Implement EIP160 #417

ethereum · Nov 2, 2016 · 2984b59 · 2984b59
1 parent 9b830b7
commit 2984b59
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diff --git a/ethereum/opcodes.py b/ethereum/opcodes.py
@@ -120,3 +120,5 @@
 CALL_CHILD_LIMIT_NUM = 63
 CALL_CHILD_LIMIT_DENOM = 64
 SUICIDE_SUPPLEMENTAL_GAS = 5000
+# Spurious dragon HF changes
+GEXPONENTBYTE_SUPPLEMENTAL_GAS = 40
diff --git a/ethereum/processblock.py b/ethereum/processblock.py
@@ -250,6 +250,8 @@ def __init__(self, block, tx):
         self.account_exists = block.account_exists
         self.post_homestead_hardfork = block.number >= block.config['HOMESTEAD_FORK_BLKNUM']
         self.post_anti_dos_hardfork = block.number >= block.config['ANTI_DOS_FORK_BLKNUM']
+        self.post_spurious_dragon_hardfork = \
+                block.number >= block.config['SPURIOUS_DRAGON_FORK_BLKNUM']
 
 
 def apply_msg(ext, msg):

diff --git a/ethereum/vm.py b/ethereum/vm.py
@@ -281,7 +281,10 @@ def vm_execute(ext, msg, code):
                 # fee for exponent is dependent on its bytes
                 # calc n bytes to represent exponent
                 nbytes = len(utils.encode_int(exponent))
-                expfee = nbytes * opcodes.GEXPONENTBYTE
+                expfee = nbytes * (opcodes.GEXPONENTBYTE +
+                    ext.post_spurious_dragon_hardforkf() * opcodes.GEXPONENTBYTE_SUPPLEMENTAL_GAS)
+                    # ^ EIP160: increase the gas cost of EXP from 10 + 10 per
+                    # byte in the exponent to 10 + 50 per byte in the exponent.
                 if compustate.gas < expfee:
                     compustate.gas = 0
                     return vm_exception('OOG EXPONENT')