Translate global const vars locally to a procedure

Summary: With this approach, all the global consts will be inlined in the places where they are used.

Reviewed By: dulmarod

Differential Revision: D3703133

fbshipit-source-id: 3c19479

infer/src/clang/cTrans.ml

@@ -472,39 +472,6 @@ struct
         { empty_res_trans with exps = [(Exp.Const (Const.Cfun pname), typ)] }
       end
 
-  let var_deref_trans trans_state stmt_info decl_ref =
-    let open CContext in
-    let context = trans_state.context in
-    let _, _, type_ptr = Ast_utils.get_info_from_decl_ref decl_ref in
-    let ast_typ = CTypes_decl.type_ptr_to_sil_type context.tenv type_ptr in
-    let typ = match ast_typ with
-      | Typ.Tstruct _ when decl_ref.Clang_ast_t.dr_kind = `ParmVar ->
-          if General_utils.is_cpp_translation Config.clang_lang then
-            Typ.Tptr (ast_typ, Typ.Pk_reference)
-          else ast_typ
-      | _ -> ast_typ in
-    let procname = Cfg.Procdesc.get_proc_name context.procdesc in
-    let sil_loc = CLocation.get_sil_location stmt_info context in
-    let pvar = CVar_decl.sil_var_of_decl_ref context decl_ref procname in
-    CContext.add_block_static_var context procname (pvar, typ);
-    let e = Exp.Lvar pvar in
-    let exps = if Self.is_var_self pvar (CContext.is_objc_method context) then
-        let curr_class = CContext.get_curr_class context in
-        if (CTypes.is_class typ) then
-          raise (Self.SelfClassException (CContext.get_curr_class_name curr_class))
-        else
-          let typ = CTypes.add_pointer_to_typ
-              (CTypes_decl.get_type_curr_class_objc context.tenv curr_class) in
-          [(e, typ)]
-      else [(e, typ)] in
-    Printing.log_out "\n\n PVAR ='%s'\n\n" (Pvar.to_string pvar);
-    let res_trans = { empty_res_trans with exps = exps } in
-    match typ with
-    | Typ.Tptr (_, Typ.Pk_reference) ->
-        (* dereference pvar due to the behavior of reference types in clang's AST *)
-        dereference_value_from_result sil_loc res_trans ~strip_pointer:true
-    | _ -> res_trans
-
   let field_deref_trans trans_state stmt_info pre_trans_result decl_ref ~is_constructor_init =
     let open CContext in
     let context = trans_state.context in
@@ -632,6 +599,57 @@ struct
     Cfg.Node.set_succs_exn trans_state.context.cfg root_node' res_trans.root_nodes [];
     { empty_res_trans with root_nodes = [root_node']; leaf_nodes = trans_state.succ_nodes }
 
