feat(l2): add support for Pico backend

[xqft]

Motivation

To implement the Pico zkVM as a backend for L1 proving.

A particularity of Pico is that it requires compiling ethrex-prover in nightly (if the pico feature flag is enabled). This also propagates into ethrex-replay.

[github-actions]

Lines of code report

Total lines added: 89
Total lines removed: 0
Total lines changed: 89

Detailed view

+----------------------------------------------------------------+-------+------+
| File                                                           | Lines | Diff |
+----------------------------------------------------------------+-------+------+
| ethrex/crates/l2/prover/src/backend/mod.rs                     | 62    | +8   |
+----------------------------------------------------------------+-------+------+
| ethrex/crates/l2/prover/src/backend/pico.rs                    | 41    | +41  |
+----------------------------------------------------------------+-------+------+
| ethrex/crates/l2/prover/src/guest_program/build.rs             | 213   | +20  |
+----------------------------------------------------------------+-------+------+
| ethrex/crates/l2/prover/src/guest_program/src/lib.rs           | 29    | +4   |
+----------------------------------------------------------------+-------+------+
| ethrex/crates/l2/prover/src/guest_program/src/pico/src/main.rs | 10    | +10  |
+----------------------------------------------------------------+-------+------+
| ethrex/crates/l2/prover/src/lib.rs                             | 64    | +6   |
+----------------------------------------------------------------+-------+------+

[github-actions]

Benchmark Results Comparison

No significant difference was registered for any benchmark run.

Detailed Results

Benchmark Results: BubbleSort

Command	Mean [s]	Min [s]	Max [s]	Relative
main_revm_BubbleSort	2.998 ± 0.025	2.965	3.030	1.00 ± 0.02
main_levm_BubbleSort	3.103 ± 0.026	3.080	3.149	1.04 ± 0.02
pr_revm_BubbleSort	2.987 ± 0.051	2.945	3.091	1.00
pr_levm_BubbleSort	3.094 ± 0.027	3.070	3.152	1.04 ± 0.02

Benchmark Results: ERC20Approval

Command	Mean [ms]	Min [ms]	Max [ms]	Relative
main_revm_ERC20Approval	967.7 ± 8.5	958.1	984.5	1.00
main_levm_ERC20Approval	1092.7 ± 1.9	1090.3	1095.6	1.13 ± 0.01
pr_revm_ERC20Approval	979.2 ± 26.7	958.1	1031.4	1.01 ± 0.03
pr_levm_ERC20Approval	1089.9 ± 8.9	1078.5	1111.9	1.13 ± 0.01

Benchmark Results: ERC20Mint

Command	Mean [ms]	Min [ms]	Max [ms]	Relative
main_revm_ERC20Mint	132.7 ± 1.1	131.3	134.1	1.01 ± 0.01
main_levm_ERC20Mint	165.5 ± 1.4	163.4	167.7	1.26 ± 0.01
pr_revm_ERC20Mint	131.4 ± 0.7	130.6	132.5	1.00
pr_levm_ERC20Mint	164.1 ± 1.4	162.4	167.0	1.25 ± 0.01

Benchmark Results: ERC20Transfer

Command	Mean [ms]	Min [ms]	Max [ms]	Relative
main_revm_ERC20Transfer	232.7 ± 4.9	226.8	240.5	1.01 ± 0.02
main_levm_ERC20Transfer	280.2 ± 5.1	276.1	294.0	1.22 ± 0.03
pr_revm_ERC20Transfer	229.4 ± 2.3	226.9	234.5	1.00
pr_levm_ERC20Transfer	276.0 ± 1.8	272.9	279.5	1.20 ± 0.01

Benchmark Results: Factorial

Command	Mean [ms]	Min [ms]	Max [ms]	Relative
main_revm_Factorial	225.3 ± 0.5	224.4	226.4	1.01 ± 0.00
main_levm_Factorial	272.3 ± 2.0	270.8	276.3	1.22 ± 0.01
pr_revm_Factorial	223.9 ± 0.6	223.1	225.0	1.00
pr_levm_Factorial	270.8 ± 1.3	269.8	274.4	1.21 ± 0.01

Benchmark Results: FactorialRecursive

Command	Mean [s]	Min [s]	Max [s]	Relative
main_revm_FactorialRecursive	1.662 ± 0.052	1.537	1.732	1.00
main_levm_FactorialRecursive	8.263 ± 0.036	8.208	8.327	4.97 ± 0.16
pr_revm_FactorialRecursive	1.682 ± 0.026	1.632	1.721	1.01 ± 0.04
pr_levm_FactorialRecursive	8.281 ± 0.039	8.218	8.359	4.98 ± 0.16

