Add build script for Windows on ARM64

tools/build_steps_win_arm64.bat

@@ -0,0 +1,132 @@
+:: Build script for scipy_openblas wheel on Windows on ARM64
+
+:: Usage: build_steps_win_arm64.bat [build_bits]
+:: e.g build_steps_win_arm64.bat 64
+
+:: BUILD_BITS  (default binary architecture, 32 or 64, unspec -> 64).
+:: Expects these binaries on the PATH:
+:: clang-cl, flang-new, cmake, perl
+
+@echo off
+setlocal enabledelayedexpansion
+
+if "%1"=="" (
+    set BUILD_BIT=64
+) else (
+    set BUILD_BIT=%1
+)
+echo Building for %BUILD_BIT%-bit configuration...
+
+:: Define destination directory
+move "..\local\scipy_openblas64" "..\local\scipy_openblas32"
+set "DEST_DIR=%CD%\..\local\scipy_openblas32"
+cd ..
+
+:: Check if 'openblas' folder exists and is empty
+if exist "openblas" (
+    dir /b "openblas" | findstr . >nul
+    if errorlevel 1 (
+        echo OpenBLAS folder exists but is empty. Deleting and recloning...
+        rmdir /s /q "openblas"
+    )
+)
+
+:: Clone OpenBLAS if not present
+if not exist "openblas" (
+    echo Cloning OpenBLAS repository with submodules...
+    git clone --recursive https://github.com/OpenMathLib/OpenBLAS.git OpenBLAS
+    if errorlevel 1 exit /b 1
+)
+
+:: Enter OpenBLAS directory and checkout develop branch
+cd openblas
+git checkout develop
+
+echo Checked out to the latest branch of OpenBLAS.
+
+:: Create build directory and navigate to it
+if not exist build mkdir build
+cd build
+
+echo Setting up ARM64 Developer Command Prompt and running CMake...
+
+:: Initialize VS ARM64 environment
+for /f "usebackq tokens=*" %%i in (`"C:\Program Files (x86)\Microsoft Visual Studio\Installer\vswhere.exe" -latest -property installationPath`) do call "%%i\VC\Auxiliary\Build\vcvarsall.bat" arm64
+
+:: Run CMake and Ninja build
+cmake .. -G Ninja -DCMAKE_BUILD_TYPE=Release -DTARGET=ARMV8 -DBUILD_SHARED_LIBS=ON -DARCH=arm64 ^
+-DBINARY=%BUILD_BIT% -DCMAKE_SYSTEM_PROCESSOR=ARM64 -DCMAKE_C_COMPILER=clang-cl ^
+-DCMAKE_Fortran_COMPILER=flang-new -DSYMBOLPREFIX="scipy_" -DLIBNAMEPREFIX="scipy_"
+if errorlevel 1 exit /b 1
+
+ninja
+if errorlevel 1 exit /b 1
+
+echo Build complete. Returning to Batch.
+
+:: Rewrite the name of the project to scipy-openblas32
+echo Rewrite to scipy_openblas32
+cd ../..
+powershell -Command "(Get-Content 'pyproject.toml') -replace 'openblas64', 'openblas32' | Set-Content 'pyproject.toml'"
+powershell -Command "(Get-Content 'local\scipy_openblas32\__main__.py') -replace 'openblas64', 'openblas32' | Out-File 'local\scipy_openblas32\__main__.py' -Encoding utf8"
+powershell -Command "(Get-Content 'local\scipy_openblas32\__init__.py') -replace 'openblas64', 'openblas32' | Out-File 'local\scipy_openblas32\__init__.py' -Encoding utf8"
+powershell -Command "(Get-Content 'local\scipy_openblas32\__init__.py') -replace 'openblas_get_config64_', 'openblas_get_config' | Out-File 'local\scipy_openblas32\__init__.py' -Encoding utf8"
+powershell -Command "(Get-Content 'local\scipy_openblas32\__init__.py') -replace 'cflags =.*', 'cflags = \"-DBLAS_SYMBOL_PREFIX=scipy_\"' | Out-File 'local\scipy_openblas32\__init__.py' -Encoding utf8"
+
+:: Prepare destination directory
+cd OpenBLAS/build
+echo Preparing destination directory at %DEST_DIR%...
+if not exist "%DEST_DIR%\lib\cmake\openblas" mkdir "%DEST_DIR%\lib\cmake\openblas"
+if not exist "%DEST_DIR%\include" mkdir "%DEST_DIR%\include"
+
+:: Move library files
+echo Moving library files...
+if exist lib\release (
+    move /Y lib\release\*.dll "%DEST_DIR%\lib\"
+    if errorlevel 1 exit /b 1
+    move /Y lib\release\*.dll.a "%DEST_DIR%\lib\scipy_openblas.lib"
+    if errorlevel 1 exit /b 1
+) else (
+    echo Error: lib/release directory not found!
+    exit /b 1
+)
+
+:: Copy CMake configuration files
+echo Copying CMake configuration files...
+if exist openblasconfig.cmake copy /Y openblasconfig.cmake "%DEST_DIR%\lib\cmake\openblas\"
+if exist openblasconfigversion.cmake copy /Y openblasconfigversion.cmake "%DEST_DIR%\lib\cmake\openblas\"
+
+:: Copy header files
+echo Copying generated header files...
+if exist generated xcopy /E /Y generated "%DEST_DIR%\include\"
+if exist lapacke_mangling copy /Y lapacke_mangling "%DEST_DIR%\include\"
+if exist openblas_config.h copy /Y openblas_config.h "%DEST_DIR%\include\"
+
+
+:: Copy LAPACKE header files
+echo Copying LAPACKE header files...
+xcopy /Y "..\lapack-netlib\lapacke\include\*.h" "%DEST_DIR%\include\"
+if errorlevel 1 exit /b 1
+
+:: Move back to the root directory
+cd ../..
+
+:: Build the Wheel & Install It
+echo Running 'python -m build' to build the wheel...
+python -m build
+if errorlevel 1 exit /b 1
+
+:: Locate the built wheel
+for /f %%f in ('dir /b dist\scipy_openblas*.whl 2^>nul') do set WHEEL_FILE=dist\%%f
+
+if not defined WHEEL_FILE (
+    echo Error: No wheel file found in dist folder.
+    exit /b 1
+)
+
+echo Installing wheel: %WHEEL_FILE%
+pip install "%WHEEL_FILE%"
+if errorlevel 1 exit /b 1
+
+echo Done.
+exit /b 0