+  and var_deref_trans trans_state stmt_info (decl_ref : Clang_ast_t.decl_ref) =
+    let context = trans_state.context in
+    let _, _, type_ptr = Ast_utils.get_info_from_decl_ref decl_ref in
+    let ast_typ = CTypes_decl.type_ptr_to_sil_type context.tenv type_ptr in
+    let typ = match ast_typ with
+      | Tstruct _ when decl_ref.dr_kind = `ParmVar ->
+          if General_utils.is_cpp_translation Config.clang_lang then
+            Typ.Tptr (ast_typ, Pk_reference)
+          else ast_typ
+      | _ -> ast_typ in
+    let procname = Cfg.Procdesc.get_proc_name context.procdesc in
+    let sil_loc = CLocation.get_sil_location stmt_info context in
+    let pvar = CVar_decl.sil_var_of_decl_ref context decl_ref procname in
+    CContext.add_block_static_var context procname (pvar, typ);
+    let var_exp = Exp.Lvar pvar in
+    (* handle references to global const *)
+    (* if there's a reference to a global const, add a fake instruction that *)
+    (* assigns the global again to its initialization value right before the *)
+    (* place where it is used *)
+    let trans_result' =
+      let is_global_const, init_expr =
+        match Ast_utils.get_decl decl_ref.dr_decl_pointer with
+        | Some VarDecl (_, _, qual_type, vdi) ->
+            (match ast_typ with
+             | Tstruct _
+               when not (General_utils.is_cpp_translation Config.clang_lang) ->
+                 (* Do not convert a global struct to a local because SIL
+                    values do not include structs, they must all be heap-allocated  *)
+                 false, None
+             | _ -> vdi.vdi_is_global && qual_type.is_const, vdi.vdi_init_expr)
+        | _ -> false, None in
+      if is_global_const then
+        init_expr_trans trans_state (var_exp, typ) stmt_info init_expr
+      else empty_res_trans in
+    let exps = if Self.is_var_self pvar (CContext.is_objc_method context) then
+        let curr_class = CContext.get_curr_class context in
+        if (CTypes.is_class typ) then
+          raise (Self.SelfClassException (CContext.get_curr_class_name curr_class))
+        else
+          let typ = CTypes.add_pointer_to_typ
+              (CTypes_decl.get_type_curr_class_objc context.tenv curr_class) in
+          [(var_exp, typ)]
+      else [(var_exp, typ)] in
+    Printing.log_out "\n\n PVAR ='%s'\n\n" (Pvar.to_string pvar);
+    let res_trans = { trans_result' with exps } in
+    match typ with
+    | Tptr (_, Pk_reference) ->
+        (* dereference pvar due to the behavior of reference types in clang's AST *)
+        dereference_value_from_result sil_loc res_trans ~strip_pointer:true
+    | _ -> res_trans
+
   and decl_ref_trans trans_state pre_trans_result stmt_info decl_ref ~is_constructor_init =
     Printing.log_out "  priority node free = '%s'\n@."
       (string_of_bool (PriorityNode.is_priority_free trans_state));

infer/tests/codetoanalyze/cpp/frontend/global_const/global_const1.cpp

@@ -0,0 +1,22 @@
+/*
+ * Copyright (c) 2016 - present Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+
+struct X {
+  X() {}
+};
+const X global;
+
+X test() { return global; }
+
+static const int v = 2;
+
+int test2() {
+  int local = v;
+  return v;
+}

infer/tests/codetoanalyze/cpp/frontend/global_const/global_const1.cpp.dot

@@ -0,0 +1,43 @@
+/* @generated */
+digraph iCFG {
+11 [label="11:  DeclStmt \n   *&#GB$v:int =2 [line 20]\n  n$1=*&#GB$v:int  [line 20]\n  *&local:int =n$1 [line 20]\n " shape="box"]
+	
+
+	 11 -> 10 ;
+10 [label="10:  Return Stmt \n   *&#GB$v:int =2 [line 21]\n  n$0=*&#GB$v:int  [line 21]\n  *&return:int =n$0 [line 21]\n " shape="box"]
+	
+
+	 10 -> 9 ;
+9 [label="9: Exit test2 \n  " color=yellow style=filled]
+	
+
+8 [label="8: Start test2\nFormals: \nLocals:  local:int  \n   DECLARE_LOCALS(&return,&local); [line 19]\n " color=yellow style=filled]
+	
+
+	 8 -> 11 ;
+7 [label="7:  Return Stmt \n   n$0=*&__return_param:class X * [line 15]\n  _fun_X_X(&#GB$global:class X *) [line 13]\n  _fun_X_X(n$0:class X *,&#GB$global:class X &) [line 15]\n " shape="box"]
+	
+
+	 7 -> 6 ;
+6 [label="6: Exit test \n  " color=yellow style=filled]
+	
+
+5 [label="5: Start test\nFormals:  __return_param:class X *\nLocals:  \n   DECLARE_LOCALS(&return); [line 15]\n " color=yellow style=filled]
+	
+
+	 5 -> 7 ;
+4 [label="4: Exit X_X \n  " color=yellow style=filled]
+	
+
+3 [label="3: Start X_X\nFormals:  this:class X * __param_0:class X &\nLocals:  \n   DECLARE_LOCALS(&return); [line 10]\n " color=yellow style=filled]
+	
+
+	 3 -> 4 ;
+2 [label="2: Exit X_X \n  " color=yellow style=filled]
+	
+
+1 [label="1: Start X_X\nFormals:  this:class X *\nLocals:  \n   DECLARE_LOCALS(&return); [line 11]\n " color=yellow style=filled]
+	
+
+	 1 -> 2 ;
+}

