# Benchmark pipeline for performance regression detection.
#
# Runs on the weekly scheduled pipeline, with separate jobs per ISA target.
# EIGEN_BENCH_SCOPE selects the core subset or all benchmarks.  Results are
# analyzed using Welch's t-test against the last 30 runs stored on the
# perf-data branch.
# SPDX-FileCopyrightText: The Eigen Authors
# SPDX-License-Identifier: MPL-2.0

# ============================================================================
# Variables
# ============================================================================

variables:
  EIGEN_BENCH_BUILDDIR: .bench-build
  EIGEN_BENCH_REPETITIONS: "5"
  # Scope: "nightly" runs core subset, "weekly" runs all benchmarks.
  # The run script auto-promotes to "weekly" on Sundays so the full suite
  # runs once a week without a separate schedule.  Override via web UI or
  # a dedicated GitLab schedule with EIGEN_BENCH_SCOPE=weekly.
  EIGEN_BENCH_SCOPE: "nightly"

# ============================================================================
# Abstract bases
# ============================================================================

.bench:linux:base:
  image: ubuntu:22.04
  variables:
    EIGEN_CI_BUILDDIR: ${EIGEN_BENCH_BUILDDIR}
    EIGEN_CI_TARGET_ARCH: ""
    EIGEN_BENCH_ISA_FLAGS: ""
    EIGEN_BENCH_TARGET: ""
  before_script:
    - . ci/scripts/common.linux.before_script.sh
  rules: !reference [.rules:libeigen:scheduled-or-web, rules]

.bench:linux:build:
  extends: .bench:linux:base
  stage: benchmark
  needs: []
  script:
    - . ci/scripts/build.benchmark.sh
  artifacts:
    when: always
    name: "$CI_JOB_NAME_SLUG-$CI_COMMIT_REF_SLUG"
    paths:
      - ${EIGEN_BENCH_BUILDDIR}/
    exclude:
      - ${EIGEN_BENCH_BUILDDIR}/**/*.o
    expire_in: 2 days
  tags:
    - saas-linux-2xlarge-amd64

.bench:linux:run:
  extends: .bench:linux:base
  stage: benchmark
  script:
    - . ci/scripts/run.benchmark.sh
  artifacts:
    when: always
    name: "$CI_JOB_NAME_SLUG-$CI_COMMIT_REF_SLUG"
    paths:
      - ${EIGEN_BENCH_BUILDDIR}/results/
    expire_in: 30 days

# ============================================================================
# Build jobs (one per ISA target, all run in parallel)
# ============================================================================

bench:build:x86-64:sse:
  extends: .bench:linux:build
  variables:
    EIGEN_CI_C_COMPILER: gcc-10
    EIGEN_CI_CXX_COMPILER: g++-10
    EIGEN_CI_INSTALL: g++-10
    EIGEN_CI_TARGET_ARCH: x86_64
    EIGEN_BENCH_TARGET: x86-64-sse

bench:build:x86-64:avx2:
  extends: .bench:linux:build
  variables:
    EIGEN_CI_C_COMPILER: gcc-10
    EIGEN_CI_CXX_COMPILER: g++-10
    EIGEN_CI_INSTALL: g++-10
    EIGEN_CI_TARGET_ARCH: x86_64
    EIGEN_BENCH_TARGET: x86-64-avx2
    EIGEN_BENCH_ISA_FLAGS: "-mavx2 -mfma"

bench:build:aarch64:neon:
  extends: .bench:linux:build
  variables:
    EIGEN_CI_C_COMPILER: gcc-10
    EIGEN_CI_CXX_COMPILER: g++-10
    EIGEN_CI_INSTALL: g++-10
    EIGEN_CI_TARGET_ARCH: aarch64
    EIGEN_BENCH_TARGET: aarch64-neon
    EIGEN_BENCH_ISA_FLAGS: "-march=armv8.2-a+fp16"
  tags:
    - saas-linux-large-arm64

# ============================================================================
# Run jobs (one per ISA target, each depends on its build)
# ============================================================================

bench:run:x86-64:sse:
  extends: .bench:linux:run
  needs: [bench:build:x86-64:sse]
  variables:
    EIGEN_BENCH_TARGET: x86-64-sse
  tags:
    - saas-linux-2xlarge-amd64

bench:run:x86-64:avx2:
  extends: .bench:linux:run
  needs: [bench:build:x86-64:avx2]
  variables:
    EIGEN_BENCH_TARGET: x86-64-avx2
  tags:
    - saas-linux-2xlarge-amd64

bench:run:aarch64:neon:
  extends: .bench:linux:run
  needs: [bench:build:aarch64:neon]
  variables:
    EIGEN_BENCH_TARGET: aarch64-neon
  tags:
    - saas-linux-large-arm64

# ============================================================================
# Analysis: compare against historical data using Welch's t-test
# ============================================================================

bench:analyze:
  stage: benchmark
  image: python:3.11-slim
  needs:
    - job: bench:run:x86-64:sse
      artifacts: true
    - job: bench:run:x86-64:avx2
      artifacts: true
    - job: bench:run:aarch64:neon
      artifacts: true
  variables:
    EIGEN_CI_BUILDDIR: ${EIGEN_BENCH_BUILDDIR}
  before_script:
    - export DEBIAN_FRONTEND=noninteractive
    - apt-get update -qq && apt-get install -y --no-install-recommends git
    - pip install --quiet scipy
  script:
    - |
      status=0
      python3 ci/scripts/detect_regressions.py \
        --results-dir "${EIGEN_BENCH_BUILDDIR}/results/" \
        --perf-branch perf-data \
        --history-count 30 \
        --significance 0.01 \
        --min-change-pct 5.0 \
        --output-report "${EIGEN_BENCH_BUILDDIR}/results/regression_report.txt" || status=$?
      case "${status}" in
        0|1) ;;
        *) exit "${status}" ;;
      esac
      printf '%s\n' "${status}" > "${EIGEN_BENCH_BUILDDIR}/results/regression_exit_code.txt"
  artifacts:
    when: always
    paths:
      - ${EIGEN_BENCH_BUILDDIR}/results/
    reports:
      junit: ${EIGEN_BENCH_BUILDDIR}/results/regression_report.xml
    expire_in: 90 days
  tags:
    - saas-linux-small-amd64
  rules: !reference [.rules:libeigen:scheduled-or-web, rules]

# ============================================================================
# Storage and gating
# ============================================================================

bench:store-results:
  stage: deploy
  image: alpine:3.20
  needs:
    - job: bench:analyze
      artifacts: true
  before_script:
    - apk add --no-cache git python3
  script:
    - . ci/scripts/push_perf_data.sh
  variables:
    EIGEN_CI_BUILDDIR: ${EIGEN_BENCH_BUILDDIR}
  tags:
    - saas-linux-small-amd64
  rules: !reference [.rules:libeigen:scheduled-or-web:default-branch, rules]

bench:regression-gate:
  stage: deploy
  image: alpine:3.20
  needs:
    - job: bench:analyze
      artifacts: true
    - job: bench:store-results
      optional: true
  script:
    - code=$(cat "${EIGEN_BENCH_BUILDDIR}/results/regression_exit_code.txt")
    - test "${code}" != "1"
  variables:
    EIGEN_CI_BUILDDIR: ${EIGEN_BENCH_BUILDDIR}
  tags:
    - saas-linux-small-amd64
  rules: !reference [.rules:libeigen:scheduled-or-web, rules]