[hoisting] Hoist only expensive pure functions

Reviewed By: mbouaziz

Differential Revision: D10236706

fbshipit-source-id: c51a9ff0c

Makefile

@@ -92,7 +92,7 @@ BUILD_SYSTEMS_TESTS += \
 
 DIRECT_TESTS += \
   java_checkers java_eradicate java_infer java_lab java_tracing java_quandary \
-  java_racerd java_stability java_crashcontext java_hoisting java_starvation java_performance java_purity
+  java_racerd java_stability java_crashcontext java_hoisting java_hoistingExpensive java_starvation java_performance java_purity
 ifneq ($(ANT),no)
 BUILD_SYSTEMS_TESTS += ant
 endif

infer/man/man1/infer-full.txt

@@ -412,6 +412,11 @@ OPTIONS
            infer-diff(1), infer-events(1), infer-explore(1), infer-report(1),
            infer-reportdiff(1), and infer-run(1).
 
+       --hoisting-report-only-expensive
+           Activates: [Hoisting] Report loop-invariant calls only when the
+           function is expensive, i.e. at least linear (Conversely:
+           --no-hoisting-report-only-expensive)           See also infer-report(1).
+
        --html
            Activates: Generate html report. (Conversely: --no-html)       
     See also infer-explore(1).

infer/man/man1/infer-report.txt

@@ -161,6 +161,11 @@ OPTIONS
            Activates: Whether paths in --skip-analysis-in-path should be
            compiled or not (Conversely:
            --no-skip-analysis-in-path-skips-compilation)
+HOISTING OPTIONS
+       --hoisting-report-only-expensive
+           Activates: [Hoisting] Report loop-invariant calls only when the
+           function is expensive, i.e. at least linear (Conversely:
+           --no-hoisting-report-only-expensive)
 
 
 ENVIRONMENT

infer/man/man1/infer.txt

@@ -412,6 +412,11 @@ OPTIONS
            infer-diff(1), infer-events(1), infer-explore(1), infer-report(1),
            infer-reportdiff(1), and infer-run(1).
 
+       --hoisting-report-only-expensive
+           Activates: [Hoisting] Report loop-invariant calls only when the
+           function is expensive, i.e. at least linear (Conversely:
+           --no-hoisting-report-only-expensive)           See also infer-report(1).
+
        --html
            Activates: Generate html report. (Conversely: --no-html)       
     See also infer-explore(1).

infer/src/base/Config.ml

@@ -208,6 +208,8 @@ let manual_crashcontext = "CRASHCONTEXT OPTIONS"
 
 let manual_generic = Cmdliner.Manpage.s_options
 
+let manual_hoisting = "HOISTING OPTIONS"
+
 let manual_internal = "INTERNAL OPTIONS"
 
 let manual_java = "JAVA OPTIONS"
@@ -1376,6 +1378,13 @@ and html =
     "Generate html report."
 
 
+and hoisting_report_only_expensive =
+  CLOpt.mk_bool ~long:"hoisting-report-only-expensive" ~default:false
+    ~in_help:InferCommand.[(Report, manual_hoisting)]
+    "[Hoisting] Report loop-invariant calls only when the function is expensive, i.e. at least \
+     linear"
+
+
 and icfg_dotty_outfile =
   CLOpt.mk_path_opt ~long:"icfg-dotty-outfile" ~meta:"path"
     "If set, specifies path where .dot file should be written, it overrides the path for all \
@@ -2612,6 +2621,8 @@ and get_linter_doc_url = process_linters_doc_url !linters_doc_url
 
 and html = !html
 
+and hoisting_report_only_expensive = !hoisting_report_only_expensive
+
 and icfg_dotty_outfile = !icfg_dotty_outfile
 
 and ignore_trivial_traces = !ignore_trivial_traces

infer/src/base/Config.mli

@@ -380,6 +380,8 @@ val get_linter_doc_url : linter_id:string -> string option
 
 val html : bool
 
+val hoisting_report_only_expensive : bool
+
 val icfg_dotty_outfile : string option
 
 val ignore_trivial_traces : bool

infer/src/bufferoverrun/bufferOverrunChecker.ml

@@ -243,6 +243,18 @@ module Analyzer = AbstractInterpreter.MakeRPO (TransferFunctions (CFG))
 
