FIR: Use intersection of all upper bounds for parameterized types in

ConeKotlinType.canBeNull.

^KT-45903 In progress

compiler/testData/codegen/box/javaInterop/notNullAssertions/typeParameterWithMixedNullableAndNotNullableBounds.kt

@@ -0,0 +1,26 @@
+// TARGET_BACKEND: JVM
+// IGNORE_BACKEND: JVM, JVM_IR
+
+// Note: This fails on non-FIR because of KT-45903 (missing not-null assertion on argument).
+
+// FILE: typeParameterWithMixedNullableAndNotNullableBounds.kt
+fun <T> f(x: T): Int where T : CharSequence?, T : Comparable<T> {
+    try {
+        return x.compareTo(x)
+    } catch (e: NullPointerException) {
+        return 42
+    }
+}
+
+fun box() = try {
+    val r = f(J.s())
+    if (r == 42) "FAIL" else "Unexpected, x.compareTo(x) should have NPE'd"
+} catch (e: NullPointerException) {
+    "OK"
+}
+
+
+// FILE: J.java
+public class J {
+    public static String s() { return null; }
+}

compiler/testData/codegen/box/javaInterop/notNullAssertions/typeParameterWithMultipleNotNullableBounds.kt

@@ -0,0 +1,22 @@
+// TARGET_BACKEND: JVM
+// FILE: typeParameterWithMultipleNotNullableBounds.kt
+fun <T> f(x: T): Int where T : CharSequence, T : Comparable<T> {
+    try {
+        return x.compareTo(x)
+    } catch (e: NullPointerException) {
+        return 42
+    }
+}
+
+fun box() = try {
+    val r = f(J.s())
+    if (r == 42) "FAIL" else "Unexpected, x.compareTo(x) should have NPE'd"
+} catch (e: NullPointerException) {
+    "OK"
+}
+
+
+// FILE: J.java
+public class J {
+    public static String s() { return null; }
+}

compiler/testData/codegen/box/javaInterop/notNullAssertions/typeParameterWithMultipleNullableBounds.kt

@@ -0,0 +1,12 @@
+// TARGET_BACKEND: JVM
+// FILE: typeParameterWithMultipleNullableBounds.kt
+fun <T> f(x: T): Int? where T : CharSequence?, T : Comparable<T>? {
+    return x?.compareTo(x)
+}
+
+fun box() = f(J.s()) ?: "OK"
+
+// FILE: J.java
+public class J {
+    public static String s() { return null; }
+}