Update BlockBaseFee to fit in 2 limbs

evm/src/fixed_recursive_verifier.rs

@@ -570,7 +570,7 @@ where
         let mut prod = builder.constant(F::ONE);
 
         // Add metadata writes.
-        let block_fields_without_beneficiary = [
+        let block_fields_without_beneficiary_and_basefee = [
             (
                 GlobalMetadata::BlockTimestamp,
                 public_values.block_metadata.block_timestamp,
@@ -591,16 +591,13 @@ where
                 GlobalMetadata::BlockChainId,
                 public_values.block_metadata.block_chain_id,
             ),
-            (
-                GlobalMetadata::BlockBaseFee,
-                public_values.block_metadata.block_base_fee,
-            ),
         ];
 
         let zero = builder.constant(F::ZERO);
         let one = builder.constant(F::ONE);
         let segment = builder.constant(F::from_canonical_u32(Segment::GlobalMetadata as u32));
 
+        // Include the block beneficiary.
         let row = builder.add_virtual_targets(13);
         // is_read
         builder.connect(row[0], zero);
@@ -629,7 +626,7 @@ where
         let combined = challenge.combine_base_circuit(builder, &row);
         prod = builder.mul(prod, combined);
 
-        block_fields_without_beneficiary.map(|(field, target)| {
+        block_fields_without_beneficiary_and_basefee.map(|(field, target)| {
             let row = builder.add_virtual_targets(13);
             // is_read
             builder.connect(row[0], zero);
@@ -651,6 +648,32 @@ where
             prod = builder.mul(prod, combined);
         });
 
+        // Include the block base fee.
+        let row = builder.add_virtual_targets(13);
+        // is_read
+        builder.connect(row[0], zero);
+        // context
+        builder.connect(row[1], zero);
+        // segment
+        builder.connect(row[2], segment);
+        // virtual
+        let field_target = builder.constant(F::from_canonical_usize(
+            GlobalMetadata::BlockBaseFee as usize,
+        ));
+        builder.connect(row[3], field_target);
+        // values
+        for j in 0..2 {
+            builder.connect(row[4 + j], public_values.block_metadata.block_base_fee[j]);
+        }
+        for j in 2..VALUE_LIMBS {
+            builder.connect(row[4 + j], zero);
+        }
+        // timestamp
+        builder.connect(row[12], one);
+
+        let combined = challenge.combine_base_circuit(builder, &row);
+        prod = builder.mul(prod, combined);
+
         // Add trie roots writes.
         let trie_fields = [
             (

evm/src/get_challenges.rs

@@ -74,7 +74,10 @@ fn observe_block_metadata<
         block_metadata.block_chain_id.as_u32(),
     ));
     challenger.observe_element(F::from_canonical_u32(
-        block_metadata.block_base_fee.as_u32(),
+        block_metadata.block_base_fee.as_u64() as u32,
+    ));
+    challenger.observe_element(F::from_canonical_u32(
+        (block_metadata.block_base_fee.as_u64() >> 32) as u32,
     ));
 }
 
@@ -94,7 +97,7 @@ fn observe_block_metadata_target<
     challenger.observe_element(block_metadata.block_difficulty);
     challenger.observe_element(block_metadata.block_gaslimit);
     challenger.observe_element(block_metadata.block_chain_id);
-    challenger.observe_element(block_metadata.block_base_fee);
+    challenger.observe_elements(&block_metadata.block_base_fee);
 }
 
 pub(crate) fn observe_public_values<

evm/src/proof.rs

@@ -120,7 +120,7 @@ impl PublicValuesTarget {
         buffer.write_target(block_difficulty)?;
         buffer.write_target(block_gaslimit)?;
         buffer.write_target(block_chain_id)?;
-        buffer.write_target(block_base_fee)?;
+        buffer.write_target_vec(&block_base_fee)?;
 
         Ok(())
     }
@@ -145,7 +145,7 @@ impl PublicValuesTarget {
             block_difficulty: buffer.read_target()?,
             block_gaslimit: buffer.read_target()?,
             block_chain_id: buffer.read_target()?,
-            block_base_fee: buffer.read_target()?,
+            block_base_fee: buffer.read_target_vec()?.try_into().unwrap(),
         };
 
         Ok(Self {
@@ -264,11 +264,11 @@ pub struct BlockMetadataTarget {
     pub block_difficulty: Target,
     pub block_gaslimit: Target,
     pub block_chain_id: Target,
-    pub block_base_fee: Target,
+    pub block_base_fee: [Target; 2],
 }
 
 impl BlockMetadataTarget {
-    const SIZE: usize = 11;
+    const SIZE: usize = 12;
 
     pub fn from_public_inputs(pis: &[Target]) -> Self {
         let block_beneficiary = pis[0..5].try_into().unwrap();
@@ -277,7 +277,7 @@ impl BlockMetadataTarget {
         let block_difficulty = pis[7];
         let block_gaslimit = pis[8];
         let block_chain_id = pis[9];
-        let block_base_fee = pis[10];
+        let block_base_fee = pis[10..12].try_into().unwrap();
 
         Self {
             block_beneficiary,
@@ -309,7 +309,9 @@ impl BlockMetadataTarget {
             block_difficulty: builder.select(condition, bm0.block_difficulty, bm1.block_difficulty),
             block_gaslimit: builder.select(condition, bm0.block_gaslimit, bm1.block_gaslimit),
             block_chain_id: builder.select(condition, bm0.block_chain_id, bm1.block_chain_id),
-            block_base_fee: builder.select(condition, bm0.block_base_fee, bm1.block_base_fee),
+            block_base_fee: core::array::from_fn(|i| {
+                builder.select(condition, bm0.block_base_fee[i], bm1.block_base_fee[i])
+            }),
         }
     }
 
@@ -326,7 +328,9 @@ impl BlockMetadataTarget {
         builder.connect(bm0.block_difficulty, bm1.block_difficulty);
         builder.connect(bm0.block_gaslimit, bm1.block_gaslimit);
         builder.connect(bm0.block_chain_id, bm1.block_chain_id);
-        builder.connect(bm0.block_base_fee, bm1.block_base_fee);
+        for i in 0..2 {
+            builder.connect(bm0.block_base_fee[i], bm1.block_base_fee[i])
+        }
     }
 }
 

evm/src/recursive_verifier.rs

@@ -548,7 +548,7 @@ pub(crate) fn add_virtual_block_metadata<F: RichField + Extendable<D>, const D:
     let block_difficulty = builder.add_virtual_public_input();
     let block_gaslimit = builder.add_virtual_public_input();
     let block_chain_id = builder.add_virtual_public_input();
-    let block_base_fee = builder.add_virtual_public_input();
+    let block_base_fee = builder.add_virtual_public_input_arr();
     BlockMetadataTarget {
         block_beneficiary,
         block_timestamp,
@@ -749,8 +749,13 @@ pub(crate) fn set_block_metadata_target<F, W, const D: usize>(
         block_metadata_target.block_chain_id,
         F::from_canonical_u32(block_metadata.block_chain_id.as_u32()),
     );
+    // Basefee fits in 2 limbs
     witness.set_target(
-        block_metadata_target.block_base_fee,
+        block_metadata_target.block_base_fee[0],
-        F::from_canonical_u32(block_metadata.block_base_fee.as_u32()),
+        F::from_canonical_u32(block_metadata.block_base_fee.as_u64() as u32),
+    );
+    witness.set_target(
+        block_metadata_target.block_base_fee[1],
+        F::from_canonical_u32((block_metadata.block_base_fee.as_u64() >> 32) as u32),
     );
 }