[cost,inferBo] Add models for Collections.unmodifiable* getters

Reviewed By: ngorogiannis

Differential Revision: D15901108

fbshipit-source-id: fa399412a

infer/src/bufferoverrun/bufferOverrunModels.ml

@@ -817,6 +817,11 @@ module Collection = struct
     {exec; check= check_index ~last_included:false coll_id index_exp}
 end
 
+let unmodifiable _ s =
+  String.is_prefix ~prefix:"unmodifiable" s
+  && List.exists ~f:(fun suffix -> String.is_suffix ~suffix s) ["Set"; "Collection"; "Map"; "List"]
+
+
 module Call = struct
   let dispatch : (Tenv.t, model) ProcnameDispatcher.Call.dispatcher =
     let open ProcnameDispatcher.Call in
@@ -939,6 +944,8 @@ module Call = struct
       ; +PatternMatch.implements_collection
         &:: "<init>" <>$ capt_var_exn $+ capt_exp $--> Collection.init
         (* model sets as lists *)
+      ; +PatternMatch.implements_collections
+        &::+ unmodifiable <>$ capt_exp $--> Collection.iterator
       ; +PatternMatch.implements_collections
         &:: "singleton" <>$ capt_exp $--> Collection.singleton_collection
       ; +PatternMatch.implements_collections

infer/tests/codetoanalyze/java/performance/CollectionsTest.java

@@ -6,6 +6,7 @@
  */
 import java.util.Collections;
 import java.util.List;
+import java.util.Map;
 import java.util.Random;
 import java.util.Set;
 
@@ -46,4 +47,17 @@ class CollectionsTest {
   void copy_linear(List<String> list_from, List<String> list_to) {
     Collections.copy(list_to, list_from);
   }
+
+  void unmodifiable_linear(List<String> list) {
+    List<String> unmod_list = Collections.unmodifiableList(list);
+    for (int i = 0; i < unmod_list.size(); i++) {}
+  }
+
+  void unmodifiable_map(Map<String, String> map) {
+    for (Map.Entry<String, String> entry : Collections.unmodifiableMap(map).entrySet()) {}
+  }
+
+  void unmodifiable_set(Set<Integer> set) {
+    for (Integer el : Collections.unmodifiableSet(set)) {}
+  }
 }

infer/tests/codetoanalyze/java/performance/issues.exp

@@ -67,6 +67,9 @@ codetoanalyze/java/performance/CollectionsTest.java, CollectionsTest.reverse_lin
 codetoanalyze/java/performance/CollectionsTest.java, CollectionsTest.shuffle_linear(java.util.List,java.util.Random):void, 1, EXPENSIVE_EXECUTION_TIME, no_bucket, ERROR, [with estimated cost 3 + list.length, degree = 1,{list.length},Modeled call to Collections.shuffle]
 codetoanalyze/java/performance/CollectionsTest.java, CollectionsTest.singletonList_constant(java.lang.String):void, 2, CONDITION_ALWAYS_FALSE, no_bucket, WARNING, [Here]
 codetoanalyze/java/performance/CollectionsTest.java, CollectionsTest.singletonSet_constant():void, 2, CONDITION_ALWAYS_FALSE, no_bucket, WARNING, [Here]
+codetoanalyze/java/performance/CollectionsTest.java, CollectionsTest.unmodifiable_linear(java.util.List):void, 2, EXPENSIVE_EXECUTION_TIME, no_bucket, ERROR, [with estimated cost 5 + 5 ⋅ list.length + 3 ⋅ (list.length + 1), degree = 1,{list.length + 1},Loop at line 53,{list.length},Loop at line 53]
+codetoanalyze/java/performance/CollectionsTest.java, CollectionsTest.unmodifiable_map(java.util.Map):void, 1, EXPENSIVE_EXECUTION_TIME, no_bucket, ERROR, [with estimated cost 10 + 8 ⋅ (map.length - 1) + 3 ⋅ map.length, degree = 1,{map.length},Loop at line 57,{map.length - 1},Loop at line 57]
+codetoanalyze/java/performance/CollectionsTest.java, CollectionsTest.unmodifiable_set(java.util.Set):void, 1, EXPENSIVE_EXECUTION_TIME, no_bucket, ERROR, [with estimated cost 7 + 8 ⋅ (set.length - 1) + 3 ⋅ set.length, degree = 1,{set.length},Loop at line 61,{set.length - 1},Loop at line 61]
 codetoanalyze/java/performance/Compound_loop.java, codetoanalyze.java.performance.Compound_loop.compound_while(int):int, 3, CONDITION_ALWAYS_TRUE, no_bucket, WARNING, [Here]
 codetoanalyze/java/performance/Compound_loop.java, codetoanalyze.java.performance.Compound_loop.compound_while(int):int, 3, EXPENSIVE_EXECUTION_TIME, no_bucket, ERROR, [with estimated cost 4 + 5 ⋅ m + 2 ⋅ (1+max(0, m)), degree = 1,{1+max(0, m)},Loop at line 15,{m},Loop at line 15]
 codetoanalyze/java/performance/Compound_loop.java, codetoanalyze.java.performance.Compound_loop.nested_while_and_or(int):int, 3, CONDITION_ALWAYS_TRUE, no_bucket, WARNING, [Here]