 type invariant_map = Analyzer.invariant_map
 
+(* Use a weak Hashtbl to prevent memory leaks (GC unnecessarily
+   keeping invariant maps around) *)
+module WeakInvMapHashTbl = Caml.Weak.Make (struct
+  type t = Typ.Procname.t * invariant_map option
+
+  let equal (pname1, _) (pname2, _) = Typ.Procname.equal pname1 pname2
+
+  let hash (pname, _) = Hashtbl.hash pname
+end)
+
+let inv_map_cache = WeakInvMapHashTbl.create 100
+
 module Init = struct
   let declare_symbolic_val :
          Typ.Procname.t
@@ -749,8 +761,28 @@ let compute_invariant_map_and_check : Callbacks.proc_callback_args -> invariant_
     | _ ->
         summary
   in
+  if Config.hoisting_report_only_expensive then
+    let pname = Procdesc.get_proc_name proc_desc in
+    WeakInvMapHashTbl.add inv_map_cache (pname, Some inv_map)
+  else () ;
   (inv_map, summary)
 
 
+let lookup_inv_map_cache (callback_args : Callbacks.proc_callback_args) (pname : Typ.Procname.t) :
+    invariant_map =
+  (* Since we are using a weak Hashtbl, represented as a set of
+     (Procname) hashed values, we have to lookup with a dummy element
+     *)
+  match WeakInvMapHashTbl.find_opt inv_map_cache (pname, None) with
+  | Some (_, Some inv_map) ->
+      inv_map
+  | Some (_, None) ->
+      (* this should never happen *)
+      assert false
+  | None ->
+      (* if bufferoverrun has not been run yet, run it *)
+      compute_invariant_map_and_check callback_args |> fst
+
+
 let checker : Callbacks.proc_callback_args -> Summary.t =
  fun args -> compute_invariant_map_and_check args |> snd

infer/src/bufferoverrun/bufferOverrunChecker.mli

@@ -15,6 +15,8 @@ module CFG = ProcCfg.NormalOneInstrPerNode
 
 type invariant_map
 
+val lookup_inv_map_cache : Callbacks.proc_callback_args -> Typ.Procname.t -> invariant_map
+
 val compute_invariant_map_and_check : Callbacks.proc_callback_args -> invariant_map * Summary.t
 
 val extract_pre : CFG.Node.id -> invariant_map -> BufferOverrunDomain.Mem.t option

infer/src/checkers/cost.ml

@@ -33,13 +33,6 @@ module Node = ProcCfg.DefaultNode
    set it to 1 and for function call we take it from the spec of the function.
    The nodes in the domain of the map are those in the path reaching the current node.
 *)
-module TransferFunctionsNodesBasicCost = struct
-  module CFG = InstrCFG
-  module Domain = NodesBasicCostDomain
-
-  type extras = BufferOverrunChecker.invariant_map
-
-  let cost_atomic_instruction = BasicCost.one
 
 let instantiate_cost ~caller_pdesc ~inferbo_caller_mem ~callee_pname ~params ~callee_cost =
   match Ondemand.get_proc_desc callee_pname with
@@ -55,12 +48,18 @@ module TransferFunctionsNodesBasicCost = struct
           callee_cost Typ.Procname.pp callee_pname
     | Some _ ->
         let inferbo_caller_mem = Option.value_exn inferbo_caller_mem in
-          let eval_sym =
+        let eval_sym = BufferOverrunSemantics.mk_eval_sym callee_pdesc params inferbo_caller_mem in
-            BufferOverrunSemantics.mk_eval_sym callee_pdesc params inferbo_caller_mem
-          in
         BasicCost.subst callee_cost eval_sym )
 
 
+module TransferFunctionsNodesBasicCost = struct
+  module CFG = InstrCFG
+  module Domain = NodesBasicCostDomain
+
+  type extras = BufferOverrunChecker.invariant_map
+
+  let cost_atomic_instruction = BasicCost.one
+
   let exec_instr_cost inferbo_mem (astate : CostDomain.NodeInstructionToCostMap.astate)
       {ProcData.pdesc} (node : CFG.Node.t) instr : CostDomain.NodeInstructionToCostMap.astate =
     let key = CFG.Node.id node in

infer/src/checkers/cost.mli

@@ -8,3 +8,11 @@
 open! IStd
 
 val checker : Callbacks.proc_callback_t
+
+val instantiate_cost :
+     caller_pdesc:Procdesc.t
+  -> inferbo_caller_mem:BufferOverrunDomain.Mem.astate option
+  -> callee_pname:Typ.Procname.t
+  -> params:(Exp.t * 'a) list
+  -> callee_cost:Itv.NonNegativePolynomial.astate
+  -> Itv.NonNegativePolynomial.astate

