chore(l2): do not use docker to compile prover except on releases (#5315)

**Motivation**

<!-- Why does this pull request exist? What are its goals? -->
We use docker to generate reproducible guest program elfs. This slows
down a lot the compilation time (about 15 minutes in a Mac).

**Description**

<!-- A clear and concise general description of the changes this PR
introduces -->
Don't use docker by default but only when releasing binaries. The docker
build is triggered by setting the `PROVER_REPRODUCIBLE_BUILD` env var.

<!-- Link to issues: Resolves #111, Resolves #222 -->

---------

Co-authored-by: Copilot <175728472+Copilot@users.noreply.github.com>
Co-authored-by: ilitteri <ilitteri@fi.uba.ar>

Author: 3 people

.github/actions/install-risc0/action.yml

@@ -0,0 +1,15 @@
+name: "Install RISC0"
+description: "Install RISC0 Toolchain"
+
+runs:
+  using: "composite"
+  steps:
+    - name: Install RISC0
+      shell: bash
+      run: |
+        curl -L https://risczero.com/install | bash
+        ~/.risc0/bin/rzup install cargo-risczero 3.0.3
+        ~/.risc0/bin/rzup install risc0-groth16
+        ~/.risc0/bin/rzup install rust
+        ~/.risc0/bin/rzup install cpp
+        ~/.risc0/bin/rzup install r0vm 3.0.3

.github/workflows/pr-main_l2.yaml

@@ -69,11 +69,7 @@ jobs:
       - name: Install RISC0
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-        run: |
-          curl -L https://risczero.com/install | bash
-          ~/.risc0/bin/rzup install cargo-risczero 3.0.3
-          ~/.risc0/bin/rzup install risc0-groth16
-          ~/.risc0/bin/rzup install rust
+        uses: ./.github/actions/install-risc0
 
       - name: Create placeholder SP1 ELF
         run: |

.github/workflows/pr-main_l2_prover.yaml

@@ -30,17 +30,11 @@ jobs:
       - name: Add Rust Cache
         uses: Swatinem/rust-cache@v2
 
-      - name: RISC-V Risc0 toolchain install
+      - name: Install RISC0
         if: matrix.backend == 'risc0'
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-        # should be able to specify a version for `rzup install rust` (toolchain version)
-        # but it throws a "error decoding response body" in that case
-        run: |
-          curl -L https://risczero.com/install | bash
-          ~/.risc0/bin/rzup install cargo-risczero 3.0.3
-          ~/.risc0/bin/rzup install risc0-groth16
-          ~/.risc0/bin/rzup install rust
+        uses: ./.github/actions/install-risc0
 
       - name: RISC-V SP1 toolchain install
         if: matrix.backend == 'sp1'

.github/workflows/tag_release.yaml

@@ -18,6 +18,7 @@ permissions:
 env:
   REGISTRY: ghcr.io
   IMAGE_NAME: ${{ github.repository }}
+  PROVER_REPRODUCIBLE_BUILD: true
 
 jobs:
   build-ethrex:
@@ -96,11 +97,8 @@ jobs:
         if: ${{ matrix.platform == 'ubuntu-22.04' }}
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-        run: |
-          curl -L https://risczero.com/install | bash
-          ~/.risc0/bin/rzup install cargo-risczero 3.0.3
-          ~/.risc0/bin/rzup install risc0-groth16
-          ~/.risc0/bin/rzup install rust
+        uses: ./.github/actions/install-risc0
+
       - name: Install CUDA (only Linux x86 GPU)
         uses: Jimver/cuda-toolkit@v0.2.24
         if: ${{ matrix.platform == 'ubuntu-22.04' && matrix.stack == 'l2_gpu' }}
@@ -185,11 +183,7 @@ jobs:
         if: ${{ matrix.zkvm == 'risc0' }}
         env:
           GITHUB_TOKEN: ${{ secrets.GITHUB_TOKEN }}
-        run: |
-          curl -L https://risczero.com/install | bash
-          ~/.risc0/bin/rzup install cargo-risczero 3.0.3
-          ~/.risc0/bin/rzup install risc0-groth16
-          ~/.risc0/bin/rzup install rust
+        uses: ./.github/actions/install-risc0
 
       - name: Build ethrex elf - ${{ matrix.zkvm }}
         run: |

crates/l2/prover/src/guest_program/build.rs

@@ -19,15 +19,22 @@ fn build_risc0_program() {
         vec![]
     };
 
-    let docker_options = DockerOptionsBuilder::default()
-        .root_dir(format!("{}/../../../../../", env!("CARGO_MANIFEST_DIR")))
-        .build()
-        .unwrap();
-    let guest_options = GuestOptionsBuilder::default()
-        .features(features)
-        .use_docker(docker_options)
-        .build()
-        .unwrap();
+    let guest_options = if option_env!("PROVER_REPRODUCIBLE_BUILD").is_some() {
+        let docker_options = DockerOptionsBuilder::default()
+            .root_dir(format!("{}/../../../../../", env!("CARGO_MANIFEST_DIR")))
+            .build()
+            .unwrap();
+        GuestOptionsBuilder::default()
+            .features(features)
+            .use_docker(docker_options)
+            .build()
+            .unwrap()
+    } else {
+        GuestOptionsBuilder::default()
+            .features(features)
+            .build()
+            .unwrap()
+    };
 
     let built_guests = embed_methods_with_options(std::collections::HashMap::from([(
         "zkvm-risc0-program",
@@ -66,7 +73,7 @@ fn build_sp1_program() {
             output_directory: Some("./src/sp1/out".to_string()),
             elf_name: Some("riscv32im-succinct-zkvm-elf".to_string()),
             features,
-            docker: true,
+            docker: option_env!("PROVER_REPRODUCIBLE_BUILD").is_some(),
             tag: "v5.0.8".to_string(),
             workspace_directory: Some(format!("{}/../../../../../", env!("CARGO_MANIFEST_DIR"))),
             ..Default::default()