Introduce standalone SkalaXC with ABI-isolated CPU, CUDA, MPI, and language bindings

.github/actionlint.yaml

@@ -0,0 +1,10 @@
+self-hosted-runner:
+  labels:
+    - microsoft-skala-cpu-pool
+    - microsoft-skala-gpu-pool
+    - microsoft-skala-small-gpu-pool
+
+paths:
+  .github/workflows/**/*.{yml,yaml}:
+    ignore:
+      - '"paths" section must be sequence node but got alias node'

.github/actions/report-toolchain/action.yml

@@ -0,0 +1,76 @@
+name: Report compiler toolchain
+description: Report the activated compiler environment and compiler-selected linker
+
+inputs:
+  c-compiler:
+    description: C compiler command; defaults to CC or cc
+    required: false
+    default: ""
+  cxx-compiler:
+    description: C++ compiler command; defaults to CXX or c++
+    required: false
+    default: ""
+  fortran-compiler:
+    description: Fortran compiler command; defaults to FC or gfortran
+    required: false
+    default: ""
+  cuda-compiler:
+    description: CUDA compiler command; defaults to CUDACXX or nvcc when available
+    required: false
+    default: ""
+
+runs:
+  using: composite
+  steps:
+    - name: Report compiler toolchain
+      shell: bash
+      env:
+        INPUT_C_COMPILER: ${{ inputs.c-compiler }}
+        INPUT_CXX_COMPILER: ${{ inputs.cxx-compiler }}
+        INPUT_FORTRAN_COMPILER: ${{ inputs.fortran-compiler }}
+        INPUT_CUDA_COMPILER: ${{ inputs.cuda-compiler }}
+      run: |
+        set -euo pipefail
+
+        for variable in \
+          CONDA_PREFIX CC CXX FC CUDACXX \
+          CFLAGS CXXFLAGS FFLAGS CUDAFLAGS LDFLAGS
+        do
+          printf '%s=%s\n' "$variable" "${!variable:-<unset>}"
+        done
+
+        c_compiler=${INPUT_C_COMPILER:-${CC:-$(command -v cc || true)}}
+        cxx_compiler=${INPUT_CXX_COMPILER:-${CXX:-$(command -v c++ || true)}}
+        fortran_compiler=${INPUT_FORTRAN_COMPILER:-${FC:-$(command -v gfortran || true)}}
+        cuda_compiler=${INPUT_CUDA_COMPILER:-${CUDACXX:-$(command -v nvcc || true)}}
+
+        report_compiler() {
+          local language=$1
+          local compiler=$2
+          if [[ -z "$compiler" ]]; then
+            return
+          fi
+          printf '\n%s compiler: %s\n' "$language" "$compiler"
+          "$compiler" --version
+        }
+
+        report_compiler C "$c_compiler"
+        report_compiler C++ "$cxx_compiler"
+        report_compiler Fortran "$fortran_compiler"
+        report_compiler CUDA "$cuda_compiler"
+
+        if [[ -z "$cxx_compiler" ]]; then
+          printf 'A C++ compiler is required to identify the host linker.\n' >&2
+          exit 1
+        fi
+
+        linker=$("$cxx_compiler" -print-prog-name=ld)
+        if [[ "$linker" != /* ]]; then
+          linker=$(command -v "$linker" || true)
+        fi
+        if [[ -z "$linker" || ! -x "$linker" ]]; then
+          printf 'Could not resolve the C++ compiler-selected linker.\n' >&2
+          exit 1
+        fi
+
+        printf '\nC++ linker: %s\n' "$linker"; "$linker" --version || "$linker" -v

.github/workflows/model-test.yml

@@ -36,4 +36,4 @@ jobs:
         environment: default
 
     - name: Run model unit tests
-      run: pytest -v model/tests/test_model.py model/tests/test_utils.py
+      run: pytest -v model/tests/test_model.py model/tests/test_utils.py

.github/workflows/pyscf-skalaxc-parity.yml

@@ -0,0 +1,71 @@
+name: "PySCF-SkalaXC parity tests"
+
+on:
+  push:
+    branches: [main]
+    paths: &parity-test-paths
+      - '.github/workflows/pyscf-skalaxc-parity.yml'
+      - 'tests/**'
+      - 'skala/src/skala/**'
+      - 'SkalaXC/**'
+      - 'pixi.lock'
+      - 'pixi.toml'
+      - 'pyproject.toml'
+  pull_request:
+    branches: [main]
+    paths: *parity-test-paths
+  workflow_dispatch:
+
+permissions:
+  contents: read
+
+jobs:
+  test:
+    runs-on: ubuntu-latest
+    env:
+      OMP_NUM_THREADS: 4
+    steps:
+    - uses: actions/checkout@34e114876b0b11c390a56381ad16ebd13914f8d5 # v4
+      with:
+        submodules: recursive
+        persist-credentials: false
+
+    - name: Print CPU diagnostics
+      uses: ./.github/actions/cpu-diagnostics
+
+    - name: Setup Pixi
+      uses: ./.github/actions/setup-pixi
+      with:
+        environment: skalaxc-parity
+
+    - name: Configure SkalaXC
+      run: >-
+        cmake
+        -S SkalaXC
+        -B SkalaXC/build-pixi-parity
+        -G Ninja
+        -DCMAKE_BUILD_TYPE=Release
+        -DCMAKE_INSTALL_PREFIX=${{ github.workspace }}/SkalaXC/install-pixi-parity
+        -DSKALAXC_BUILD_FORTRAN=OFF
+        -DSKALAXC_BUILD_TESTS=OFF
+        -DSKALAXC_BUILD_EXAMPLES=OFF
+        -DSKALAXC_DOWNLOAD_MODELS=ON
+        -DSKALAXC_ENABLE_CUDA=OFF
+        -DSKALAXC_ENABLE_MPI=OFF
+        -DSKALAXC_ENABLE_OPENMP=ON
+
+    - name: Build and install SkalaXC
+      run: |
+        cmake --build SkalaXC/build-pixi-parity --parallel 2
+        cmake --install SkalaXC/build-pixi-parity --component Core
+
+    - name: Install SkalaXC Python binding
+      env:
+        SkalaXC_DIR: ${{ github.workspace }}/SkalaXC/install-pixi-parity/lib/cmake/SkalaXC
+        SKALAXC_PYTHON_LAYOUT: WHEEL
+      run: >-
+        python -m pip install SkalaXC/python
+        --no-build-isolation --no-deps --force-reinstall
+
+    - name: Run direct-binding parity tests
+      run: pytest -v tests/test_pyscf_skalaxc_parity.py

.github/workflows/skala-test.yml

@@ -120,4 +120,4 @@ jobs:
         environment: test-py312-pyscf214-torch213
 
     - name: Run profiling tests
-      run: pytest -v -m profiling skala/tests/
+      run: pytest -v -m profiling skala/tests/