Merge pull request #648 from ethereum/fix-eq-description

Update description of calldata in documentation

Author: msooseth

CHANGELOG.md

@@ -30,6 +30,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 - Better exponential simplification
 - Dumping of END states (.prop) files is now default for `--debug`
 - When cheatcode is missing, we produce a partial execution warning
+- Size of calldata can be up to 2**64, not 256. This is now reflected in the documentation
 
 ## Changed
 - Warnings now lead printing FAIL. This way, users don't accidentally think that

doc/src/equivalence.md

@@ -46,7 +46,8 @@ hevm equivalence \
     --code-a $(solc --bin-runtime "contract1.sol" | tail -n1) \
     --code-b $(solc --bin-runtime "contract2.sol" | tail -n1)
 ```
-
 If `--sig` is given, calldata is assumed to take the form of the function
-given. If left out, calldata is a fully abstract buffer of at most 256 bytes.
-
+given. If `--calldata` is provided, a specific, concrete calldata is used. If
+neither is provided, a fully abstract calldata of at most `2**64` byte is
+assumed. Note that a `2**64` byte calldata would go over the gas limit, and
+hence should cover all meaningful cases.