chore: redo CI (#88)

Using GPU workers is only needed for running the tests. Use other
(way cheaper) machines for the other steps. This reduces the costs
by about 7.5x (from around 1300 to 170 credits).

Also the total runtime is about half now.

.circleci/config.yml

@@ -2,137 +2,62 @@ version: 2.1
 
 executors:
   default:
+    docker:
+      - image: cimg/rust:1.70
+    resource_class: small
+  gpu:
     machine:
       image: linux-cuda-12:2023.05.1
-    working_directory: ~/gpuci
-    resource_class: gpu.nvidia.medium
+    resource_class: gpu.nvidia.small
 
-restore-workspace: &restore-workspace
-  attach_workspace:
-    at: ~/
-
-restore-cache: &restore-cache
-  restore_cache:
-    keys:
-      - cargo-v0-{{ checksum "rust-toolchain" }}-{{ checksum "Cargo.toml" }}-{{ checksum "Cargo.lock" }}-{{ arch }}
-      - repo-source-{{ .Branch }}-{{ .Revision }}
-
-commands:
-  set-env-path:
+jobs:
+  test:
+    executor: gpu
     steps:
+      - checkout
       - run:
-          name: Set the PATH env variable
+          name: Install OpenCL
           command: |
-            echo 'export PATH="$HOME:~/.cargo/bin:/usr/local/cuda-11.2/bin:$PATH"' | tee --append $BASH_ENV
-            source $BASH_ENV
-
-  test_target:
-    parameters:
-      target:
-        type: string
-    steps:
-      - *restore-workspace
-      - *restore-cache
+            sudo apt update
+            sudo apt install ocl-icd-opencl-dev --no-install-recommends --yes
       - run:
-          name: Test (<< parameters.target >>)
-          command: TARGET=<< parameters.target >> cargo test
-          no_output_timeout: 15m
-
-jobs:
-
-  cargo_fetch:
-    executor: default
-    steps:
-      - checkout
-      - run: curl https://sh.rustup.rs -sSf | sh -s -- -y
-      - set-env-path
-      - run: echo $BASH_ENV
-      - run: echo $HOME
-      - run: cargo --version
-      - run: rustc --version
+          name: Install Rust
+          command: curl https://sh.rustup.rs -sSf | sh -s -- --default-toolchain $(cat rust-toolchain) --profile minimal -y
       - run:
-          name: Update submodules
-          command: git submodule update --init --recursive
+          name: Run tests
+          command: cargo test
       - run:
-          name: Calculate dependencies
-          command: cargo generate-lockfile
-      - restore_cache:
-          keys:
-            - cargo-v0-{{ checksum "rust-toolchain" }}-{{ checksum "Cargo.toml" }}-{{ checksum "Cargo.lock" }}-{{ arch }}
-      - run: cargo update
-      - run: cargo fetch
-      - run: rustup install $(cat rust-toolchain)
-      - run: rustup default $(cat rust-toolchain)
-      - run: rustc --version
-      - run: rm -rf .git
-      - persist_to_workspace:
-          root: ~/
-          paths:
-            - gpuci
-      - save_cache:
-          key: cargo-v0-{{ checksum "rust-toolchain" }}-{{ checksum "Cargo.toml" }}-{{ checksum "Cargo.lock" }}-{{ arch }}
-          paths:
-            - "~/.cargo"
-            - "~/.rustup"
-
-  test_x86_64-unknown-linux-gnu:
-    executor: default
-    steps:
-      - set-env-path
-      - run: sudo apt-get update -y
-      - run: apt-cache search opencl
-      - run: sudo apt install -y ocl-icd-opencl-dev
-      - test_target:
-          target: "x86_64-unknown-linux-gnu"
+          name: Run `add` example
+          command: cargo run --example add
 
   rustfmt:
     executor: default
     steps:
-      - *restore-workspace
-      - *restore-cache
-      - set-env-path
-      - run: echo 'export PATH="$HOME:~/.cargo/bin:$PATH"' >> $BASH_ENV
-      - run: source $BASH_ENV
+      - checkout
       - run:
           name: Run cargo fmt
           command: cargo fmt --all -- --check
 
   clippy:
     executor: default
     steps:
-      - *restore-workspace
-      - *restore-cache
-      - set-env-path
+      - checkout
       - run:
           name: Run cargo clippy
           command: cargo clippy --all-features --all-targets -- -D warnings
 
   build:
     executor: default
     steps:
-      - *restore-workspace
-      - *restore-cache
-      - set-env-path
+      - checkout
       - run:
           name: Run cargo release build
           command: cargo build --release
 
-  example:
-    executor: default
-    steps:
-      - *restore-workspace
-      - *restore-cache
-      - set-env-path
-      - run:
-          name: Run `add` example
-          command: cargo run --example add
-
   rustdoc:
     executor: default
     steps:
-      - *restore-workspace
-      - *restore-cache
-      - set-env-path
+      - checkout
       - run:
           name: Run rustdoc
           command: cargo rustdoc --all-features -- -D warnings
@@ -142,22 +67,8 @@ workflows:
 
   test:
     jobs:
-      - cargo_fetch
-      - rustfmt:
-          requires:
-            - cargo_fetch
-      - clippy:
-          requires:
-            - cargo_fetch
-      - test_x86_64-unknown-linux-gnu:
-          requires:
-            - cargo_fetch
-      - build:
-          requires:
-            - cargo_fetch
-      - example:
-          requires:
-            - cargo_fetch
-      - rustdoc:
-          requires:
-            - cargo_fetch
+      - rustfmt
+      - clippy
+      - test
+      - build
+      - rustdoc