infer/src/checkers/hoisting.ml

@@ -9,7 +9,9 @@ module F = Format
 module InstrCFG = ProcCfg.NormalOneInstrPerNode
 
 module Call = struct
-  type t = {pname: Typ.Procname.t; loc: Location.t} [@@deriving compare]
+  type t =
+    {loc: Location.t; pname: Typ.Procname.t; node: Procdesc.Node.t; params: (Exp.t * Typ.t) list}
+  [@@deriving compare]
 
   let pp fmt {pname; loc} =
     F.fprintf fmt "loop-invariant call to %a, at %a " Typ.Procname.pp pname Location.pp loc
@@ -28,12 +30,12 @@ module LoopHeadToHoistInstrs = Procdesc.NodeMap
 
 let add_if_hoistable inv_vars instr node source_nodes idom hoistable_calls =
   match instr with
-  | Sil.Call ((ret_id, _), Exp.Const (Const.Cfun pname), _, loc, _)
+  | Sil.Call ((ret_id, _), Exp.Const (Const.Cfun pname), params, loc, _)
     when (* Check condition (1); N dominates all loop sources *)
          List.for_all ~f:(fun source -> Dominators.dominates idom node source) source_nodes
          && (* Check condition (2); id should be invariant already *)
             LoopInvariant.InvariantVars.mem (Var.of_id ret_id) inv_vars ->
-      HoistCalls.add {pname; loc} hoistable_calls
+      HoistCalls.add {pname; loc; node; params} hoistable_calls
   | _ ->
       hoistable_calls
 
@@ -73,7 +75,25 @@ let do_report summary Call.({pname; loc}) loop_head_loc =
   Reporting.log_error summary ~loc ~ltr IssueType.invariant_call message
 
 
-let checker {Callbacks.tenv; summary; proc_desc} : Summary.t =
+let should_report proc_desc Call.({pname; node; params}) inferbo_invariant_map =
+  (not Config.hoisting_report_only_expensive)
+  ||
+  (* only report if function call has expensive/symbolic cost *)
+  match Ondemand.analyze_proc_name pname with
+  | Some {Summary.payloads= {Payloads.cost= Some {CostDomain.post= cost}}}
+    when Itv.NonNegativePolynomial.is_symbolic cost ->
+      let instr_node_id = InstrCFG.last_of_underlying_node node |> InstrCFG.Node.id in
+      let inferbo_invariant_map = Lazy.force inferbo_invariant_map in
+      let inferbo_mem = BufferOverrunChecker.extract_pre instr_node_id inferbo_invariant_map in
+      (* get the cost of the function call *)
+      Cost.instantiate_cost ~caller_pdesc:proc_desc ~inferbo_caller_mem:inferbo_mem
+        ~callee_pname:pname ~params ~callee_cost:cost
+      |> Itv.NonNegativePolynomial.is_symbolic
+  | _ ->
+      false
+
+
+let checker ({Callbacks.tenv; summary; proc_desc} as callback_args) : Summary.t =
   let cfg = InstrCFG.from_pdesc proc_desc in
   let proc_data = ProcData.make_default proc_desc tenv in
   (* computes reaching defs: node -> (var -> node set) *)
@@ -81,6 +101,10 @@ let checker {Callbacks.tenv; summary; proc_desc} : Summary.t =
     ReachingDefs.Analyzer.exec_cfg cfg proc_data
       ~initial:(ReachingDefs.init_reaching_defs_with_formals proc_desc)
   in
+  let pname = Procdesc.get_proc_name proc_desc in
+  let inferbo_invariant_map =
+    lazy (BufferOverrunChecker.lookup_inv_map_cache callback_args pname)
+  in
   (* get dominators *)
   let idom = Dominators.get_idoms proc_desc in
   let loop_head_to_source_nodes = Loop_control.get_loop_head_to_source_nodes cfg in
@@ -94,6 +118,10 @@ let checker {Callbacks.tenv; summary; proc_desc} : Summary.t =
   LoopHeadToHoistInstrs.iter
     (fun loop_head inv_instrs ->
       let loop_head_loc = Procdesc.Node.get_loc loop_head in
-      HoistCalls.iter (fun call -> do_report summary call loop_head_loc) inv_instrs )
+      HoistCalls.iter
+        (fun call ->
+          if should_report proc_desc call inferbo_invariant_map then
+            do_report summary call loop_head_loc )
+        inv_instrs )
     loop_head_to_inv_instrs ;
   summary

