feat: parallel gtest (#5498)

Gtests take a relatively long time to run, and avm_tests will start to
take longer with the introduction of more lookups.

This uses the [gtest-parallel](https://github.com/google/gtest-parallel)
script to run the bb tests in parallel.

In some tests we get a 50% improvement in test times, while others
remain mostly the same (it's mostly down to the structure of the test
binary)

---------

Co-authored-by: ludamad <adam.domurad@gmail.com>

barretenberg/cpp/dockerfiles/Dockerfile.x86_64-linux-clang-assert

@@ -24,8 +24,14 @@ COPY . .
 # Build everything to ensure everything builds. All tests will be run from the result of this build.
 RUN ./format.sh check && cmake --preset clang16 -DCMAKE_BUILD_TYPE=RelWithAssert -DCI=ON && cmake --build --preset clang16
 RUN srs_db/download_grumpkin.sh
+RUN git clone --depth=1 https://github.com/google/gtest-parallel.git
+RUN cd gtest-parallel && git checkout 96f4f904922f9bf66689e749c40f314845baaac8
 
 FROM ubuntu:lunar
-RUN apt update && apt install curl libstdc++6 -y
+RUN apt update && apt install curl libstdc++6 python3.11-full -y
 COPY --from=builder /usr/src/barretenberg/cpp/srs_db /usr/src/barretenberg/cpp/srs_db
 COPY --from=builder /usr/src/barretenberg/cpp/build/bin /usr/src/barretenberg/cpp/build/bin
+# Copy gtest-parallel
+COPY --from=builder /usr/src/barretenberg/cpp/gtest-parallel /usr/src/barretenberg/cpp/build/gtest-parallel
+# Cache dir needed for gtest-parallel
+RUN mkdir -p /root/.cache

barretenberg/cpp/scripts/avm-tests.sh

@@ -15,4 +15,4 @@ docker run --rm -t $IMAGE_URI /bin/sh -c "\
   cd /usr/src/barretenberg/cpp; \
   srs_db/download_ignition.sh 1; \
   cd build; \
-  ./bin/vm_tests;"
+  ./gtest-parallel/gtest-parallel ./bin/vm_tests --workers=32;"

barretenberg/cpp/scripts/bb-tests.sh

@@ -40,12 +40,12 @@ TESTS=(
   polynomials_tests
   srs_tests
 )
-TESTS_STR="${TESTS[@]}"
+TESTS_STR="${TESTS[@]/#/./bin/}"
 
 docker run --rm -t $IMAGE_URI /bin/sh -c "\
   set -xe; \
   cd /usr/src/barretenberg/cpp; \
   srs_db/download_ignition.sh 1; \
   srs_db/download_grumpkin.sh; \
   cd build; \
-  for BIN in $TESTS_STR; do ./bin/\$BIN; done"
+  echo $TESTS_STR | xargs gtest-parallel/gtest-parallel --worker=32;"

barretenberg/cpp/scripts/run_tests

@@ -12,9 +12,9 @@ shift
 shift
 
 $(aws ecr get-login --region us-east-2 --no-include-email) 2> /dev/null
-
 # use the image rebuild patterns to compute a content hash, use this to get a URI
 REPOSITORY=barretenberg-x86_64-linux-clang-assert
+
 export PATH="$PATH:$(git rev-parse --show-toplevel)/build-system/scripts"
 IMAGE_URI=$(calculate_image_uri $REPOSITORY)
 retry docker pull $IMAGE_URI
@@ -25,9 +25,14 @@ if [ -f "$TESTS" ]; then
   TESTS=$(cat $TESTS | tr '\n' ' ')
 fi
 
+# Convert the string it an array so we can process as args to gtest-parallel
+IFS=' ' read -r -a TEST_ARRAY <<< $TESTS
+# Prepend ./bin/ and append any args (e.g. gTest Filters)
+TESTS_STR="${TEST_ARRAY[@]/#/./bin/}"
+TESTS_STR="${TESTS_STR[@]/%/ ${@}}"
 docker run --rm -t $IMAGE_URI /bin/sh -c "\
   set -xe; \
   /usr/src/barretenberg/cpp/srs_db/download_ignition.sh $NUM_TRANSCRIPTS; \
   /usr/src/barretenberg/cpp/srs_db/download_grumpkin.sh; \
   cd /usr/src/barretenberg/cpp/build; \
-  for BIN in $TESTS; do ./bin/\$BIN $@; done"
+  echo $TESTS_STR | xargs gtest-parallel/gtest-parallel --worker=32;"