unittests/Linker/LinkModulesTest.cpp

   1 //===- llvm/unittest/Linker/LinkModulesTest.cpp - IRBuilder 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-c/Core.h"
  11 #include "llvm-c/Linker.h"
  12 #include "llvm/ADT/STLExtras.h"
  13 #include "llvm/AsmParser/Parser.h"
  14 #include "llvm/IR/BasicBlock.h"
  15 #include "llvm/IR/DataLayout.h"
  16 #include "llvm/IR/Function.h"
  17 #include "llvm/IR/IRBuilder.h"
  18 #include "llvm/IR/Module.h"
  19 #include "llvm/Linker/Linker.h"
  20 #include "llvm/Support/SourceMgr.h"
  21 #include "gtest/gtest.h"
  22
  23 using namespace llvm;
  24
  25 namespace {
  26
  27 class LinkModuleTest : public testing::Test {
  28 protected:
  29   void SetUp() override {
  30     M.reset(new Module("MyModule", Ctx));
  31     FunctionType *FTy = FunctionType::get(
  32         Type::getInt8PtrTy(Ctx), Type::getInt32Ty(Ctx), false /*=isVarArg*/);
  33     F = Function::Create(FTy, Function::ExternalLinkage, "ba_func", M.get());
  34     F->setCallingConv(CallingConv::C);
  35
  36     EntryBB = BasicBlock::Create(Ctx, "entry", F);
  37     SwitchCase1BB = BasicBlock::Create(Ctx, "switch.case.1", F);
  38     SwitchCase2BB = BasicBlock::Create(Ctx, "switch.case.2", F);
  39     ExitBB = BasicBlock::Create(Ctx, "exit", F);
  40
  41     AT = ArrayType::get(Type::getInt8PtrTy(Ctx), 3);
  42
  43     GV = new GlobalVariable(*M.get(), AT, false /*=isConstant*/,
  44                             GlobalValue::InternalLinkage, nullptr,"switch.bas");
  45
  46     // Global Initializer
  47     std::vector<Constant *> Init;
  48     Constant *SwitchCase1BA = BlockAddress::get(SwitchCase1BB);
  49     Init.push_back(SwitchCase1BA);
  50
  51     Constant *SwitchCase2BA = BlockAddress::get(SwitchCase2BB);
  52     Init.push_back(SwitchCase2BA);
  53
  54     ConstantInt *One = ConstantInt::get(Type::getInt32Ty(Ctx), 1);
  55     Constant *OnePtr = ConstantExpr::getCast(Instruction::IntToPtr, One,
  56                                              Type::getInt8PtrTy(Ctx));
  57     Init.push_back(OnePtr);
  58
  59     GV->setInitializer(ConstantArray::get(AT, Init));
  60   }
  61
  62   void TearDown() override { M.reset(); }
  63
  64   LLVMContext Ctx;
  65   std::unique_ptr<Module> M;
  66   Function *F;
  67   ArrayType *AT;
  68   GlobalVariable *GV;
  69   BasicBlock *EntryBB;
  70   BasicBlock *SwitchCase1BB;
  71   BasicBlock *SwitchCase2BB;
  72   BasicBlock *ExitBB;
  73 };
  74
  75 static void expectNoDiags(const DiagnosticInfo &DI, void *C) {
  76   EXPECT_TRUE(false);
  77 }
  78
  79 TEST_F(LinkModuleTest, BlockAddress) {
  80   IRBuilder<> Builder(EntryBB);
  81
  82   std::vector<Value *> GEPIndices;
  83   GEPIndices.push_back(ConstantInt::get(Type::getInt32Ty(Ctx), 0));
  84   GEPIndices.push_back(&*F->arg_begin());
  85
  86   Value *GEP = Builder.CreateGEP(AT, GV, GEPIndices, "switch.gep");
  87   Value *Load = Builder.CreateLoad(GEP, "switch.load");
  88
  89   Builder.CreateRet(Load);
  90
  91   Builder.SetInsertPoint(SwitchCase1BB);
  92   Builder.CreateBr(ExitBB);
  93
  94   Builder.SetInsertPoint(SwitchCase2BB);
  95   Builder.CreateBr(ExitBB);
  96
  97   Builder.SetInsertPoint(ExitBB);
  98   Builder.CreateRet(ConstantPointerNull::get(Type::getInt8PtrTy(Ctx)));
  99
 100   Module *LinkedModule = new Module("MyModuleLinked", Ctx);
 101   Ctx.setDiagnosticHandlerCallBack(expectNoDiags);
 102   Linker::linkModules(*LinkedModule, std::move(M));
 103
 104   // Check that the global "@switch.bas" is well-formed.
