[cost] Add mli file for CostDomain

Reviewed By: jvillard

Differential Revision: D19471030

fbshipit-source-id: bdf4876b8

infer/src/checkers/costDomain.ml

@@ -52,7 +52,6 @@ let get_operation_cost cost_record = get_cost_kind CostKind.OperationCost cost_r
 
 let map ~f cost_record = VariantCostMap.map f cost_record
 
-(* Map representing cost record {OperationCost:0; AllocationCost:0; IOCost:0} *)
 let zero_record = VariantCostMap.empty
 
 let mult_by_scalar cost_record scalar = map cost_record ~f:(BasicCost.mult scalar)
@@ -63,12 +62,9 @@ let plus cost_record1 cost_record2 =
     cost_record1 cost_record2
 
 
-(* Map representing cost record {OperationCost:1; AllocationCost:0; IOCost:0} *)
 let unit_cost_atomic_operation = VariantCostMap.increment CostKind.OperationCost zero_record
 
-(* Map representing cost record {OperationCost:0; AllocationCost:1; IOCost:0} *)
 let unit_cost_allocation = VariantCostMap.increment CostKind.AllocationCost zero_record
 
-(* Map representing cost record {OperationCost:operation_cost; AllocationCost:0; IOCost:0} *)
 let of_operation_cost operation_cost =
   VariantCostMap.increase_by CostKind.OperationCost operation_cost zero_record

infer/src/checkers/costDomain.mli

@@ -0,0 +1,54 @@
+(*
+ * Copyright (c) Facebook, Inc. and its affiliates.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ *)
+
+open! IStd
+module F = Format
+
+module BasicCost : sig
+  include
+    module type of Polynomials.NonNegativePolynomial
+      with type t = Polynomials.NonNegativePolynomial.t
+
+  val version : int
+  (** version used to consistently compare at infer-reportdiff phase *)
+end
+
+module VariantCostMap : sig
+  type t = BasicCost.t CostIssues.CostKindMap.t
+
+  val pp : F.formatter -> t -> unit
+end
+
+type t = VariantCostMap.t
+
+type summary = {post: t; is_on_ui_thread: bool}
+
+val pp_summary : F.formatter -> summary -> unit
+
+val get_cost_kind : CostKind.t -> t -> BasicCost.t
+
+val get_operation_cost : t -> BasicCost.t
+
+val map : f:(BasicCost.t -> BasicCost.t) -> t -> t
+
+val zero_record : t
+(** Map representing cost record {OperationCost:0; AllocationCost:0; IOCost:0} *)
+
+val mult_by_scalar : t -> BasicCost.t -> t
+(** Map where each element is multiplied by a cost *)
+
+val plus : t -> t -> t
+(** Union of two maps where common costs are added together *)
+
+val unit_cost_atomic_operation : t
+(** Map representing cost record {OperationCost:1; AllocationCost:0; IOCost:0} *)
+
+val unit_cost_allocation : t
+(** Map representing cost record {OperationCost:0; AllocationCost:1; IOCost:0} *)
+
+val of_operation_cost : BasicCost.t -> t
+(** Map representing cost record {OperationCost:operation_cost; AllocationCost:0; IOCost:0} *)