Getting Started on Windows

There are multiple ways to develop on Windows, and compared to other environments, batteries are often not included. This document outlines the setup that is known to work for the IREE developers. Other setups almost certainly work as well.

Pre-requisites

Enable Developer Mode

We use symlinks in the build, and this requires developer mode to be enabled:

  • Open Settings
  • Search for “Developer Settings”
  • Select the radio button “Developer mode” and accept all prompts

Install Build Tools For Visual Studio

At the time of writing, this can be found by going to this page and finding the Download link for “Build Tools for Visual Studio 2019”.

Minimally select to install “C++ Build Tools”.

Install the Scoop Package Manager

The Scoop page is here. Follow the instructions at the bottom.

IMPORTANT: When launching PowerShell, make sure to not select any option that ends in “(x86)” as this will install the 32bit version, and all of the software that Scoop installs will be 32bit. While 32bit builds of the project may be possible, we only (presently) support 64bit. Also, not all packages are available in 32bit.

Install Scoop Packages

Home Directory

Optional: Set the msys2 home directory to your Windows home directory. By default, the msys2 HOME will be nested inside the installation directory, which is managed by scoop and somewhat ephemeral.

  • Open the Windows environment dialog (This PC -> Properties -> Advanced Settings -> Environment Variables...)
  • Add a new User variable: HOME = C:\Users\%USERNAME% (replacing with the actual location of your Windows home directory).
  • Ok out of all dialogs
  • Restart PowerShell
  • Verify that it took effect (Get-ChildItem Env:HOME)

While here, also consider adding GIT_SSH=C:/Users/%USERNAME%/scoop/shims/ssh which will help git find the right SSH and keys (you probably want this as a global to Windows vs just in your shell, which is why it is recommended here).

Scoop Package Setup

In PowerShell, run the following:

scoop install git nano vim
scoop bucket add extras
scoop bucket add versions
scoop install msys2
scoop install curl cmake openssh python36 llvm bazel
# Optional
scoop install vscode

TODO: Upgrade to head python.

Setup MSYS2

Then run msys2 for the first time for subsequent setup by doing one of:

  • Launch MSYS2 from the start menu
  • From a regular PowerShell terminal (not ISE, which hangs), run msys2
  • Note that full interop between native and msys2 programs requires a “native” Windows shell. “PowerShell” qualifies. “PowerShell ISE” and the way that the “MSYS2” system shortcut launch do not. You can tell if things are working by launching MSYS2 and running python (which, for us is a native windows application).
  • Reportedly, cmder is a good possibility.

You can also customize you shell, etc. From now on, when we refer to the shell, we mean “launch msys2”.

# In MSYS2 shell
pacman -S patch
# Customize the path to your home directory if required.
echo 'export PATH=/c/Users/$USERNAME/scoop/shims:$PATH' >> ~/.bash_profile

You are also going to want a few other environment variables. You are welcome to configure these however you choose. Adding them to ~/.bash_profile would look like this:

# Tells Bazel to use clang-cl instead of VS cl.
export USE_CLANG_CL=1
# Tells Bazel where the LLVM installation is.
export BAZEL_LLVM=C:/Users/$USERNAME/scoop/apps/llvm/current
# This should be automatic, but worth checking.
export BAZEL_SH=C:/Users/$USERNAME/scoop/apps/msys2/current/usr/bin/bash.exe

Optional: Configure Git

Git SSH

  • Make sure that the environment variable is set: GIT_SSH=C:/Users/%USERNAME%/scoop/shims/ssh
  • Generate SSH Key: ssh-keygen -t rsa -b 4096 -C "EMAIL@email.com"
  • Add ~/.ssh.id_rsa.pub key to GitHub
  • Try a test connection ssh git@github.com

Other git config options

# Disable stupid^H^H^H^H^H^H Windows line ending translation
git config --global core.autocrlf false
# Configure name and email before commiting anything
git config --global user.name "MY NAME"
git config --global user.email "MY EMAIL"

Clone and Build

This assumes that we are cloning into C:\src\ireepub. Update accordingly for your use.

Clone

Note that if you will be cloning frequently, it can be sped up significantly by creating a reference repo and setting IREE_CLONE_ARGS="--reference=/path/to/reference/repo". See build_tools/scripts/populate_reference_repo.sh for further details.

IREE_CLONE_ARGS=""
mkdir -p /c/src/ireepub
cd /c/src/ireepub
git clone $IREE_CLONE_ARGS https://github.com/google/iree.git iree
cd iree
git submodule init
git submodule update $IREE_CLONE_ARGS --recursive

Build

# TODO: Add more things as they come online.
# Unit tests.
bazel test --config=windows //iree/compiler/...

# Sample computation on the interpreter.
bazel run --config=windows iree/tools/iree-run-mlir -- \
    $(pwd)/iree/samples/hal/simple_compute_test.mlir \
    --input_values="4xf32=1.0 2.0 3.0 4.0\n4xf32=2.0 4.0 6.0 8.0" \
    --iree_logtostderr --target_backends=interpreter-bytecode

# Sample computation via vulkan/spirv.
bazel run --config=windows iree/tools/iree-run-mlir -- \
    $(pwd)/iree/samples/hal/simple_compute_test.mlir \
    --input_values="4xf32=1.0 2.0 3.0 4.0\n4xf32=2.0 4.0 6.0 8.0" \
    --iree_logtostderr --target_backends=vulkan

Troubleshooting

Bazel and Visual Studio Versions

In general, the software has only been build with Visual Studio 2019 Build Tools and Clang-CL 9.x. Previous versions are known to have incompatibilities in their standard libraries. If you have multiple versions of Visual Studio (and/or Build Tools) installed, Bazel may auto-detect the wrong one. You can see this by adding a -s argument to you build command and looking for a “SET INCLUDE=” line in the log output (to see where it is pointing).

You can hard-code the version that Bazel selects by setting: BAZEL_VS=C:\Program Files (x86)\Microsoft Visual Studio\2019\BuildTools.

If updating, you will need to bazel clean and bazel shutdown for changes to take effect.

See this page for more options.

If setting up a new machine, it is best to just make sure there is one version.