llvm/unittests/Target/AMDGPU/ExecMayBeModifiedBeforeAnyUse.cpp

   1 //===- llvm/unittests/Target/AMDGPU/ExecMayBeModifiedBeforeAnyUse.cpp -----===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8
   9 #include "AMDGPUTargetMachine.h"
  10 #include "AMDGPUUnitTests.h"
  11 #include "llvm/CodeGen/MachineModuleInfo.h"
  12 #include "gtest/gtest.h"
  13
  14 using namespace llvm;
  15
  16 TEST(AMDGPU, ExecMayBeModifiedBeforeAnyUse) {
  17   auto TM = createAMDGPUTargetMachine("amdgcn-amd-", "gfx906", "");
  18   if (!TM)
  19     GTEST_SKIP();
  20
  21   GCNSubtarget ST(TM->getTargetTriple(), std::string(TM->getTargetCPU()),
  22                   std::string(TM->getTargetFeatureString()), *TM);
  23
  24   LLVMContext Ctx;
  25   Module Mod("Module", Ctx);
  26   Mod.setDataLayout(TM->createDataLayout());
  27
  28   auto *Type = FunctionType::get(Type::getVoidTy(Ctx), false);
  29   auto *F = Function::Create(Type, GlobalValue::ExternalLinkage, "Test", &Mod);
  30
  31   MachineModuleInfo MMI(TM.get());
  32   auto MF =
  33       std::make_unique<MachineFunction>(*F, *TM, ST, MMI.getContext(), 42);
  34   auto *BB = MF->CreateMachineBasicBlock();
  35   MF->push_back(BB);
  36
  37   auto E = BB->end();
  38   DebugLoc DL;
  39   const auto &TII = *ST.getInstrInfo();
  40   auto &MRI = MF->getRegInfo();
  41
  42   // create machine IR
  43   Register R = MRI.createVirtualRegister(&AMDGPU::SReg_32RegClass);
  44
  45   MachineInstr *DefMI =
  46       BuildMI(*BB, E, DL, TII.get(AMDGPU::S_MOV_B32), R).addImm(42).getInstr();
  47
  48   auto First =
  49       BuildMI(*BB, E, DL, TII.get(AMDGPU::S_NOP)).addReg(R, RegState::Implicit);
  50
  51   BuildMI(*BB, E, DL, TII.get(AMDGPU::S_NOP)).addReg(R, RegState::Implicit);
  52
  53   // this violates the continuous sequence of R's uses for the first S_NOP
  54   First.addReg(R, RegState::Implicit);
  55
  56 #ifdef DEBUG_THIS_TEST
  57   MF->dump();
  58   MRI.dumpUses(R);
  59 #endif
  60
  61   // make sure execMayBeModifiedBeforeAnyUse doesn't crash
  62   ASSERT_FALSE(execMayBeModifiedBeforeAnyUse(MRI, R, *DefMI));
  63 }