clang/test/Analysis/cast-value-notes.cpp

   1 // RUN: %clang_analyze_cc1 -std=c++14 -triple amdgcn-unknown-unknown \
   2 // RUN: -analyzer-checker=core,apiModeling.llvm.CastValue,debug.ExprInspection\
   3 // RUN: -analyzer-output=text -verify -DX86 -DSUPPRESSED %s 2>&1 | FileCheck %s -check-prefix=X86-CHECK
   4 //
   5 // RUN: %clang_analyze_cc1 -std=c++14 -triple amdgcn-unknown-unknown \
   6 // RUN: -analyzer-checker=core,apiModeling.llvm.CastValue,debug.ExprInspection\
   7 // RUN:  -analyzer-config core.NullDereference:SuppressAddressSpaces=false\
   8 // RUN:  -analyzer-output=text -verify -DX86 -DNOT_SUPPRESSED %s 2>&1 | FileCheck %s -check-prefix=X86-CHECK
   9 //
  10 // RUN: %clang_analyze_cc1 -std=c++14 -triple amdgcn-unknown-unknown \
  11 // RUN: -analyzer-checker=core,apiModeling.llvm.CastValue,debug.ExprInspection\
  12 // RUN:  -analyzer-config core.NullDereference:SuppressAddressSpaces=true\
  13 // RUN:  -analyzer-output=text -verify -DX86 -DSUPPRESSED %s 2>&1 | FileCheck %s -check-prefix=X86-CHECK
  14 //
  15 // RUN: %clang_analyze_cc1 -std=c++14 -triple x86_64-unknown-unknown \
  16 // RUN:  -analyzer-checker=core,apiModeling.llvm.CastValue,debug.ExprInspection\
  17 // RUN:  -analyzer-output=text -verify -DX86 -DSUPPRESSED %s 2>&1 | FileCheck %s --check-prefix=X86-CHECK
  18 //
  19 // RUN: %clang_analyze_cc1 -std=c++14 -triple x86_64-unknown-unknown \
  20 // RUN:  -analyzer-checker=core,apiModeling.llvm.CastValue,debug.ExprInspection\
  21 // RUN:  -analyzer-config core.NullDereference:SuppressAddressSpaces=true\
  22 // RUN:  -analyzer-output=text -verify -DX86 -DSUPPRESSED %s 2>&1 | FileCheck %s --check-prefix=X86-CHECK-SUPPRESSED
  23 //
  24 // RUN: %clang_analyze_cc1 -std=c++14 -triple x86_64-unknown-unknown \
  25 // RUN:  -analyzer-checker=core,apiModeling.llvm.CastValue,debug.ExprInspection\
  26 // RUN:  -analyzer-config core.NullDereference:SuppressAddressSpaces=false\
  27 // RUN:  -analyzer-output=text -verify -DX86 -DNOT_SUPPRESSED %s 2>&1 | FileCheck %s --check-prefix=X86-CHECK
  28 //
  29 // RUN: %clang_analyze_cc1 -std=c++14 -triple mips-unknown-unknown \
  30 // RUN: -analyzer-checker=core,apiModeling.llvm.CastValue,debug.ExprInspection\
  31 // RUN: -analyzer-output=text -verify -DMIPS %s 2>&1
  32 //
  33 // RUN: %clang_analyze_cc1 -std=c++14 -triple mips-unknown-unknown \
  34 // RUN: -analyzer-checker=core,apiModeling.llvm.CastValue,debug.ExprInspection\
  35 // RUN: -analyzer-config core.NullDereference:SuppressAddressSpaces=false\
  36 // RUN: -analyzer-output=text -verify -DMIPS %s 2>&1
  37 //
  38 // RUN: %clang_analyze_cc1 -std=c++14 -triple mips-unknown-unknown \
  39 // RUN: -analyzer-checker=core,apiModeling.llvm.CastValue,debug.ExprInspection\
  40 // RUN: -analyzer-config core.NullDereference:SuppressAddressSpaces=true\
  41 // RUN: -analyzer-output=text -verify -DMIPS_SUPPRESSED %s
  42
  43 #include "Inputs/llvm.h"
  44
  45 // The amggcn triple case uses an intentionally different address space.
  46 // The core.NullDereference checker intentionally ignores checks
  47 // that use address spaces, so the case is differentiated here.
