ci.yml

# CI design is minute-budget-conscious (see docs/ENVIRONMENT.md "CI" section):
# - One Linux job sweeps all x86 tiers sequentially: Highway builds once,
#   only corvus rebuilds per cap. A matrix would multiply job setup and
#   Highway builds for the same information.
# - Sanitizers run inside the same Linux job (one extra Debug build).
# - One macOS arm64 job: the expensive runner class, but the only one
#   producing new data (native NEON silicon).
# - One Windows job for TOOLCHAIN coverage, not tier coverage: MSVC is the
#   only compiler in the fleet that can produce Windows-specific diagnostics,
#   and the VS generator is the only multi-config generator we build under.
# - Docs-only changes skip CI entirely.
name: CI

on:
  push:
    branches: [main]
    paths-ignore: ['**.md', 'docs/**', 'LICENSE']
  pull_request:
    paths-ignore: ['**.md', 'docs/**', 'LICENSE']

concurrency:
  group: ci-${{ github.ref }}
  cancel-in-progress: true

permissions:
  contents: read

jobs:
  linux-x86:
    name: Linux x86-64 (tier sweep + sanitizers)
    runs-on: ubuntu-latest
    timeout-minutes: 20
    steps:
      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
        with:
          persist-credentials: false

      # Every tier is capped explicitly and the reached target is ASSERTED via
      # CORVUS_EXPECT_TARGET — hosted runner ISA is not guaranteed (some are
      # AVX-512-capable), so an uncapped run would silently test whatever
      # silicon it drew and skip the tier it claims. AVX10_2 belongs in BASE
      # even though HWY_BROKEN_AVX10_2 currently blocks it: that block is
      # version-gated on the toolchain and will expire, unlike this cap.
      - name: Tier sweep (AVX2, SSE4, SSSE3, SSE2)
        run: |
          BASE="HWY_AVX10_2|HWY_AVX3_SPR|HWY_AVX3_ZEN4|HWY_AVX3_DL|HWY_AVX3"
          for TIER in AVX2 SSE4 SSSE3 SSE2; do
            case $TIER in
              AVX2)  CAP="$BASE" ;;
              SSE4)  CAP="$BASE|HWY_AVX2" ;;
              SSSE3) CAP="$BASE|HWY_AVX2|HWY_SSE4" ;;
              SSE2)  CAP="$BASE|HWY_AVX2|HWY_SSE4|HWY_SSSE3" ;;
            esac
            echo "::group::$TIER (CORVUS_DISABLED_TARGETS=$CAP)"
            cmake -B build -G Ninja -DCORVUS_WERROR=ON \
              -DCORVUS_DISABLED_TARGETS="$CAP"
            cmake --build build
            CORVUS_EXPECT_TARGET="$TIER" \
              ctest --test-dir build --output-on-failure
            echo "::endgroup::"
          done