infer/tests/codetoanalyze/cpp/frontend/global_const/global_const2.cpp

@@ -0,0 +1,11 @@
+/*
+ * Copyright (c) 2016 - present Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+
+const int global = 1 ? 2 : 3;
+int test() { return global; }

infer/tests/codetoanalyze/cpp/frontend/global_const/global_const2.cpp.dot

@@ -0,0 +1,35 @@
+/* @generated */
+digraph iCFG {
+8 [label="8:  Return Stmt \n   n$1=*&0$?%__sil_tmpSIL_temp_conditional___n$0:int  [line 10]\n  *&#GB$global:int =n$1 [line 11]\n  n$2=*&#GB$global:int  [line 11]\n  *&return:int =n$2 [line 11]\n " shape="box"]
+	
+
+	 8 -> 2 ;
+7 [label="7:  ConditinalStmt Branch \n   *&0$?%__sil_tmpSIL_temp_conditional___n$0:int =3 [line 10]\n " shape="box"]
+	
+
+	 7 -> 3 ;
+6 [label="6:  ConditinalStmt Branch \n   *&0$?%__sil_tmpSIL_temp_conditional___n$0:int =2 [line 10]\n " shape="box"]
+	
+
+	 6 -> 3 ;
+5 [label="5: Prune (false branch) \n   PRUNE((1 == 0), false); [line 10]\n " shape="invhouse"]
+	
+
+	 5 -> 7 ;
+4 [label="4: Prune (true branch) \n   PRUNE((1 != 0), true); [line 10]\n " shape="invhouse"]
+	
+
+	 4 -> 6 ;
+3 [label="3: + \n  " ]
+	
+
+	 3 -> 8 ;
+2 [label="2: Exit test \n  " color=yellow style=filled]
+	
+
+1 [label="1: Start test\nFormals: \nLocals:  0$?%__sil_tmpSIL_temp_conditional___n$0:int  \n   DECLARE_LOCALS(&return,&0$?%__sil_tmpSIL_temp_conditional___n$0); [line 11]\n " color=yellow style=filled]
+	
+
+	 1 -> 4 ;
+	 1 -> 5 ;
+}

infer/tests/codetoanalyze/cpp/frontend/namespace/namespace.cpp.dot

@@ -32,7 +32,7 @@ digraph iCFG {
 	
 
 	 17 -> 16 ;
-16 [label="16:  BinaryOperatorStmt: Assign \n   n$0=*&#GB$bar::pi:double  [line 57]\n  *&j:double =n$0 [line 57]\n " shape="box"]
+16 [label="16:  BinaryOperatorStmt: Assign \n   *&#GB$bar::pi:double =3.141600 [line 57]\n  n$0=*&#GB$bar::pi:double  [line 57]\n  *&j:double =n$0 [line 57]\n " shape="box"]
 	
 
 	 16 -> 15 ;
@@ -54,7 +54,7 @@ digraph iCFG {
 	
 
 	 11 -> 12 ;
-10 [label="10:  Return Stmt \n   n$0=*&#GB$bar::pi:double  [line 30]\n  *&return:double =(2 * n$0) [line 30]\n " shape="box"]
+10 [label="10:  Return Stmt \n   *&#GB$bar::pi:double =3.141600 [line 30]\n  n$0=*&#GB$bar::pi:double  [line 30]\n  *&return:double =(2 * n$0) [line 30]\n " shape="box"]
 	
 
 	 10 -> 9 ;

infer/tests/codetoanalyze/objc/errors/global_const/global_const.m

@@ -0,0 +1,33 @@
+/*
+ * Copyright (c) 2016 - present Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+
+#import <Foundation/Foundation.h>
+
+static NSString* const GlobalConst = @"A Global Const!";
+static NSString* Global = @"A Global!";
+
+@interface SimpleRoot : NSObject
+
+@end
+
+@implementation SimpleRoot
+
+- (void)doSomethingOkWithDict:(NSMutableDictionary*)dict
+                    andString:(NSString*)input {
+  NSString* str = [GlobalConst stringByAppendingString:input];
+  [dict removeObjectForKey:str];
+}
+
+- (void)doSomethingBadWithDict:(NSMutableDictionary*)dict
+                     andString:(NSString*)input {
+  NSString* str = [Global stringByAppendingString:input];
+  [dict removeObjectForKey:str];
+}
+
+@end

