ubsan_handlers.cc revision 80af605afd0e92a2a128c81898f647207f384e08 
1//===-- ubsan_handlers.cc -------------------------------------------------===//
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// Error logging entry points for the UBSan runtime.
11//
12//===----------------------------------------------------------------------===//
13
14#include "ubsan_handlers.h"
15#include "ubsan_diag.h"
16
17#include "sanitizer_common/sanitizer_common.h"
18
19using namespace __sanitizer;
20using namespace __ubsan;
21
22namespace __ubsan {
23  const char *TypeCheckKinds[] = {
24    "load of", "store to", "reference binding to", "member access within",
25    "member call on", "constructor call on"
26  };
27}
28
29void __ubsan::__ubsan_handle_type_mismatch(TypeMismatchData *Data,
30                                           ValueHandle Pointer) {
31  if (!Pointer)
32    Diag(Data->Loc, "%0 null pointer of type %1")
33      << TypeCheckKinds[Data->TypeCheckKind] << Data->Type;
34  else if (Data->Alignment && (Pointer & (Data->Alignment - 1)))
35    Diag(Data->Loc, "%0 misaligned address %1 for type %3, "
36                    "which requires %2 byte alignment")
37      << TypeCheckKinds[Data->TypeCheckKind] << (void*)Pointer
38      << Data->Alignment << Data->Type;
39  else
40    Diag(Data->Loc, "%0 address %1 with insufficient space "
41                    "for an object of type %2")
42      << TypeCheckKinds[Data->TypeCheckKind] << (void*)Pointer << Data->Type;
43  Die();
44}
45
46/// \brief Common diagnostic emission for various forms of integer overflow.
47template<typename T> static void HandleIntegerOverflow(OverflowData *Data,
48                                                      ValueHandle LHS,
49                                                      const char *Operator,
50                                                      T RHS) {
51  Diag(Data->Loc, "%0 integer overflow: "
52                  "%1 %2 %3 cannot be represented in type %4")
53    << (Data->Type.isSignedIntegerTy() ? "signed" : "unsigned")
54    << Value(Data->Type, LHS) << Operator << RHS << Data->Type;
55  Die();
56}
57
58void __ubsan::__ubsan_handle_add_overflow(OverflowData *Data,
59                                          ValueHandle LHS, ValueHandle RHS) {
60  HandleIntegerOverflow(Data, LHS, "+", Value(Data->Type, RHS));
61}
62
63void __ubsan::__ubsan_handle_sub_overflow(OverflowData *Data,
64                                          ValueHandle LHS, ValueHandle RHS) {
65  HandleIntegerOverflow(Data, LHS, "-", Value(Data->Type, RHS));
66}
67
68void __ubsan::__ubsan_handle_mul_overflow(OverflowData *Data,
69                                          ValueHandle LHS, ValueHandle RHS) {
70  HandleIntegerOverflow(Data, LHS, "*", Value(Data->Type, RHS));
71}
72
73void __ubsan::__ubsan_handle_negate_overflow(OverflowData *Data,
74                                             ValueHandle OldVal) {
75  Diag(Data->Loc, "negation of %0 cannot be represented in type %1; "
76                  "cast to an unsigned type to negate this value to itself")
77    << Value(Data->Type, OldVal) << Data->Type;
78  Die();
79}
80
81void __ubsan::__ubsan_handle_divrem_overflow(OverflowData *Data,
82                                             ValueHandle LHS, ValueHandle RHS) {
83  Value LHSVal(Data->Type, LHS);
84  Value RHSVal(Data->Type, RHS);
85  if (RHSVal.isMinusOne())
86    Diag(Data->Loc, "division of %0 by -1 cannot be represented in type %1")
87      << LHSVal << Data->Type;
88  else
89    Diag(Data->Loc, "division by zero");
90  Die();
91}
92
93void __ubsan::__ubsan_handle_shift_out_of_bounds(ShiftOutOfBoundsData *Data,
94                                                 ValueHandle LHS,
95                                                 ValueHandle RHS) {
96  Value LHSVal(Data->LHSType, LHS);
97  Value RHSVal(Data->RHSType, RHS);
98  if (RHSVal.isNegative())
99    Diag(Data->Loc, "shift exponent %0 is negative") << RHSVal;
100  else if (RHSVal.getPositiveIntValue() >= Data->LHSType.getIntegerBitWidth())
101    Diag(Data->Loc, "shift exponent %0 is too large for %1-bit type %2")
102      << RHSVal << Data->LHSType.getIntegerBitWidth() << Data->LHSType;
103  else if (LHSVal.isNegative())
104    Diag(Data->Loc, "left shift of negative value %0") << LHSVal;
105  else
106    Diag(Data->Loc, "left shift of %0 by %1 places cannot be represented "
107                    "in type %2") << LHSVal << RHSVal << Data->LHSType;
108  Die();
109}
110
111void __ubsan::__ubsan_handle_builtin_unreachable(UnreachableData *Data) {
112  Diag(Data->Loc, "execution reached a __builtin_unreachable() call");
113  Die();
114}
115
116void __ubsan::__ubsan_handle_missing_return(UnreachableData *Data) {
117  Diag(Data->Loc, "execution reached the end of a value-returning function "
118                  "without returning a value");
119  Die();
120}
121
122void __ubsan::__ubsan_handle_vla_bound_not_positive(VLABoundData *Data,
123                                                    ValueHandle Bound) {
124  Diag(Data->Loc, "variable length array bound evaluates to "
125                  "non-positive value %0")
126    << Value(Data->Type, Bound);
127  Die();
128}
129
130void __ubsan::__ubsan_handle_float_cast_overflow(FloatCastOverflowData *Data,
131                                                 ValueHandle From) {
132  Diag(SourceLocation(), "value %0 is outside the range of representable "
133                         "values of type %2")
134    << Value(Data->FromType, From) << Data->FromType << Data->ToType;
135  Die();
136}
137