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1 //===- llvm/unittest/IR/InstructionsTest.cpp - Instructions unit 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/AsmParser/Parser.h"
11 #include "llvm/IR/Instructions.h"
12 #include "llvm/ADT/STLExtras.h"
13 #include "llvm/Analysis/ValueTracking.h"
14 #include "llvm/IR/BasicBlock.h"
15 #include "llvm/IR/Constants.h"
16 #include "llvm/IR/DataLayout.h"
17 #include "llvm/IR/DerivedTypes.h"
18 #include "llvm/IR/Function.h"
19 #include "llvm/IR/IRBuilder.h"
20 #include "llvm/IR/LLVMContext.h"
21 #include "llvm/IR/MDBuilder.h"
22 #include "llvm/IR/Module.h"
23 #include "llvm/IR/NoFolder.h"
24 #include "llvm/IR/Operator.h"
25 #include "llvm/Support/SourceMgr.h"
26 #include "gmock/gmock-matchers.h"
27 #include "gtest/gtest.h"
28 #include <memory>
29 
30 namespace llvm {
31 namespace {
32 
parseIR(LLVMContext & C,const char * IR)33 static std::unique_ptr<Module> parseIR(LLVMContext &C, const char *IR) {
34   SMDiagnostic Err;
35   std::unique_ptr<Module> Mod = parseAssemblyString(IR, Err, C);
36   if (!Mod)
37     Err.print("InstructionsTests", errs());
38   return Mod;
39 }
40 
TEST(InstructionsTest,ReturnInst)41 TEST(InstructionsTest, ReturnInst) {
42   LLVMContext C;
43 
44   // test for PR6589
45   const ReturnInst* r0 = ReturnInst::Create(C);
46   EXPECT_EQ(r0->getNumOperands(), 0U);
47   EXPECT_EQ(r0->op_begin(), r0->op_end());
48 
49   IntegerType* Int1 = IntegerType::get(C, 1);
50   Constant* One = ConstantInt::get(Int1, 1, true);
51   const ReturnInst* r1 = ReturnInst::Create(C, One);
52   EXPECT_EQ(1U, r1->getNumOperands());
53   User::const_op_iterator b(r1->op_begin());
54   EXPECT_NE(r1->op_end(), b);
55   EXPECT_EQ(One, *b);
56   EXPECT_EQ(One, r1->getOperand(0));
57   ++b;
58   EXPECT_EQ(r1->op_end(), b);
59 
60   // clean up
61   delete r0;
62   delete r1;
63 }
64 
65 // Test fixture that provides a module and a single function within it. Useful
66 // for tests that need to refer to the function in some way.
67 class ModuleWithFunctionTest : public testing::Test {
68 protected:
ModuleWithFunctionTest()69   ModuleWithFunctionTest() : M(new Module("MyModule", Ctx)) {
70     FArgTypes.push_back(Type::getInt8Ty(Ctx));
71     FArgTypes.push_back(Type::getInt32Ty(Ctx));
72     FArgTypes.push_back(Type::getInt64Ty(Ctx));
73     FunctionType *FTy =
74         FunctionType::get(Type::getVoidTy(Ctx), FArgTypes, false);
75     F = Function::Create(FTy, Function::ExternalLinkage, "", M.get());
76   }
77 
78   LLVMContext Ctx;
79   std::unique_ptr<Module> M;
80   SmallVector<Type *, 3> FArgTypes;
81   Function *F;
82 };
83 
TEST_F(ModuleWithFunctionTest,CallInst)84 TEST_F(ModuleWithFunctionTest, CallInst) {
85   Value *Args[] = {ConstantInt::get(Type::getInt8Ty(Ctx), 20),
86                    ConstantInt::get(Type::getInt32Ty(Ctx), 9999),
87                    ConstantInt::get(Type::getInt64Ty(Ctx), 42)};
88   std::unique_ptr<CallInst> Call(CallInst::Create(F, Args));
89 
90   // Make sure iteration over a call's arguments works as expected.
91   unsigned Idx = 0;
92   for (Value *Arg : Call->arg_operands()) {
93     EXPECT_EQ(FArgTypes[Idx], Arg->getType());
94     EXPECT_EQ(Call->getArgOperand(Idx)->getType(), Arg->getType());
95     Idx++;
96   }
97 }
98 
TEST_F(ModuleWithFunctionTest,InvokeInst)99 TEST_F(ModuleWithFunctionTest, InvokeInst) {
100   BasicBlock *BB1 = BasicBlock::Create(Ctx, "", F);
101   BasicBlock *BB2 = BasicBlock::Create(Ctx, "", F);
102 
103   Value *Args[] = {ConstantInt::get(Type::getInt8Ty(Ctx), 20),
104                    ConstantInt::get(Type::getInt32Ty(Ctx), 9999),
105                    ConstantInt::get(Type::getInt64Ty(Ctx), 42)};
106   std::unique_ptr<InvokeInst> Invoke(InvokeInst::Create(F, BB1, BB2, Args));
107 
108   // Make sure iteration over invoke's arguments works as expected.