infer/tests/codetoanalyze/objcpp/frontend/global_const/global_const.mm

@@ -0,0 +1,20 @@
+/*
+ * Copyright (c) 2016 - present Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+
+typedef struct {
+  float field1;
+  float field2;
+  float field3;
+} Fields;
+
+static const Fields __someFields = {
+    .field1 = 1, .field2 = 2, .field3 = 3,
+};
+
+Fields fields() { return __someFields; }

infer/tests/codetoanalyze/objcpp/frontend/global_const/global_const.mm.dot

@@ -0,0 +1,33 @@
+/* @generated */
+digraph iCFG {
+8 [label="8:  Return Stmt \n   n$0=*&__return_param:class Fields * [line 20]\n  *&#GB$__someFields.field1:float =1 [line 16]\n  *&#GB$__someFields.field2:float =2 [line 16]\n  *&#GB$__someFields.field3:float =3 [line 16]\n  _fun_Fields_(n$0:class Fields *,&#GB$__someFields:class Fields &) [line 20]\n " shape="box"]
+	
+
+	 8 -> 7 ;
+7 [label="7: Exit fields \n  " color=yellow style=filled]
+	
+
+6 [label="6: Start fields\nFormals:  __return_param:class Fields *\nLocals:  \n   DECLARE_LOCALS(&return); [line 20]\n " color=yellow style=filled]
+	
+
+	 6 -> 8 ;
+5 [label="5:  Constructor Init \n   n$6=*&this:class Fields * [line 10]\n  n$7=*&__param_0:class Fields & [line 10]\n  n$8=*n$7.field1:float  [line 10]\n  *n$6.field1:float =n$8 [line 10]\n " shape="box"]
+	
+
+	 5 -> 4 ;
+4 [label="4:  Constructor Init \n   n$3=*&this:class Fields * [line 10]\n  n$4=*&__param_0:class Fields & [line 10]\n  n$5=*n$4.field2:float  [line 10]\n  *n$3.field2:float =n$5 [line 10]\n " shape="box"]
+	
+
+	 4 -> 3 ;
+3 [label="3:  Constructor Init \n   n$0=*&this:class Fields * [line 10]\n  n$1=*&__param_0:class Fields & [line 10]\n  n$2=*n$1.field3:float  [line 10]\n  *n$0.field3:float =n$2 [line 10]\n " shape="box"]
+	
+
+	 3 -> 2 ;
+2 [label="2: Exit Fields_ \n  " color=yellow style=filled]
+	
+
+1 [label="1: Start Fields_\nFormals:  this:class Fields * __param_0:class Fields &\nLocals:  \n   DECLARE_LOCALS(&return); [line 10]\n " color=yellow style=filled]
+	
+
+	 1 -> 5 ;
+}

infer/tests/endtoend/objc/infer/GlobalConstNPETest.java

@@ -0,0 +1,57 @@
+/*
+ * Copyright (c) 2016 - present Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+
+package endtoend.objc.infer;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static utils.matchers.ResultContainsExactly.containsExactly;
+
+import com.google.common.collect.ImmutableList;
+
+import org.junit.BeforeClass;
+import org.junit.ClassRule;
+import org.junit.Test;
+
+import java.io.IOException;
+
+import utils.DebuggableTemporaryFolder;
+import utils.InferException;
+import utils.InferResults;
+import utils.InferRunner;
+
+public class GlobalConstNPETest {
+
+  public static final String FILE =
+      "infer/tests/codetoanalyze/objc/errors/global_const/global_const.m";
+
+  private static ImmutableList<String> inferCmd;
+
+  public static final String NULL_DEREFERENCE = "NULL_DEREFERENCE";
+
+  @ClassRule
+  public static DebuggableTemporaryFolder folder =
+      new DebuggableTemporaryFolder();
+
+  @BeforeClass
+  public static void runInfer() throws InterruptedException, IOException {
+    inferCmd = InferRunner.createObjCInferCommand(folder, FILE);
+  }
+
+  @Test
+  public void whenInferRunsOnMain1ThenDivideByZeroIsFound()
+      throws InterruptedException, IOException, InferException {
+    InferResults inferResults = InferRunner.runInferObjC(inferCmd);
+    String[] procedures = {"doSomethingBadWithDict:andString:"};
+    assertThat(
+        "Results should contain the expected " + NULL_DEREFERENCE,
+        inferResults,
+        containsExactly(NULL_DEREFERENCE, FILE, procedures)
+    );
+  }
+}

