raising costs for encode/decode

ergoplatform · Nov 18, 2024 · eb50ab4 · eb50ab4
1 parent e374229
commit eb50ab4
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Showing 2 changed files with 7 additions and 5 deletions.
diff --git a/core/shared/src/main/scala/sigma/SigmaDsl.scala b/core/shared/src/main/scala/sigma/SigmaDsl.scala
@@ -739,9 +739,9 @@ trait SigmaDslBuilder {
   def groupGenerator: GroupElement
 
   /**
-    * @return big integer provided as input approximately encoded using NBits,
+    * @return NBits-encoded approximate representation of given big integer,
     *         see (https://bitcoin.stackexchange.com/questions/57184/what-does-the-nbits-value-represent)
-    *         for format details
+    *         for NBits format details
     */
   def encodeNbits(bi: BigInt): Long
 

diff --git a/data/shared/src/main/scala/sigma/ast/methods.scala b/data/shared/src/main/scala/sigma/ast/methods.scala
@@ -1845,15 +1845,17 @@ case object SGlobalMethods extends MonoTypeMethods {
       "Decode a number from big endian bytes.",
       ArgInfo("first", "Bytes which are big-endian encoded number."))
 
-  private lazy val EnDecodeNBitsCost = FixedCost(JitCost(5)) // the same cost for nbits encoding and decoding
+  private lazy val EncodeNBitsCost = FixedCost(JitCost(25)) // the same cost for nbits encoding and decoding
+
+  private lazy val DecodeNBitsCost = FixedCost(JitCost(50)) // the same cost for nbits encoding and decoding
 
   lazy val encodeNBitsMethod: SMethod = SMethod(
-    this, "encodeNbits", SFunc(Array(SGlobal, SBigInt), SLong), 6, EnDecodeNBitsCost)
+    this, "encodeNbits", SFunc(Array(SGlobal, SBigInt), SLong), 6, EncodeNBitsCost)
     .withIRInfo(MethodCallIrBuilder)
     .withInfo(MethodCall, "Encode big integer number as nbits", ArgInfo("bigInt", "Big integer"))
 
   lazy val decodeNBitsMethod: SMethod = SMethod(
-    this, "decodeNbits", SFunc(Array(SGlobal, SLong), SBigInt), 7, EnDecodeNBitsCost)
+    this, "decodeNbits", SFunc(Array(SGlobal, SLong), SBigInt), 7, DecodeNBitsCost)
     .withIRInfo(MethodCallIrBuilder)
     .withInfo(MethodCall, "Decode nbits-encoded big integer number", ArgInfo("nbits", "NBits-encoded argument"))