Add new compiler errors and flags when JVM compiles against JVM IR

From now on, the old JVM backend will report an error by default when
compiling against class files produced by the JVM IR backend. This is
needed because we're not yet sure that the ABI generated by JVM IR is
fully correct and do not want to land in a 2-dimensional compatibility
situation where we'll need to consider twice more scenarios when
introducing any breaking change in the language. This is generally OK
since the JVM IR backend is still going to be experimental in 1.4.

However, for purposes of users which _do_ need to compile something with
the old backend against JVM IR, we provide two new compiler flags:
* -Xallow-jvm-ir-dependencies -- allows to suppress the error when
  compiling with the old backend against JVM IR.
* -Xir-binary-with-stable-api -- allows to mark the generated binaries
  as stable, when compiling anything with JVM IR, so that dependent
  modules will compile even with the old backend automatically. In this
  case, the author usually does not care for the generated ABI, or s/he
  ensures that it's consistent with the one expected by the old compiler
  with some external tools.

Internally, this is implemented by storing two new flags in
kotlin.Metadata: one tells if the class file was compiled with the JVM
IR, and another tells if the class file is stable (in case it's compiled
with JVM IR). Implementation is similar to the diagnostic reported by
the pre-release dependency checker.

core/descriptors.jvm/src/org/jetbrains/kotlin/load/java/JvmAnnotationNames.java

@@ -39,6 +39,8 @@ public final class JvmAnnotationNames {
     public static final int METADATA_PRE_RELEASE_FLAG = 1 << 1;
     public static final int METADATA_SCRIPT_FLAG = 1 << 2;
     public static final int METADATA_STRICT_VERSION_SEMANTICS_FLAG = 1 << 3;
+    public static final int METADATA_JVM_IR_FLAG = 1 << 4;
+    public static final int METADATA_JVM_IR_STABLE_ABI_FLAG = 1 << 5;
 
     public static final Name DEFAULT_ANNOTATION_MEMBER_NAME = Name.identifier("value");
 

core/descriptors.jvm/src/org/jetbrains/kotlin/load/kotlin/DeserializedDescriptorResolver.kt

@@ -52,7 +52,9 @@ class DeserializedDescriptorResolver {
         val (nameResolver, classProto) = parseProto(kotlinClass) {
             JvmProtoBufUtil.readClassDataFrom(data, strings)
         } ?: return null
-        val source = KotlinJvmBinarySourceElement(kotlinClass, kotlinClass.incompatibility, kotlinClass.isPreReleaseInvisible)
+        val source = KotlinJvmBinarySourceElement(
+            kotlinClass, kotlinClass.incompatibility, kotlinClass.isPreReleaseInvisible, kotlinClass.isInvisibleJvmIrDependency
+        )
         return ClassData(nameResolver, classProto, kotlinClass.classHeader.metadataVersion, source)
     }
 
@@ -63,7 +65,8 @@ class DeserializedDescriptorResolver {
             JvmProtoBufUtil.readPackageDataFrom(data, strings)
         } ?: return null
         val source = JvmPackagePartSource(
-            kotlinClass, packageProto, nameResolver, kotlinClass.incompatibility, kotlinClass.isPreReleaseInvisible
+            kotlinClass, packageProto, nameResolver, kotlinClass.incompatibility, kotlinClass.isPreReleaseInvisible,
+            kotlinClass.isInvisibleJvmIrDependency
         )
         return DeserializedPackageMemberScope(
             descriptor, packageProto, nameResolver, kotlinClass.classHeader.metadataVersion, source, components
@@ -94,6 +97,9 @@ class DeserializedDescriptorResolver {
         get() = !components.configuration.skipMetadataVersionCheck &&
                 classHeader.isPreRelease && classHeader.metadataVersion == KOTLIN_1_3_M1_METADATA_VERSION
 