      # ctest hides output on success; log the measured numbers. Capped to AVX2
      # rather than left uncapped (the last sweep iteration leaves SSE-capped
      # binaries, so this must reconfigure anyway) — the report has to name the
      # tier it measured, which means pinning it rather than inheriting the
      # runner's.
      - name: ULP report
        run: |
          BASE="HWY_AVX10_2|HWY_AVX3_SPR|HWY_AVX3_ZEN4|HWY_AVX3_DL|HWY_AVX3"
          cmake -B build -G Ninja -DCORVUS_WERROR=ON \
            -DCORVUS_DISABLED_TARGETS="$BASE"
          cmake --build build
          export CORVUS_EXPECT_TARGET=AVX2
          # Dependency order, dd cores first: a foundation regression should
          # fail here under its own name, not a consumer's.
          ./build/tests/test_exp_dd tests/data/exp_dd_reference.txt
          ./build/tests/test_log_dd tests/data/log_dd_reference.txt
          ./build/tests/test_dd_special tests/data/dd_special_reference.txt
          ./build/tests/test_erf_ulp tests/data/erf_reference.txt
          ./build/tests/test_erfc_ulp tests/data/erfc_reference.txt
          ./build/tests/test_lgamma_ulp tests/data/lgamma_reference.txt
          ./build/tests/test_erfinv_ulp \
            tests/data/erfinv_reference.txt tests/data/erfcinv_reference.txt
          ./build/tests/test_gamma_ulp \
            tests/data/gamma_p_reference.txt tests/data/gamma_q_reference.txt
          ./build/tests/test_beta_ulp \
            tests/data/beta_p_reference.txt tests/data/beta_q_reference.txt
          ./build/tests/test_digamma_ulp tests/data/digamma_reference.txt
          ./build/tests/test_trigamma_ulp tests/data/trigamma_reference.txt
          ./build/tests/test_gammainv_ulp \
            tests/data/gammainv_p_reference.txt \
            tests/data/gammainv_q_reference.txt
          ./build/tests/test_betainv_ulp \
            tests/data/betainv_p_reference.txt \
            tests/data/betainv_q_reference.txt
          ./build/tests/test_bessel_ulp \
            tests/data/i0_reference.txt tests/data/i1_reference.txt \
            tests/data/i0e_reference.txt tests/data/i1e_reference.txt
          ./build/tests/test_lbeta_ulp tests/data/lbeta_reference.txt
          ./build/tests/test_trig_ulp \
            tests/data/cos_reference.txt tests/data/sin_reference.txt
          ./build/tests/test_exp_ulp tests/data/exp_reference.txt
          ./build/tests/test_log_ulp \
            tests/data/log_reference.txt tests/data/log1p_reference.txt

      # The examples self-verify and return non-zero on failure (see
      # examples/CMakeLists.txt — deliberately outside ctest so a green ctest
      # stays a pure accuracy statement). Run them from the AVX2-capped build
      # the ULP report leaves behind; sub-second each. (#25)
      - name: Run examples (smoke)
        run: |
          for ex in normal_distribution chi_squared_test gamma_mle_fit \
                    students_t von_mises_density log_space_counting; do
            echo "::group::$ex"
            ./build/examples/$ex
            echo "::endgroup::"
          done

      - name: Sanitizers (ASan+UBSan, Debug)
        run: |
          cmake -B build-san -G Ninja -DCMAKE_BUILD_TYPE=Debug \
            -DCORVUS_SANITIZE="address;undefined"
          cmake --build build-san
          UBSAN_OPTIONS=halt_on_error=1 \
            ctest --test-dir build-san --output-on-failure

      # -----------------------------------------------------------------
      # Install-contract smoke test — installed-path build, separate from
      # the tier-sweep dirs above. Builds the PINNED Highway (1.4.0, the
      # accuracy-audit version) into a prefix so find_package(hwy 1.4)
      # resolves it as a system install (CORVUS_HWY_PROVIDER=system),
      # which gates the install rules. Distro libhwy-dev is deliberately
      # NOT used: Ubuntu ships Highway 1.0.x, far below the audited 1.4
      # pin the version floor protects (see FindOrFetchHighway.cmake --
      # the floor is the accuracy-audit pin, not any single op).
      # -----------------------------------------------------------------
      # Cache the installed Highway prefix: building 1.4.0 from source costs
      # ~2-4 min per run. Key = pin + runner OS/arch; exact-match only (no
      # restore-keys) so a pin bump always rebuilds. This is the "add caching
      # only if minutes grow" trigger from the CI policy — the source build
      # of Highway is what grew the minutes.
      - name: Cache pinned Highway prefix
        id: cache-hwy
        uses: actions/cache@55cc8345863c7cc4c66a329aec7e433d2d1c52a9 # v6.1.0
        with:
          path: _hwy
          key: hwy-1.4.0-${{ runner.os }}-${{ runner.arch }}