  48 //
  49 // From https://llvm.org/docs/AMDGPUUsage.html#address-spaces,
  50 // select address space 3 (local), since the pointer size is
  51 // different than Generic.
  52 #define DEVICE __attribute__((address_space(3)))
  53
  54 namespace clang {
  55 struct Shape {
  56   template <typename T>
  57   const T *castAs() const;
  58
  59   template <typename T>
  60   const T *getAs() const;
  61 };
  62 class Triangle : public Shape {};
  63 class Rectangle : public Shape {};
  64 class Hexagon : public Shape {};
  65 class Circle : public Shape {};
  66 } // namespace clang
  67
  68 using namespace llvm;
  69 using namespace clang;
  70
  71 void clang_analyzer_printState();
  72
  73 #if defined(X86)
  74 void evalReferences(const Shape &S) {
  75   const auto &C = dyn_cast<Circle>(S);
  76   // expected-note@-1 {{Assuming 'S' is not a 'const class clang::Circle &'}}
  77   // expected-note@-2 {{Dereference of null pointer}}
  78   // expected-warning@-3 {{Dereference of null pointer}}
  79   clang_analyzer_printState();
  80   // XX86-CHECK:      "dynamic_types": [
  81   // XX86-CHECK-NEXT:   { "region": "SymRegion{reg_$0<const struct clang::Shape & S>}", "dyn_type": "const class clang::Circle &", "sub_classable": true }
  82   (void)C;
  83 }
  84 #if defined(SUPPRESSED)
  85 void evalReferences_addrspace(const Shape &S) {
  86   const auto &C = dyn_cast<DEVICE Circle>(S);
  87   clang_analyzer_printState();
  88   // X86-CHECK-SUPPRESSED: "dynamic_types": [
  89   // X86-CHECK-SUPPRESSED-NEXT: { "region": "SymRegion{reg_$0<const Shape & S>}", "dyn_type": "const __attribute__((address_space(3))) class clang::Circle &", "sub_classable": true }
  90   (void)C;
  91 }
  92 #endif
  93 #if defined(NOT_SUPPRESSED)
  94 void evalReferences_addrspace(const Shape &S) {
  95   const auto &C = dyn_cast<DEVICE Circle>(S);
  96   // expected-note@-1 {{Assuming 'S' is not a 'const __attribute__((address_space(3))) class clang::Circle &'}}
  97   // expected-note@-2 {{Dereference of null pointer}}
  98   // expected-warning@-3 {{Dereference of null pointer}}
  99   clang_analyzer_printState();
 100   // X86-CHECK: "dynamic_types": [
 101   // X86-CHECK-NEXT: { "region": "SymRegion{reg_$0<const Shape & S>}", "dyn_type": "const __attribute__((address_space(3))) class clang::Circle &", "sub_classable": true }
 102   (void)C;
 103 }
 104 #endif
 105 #elif defined(MIPS)
 106 void evalReferences(const Shape &S) {
 107   const auto &C = dyn_cast<Circle>(S);
 108   // expected-note@-1 {{Assuming 'S' is not a 'const class clang::Circle &'}}
 109   // expected-note@-2 {{Dereference of null pointer}}
 110   // expected-warning@-3 {{Dereference of null pointer}}
 111 }
 112 #if defined(MIPS_SUPPRESSED)
 113 void evalReferences_addrspace(const Shape &S) {
 114   const auto &C = dyn_cast<DEVICE Circle>(S);
 115   (void)C;
 116 }
 117 #endif
 118 #endif
 119
 120 void evalNonNullParamNonNullReturnReference(const Shape &S) {
 121   const auto *C = dyn_cast_or_null<Circle>(S);
 122   // expected-note@-1 {{'C' initialized here}}
 123
 124   if (!dyn_cast_or_null<Circle>(C)) {
 125     // expected-note@-1 {{Assuming 'C' is a 'const class clang::Circle *'}}
 126     // expected-note@-2 {{Taking false branch}}
 127     return;
 128   }
 129
 130   if (dyn_cast_or_null<Triangle>(C)) {
 131     // expected-note@-1 {{Assuming 'C' is not a 'const class clang::Triangle *'}}
 132     // expected-note@-2 {{Taking false branch}}
 133     return;
 134   }
 135
 136   if (dyn_cast_or_null<Rectangle>(C)) {