+    private val KotlinJvmBinaryClass.isInvisibleJvmIrDependency: Boolean
+        get() = components.configuration.reportErrorsOnIrDependencies && classHeader.isUnstableJvmIrBinary
+
     private fun readData(kotlinClass: KotlinJvmBinaryClass, expectedKinds: Set<KotlinClassHeader.Kind>): Array<String>? {
         val header = kotlinClass.classHeader
         return (header.data ?: header.incompatibleData)?.takeIf { header.kind in expectedKinds }

core/descriptors.jvm/src/org/jetbrains/kotlin/load/kotlin/JvmPackagePartSource.kt

@@ -36,6 +36,7 @@ class JvmPackagePartSource(
     nameResolver: NameResolver,
     override val incompatibility: IncompatibleVersionErrorData<JvmMetadataVersion>? = null,
     override val isPreReleaseInvisible: Boolean = false,
+    override val isInvisibleIrDependency: Boolean = false,
     val knownJvmBinaryClass: KotlinJvmBinaryClass? = null
 ) : DeserializedContainerSource {
     constructor(
@@ -43,7 +44,8 @@ class JvmPackagePartSource(
         packageProto: ProtoBuf.Package,
         nameResolver: NameResolver,
         incompatibility: IncompatibleVersionErrorData<JvmMetadataVersion>? = null,
-        isPreReleaseInvisible: Boolean = false
+        isPreReleaseInvisible: Boolean = false,
+        isInvisibleIrDependency: Boolean = false
     ) : this(
         JvmClassName.byClassId(kotlinClass.classId),
         kotlinClass.classHeader.multifileClassName?.let {
@@ -53,6 +55,7 @@ class JvmPackagePartSource(
         nameResolver,
         incompatibility,
         isPreReleaseInvisible,
+        isInvisibleIrDependency,
         kotlinClass
     )
 

core/descriptors.jvm/src/org/jetbrains/kotlin/load/kotlin/KotlinJvmBinarySourceElement.kt

@@ -24,7 +24,8 @@ import org.jetbrains.kotlin.serialization.deserialization.descriptors.Deserializ
 class KotlinJvmBinarySourceElement(
     val binaryClass: KotlinJvmBinaryClass,
     override val incompatibility: IncompatibleVersionErrorData<JvmMetadataVersion>? = null,
-    override val isPreReleaseInvisible: Boolean = false
+    override val isPreReleaseInvisible: Boolean = false,
+    override val isInvisibleIrDependency: Boolean = false
 ) : DeserializedContainerSource {
     override val presentableString: String
         get() = "Class '${binaryClass.classId.asSingleFqName().asString()}'"

core/descriptors.jvm/src/org/jetbrains/kotlin/load/kotlin/header/KotlinClassHeader.kt

@@ -71,6 +71,10 @@ class KotlinClassHeader(
                 DELEGATING
         } else null
 
+    val isUnstableJvmIrBinary: Boolean
+        get() = (extraInt and JvmAnnotationNames.METADATA_JVM_IR_FLAG) != 0 &&
+                (extraInt and JvmAnnotationNames.METADATA_JVM_IR_STABLE_ABI_FLAG == 0)
+
     val isPreRelease: Boolean
         get() = (extraInt and JvmAnnotationNames.METADATA_PRE_RELEASE_FLAG) != 0
 

core/deserialization/src/org/jetbrains/kotlin/serialization/deserialization/DeserializationConfiguration.kt

@@ -12,6 +12,9 @@ interface DeserializationConfiguration {
     val reportErrorsOnPreReleaseDependencies: Boolean
         get() = false
 
+    val reportErrorsOnIrDependencies: Boolean
+        get() = false
+
     val typeAliasesAllowed: Boolean
         get() = true
 

core/deserialization/src/org/jetbrains/kotlin/serialization/deserialization/descriptors/DeserializedMemberDescriptor.kt

@@ -52,6 +52,10 @@ interface DeserializedContainerSource : SourceElement {
     // True iff this is container is "invisible" because it's loaded from a pre-release class and this compiler is a release
     val isPreReleaseInvisible: Boolean
 
+    // True iff this container was compiled by the new IR backend, this compiler is not using the IR backend right now,
+    // and no additional flags to override this behavior were specified.
+    val isInvisibleIrDependency: Boolean
+
     // This string should only be used in error messages
     val presentableString: String
 }