 105   const GlobalVariable *LinkedGV = LinkedModule->getNamedGlobal("switch.bas");
 106   const Constant *Init = LinkedGV->getInitializer();
 107
 108   // @switch.bas = internal global [3 x i8*]
 109   //   [i8* blockaddress(@ba_func, %switch.case.1),
 110   //    i8* blockaddress(@ba_func, %switch.case.2),
 111   //    i8* inttoptr (i32 1 to i8*)]
 112
 113   ArrayType *AT = ArrayType::get(Type::getInt8PtrTy(Ctx), 3);
 114   EXPECT_EQ(AT, Init->getType());
 115
 116   Value *Elem = Init->getOperand(0);
 117   ASSERT_TRUE(isa<BlockAddress>(Elem));
 118   EXPECT_EQ(cast<BlockAddress>(Elem)->getFunction(),
 119             LinkedModule->getFunction("ba_func"));
 120   EXPECT_EQ(cast<BlockAddress>(Elem)->getBasicBlock()->getParent(),
 121             LinkedModule->getFunction("ba_func"));
 122
 123   Elem = Init->getOperand(1);
 124   ASSERT_TRUE(isa<BlockAddress>(Elem));
 125   EXPECT_EQ(cast<BlockAddress>(Elem)->getFunction(),
 126             LinkedModule->getFunction("ba_func"));
 127   EXPECT_EQ(cast<BlockAddress>(Elem)->getBasicBlock()->getParent(),
 128             LinkedModule->getFunction("ba_func"));
 129
 130   delete LinkedModule;
 131 }
 132
 133 static Module *getExternal(LLVMContext &Ctx, StringRef FuncName) {
 134   // Create a module with an empty externally-linked function
 135   Module *M = new Module("ExternalModule", Ctx);
 136   FunctionType *FTy = FunctionType::get(
 137       Type::getVoidTy(Ctx), Type::getInt8PtrTy(Ctx), false /*=isVarArgs*/);
 138
 139   Function *F =
 140       Function::Create(FTy, Function::ExternalLinkage, FuncName, M);
 141   F->setCallingConv(CallingConv::C);
 142
 143   BasicBlock *BB = BasicBlock::Create(Ctx, "", F);
 144   IRBuilder<> Builder(BB);
 145   Builder.CreateRetVoid();
 146   return M;
 147 }
 148
 149 static Module *getInternal(LLVMContext &Ctx) {
 150   Module *InternalM = new Module("InternalModule", Ctx);
 151   FunctionType *FTy = FunctionType::get(
 152       Type::getVoidTy(Ctx), Type::getInt8PtrTy(Ctx), false /*=isVarArgs*/);
 153
 154   Function *F =
 155       Function::Create(FTy, Function::InternalLinkage, "bar", InternalM);
 156   F->setCallingConv(CallingConv::C);
 157
 158   BasicBlock *BB = BasicBlock::Create(Ctx, "", F);
 159   IRBuilder<> Builder(BB);
 160   Builder.CreateRetVoid();
 161
 162   StructType *STy = StructType::create(Ctx, PointerType::get(FTy, 0));
 163
 164   GlobalVariable *GV =
 165       new GlobalVariable(*InternalM, STy, false /*=isConstant*/,
 166                          GlobalValue::InternalLinkage, nullptr, "g");
 167
 168   GV->setInitializer(ConstantStruct::get(STy, F));
 169   return InternalM;
 170 }
 171
 172 TEST_F(LinkModuleTest, EmptyModule) {
 173   std::unique_ptr<Module> InternalM(getInternal(Ctx));
 174   std::unique_ptr<Module> EmptyM(new Module("EmptyModule1", Ctx));
 175   Ctx.setDiagnosticHandlerCallBack(expectNoDiags);
 176   Linker::linkModules(*EmptyM, std::move(InternalM));
 177 }
 178
 179 TEST_F(LinkModuleTest, EmptyModule2) {
 180   std::unique_ptr<Module> InternalM(getInternal(Ctx));
 181   std::unique_ptr<Module> EmptyM(new Module("EmptyModule1", Ctx));
 182   Ctx.setDiagnosticHandlerCallBack(expectNoDiags);
 183   Linker::linkModules(*InternalM, std::move(EmptyM));
 184 }
 185
 186 TEST_F(LinkModuleTest, TypeMerge) {
 187   LLVMContext C;
 188   SMDiagnostic Err;
 189
 190   const char *M1Str = "%t = type {i32}\n"
 191                       "@t1 = weak global %t zeroinitializer\n";
 192   std::unique_ptr<Module> M1 = parseAssemblyString(M1Str, Err, C);
 193
 194   const char *M2Str = "%t = type {i32}\n"
 195                       "@t2 = weak global %t zeroinitializer\n";
