<ExportOption> *r_op
 	r_options->push_back(ExportOption(PropertyInfo(Variant::STRING, "custom_template/debug", PROPERTY_HINT_GLOBAL_FILE, "zip"), ""));
 }
 
-bool EditorExportPlatformJavaScript::get_option_visibility(const String &p_option, const Map<StringName, Variant> &p_options) const {
-
-	if (p_option == "options/memory_size") {
-		return p_options["options/target"].operator int() == TARGET_ASMJS;
-	}
-	return true;
-}
-
 String EditorExportPlatformJavaScript::get_name() const {
 
 	return "HTML5";
@@ -166,17 +139,10 @@ bool EditorExportPlatformJavaScript::can_export(const Ref<EditorExportPreset> &p
 
 	r_missing_templates = false;
 
-	if (p_preset->get("options/target").operator int() == TARGET_WEBASSEMBLY) {
-		if (find_export_template(EXPORT_TEMPLATE_WEBASSEMBLY_RELEASE) == String())
-			r_missing_templates = true;
-		else if (find_export_template(EXPORT_TEMPLATE_WEBASSEMBLY_DEBUG) == String())
-			r_missing_templates = true;
-	} else {
-		if (find_export_template(EXPORT_TEMPLATE_ASMJS_RELEASE) == String())
-			r_missing_templates = true;
-		else if (find_export_template(EXPORT_TEMPLATE_ASMJS_DEBUG) == String())
-			r_missing_templates = true;
-	}
+	if (find_export_template(EXPORT_TEMPLATE_WEBASSEMBLY_RELEASE) == String())
+		r_missing_templates = true;
+	else if (find_export_template(EXPORT_TEMPLATE_WEBASSEMBLY_DEBUG) == String())
+		r_missing_templates = true;
 
 	return !r_missing_templates;
 }
@@ -197,17 +163,10 @@ Error EditorExportPlatformJavaScript::export_project(const Ref<EditorExportPrese
 
 	if (template_path == String()) {
 
-		if (p_preset->get("options/target").operator int() == TARGET_WEBASSEMBLY) {
-			if (p_debug)
-				template_path = find_export_template(EXPORT_TEMPLATE_WEBASSEMBLY_DEBUG);
-			else
-				template_path = find_export_template(EXPORT_TEMPLATE_WEBASSEMBLY_RELEASE);
-		} else {
-			if (p_debug)
-				template_path = find_export_template(EXPORT_TEMPLATE_ASMJS_DEBUG);
-			else
-				template_path = find_export_template(EXPORT_TEMPLATE_ASMJS_RELEASE);
-		}
+		if (p_debug)
+			template_path = find_export_template(EXPORT_TEMPLATE_WEBASSEMBLY_DEBUG);
+		else
+			template_path = find_export_template(EXPORT_TEMPLATE_WEBASSEMBLY_RELEASE);
 	}
 
 	if (template_path != String() && !FileAccess::exists(template_path)) {
@@ -270,12 +229,6 @@ Error EditorExportPlatformJavaScript::export_project(const Ref<EditorExportPrese
 		} else if (file == "godot.wasm") {
 
 			file = p_path.get_file().get_basename() + ".wasm";
-		} else if (file == "godot.asm.js") {
-
-			file = p_path.get_file().get_basename() + ".asm.js";
-		} else if (file == "godot.mem") {
-
-			file = p_path.get_file().get_basename() + ".mem";
 		}
 
 		String dst = p_path.get_base_dir().plus_file(file);
diff --git a/platform/javascript/pre_wasm.js b/platform/javascript/pre.js
index be4383c8c9..311aa44fda 100644
--- a/platform/javascript/pre_wasm.js
+++ b/platform/javascript/pre.js
@@ -1,3 +1,2 @@
 var Engine = {
-	USING_WASM: true,
 	RuntimeEnvironment: function(Module) {
diff --git a/platform/javascript/pre_asmjs.js b/platform/javascript/pre_asmjs.js
deleted file mode 100644
index 3c497721b6..0000000000
--- a/platform/javascript/pre_asmjs.js
+++ /dev/null
@@ -1,3 +0,0 @@
-var Engine = {
-	USING_WASM: false,
-	RuntimeEnvironment: function(Module) {