[ci] add gitlab pipeline for criterion benchmarks

.gitlab-ci.yml

@@ -0,0 +1,51 @@
+# paritytech/wasmi
+
+stages:
+  - benchmark
+
+default:
+  retry:
+    max: 2
+    when:
+      - runner_system_failure
+      - unknown_failure
+      - api_failure
+
+.rust-info-script:                 &rust-info-script
+  - rustup show
+  - cargo --version
+  - rustup +nightly show
+  - cargo +nightly --version
+  - cargo spellcheck --version
+  - bash --version
+  - sccache -s
+
+.kubernetes-env:                   &kubernetes-env
+  image:                           "paritytech/ci-linux:production"
+  tags:
+    - kubernetes-parity-build
+
+.docker-env:                       &docker-env
+  image:                           "paritytech/ci-linux:production"
+  before_script:
+    - *rust-info-script
+  interruptible:                   true
+  tags:
+    - linux-docker
+
+# benchmark
+criterion-benchmark:
+  stage:                           benchmark
+  rules:
+  - if: $CI_COMMIT_REF_NAME =~ /^[0-9]+$/                   # PRs
+  <<:                              *docker-env
+  script:
+    - git fetch
+    - git submodule update --init --recursive
+    - git checkout master
+    # on master
+    - cargo bench --bench benches -- --noplot --save-baseline master | tee bench-report-master.txt
+    # on PR
+    - git checkout $CI_COMMIT_SHA
+    - cargo bench --bench benches -- --noplot --baseline master | tee bench-report-pr.txt
+    - bash ./scripts/ci/benchmarks-report.sh bench-report-master.txt bench-report-pr.txt

scripts/ci/benchmarks-report.sh

@@ -0,0 +1,91 @@
+#!/bin/bash
+
+# Takes raw reports from
+# "cargo bench --bench benches -- --noplot --save-baseline master" output as 1st argument
+# "cargo bench --bench benches -- --noplot --baseline master" output as 2nd argument
+# Parses them to json and posts formatted results to PR on a GitHub as a comment
+set -eu
+set -o pipefail
+
+PR_COMMENTS_URL="https://api.github.com/repos/paritytech/wasmi/issues/${CI_COMMIT_BRANCH}/comments"
+
+# master report to json
+echo "PARSING MASTER REPORT"
+sed -e 's/^Found.*//g' \
+    -e 's/^\s\+[[:digit:]].*$//g' \
+    -e 's/\//_/g' \
+    -e 's/^[a-z0-9_]\+/"&": {/g' \
+    -e 's/time:\s\+\[.\{10\}/"time": "/g' \
+    -e 's/.\{10\}\]/"},/g' \
+    -e '1s/^/{\n/g' \
+    -e '/^$/d' \
+    -e 's/  */ /g' \
+    -e 's/^ *\(.*\) *$/\1/' $1 \
+    | sed -z 's/.$//' \
+    | sed -e '$s/.$/}/g' \
+    | tee target/criterion/output_master.json
+
+# PR report to json
+sed -e 's/^Found.*//g' \
+    -e 's/^\s\+[[:digit:]].*//g' \
+    -e 's/\//_/g' \
+    -e 's/^[a-z0-9_]\+/"&": {/g' \
+    -e 's/time:\s\+\[.\{10\}/"time": "/g' \
+    -e 's/.\{10\}\]$/",/g' \
+    -e 's/change:\s.\{10\}/"change":"/g' \
+    -e 's/\s[-+].*$/",/g' \
+    -e 's/\(No\|Ch\).*$/"perf_change":":white_circle:"},/' \
+    -e 's/Performance has regressed./"perf_change":":red_circle:"},/' \
+    -e 's/Performance has improved./"perf_change":":green_circle:"},/' \
+    -e '1s/^/{\n/g' \
+    -e '/^$/d' \
+    -e 's/  */ /g' \
+    -e 's/^ *\(.*\) *$/\1/' $2 \
+    | sed -z 's/.$//' \
+    | sed -e '$s/.$/}/g' \
+    | tee target/criterion/output_pr.json
+
+cd target/criterion
+
+# Prepare report table
+for d in */; do
+    d=${d::-1}
+    echo -n "| \`${d}\` "\
+         "| $(cat output_master.json | jq .${d}.time | tr -d '"') "\
+         "| $(cat output_pr.json | jq .${d}.time | tr -d '"') "\
+         "| $(cat output_pr.json | jq .${d}.perf_change | tr -d '"') "\
+         "$(cat output_pr.json | jq .${d}.change | tr -d '"') |\n" >> bench-final-report.txt
+done
+
+RESULT=$(cat bench-final-report.txt)
+
+# Check whether comment from paritytech-cicd-pr already exists
+EXISTING_COMMENT_URL=$(curl --silent $PR_COMMENTS_URL \
+                       | jq -r ".[] \
+                       | select(.user.login == \"paritytech-cicd-pr\") \
+                       | .url" \
+                       | head -n1)
+
+# If there is already a comment by the user `paritytech-cicd-pr` in the PR which triggered
+# this run, then we can just edit this comment (using `PATCH` instead of `POST`).
+REQUEST_TYPE="POST"
+if [ ! -z "$EXISTING_COMMENT_URL" ]; then
+   REQUEST_TYPE="PATCH";
+   PR_COMMENTS_URL="$EXISTING_COMMENT_URL"
+fi
+
+echo "Comment will be posted here $PR_COMMENTS_URL"
+
+# POST/PATCH comment to the PR
+curl -X ${REQUEST_TYPE} ${PR_COMMENTS_URL} -v \
+    -H "Cookie: logged_in=no" \
+    -H "Authorization: token ${GITHUB_PR_TOKEN}" \
+    -H "Content-Type: application/json; charset=utf-8" \
+    -d $"{ \
+\"body\": \
+\"## CRITERION BENCHMARKS ## \n\n \
+|BENCHMARK|MASTER|PR|Diff|\n \
+|---|---|---|---|\n \
+${RESULT}\n\n \
+[Link to pipeline](${CI_JOB_URL}) \" \
+}"