109   unsigned Idx = 0;
110   for (Value *Arg : Invoke->arg_operands()) {
111     EXPECT_EQ(FArgTypes[Idx], Arg->getType());
112     EXPECT_EQ(Invoke->getArgOperand(Idx)->getType(), Arg->getType());
113     Idx++;
114   }
115 }
116 
TEST(InstructionsTest,BranchInst)117 TEST(InstructionsTest, BranchInst) {
118   LLVMContext C;
119 
120   // Make a BasicBlocks
121   BasicBlock* bb0 = BasicBlock::Create(C);
122   BasicBlock* bb1 = BasicBlock::Create(C);
123 
124   // Mandatory BranchInst
125   const BranchInst* b0 = BranchInst::Create(bb0);
126 
127   EXPECT_TRUE(b0->isUnconditional());
128   EXPECT_FALSE(b0->isConditional());
129   EXPECT_EQ(1U, b0->getNumSuccessors());
130 
131   // check num operands
132   EXPECT_EQ(1U, b0->getNumOperands());
133 
134   EXPECT_NE(b0->op_begin(), b0->op_end());
135   EXPECT_EQ(b0->op_end(), std::next(b0->op_begin()));
136 
137   EXPECT_EQ(b0->op_end(), std::next(b0->op_begin()));
138 
139   IntegerType* Int1 = IntegerType::get(C, 1);
140   Constant* One = ConstantInt::get(Int1, 1, true);
141 
142   // Conditional BranchInst
143   BranchInst* b1 = BranchInst::Create(bb0, bb1, One);
144 
145   EXPECT_FALSE(b1->isUnconditional());
146   EXPECT_TRUE(b1->isConditional());
147   EXPECT_EQ(2U, b1->getNumSuccessors());
148 
149   // check num operands
150   EXPECT_EQ(3U, b1->getNumOperands());
151 
152   User::const_op_iterator b(b1->op_begin());
153 
154   // check COND
155   EXPECT_NE(b, b1->op_end());
156   EXPECT_EQ(One, *b);
157   EXPECT_EQ(One, b1->getOperand(0));
158   EXPECT_EQ(One, b1->getCondition());
159   ++b;
160 
161   // check ELSE
162   EXPECT_EQ(bb1, *b);
163   EXPECT_EQ(bb1, b1->getOperand(1));
164   EXPECT_EQ(bb1, b1->getSuccessor(1));
165   ++b;
166 
167   // check THEN
168   EXPECT_EQ(bb0, *b);
169   EXPECT_EQ(bb0, b1->getOperand(2));
170   EXPECT_EQ(bb0, b1->getSuccessor(0));
171   ++b;
172 
173   EXPECT_EQ(b1->op_end(), b);
174 
175   // clean up
176   delete b0;
177   delete b1;
178 
179   delete bb0;
180   delete bb1;
181 }
182 
TEST(InstructionsTest,CastInst)183 TEST(InstructionsTest, CastInst) {
184   LLVMContext C;
185 
186   Type *Int8Ty = Type::getInt8Ty(C);
187   Type *Int16Ty = Type::getInt16Ty(C);
188   Type *Int32Ty = Type::getInt32Ty(C);
189   Type *Int64Ty = Type::getInt64Ty(C);
190   Type *V8x8Ty = VectorType::get(Int8Ty, 8);
191   Type *V8x64Ty = VectorType::get(Int64Ty, 8);
192   Type *X86MMXTy = Type::getX86_MMXTy(C);
193 
194   Type *HalfTy = Type::getHalfTy(C);
195   Type *FloatTy = Type::getFloatTy(C);
196   Type *DoubleTy = Type::getDoubleTy(C);
197 
198   Type *V2Int32Ty = VectorType::get(Int32Ty, 2);
199   Type *V2Int64Ty = VectorType::get(Int64Ty, 2);
200   Type *V4Int16Ty = VectorType::get(Int16Ty, 4);
201 
202   Type *Int32PtrTy = PointerType::get(Int32Ty, 0);
203   Type *Int64PtrTy = PointerType::get(Int64Ty, 0);
204 
205   Type *Int32PtrAS1Ty = PointerType::get(Int32Ty, 1);
206   Type *Int64PtrAS1Ty = PointerType::get(Int64Ty, 1);
207 
208   Type *V2Int32PtrAS1Ty = VectorType::get(Int32PtrAS1Ty, 2);
209   Type *V2Int64PtrAS1Ty = VectorType::get(Int64PtrAS1Ty, 2);
210   Type *V4Int32PtrAS1Ty = VectorType::get(Int32PtrAS1Ty, 4);
211   Type *V4Int64PtrAS1Ty = VectorType::get(Int64PtrAS1Ty, 4);
212 
213   Type *V2Int64PtrTy = VectorType::get(Int64PtrTy, 2);
214   Type *V2Int32PtrTy = VectorType::get(Int32PtrTy, 2);
215   Type *V4Int32PtrTy = VectorType::get(Int32PtrTy, 4);
216 
217   const Constant* c8 = Constant::getNullValue(V8x8Ty);
218   const Constant* c64 = Constant::getNullValue(V8x64Ty);
219 
220   const Constant *v2ptr32 = Constant::getNullValue(V2Int32PtrTy);
221 
222   EXPECT_TRUE(CastInst::isCastable(V8x8Ty, X86MMXTy));
223   EXPECT_TRUE(CastInst::isCastable(X86MMXTy, V8x8Ty));
224   EXPECT_FALSE(CastInst::isCastable(Int64Ty, X86MMXTy));
225   EXPECT_TRUE(CastInst::isCastable(V8x64Ty, V8x8Ty));
226   EXPECT_TRUE(CastInst::isCastable(V8x8Ty, V8x64Ty));
227   EXPECT_EQ(CastInst::Trunc, CastInst::getCastOpcode(c64, true, V8x8Ty, true));
228   EXPECT_EQ(CastInst::SExt, CastInst::getCastOpcode(c8, true, V8x64Ty, true));
229 
230   EXPECT_FALSE(CastInst::isBitCastable(V8x8Ty, X86MMXTy));
231   EXPECT_FALSE(CastInst::isBitCastable(X86MMXTy, V8x8Ty));
232   EXPECT_FALSE(CastInst::isBitCastable(Int64Ty, X86MMXTy));
233   EXPECT_FALSE(CastInst::isBitCastable(V8x64Ty, V8x8Ty));
234   EXPECT_FALSE(CastInst::isBitCastable(V8x8Ty, V8x64Ty));
235 
236   // Check address space casts are rejected since we don't know the sizes here
237   EXPECT_FALSE(CastInst::isBitCastable(Int32PtrTy, Int32PtrAS1Ty));
238   EXPECT_FALSE(CastInst::isBitCastable(Int32PtrAS1Ty, Int32PtrTy));
239   EXPECT_FALSE(CastInst::isBitCastable(V2Int32PtrTy, V2Int32PtrAS1Ty));
