unittests/Support/ValueHandleTest.cpp

   1 //===- llvm/unittest/Support/ValueHandleTest.cpp - ValueHandle tests --------===//
   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 #include "llvm/Support/ValueHandle.h"
  11
  12 #include "llvm/Constants.h"
  13 #include "llvm/Instructions.h"
  14 #include "llvm/LLVMContext.h"
  15 #include "llvm/ADT/OwningPtr.h"
  16
  17 #include "gtest/gtest.h"
  18
  19 #include <memory>
  20
  21 using namespace llvm;
  22
  23 namespace {
  24
  25 class ValueHandle : public testing::Test {
  26 protected:
  27   Constant *ConstantV;
  28   std::auto_ptr<BitCastInst> BitcastV;
  29
  30   ValueHandle() :
  31     ConstantV(ConstantInt::get(Type::getInt32Ty(getGlobalContext()), 0)),
  32     BitcastV(new BitCastInst(ConstantV, Type::getInt32Ty(getGlobalContext()))) {
  33   }
  34 };
  35
  36 class ConcreteCallbackVH : public CallbackVH {
  37 public:
  38   ConcreteCallbackVH(Value *V) : CallbackVH(V) {}
  39 };
  40
  41 TEST_F(ValueHandle, WeakVH_BasicOperation) {
  42   WeakVH WVH(BitcastV.get());
  43   EXPECT_EQ(BitcastV.get(), WVH);
  44   WVH = ConstantV;
  45   EXPECT_EQ(ConstantV, WVH);
  46
  47   // Make sure I can call a method on the underlying Value.  It
  48   // doesn't matter which method.
  49   EXPECT_EQ(Type::getInt32Ty(getGlobalContext()), WVH->getType());
  50   EXPECT_EQ(Type::getInt32Ty(getGlobalContext()), (*WVH).getType());
  51 }
  52
  53 TEST_F(ValueHandle, WeakVH_Comparisons) {
  54   WeakVH BitcastWVH(BitcastV.get());
  55   WeakVH ConstantWVH(ConstantV);
  56
  57   EXPECT_TRUE(BitcastWVH == BitcastWVH);
  58   EXPECT_TRUE(BitcastV.get() == BitcastWVH);
  59   EXPECT_TRUE(BitcastWVH == BitcastV.get());
  60   EXPECT_FALSE(BitcastWVH == ConstantWVH);
  61
  62   EXPECT_TRUE(BitcastWVH != ConstantWVH);
  63   EXPECT_TRUE(BitcastV.get() != ConstantWVH);
  64   EXPECT_TRUE(BitcastWVH != ConstantV);
  65   EXPECT_FALSE(BitcastWVH != BitcastWVH);
  66
  67   // Cast to Value* so comparisons work.
  68   Value *BV = BitcastV.get();
  69   Value *CV = ConstantV;
  70   EXPECT_EQ(BV < CV, BitcastWVH < ConstantWVH);
  71   EXPECT_EQ(BV <= CV, BitcastWVH <= ConstantWVH);
  72   EXPECT_EQ(BV > CV, BitcastWVH > ConstantWVH);
  73   EXPECT_EQ(BV >= CV, BitcastWVH >= ConstantWVH);
  74
  75   EXPECT_EQ(BV < CV, BitcastV.get() < ConstantWVH);
  76   EXPECT_EQ(BV <= CV, BitcastV.get() <= ConstantWVH);
  77   EXPECT_EQ(BV > CV, BitcastV.get() > ConstantWVH);
