reduction of memory usage.

Author: dghgit

core/src/main/java/org/bouncycastle/pqc/crypto/mlkem/MLKEMIndCpa.java

@@ -277,11 +277,9 @@ private byte[] packCipherText(PolyVec b, Poly v)
 
     private void unpackCipherText(PolyVec b, Poly v, byte[] cipherText)
     {
-        byte[] compressedPolyVecCipherText = Arrays.copyOfRange(cipherText, 0, engine.getKyberPolyVecCompressedBytes());
-        b.decompressPolyVec(compressedPolyVecCipherText);
+        b.decompressPolyVec(cipherText);
 
-        byte[] compressedPolyCipherText = Arrays.copyOfRange(cipherText, engine.getKyberPolyVecCompressedBytes(), cipherText.length);
-        v.decompressPoly(compressedPolyCipherText);
+        v.decompressPoly(cipherText, engine.getKyberPolyVecCompressedBytes());
     }
 
     public byte[] packPublicKey(PolyVec publicKeyPolyVec, byte[] seed)

core/src/main/java/org/bouncycastle/pqc/crypto/mlkem/Poly.java

@@ -180,9 +180,9 @@ else if (polyCompressedBytes == 160)
         return r;
     }
 
-    public void decompressPoly(byte[] compressedPolyCipherText)
+    public void decompressPoly(byte[] compressedPolyCipherText, int polyCipherOff)
     {
-        int i, count = 0;
+        int i, count = polyCipherOff;
 
         if (engine.getKyberPolyCompressedBytes() == 128)
         {