240   EXPECT_FALSE(CastInst::isBitCastable(V2Int32PtrAS1Ty, V2Int32PtrTy));
241   EXPECT_TRUE(CastInst::isBitCastable(V2Int32PtrAS1Ty, V2Int64PtrAS1Ty));
242   EXPECT_TRUE(CastInst::isCastable(V2Int32PtrAS1Ty, V2Int32PtrTy));
243   EXPECT_EQ(CastInst::AddrSpaceCast, CastInst::getCastOpcode(v2ptr32, true,
244                                                              V2Int32PtrAS1Ty,
245                                                              true));
246 
247   // Test mismatched number of elements for pointers
248   EXPECT_FALSE(CastInst::isBitCastable(V2Int32PtrAS1Ty, V4Int64PtrAS1Ty));
249   EXPECT_FALSE(CastInst::isBitCastable(V4Int64PtrAS1Ty, V2Int32PtrAS1Ty));
250   EXPECT_FALSE(CastInst::isBitCastable(V2Int32PtrAS1Ty, V4Int32PtrAS1Ty));
251   EXPECT_FALSE(CastInst::isBitCastable(Int32PtrTy, V2Int32PtrTy));
252   EXPECT_FALSE(CastInst::isBitCastable(V2Int32PtrTy, Int32PtrTy));
253 
254   EXPECT_TRUE(CastInst::isBitCastable(Int32PtrTy, Int64PtrTy));
255   EXPECT_FALSE(CastInst::isBitCastable(DoubleTy, FloatTy));
256   EXPECT_FALSE(CastInst::isBitCastable(FloatTy, DoubleTy));
257   EXPECT_TRUE(CastInst::isBitCastable(FloatTy, FloatTy));
258   EXPECT_TRUE(CastInst::isBitCastable(FloatTy, FloatTy));
259   EXPECT_TRUE(CastInst::isBitCastable(FloatTy, Int32Ty));
260   EXPECT_TRUE(CastInst::isBitCastable(Int16Ty, HalfTy));
261   EXPECT_TRUE(CastInst::isBitCastable(Int32Ty, FloatTy));
262   EXPECT_TRUE(CastInst::isBitCastable(V2Int32Ty, Int64Ty));
263 
264   EXPECT_TRUE(CastInst::isBitCastable(V2Int32Ty, V4Int16Ty));
265   EXPECT_FALSE(CastInst::isBitCastable(Int32Ty, Int64Ty));
266   EXPECT_FALSE(CastInst::isBitCastable(Int64Ty, Int32Ty));
267 
268   EXPECT_FALSE(CastInst::isBitCastable(V2Int32PtrTy, Int64Ty));
269   EXPECT_FALSE(CastInst::isBitCastable(Int64Ty, V2Int32PtrTy));
270   EXPECT_TRUE(CastInst::isBitCastable(V2Int64PtrTy, V2Int32PtrTy));
271   EXPECT_TRUE(CastInst::isBitCastable(V2Int32PtrTy, V2Int64PtrTy));
272   EXPECT_FALSE(CastInst::isBitCastable(V2Int32Ty, V2Int64Ty));
273   EXPECT_FALSE(CastInst::isBitCastable(V2Int64Ty, V2Int32Ty));
274 
275 
276   EXPECT_FALSE(CastInst::castIsValid(Instruction::BitCast,
277                                      Constant::getNullValue(V4Int32PtrTy),
278                                      V2Int32PtrTy));
279   EXPECT_FALSE(CastInst::castIsValid(Instruction::BitCast,
280                                      Constant::getNullValue(V2Int32PtrTy),
281                                      V4Int32PtrTy));
282 
283   EXPECT_FALSE(CastInst::castIsValid(Instruction::AddrSpaceCast,
284                                      Constant::getNullValue(V4Int32PtrAS1Ty),
285                                      V2Int32PtrTy));
286   EXPECT_FALSE(CastInst::castIsValid(Instruction::AddrSpaceCast,
287                                      Constant::getNullValue(V2Int32PtrTy),
288                                      V4Int32PtrAS1Ty));
289 
290 
291   // Check that assertion is not hit when creating a cast with a vector of
292   // pointers
293   // First form
294   BasicBlock *BB = BasicBlock::Create(C);
295   Constant *NullV2I32Ptr = Constant::getNullValue(V2Int32PtrTy);
296   auto Inst1 = CastInst::CreatePointerCast(NullV2I32Ptr, V2Int32Ty, "foo", BB);
297 
298   // Second form
299   auto Inst2 = CastInst::CreatePointerCast(NullV2I32Ptr, V2Int32Ty);
300 
301   delete Inst2;
302   Inst1->eraseFromParent();
303   delete BB;
304 }
305 
TEST(InstructionsTest,VectorGep)306 TEST(InstructionsTest, VectorGep) {
307   LLVMContext C;
308 
309   // Type Definitions
310   Type *I8Ty = IntegerType::get(C, 8);
311   Type *I32Ty = IntegerType::get(C, 32);
312   PointerType *Ptri8Ty = PointerType::get(I8Ty, 0);
313   PointerType *Ptri32Ty = PointerType::get(I32Ty, 0);
314 
315   VectorType *V2xi8PTy = VectorType::get(Ptri8Ty, 2);
316   VectorType *V2xi32PTy = VectorType::get(Ptri32Ty, 2);
317 
318   // Test different aspects of the vector-of-pointers type
319   // and GEPs which use this type.
320   ConstantInt *Ci32a = ConstantInt::get(C, APInt(32, 1492));
321   ConstantInt *Ci32b = ConstantInt::get(C, APInt(32, 1948));
322   std::vector<Constant*> ConstVa(2, Ci32a);
323   std::vector<Constant*> ConstVb(2, Ci32b);
324   Constant *C2xi32a = ConstantVector::get(ConstVa);
325   Constant *C2xi32b = ConstantVector::get(ConstVb);
326 
327   CastInst *PtrVecA = new IntToPtrInst(C2xi32a, V2xi32PTy);
328   CastInst *PtrVecB = new IntToPtrInst(C2xi32b, V2xi32PTy);
329 
330   ICmpInst *ICmp0 = new ICmpInst(ICmpInst::ICMP_SGT, PtrVecA, PtrVecB);
331   ICmpInst *ICmp1 = new ICmpInst(ICmpInst::ICMP_ULT, PtrVecA, PtrVecB);
332   EXPECT_NE(ICmp0, ICmp1); // suppress warning.
333 
334   BasicBlock* BB0 = BasicBlock::Create(C);
335   // Test InsertAtEnd ICmpInst constructor.