 196   std::unique_ptr<Module> M2 = parseAssemblyString(M2Str, Err, C);
 197
 198   Ctx.setDiagnosticHandlerCallBack(expectNoDiags);
 199   Linker::linkModules(*M1, std::move(M2));
 200
 201   EXPECT_EQ(M1->getNamedGlobal("t1")->getType(),
 202             M1->getNamedGlobal("t2")->getType());
 203 }
 204
 205 TEST_F(LinkModuleTest, NewCAPISuccess) {
 206   std::unique_ptr<Module> DestM(getExternal(Ctx, "foo"));
 207   std::unique_ptr<Module> SourceM(getExternal(Ctx, "bar"));
 208   LLVMBool Result =
 209       LLVMLinkModules2(wrap(DestM.get()), wrap(SourceM.release()));
 210   EXPECT_EQ(0, Result);
 211   // "bar" is present in destination module
 212   EXPECT_NE(nullptr, DestM->getFunction("bar"));
 213 }
 214
 215 static void diagnosticHandler(LLVMDiagnosticInfoRef DI, void *C) {
 216   auto *Err = reinterpret_cast<std::string *>(C);
 217   char *CErr = LLVMGetDiagInfoDescription(DI);
 218   *Err = CErr;
 219   LLVMDisposeMessage(CErr);
 220 }
 221
 222 TEST_F(LinkModuleTest, NewCAPIFailure) {
 223   // Symbol clash between two modules
 224   LLVMContext Ctx;
 225   std::string Err;
 226   LLVMContextSetDiagnosticHandler(wrap(&Ctx), diagnosticHandler, &Err);
 227
 228   std::unique_ptr<Module> DestM(getExternal(Ctx, "foo"));
 229   std::unique_ptr<Module> SourceM(getExternal(Ctx, "foo"));
 230   LLVMBool Result =
 231       LLVMLinkModules2(wrap(DestM.get()), wrap(SourceM.release()));
 232   EXPECT_EQ(1, Result);
 233   EXPECT_EQ("Linking globals named 'foo': symbol multiply defined!", Err);
 234 }
 235
 236 TEST_F(LinkModuleTest, MoveDistinctMDs) {
 237   LLVMContext C;
 238   SMDiagnostic Err;
 239
 240   const char *SrcStr = "define void @foo() !attach !0 {\n"
 241                        "entry:\n"
 242                        "  call void @llvm.md(metadata !1)\n"
 243                        "  ret void, !attach !2\n"
 244                        "}\n"
 245                        "declare void @llvm.md(metadata)\n"
 246                        "!named = !{!3, !4}\n"
 247                        "!0 = distinct !{}\n"
 248                        "!1 = distinct !{}\n"
 249                        "!2 = distinct !{}\n"
 250                        "!3 = distinct !{}\n"
 251                        "!4 = !{!3}\n";
 252
 253   std::unique_ptr<Module> Src = parseAssemblyString(SrcStr, Err, C);
 254   assert(Src);
 255   ASSERT_TRUE(Src.get());
 256
 257   // Get the addresses of the Metadata before merging.
 258   Function *F = &*Src->begin();
 259   ASSERT_EQ("foo", F->getName());
 260   BasicBlock *BB = &F->getEntryBlock();
 261   auto *CI = cast<CallInst>(&BB->front());
 262   auto *RI = cast<ReturnInst>(BB->getTerminator());
 263   NamedMDNode *NMD = &*Src->named_metadata_begin();
 264
 265   MDNode *M0 = F->getMetadata("attach");
 266   MDNode *M1 =
 267       cast<MDNode>(cast<MetadataAsValue>(CI->getArgOperand(0))->getMetadata());
 268   MDNode *M2 = RI->getMetadata("attach");
 269   MDNode *M3 = NMD->getOperand(0);
 270   MDNode *M4 = NMD->getOperand(1);
 271
 272   // Confirm a few things about the IR.
 273   EXPECT_TRUE(M0->isDistinct());
 274   EXPECT_TRUE(M1->isDistinct());
 275   EXPECT_TRUE(M2->isDistinct());
 276   EXPECT_TRUE(M3->isDistinct());
 277   EXPECT_TRUE(M4->isUniqued());
 278   EXPECT_EQ(M3, M4->getOperand(0));
 279
 280   // Link into destination module.
 281   auto Dst = llvm::make_unique<Module>("Linked", C);
 282   ASSERT_TRUE(Dst.get());
 283   Ctx.setDiagnosticHandlerCallBack(expectNoDiags);
 284   Linker::linkModules(*Dst, std::move(Src));
 285
 286   // Check that distinct metadata was moved, not cloned.  Even !4, the uniqued
 287   // node, should effectively be moved, since its only operand hasn't changed.
