fix slow operations in evm

status-im · Aug 1, 2023 · dc5907c · dc5907c
1 parent 9be5df9
commit dc5907c
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Showing 4 changed files with 17 additions and 14 deletions.
diff --git a/nimbus/evm/interpreter/op_handlers/oph_memory.nim b/nimbus/evm/interpreter/op_handlers/oph_memory.nim
@@ -27,8 +27,7 @@ import
   ./oph_defs,
   ./oph_helpers,
   eth/common,
-  stint,
-  strformat
+  stint
 
 {.push raises: [CatchableError].} # basically the annotation type of a `Vm2OpFn`
 
@@ -50,8 +49,7 @@ when evmc_enabled:
       gasCost  = c.gasCosts[Sstore].c_handler(newValue, gasParam)[0]
 
     c.gasMeter.consumeGas(
-      gasCost, &"SSTORE: {c.msg.contractAddress}[{slot}] " &
-              &"-> {newValue} ({currentValue})")
+      gasCost, "SSTORE")
 
 else:
   proc sstoreImpl(c: Computation, slot, newValue: UInt256) =
@@ -65,8 +63,7 @@ else:
         c.gasCosts[Sstore].c_handler(newValue, gasParam)
 
     c.gasMeter.consumeGas(
-      gasCost, &"SSTORE: {c.msg.contractAddress}[{slot}] " &
-              &"-> {newValue} ({currentValue})")
+      gasCost, "SSTORE")
     if gasRefund > 0:
       c.gasMeter.refundGas(gasRefund)
 
@@ -87,8 +84,7 @@ else:
       (gasCost, gasRefund) = c.gasCosts[Sstore].c_handler(newValue, gasParam)
 
     c.gasMeter.consumeGas(
-      gasCost, &"SSTORE EIP2200: {c.msg.contractAddress}[{slot}]" &
-              &" -> {newValue} ({currentValue})")
+      gasCost, "SSTORE EIP2200")
 
     if gasRefund != 0:
       c.gasMeter.refundGas(gasRefund)

diff --git a/nimbus/evm/memory.nim b/nimbus/evm/memory.nim
@@ -37,8 +37,9 @@ proc newMemory*(size: Natural): Memory =
   result.extend(0, size)
 
 proc read*(memory: var Memory, startPos: Natural, size: Natural): seq[byte] =
-  # TODO: use an openArray[byte]
-  result = memory.bytes[startPos ..< (startPos + size)]
+  result = newSeq[byte](size)
+  if size > 0:
+    copyMem(result[0].addr, memory.bytes[startPos].addr, size)
 
 when defined(evmc_enabled):
   proc readPtr*(memory: var Memory, startPos: Natural): ptr byte =

diff --git a/nimbus/evm/modexp.nim b/nimbus/evm/modexp.nim
@@ -183,6 +183,12 @@ proc modExp*(b, e, m: openArray[byte]): seq[byte] =
   var
     base, exp, modulo, res: mp_int
 
+  if m.len == 0:
+    return @[0.byte]
+
+  if e.len == 0:
+    return @[1.byte]
+
   if mp_init_multi(base, exp.addr, modulo.addr, nil) != MP_OKAY:
     return
 
@@ -192,7 +198,7 @@ proc modExp*(b, e, m: openArray[byte]): seq[byte] =
       # EVM special case 1
       # If m == 0: EVM returns 0.
       # If m == 1: we can shortcut that to 0 as well
-      mp_clear(modulo)
+      mp_clear_multi(base, exp.addr, modulo.addr, nil)
       return @[0.byte]
 
   if e.len > 0:
@@ -201,7 +207,7 @@ proc modExp*(b, e, m: openArray[byte]): seq[byte] =
       # EVM special case 2
       # If 0^0: EVM returns 1
       # For all x != 0, x^0 == 1 as well
-      mp_clear_multi(exp, modulo.addr, nil)
+      mp_clear_multi(base, exp.addr, modulo.addr, nil)
       return @[1.byte]
 
   if b.len > 0:

diff --git a/tests/fixtures/TracerTests/block46402.json b/tests/fixtures/TracerTests/block46402.json
@@ -283,7 +283,7 @@
             "0000000000000000000000000000000000000000000000000000000000000000",
             "0000000000000000000000000000000000000000000000000000000000000060"
           ],
-          "error": "Opcode Dispatch Error msg=Out of gas: Needed 20000 - Remaining 412 - Reason: SSTORE: 9a049f5d18c239efaa258af9f3e7002949a977a0[0] -> 924236965777326770894530693462975209021625492404 (0), depth=0",
+          "error": "Opcode Dispatch Error msg=Out of gas: Needed 20000 - Remaining 412 - Reason: SSTORE, depth=0",
           "gasCost": 0
         }
       ],
@@ -705,7 +705,7 @@
           "0000000000000000000000000000000000000000000000000000000000000000",
           "0000000000000000000000000000000000000000000000000000000000000060"
         ],
-        "error": "Opcode Dispatch Error msg=Out of gas: Needed 20000 - Remaining 412 - Reason: SSTORE: 9a049f5d18c239efaa258af9f3e7002949a977a0[0] -> 924236965777326770894530693462975209021625492404 (0), depth=0",
+        "error": "Opcode Dispatch Error msg=Out of gas: Needed 20000 - Remaining 412 - Reason: SSTORE, depth=0",
         "gasCost": 0
       }
     ]