Handle C++ static methods

Summary: public
Add support for translation and calling c++ static methods.
They can be called in two ways:
  ClassName::method()
  classInstance.method()

Both of them have the same meaning, but AST produced is different

Reviewed By: dulmarod

Differential Revision: D2636489

fb-gh-sync-id: 9294a3f

infer/src/clang/cMethod_trans.ml

@@ -29,21 +29,22 @@ type method_call_type =
 
 type function_method_decl_info =
   | Func_decl_info of Clang_ast_t.function_decl_info * Clang_ast_t.type_ptr * CFrontend_config.lang
-  | Cpp_Meth_decl_info of Clang_ast_t.function_decl_info * string * Clang_ast_t.type_ptr
+  | Cpp_Meth_decl_info of Clang_ast_t.function_decl_info * Clang_ast_t.cxx_method_decl_info * string * Clang_ast_t.type_ptr
   | ObjC_Meth_decl_info of Clang_ast_t.obj_c_method_decl_info * string
   | Block_decl_info of Clang_ast_t.block_decl_info * Clang_ast_t.type_ptr * CContext.t
 
 let is_instance_method function_method_decl_info =
   match function_method_decl_info with
   | Func_decl_info _  | Block_decl_info _ -> false
-  | Cpp_Meth_decl_info _ -> true
+  | Cpp_Meth_decl_info (_, method_decl_info, _, _) ->
+      not method_decl_info.Clang_ast_t.xmdi_is_static
   | ObjC_Meth_decl_info (method_decl_info, _) ->
       method_decl_info.Clang_ast_t.omdi_is_instance_method
 
 let get_class_param function_method_decl_info =
   if (is_instance_method function_method_decl_info) then
     match function_method_decl_info with
-    | Cpp_Meth_decl_info (_, class_name, _) ->
+    | Cpp_Meth_decl_info (_, _, class_name, _) ->
         let class_type = Ast_expressions.create_class_type class_name in
         [(CFrontend_config.this, class_type)]
     | ObjC_Meth_decl_info (_, class_name) ->
@@ -55,7 +56,8 @@ let get_class_param function_method_decl_info =
 let get_param_decls function_method_decl_info =
   match function_method_decl_info with
   | Func_decl_info (function_decl_info, _, _)
-  | Cpp_Meth_decl_info (function_decl_info, _, _) -> function_decl_info.Clang_ast_t.fdi_parameters
+  | Cpp_Meth_decl_info (function_decl_info, _, _, _) ->
+      function_decl_info.Clang_ast_t.fdi_parameters
   | ObjC_Meth_decl_info (method_decl_info, _) -> method_decl_info.Clang_ast_t.omdi_parameters
   | Block_decl_info (block_decl_info, _, _) -> block_decl_info.Clang_ast_t.bdi_parameters
 
@@ -80,7 +82,7 @@ let get_parameters function_method_decl_info =
 let get_return_type function_method_decl_info =
   match function_method_decl_info with
   | Func_decl_info (_, typ, _)
-  | Cpp_Meth_decl_info (_, _, typ)
+  | Cpp_Meth_decl_info (_, _, _, typ)
   | Block_decl_info (_, typ, _) -> CTypes.return_type_of_function_type typ
   | ObjC_Meth_decl_info (method_decl_info, _) -> method_decl_info.Clang_ast_t.omdi_result_type
 
@@ -125,7 +127,7 @@ let method_signature_of_decl meth_decl block_data_opt =
       let method_name = name_info.Clang_ast_t.ni_name in
       let class_name = Ast_utils.get_class_name_from_member name_info in
       let procname = General_utils.mk_procname_from_cpp_method class_name method_name tp in
-      let method_decl = Cpp_Meth_decl_info (fdi, class_name, tp)  in
+      let method_decl = Cpp_Meth_decl_info (fdi, mdi, class_name, tp)  in
       let ms = build_method_signature decl_info procname method_decl false false in
       let non_null_instrs = get_assume_not_null_calls ms fdi.Clang_ast_t.fdi_parameters in
       let init_list_instrs = get_init_list_instrs mdi in (* it will be empty for methods *)

infer/src/clang/cTrans.ml

@@ -380,18 +380,25 @@ struct
     let class_name = Ast_utils.get_class_name_from_member name_info in
     Printing.log_out "!!!!! Dealing with method '%s' @." method_name;
     let method_typ = CTypes_decl.type_ptr_to_sil_type context.tenv type_ptr in
-    (* we don't handle C++ static methods yet - when they are called, this might cause a crash *)
-    assert (IList.length pre_trans_result.exps = 1);
-    let (obj_sil, class_typ) = extract_exp_from_list pre_trans_result.exps
-        "WARNING: in Method call we expect to know the object\n" in
+    let is_instance_method =
+      match CMethod_trans.method_signature_of_pointer decl_ptr with
+      | Some ms -> CMethod_signature.ms_is_instance ms
+      | _ -> assert false in (* will happen for generated methods, shouldn't happen right now *)
+    let extra_exps = if is_instance_method then
+        (assert (IList.length pre_trans_result.exps = 1);
+         let (obj_sil, class_typ) = extract_exp_from_list pre_trans_result.exps
+             "WARNING: in Method call we expect to know the object\n" in
+         [(obj_sil, class_typ)])
+      else
+        (* don't add (obj_sil, class_typ) for static methods *)
+        [] in
     (* consider using context.CContext.is_callee_expression to deal with pointers to methods? *)
     (* unlike field access, for method calls there is no need to expand class type *)
     let pname = CMethod_trans.create_procdesc_with_pointer context decl_ptr (Some class_name)
         method_name type_ptr in
     let method_exp = (Sil.Const (Sil.Cfun pname), method_typ) in
     Cfg.set_procname_priority context.CContext.cfg pname;
-    (* TODO for static methods we shouldn't return (obj_sil, class_typ) *)
-    { pre_trans_result with exps = [method_exp; (obj_sil, class_typ)] }
+    { pre_trans_result with exps = [method_exp] @ extra_exps }
 
