Compile SWT natives for Windows on Arm64 (WoA).

This commit mainly contains changes to the build.bat file,
to support compiling the SWT natives for the WoA platform.

On a WoA box, run the following commands to produce the
SWT natives (swt*.dll) for WoA:

  cd binaries\org.eclipse.swt.win32.win32.aarch64
  mvn clean process-resources -Dnative=win32.win32.aarch64

and the swt*.dll files for WoA will be created in the current directory.

(Similarly, to recompile the existing SWT x64 natives, run the following
commands on an x64 box:
  cd binaries\org.eclipse.swt.win32.win32.x86_64
  mvn clean process-resources -Dnative=win32.win32.x86_64
)

Cross-compiling between the x64 and Arm64 platforms, where either of
them can be host or target, is also possible, after setting up the
TARGET_ARCH environment variable with correct target architecture value,
and with the SWT_JAVA_HOME property pointing to an available JDK of
the target architecture.

For example, to cross-compile on an x64 host and produce SWT natives for
Arm64 target, run the following commands:

  set TARGET_ARCH=arm64
  cd binaries\org.eclipse.swt.win32.win32.aarch64
  mvn clean process-resources -Dnative=win32.win32.aarch64 -DSWT_JAVA_HOME=\path\to\arm64_jdk

and the swt*.dll files for WoA will be created in the current directory.
Note the above SWT_JAVA_HOME property in the command line which points
to an available Arm64 JDK of the target architecture.

Similarly, to cross-compile on an Arm64 host and produce SWT natives for
x64 target, run the following commands:

  set TARGET_ARCH=x64
  cd binaries\org.eclipse.swt.win32.win32.x86_64
  mvn clean process-resources -Dnative=win32.win32.x86_64 -DSWT_JAVA_HOME=\path\to\x64_jdk

and the swt*.dll files for x64 will be created in the current directory.

For cross-compiling between x64 and Arm64 to work, install the MSVC
compiler version 2022, with mandatory build tools for both platforms.

binaries/org.eclipse.swt.win32.win32.aarch64/META-INF/MANIFEST.MF

@@ -0,0 +1,34 @@
+Manifest-Version: 1.0
+Fragment-Host: org.eclipse.swt;bundle-version="[3.125.0,4.0.0)"
+Bundle-Name: %fragmentName
+Bundle-Vendor: %providerName
+Bundle-SymbolicName: org.eclipse.swt.win32.win32.aarch64; singleton:=true
+Bundle-Version: 3.125.0.qualifier
+Bundle-ManifestVersion: 2
+Bundle-Localization: fragment
+Export-Package: 
+ org.eclipse.swt,
+ org.eclipse.swt.accessibility,
+ org.eclipse.swt.awt,
+ org.eclipse.swt.browser,
+ org.eclipse.swt.custom,
+ org.eclipse.swt.dnd,
+ org.eclipse.swt.events,
+ org.eclipse.swt.graphics,
+ org.eclipse.swt.layout,
+ org.eclipse.swt.opengl,
+ org.eclipse.swt.printing,
+ org.eclipse.swt.program,
+ org.eclipse.swt.widgets,
+ org.eclipse.swt.internal; x-friends:="org.eclipse.ui",
+ org.eclipse.swt.internal.image; x-internal:=true,
+ org.eclipse.swt.ole.win32,
+ org.eclipse.swt.internal.gdip; x-internal:=true,
+ org.eclipse.swt.internal.ole.win32; x-internal:=true,
+ org.eclipse.swt.internal.win32; x-internal:=true,
+ org.eclipse.swt.internal.opengl.win32; x-internal:=true
+Eclipse-PlatformFilter: (& (osgi.ws=win32) (osgi.os=win32) (osgi.arch=aarch64))
+SWT-WS: win32
+SWT-OS: win32
+SWT-Arch: aarch64
+Automatic-Module-Name: org.eclipse.swt.win32.win32.aarch64