infer/src/checkers/loopInvariant.ml

@@ -27,8 +27,13 @@ let is_fun_call_invariant tenv ~is_exp_invariant ~is_inv_by_default callee_pname
   match Models.Call.dispatch tenv callee_pname params with
   | Some inv ->
       InvariantModels.is_invariant inv
-  | None ->
+  | None -> (
-      is_inv_by_default
+    (* If there is no model, invoke purity analysis to see if function is pure *)
+    match Ondemand.analyze_proc_name callee_pname with
+    | Some {Summary.payloads= {Payloads.purity= Some is_pure}} ->
+        is_pure
+    | _ ->
+        is_inv_by_default )
 
 
 (* check if the def of var is unique and invariant *)

infer/src/checkers/purity.ml

@@ -61,12 +61,12 @@ module TransferFunctions (CFG : ProcCfg.S) = struct
   let pp_session_name _node fmt = F.pp_print_string fmt "purity checker"
 end
 
-module Analyzer = LowerHil.MakeAbstractInterpreter (ProcCfg.Exceptional) (TransferFunctions)
+module Analyzer = LowerHil.MakeAbstractInterpreter (ProcCfg.Normal) (TransferFunctions)
 
-let should_report pure pdesc =
+let should_report is_pure pdesc =
   match Procdesc.get_proc_name pdesc with
   | Typ.Procname.Java java_pname as proc_name ->
-      pure
+      is_pure
       && (not (Typ.Procname.is_constructor proc_name))
       && (not (Typ.Procname.Java.is_class_initializer java_pname))
       && not (Typ.Procname.Java.is_access_method java_pname)
@@ -85,9 +85,9 @@ let checker {Callbacks.tenv; summary; proc_desc} : Summary.t =
     Reporting.log_error summary ~loc ~ltr IssueType.pure_function exp_desc
   in
   match Analyzer.compute_post proc_data ~initial with
-  | Some pure ->
+  | Some is_pure ->
-      if should_report pure proc_desc then report_pure () ;
+      if should_report is_pure proc_desc then report_pure () ;
-      Payload.update_summary pure summary
+      Payload.update_summary is_pure summary
   | None ->
       L.internal_error "Analyzer failed to compute purity information for %a@." Typ.Procname.pp
         proc_name ;

infer/src/checkers/registerCheckers.ml

@@ -109,8 +109,12 @@ let all_checkers =
   ; { name= "loop hoisting"
     ; active= Config.loop_hoisting
     ; callbacks=
-        [(Procedure Hoisting.checker, Language.Clang); (Procedure Hoisting.checker, Language.Java)]
+        [ (Procedure Hoisting.checker, Language.Clang)
-    }
+        ; (Procedure Hoisting.checker, Language.Java)
+        ; (Procedure Cost.checker, Language.Clang)
+        ; (Procedure Cost.checker, Language.Java)
+        ; (Procedure Purity.checker, Language.Clang)
+        ; (Procedure Purity.checker, Language.Java) ] }
   ; { name= "Starvation analysis"
     ; active= Config.starvation
     ; callbacks=