infer/tests/frontend/cpp/GlobalConstTest.java

@@ -0,0 +1,33 @@
+/*
+ * Copyright (c) 2016 - present Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+
+package frontend.cpp;
+
+import org.junit.Rule;
+import org.junit.Test;
+
+import java.io.IOException;
+
+import utils.ClangFrontendUtils;
+import utils.DebuggableTemporaryFolder;
+import utils.InferException;
+
+public class GlobalConstTest {
+
+  @Rule
+  public DebuggableTemporaryFolder folder = new DebuggableTemporaryFolder();
+
+  @Test
+  public void whenCaptureRunCommaThenDotFilesAreTheSame()
+      throws InterruptedException, IOException, InferException {
+    String src =
+        "infer/tests/codetoanalyze/cpp/frontend/global_const/global_const1.cpp";
+    ClangFrontendUtils.createAndCompareCppDotFiles(folder, src);
+  }
+}

infer/tests/frontend/cpp/GlobalConstTest2.java

@@ -0,0 +1,33 @@
+/*
+ * Copyright (c) 2016 - present Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+
+package frontend.cpp;
+
+import org.junit.Rule;
+import org.junit.Test;
+
+import java.io.IOException;
+
+import utils.ClangFrontendUtils;
+import utils.DebuggableTemporaryFolder;
+import utils.InferException;
+
+public class GlobalConstTest2 {
+
+  @Rule
+  public DebuggableTemporaryFolder folder = new DebuggableTemporaryFolder();
+
+  @Test
+  public void whenCaptureRunCommaThenDotFilesAreTheSame()
+      throws InterruptedException, IOException, InferException {
+    String src =
+        "infer/tests/codetoanalyze/cpp/frontend/global_const/global_const2.cpp";
+    ClangFrontendUtils.createAndCompareCppDotFiles(folder, src);
+  }
+}

infer/tests/frontend/objcpp/GlobalConstTest.java

@@ -0,0 +1,49 @@
+/*
+ * Copyright (c) 2016 - present Facebook, Inc.
+ * All rights reserved.
+ *
+ * This source code is licensed under the BSD style license found in the
+ * LICENSE file in the root directory of this source tree. An additional grant
+ * of patent rights can be found in the PATENTS file in the same directory.
+ */
+
+package frontend.objcpp;
+
+import static org.hamcrest.MatcherAssert.assertThat;
+import static utils.matchers.DotFilesEqual.dotFileEqualTo;
+
+import com.google.common.collect.ImmutableList;
+
+import org.junit.Rule;
+import org.junit.Test;
+
+import java.io.File;
+import java.io.IOException;
+
+import utils.DebuggableTemporaryFolder;
+import utils.InferException;
+import utils.InferRunner;
+
+public class GlobalConstTest {
+
+  @Rule
+  public DebuggableTemporaryFolder folder = new DebuggableTemporaryFolder();
+
+  @Test
+  public void whenCaptureRunSwitchStmtThenDotFilesAreTheSame()
+      throws InterruptedException, IOException, InferException {
+    String switch_src =
+        "infer/tests/codetoanalyze/objcpp/frontend/global_const/global_const.mm";
+
+    String switch_dotty =
+        "infer/tests/codetoanalyze/objcpp/frontend/global_const/global_const.mm.dot";
+
+    ImmutableList<String> inferCmd =
+        InferRunner.createObjCPPInferCommand(folder, switch_src);
+    File newDotFile = InferRunner.runInferFrontend(inferCmd);
+    assertThat(
+        "In the capture of " + switch_src +
+            " the dotty files should be the same.",
+        newDotFile, dotFileEqualTo(switch_dotty));
+  }
+}