Update EIP-7545: clarify precompile interface

Merged by EIP-Bot.

EIPS/eip-7545.md

@@ -2,7 +2,7 @@
 eip: 7545
 title: Verkle proof verification precompile
 description: Add a precompile to help dapps verify verkle proofs
-author: Guillaume Ballet (@gballet), ...
+author: Guillaume Ballet (@gballet), Diederik Loerakker (@protolambda)
 discussions-to: https://ethereum-magicians.org/t/verkle-proof-verification-precompile/16274
 status: Draft
 type: Standards Track
@@ -24,20 +24,27 @@ The key words "MUST", "MUST NOT", "REQUIRED", "SHALL", "SHALL NOT", "SHOULD", "S
 
 A precompiled contract is added at address `0x21`, wrapping the stateless ethereum proof verification function.
 
-The precompile `input` requires 4 items concatenated:
+The precompile's `input` is the tightly packed concatenation of the following fields:
 
-  * `version` (1 byte) specifies which version of the stateless proof verification function should be used
-  * `proof_data_location` (32 bytes) is a memory address where the start of the proof data can be found
-  * `proof_data_size` (8 bytes) specifies the length of the proof data.
+  * `version` (1 byte) specifies which version of the stateless proof verification function should be used. Version 0 is used for an MPT and version 1 is used for the polynomial commitment scheme multiproof used in [EIP-6800](./eip-6800.md).
   * `state_root` (32 bytes) specifies the state root that the proof is proving against.
+  * `proof_data` (arbitrary long) is the proof data.
 
 Pseudo-code behavior of the precompile:
 
 ```python
-def proof_verification_precompile(version, loc, size, root):
+def proof_verification_precompile(input):
+    version = input[0]
+    state_root = input[1:33]
+    proof_data = input[33:33+proof_data_size]
+
     if version == 0:
-        proof = deserialize_proof(root, memory[loc:loc+size])
-        return verify_multiproof_pcs(proof)
+        proof = deserialize_proof(state_root, proof_data)
+        return verify_mpt_multiproof(proof)
+
+    if version == 1:
+        proof = deserialize_proof(state_root, proof_data)
+        return verify_pcs_multiproof(proof)
 
     return 0
 ```
@@ -82,7 +89,9 @@ TODO
 
 ## Reference Implementation
 
-TODO
+WIP
+
+ * First implementation in Optimism, pull request #192 of ethereum-optimism/op-geth by @protolambda
 
 ## Security Considerations