xref: /llvm-project/llvm/unittests/CodeGen/MachineInstrTest.cpp (revision 238deafb92cf7ed83d646a25bfee3932146c73d5)
1 //===- MachineInstrTest.cpp -----------------------------------------------===//
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/CodeGen/MachineInstr.h"
11 #include "llvm/CodeGen/MachineFunction.h"
12 #include "llvm/CodeGen/MachineModuleInfo.h"
13 #include "llvm/CodeGen/TargetFrameLowering.h"
14 #include "llvm/CodeGen/TargetInstrInfo.h"
15 #include "llvm/CodeGen/TargetLowering.h"
16 #include "llvm/CodeGen/TargetSubtargetInfo.h"
17 #include "llvm/Support/TargetRegistry.h"
18 #include "llvm/Support/TargetSelect.h"
19 #include "llvm/Target/TargetMachine.h"
20 #include "llvm/Target/TargetOptions.h"
21 #include "gtest/gtest.h"
22 
23 using namespace llvm;
24 
25 namespace {
26 // Add a few Bogus backend classes so we can create MachineInstrs without
27 // depending on a real target.
28 class BogusTargetLowering : public TargetLowering {
29 public:
30   BogusTargetLowering(TargetMachine &TM) : TargetLowering(TM) {}
31 };
32 
33 class BogusFrameLowering : public TargetFrameLowering {
34 public:
35   BogusFrameLowering()
36       : TargetFrameLowering(TargetFrameLowering::StackGrowsDown, 4, 4) {}
37 
38   void emitPrologue(MachineFunction &MF,
39                     MachineBasicBlock &MBB) const override {}
40   void emitEpilogue(MachineFunction &MF,
41                     MachineBasicBlock &MBB) const override {}
42   bool hasFP(const MachineFunction &MF) const override { return false; }
43 };
44 
45 class BogusSubtarget : public TargetSubtargetInfo {
46 public:
47   BogusSubtarget(TargetMachine &TM)
48       : TargetSubtargetInfo(Triple(""), "", "", {}, {}, nullptr, nullptr,
49                             nullptr, nullptr, nullptr, nullptr, nullptr),
50         FL(), TL(TM) {}
51   ~BogusSubtarget() override {}
52 
53   const TargetFrameLowering *getFrameLowering() const override { return &FL; }
54 
55   const TargetLowering *getTargetLowering() const override { return &TL; }
56 
57   const TargetInstrInfo *getInstrInfo() const override { return &TII; }
58 
59 private:
60   BogusFrameLowering FL;
61   BogusTargetLowering TL;
62   TargetInstrInfo TII;
63 };
64 
65 class BogusTargetMachine : public LLVMTargetMachine {
66 public:
67   BogusTargetMachine()
68       : LLVMTargetMachine(Target(), "", Triple(""), "", "", TargetOptions(),
69                           Reloc::Static, CodeModel::Small, CodeGenOpt::Default),
70         ST(*this) {}
71   ~BogusTargetMachine() override {}
72 
73   const TargetSubtargetInfo *getSubtargetImpl(const Function &) const override {
74     return &ST;
75   }
76 
77 private:
78   BogusSubtarget ST;
79 };
80 
81 std::unique_ptr<BogusTargetMachine> createTargetMachine() {
82   return llvm::make_unique<BogusTargetMachine>();
83 }
84 
85 std::unique_ptr<MachineFunction> createMachineFunction() {
86   LLVMContext Ctx;
87   Module M("Module", Ctx);
88   auto Type = FunctionType::get(Type::getVoidTy(Ctx), false);
89   auto F = Function::Create(Type, GlobalValue::ExternalLinkage, "Test", &M);
90 
91   auto TM = createTargetMachine();
92   unsigned FunctionNum = 42;
93   MachineModuleInfo MMI(TM.get());
94   const TargetSubtargetInfo &STI = *TM->getSubtargetImpl(*F);
95 
96   return llvm::make_unique<MachineFunction>(*F, *TM, STI, FunctionNum, MMI);
97 }
98 
99 // This test makes sure that MachineInstr::isIdenticalTo handles Defs correctly
100 // for various combinations of IgnoreDefs, and also that it is symmetrical.
