fix: add more constraints to the cpu chip

Author: felicityin

.github/workflows/ci.yml

@@ -17,7 +17,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v4
-      - uses: dtolnay/rust-toolchain@stable
+      - uses: dtolnay/rust-toolchain@nightly
         with:
           components: rustfmt
       - run: cargo fmt --all -- --check

LICENSE

@@ -1,6 +1,6 @@
 The MIT License (MIT)
 
-Copyright (c) 2023 felicityin
+Copyright (c) 2025 felicityin
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal

README.md

@@ -2,7 +2,7 @@
 
 > This repo is inspired by [SP1](https://github.com/succinctlabs/sp1) and [zkMIPS](https://github.com/zkMIPS/zkMIPS).
 
-zkvm-brainfuck is a ZK-VM for the Brainfuck language.
+zkvm-brainfuck is a ZK-VM for the Brainfuck language, built on [Plonky3](https://github.com/Plonky3/Plonky3).
 
 - Designed as a register machine instead of a stack machine with RAM.
 - Compared to SP1, this system employs a single shard and produces only core proofs.

crates/core/machine/src/alu/mod.rs

@@ -19,6 +19,9 @@ use crate::utils::{next_power_of_two, zeroed_f_vec};
 /// The number of main trace columns for `AddSubChip`.
 pub const NUM_ADD_SUB_COLS: usize = size_of::<AddSubCols<u8>>();
 
+#[derive(Default)]
+pub struct AddSubChip;
+
 /// The column layout for the chip.
 #[derive(AlignedBorrow, Default, Clone, Copy)]
 #[repr(C)]
@@ -190,9 +193,6 @@ where
     }
 }
 
-#[derive(Default)]
-pub struct AddSubChip;
-
 #[cfg(test)]
 mod tests {
     use p3_koala_bear::KoalaBear;

crates/core/machine/src/cpu/air.rs

@@ -57,6 +57,8 @@ where
         builder.assert_bool(local.is_memory_instr);
         builder.assert_bool(local.is_io);
         builder.assert_bool(local.is_mv_immutable);
+        builder.assert_bool(local.mv_accessed);
+        builder.assert_bool(local.next_mv_accessed);
     }
 }
 

crates/core/machine/src/utils/prove.rs

@@ -36,6 +36,7 @@ where
     // Setup the runtime.
     let mut runtime = Executor::new(program, input);
 
+    // Execute the program to collect trace events.
     runtime.run().map_err(BfCoreProverError::ExecutionError)?;
 
     // Prove the program.

crates/derive/src/lib.rs

@@ -266,8 +266,8 @@ pub fn machine_air_derive(input: TokenStream) -> TokenStream {
 
             let mut new_generics = generics.clone();
             let where_clause = new_generics.make_where_clause();
-            if eval_trait_bound.is_some() {
-                let predicate: WherePredicate = syn::parse_str(&eval_trait_bound.unwrap()).unwrap();
+            if let Some(eval_trait_bound) = eval_trait_bound {
+                let predicate: WherePredicate = syn::parse_str(&eval_trait_bound).unwrap();
                 where_clause.predicates.push(predicate);
             }