  78   EXPECT_EQ(BV >= CV, BitcastV.get() >= ConstantWVH);
  79
  80   EXPECT_EQ(BV < CV, BitcastWVH < ConstantV);
  81   EXPECT_EQ(BV <= CV, BitcastWVH <= ConstantV);
  82   EXPECT_EQ(BV > CV, BitcastWVH > ConstantV);
  83   EXPECT_EQ(BV >= CV, BitcastWVH >= ConstantV);
  84 }
  85
  86 TEST_F(ValueHandle, WeakVH_FollowsRAUW) {
  87   WeakVH WVH(BitcastV.get());
  88   WeakVH WVH_Copy(WVH);
  89   WeakVH WVH_Recreated(BitcastV.get());
  90   BitcastV->replaceAllUsesWith(ConstantV);
  91   EXPECT_EQ(ConstantV, WVH);
  92   EXPECT_EQ(ConstantV, WVH_Copy);
  93   EXPECT_EQ(ConstantV, WVH_Recreated);
  94 }
  95
  96 TEST_F(ValueHandle, WeakVH_NullOnDeletion) {
  97   WeakVH WVH(BitcastV.get());
  98   WeakVH WVH_Copy(WVH);
  99   WeakVH WVH_Recreated(BitcastV.get());
 100   BitcastV.reset();
 101   Value *null_value = NULL;
 102   EXPECT_EQ(null_value, WVH);
 103   EXPECT_EQ(null_value, WVH_Copy);
 104   EXPECT_EQ(null_value, WVH_Recreated);
 105 }
 106
 107
 108 TEST_F(ValueHandle, AssertingVH_BasicOperation) {
 109   AssertingVH<CastInst> AVH(BitcastV.get());
 110   CastInst *implicit_to_exact_type = AVH;
 111   (void)implicit_to_exact_type;  // Avoid warning.
 112
 113   AssertingVH<Value> GenericAVH(BitcastV.get());
 114   EXPECT_EQ(BitcastV.get(), GenericAVH);
 115   GenericAVH = ConstantV;
 116   EXPECT_EQ(ConstantV, GenericAVH);
 117
 118   // Make sure I can call a method on the underlying CastInst.  It
 119   // doesn't matter which method.
 120   EXPECT_FALSE(AVH->mayWriteToMemory());
 121   EXPECT_FALSE((*AVH).mayWriteToMemory());
 122 }
 123
 124 TEST_F(ValueHandle, AssertingVH_Const) {
 125   const CastInst *ConstBitcast = BitcastV.get();
 126   AssertingVH<const CastInst> AVH(ConstBitcast);
 127   const CastInst *implicit_to_exact_type = AVH;
 128   (void)implicit_to_exact_type;  // Avoid warning.
 129 }
 130
 131 TEST_F(ValueHandle, AssertingVH_Comparisons) {
 132   AssertingVH<Value> BitcastAVH(BitcastV.get());
 133   AssertingVH<Value> ConstantAVH(ConstantV);
 134
 135   EXPECT_TRUE(BitcastAVH == BitcastAVH);
 136   EXPECT_TRUE(BitcastV.get() == BitcastAVH);
 137   EXPECT_TRUE(BitcastAVH == BitcastV.get());
 138   EXPECT_FALSE(BitcastAVH == ConstantAVH);
 139
 140   EXPECT_TRUE(BitcastAVH != ConstantAVH);
 141   EXPECT_TRUE(BitcastV.get() != ConstantAVH);
 142   EXPECT_TRUE(BitcastAVH != ConstantV);
 143   EXPECT_FALSE(BitcastAVH != BitcastAVH);
 144
 145   // Cast to Value* so comparisons work.