Benchmark Results: Fibonacci

Command	Mean [ms]	Min [ms]	Max [ms]	Relative
main_revm_Fibonacci	207.3 ± 2.3	206.1	213.7	1.01 ± 0.01
main_levm_Fibonacci	268.8 ± 4.5	259.6	278.7	1.31 ± 0.02
pr_revm_Fibonacci	205.5 ± 0.8	204.2	207.2	1.00
pr_levm_Fibonacci	265.4 ± 1.6	263.8	268.5	1.29 ± 0.01

Benchmark Results: FibonacciRecursive

Command	Mean [ms]	Min [ms]	Max [ms]	Relative
main_revm_FibonacciRecursive	877.1 ± 6.9	862.9	884.2	1.17 ± 0.02
main_levm_FibonacciRecursive	747.7 ± 9.0	730.7	761.1	1.00
pr_revm_FibonacciRecursive	867.7 ± 8.1	849.5	875.8	1.16 ± 0.02
pr_levm_FibonacciRecursive	751.4 ± 4.7	745.6	759.7	1.00 ± 0.01

Benchmark Results: ManyHashes

Command	Mean [ms]	Min [ms]	Max [ms]	Relative
main_revm_ManyHashes	8.2 ± 0.0	8.2	8.3	1.00
main_levm_ManyHashes	9.2 ± 0.8	8.8	11.4	1.11 ± 0.10
pr_revm_ManyHashes	8.3 ± 0.1	8.2	8.4	1.00 ± 0.01
pr_levm_ManyHashes	9.0 ± 0.1	8.9	9.2	1.09 ± 0.01

Benchmark Results: MstoreBench

Command	Mean [ms]	Min [ms]	Max [ms]	Relative
main_revm_MstoreBench	266.0 ± 6.3	260.4	280.4	1.10 ± 0.03
main_levm_MstoreBench	242.9 ± 2.4	240.6	248.5	1.00 ± 0.02
pr_revm_MstoreBench	262.6 ± 3.9	258.4	268.3	1.08 ± 0.02
pr_levm_MstoreBench	242.5 ± 3.3	239.1	251.4	1.00

Benchmark Results: Push

Command	Mean [ms]	Min [ms]	Max [ms]	Relative
main_revm_Push	293.5 ± 1.6	291.0	295.6	1.01 ± 0.01
main_levm_Push	294.0 ± 0.7	292.9	295.2	1.01 ± 0.01
pr_revm_Push	292.0 ± 1.4	289.2	295.2	1.00
pr_levm_Push	305.3 ± 0.9	304.3	306.7	1.05 ± 0.01

Benchmark Results: SstoreBench_no_opt

Command	Mean [ms]	Min [ms]	Max [ms]	Relative
main_revm_SstoreBench_no_opt	167.1 ± 4.6	160.9	177.5	1.88 ± 0.06
main_levm_SstoreBench_no_opt	90.0 ± 1.7	87.9	92.0	1.02 ± 0.02
pr_revm_SstoreBench_no_opt	165.7 ± 3.6	160.4	168.9	1.87 ± 0.05
pr_levm_SstoreBench_no_opt	88.7 ± 1.2	87.6	92.0	1.00

[Copilot]

Pull request overview

This PR adds support for the Pico zkVM backend to the ethrex L2 prover infrastructure. Pico requires compilation with nightly Rust, which propagates the nightly requirement to ethrex-prover and ethrex-replay when the pico feature flag is enabled.

Key Changes:

• Added Pico backend implementation with prove, execute, and verify functions
• Integrated Pico guest program with rkyv serialization
• Updated CI workflows to support Pico compilation and testing
• Modified KZG API calls to use new from_slice methods

Reviewed changes

Copilot reviewed 16 out of 18 changed files in this pull request and generated 6 comments.

Show a summary per file

File	Description
crates/l2/prover/src/backend/pico.rs	New Pico backend implementation with prove/execute/verify functions
crates/l2/prover/src/guest_program/src/pico/src/main.rs	Pico guest program entry point using pico_sdk
crates/l2/prover/src/guest_program/src/pico/Cargo.toml	Dependencies for Pico guest program with patches for compatibility
crates/l2/prover/src/guest_program/build.rs	Build script to compile Pico program using cargo pico
crates/vm/levm/Cargo.toml	Added pico feature flag for LEVM
crates/common/crypto/kzg.rs	Updated kzg-rs API calls to use from_slice constructors
.github/workflows/tag_release.yaml	CI pipeline for building and releasing Pico artifacts
.github/workflows/pr-main_l2_prover.yaml	PR validation workflow for Pico backend

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