diff --git a/asm/src/main/java/dev/openrs2/asm/InsnListUtils.java b/asm/src/main/java/dev/openrs2/asm/InsnListUtils.java
index db68fa6fd9..dafa458f68 100644
--- a/asm/src/main/java/dev/openrs2/asm/InsnListUtils.java
+++ b/asm/src/main/java/dev/openrs2/asm/InsnListUtils.java
@@ -32,7 +32,7 @@ public final class InsnListUtils {
 			}
 
 			insn = insn.getPrevious();
-		} while (insn != null && insn.getType() != AbstractInsnNode.LABEL && !InsnNodeUtils.hasSideEffects(insn));
+		} while (insn != null && insn.getType() != AbstractInsnNode.LABEL && InsnNodeUtils.isPure(insn));
 
 		return false;
 	}
diff --git a/asm/src/main/java/dev/openrs2/asm/InsnNodeUtils.java b/asm/src/main/java/dev/openrs2/asm/InsnNodeUtils.java
index 55dc463b9e..ae6fefe77f 100644
--- a/asm/src/main/java/dev/openrs2/asm/InsnNodeUtils.java
+++ b/asm/src/main/java/dev/openrs2/asm/InsnNodeUtils.java
@@ -119,7 +119,7 @@ public final class InsnNodeUtils {
 		}
 	}
 
-	public static boolean hasSideEffects(AbstractInsnNode insn) {
+	public static boolean isPure(AbstractInsnNode insn) {
 		var opcode = insn.getOpcode();
 		switch (opcode) {
 		case -1:
@@ -147,7 +147,7 @@ public final class InsnNodeUtils {
 		case Opcodes.FLOAD:
 		case Opcodes.DLOAD:
 		case Opcodes.ALOAD:
-			return false;
+			return true;
 		case Opcodes.IALOAD:
 		case Opcodes.LALOAD:
 		case Opcodes.FALOAD:
@@ -170,7 +170,7 @@ public final class InsnNodeUtils {
 		case Opcodes.BASTORE:
 		case Opcodes.CASTORE:
 		case Opcodes.SASTORE:
-			return true;
+			return false;
 		case Opcodes.POP:
 		case Opcodes.POP2:
 		case Opcodes.DUP:
@@ -226,9 +226,9 @@ public final class InsnNodeUtils {
 		case Opcodes.LOR:
 		case Opcodes.IXOR:
 		case Opcodes.LXOR:
-			return false;
-		case Opcodes.IINC:
 			return true;
+		case Opcodes.IINC:
+			return false;
 		case Opcodes.I2L:
 		case Opcodes.I2F:
 		case Opcodes.I2D:
@@ -249,7 +249,7 @@ public final class InsnNodeUtils {
 		case Opcodes.FCMPG:
 		case Opcodes.DCMPL:
 		case Opcodes.DCMPG:
-			return false;
+			return true;
 		case Opcodes.IFEQ:
 		case Opcodes.IFNE:
 		case Opcodes.IFLT:
@@ -275,22 +275,22 @@ public final class InsnNodeUtils {
 		case Opcodes.DRETURN:
 		case Opcodes.ARETURN:
 		case Opcodes.RETURN:
-			return true;
-		case Opcodes.GETSTATIC:
 			return false;
+		case Opcodes.GETSTATIC:
+			return true;
 		case Opcodes.PUTSTATIC:
 		case Opcodes.GETFIELD:
 			/* might throw NPE */
 		case Opcodes.PUTFIELD:
-			return true;
+			return false;
 		case Opcodes.INVOKEVIRTUAL:
 		case Opcodes.INVOKESPECIAL:
 		case Opcodes.INVOKESTATIC:
 		case Opcodes.INVOKEINTERFACE:
 		case Opcodes.INVOKEDYNAMIC:
-			return true;
-		case Opcodes.NEW:
 			return false;
+		case Opcodes.NEW:
+			return true;
 		case Opcodes.NEWARRAY:
 		case Opcodes.ANEWARRAY:
 			/* arrays might be created with negative size */
@@ -298,15 +298,15 @@ public final class InsnNodeUtils {
 			/* might throw NPE */
 		case Opcodes.ATHROW:
 		case Opcodes.CHECKCAST:
-			return true;
-		case Opcodes.INSTANCEOF:
 			return false;
+		case Opcodes.INSTANCEOF:
+			return true;
 		case Opcodes.MONITORENTER:
 		case Opcodes.MONITOREXIT:
 		case Opcodes.MULTIANEWARRAY:
 		case Opcodes.IFNULL:
 		case Opcodes.IFNONNULL:
-			return true;
+			return false;
 		}
 
 		throw new IllegalArgumentException();
diff --git a/deob/src/main/java/dev/openrs2/deob/transform/DummyArgTransformer.java b/deob/src/main/java/dev/openrs2/deob/transform/DummyArgTransformer.java
index 0e3144d003..fc4476d5a2 100644
--- a/deob/src/main/java/dev/openrs2/deob/transform/DummyArgTransformer.java
+++ b/deob/src/main/java/dev/openrs2/deob/transform/DummyArgTransformer.java
@@ -387,7 +387,7 @@ public final class DummyArgTransformer extends Transformer {
 				}
 				break;
 			default:
-				if (InsnNodeUtils.hasSideEffects(insn) || InsnNodeUtils.isIntConstant(insn)) {
+				if (!InsnNodeUtils.isPure(insn) || InsnNodeUtils.isIntConstant(insn)) {
 					continue;
 				}