binaries/org.eclipse.swt.win32.win32.aarch64/build.properties

@@ -0,0 +1,40 @@
+###############################################################################
+# Copyright (c) 2023, 2024 Tue Ton and others.
+# All rights reserved. This program and the accompanying materials
+# are made available under the terms of the Eclipse Public License v1.0
+# which accompanies this distribution, and is available at
+# http://www.eclipse.org/legal/epl-v10.html
+#
+# Contributors:
+#     Tue Ton - initial API and implementation
+#     Hannes Wellmann - Leverage Tycho pomless
+###############################################################################
+custom = true
+bin.includes = .,*.dll,about_files/,about.html,fragment.properties
+bin.excludes = library/
+source.. = \
+	../../bundles/org.eclipse.swt/Eclipse SWT/win32,\
+	../../bundles/org.eclipse.swt/Eclipse SWT/common,\
+	../../bundles/org.eclipse.swt/Eclipse SWT PI/common,\
+	../../bundles/org.eclipse.swt/Eclipse SWT PI/win32,\
+	../../bundles/org.eclipse.swt/Eclipse SWT OLE Win32/win32,\
+	../../bundles/org.eclipse.swt/Eclipse SWT Accessibility/win32,\
+	../../bundles/org.eclipse.swt/Eclipse SWT Accessibility/common,\
+	../../bundles/org.eclipse.swt/Eclipse SWT AWT/win32,\
+	../../bundles/org.eclipse.swt/Eclipse SWT AWT/common,\
+	../../bundles/org.eclipse.swt/Eclipse SWT Drag and Drop/win32,\
+	../../bundles/org.eclipse.swt/Eclipse SWT Drag and Drop/common,\
+	../../bundles/org.eclipse.swt/Eclipse SWT Printing/win32,\
+	../../bundles/org.eclipse.swt/Eclipse SWT Printing/common,\
+	../../bundles/org.eclipse.swt/Eclipse SWT Program/win32,\
+	../../bundles/org.eclipse.swt/Eclipse SWT Program/common,\
+	../../bundles/org.eclipse.swt/Eclipse SWT Custom Widgets/common,\
+	../../bundles/org.eclipse.swt/Eclipse SWT Browser/common,\
+	../../bundles/org.eclipse.swt/Eclipse SWT Browser/win32,\
+	../../bundles/org.eclipse.swt/Eclipse SWT OpenGL/win32,\
+	../../bundles/org.eclipse.swt/Eclipse SWT OpenGL/common
+src.includes = about.html,about_files/
+
+pom.model.property.os=win32
+pom.model.property.ws=win32
+pom.model.property.arch=aarch64

bundles/org.eclipse.swt/Eclipse SWT PI/win32/library/build.bat

@@ -13,7 +13,6 @@
 @rem ***************************************************************************
 
 @rem The original build.bat source is located in /org.eclipse.swt/Eclipse SWT PI/win32/library/build.bat. It is copied during various build(s).
-@rem Typically it's not ran directly, instead it is reached by build.xml's build_libraries target found in eclipse.platform.swt\bundles\org.eclipse.swt.win32.win32.x86*
 
 @echo off
 echo
@@ -51,15 +50,44 @@ IF NOT EXIST "%MSVC_HOME%" (
 @rem Check for a usable JDK
 IF "%SWT_JAVA_HOME%"=="" CALL :ECHO "'SWT_JAVA_HOME' was not provided"
 IF NOT EXIST "%SWT_JAVA_HOME%" (
-    CALL :ECHO "WARNING: x64 Java JDK not found. Please set SWT_JAVA_HOME to the JDK directory containing the intended JDK native headers."
+    CALL :ECHO "WARNING: 64-bit Java JDK not found. Please set SWT_JAVA_HOME to the JDK directory containing the intended JDK native headers."
 )
 
-@rem -----------------------
-set PROCESSOR_ARCHITECTURE=AMD64
-IF "x.%OUTPUT_DIR%"=="x." set OUTPUT_DIR=..\..\..\org.eclipse.swt.win32.win32.x86_64
+@REM Compose host architecture string for MSVC
+IF "%PROCESSOR_ARCHITECTURE%"=="AMD64" (
+  SET HOST_ARCH=x64
+) ELSE IF "%PROCESSOR_ARCHITECTURE%"=="ARM64" (
+  SET HOST_ARCH=arm64
+) ELSE (
+  CALL :ECHO "ERROR: Unknown host architecture: %PROCESSOR_ARCHITECTURE%."
+  EXIT /B 1
+)
+
+@REM %TARGET_ARCH% may be specified by the caller for cross-compiling.
+@REM If not, build for builder machine's architecture
+IF "%TARGET_ARCH%"=="" (
+  SET TARGET_ARCH=%HOST_ARCH%
+)
+
+@REM Compose build argument for MSVC
+IF "%TARGET_ARCH%"=="%HOST_ARCH%" (
+  SET BUILD_ARCH=%TARGET_ARCH%
+) ELSE (
+  SET BUILD_ARCH=%HOST_ARCH%_%TARGET_ARCH%
+)
+
+@REM Select build's output directory (if not specified) based on target arch
+IF "%TARGET_ARCH%"=="x64" (
+  IF "x.%OUTPUT_DIR%"=="x." SET OUTPUT_DIR=..\..\..\org.eclipse.swt.win32.win32.x86_64
+) ELSE IF "%TARGET_ARCH%"=="arm64" (
+  IF "x.%OUTPUT_DIR%"=="x." SET OUTPUT_DIR=..\..\..\org.eclipse.swt.win32.win32.aarch64
+) ELSE (
+  CALL :ECHO "ERROR: Unknown target architecture: %TARGET_ARCH%."
+  EXIT /B 1
+)
 
 set CFLAGS=-DJNI64
-call "%MSVC_HOME%\VC\Auxiliary\Build\vcvarsall.bat" x64
+call "%MSVC_HOME%\VC\Auxiliary\Build\vcvarsall.bat" %BUILD_ARCH%
 
 @rem if call to vcvarsall.bat (which sets up environment) silently fails, then provide advice to user.
 WHERE cl