      - name: Build pinned Highway into prefix
        if: steps.cache-hwy.outputs.cache-hit != 'true'
        run: |
          git clone --depth 1 --branch 1.4.0 https://github.com/google/highway.git _hwy-src
          cmake -S _hwy-src -B _hwy-src/build -G Ninja \
            -DCMAKE_BUILD_TYPE=Release \
            -DHWY_ENABLE_TESTS=OFF -DHWY_ENABLE_EXAMPLES=OFF \
            -DHWY_ENABLE_CONTRIB=ON -DBUILD_TESTING=OFF \
            -DCMAKE_INSTALL_PREFIX="$GITHUB_WORKSPACE/_hwy"
          cmake --build _hwy-src/build
          cmake --install _hwy-src/build

      - name: Configure, build, install corvus (system Highway)
        run: |
          cmake -B build-install -G Ninja -DCMAKE_BUILD_TYPE=Release \
            -DCMAKE_PREFIX_PATH="$GITHUB_WORKSPACE/_hwy" \
            | tee configure.log
          grep -q "using system Highway" configure.log
          cmake --build build-install
          cmake --install build-install --prefix "$GITHUB_WORKSPACE/_install"

      - name: Configure and build consumer_example against installed prefix
        run: |
          cmake -S consumer_example -B consumer_example/build -G Ninja \
            -DCMAKE_PREFIX_PATH="$GITHUB_WORKSPACE/_install;$GITHUB_WORKSPACE/_hwy"
          cmake --build consumer_example/build

      - name: Run consumer_example
        run: ./consumer_example/build/consumer_demo

      - name: pkg-config consumer (compile, link, run with the plain flags)
        run: |
          export PKG_CONFIG_PATH="$GITHUB_WORKSPACE/_install/lib/pkgconfig:$GITHUB_WORKSPACE/_hwy/lib/pkgconfig"
          pkg-config --exists --print-errors corvus
          pkg-config --cflags --libs corvus
          # Deliberately no --static: corvus.pc must carry Highway in
          # Requires (not Requires.private) because libcorvus.a is static.
          # Split into an array on purpose: the flags are separate arguments.
          read -ra pc_flags <<< "$(pkg-config --cflags --libs corvus)"
          g++ -o pc_consumer consumer_example/main.cpp "${pc_flags[@]}"
          ./pc_consumer

  # -------------------------------------------------------------------------
  # Windows / MSVC — toolchain coverage. This job deliberately produces NO new
  # tier information: Highway blocklists every AVX3* target under real MSVC
  # (HWY_BROKEN_MSVC), so dispatch tops out at AVX2 no matter how capable the
  # runner's silicon is. That is what makes CORVUS_EXPECT_TARGET=AVX2 stable
  # here without any capping — the blocklist pins the ceiling for us, and
  # since #36 corvus states the same cap itself (cmake/ToolchainGuard.cmake).
  #
  # What it *does* catch, and nothing else in this workflow can:
  #   - MSVC-only diagnostics (/W4 /WX via CORVUS_WERROR). Real precedent: the
  #     C4566 Unicode-docstring warnings found in the sibling Python bindings,
  #     and the C4996 getenv deprecation this job caught on its first run.
  #   - The multi-config generator path. A set_property(CACHE CMAKE_BUILD_TYPE)
  #     bug made the VS generator fail at configure while Ninja was fine, so
  #     both other jobs were blind to it. No -G is passed on purpose: CMake's
  #     default on Windows is the newest installed Visual Studio, which is both
  #     multi-config and version-agnostic as runner images move. It also needs
  #     no vcvars shell and no third-party setup action.
  #
  # Do NOT add -DCORVUS_MSVC_UNBLOCK_AVX512=ON here. It would make this job
  # dispatch AVX-512 and report a green "Windows passing" that reads as
  # AVX-512 validation, on a code path upstream Highway declares untested and
  # on runner silicon whose ISA level is not guaranteed. AVX-512 validation is
  # a manual stop on the Ryzen box; see docs/ACCURACY.md.
  # -------------------------------------------------------------------------
  windows-msvc:
    name: Windows x86-64 (MSVC toolchain)
    runs-on: windows-latest
    timeout-minutes: 25
    defaults:
      run:
        shell: bash
    steps:
      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
        with:
          persist-credentials: false

