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#!/usr/bin/env python3
# pip3 install pyevmasm
from pyevmasm import instruction_tables
#print(instruction_tables.keys())
def asm(x):
return [instruction_tables['istanbul'][i].opcode for i in x]
push_opcodes = asm(["PUSH%d" % i for i in range(1,33)])
stop_opcodes = asm(["STOP", "JUMP", "RETURN", "INVALID"])
caller_opcodes = asm(["CALLER"])
blacklist_ops = set([
"ADDRESS", "BALANCE", "BLOCKHASH",
"CALL", "CALLCODE", "CHAINID", "COINBASE",
"CREATE", "CREATE2", "DELEGATECALL", "DIFFICULTY",
"EXTCODESIZE", "EXTCODECOPY", "EXTCODEHASH",
"GASLIMIT", "GASPRICE", "NUMBER",
"ORIGIN", "REVERT", "SELFBALANCE", "SELFDESTRUCT",
"SLOAD", "SSTORE", "STATICCALL", "TIMESTAMP"])
whitelist_opcodes = []
for x in instruction_tables['istanbul']:
if x.name not in blacklist_ops:
whitelist_opcodes.append(x.opcode)
pushmask = 0
for x in push_opcodes:
pushmask |= 1 << x
stopmask = 0
for x in stop_opcodes:
stopmask |= 1 << x
stoplist = [0]*256
procmask = 0
for i in range(256):
if i in whitelist_opcodes and \
i not in push_opcodes and \
i not in stop_opcodes and \
i not in caller_opcodes:
# can skip this opcode
stoplist[i] = 1
else:
procmask |= 1 << i
# PUSH1 through PUSH4, can't skip in slow
for i in range(0x60, 0x64):
stoplist[i] = i-0x5e
rr = "uint256[8] memory opcodeSkippableBytes = [\n"
for i in range(0, 0x100, 0x20):
ret = "uint256(0x"
for j in range(i, i+0x20, 1):
ret += ("%02X" % stoplist[j])
rr += ret+"),\n"
rr = rr[:-2] + "];"
print(rr)
print("// Mask to gate opcode specific cases")
print("uint256 opcodeGateMask = ~uint256(0x%x);" % procmask)
print("// Halting opcodes")
print("uint256 opcodeHaltingMask = ~uint256(0x%x);" % stopmask)
print("// PUSH opcodes")
print("uint256 opcodePushMask = ~uint256(0x%x);" % pushmask)