336   ICmpInst *ICmp2 = new ICmpInst(*BB0, ICmpInst::ICMP_SGE, PtrVecA, PtrVecB);
337   EXPECT_NE(ICmp0, ICmp2); // suppress warning.
338 
339   GetElementPtrInst *Gep0 = GetElementPtrInst::Create(I32Ty, PtrVecA, C2xi32a);
340   GetElementPtrInst *Gep1 = GetElementPtrInst::Create(I32Ty, PtrVecA, C2xi32b);
341   GetElementPtrInst *Gep2 = GetElementPtrInst::Create(I32Ty, PtrVecB, C2xi32a);
342   GetElementPtrInst *Gep3 = GetElementPtrInst::Create(I32Ty, PtrVecB, C2xi32b);
343 
344   CastInst *BTC0 = new BitCastInst(Gep0, V2xi8PTy);
345   CastInst *BTC1 = new BitCastInst(Gep1, V2xi8PTy);
346   CastInst *BTC2 = new BitCastInst(Gep2, V2xi8PTy);
347   CastInst *BTC3 = new BitCastInst(Gep3, V2xi8PTy);
348 
349   Value *S0 = BTC0->stripPointerCasts();
350   Value *S1 = BTC1->stripPointerCasts();
351   Value *S2 = BTC2->stripPointerCasts();
352   Value *S3 = BTC3->stripPointerCasts();
353 
354   EXPECT_NE(S0, Gep0);
355   EXPECT_NE(S1, Gep1);
356   EXPECT_NE(S2, Gep2);
357   EXPECT_NE(S3, Gep3);
358 
359   int64_t Offset;
360   DataLayout TD("e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f3"
361                 "2:32:32-f64:64:64-v64:64:64-v128:128:128-a:0:64-s:64:64-f80"
362                 ":128:128-n8:16:32:64-S128");
363   // Make sure we don't crash
364   GetPointerBaseWithConstantOffset(Gep0, Offset, TD);
365   GetPointerBaseWithConstantOffset(Gep1, Offset, TD);
366   GetPointerBaseWithConstantOffset(Gep2, Offset, TD);
367   GetPointerBaseWithConstantOffset(Gep3, Offset, TD);
368 
369   // Gep of Geps
370   GetElementPtrInst *GepII0 = GetElementPtrInst::Create(I32Ty, Gep0, C2xi32b);
371   GetElementPtrInst *GepII1 = GetElementPtrInst::Create(I32Ty, Gep1, C2xi32a);
372   GetElementPtrInst *GepII2 = GetElementPtrInst::Create(I32Ty, Gep2, C2xi32b);
373   GetElementPtrInst *GepII3 = GetElementPtrInst::Create(I32Ty, Gep3, C2xi32a);
374 
375   EXPECT_EQ(GepII0->getNumIndices(), 1u);
376   EXPECT_EQ(GepII1->getNumIndices(), 1u);
377   EXPECT_EQ(GepII2->getNumIndices(), 1u);
378   EXPECT_EQ(GepII3->getNumIndices(), 1u);
379 
380   EXPECT_FALSE(GepII0->hasAllZeroIndices());
381   EXPECT_FALSE(GepII1->hasAllZeroIndices());
382   EXPECT_FALSE(GepII2->hasAllZeroIndices());
383   EXPECT_FALSE(GepII3->hasAllZeroIndices());
384 
385   delete GepII0;
386   delete GepII1;
387   delete GepII2;
388   delete GepII3;
389 
390   delete BTC0;
391   delete BTC1;
392   delete BTC2;
393   delete BTC3;
394 
395   delete Gep0;
396   delete Gep1;
397   delete Gep2;
398   delete Gep3;
399 
400   ICmp2->eraseFromParent();
401   delete BB0;
402 
403   delete ICmp0;
404   delete ICmp1;
405   delete PtrVecA;
406   delete PtrVecB;
407 }
408 
TEST(InstructionsTest,FPMathOperator)409 TEST(InstructionsTest, FPMathOperator) {
410   LLVMContext Context;
411   IRBuilder<> Builder(Context);
412   MDBuilder MDHelper(Context);
413   Instruction *I = Builder.CreatePHI(Builder.getDoubleTy(), 0);
414   MDNode *MD1 = MDHelper.createFPMath(1.0);
415   Value *V1 = Builder.CreateFAdd(I, I, "", MD1);
416   EXPECT_TRUE(isa<FPMathOperator>(V1));
417   FPMathOperator *O1 = cast<FPMathOperator>(V1);
418   EXPECT_EQ(O1->getFPAccuracy(), 1.0);
419   V1->deleteValue();
420   I->deleteValue();
421 }
422 
423 
TEST(InstructionsTest,isEliminableCastPair)424 TEST(InstructionsTest, isEliminableCastPair) {
425   LLVMContext C;
426 
427   Type* Int16Ty = Type::getInt16Ty(C);
428   Type* Int32Ty = Type::getInt32Ty(C);
429   Type* Int64Ty = Type::getInt64Ty(C);
430   Type* Int64PtrTy = Type::getInt64PtrTy(C);
431 
432   // Source and destination pointers have same size -> bitcast.
433   EXPECT_EQ(CastInst::isEliminableCastPair(CastInst::PtrToInt,
434                                            CastInst::IntToPtr,
435                                            Int64PtrTy, Int64Ty, Int64PtrTy,
436                                            Int32Ty, nullptr, Int32Ty),
437             CastInst::BitCast);
438 
439   // Source and destination have unknown sizes, but the same address space and
440   // the intermediate int is the maximum pointer size -> bitcast
441   EXPECT_EQ(CastInst::isEliminableCastPair(CastInst::PtrToInt,
442                                            CastInst::IntToPtr,
443                                            Int64PtrTy, Int64Ty, Int64PtrTy,
444                                            nullptr, nullptr, nullptr),
445             CastInst::BitCast);
446 
447   // Source and destination have unknown sizes, but the same address space and
448   // the intermediate int is not the maximum pointer size -> nothing
449   EXPECT_EQ(CastInst::isEliminableCastPair(CastInst::PtrToInt,
450                                            CastInst::IntToPtr,
451                                            Int64PtrTy, Int32Ty, Int64PtrTy,
452                                            nullptr, nullptr, nullptr),
453             0U);
454 
455   // Middle pointer big enough -> bitcast.
456   EXPECT_EQ(CastInst::isEliminableCastPair(CastInst::IntToPtr,
457                                            CastInst::PtrToInt,
458                                            Int64Ty, Int64PtrTy, Int64Ty,
459                                            nullptr, Int64Ty, nullptr),
460             CastInst::BitCast);
461 
462   // Middle pointer too small -> fail.
463   EXPECT_EQ(CastInst::isEliminableCastPair(CastInst::IntToPtr,
464                                            CastInst::PtrToInt,
465                                            Int64Ty, Int64PtrTy, Int64Ty,
466                                            nullptr, Int32Ty, nullptr),
467             0U);
468 
469   // Test that we don't eliminate bitcasts between different address spaces,
470   // or if we don't have available pointer size information.