 288   F = &*Dst->begin();
 289   BB = &F->getEntryBlock();
 290   CI = cast<CallInst>(&BB->front());
 291   RI = cast<ReturnInst>(BB->getTerminator());
 292   NMD = &*Dst->named_metadata_begin();
 293
 294   EXPECT_EQ(M0, F->getMetadata("attach"));
 295   EXPECT_EQ(M1, cast<MetadataAsValue>(CI->getArgOperand(0))->getMetadata());
 296   EXPECT_EQ(M2, RI->getMetadata("attach"));
 297   EXPECT_EQ(M3, NMD->getOperand(0));
 298   EXPECT_EQ(M4, NMD->getOperand(1));
 299
 300   // Confirm a few things about the IR.  This shouldn't have changed.
 301   EXPECT_TRUE(M0->isDistinct());
 302   EXPECT_TRUE(M1->isDistinct());
 303   EXPECT_TRUE(M2->isDistinct());
 304   EXPECT_TRUE(M3->isDistinct());
 305   EXPECT_TRUE(M4->isUniqued());
 306   EXPECT_EQ(M3, M4->getOperand(0));
 307 }
 308
 309 TEST_F(LinkModuleTest, RemangleIntrinsics) {
 310   LLVMContext C;
 311   SMDiagnostic Err;
 312
 313   // We load two modules inside the same context C. In both modules there is a
 314   // "struct.rtx_def" type. In the module loaded the second (Bar) this type will
 315   // be renamed to "struct.rtx_def.0". Check that the intrinsics which have this
 316   // type in the signature are properly remangled.
 317   const char *FooStr =
 318     "%struct.rtx_def = type { i16 }\n"
 319     "define void @foo(%struct.rtx_def* %a, i8 %b, i32 %c) {\n"
 320     "  call void  @llvm.memset.p0s_struct.rtx_defs.i32(%struct.rtx_def* %a, i8 %b, i32 %c, i32 4, i1 true)\n"
 321     "  ret void\n"
 322     "}\n"
 323     "declare void @llvm.memset.p0s_struct.rtx_defs.i32(%struct.rtx_def*, i8, i32, i32, i1)\n";
 324
 325   const char *BarStr =
 326     "%struct.rtx_def = type { i16 }\n"
 327     "define void @bar(%struct.rtx_def* %a, i8 %b, i32 %c) {\n"
 328     "  call void  @llvm.memset.p0s_struct.rtx_defs.i32(%struct.rtx_def* %a, i8 %b, i32 %c, i32 4, i1 true)\n"
 329     "  ret void\n"
 330     "}\n"
 331     "declare void @llvm.memset.p0s_struct.rtx_defs.i32(%struct.rtx_def*, i8, i32, i32, i1)\n";
 332
 333   std::unique_ptr<Module> Foo = parseAssemblyString(FooStr, Err, C);
 334   assert(Foo);
 335   ASSERT_TRUE(Foo.get());
 336   // Foo is loaded first, so the type and the intrinsic have theis original
 337   // names.
 338   ASSERT_TRUE(Foo->getFunction("llvm.memset.p0s_struct.rtx_defs.i32"));
 339   ASSERT_FALSE(Foo->getFunction("llvm.memset.p0s_struct.rtx_defs.0.i32"));
 340
 341   std::unique_ptr<Module> Bar = parseAssemblyString(BarStr, Err, C);
 342   assert(Bar);
 343   ASSERT_TRUE(Bar.get());
 344   // Bar is loaded after Foo, so the type is renamed to struct.rtx_def.0. Check
 345   // that the intrinsic is also renamed.
 346   ASSERT_FALSE(Bar->getFunction("llvm.memset.p0s_struct.rtx_defs.i32"));
 347   ASSERT_TRUE(Bar->getFunction("llvm.memset.p0s_struct.rtx_def.0s.i32"));
 348
 349   // Link two modules together.
 350   auto Dst = llvm::make_unique<Module>("Linked", C);
 351   ASSERT_TRUE(Dst.get());
 352   Ctx.setDiagnosticHandlerCallBack(expectNoDiags);
 353   bool Failed = Linker::linkModules(*Foo, std::move(Bar));
 354   ASSERT_FALSE(Failed);
 355
 356   // "struct.rtx_def" from Foo and "struct.rtx_def.0" from Bar are isomorphic
 357   // types, so they must be uniquified by linker. Check that they use the same
 358   // intrinsic definition.
 359   Function *F = Foo->getFunction("llvm.memset.p0s_struct.rtx_defs.i32");
 360   ASSERT_EQ(F->getNumUses(), (unsigned)2);
 361 }
 362
 363 } // end anonymous namespace