 137     // expected-note@-1 {{Assuming 'C' is not a 'const class clang::Rectangle *'}}
 138     // expected-note@-2 {{Taking false branch}}
 139     return;
 140   }
 141
 142   if (dyn_cast_or_null<Hexagon>(C)) {
 143     // expected-note@-1 {{Assuming 'C' is not a 'const class clang::Hexagon *'}}
 144     // expected-note@-2 {{Taking false branch}}
 145     return;
 146   }
 147
 148   if (isa<Triangle>(C)) {
 149     // expected-note@-1 {{'C' is not a 'Triangle'}}
 150     // expected-note@-2 {{Taking false branch}}
 151     return;
 152   }
 153
 154   if (isa<Triangle, Rectangle>(C)) {
 155     // expected-note@-1 {{'C' is neither a 'Triangle' nor a 'Rectangle'}}
 156     // expected-note@-2 {{Taking false branch}}
 157     return;
 158   }
 159
 160   if (isa<Triangle, Rectangle, Hexagon>(C)) {
 161     // expected-note@-1 {{'C' is neither a 'Triangle' nor a 'Rectangle' nor a 'Hexagon'}}
 162     // expected-note@-2 {{Taking false branch}}
 163     return;
 164   }
 165
 166   if (isa<Circle, Rectangle, Hexagon>(C)) {
 167     // expected-note@-1 {{'C' is a 'Circle'}}
 168     // expected-note@-2 {{Taking true branch}}
 169
 170     (void)(1 / !C);
 171     // expected-note@-1 {{'C' is non-null}}
 172     // expected-note@-2 {{Division by zero}}
 173     // expected-warning@-3 {{Division by zero}}
 174   }
 175 }
 176
 177 void evalNonNullParamNonNullReturn(const Shape *S) {
 178   const auto *C = cast<Circle>(S);
 179   // expected-note@-1 {{'S' is a 'const class clang::Circle *'}}
 180   // expected-note@-2 {{'C' initialized here}}
 181
 182   if (!dyn_cast_or_null<Circle>(C)) {
 183     // expected-note@-1 {{Assuming 'C' is a 'const class clang::Circle *'}}
 184     // expected-note@-2 {{Taking false branch}}
 185     return;
 186   }
 187
 188   if (dyn_cast_or_null<Triangle>(C)) {
 189     // expected-note@-1 {{Assuming 'C' is not a 'const class clang::Triangle *'}}
 190     // expected-note@-2 {{Taking false branch}}
 191     return;
 192   }
 193
 194   if (dyn_cast_or_null<Rectangle>(C)) {
 195     // expected-note@-1 {{Assuming 'C' is not a 'const class clang::Rectangle *'}}
 196     // expected-note@-2 {{Taking false branch}}
 197     return;
 198   }
 199
 200   if (dyn_cast_or_null<Hexagon>(C)) {
 201     // expected-note@-1 {{Assuming 'C' is not a 'const class clang::Hexagon *'}}
 202     // expected-note@-2 {{Taking false branch}}
 203     return;
 204   }
 205
 206   if (isa<Triangle>(C)) {
 207     // expected-note@-1 {{'C' is not a 'Triangle'}}
 208     // expected-note@-2 {{Taking false branch}}
 209     return;
 210   }
 211
 212   if (isa<Triangle, Rectangle>(C)) {
 213     // expected-note@-1 {{'C' is neither a 'Triangle' nor a 'Rectangle'}}
 214     // expected-note@-2 {{Taking false branch}}
 215     return;
 216   }
 217
 218   if (isa<Triangle, Rectangle, Hexagon>(C)) {
 219     // expected-note@-1 {{'C' is neither a 'Triangle' nor a 'Rectangle' nor a 'Hexagon'}}
 220     // expected-note@-2 {{Taking false branch}}
 221     return;
 222   }
 223
 224   if (isa<Circle, Rectangle, Hexagon>(C)) {
 225     // expected-note@-1 {{'C' is a 'Circle'}}
 226     // expected-note@-2 {{Taking true branch}}
 227
 228     (void)(1 / !C);
 229     // expected-note@-1 {{'C' is non-null}}
 230     // expected-note@-2 {{Division by zero}}
 231     // expected-warning@-3 {{Division by zero}}
 232   }
 233 }
 234
 235 void evalNonNullParamNullReturn(const Shape *S) {
 236   const auto *C = dyn_cast_or_null<Circle>(S);
 237   // expected-note@-1 {{Assuming 'S' is not a 'const class clang::Circle *'}}