471   DataLayout DL("e-p:32:32:32-p1:16:16:16-p2:64:64:64-i1:8:8-i8:8:8-i16:16:16"
472                 "-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64"
473                 "-v128:128:128-a:0:64-s:64:64-f80:128:128-n8:16:32:64-S128");
474 
475   Type* Int64PtrTyAS1 = Type::getInt64PtrTy(C, 1);
476   Type* Int64PtrTyAS2 = Type::getInt64PtrTy(C, 2);
477 
478   IntegerType *Int16SizePtr = DL.getIntPtrType(C, 1);
479   IntegerType *Int64SizePtr = DL.getIntPtrType(C, 2);
480 
481   // Cannot simplify inttoptr, addrspacecast
482   EXPECT_EQ(CastInst::isEliminableCastPair(CastInst::IntToPtr,
483                                            CastInst::AddrSpaceCast,
484                                            Int16Ty, Int64PtrTyAS1, Int64PtrTyAS2,
485                                            nullptr, Int16SizePtr, Int64SizePtr),
486             0U);
487 
488   // Cannot simplify addrspacecast, ptrtoint
489   EXPECT_EQ(CastInst::isEliminableCastPair(CastInst::AddrSpaceCast,
490                                            CastInst::PtrToInt,
491                                            Int64PtrTyAS1, Int64PtrTyAS2, Int16Ty,
492                                            Int64SizePtr, Int16SizePtr, nullptr),
493             0U);
494 
495   // Pass since the bitcast address spaces are the same
496   EXPECT_EQ(CastInst::isEliminableCastPair(CastInst::IntToPtr,
497                                            CastInst::BitCast,
498                                            Int16Ty, Int64PtrTyAS1, Int64PtrTyAS1,
499                                            nullptr, nullptr, nullptr),
500             CastInst::IntToPtr);
501 
502 }
503 
TEST(InstructionsTest,CloneCall)504 TEST(InstructionsTest, CloneCall) {
505   LLVMContext C;
506   Type *Int32Ty = Type::getInt32Ty(C);
507   Type *ArgTys[] = {Int32Ty, Int32Ty, Int32Ty};
508   Type *FnTy = FunctionType::get(Int32Ty, ArgTys, /*isVarArg=*/false);
509   Value *Callee = Constant::getNullValue(FnTy->getPointerTo());
510   Value *Args[] = {
511     ConstantInt::get(Int32Ty, 1),
512     ConstantInt::get(Int32Ty, 2),
513     ConstantInt::get(Int32Ty, 3)
514   };
515   std::unique_ptr<CallInst> Call(CallInst::Create(Callee, Args, "result"));
516 
517   // Test cloning the tail call kind.
518   CallInst::TailCallKind Kinds[] = {CallInst::TCK_None, CallInst::TCK_Tail,
519                                     CallInst::TCK_MustTail};
520   for (CallInst::TailCallKind TCK : Kinds) {
521     Call->setTailCallKind(TCK);
522     std::unique_ptr<CallInst> Clone(cast<CallInst>(Call->clone()));
523     EXPECT_EQ(Call->getTailCallKind(), Clone->getTailCallKind());
524   }
525   Call->setTailCallKind(CallInst::TCK_None);
526 
527   // Test cloning an attribute.
528   {
529     AttrBuilder AB;
530     AB.addAttribute(Attribute::ReadOnly);
531     Call->setAttributes(
532         AttributeList::get(C, AttributeList::FunctionIndex, AB));
533     std::unique_ptr<CallInst> Clone(cast<CallInst>(Call->clone()));
534     EXPECT_TRUE(Clone->onlyReadsMemory());
535   }
536 }
537 
TEST(InstructionsTest,AlterCallBundles)538 TEST(InstructionsTest, AlterCallBundles) {
539   LLVMContext C;
540   Type *Int32Ty = Type::getInt32Ty(C);
541   Type *FnTy = FunctionType::get(Int32Ty, Int32Ty, /*isVarArg=*/false);
542   Value *Callee = Constant::getNullValue(FnTy->getPointerTo());
543   Value *Args[] = {ConstantInt::get(Int32Ty, 42)};
544   OperandBundleDef OldBundle("before", UndefValue::get(Int32Ty));
545   std::unique_ptr<CallInst> Call(
546       CallInst::Create(Callee, Args, OldBundle, "result"));
547   Call->setTailCallKind(CallInst::TailCallKind::TCK_NoTail);
548   AttrBuilder AB;
549   AB.addAttribute(Attribute::Cold);
550   Call->setAttributes(AttributeList::get(C, AttributeList::FunctionIndex, AB));
551   Call->setDebugLoc(DebugLoc(MDNode::get(C, None)));
552 
553   OperandBundleDef NewBundle("after", ConstantInt::get(Int32Ty, 7));
554   std::unique_ptr<CallInst> Clone(CallInst::Create(Call.get(), NewBundle));
555   EXPECT_EQ(Call->getNumArgOperands(), Clone->getNumArgOperands());
556   EXPECT_EQ(Call->getArgOperand(0), Clone->getArgOperand(0));
557   EXPECT_EQ(Call->getCallingConv(), Clone->getCallingConv());
558   EXPECT_EQ(Call->getTailCallKind(), Clone->getTailCallKind());
559   EXPECT_TRUE(Clone->hasFnAttr(Attribute::AttrKind::Cold));
560   EXPECT_EQ(Call->getDebugLoc(), Clone->getDebugLoc());
561   EXPECT_EQ(Clone->getNumOperandBundles(), 1U);
562   EXPECT_TRUE(Clone->getOperandBundle("after").hasValue());
563 }
564 
TEST(InstructionsTest,AlterInvokeBundles)565 TEST(InstructionsTest, AlterInvokeBundles) {
566   LLVMContext C;
567   Type *Int32Ty = Type::getInt32Ty(C);
568   Type *FnTy = FunctionType::get(Int32Ty, Int32Ty, /*isVarArg=*/false);
569   Value *Callee = Constant::getNullValue(FnTy->getPointerTo());
570   Value *Args[] = {ConstantInt::get(Int32Ty, 42)};
571   std::unique_ptr<BasicBlock> NormalDest(BasicBlock::Create(C));
572   std::unique_ptr<BasicBlock> UnwindDest(BasicBlock::Create(C));
573   OperandBundleDef OldBundle("before", UndefValue::get(Int32Ty));
