1//= ObjCNoReturn.cpp - Handling of Cocoa APIs known not to return --*- C++ -*---
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file implements special handling of recognizing ObjC API hooks that
11// do not return but aren't marked as such in API headers.
12//
13//===----------------------------------------------------------------------===//
14
15#include "clang/AST/ASTContext.h"
16#include "clang/AST/ExprObjC.h"
17#include "clang/Analysis/DomainSpecific/ObjCNoReturn.h"
18
19using namespace clang;
20
21static bool isSubclass(const ObjCInterfaceDecl *Class, IdentifierInfo *II) {
22  if (!Class)
23    return false;
24  if (Class->getIdentifier() == II)
25    return true;
26  return isSubclass(Class->getSuperClass(), II);
27}
28
29ObjCNoReturn::ObjCNoReturn(ASTContext &C)
30  : RaiseSel(GetNullarySelector("raise", C)),
31    NSExceptionII(&C.Idents.get("NSException"))
32{
33  // Generate selectors.
34  SmallVector<IdentifierInfo*, 3> II;
35
36  // raise:format:
37  II.push_back(&C.Idents.get("raise"));
38  II.push_back(&C.Idents.get("format"));
39  NSExceptionInstanceRaiseSelectors[0] =
40    C.Selectors.getSelector(II.size(), &II[0]);
41
42  // raise:format:arguments:
43  II.push_back(&C.Idents.get("arguments"));
44  NSExceptionInstanceRaiseSelectors[1] =
45    C.Selectors.getSelector(II.size(), &II[0]);
46}
47
48
49bool ObjCNoReturn::isImplicitNoReturn(const ObjCMessageExpr *ME) {
50  Selector S = ME->getSelector();
51
52  if (ME->isInstanceMessage()) {
53    // Check for the "raise" message.
54    return S == RaiseSel;
55  }
56
57  if (const ObjCInterfaceDecl *ID = ME->getReceiverInterface()) {
58    if (isSubclass(ID, NSExceptionII)) {
59      for (unsigned i = 0; i < NUM_RAISE_SELECTORS; ++i) {
60        if (S == NSExceptionInstanceRaiseSelectors[i])
61          return true;
62      }
63    }
64  }
65
66  return false;
67}
68