      # Multi-config: no CMAKE_BUILD_TYPE, hence --config/-C on build and test.
      - name: Configure (default VS generator, multi-config)
        run: cmake -B build -DCORVUS_WERROR=ON

      - name: Build
        run: cmake --build build --config Release

      - name: Test
        run: |
          CORVUS_EXPECT_TARGET=AVX2 \
            ctest --test-dir build -C Release --output-on-failure

      # Not new audit data (AVX2 duplicates the Linux row), but it keeps
      # ACCURACY.md's "MSVC reproduces these values" claim auditable in the log
      # rather than resting on one local measurement.
      - name: ULP report
        run: |
          export CORVUS_EXPECT_TARGET=AVX2
          # Dependency order, dd cores first: a foundation regression should
          # fail here under its own name, not a consumer's.
          ./build/tests/Release/test_exp_dd.exe tests/data/exp_dd_reference.txt
          ./build/tests/Release/test_log_dd.exe tests/data/log_dd_reference.txt
          ./build/tests/Release/test_dd_special.exe tests/data/dd_special_reference.txt
          ./build/tests/Release/test_erf_ulp.exe tests/data/erf_reference.txt
          ./build/tests/Release/test_erfc_ulp.exe tests/data/erfc_reference.txt
          ./build/tests/Release/test_lgamma_ulp.exe tests/data/lgamma_reference.txt
          ./build/tests/Release/test_erfinv_ulp.exe \
            tests/data/erfinv_reference.txt tests/data/erfcinv_reference.txt
          ./build/tests/Release/test_gamma_ulp.exe \
            tests/data/gamma_p_reference.txt tests/data/gamma_q_reference.txt
          ./build/tests/Release/test_beta_ulp.exe \
            tests/data/beta_p_reference.txt tests/data/beta_q_reference.txt
          ./build/tests/Release/test_digamma_ulp.exe tests/data/digamma_reference.txt
          ./build/tests/Release/test_trigamma_ulp.exe tests/data/trigamma_reference.txt
          ./build/tests/Release/test_gammainv_ulp.exe \
            tests/data/gammainv_p_reference.txt \
            tests/data/gammainv_q_reference.txt
          ./build/tests/Release/test_betainv_ulp.exe \
            tests/data/betainv_p_reference.txt \
            tests/data/betainv_q_reference.txt
          ./build/tests/Release/test_bessel_ulp.exe \
            tests/data/i0_reference.txt tests/data/i1_reference.txt \
            tests/data/i0e_reference.txt tests/data/i1e_reference.txt
          ./build/tests/Release/test_lbeta_ulp.exe tests/data/lbeta_reference.txt
          ./build/tests/Release/test_trig_ulp.exe \
            tests/data/cos_reference.txt tests/data/sin_reference.txt
          ./build/tests/Release/test_exp_ulp.exe tests/data/exp_reference.txt
          ./build/tests/Release/test_log_ulp.exe \
            tests/data/log_reference.txt tests/data/log1p_reference.txt

      # #36 toolchain guard, against a real mingw-w64 GCC (the runner image
      # ships one on PATH). Configure-only — no build, and the Highway checkout
      # from the MSVC configure above is reused — so the guard's probe and both
      # of its mingw outcomes are exercised for seconds, not a second job. The
      # verdict logic itself runs on every leg as the toolchain_guard ctest.
      - name: Toolchain guard (mingw GCC, configure-only)
        run: |
          g++ --version | head -1
          HWY_SRC="$PWD/build/_deps/highway-src"
          common=(-G Ninja -DCMAKE_CXX_COMPILER=g++ -DCORVUS_BUILD_TESTS=OFF
                  "-DFETCHCONTENT_SOURCE_DIR_HIGHWAY=$HWY_SRC")

