[FIR] Add attributes for @Exact and @NoInfer

compiler/fir/cones/src/org/jetbrains/kotlin/fir/types/CompilerConeAttributes.kt

@@ -0,0 +1,29 @@
+/*
+ * Copyright 2010-2020 JetBrains s.r.o. and Kotlin Programming Language contributors.
+ * Use of this source code is governed by the Apache 2.0 license that can be found in the license/LICENSE.txt file.
+ */
+
+package org.jetbrains.kotlin.fir.types
+
+import kotlin.reflect.KClass
+
+object CompilerConeAttributes {
+    object Exact : ConeAttribute<Exact>() {
+        override fun union(other: Exact?): Exact? = null
+        override fun intersect(other: Exact?): Exact? = null
+        override fun isSubtypeOf(other: Exact?): Boolean = true
+
+        override val key: KClass<out Exact> = Exact::class
+    }
+
+    object NoInfer : ConeAttribute<NoInfer>() {
+        override fun union(other: NoInfer?): NoInfer? = null
+        override fun intersect(other: NoInfer?): NoInfer? = null
+        override fun isSubtypeOf(other: NoInfer?): Boolean = true
+
+        override val key: KClass<out NoInfer> = NoInfer::class
+    }
+}
+
+val ConeAttributes.exact: CompilerConeAttributes.Exact? by ConeAttributes.attributeAccessor<CompilerConeAttributes.Exact>()
+val ConeAttributes.noInfer: CompilerConeAttributes.NoInfer? by ConeAttributes.attributeAccessor<CompilerConeAttributes.NoInfer>()

compiler/fir/resolve/src/org/jetbrains/kotlin/fir/types/ConeInferenceContext.kt

@@ -251,11 +251,13 @@ interface ConeInferenceContext : TypeSystemInferenceExtensionContext, ConeTypeCo
     }
 
     override fun KotlinTypeMarker.hasExactAnnotation(): Boolean {
-        return false // TODO
+        require(this is ConeKotlinType)
+        return attributes.exact != null
     }
 
     override fun KotlinTypeMarker.hasNoInferAnnotation(): Boolean {
-        return false // TODO
+        require(this is ConeKotlinType)
+        return attributes.noInfer != null
     }
 
     override fun TypeVariableMarker.freshTypeConstructor(): TypeConstructorMarker {