[backend] don't run preanalysis twice

Reviewed By: jeremydubreil

Differential Revision: D3982521

fbshipit-source-id: edb22e9

infer/src/IR/Cfg.re

@@ -512,6 +512,11 @@ let module Node = {
     proc_desc.pd_attributes.ProcAttributes.locals =
       proc_desc.pd_attributes.ProcAttributes.locals @ new_locals;
 
+  /** check or indicate if we have performed preanalysis on the CFG */
+  let proc_desc_did_preanalysis proc_desc => proc_desc.pd_attributes.ProcAttributes.did_preanalysis;
+  let proc_desc_signal_did_preanalysis proc_desc =>
+    proc_desc.pd_attributes.ProcAttributes.did_preanalysis = true;
+
   /** Print extended instructions for the node,
       highlighting the given subinstruction if present */
   let pp_instrs pe0 sub_instrs::sub_instrs instro fmt node => {
@@ -784,6 +789,8 @@ let module Procdesc = {
   let compute_distance_to_exit_node = Node.proc_desc_compute_distance_to_exit_node;
   let create = Node.proc_desc_create;
   let remove = Node.proc_desc_remove;
+  let did_preanalysis = Node.proc_desc_did_preanalysis;
+  let signal_did_preanalysis = Node.proc_desc_signal_did_preanalysis;
   let find_from_name = Node.proc_desc_from_name;
   let get_attributes = Node.proc_desc_get_attributes;
   let get_err_log = Node.proc_desc_get_err_log;

infer/src/IR/Cfg.rei

@@ -41,6 +41,12 @@ let module Procdesc: {
   /** Create a procdesc */
   let create: cfg => ProcAttributes.t => t;
 
+  /** true if we ran the preanalysis on the CFG associated with [t] */
+  let did_preanalysis: t => bool;
+
+  /** indicate that we have performed preanalysis on the CFG assoociated with [t] */
+  let signal_did_preanalysis: t => unit;
+
   /** [remove cfg name remove_nodes] remove the procdesc [name]
       from the control flow graph [cfg]. */
   /** It also removes all the nodes from the procedure from the cfg if remove_nodes is true */

infer/src/IR/ProcAttributes.re

@@ -26,6 +26,7 @@ type t = {
   access: PredSymb.access, /** visibility access */
   captured: list (Mangled.t, Typ.t), /** name and type of variables captured in blocks */
   mutable changed: bool, /** true if proc has changed since last analysis */
+  mutable did_preanalysis: bool, /** true if we performed preanalysis on the CFG for this proc */
   err_log: Errlog.t, /** Error log for the procedure */
   exceptions: list string, /** exceptions thrown by the procedure */
   formals: list (Mangled.t, Typ.t), /** name and type of formal parameters */
@@ -53,6 +54,7 @@ let default proc_name language => {
   access: PredSymb.Default,
   captured: [],
   changed: true,
+  did_preanalysis: false,
   err_log: Errlog.empty (),
   exceptions: [],
   formals: [],

infer/src/IR/ProcAttributes.rei

@@ -20,6 +20,7 @@ type t = {
   access: PredSymb.access, /** visibility access */
   captured: list (Mangled.t, Typ.t), /** name and type of variables captured in blocks */
   mutable changed: bool, /** true if proc has changed since last analysis */
+  mutable did_preanalysis: bool, /** true if we performed preanalysis on the CFG for this proc */
   err_log: Errlog.t, /** Error log for the procedure */
   exceptions: list string, /** exceptions thrown by the procedure */
   formals: list (Mangled.t, Typ.t), /** name and type of formal parameters */

infer/src/backend/preanal.ml

@@ -291,11 +291,16 @@ let do_liveness pdesc tenv =
   LivenessAnalysis.exec_cfg liveness_proc_cfg (ProcData.make_default pdesc tenv)
 
 let doit pdesc cg tenv =
-  if Config.copy_propagation then do_copy_propagation pdesc tenv;
-  let liveness_inv_map = do_liveness pdesc tenv in
-  if not (Config.lazy_dynamic_dispatch) && Config.copy_propagation
-  then remove_dead_frontend_stores pdesc liveness_inv_map;
-  add_nullify_instrs pdesc tenv liveness_inv_map;
-  if not Config.lazy_dynamic_dispatch
-  then add_dispatch_calls pdesc cg tenv;
-  add_abstraction_instructions pdesc;
+  if not (Cfg.Procdesc.did_preanalysis pdesc)
+  then
+    begin
+      Cfg.Procdesc.signal_did_preanalysis pdesc;
+      if Config.copy_propagation then do_copy_propagation pdesc tenv;
+      let liveness_inv_map = do_liveness pdesc tenv in
+      if not (Config.lazy_dynamic_dispatch) && Config.copy_propagation
+      then remove_dead_frontend_stores pdesc liveness_inv_map;
+      add_nullify_instrs pdesc tenv liveness_inv_map;
+      if not Config.lazy_dynamic_dispatch
+      then add_dispatch_calls pdesc cg tenv;
+      add_abstraction_instructions pdesc;
+    end

infer/src/quandary/TaintAnalysis.ml

@@ -434,6 +434,8 @@ module Make (TraceDomain : QuandarySummary.Trace) = struct
           (fun formal_map (base, index) -> AccessPath.BaseMap.add base index formal_map)
           AccessPath.BaseMap.empty
           formals_with_nums in
+
+      Preanal.doit pdesc dummy_cg tenv;
       let formals = make_formal_access_paths pdesc in
       let proc_data = ProcData.make pdesc tenv formals in
       match Analyzer.compute_post proc_data with
@@ -452,7 +454,6 @@ module Make (TraceDomain : QuandarySummary.Trace) = struct
     if Ondemand.procedure_should_be_analyzed proc_name
     then
       begin
-        Preanal.doit proc_desc dummy_cg tenv;
         Ondemand.set_callbacks callbacks;
         analyze_ondemand DB.source_file_empty proc_desc;
         Ondemand.unset_callbacks ();