          echo "::group::uncapped mingw GCC must be refused, naming the GCC PR"
          if cmake -B build-guard-reject "${common[@]}" > guard-reject.log 2>&1; then
            cat guard-reject.log
            echo "::error::uncapped mingw GCC configured; the #36 guard did not fire"
            exit 1
          fi
          cat guard-reject.log
          grep -q "GCC PR 126741" guard-reject.log
          grep -q "CORVUS_ALLOW_UNSUPPORTED_TOOLCHAIN" guard-reject.log
          echo "::endgroup::"

          echo "::group::mingw GCC capped to the 128-bit tiers must configure"
          cmake -B build-guard-capped "${common[@]}" \
            "-DCORVUS_DISABLED_TARGETS=(HWY_AVX2|(HWY_AVX2-1))"
          echo "::endgroup::"

  macos-arm64:
    name: macOS arm64 (NEON)
    runs-on: macos-latest
    timeout-minutes: 15
    steps:
      - uses: actions/checkout@3d3c42e5aac5ba805825da76410c181273ba90b1 # v7.0.1
        with:
          persist-credentials: false

      - name: Install Highway
        run: brew install highway

      # Native dispatch, but the tier is still asserted: this job is the sole
      # source of the NEON row in docs/ACCURACY.md, so if a runner-image change
      # ever moves dispatch (e.g. to NEON_BF16 on newer cores) that must fail
      # loudly and be revalidated, not silently relabel the audit record.
      - name: Build and test
        run: |
          cmake -B build -G Ninja -DCORVUS_WERROR=ON \
            -DCMAKE_PREFIX_PATH="$(brew --prefix)"
          cmake --build build
          CORVUS_EXPECT_TARGET=NEON \
            ctest --test-dir build --output-on-failure

      # ctest hides output on success; run the ULP gates directly so the
      # measured per-tier numbers land in the log for the audit record.
      - name: ULP report
        run: |
          export CORVUS_EXPECT_TARGET=NEON
          # This job is the only source of ACCURACY.md's NEON numbers.
          # Dependency order, dd cores first: a foundation regression should
          # fail here under its own name, not a consumer's.
          ./build/tests/test_exp_dd tests/data/exp_dd_reference.txt
          ./build/tests/test_log_dd tests/data/log_dd_reference.txt
          ./build/tests/test_dd_special tests/data/dd_special_reference.txt
          ./build/tests/test_erf_ulp tests/data/erf_reference.txt
          ./build/tests/test_erfc_ulp tests/data/erfc_reference.txt
          ./build/tests/test_lgamma_ulp tests/data/lgamma_reference.txt
          ./build/tests/test_erfinv_ulp \
            tests/data/erfinv_reference.txt tests/data/erfcinv_reference.txt
          ./build/tests/test_gamma_ulp \
            tests/data/gamma_p_reference.txt tests/data/gamma_q_reference.txt
          ./build/tests/test_beta_ulp \
            tests/data/beta_p_reference.txt tests/data/beta_q_reference.txt
          ./build/tests/test_digamma_ulp tests/data/digamma_reference.txt
          ./build/tests/test_trigamma_ulp tests/data/trigamma_reference.txt
          ./build/tests/test_gammainv_ulp \
            tests/data/gammainv_p_reference.txt \
            tests/data/gammainv_q_reference.txt
          ./build/tests/test_betainv_ulp \
            tests/data/betainv_p_reference.txt \
            tests/data/betainv_q_reference.txt
          ./build/tests/test_bessel_ulp \
            tests/data/i0_reference.txt tests/data/i1_reference.txt \
            tests/data/i0e_reference.txt tests/data/i1e_reference.txt
          ./build/tests/test_lbeta_ulp tests/data/lbeta_reference.txt
          ./build/tests/test_trig_ulp \
            tests/data/cos_reference.txt tests/data/sin_reference.txt
          ./build/tests/test_exp_ulp tests/data/exp_reference.txt
          ./build/tests/test_log_ulp \
            tests/data/log_reference.txt tests/data/log1p_reference.txt