   let cxxThisExpr_trans trans_state stmt_info expr_info =
     let context = trans_state.context in

infer/tests/codetoanalyze/cpp/frontend/methods/static.cpp

@@ -0,0 +1,24 @@
+/*
+* Copyright (c) 2015 - 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.
+*/
+
+class A {
+public:
+  static int fun(int);
+};
+
+int A::fun(int a) { return 1 / a;}
+
+void div0_class() {
+  A::fun(0);
+}
+
+void div0_instance(A *a) {
+  /* this will call static method as well */
+  a->fun(0);
+}

infer/tests/codetoanalyze/cpp/frontend/methods/static.cpp.dot

@@ -0,0 +1,35 @@
+digraph iCFG {
+9 [label="9:  Call _fun_A_fun \n   n$0=*&a:class A * [line 23]\n  n$1=_fun_A_fun(0:int ) [line 23]\n  REMOVE_TEMPS(n$0,n$1); [line 23]\n  NULLIFY(&a,false); [line 23]\n  APPLY_ABSTRACTION; [line 23]\n " shape="box"]
+	
+
+	 9 -> 8 ;
+8 [label="8: Exit div0_instance \n  " color=yellow style=filled]
+	
+
+7 [label="7: Start div0_instance\nFormals:  a:class A *\nLocals:  \n   DECLARE_LOCALS(&return); [line 21]\n " color=yellow style=filled]
+	
+
+	 7 -> 9 ;
+6 [label="6:  Call _fun_A_fun \n   n$0=_fun_A_fun(0:int ) [line 18]\n  REMOVE_TEMPS(n$0); [line 18]\n  APPLY_ABSTRACTION; [line 18]\n " shape="box"]
+	
+
+	 6 -> 5 ;
+5 [label="5: Exit div0_class \n  " color=yellow style=filled]
+	
+
+4 [label="4: Start div0_class\nFormals: \nLocals:  \n   DECLARE_LOCALS(&return); [line 17]\n " color=yellow style=filled]
+	
+
+	 4 -> 6 ;
+3 [label="3:  Return Stmt \n   n$0=*&a:int  [line 15]\n  *&return:int =(1 / n$0) [line 15]\n  REMOVE_TEMPS(n$0); [line 15]\n  NULLIFY(&a,false); [line 15]\n  APPLY_ABSTRACTION; [line 15]\n " shape="box"]
+	
+
+	 3 -> 2 ;
+2 [label="2: Exit A_fun \n  " color=yellow style=filled]
+	
+
+1 [label="1: Start A_fun\nFormals:  a:int \nLocals:  \n   DECLARE_LOCALS(&return); [line 15]\n " color=yellow style=filled]
+	
+
+	 1 -> 3 ;
+}

infer/tests/endtoend/cpp/StaticMethodTest.java

@@ -0,0 +1,64 @@
+/*
+* Copyright (c) 2015 - 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.cpp;
+
+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 StaticMethodTest {
+
+  public static final String FILE =
+      "infer/tests/codetoanalyze/cpp/frontend/methods/static.cpp";
+
+  private static ImmutableList<String> inferCmd;
+
+  public static final String DIVIDE_BY_ZERO = "DIVIDE_BY_ZERO";
+
+  @ClassRule
+  public static DebuggableTemporaryFolder folder =
+      new DebuggableTemporaryFolder();
+
+  @BeforeClass
+  public static void runInfer() throws InterruptedException, IOException {
+    inferCmd = InferRunner.createCPPInferCommand(folder, FILE);
+  }
+
+  @Test
+  public void whenInferRunsOnDiv0MethodsErrorIsFound()
+      throws InterruptedException, IOException, InferException {
+    InferResults inferResults = InferRunner.runInferCPP(inferCmd);
+    String[] procedures = {
+        "div0_class",
+        "div0_instance",
+    };
+    assertThat(
+        "Results should contain the expected divide by zero",
+        inferResults,
+        containsExactly(
+            DIVIDE_BY_ZERO,
+            FILE,
+            procedures
+        )
+    );
+  }
+}

infer/tests/frontend/cpp/MethodsTest.java

@@ -53,4 +53,9 @@ public class MethodsTest {
     frontendTest("dereference_this.cpp");
   }
 
+  @Test
+  public void testStaticDotFilesMatch()
+      throws InterruptedException, IOException, InferException {
+    frontendTest("static.cpp");
+  }
 }