 146   Value *BV = BitcastV.get();
 147   Value *CV = ConstantV;
 148   EXPECT_EQ(BV < CV, BitcastAVH < ConstantAVH);
 149   EXPECT_EQ(BV <= CV, BitcastAVH <= ConstantAVH);
 150   EXPECT_EQ(BV > CV, BitcastAVH > ConstantAVH);
 151   EXPECT_EQ(BV >= CV, BitcastAVH >= ConstantAVH);
 152
 153   EXPECT_EQ(BV < CV, BitcastV.get() < ConstantAVH);
 154   EXPECT_EQ(BV <= CV, BitcastV.get() <= ConstantAVH);
 155   EXPECT_EQ(BV > CV, BitcastV.get() > ConstantAVH);
 156   EXPECT_EQ(BV >= CV, BitcastV.get() >= ConstantAVH);
 157
 158   EXPECT_EQ(BV < CV, BitcastAVH < ConstantV);
 159   EXPECT_EQ(BV <= CV, BitcastAVH <= ConstantV);
 160   EXPECT_EQ(BV > CV, BitcastAVH > ConstantV);
 161   EXPECT_EQ(BV >= CV, BitcastAVH >= ConstantV);
 162 }
 163
 164 TEST_F(ValueHandle, AssertingVH_DoesNotFollowRAUW) {
 165   AssertingVH<Value> AVH(BitcastV.get());
 166   BitcastV->replaceAllUsesWith(ConstantV);
 167   EXPECT_EQ(BitcastV.get(), AVH);
 168 }
 169
 170 #ifdef NDEBUG
 171
 172 TEST_F(ValueHandle, AssertingVH_ReducesToPointer) {
 173   EXPECT_EQ(sizeof(CastInst *), sizeof(AssertingVH<CastInst>));
 174 }
 175
 176 #else  // !NDEBUG
 177
 178 #ifdef GTEST_HAS_DEATH_TEST
 179
 180 TEST_F(ValueHandle, AssertingVH_Asserts) {
 181   AssertingVH<Value> AVH(BitcastV.get());
 182   EXPECT_DEATH({BitcastV.reset();},
 183                "An asserting value handle still pointed to this value!");
 184   AssertingVH<Value> Copy(AVH);
 185   AVH = NULL;
 186   EXPECT_DEATH({BitcastV.reset();},
 187                "An asserting value handle still pointed to this value!");
 188   Copy = NULL;
 189   BitcastV.reset();
 190 }
 191
 192 #endif  // GTEST_HAS_DEATH_TEST
 193
 194 #endif  // NDEBUG
 195
 196 TEST_F(ValueHandle, CallbackVH_BasicOperation) {
 197   ConcreteCallbackVH CVH(BitcastV.get());
 198   EXPECT_EQ(BitcastV.get(), CVH);
 199   CVH = ConstantV;
 200   EXPECT_EQ(ConstantV, CVH);
 201
 202   // Make sure I can call a method on the underlying Value.  It
 203   // doesn't matter which method.
 204   EXPECT_EQ(Type::getInt32Ty(getGlobalContext()), CVH->getType());
 205   EXPECT_EQ(Type::getInt32Ty(getGlobalContext()), (*CVH).getType());
 206 }
 207
 208 TEST_F(ValueHandle, CallbackVH_Comparisons) {
 209   ConcreteCallbackVH BitcastCVH(BitcastV.get());
 210   ConcreteCallbackVH ConstantCVH(ConstantV);
 211
 212   EXPECT_TRUE(BitcastCVH == BitcastCVH);
 213   EXPECT_TRUE(BitcastV.get() == BitcastCVH);
 214   EXPECT_TRUE(BitcastCVH == BitcastV.get());
 215   EXPECT_FALSE(BitcastCVH == ConstantCVH);
 216
 217   EXPECT_TRUE(BitcastCVH != ConstantCVH);
 218   EXPECT_TRUE(BitcastV.get() != ConstantCVH);
 219   EXPECT_TRUE(BitcastCVH != ConstantV);
 220   EXPECT_FALSE(BitcastCVH != BitcastCVH);
 221
 222   // Cast to Value* so comparisons work.
