[Windows] Add SSE4.2 support runtime check.

platform/windows/SCsub

@@ -37,6 +37,20 @@ common_win_wrap = [
     "console_wrapper_windows.cpp",
 ]
 
+env_wrap = env.Clone()
+
+if env["arch"] == "x86_64":
+    env_cpp_check = env.Clone()
+    env_cpp_check.add_source_files(sources, ["cpu_feature_validation.c"])
+    if env.msvc:
+        if "/d2archSSE42" in env_cpp_check["CCFLAGS"]:
+            env_cpp_check["CCFLAGS"].remove("/d2archSSE42")
+        env.Append(LINKFLAGS=["/ENTRY:ShimMainCRTStartup"])
+    else:
+        if "-msse4.2" in env_cpp_check["CCFLAGS"]:
+            env_cpp_check["CCFLAGS"].remove("-msse4.2")
+        env.Append(LINKFLAGS=["-Wl,--entry=ShimMainCRTStartup"])
+
 
 def arrange_program_clean(prog):
     """
@@ -74,7 +88,6 @@ if env.msvc:
 
 # Build console wrapper app.
 if env["windows_subsystem"] == "gui":
-    env_wrap = env.Clone()
     res_wrap_file = "godot_res_wrap.rc"
     res_wrap_target = "godot_res_wrap" + env["OBJSUFFIX"]
     res_wrap_obj = env_wrap.RES(res_wrap_target, res_wrap_file)

platform/windows/cpu_feature_validation.c

@@ -0,0 +1,50 @@
+/**************************************************************************/
+/*  cpu_feature_validation.c                                              */
+/**************************************************************************/
+/*                         This file is part of:                          */
+/*                             GODOT ENGINE                               */
+/*                        https://godotengine.org                         */
+/**************************************************************************/
+/* Copyright (c) 2014-present Godot Engine contributors (see AUTHORS.md). */
+/* Copyright (c) 2007-2014 Juan Linietsky, Ariel Manzur.                  */
+/*                                                                        */
+/* Permission is hereby granted, free of charge, to any person obtaining  */
+/* a copy of this software and associated documentation files (the        */
+/* "Software"), to deal in the Software without restriction, including    */
+/* without limitation the rights to use, copy, modify, merge, publish,    */
+/* distribute, sublicense, and/or sell copies of the Software, and to     */
+/* permit persons to whom the Software is furnished to do so, subject to  */
+/* the following conditions:                                              */
+/*                                                                        */
+/* The above copyright notice and this permission notice shall be         */
+/* included in all copies or substantial portions of the Software.        */
+/*                                                                        */
+/* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,        */
+/* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF     */
+/* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. */
+/* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY   */
+/* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,   */
+/* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE      */
+/* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.                 */
+/**************************************************************************/
+
+#include <windows.h>
+
+#ifdef WINDOWS_SUBSYSTEM_CONSOLE
+extern int WINAPI mainCRTStartup();
+#else
+extern int WINAPI WinMainCRTStartup();
+#endif
+
+extern int WINAPI ShimMainCRTStartup() {
+	if (IsProcessorFeaturePresent(PF_SSE4_2_INSTRUCTIONS_AVAILABLE)) {
+#ifdef WINDOWS_SUBSYSTEM_CONSOLE
+		return mainCRTStartup();
+#else
+		return WinMainCRTStartup();
+#endif
+	} else {
+		MessageBoxW(NULL, L"A CPU with SSE4.2 instruction set support is required.", L"Godot Engine", MB_OK | MB_ICONEXCLAMATION | MB_TASKMODAL);
+		return -1;
+	}
+}