1//= ObjCNoReturn.cpp - Handling of Cocoa APIs known not to return --*- C++ -*---
2//
3// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4// See https://llvm.org/LICENSE.txt for license information.
5// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6//
7//===----------------------------------------------------------------------===//
8//
9// This file implements special handling of recognizing ObjC API hooks that
10// do not return but aren't marked as such in API headers.
11//
12//===----------------------------------------------------------------------===//
13
14#include "clang/AST/ASTContext.h"
15#include "clang/AST/ExprObjC.h"
16#include "clang/Analysis/DomainSpecific/ObjCNoReturn.h"
17
18using namespace clang;
19
20static bool isSubclass(const ObjCInterfaceDecl *Class, IdentifierInfo *II) {
21  if (!Class)
22    return false;
23  if (Class->getIdentifier() == II)
24    return true;
25  return isSubclass(Class->getSuperClass(), II);
26}
27
28ObjCNoReturn::ObjCNoReturn(ASTContext &C)
29  : RaiseSel(GetNullarySelector("raise", C)),
30    NSExceptionII(&C.Idents.get("NSException"))
31{
32  // Generate selectors.
33  SmallVector<IdentifierInfo*, 3> II;
34
35  // raise:format:
36  II.push_back(&C.Idents.get("raise"));
37  II.push_back(&C.Idents.get("format"));
38  NSExceptionInstanceRaiseSelectors[0] =
39    C.Selectors.getSelector(II.size(), &II[0]);
40
41  // raise:format:arguments:
42  II.push_back(&C.Idents.get("arguments"));
43  NSExceptionInstanceRaiseSelectors[1] =
44    C.Selectors.getSelector(II.size(), &II[0]);
45}
46
47
48bool ObjCNoReturn::isImplicitNoReturn(const ObjCMessageExpr *ME) {
49  Selector S = ME->getSelector();
50
51  if (ME->isInstanceMessage()) {
52    // Check for the "raise" message.
53    return S == RaiseSel;
54  }
55
56  if (const ObjCInterfaceDecl *ID = ME->getReceiverInterface()) {
57    if (isSubclass(ID, NSExceptionII)) {
58      for (unsigned i = 0; i < NUM_RAISE_SELECTORS; ++i) {
59        if (S == NSExceptionInstanceRaiseSelectors[i])
60          return true;
61      }
62    }
63  }
64
65  return false;
66}
67