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

@@ -1,12 +1,27 @@
 codetoanalyze/java/hoisting/Hoist.java, Hoist.array_store_hoist(int,int[]):void, 5, INVARIANT_CALL, no_bucket, ERROR, [Loop-invariant call to int Hoist.foo(int,int) at line 117]
+codetoanalyze/java/hoisting/Hoist.java, Hoist.bar(int):int, 0, PURE_FUNCTION, no_bucket, ERROR, [Side-effect free function int Hoist.bar(int)]
+codetoanalyze/java/hoisting/Hoist.java, Hoist.clash_function_calls_hoist(int):void, 0, PURE_FUNCTION, no_bucket, ERROR, [Side-effect free function void Hoist.clash_function_calls_hoist(int)]
 codetoanalyze/java/hoisting/Hoist.java, Hoist.clash_function_calls_hoist(int):void, 4, INVARIANT_CALL, no_bucket, ERROR, [Loop-invariant call to int Hoist.foo(int,int) at line 26]
+codetoanalyze/java/hoisting/Hoist.java, Hoist.dep_not_invariant_dont_hoist(int,int[]):void, 0, PURE_FUNCTION, no_bucket, ERROR, [Side-effect free function void Hoist.dep_not_invariant_dont_hoist(int,int[])]
+codetoanalyze/java/hoisting/Hoist.java, Hoist.dumb_foo():void, 0, PURE_FUNCTION, no_bucket, ERROR, [Side-effect free function void Hoist.dumb_foo()]
+codetoanalyze/java/hoisting/Hoist.java, Hoist.foo(int,int):int, 0, PURE_FUNCTION, no_bucket, ERROR, [Side-effect free function int Hoist.foo(int,int)]
 codetoanalyze/java/hoisting/Hoist.java, Hoist.legit_hoist(int,int[]):void, 5, INVARIANT_CALL, no_bucket, ERROR, [Loop-invariant call to int Hoist.foo(int,int) at line 73]
+codetoanalyze/java/hoisting/Hoist.java, Hoist.loop_guard_hoist(int,int[]):void, 0, PURE_FUNCTION, no_bucket, ERROR, [Side-effect free function void Hoist.loop_guard_hoist(int,int[])]
 codetoanalyze/java/hoisting/Hoist.java, Hoist.loop_guard_hoist(int,int[]):void, 4, INVARIANT_CALL, no_bucket, ERROR, [Loop-invariant call to int Hoist.foo(int,int) at line 65]
+codetoanalyze/java/hoisting/Hoist.java, Hoist.nested_loop_dont_hoist(int,int,int):void, 0, INFINITE_EXECUTION_TIME_CALL, no_bucket, ERROR, []
+codetoanalyze/java/hoisting/Hoist.java, Hoist.nested_loop_dont_hoist(int,int,int):void, 0, PURE_FUNCTION, no_bucket, ERROR, [Side-effect free function void Hoist.nested_loop_dont_hoist(int,int,int)]
+codetoanalyze/java/hoisting/Hoist.java, Hoist.nested_loop_hoist(int,int,int):void, 0, PURE_FUNCTION, no_bucket, ERROR, [Side-effect free function void Hoist.nested_loop_hoist(int,int,int)]
+codetoanalyze/java/hoisting/Hoist.java, Hoist.nested_loop_hoist(int,int,int):void, 4, CONDITION_ALWAYS_FALSE, no_bucket, WARNING, []
 codetoanalyze/java/hoisting/Hoist.java, Hoist.nested_loop_hoist(int,int,int):void, 5, INVARIANT_CALL, no_bucket, ERROR, [Loop-invariant call to int Hoist.foo(int,int) at line 127]
+codetoanalyze/java/hoisting/Hoist.java, Hoist.not_guaranteed_to_execute_dont_hoist(int,int,int):void, 0, PURE_FUNCTION, no_bucket, ERROR, [Side-effect free function void Hoist.not_guaranteed_to_execute_dont_hoist(int,int,int)]
+codetoanalyze/java/hoisting/Hoist.java, Hoist.reassigned_temp_hoist(int):void, 0, PURE_FUNCTION, no_bucket, ERROR, [Side-effect free function void Hoist.reassigned_temp_hoist(int)]
 codetoanalyze/java/hoisting/Hoist.java, Hoist.reassigned_temp_hoist(int):void, 5, INVARIANT_CALL, no_bucket, ERROR, [Loop-invariant call to int Hoist.foo(int,int) at line 45]
+codetoanalyze/java/hoisting/Hoist.java, Hoist.two_function_call_hoist(int):void, 0, PURE_FUNCTION, no_bucket, ERROR, [Side-effect free function void Hoist.two_function_call_hoist(int)]
 codetoanalyze/java/hoisting/Hoist.java, Hoist.two_function_call_hoist(int):void, 4, INVARIANT_CALL, no_bucket, ERROR, [Loop-invariant call to int Hoist.foo(int,int) at line 35]
 codetoanalyze/java/hoisting/Hoist.java, Hoist.two_function_call_hoist(int):void, 4, INVARIANT_CALL, no_bucket, ERROR, [Loop-invariant call to int Hoist.bar(int) at line 35]
 codetoanalyze/java/hoisting/Hoist.java, Hoist.used_in_loop_body_before_def_temp_hoist(int,int[]):void, 6, INVARIANT_CALL, no_bucket, ERROR, [Loop-invariant call to int Hoist.foo(int,int) at line 57]
+codetoanalyze/java/hoisting/Hoist.java, Hoist.void_hoist(int):void, 0, PURE_FUNCTION, no_bucket, ERROR, [Side-effect free function void Hoist.void_hoist(int)]
 codetoanalyze/java/hoisting/Hoist.java, Hoist.void_hoist(int):void, 2, INVARIANT_CALL, no_bucket, ERROR, [Loop-invariant call to void Hoist.dumb_foo() at line 183]
-codetoanalyze/java/hoisting/HoistIndirect.java, HoistIndirect$Test.indirect_modification_dont_hoist_FP(int):int, 5, INVARIANT_CALL, no_bucket, ERROR, [Loop-invariant call to void HoistIndirect$Test.set_test(HoistIndirect$Test) at line 27]
+codetoanalyze/java/hoisting/Hoist.java, Hoist.x_not_invariant_dont_hoist(int,int,int):void, 0, PURE_FUNCTION, no_bucket, ERROR, [Side-effect free function void Hoist.x_not_invariant_dont_hoist(int,int,int)]
+codetoanalyze/java/hoisting/HoistIndirect.java, HoistIndirect$Test.get_test(HoistIndirect$Test):int, 0, PURE_FUNCTION, no_bucket, ERROR, [Side-effect free function int HoistIndirect$Test.get_test(HoistIndirect$Test)]
 codetoanalyze/java/hoisting/HoistIndirect.java, HoistIndirect$Test.indirect_modification_dont_hoist_FP(int):int, 6, INVARIANT_CALL, no_bucket, ERROR, [Loop-invariant call to int HoistIndirect$Test.get_test(HoistIndirect$Test) at line 28]

