From de52e630e8a0ed832c53ad56804f4be60033f721 Mon Sep 17 00:00:00 2001
From: Nicholas Ward <npward@berkeley.edu>
Date: Fri, 17 Jun 2022 23:32:46 -0700
Subject: [PATCH] addressed comments

---
 evm/src/cpu/columns.rs         | 2 ++
 evm/src/memory/memory_stark.rs | 8 ++++----
 2 files changed, 6 insertions(+), 4 deletions(-)

diff --git a/evm/src/cpu/columns.rs b/evm/src/cpu/columns.rs
index 811a2841..8751398e 100644
--- a/evm/src/cpu/columns.rs
+++ b/evm/src/cpu/columns.rs
@@ -1,3 +1,4 @@
+// TODO: remove when possible.
 #![allow(dead_code)]
 
 use std::ops::Range;
@@ -165,6 +166,7 @@ pub(crate) const NUM_MEMORY_VALUE_LIMBS: usize = 8;
 
 pub(crate) const CLOCK: usize = SIMPLE_LOGIC_DIFF_INV + 1;
 
+
 // Uses_memop(i) is `F::ONE` iff this row includes a memory operation in its `i`th spot.
 const USES_MEMOP_START: usize = CLOCK + 1;
 pub const fn uses_memop(op: usize) -> usize {
diff --git a/evm/src/memory/memory_stark.rs b/evm/src/memory/memory_stark.rs
index 61b4f8d0..e7d63df2 100644
--- a/evm/src/memory/memory_stark.rs
+++ b/evm/src/memory/memory_stark.rs
@@ -370,11 +370,11 @@ impl<F: RichField + Extendable<D>, const D: usize> Stark<F, D> for MemoryStark<F
         yield_constr.constraint_transition(address_unchanged * (next_addr_virtual - addr_virtual));
 
         // Third set of ordering constraints: range-check difference in the column that should be increasing.
-        let range_check_value = context_first_change * (next_addr_context - addr_context - one)
+        let computed_range_check = context_first_change * (next_addr_context - addr_context - one)
             + segment_first_change * (next_addr_segment - addr_segment - one)
             + virtual_first_change * (next_addr_virtual - addr_virtual - one)
             + address_unchanged * (next_timestamp - timestamp - one);
-        yield_constr.constraint_transition(range_check - range_check_value);
+        yield_constr.constraint_transition(range_check - computed_range_check);
 
         // Enumerate purportedly-ordered log.
         for i in 0..8 {
@@ -497,12 +497,12 @@ impl<F: RichField + Extendable<D>, const D: usize> Stark<F, D> for MemoryStark<F
         };
         let timestamp_range_check = builder.mul_extension(address_unchanged, timestamp_diff);
 
-        let range_check_value = {
+        let computed_range_check = {
             let mut sum = builder.add_extension(context_range_check, segment_range_check);
             sum = builder.add_extension(sum, virtual_range_check);
             builder.add_extension(sum, timestamp_range_check)
         };
-        let range_check_diff = builder.sub_extension(range_check, range_check_value);
+        let range_check_diff = builder.sub_extension(range_check, computed_range_check);
         yield_constr.constraint_transition(builder, range_check_diff);
 
         // Enumerate purportedly-ordered log.