Fix kernel codehash discrepancy (0xPolygonZero#1400)

topos-protocol · Dec 1, 2023 · 32d0096 · 32d0096
1 parent 5572da3
commit 32d0096
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Showing 4 changed files with 38 additions and 29 deletions.
diff --git a/evm/src/cpu/kernel/asm/mpt/hex_prefix.asm b/evm/src/cpu/kernel/asm/mpt/hex_prefix.asm
@@ -67,20 +67,20 @@ remaining_bytes:
     SWAP1 SUB DUP1
     // stack: num_nibbles - parity, num_nibbles - parity, U256_MAX, packed_nibbles, rlp_pos, ret_dest
     %div_const(2)
-    // stack: remaining_bytes, num_nibbles - parity, U256_MAX, packed_nibbles, rlp_pos, ret_dest
+    // stack: rem_bytes, num_nibbles - parity, U256_MAX, packed_nibbles, rlp_pos, ret_dest
     SWAP2 SWAP1
-    // stack: num_nibbles - parity, U256_MAX, remaining_bytes, packed_nibbles, rlp_pos, ret_dest
+    // stack: num_nibbles - parity, U256_MAX, rem_bytes, packed_nibbles, rlp_pos, ret_dest
     %mul_const(4)
-    // stack: 4*(num_nibbles - parity), U256_MAX, remaining_bytes, packed_nibbles, rlp_pos, ret_dest
+    // stack: 4*(num_nibbles - parity), U256_MAX, rem_bytes, packed_nibbles, rlp_pos, ret_dest
     PUSH 256 SUB
-    // stack: 256 - 4*(num_nibbles - parity), U256_MAX, remaining_bytes, packed_nibbles, rlp_pos, ret_dest
+    // stack: 256 - 4*(num_nibbles - parity), U256_MAX, rem_bytes, packed_nibbles, rlp_pos, ret_dest
     SHR
-    // stack: mask, remaining_bytes, packed_nibbles, rlp_pos, ret_dest
+    // stack: mask, rem_bytes, packed_nibbles, rlp_pos, ret_dest
     SWAP1 SWAP2
     AND
     %stack
-        (remaining_nibbles, remaining_bytes, rlp_pos) ->
-        (rlp_pos, remaining_nibbles, remaining_bytes)
+        (remaining_nibbles, rem_bytes, rlp_pos) ->
+        (rlp_pos, remaining_nibbles, rem_bytes)
     %mstore_unpacking_rlp
     SWAP1
     JUMP
@@ -95,9 +95,13 @@ rlp_header_medium:
     // rlp_pos += 1
     %increment
 
-    %stack
-        (rlp_pos, num_nibbles, packed_nibbles, terminated, retdest) ->
-        (rlp_pos, num_nibbles, packed_nibbles, terminated, remaining_bytes, num_nibbles, packed_nibbles, retdest)
+    // stack: rlp_pos, num_nibbles, packed_nibbles, terminated, retdest
+    SWAP3 DUP3 DUP3
+    // stack: num_nibbles, packed_nibbles, terminated, num_nibbles, packed_nibbles, rlp_pos, retdest
+    PUSH remaining_bytes
+    // stack: remaining_bytes, num_nibbles, packed_nibbles, terminated, num_nibbles, packed_nibbles, rlp_pos, retdest
+    SWAP4 SWAP5 SWAP6
+    // stack: rlp_pos, num_nibbles, packed_nibbles, terminated, remaining_bytes, num_nibbles, packed_nibbles, retdest
 
     %jump(first_byte)
 
@@ -118,9 +122,12 @@ rlp_header_large:
     // rlp_pos += 2
     %add_const(2)
 
-    %stack
-        (rlp_pos, num_nibbles, packed_nibbles, terminated, retdest) ->
-        (rlp_pos, num_nibbles, packed_nibbles, terminated, remaining_bytes, num_nibbles, packed_nibbles, retdest)
+    // stack: rlp_pos, num_nibbles, packed_nibbles, terminated, retdest
+    SWAP3 DUP3 DUP3
+    // stack: num_nibbles, packed_nibbles, terminated, num_nibbles, packed_nibbles, rlp_pos, retdest
+    PUSH remaining_bytes
+    // stack: remaining_bytes, num_nibbles, packed_nibbles, terminated, num_nibbles, packed_nibbles, rlp_pos, retdest
+    SWAP4 SWAP5 SWAP6
+    // stack: rlp_pos, num_nibbles, packed_nibbles, terminated, remaining_bytes, num_nibbles, packed_nibbles, retdest
 
     %jump(first_byte)
-
diff --git a/evm/src/cpu/kernel/tests/kernel_consistency.rs b/evm/src/cpu/kernel/tests/kernel_consistency.rs
@@ -0,0 +1,16 @@
+use anyhow::Result;
+use ethereum_types::U256;
+
+use crate::cpu::kernel::aggregator::{combined_kernel, KERNEL};
+use crate::cpu::kernel::interpreter::Interpreter;
+use crate::memory::segments::Segment;
+
+#[test]
+fn test_kernel_code_hash_consistency() -> Result<()> {
+    for _ in 0..10 {
+        let kernel2 = combined_kernel();
+        assert_eq!(kernel2.code_hash, KERNEL.code_hash);
+    }
+
+    Ok(())
+}
diff --git a/evm/src/cpu/kernel/tests/mod.rs b/evm/src/cpu/kernel/tests/mod.rs
@@ -10,6 +10,7 @@ mod core;
 mod ecc;
 mod exp;
 mod hash;
+mod kernel_consistency;
 mod log;
 mod mpt;
 mod packing;

diff --git a/evm/src/generation/mod.rs b/evm/src/generation/mod.rs
@@ -191,19 +191,6 @@ fn apply_metadata_and_tries_memops<F: RichField + Extendable<D>, const D: usize>
     state.traces.memory_ops.extend(ops);
 }
 
-fn initialize_kernel_code<F: RichField + Extendable<D>, const D: usize>(
-    state: &mut GenerationState<F>,
-) {
-    for (i, &byte) in enumerate(KERNEL.code.iter()) {
-        let address = MemoryAddress {
-            context: 0,
-            segment: Segment::Code as usize,
-            virt: i,
-        };
-        state.memory.set(address, byte.into());
-    }
-}
-
 pub fn generate_traces<F: RichField + Extendable<D>, const D: usize>(
     all_stark: &AllStark<F, D>,
     inputs: GenerationInputs,
@@ -219,8 +206,6 @@ pub fn generate_traces<F: RichField + Extendable<D>, const D: usize>(
 
     apply_metadata_and_tries_memops(&mut state, &inputs);
 
-    initialize_kernel_code(&mut state);
-
     timed!(timing, "simulate CPU", simulate_cpu(&mut state)?);
 
     assert!(