574   std::unique_ptr<InvokeInst> Invoke(InvokeInst::Create(
575       Callee, NormalDest.get(), UnwindDest.get(), Args, OldBundle, "result"));
576   AttrBuilder AB;
577   AB.addAttribute(Attribute::Cold);
578   Invoke->setAttributes(
579       AttributeList::get(C, AttributeList::FunctionIndex, AB));
580   Invoke->setDebugLoc(DebugLoc(MDNode::get(C, None)));
581 
582   OperandBundleDef NewBundle("after", ConstantInt::get(Int32Ty, 7));
583   std::unique_ptr<InvokeInst> Clone(
584       InvokeInst::Create(Invoke.get(), NewBundle));
585   EXPECT_EQ(Invoke->getNormalDest(), Clone->getNormalDest());
586   EXPECT_EQ(Invoke->getUnwindDest(), Clone->getUnwindDest());
587   EXPECT_EQ(Invoke->getNumArgOperands(), Clone->getNumArgOperands());
588   EXPECT_EQ(Invoke->getArgOperand(0), Clone->getArgOperand(0));
589   EXPECT_EQ(Invoke->getCallingConv(), Clone->getCallingConv());
590   EXPECT_TRUE(Clone->hasFnAttr(Attribute::AttrKind::Cold));
591   EXPECT_EQ(Invoke->getDebugLoc(), Clone->getDebugLoc());
592   EXPECT_EQ(Clone->getNumOperandBundles(), 1U);
593   EXPECT_TRUE(Clone->getOperandBundle("after").hasValue());
594 }
595 
TEST_F(ModuleWithFunctionTest,DropPoisonGeneratingFlags)596 TEST_F(ModuleWithFunctionTest, DropPoisonGeneratingFlags) {
597   auto *OnlyBB = BasicBlock::Create(Ctx, "bb", F);
598   auto *Arg0 = &*F->arg_begin();
599 
600   IRBuilder<NoFolder> B(Ctx);
601   B.SetInsertPoint(OnlyBB);
602 
603   {
604     auto *UI =
605         cast<Instruction>(B.CreateUDiv(Arg0, Arg0, "", /*isExact*/ true));
606     ASSERT_TRUE(UI->isExact());
607     UI->dropPoisonGeneratingFlags();
608     ASSERT_FALSE(UI->isExact());
609   }
610 
611   {
612     auto *ShrI =
613         cast<Instruction>(B.CreateLShr(Arg0, Arg0, "", /*isExact*/ true));
614     ASSERT_TRUE(ShrI->isExact());
615     ShrI->dropPoisonGeneratingFlags();
616     ASSERT_FALSE(ShrI->isExact());
617   }
618 
619   {
620     auto *AI = cast<Instruction>(
621         B.CreateAdd(Arg0, Arg0, "", /*HasNUW*/ true, /*HasNSW*/ false));
622     ASSERT_TRUE(AI->hasNoUnsignedWrap());
623     AI->dropPoisonGeneratingFlags();
624     ASSERT_FALSE(AI->hasNoUnsignedWrap());
625     ASSERT_FALSE(AI->hasNoSignedWrap());
626   }
627 
628   {
629     auto *SI = cast<Instruction>(
630         B.CreateAdd(Arg0, Arg0, "", /*HasNUW*/ false, /*HasNSW*/ true));
631     ASSERT_TRUE(SI->hasNoSignedWrap());
632     SI->dropPoisonGeneratingFlags();
633     ASSERT_FALSE(SI->hasNoUnsignedWrap());
634     ASSERT_FALSE(SI->hasNoSignedWrap());
635   }
636 
637   {
638     auto *ShlI = cast<Instruction>(
639         B.CreateShl(Arg0, Arg0, "", /*HasNUW*/ true, /*HasNSW*/ true));
640     ASSERT_TRUE(ShlI->hasNoSignedWrap());
641     ASSERT_TRUE(ShlI->hasNoUnsignedWrap());
642     ShlI->dropPoisonGeneratingFlags();
643     ASSERT_FALSE(ShlI->hasNoUnsignedWrap());
644     ASSERT_FALSE(ShlI->hasNoSignedWrap());
645   }
646 
647   {
648     Value *GEPBase = Constant::getNullValue(B.getInt8PtrTy());
649     auto *GI = cast<GetElementPtrInst>(B.CreateInBoundsGEP(GEPBase, {Arg0}));
650     ASSERT_TRUE(GI->isInBounds());
651     GI->dropPoisonGeneratingFlags();
652     ASSERT_FALSE(GI->isInBounds());
653   }
654 }
655 
TEST(InstructionsTest,GEPIndices)656 TEST(InstructionsTest, GEPIndices) {
657   LLVMContext Context;
658   IRBuilder<NoFolder> Builder(Context);
659   Type *ElementTy = Builder.getInt8Ty();
660   Type *ArrTy = ArrayType::get(ArrayType::get(ElementTy, 64), 64);
661   Value *Indices[] = {
662     Builder.getInt32(0),
663     Builder.getInt32(13),
664     Builder.getInt32(42) };
665 
666   Value *V = Builder.CreateGEP(ArrTy, UndefValue::get(PointerType::getUnqual(ArrTy)),
667                                Indices);
668   ASSERT_TRUE(isa<GetElementPtrInst>(V));
669 
670   auto *GEPI = cast<GetElementPtrInst>(V);
671   ASSERT_NE(GEPI->idx_begin(), GEPI->idx_end());
672   ASSERT_EQ(GEPI->idx_end(), std::next(GEPI->idx_begin(), 3));
673   EXPECT_EQ(Indices[0], GEPI->idx_begin()[0]);
674   EXPECT_EQ(Indices[1], GEPI->idx_begin()[1]);
675   EXPECT_EQ(Indices[2], GEPI->idx_begin()[2]);
676   EXPECT_EQ(GEPI->idx_begin(), GEPI->indices().begin());
677   EXPECT_EQ(GEPI->idx_end(), GEPI->indices().end());
678 
679   const auto *CGEPI = GEPI;
680   ASSERT_NE(CGEPI->idx_begin(), CGEPI->idx_end());
681   ASSERT_EQ(CGEPI->idx_end(), std::next(CGEPI->idx_begin(), 3));
682   EXPECT_EQ(Indices[0], CGEPI->idx_begin()[0]);
683   EXPECT_EQ(Indices[1], CGEPI->idx_begin()[1]);
684   EXPECT_EQ(Indices[2], CGEPI->idx_begin()[2]);
685   EXPECT_EQ(CGEPI->idx_begin(), CGEPI->indices().begin());
686   EXPECT_EQ(CGEPI->idx_end(), CGEPI->indices().end());
687 
688   delete GEPI;
689 }
690 
TEST(InstructionsTest,SwitchInst)691 TEST(InstructionsTest, SwitchInst) {
692   LLVMContext C;
693 
694   std::unique_ptr<BasicBlock> BB1, BB2, BB3;
695   BB1.reset(BasicBlock::Create(C));
696   BB2.reset(BasicBlock::Create(C));
697   BB3.reset(BasicBlock::Create(C));
698 
699   // We create block 0 after the others so that it gets destroyed first and
700   // clears the uses of the other basic blocks.
