[Wasm] Implement Any::hashCode()

compiler/ir/backend.wasm/src/org/jetbrains/kotlin/backend/wasm/ir2wasm/BodyGenerator.kt

@@ -267,6 +267,7 @@ class BodyGenerator(val context: WasmFunctionCodegenContext) : IrElementVisitorV
             val klassId = context.referenceClassId(klass.symbol)
 
             body.buildConstI32Symbol(klassId)
+            body.buildConstI32(0) // Any::_hashCode
             generateExpression(call.getValueArgument(0)!!)
             body.buildGetGlobal(context.referenceClassRTT(klass.symbol))
             body.buildStructNew(structTypeName)

libraries/stdlib/wasm/builtins/kotlin/Any.kt

@@ -7,6 +7,8 @@ package kotlin
 
 import kotlin.wasm.internal.*
 
+import kotlin.random.*
+
 /**
  * The root of the Kotlin class hierarchy. Every Kotlin class has [Any] as a superclass.
  */
@@ -37,8 +39,12 @@ public open class Any {
      * * Whenever it is invoked on the same object more than once, the `hashCode` method must consistently return the same integer, provided no information used in `equals` comparisons on the object is modified.
      * * If two objects are equal according to the `equals()` method, then calling the `hashCode` method on each of the two objects must produce the same integer result.
      */
-    // TODO: Implement
-    public open fun hashCode(): Int = 100
+    internal var _hashCode: Int = 0
+    public open fun hashCode(): Int {
+        if (_hashCode == 0)
+            _hashCode = Random.nextInt(1, Int.MAX_VALUE)
+        return _hashCode
+    }
 
     /**
      * Returns a string representation of the object.

libraries/stdlib/wasm/builtins/kotlin/String.kt

@@ -59,15 +59,14 @@ public class String private constructor(internal val chars: CharArray) : Compara
 
     public override fun toString(): String = this
 
-    private var cachedHash: Int = 0
     public override fun hashCode(): Int {
-        if (cachedHash != 0 || this.isEmpty())
-            return cachedHash
+        if (_hashCode != 0 || this.isEmpty())
+            return _hashCode
         var hash = 0
         for (c in chars)
             hash = 31 * hash + c.toInt()
-        cachedHash = hash
-        return cachedHash
+        _hashCode = hash
+        return _hashCode
     }
 }