 223   Value *BV = BitcastV.get();
 224   Value *CV = ConstantV;
 225   EXPECT_EQ(BV < CV, BitcastCVH < ConstantCVH);
 226   EXPECT_EQ(BV <= CV, BitcastCVH <= ConstantCVH);
 227   EXPECT_EQ(BV > CV, BitcastCVH > ConstantCVH);
 228   EXPECT_EQ(BV >= CV, BitcastCVH >= ConstantCVH);
 229
 230   EXPECT_EQ(BV < CV, BitcastV.get() < ConstantCVH);
 231   EXPECT_EQ(BV <= CV, BitcastV.get() <= ConstantCVH);
 232   EXPECT_EQ(BV > CV, BitcastV.get() > ConstantCVH);
 233   EXPECT_EQ(BV >= CV, BitcastV.get() >= ConstantCVH);
 234
 235   EXPECT_EQ(BV < CV, BitcastCVH < ConstantV);
 236   EXPECT_EQ(BV <= CV, BitcastCVH <= ConstantV);
 237   EXPECT_EQ(BV > CV, BitcastCVH > ConstantV);
 238   EXPECT_EQ(BV >= CV, BitcastCVH >= ConstantV);
 239 }
 240
 241 TEST_F(ValueHandle, CallbackVH_CallbackOnDeletion) {
 242   class RecordingVH : public CallbackVH {
 243   public:
 244     int DeletedCalls;
 245     int AURWCalls;
 246
 247     RecordingVH() : DeletedCalls(0), AURWCalls(0) {}
 248     RecordingVH(Value *V) : CallbackVH(V), DeletedCalls(0), AURWCalls(0) {}
 249
 250   private:
 251     virtual void deleted() { DeletedCalls++; CallbackVH::deleted(); }
 252     virtual void allUsesReplacedWith(Value *) { AURWCalls++; }
 253   };
 254
 255   RecordingVH RVH;
 256   RVH = BitcastV.get();
 257   EXPECT_EQ(0, RVH.DeletedCalls);
 258   EXPECT_EQ(0, RVH.AURWCalls);
 259   BitcastV.reset();
 260   EXPECT_EQ(1, RVH.DeletedCalls);
 261   EXPECT_EQ(0, RVH.AURWCalls);
 262 }
 263
 264 TEST_F(ValueHandle, CallbackVH_CallbackOnRAUW) {
 265   class RecordingVH : public CallbackVH {
 266   public:
 267     int DeletedCalls;
 268     Value *AURWArgument;
 269
 270     RecordingVH() : DeletedCalls(0), AURWArgument(NULL) {}
 271     RecordingVH(Value *V)
 272       : CallbackVH(V), DeletedCalls(0), AURWArgument(NULL) {}
 273
 274   private:
 275     virtual void deleted() { DeletedCalls++; CallbackVH::deleted(); }
 276     virtual void allUsesReplacedWith(Value *new_value) {
 277       EXPECT_EQ(NULL, AURWArgument);
 278       AURWArgument = new_value;
 279     }
 280   };
 281
 282   RecordingVH RVH;
 283   RVH = BitcastV.get();
 284   EXPECT_EQ(0, RVH.DeletedCalls);
 285   EXPECT_EQ(NULL, RVH.AURWArgument);
 286   BitcastV->replaceAllUsesWith(ConstantV);
 287   EXPECT_EQ(0, RVH.DeletedCalls);
 288   EXPECT_EQ(ConstantV, RVH.AURWArgument);
 289 }
 290
 291 TEST_F(ValueHandle, CallbackVH_DeletionCanRAUW) {
 292   class RecoveringVH : public CallbackVH {
 293   public:
 294     int DeletedCalls;
 295     Value *AURWArgument;
 296     LLVMContext *Context;
 297
 298     RecoveringVH() : DeletedCalls(0), AURWArgument(NULL),
 299                      Context(&getGlobalContext()) {}
 300     RecoveringVH(Value *V)
 301       : CallbackVH(V), DeletedCalls(0), AURWArgument(NULL),
 302         Context(&getGlobalContext()) {}
 303
 304   private:
 305     virtual void deleted() {
 306       getValPtr()->replaceAllUsesWith(Constant::getNullValue(Type::getInt32Ty(getGlobalContext())));
 307       setValPtr(NULL);
 308     }
 309     virtual void allUsesReplacedWith(Value *new_value) {
 310       ASSERT_TRUE(NULL != getValPtr());
 311       EXPECT_EQ(1U, getValPtr()->getNumUses());
 312       EXPECT_EQ(NULL, AURWArgument);
 313       AURWArgument = new_value;
 314     }
 315   };
 316
 317   // Normally, if a value has uses, deleting it will crash.  However, we can use
 318   // a CallbackVH to remove the uses before the check for no uses.