701   std::unique_ptr<BasicBlock> BB0(BasicBlock::Create(C));
702 
703   auto *Int32Ty = Type::getInt32Ty(C);
704 
705   SwitchInst *SI =
706       SwitchInst::Create(UndefValue::get(Int32Ty), BB0.get(), 3, BB0.get());
707   SI->addCase(ConstantInt::get(Int32Ty, 1), BB1.get());
708   SI->addCase(ConstantInt::get(Int32Ty, 2), BB2.get());
709   SI->addCase(ConstantInt::get(Int32Ty, 3), BB3.get());
710 
711   auto CI = SI->case_begin();
712   ASSERT_NE(CI, SI->case_end());
713   EXPECT_EQ(1, CI->getCaseValue()->getSExtValue());
714   EXPECT_EQ(BB1.get(), CI->getCaseSuccessor());
715   EXPECT_EQ(2, (CI + 1)->getCaseValue()->getSExtValue());
716   EXPECT_EQ(BB2.get(), (CI + 1)->getCaseSuccessor());
717   EXPECT_EQ(3, (CI + 2)->getCaseValue()->getSExtValue());
718   EXPECT_EQ(BB3.get(), (CI + 2)->getCaseSuccessor());
719   EXPECT_EQ(CI + 1, std::next(CI));
720   EXPECT_EQ(CI + 2, std::next(CI, 2));
721   EXPECT_EQ(CI + 3, std::next(CI, 3));
722   EXPECT_EQ(SI->case_end(), CI + 3);
723   EXPECT_EQ(0, CI - CI);
724   EXPECT_EQ(1, (CI + 1) - CI);
725   EXPECT_EQ(2, (CI + 2) - CI);
726   EXPECT_EQ(3, SI->case_end() - CI);
727   EXPECT_EQ(3, std::distance(CI, SI->case_end()));
728 
729   auto CCI = const_cast<const SwitchInst *>(SI)->case_begin();
730   SwitchInst::ConstCaseIt CCE = SI->case_end();
731   ASSERT_NE(CCI, SI->case_end());
732   EXPECT_EQ(1, CCI->getCaseValue()->getSExtValue());
733   EXPECT_EQ(BB1.get(), CCI->getCaseSuccessor());
734   EXPECT_EQ(2, (CCI + 1)->getCaseValue()->getSExtValue());
735   EXPECT_EQ(BB2.get(), (CCI + 1)->getCaseSuccessor());
736   EXPECT_EQ(3, (CCI + 2)->getCaseValue()->getSExtValue());
737   EXPECT_EQ(BB3.get(), (CCI + 2)->getCaseSuccessor());
738   EXPECT_EQ(CCI + 1, std::next(CCI));
739   EXPECT_EQ(CCI + 2, std::next(CCI, 2));
740   EXPECT_EQ(CCI + 3, std::next(CCI, 3));
741   EXPECT_EQ(CCE, CCI + 3);
742   EXPECT_EQ(0, CCI - CCI);
743   EXPECT_EQ(1, (CCI + 1) - CCI);
744   EXPECT_EQ(2, (CCI + 2) - CCI);
745   EXPECT_EQ(3, CCE - CCI);
746   EXPECT_EQ(3, std::distance(CCI, CCE));
747 
748   // Make sure that the const iterator is compatible with a const auto ref.
749   const auto &Handle = *CCI;
750   EXPECT_EQ(1, Handle.getCaseValue()->getSExtValue());
751   EXPECT_EQ(BB1.get(), Handle.getCaseSuccessor());
752 }
753 
TEST(InstructionsTest,CommuteShuffleMask)754 TEST(InstructionsTest, CommuteShuffleMask) {
755   SmallVector<int, 16> Indices({-1, 0, 7});
756   ShuffleVectorInst::commuteShuffleMask(Indices, 4);
757   EXPECT_THAT(Indices, testing::ContainerEq(ArrayRef<int>({-1, 4, 3})));
758 }
759 
TEST(InstructionsTest,ShuffleMaskQueries)760 TEST(InstructionsTest, ShuffleMaskQueries) {
761   // Create the elements for various constant vectors.
762   LLVMContext Ctx;
763   Type *Int32Ty = Type::getInt32Ty(Ctx);
764   Constant *CU = UndefValue::get(Int32Ty);
765   Constant *C0 = ConstantInt::get(Int32Ty, 0);
766   Constant *C1 = ConstantInt::get(Int32Ty, 1);
767   Constant *C2 = ConstantInt::get(Int32Ty, 2);
768   Constant *C3 = ConstantInt::get(Int32Ty, 3);
769   Constant *C4 = ConstantInt::get(Int32Ty, 4);
770   Constant *C5 = ConstantInt::get(Int32Ty, 5);
771   Constant *C6 = ConstantInt::get(Int32Ty, 6);
772   Constant *C7 = ConstantInt::get(Int32Ty, 7);
773 
774   Constant *Identity = ConstantVector::get({C0, CU, C2, C3, C4});
775   EXPECT_TRUE(ShuffleVectorInst::isIdentityMask(Identity));
776   EXPECT_FALSE(ShuffleVectorInst::isSelectMask(Identity)); // identity is distinguished from select
777   EXPECT_FALSE(ShuffleVectorInst::isReverseMask(Identity));
778   EXPECT_TRUE(ShuffleVectorInst::isSingleSourceMask(Identity)); // identity is always single source
779   EXPECT_FALSE(ShuffleVectorInst::isZeroEltSplatMask(Identity));
780   EXPECT_FALSE(ShuffleVectorInst::isTransposeMask(Identity));
781 
782   Constant *Select = ConstantVector::get({CU, C1, C5});
783   EXPECT_FALSE(ShuffleVectorInst::isIdentityMask(Select));
784   EXPECT_TRUE(ShuffleVectorInst::isSelectMask(Select));
785   EXPECT_FALSE(ShuffleVectorInst::isReverseMask(Select));
786   EXPECT_FALSE(ShuffleVectorInst::isSingleSourceMask(Select));
787   EXPECT_FALSE(ShuffleVectorInst::isZeroEltSplatMask(Select));
788   EXPECT_FALSE(ShuffleVectorInst::isTransposeMask(Select));
789 
790   Constant *Reverse = ConstantVector::get({C3, C2, C1, CU});
791   EXPECT_FALSE(ShuffleVectorInst::isIdentityMask(Reverse));
792   EXPECT_FALSE(ShuffleVectorInst::isSelectMask(Reverse));
793   EXPECT_TRUE(ShuffleVectorInst::isReverseMask(Reverse));
794   EXPECT_TRUE(ShuffleVectorInst::isSingleSourceMask(Reverse)); // reverse is always single source
795   EXPECT_FALSE(ShuffleVectorInst::isZeroEltSplatMask(Reverse));