101 TEST(IsIdenticalToTest, DifferentDefs) {
102   auto MF = createMachineFunction();
103 
104   unsigned short NumOps = 2;
105   unsigned char NumDefs = 1;
106   MCOperandInfo OpInfo[] = {
107       {0, 0, MCOI::OPERAND_REGISTER, 0},
108       {0, 1 << MCOI::OptionalDef, MCOI::OPERAND_REGISTER, 0}};
109   MCInstrDesc MCID = {
110       0, NumOps,  NumDefs, 0,      0, 1ULL << MCID::HasOptionalDef,
111       0, nullptr, nullptr, OpInfo, 0, nullptr};
112 
113   // Create two MIs with different virtual reg defs and the same uses.
114   unsigned VirtualDef1 = -42; // The value doesn't matter, but the sign does.
115   unsigned VirtualDef2 = -43;
116   unsigned VirtualUse = -44;
117 
118   auto MI1 = MF->CreateMachineInstr(MCID, DebugLoc());
119   MI1->addOperand(*MF, MachineOperand::CreateReg(VirtualDef1, /*isDef*/ true));
120   MI1->addOperand(*MF, MachineOperand::CreateReg(VirtualUse, /*isDef*/ false));
121 
122   auto MI2 = MF->CreateMachineInstr(MCID, DebugLoc());
123   MI2->addOperand(*MF, MachineOperand::CreateReg(VirtualDef2, /*isDef*/ true));
124   MI2->addOperand(*MF, MachineOperand::CreateReg(VirtualUse, /*isDef*/ false));
125 
126   // Check that they are identical when we ignore virtual register defs, but not
127   // when we check defs.
128   ASSERT_FALSE(MI1->isIdenticalTo(*MI2, MachineInstr::CheckDefs));
129   ASSERT_FALSE(MI2->isIdenticalTo(*MI1, MachineInstr::CheckDefs));
130 
131   ASSERT_TRUE(MI1->isIdenticalTo(*MI2, MachineInstr::IgnoreVRegDefs));
132   ASSERT_TRUE(MI2->isIdenticalTo(*MI1, MachineInstr::IgnoreVRegDefs));
133 
134   // Create two MIs with different virtual reg defs, and a def or use of a
135   // sentinel register.
136   unsigned SentinelReg = 0;
137 
138   auto MI3 = MF->CreateMachineInstr(MCID, DebugLoc());
139   MI3->addOperand(*MF, MachineOperand::CreateReg(VirtualDef1, /*isDef*/ true));
140   MI3->addOperand(*MF, MachineOperand::CreateReg(SentinelReg, /*isDef*/ true));
141 
142   auto MI4 = MF->CreateMachineInstr(MCID, DebugLoc());
143   MI4->addOperand(*MF, MachineOperand::CreateReg(VirtualDef2, /*isDef*/ true));
144   MI4->addOperand(*MF, MachineOperand::CreateReg(SentinelReg, /*isDef*/ false));
145 
146   // Check that they are never identical.
147   ASSERT_FALSE(MI3->isIdenticalTo(*MI4, MachineInstr::CheckDefs));
148   ASSERT_FALSE(MI4->isIdenticalTo(*MI3, MachineInstr::CheckDefs));
149 
150   ASSERT_FALSE(MI3->isIdenticalTo(*MI4, MachineInstr::IgnoreVRegDefs));
151   ASSERT_FALSE(MI4->isIdenticalTo(*MI3, MachineInstr::IgnoreVRegDefs));
152 }
153 
154 // Check that MachineInstrExpressionTrait::isEqual is symmetric and in sync with
155 // MachineInstrExpressionTrait::getHashValue
156 void checkHashAndIsEqualMatch(MachineInstr *MI1, MachineInstr *MI2) {
157   bool IsEqual1 = MachineInstrExpressionTrait::isEqual(MI1, MI2);
158   bool IsEqual2 = MachineInstrExpressionTrait::isEqual(MI2, MI1);
159 
160   ASSERT_EQ(IsEqual1, IsEqual2);
161 
162   auto Hash1 = MachineInstrExpressionTrait::getHashValue(MI1);
163   auto Hash2 = MachineInstrExpressionTrait::getHashValue(MI2);
164 
165   ASSERT_EQ(IsEqual1, Hash1 == Hash2);
166 }
167 
168 // This test makes sure that MachineInstrExpressionTraits::isEqual is in sync
169 // with MachineInstrExpressionTraits::getHashValue.
