solidity/test/formal/signed_integer_cleanup_function.py

42 lines
936 B
Python

from opcodes import SIGNEXTEND
from rule import Rule
from util import BVSignedCleanupFunction, BVSignedUpCast
from z3 import BitVec, BitVecVal, Concat
"""
Overflow checked signed integer multiplication.
"""
n_bits = 256
# Check that YulUtilFunction::cleanupFunction cleanup matches BVSignedCleanupFunction
for type_bits in range(8,256,8):
rule = Rule()
# Input vars
X = BitVec('X', n_bits)
arg = BitVecVal(type_bits / 8 - 1, n_bits)
cleaned_reference = BVSignedCleanupFunction(X, type_bits)
cleaned = SIGNEXTEND(arg, X)
rule.check(cleaned, cleaned_reference)
# Check that BVSignedCleanupFunction properly cleans up values.
for type_bits in range(8,256,8):
rule = Rule()
# Input vars
X_short = BitVec('X', type_bits)
dirt = BitVec('dirt', n_bits - type_bits)
X = BVSignedUpCast(X_short, n_bits)
X_dirty = Concat(dirt, X_short)
X_cleaned = BVSignedCleanupFunction(X_dirty, type_bits)
rule.check(X, X_cleaned)