 319   RecoveringVH RVH;
 320   RVH = BitcastV.get();
 321   std::auto_ptr<BinaryOperator> BitcastUser(
 322     BinaryOperator::CreateAdd(RVH,
 323                               Constant::getNullValue(Type::getInt32Ty(getGlobalContext()))));
 324   EXPECT_EQ(BitcastV.get(), BitcastUser->getOperand(0));
 325   BitcastV.reset();  // Would crash without the ValueHandler.
 326   EXPECT_EQ(Constant::getNullValue(Type::getInt32Ty(getGlobalContext())), RVH.AURWArgument);
 327   EXPECT_EQ(Constant::getNullValue(Type::getInt32Ty(getGlobalContext())),
 328             BitcastUser->getOperand(0));
 329 }
 330
 331 TEST_F(ValueHandle, DestroyingOtherVHOnSameValueDoesntBreakIteration) {
 332   // When a CallbackVH modifies other ValueHandles in its callbacks,
 333   // that shouldn't interfere with non-modified ValueHandles receiving
 334   // their appropriate callbacks.
 335   //
 336   // We create the active CallbackVH in the middle of a palindromic
 337   // arrangement of other VHs so that the bad behavior would be
 338   // triggered in whichever order callbacks run.
 339
 340   class DestroyingVH : public CallbackVH {
 341   public:
 342     OwningPtr<WeakVH> ToClear[2];
 343     DestroyingVH(Value *V) {
 344       ToClear[0].reset(new WeakVH(V));
 345       setValPtr(V);
 346       ToClear[1].reset(new WeakVH(V));
 347     }
 348     virtual void deleted() {
 349       ToClear[0].reset();
 350       ToClear[1].reset();
 351       CallbackVH::deleted();
 352     }
 353     virtual void allUsesReplacedWith(Value *) {
 354       ToClear[0].reset();
 355       ToClear[1].reset();
 356     }
 357   };
 358
 359   {
 360     WeakVH ShouldBeVisited1(BitcastV.get());
 361     DestroyingVH C(BitcastV.get());
 362     WeakVH ShouldBeVisited2(BitcastV.get());
 363
 364     BitcastV->replaceAllUsesWith(ConstantV);
 365     EXPECT_EQ(ConstantV, static_cast<Value*>(ShouldBeVisited1));
 366     EXPECT_EQ(ConstantV, static_cast<Value*>(ShouldBeVisited2));
 367   }
 368
 369   {
 370     WeakVH ShouldBeVisited1(BitcastV.get());
 371     DestroyingVH C(BitcastV.get());
 372     WeakVH ShouldBeVisited2(BitcastV.get());
 373
 374     BitcastV.reset();
 375     EXPECT_EQ(NULL, static_cast<Value*>(ShouldBeVisited1));
 376     EXPECT_EQ(NULL, static_cast<Value*>(ShouldBeVisited2));
 377   }
 378 }
 379
 380 TEST_F(ValueHandle, AssertingVHCheckedLast) {
 381   // If a CallbackVH exists to clear out a group of AssertingVHs on
 382   // Value deletion, the CallbackVH should get a chance to do so
 383   // before the AssertingVHs assert.
 384
 385   class ClearingVH : public CallbackVH {
 386   public:
 387     AssertingVH<Value> *ToClear[2];
 388     ClearingVH(Value *V,
 389                AssertingVH<Value> &A0, AssertingVH<Value> &A1)
 390       : CallbackVH(V) {
 391       ToClear[0] = &A0;
 392       ToClear[1] = &A1;
 393     }
 394
 395     virtual void deleted() {
 396       *ToClear[0] = 0;
 397       *ToClear[1] = 0;
 398       CallbackVH::deleted();
 399     }
 400   };
 401
 402   AssertingVH<Value> A1, A2;
 403   A1 = BitcastV.get();
 404   ClearingVH C(BitcastV.get(), A1, A2);
 405   A2 = BitcastV.get();
 406   // C.deleted() should run first, clearing the two AssertingVHs,
 407   // which should prevent them from asserting.
 408   BitcastV.reset();
 409 }
 410
 411 }