796   EXPECT_FALSE(ShuffleVectorInst::isTransposeMask(Reverse));
797 
798   Constant *SingleSource = ConstantVector::get({C2, C2, C0, CU});
799   EXPECT_FALSE(ShuffleVectorInst::isIdentityMask(SingleSource));
800   EXPECT_FALSE(ShuffleVectorInst::isSelectMask(SingleSource));
801   EXPECT_FALSE(ShuffleVectorInst::isReverseMask(SingleSource));
802   EXPECT_TRUE(ShuffleVectorInst::isSingleSourceMask(SingleSource));
803   EXPECT_FALSE(ShuffleVectorInst::isZeroEltSplatMask(SingleSource));
804   EXPECT_FALSE(ShuffleVectorInst::isTransposeMask(SingleSource));
805 
806   Constant *ZeroEltSplat = ConstantVector::get({C0, C0, CU, C0});
807   EXPECT_FALSE(ShuffleVectorInst::isIdentityMask(ZeroEltSplat));
808   EXPECT_FALSE(ShuffleVectorInst::isSelectMask(ZeroEltSplat));
809   EXPECT_FALSE(ShuffleVectorInst::isReverseMask(ZeroEltSplat));
810   EXPECT_TRUE(ShuffleVectorInst::isSingleSourceMask(ZeroEltSplat)); // 0-splat is always single source
811   EXPECT_TRUE(ShuffleVectorInst::isZeroEltSplatMask(ZeroEltSplat));
812   EXPECT_FALSE(ShuffleVectorInst::isTransposeMask(ZeroEltSplat));
813 
814   Constant *Transpose = ConstantVector::get({C0, C4, C2, C6});
815   EXPECT_FALSE(ShuffleVectorInst::isIdentityMask(Transpose));
816   EXPECT_FALSE(ShuffleVectorInst::isSelectMask(Transpose));
817   EXPECT_FALSE(ShuffleVectorInst::isReverseMask(Transpose));
818   EXPECT_FALSE(ShuffleVectorInst::isSingleSourceMask(Transpose));
819   EXPECT_FALSE(ShuffleVectorInst::isZeroEltSplatMask(Transpose));
820   EXPECT_TRUE(ShuffleVectorInst::isTransposeMask(Transpose));
821 
822   // More tests to make sure the logic is/stays correct...
823   EXPECT_TRUE(ShuffleVectorInst::isIdentityMask(ConstantVector::get({CU, C1, CU, C3})));
824   EXPECT_TRUE(ShuffleVectorInst::isIdentityMask(ConstantVector::get({C4, CU, C6, CU})));
825 
826   EXPECT_TRUE(ShuffleVectorInst::isSelectMask(ConstantVector::get({C4, C1, C6, CU})));
827   EXPECT_TRUE(ShuffleVectorInst::isSelectMask(ConstantVector::get({CU, C1, C6, C3})));
828 
829   EXPECT_TRUE(ShuffleVectorInst::isReverseMask(ConstantVector::get({C7, C6, CU, C4})));
830   EXPECT_TRUE(ShuffleVectorInst::isReverseMask(ConstantVector::get({C3, CU, C1, CU})));
831 
832   EXPECT_TRUE(ShuffleVectorInst::isSingleSourceMask(ConstantVector::get({C7, C5, CU, C7})));
833   EXPECT_TRUE(ShuffleVectorInst::isSingleSourceMask(ConstantVector::get({C3, C0, CU, C3})));
834 
835   EXPECT_TRUE(ShuffleVectorInst::isZeroEltSplatMask(ConstantVector::get({C4, CU, CU, C4})));
836   EXPECT_TRUE(ShuffleVectorInst::isZeroEltSplatMask(ConstantVector::get({CU, C0, CU, C0})));
837 
838   EXPECT_TRUE(ShuffleVectorInst::isTransposeMask(ConstantVector::get({C1, C5, C3, C7})));
839   EXPECT_TRUE(ShuffleVectorInst::isTransposeMask(ConstantVector::get({C1, C3})));
840 }
841 
TEST(InstructionsTest,SkipDebug)842 TEST(InstructionsTest, SkipDebug) {
843   LLVMContext C;
844   std::unique_ptr<Module> M = parseIR(C,
845                                       R"(
846       declare void @llvm.dbg.value(metadata, metadata, metadata)
847 
848       define void @f() {
849       entry:
850         call void @llvm.dbg.value(metadata i32 0, metadata !11, metadata !DIExpression()), !dbg !13
851         ret void
852       }
853 
854       !llvm.dbg.cu = !{!0}
855       !llvm.module.flags = !{!3, !4}
856       !0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 6.0.0", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !2)
857       !1 = !DIFile(filename: "t2.c", directory: "foo")
858       !2 = !{}
859       !3 = !{i32 2, !"Dwarf Version", i32 4}
860       !4 = !{i32 2, !"Debug Info Version", i32 3}
861       !8 = distinct !DISubprogram(name: "f", scope: !1, file: !1, line: 1, type: !9, isLocal: false, isDefinition: true, scopeLine: 1, isOptimized: false, unit: !0, retainedNodes: !2)
862       !9 = !DISubroutineType(types: !10)
863       !10 = !{null}
864       !11 = !DILocalVariable(name: "x", scope: !8, file: !1, line: 2, type: !12)
865       !12 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
866       !13 = !DILocation(line: 2, column: 7, scope: !8)
867   )");
868   ASSERT_TRUE(M);
869   Function *F = cast<Function>(M->getNamedValue("f"));
870   BasicBlock &BB = F->front();
871 
872   // The first non-debug instruction is the terminator.
873   auto *Term = BB.getTerminator();
874   EXPECT_EQ(Term, BB.begin()->getNextNonDebugInstruction());
875   EXPECT_EQ(Term->getIterator(), skipDebugIntrinsics(BB.begin()));
876 
877   // After the terminator, there are no non-debug instructions.
878   EXPECT_EQ(nullptr, Term->getNextNonDebugInstruction());
879 }
880 
881 } // end anonymous namespace
882 } // end namespace llvm
883