170 TEST(MachineInstrExpressionTraitTest, IsEqualAgreesWithGetHashValue) {
171   auto MF = createMachineFunction();
172 
173   unsigned short NumOps = 2;
174   unsigned char NumDefs = 1;
175   MCOperandInfo OpInfo[] = {
176       {0, 0, MCOI::OPERAND_REGISTER, 0},
177       {0, 1 << MCOI::OptionalDef, MCOI::OPERAND_REGISTER, 0}};
178   MCInstrDesc MCID = {
179       0, NumOps,  NumDefs, 0,      0, 1ULL << MCID::HasOptionalDef,
180       0, nullptr, nullptr, OpInfo, 0, nullptr};
181 
182   // Define a series of instructions with different kinds of operands and make
183   // sure that the hash function is consistent with isEqual for various
184   // combinations of them.
185   unsigned VirtualDef1 = -42;
186   unsigned VirtualDef2 = -43;
187   unsigned VirtualReg = -44;
188   unsigned SentinelReg = 0;
189   unsigned PhysicalReg = 45;
190 
191   auto VD1VU = MF->CreateMachineInstr(MCID, DebugLoc());
192   VD1VU->addOperand(*MF,
193                     MachineOperand::CreateReg(VirtualDef1, /*isDef*/ true));
194   VD1VU->addOperand(*MF,
195                     MachineOperand::CreateReg(VirtualReg, /*isDef*/ false));
196 
197   auto VD2VU = MF->CreateMachineInstr(MCID, DebugLoc());
198   VD2VU->addOperand(*MF,
199                     MachineOperand::CreateReg(VirtualDef2, /*isDef*/ true));
200   VD2VU->addOperand(*MF,
201                     MachineOperand::CreateReg(VirtualReg, /*isDef*/ false));
202 
203   auto VD1SU = MF->CreateMachineInstr(MCID, DebugLoc());
204   VD1SU->addOperand(*MF,
205                     MachineOperand::CreateReg(VirtualDef1, /*isDef*/ true));
206   VD1SU->addOperand(*MF,
207                     MachineOperand::CreateReg(SentinelReg, /*isDef*/ false));
208 
209   auto VD1SD = MF->CreateMachineInstr(MCID, DebugLoc());
210   VD1SD->addOperand(*MF,
211                     MachineOperand::CreateReg(VirtualDef1, /*isDef*/ true));
212   VD1SD->addOperand(*MF,
213                     MachineOperand::CreateReg(SentinelReg, /*isDef*/ true));
214 
215   auto VD2PU = MF->CreateMachineInstr(MCID, DebugLoc());
216   VD2PU->addOperand(*MF,
217                     MachineOperand::CreateReg(VirtualDef2, /*isDef*/ true));
218   VD2PU->addOperand(*MF,
219                     MachineOperand::CreateReg(PhysicalReg, /*isDef*/ false));
220 
221   auto VD2PD = MF->CreateMachineInstr(MCID, DebugLoc());
222   VD2PD->addOperand(*MF,
223                     MachineOperand::CreateReg(VirtualDef2, /*isDef*/ true));
224   VD2PD->addOperand(*MF,
225                     MachineOperand::CreateReg(PhysicalReg, /*isDef*/ true));
226 
227   checkHashAndIsEqualMatch(VD1VU, VD2VU);
228   checkHashAndIsEqualMatch(VD1VU, VD1SU);
229   checkHashAndIsEqualMatch(VD1VU, VD1SD);
230   checkHashAndIsEqualMatch(VD1VU, VD2PU);
231   checkHashAndIsEqualMatch(VD1VU, VD2PD);
232 
233   checkHashAndIsEqualMatch(VD2VU, VD1SU);
234   checkHashAndIsEqualMatch(VD2VU, VD1SD);
235   checkHashAndIsEqualMatch(VD2VU, VD2PU);
236   checkHashAndIsEqualMatch(VD2VU, VD2PD);
237 
238   checkHashAndIsEqualMatch(VD1SU, VD1SD);
239   checkHashAndIsEqualMatch(VD1SU, VD2PU);
240   checkHashAndIsEqualMatch(VD1SU, VD2PD);
241 
242   checkHashAndIsEqualMatch(VD1SD, VD2PU);
243   checkHashAndIsEqualMatch(VD1SD, VD2PD);
244 
245   checkHashAndIsEqualMatch(VD2PU, VD2PD);
246 }
247 } // end namespace
248