infer/tests/codetoanalyze/java/hoistingExpensive/HoistExpensive.java

@@ -0,0 +1,35 @@
+/*
+ * Copyright (c) 2018-present, Facebook, Inc.
+ *
+ * This source code is licensed under the MIT license found in the
+ * LICENSE file in the root directory of this source tree.
+ */
+
+class HoistExpensive {
+
+  int incr(int x) {
+    return x + 1;
+  }
+
+  // incr will not be hoisted since it is cheap
+  void cheap_dont_hoist(int size) {
+    int x = 10;
+    for (int i = 0; i < size; i++) {
+      incr(x);
+    }
+  }
+
+  // call to cheap_dont_hoist will be hoisted since it is expensive.
+  void symbolic_expensive_hoist(int size) {
+    for (int i = 0; i < size; i++) {
+      cheap_dont_hoist(size);
+    }
+  }
+
+  // call to cheap_dont_hoist will NOT be hoisted since it is cheap.
+  void instantiated_cheap_hoist(int size) {
+    for (int i = 0; i < size; i++) {
+      cheap_dont_hoist(1);
+    }
+  }
+}

infer/tests/codetoanalyze/java/hoistingExpensive/Makefile

@@ -0,0 +1,12 @@
+# Copyright (c) 2018-present, Facebook, Inc.
+#
+# This source code is licensed under the MIT license found in the
+# LICENSE file in the root directory of this source tree.
+
+TESTS_DIR = ../../..
+
+INFER_OPTIONS = --loop-hoisting-only --hoisting-report-only-expensive  --invariant-by-default --debug-exceptions
+INFERPRINT_OPTIONS = --issues-tests
+SOURCES = $(wildcard *.java)
+
+include $(TESTS_DIR)/javac.make

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

@@ -0,0 +1,5 @@
+codetoanalyze/java/hoistingExpensive/HoistExpensive.java, HoistExpensive.cheap_dont_hoist(int):void, 0, PURE_FUNCTION, no_bucket, ERROR, [Side-effect free function void HoistExpensive.cheap_dont_hoist(int)]
+codetoanalyze/java/hoistingExpensive/HoistExpensive.java, HoistExpensive.incr(int):int, 0, PURE_FUNCTION, no_bucket, ERROR, [Side-effect free function int HoistExpensive.incr(int)]
+codetoanalyze/java/hoistingExpensive/HoistExpensive.java, HoistExpensive.instantiated_cheap_hoist(int):void, 0, PURE_FUNCTION, no_bucket, ERROR, [Side-effect free function void HoistExpensive.instantiated_cheap_hoist(int)]
+codetoanalyze/java/hoistingExpensive/HoistExpensive.java, HoistExpensive.symbolic_expensive_hoist(int):void, 0, PURE_FUNCTION, no_bucket, ERROR, [Side-effect free function void HoistExpensive.symbolic_expensive_hoist(int)]
+codetoanalyze/java/hoistingExpensive/HoistExpensive.java, HoistExpensive.symbolic_expensive_hoist(int):void, 2, INVARIANT_CALL, no_bucket, ERROR, [Loop-invariant call to void HoistExpensive.cheap_dont_hoist(int) at line 25]