[K/N] Fix cast to NativePtr mis-compilation

^KT-59022

compiler/testData/codegen/box/casts/toNativePointers.kt

@@ -0,0 +1,32 @@
+// TARGET_BACKEND: NATIVE
+
+@file:OptIn(kotlinx.cinterop.ExperimentalForeignApi::class)
+
+import kotlinx.cinterop.*
+
+fun getNp() : NativePtr? = null
+fun getOp() : COpaquePointer? = null
+
+fun box() : String {
+    if ((null as NativePtr?) != null) return "FAIL 1.1"
+    if ((null as? NativePtr) != null) return "FAIL 1.2"
+    if (null !is NativePtr?) return "FAIL 1.3"
+    if (null is NativePtr) return "FAIL 1.4"
+
+    if ((null as COpaquePointer?) != null) return "FAIL 2.1"
+    if ((null as? COpaquePointer) != null) return "FAIL 2.2"
+    if (null !is COpaquePointer?) return "FAIL 2.3"
+    if (null is COpaquePointer) return "FAIL 2.4"
+
+    if ((getNp() as NativePtr?) != null) return "FAIL 3.1"
+    if ((getNp() as? NativePtr) != null) return "FAIL 3.2"
+    if (getNp() !is NativePtr?) return "FAIL 3.3"
+    if (getNp() is NativePtr) return "FAIL 3.4"
+
+    if ((getOp() as COpaquePointer?) != null) return "FAIL 4.1"
+    if ((getOp() as? COpaquePointer) != null) return "FAIL 4.2"
+    if (getOp() !is COpaquePointer?) return "FAIL 4.3"
+    if (getOp() is COpaquePointer) return "FAIL 4.4"
+
+    return "OK"
+}

kotlin-native/backend.native/compiler/ir/backend.native/src/org/jetbrains/kotlin/backend/konan/llvm/IrToBitcode.kt

@@ -1628,7 +1628,8 @@ internal class CodeGeneratorVisitor(
                 positionAtEnd(bbExit)
                 appendingTo(resultInstanceOfBB) { br(bbExit) }
                 appendingTo(resultNullBB) { br(bbExit) }
-                val result = phi(value.type.toLLVMType(llvm))
+                require(resultNull.type == resultInstanceOf.type)
+                val result = phi(resultNull.type)
                 addPhiIncoming(result, resultNullBB to resultNull, resultInstanceOfBB to resultInstanceOf)
                 result
             }

native/native.tests/tests-gen/org/jetbrains/kotlin/konan/blackboxtest/FirNativeCodegenBoxTestGenerated.java

@@ -3682,6 +3682,12 @@ public class FirNativeCodegenBoxTestGenerated extends AbstractNativeCodegenBoxTe
                 runTest("compiler/testData/codegen/box/casts/objectToPrimitiveWithAssertion.kt");
             }
 
+            @Test
+            @TestMetadata("toNativePointers.kt")
+            public void testToNativePointers() throws Exception {
+                runTest("compiler/testData/codegen/box/casts/toNativePointers.kt");
+            }
+
             @Test
             @TestMetadata("unitAsAny.kt")
             public void testUnitAsAny() throws Exception {

native/native.tests/tests-gen/org/jetbrains/kotlin/konan/blackboxtest/FirNativeCodegenBoxTestNoPLGenerated.java

@@ -3760,6 +3760,12 @@ public class FirNativeCodegenBoxTestNoPLGenerated extends AbstractNativeCodegenB
                 runTest("compiler/testData/codegen/box/casts/objectToPrimitiveWithAssertion.kt");
             }
 
+            @Test
+            @TestMetadata("toNativePointers.kt")
+            public void testToNativePointers() throws Exception {
+                runTest("compiler/testData/codegen/box/casts/toNativePointers.kt");
+            }
+
             @Test
             @TestMetadata("unitAsAny.kt")
             public void testUnitAsAny() throws Exception {

native/native.tests/tests-gen/org/jetbrains/kotlin/konan/blackboxtest/NativeCodegenBoxTestGenerated.java

@@ -3644,6 +3644,12 @@ public class NativeCodegenBoxTestGenerated extends AbstractNativeCodegenBoxTest
                 runTest("compiler/testData/codegen/box/casts/objectToPrimitiveWithAssertion.kt");
             }
 
+            @Test
+            @TestMetadata("toNativePointers.kt")
+            public void testToNativePointers() throws Exception {
+                runTest("compiler/testData/codegen/box/casts/toNativePointers.kt");
+            }
+
             @Test
             @TestMetadata("unitAsAny.kt")
             public void testUnitAsAny() throws Exception {

native/native.tests/tests-gen/org/jetbrains/kotlin/konan/blackboxtest/NativeCodegenBoxTestNoPLGenerated.java

@@ -3683,6 +3683,12 @@ public class NativeCodegenBoxTestNoPLGenerated extends AbstractNativeCodegenBoxT
                 runTest("compiler/testData/codegen/box/casts/objectToPrimitiveWithAssertion.kt");
             }
 
+            @Test
+            @TestMetadata("toNativePointers.kt")
+            public void testToNativePointers() throws Exception {
+                runTest("compiler/testData/codegen/box/casts/toNativePointers.kt");
+            }
+
             @Test
             @TestMetadata("unitAsAny.kt")
             public void testUnitAsAny() throws Exception {