 238
 239   if (const auto *T = dyn_cast_or_null<Triangle>(S)) {
 240     // expected-note@-1 {{Assuming 'S' is a 'const class clang::Triangle *'}}
 241     // expected-note@-2 {{'T' initialized here}}
 242     // expected-note@-3 {{'T' is non-null}}
 243     // expected-note@-4 {{Taking true branch}}
 244
 245     (void)(1 / !T);
 246     // expected-note@-1 {{'T' is non-null}}
 247     // expected-note@-2 {{Division by zero}}
 248     // expected-warning@-3 {{Division by zero}}
 249   }
 250 }
 251
 252 void evalNullParamNullReturn(const Shape *S) {
 253   const auto *C = dyn_cast_or_null<Circle>(S);
 254   // expected-note@-1 {{Assuming null pointer is passed into cast}}
 255   // expected-note@-2 {{'C' initialized to a null pointer value}}
 256
 257   (void)(1 / (bool)C);
 258   // expected-note@-1 {{Division by zero}}
 259   // expected-warning@-2 {{Division by zero}}
 260 }
 261
 262 void evalZeroParamNonNullReturnPointer(const Shape *S) {
 263   const auto *C = S->castAs<Circle>();
 264   // expected-note@-1 {{'S' is a 'const class clang::Circle *'}}
 265   // expected-note@-2 {{'C' initialized here}}
 266
 267   (void)(1 / !C);
 268   // expected-note@-1 {{'C' is non-null}}
 269   // expected-note@-2 {{Division by zero}}
 270   // expected-warning@-3 {{Division by zero}}
 271 }
 272
 273 void evalZeroParamNonNullReturn(const Shape &S) {
 274   const auto *C = S.castAs<Circle>();
 275   // expected-note@-1 {{'C' initialized here}}
 276
 277   (void)(1 / !C);
 278   // expected-note@-1 {{'C' is non-null}}
 279   // expected-note@-2 {{Division by zero}}
 280   // expected-warning@-3 {{Division by zero}}
 281 }
 282
 283 void evalZeroParamNullReturn(const Shape *S) {
 284   const auto &C = S->getAs<Circle>();
 285   // expected-note@-1 {{Assuming 'S' is not a 'const class clang::Circle *'}}
 286   // expected-note@-2 {{Storing null pointer value}}
 287   // expected-note@-3 {{'C' initialized here}}
 288
 289   if (!dyn_cast_or_null<Triangle>(S)) {
 290     // expected-note@-1 {{Assuming 'S' is a 'const class clang::Triangle *'}}
 291     // expected-note@-2 {{Taking false branch}}
 292     return;
 293   }
 294
 295   if (!dyn_cast_or_null<Triangle>(S)) {
 296     // expected-note@-1 {{'S' is a 'Triangle'}}
 297     // expected-note@-2 {{Taking false branch}}
 298     return;
 299   }
 300
 301   (void)(1 / (bool)C);
 302   // expected-note@-1 {{Division by zero}}
 303   // expected-warning@-2 {{Division by zero}}
 304 }
 305
 306 // don't crash
 307 // CastValueChecker was using QualType()->getPointeeCXXRecordDecl(), in
 308 // getNoteTag which evaluated to nullptr, then crashed when attempting to
 309 // deref an invocation to getNameAsString(). The fix is to use
 310 // QualType().getAsString().
 311 //
 312 // Example:
 313 // std::string CastToName =
 314 //       CastInfo ? CastInfo->to()->getAsCXXRecordDecl()->getNameAsString()
 315 //                : CastToTy->getPointeeCXXRecordDecl()->getNameAsString();
 316 // Changed to:
 317 // std::string CastToName =
 318 //       CastInfo ? CastInfo->to()->getAsCXXRecordDecl()->getNameAsString()
 319 //                : CastToTy.getAsString();
 320 namespace llvm {
 321 template <typename, typename a> void isa(a &);
 322 template <typename> class PointerUnion {
 323 public:
 324   template <typename T> T *getAs() {
 325     (void)isa<int>(*this);
 326     return nullptr;
 327   }
 328 };
 329 class LLVMContext {
 330   PointerUnion<LLVMContext> c;
 331   void d() { c.getAs<int>(); }
 332 };
 333 } // namespace llvm