modexp cleanup

GeneralStateTests.md

@@ -394,7 +394,7 @@ OK: 3/3 Fail: 0/3 Skip: 0/3
 + call_then_create2_successful_then_returndatasize.json           OK
 + create2InitCodes.json                                           OK
 + create2SmartInitCode.json                                       OK
-  create2callPrecompiles.json                                     Skip
++ create2callPrecompiles.json                                     OK
 + create2checkFieldsInInitcode.json                               OK
 + create2collisionBalance.json                                    OK
 + create2collisionCode.json                                       OK
@@ -413,7 +413,7 @@ OK: 3/3 Fail: 0/3 Skip: 0/3
 + returndatacopy_following_successful_create.json                 OK
 + returndatasize_following_successful_create.json                 OK
 ```
-OK: 41/44 Fail: 0/44 Skip: 3/44
+OK: 42/44 Fail: 0/44 Skip: 2/44
 ## stCreateTest
 ```diff
 + CREATE_AcreateB_BSuicide_BStore.json                            OK
@@ -2645,4 +2645,4 @@ OK: 133/133 Fail: 0/133 Skip: 0/133
 OK: 130/130 Fail: 0/130 Skip: 0/130
 
 ---TOTAL---
-OK: 2342/2447 Fail: 0/2447 Skip: 105/2447
+OK: 2343/2447 Fail: 0/2447 Skip: 104/2447

nimbus/vm/precompiles.nim

@@ -133,10 +133,6 @@ proc identity*(computation: BaseComputation) =
 proc modExpInternal(computation: BaseComputation, base_len, exp_len, mod_len: int, T: type StUint) =
   template rawMsg: untyped {.dirty.} =
     computation.msg.data
-  let
-    base = rawMsg.rangeToPadded[:T](96, 95 + base_len, base_len)
-    exp = rawMsg.rangeToPadded[:T](96 + base_len, 95 + base_len + exp_len, exp_len)
-    modulo = rawMsg.rangeToPadded[:T](96 + base_len + exp_len, 95 + base_len + exp_len + mod_len, mod_len)
 
   block: # Gas cost
     func gasModExp_f(x: Natural): int =
@@ -170,6 +166,11 @@ proc modExpInternal(computation: BaseComputation, base_len, exp_len, mod_len: in
     computation.gasMeter.consumeGas(gasFee, reason="ModExp Precompile")
 
   block: # Processing
+    let
+      base = rawMsg.rangeToPadded[:T](96, 95 + base_len, base_len)
+      exp = rawMsg.rangeToPadded[:T](96 + base_len, 95 + base_len + exp_len, exp_len)
+      modulo = rawMsg.rangeToPadded[:T](96 + base_len + exp_len, 95 + base_len + exp_len + mod_len, mod_len)
+
     # TODO: specs mentions that we should return in "M" format
     #       i.e. if Base and exp are uint512 and Modulo an uint256
     #       we should return a 256-bit big-endian byte array
@@ -187,11 +188,11 @@ proc modExpInternal(computation: BaseComputation, base_len, exp_len, mod_len: in
                     # If m == 0: EVM returns 0.
                     # If m == 1: we can shortcut that to 0 as well
                     zero()
-                 elif exp.isZero():
+                elif exp.isZero():
                     # If 0^0: EVM returns 1
                     # For all x != 0, x^0 == 1 as well
                     one()
-                 else:
+                else:
                     powmod(base, exp, modulo).toByteArrayBE
 
     # maximum output len is the same as mod_len
@@ -209,6 +210,7 @@ proc modExp*(computation: BaseComputation) =
   # Parsing the data
   template rawMsg: untyped {.dirty.} =
     computation.msg.data
+
   let # lengths Base, Exponent, Modulus
     base_len = rawMsg.rangeToPadded[:Uint256](0, 31).safeInt
     exp_len = rawMsg.rangeToPadded[:Uint256](32, 63).safeInt

tests/test_generalstate_failing.nim

@@ -14,7 +14,6 @@
 func allowedFailingGeneralStateTest*(folder, name: string): bool =
   let allowedFailingGeneralStateTests = @[
     "modexp.json",
-    "create2callPrecompiles.json",
     "create2noCash.json",
   ]
   result = name in allowedFailingGeneralStateTests