From bf21b278d812ef1212d1367e526dbd2033034ef5 Mon Sep 17 00:00:00 2001
From: Linda Guiga <lindaguiga3@gmail.com>
Date: Tue, 5 Sep 2023 08:22:53 +0100
Subject: [PATCH] Apply comments

---
 evm/src/cpu/kernel/asm/core/create_receipt.asm       |  5 ++---
 .../cpu/kernel/asm/mpt/hash/hash_trie_specific.asm   | 12 +++++-------
 .../cpu/kernel/asm/mpt/load/load_trie_specific.asm   |  2 +-
 3 files changed, 8 insertions(+), 11 deletions(-)

diff --git a/evm/src/cpu/kernel/asm/core/create_receipt.asm b/evm/src/cpu/kernel/asm/core/create_receipt.asm
index 32f64494..586ea5bb 100644
--- a/evm/src/cpu/kernel/asm/core/create_receipt.asm
+++ b/evm/src/cpu/kernel/asm/core/create_receipt.asm
@@ -57,9 +57,8 @@ process_receipt_after_bloom:
     // Write transaction type if necessary. RLP_RAW contains, at index 0, the current transaction type.
     PUSH 0
     %mload_kernel(@SEGMENT_RLP_RAW)
-    DUP1
-    // stack: first_txn_byte, first_txn_byte, receipt_ptr, payload_len, status, new_cum_gas, txn_nb, new_cum_gas, txn_nb, retdest
-    %eq_const(1) %jumpi(receipt_nonzero_type)
+    // stack: first_txn_byte, receipt_ptr, payload_len, status, new_cum_gas, txn_nb, new_cum_gas, txn_nb, retdest
+    DUP1 %eq_const(1) %jumpi(receipt_nonzero_type)
     DUP1 %eq_const(2) %jumpi(receipt_nonzero_type)
     // If we are here, we are dealing with a legacy transaction, and we do not need to write the type.
     POP
diff --git a/evm/src/cpu/kernel/asm/mpt/hash/hash_trie_specific.asm b/evm/src/cpu/kernel/asm/mpt/hash/hash_trie_specific.asm
index 5b40225c..6b057a49 100644
--- a/evm/src/cpu/kernel/asm/mpt/hash/hash_trie_specific.asm
+++ b/evm/src/cpu/kernel/asm/mpt/hash/hash_trie_specific.asm
@@ -108,9 +108,10 @@ global encode_receipt:
     // either RLP(RLP(receipt)) for Legacy transactions or RLP(txn_type||RLP(receipt)) for transactions of type 1 or 2.
     // First encode the wrapper prefix.
     DUP2 %mload_trie_data
-    // stack: first_byte, rlp_pos, value_ptr, retdest
-    // The first byte is either the transaction type or the first byte of the RLP encoding.
-    DUP1 PUSH 3 GT %jumpi(encode_nonzero_receipt_type)
+    // stack: first_value, rlp_pos, value_ptr, retdest
+    // The first value is either the transaction type or the payload length.
+    // Since the receipt contains at least the 256-bytes long bloom filter, payload_len > 3.
+    DUP1 %lt_const(3) %jumpi(encode_nonzero_receipt_type)
     // If we are here, then the first byte is the payload length.
     %rlp_list_len
     // stack: rlp_receipt_len, rlp_pos, value_ptr, retdest
@@ -254,10 +255,7 @@ encode_nonzero_receipt_type:
     %mstore_rlp
     %increment
     // stack: rlp_pos, txn_type, old_rlp_pos, value_ptr, retdest
-    SWAP1 POP
-    // stack: rlp_pos, old_rlp_pos, value_ptr, retdest
-    SWAP1 POP
-    // stack: rlp_pos, value_ptr, retdest
+    %stack (rlp_pos, txn_type, old_rlp_pos, value_ptr, retdest) -> (rlp_pos, value_ptr, retdest)
     // We replace `value_ptr` with `paylaod_len_ptr` so we can encode the rest of the data more easily
     SWAP1 %increment SWAP1
     // stack: rlp_pos, payload_len_ptr, retdest
diff --git a/evm/src/cpu/kernel/asm/mpt/load/load_trie_specific.asm b/evm/src/cpu/kernel/asm/mpt/load/load_trie_specific.asm
index 213469cc..9ac51773 100644
--- a/evm/src/cpu/kernel/asm/mpt/load/load_trie_specific.asm
+++ b/evm/src/cpu/kernel/asm/mpt/load/load_trie_specific.asm
@@ -37,7 +37,7 @@ global mpt_load_receipt_trie_value:
     PROVER_INPUT(mpt) DUP1 %append_to_trie_data
     // If the first byte is less than 3, then it is the transaction type, equal to either 1 or 2. 
     // In that case, we still need to load the payload length.
-    PUSH 3 GT %jumpi(mpt_load_payload_len)
+    %lt_const(3) %jumpi(mpt_load_payload_len)
     
 mpt_load_after_type:
     // Load status.