xref: /llvm-project/llvm/unittests/CodeGen/MachineInstrTest.cpp (revision 1be62f0327cec94df3b60e3f2dc78384f48c6630)
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/Support/TargetRegistry.h"
14 #include "llvm/Support/TargetSelect.h"
15 #include "llvm/CodeGen/TargetFrameLowering.h"
16 #include "llvm/Target/TargetInstrInfo.h"
17 #include "llvm/Target/TargetLowering.h"
18 #include "llvm/Target/TargetMachine.h"
19 #include "llvm/Target/TargetOptions.h"
20 #include "llvm/Target/TargetSubtargetInfo.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 
95   return llvm::make_unique<MachineFunction>(F, *TM, FunctionNum, MMI);
96 }
97 
98 // This test makes sure that MachineInstr::isIdenticalTo handles Defs correctly
99 // for various combinations of IgnoreDefs, and also that it is symmetrical.
100 TEST(IsIdenticalToTest, DifferentDefs) {
101   auto MF = createMachineFunction();
102 
103   unsigned short NumOps = 2;
104   unsigned char NumDefs = 1;
105   MCOperandInfo OpInfo[] = {
106       {0, 0, MCOI::OPERAND_REGISTER, 0},
107       {0, 1 << MCOI::OptionalDef, MCOI::OPERAND_REGISTER, 0}};
108   MCInstrDesc MCID = {
109       0, NumOps,  NumDefs, 0,      0, 1ULL << MCID::HasOptionalDef,
110       0, nullptr, nullptr, OpInfo, 0, nullptr};
111 
112   // Create two MIs with different virtual reg defs and the same uses.
113   unsigned VirtualDef1 = -42; // The value doesn't matter, but the sign does.
114   unsigned VirtualDef2 = -43;
115   unsigned VirtualUse = -44;
116 
117   auto MI1 = MF->CreateMachineInstr(MCID, DebugLoc());
118   MI1->addOperand(*MF, MachineOperand::CreateReg(VirtualDef1, /*isDef*/ true));
119   MI1->addOperand(*MF, MachineOperand::CreateReg(VirtualUse, /*isDef*/ false));
120 
121   auto MI2 = MF->CreateMachineInstr(MCID, DebugLoc());
122   MI2->addOperand(*MF, MachineOperand::CreateReg(VirtualDef2, /*isDef*/ true));
123   MI2->addOperand(*MF, MachineOperand::CreateReg(VirtualUse, /*isDef*/ false));
124 
125   // Check that they are identical when we ignore virtual register defs, but not
126   // when we check defs.
127   ASSERT_FALSE(MI1->isIdenticalTo(*MI2, MachineInstr::CheckDefs));
128   ASSERT_FALSE(MI2->isIdenticalTo(*MI1, MachineInstr::CheckDefs));
129 
130   ASSERT_TRUE(MI1->isIdenticalTo(*MI2, MachineInstr::IgnoreVRegDefs));
131   ASSERT_TRUE(MI2->isIdenticalTo(*MI1, MachineInstr::IgnoreVRegDefs));
132 
133   // Create two MIs with different virtual reg defs, and a def or use of a
134   // sentinel register.
135   unsigned SentinelReg = 0;
136 
137   auto MI3 = MF->CreateMachineInstr(MCID, DebugLoc());
138   MI3->addOperand(*MF, MachineOperand::CreateReg(VirtualDef1, /*isDef*/ true));
139   MI3->addOperand(*MF, MachineOperand::CreateReg(SentinelReg, /*isDef*/ true));
140 
141   auto MI4 = MF->CreateMachineInstr(MCID, DebugLoc());
142   MI4->addOperand(*MF, MachineOperand::CreateReg(VirtualDef2, /*isDef*/ true));
143   MI4->addOperand(*MF, MachineOperand::CreateReg(SentinelReg, /*isDef*/ false));
144 
145   // Check that they are never identical.
146   ASSERT_FALSE(MI3->isIdenticalTo(*MI4, MachineInstr::CheckDefs));
147   ASSERT_FALSE(MI4->isIdenticalTo(*MI3, MachineInstr::CheckDefs));
148 
149   ASSERT_FALSE(MI3->isIdenticalTo(*MI4, MachineInstr::IgnoreVRegDefs));
150   ASSERT_FALSE(MI4->isIdenticalTo(*MI3, MachineInstr::IgnoreVRegDefs));
151 }
152 
153 // Check that MachineInstrExpressionTrait::isEqual is symmetric and in sync with
154 // MachineInstrExpressionTrait::getHashValue
155 void checkHashAndIsEqualMatch(MachineInstr *MI1, MachineInstr *MI2) {
156   bool IsEqual1 = MachineInstrExpressionTrait::isEqual(MI1, MI2);
157   bool IsEqual2 = MachineInstrExpressionTrait::isEqual(MI2, MI1);
158 
159   ASSERT_EQ(IsEqual1, IsEqual2);
160 
161   auto Hash1 = MachineInstrExpressionTrait::getHashValue(MI1);
162   auto Hash2 = MachineInstrExpressionTrait::getHashValue(MI2);
163 
164   ASSERT_EQ(IsEqual1, Hash1 == Hash2);
165 }
166 
167 // This test makes sure that MachineInstrExpressionTraits::isEqual is in sync
168 // with MachineInstrExpressionTraits::getHashValue.
169 TEST(MachineInstrExpressionTraitTest, IsEqualAgreesWithGetHashValue) {
170   auto MF = createMachineFunction();
171 
172   unsigned short NumOps = 2;
173   unsigned char NumDefs = 1;
174   MCOperandInfo OpInfo[] = {
175       {0, 0, MCOI::OPERAND_REGISTER, 0},
176       {0, 1 << MCOI::OptionalDef, MCOI::OPERAND_REGISTER, 0}};
177   MCInstrDesc MCID = {
178       0, NumOps,  NumDefs, 0,      0, 1ULL << MCID::HasOptionalDef,
179       0, nullptr, nullptr, OpInfo, 0, nullptr};
180 
181   // Define a series of instructions with different kinds of operands and make
182   // sure that the hash function is consistent with isEqual for various
183   // combinations of them.
184   unsigned VirtualDef1 = -42;
185   unsigned VirtualDef2 = -43;
186   unsigned VirtualReg = -44;
187   unsigned SentinelReg = 0;
188   unsigned PhysicalReg = 45;
189 
190   auto VD1VU = MF->CreateMachineInstr(MCID, DebugLoc());
191   VD1VU->addOperand(*MF,
192                     MachineOperand::CreateReg(VirtualDef1, /*isDef*/ true));
193   VD1VU->addOperand(*MF,
194                     MachineOperand::CreateReg(VirtualReg, /*isDef*/ false));
195 
196   auto VD2VU = MF->CreateMachineInstr(MCID, DebugLoc());
197   VD2VU->addOperand(*MF,
198                     MachineOperand::CreateReg(VirtualDef2, /*isDef*/ true));
199   VD2VU->addOperand(*MF,
200                     MachineOperand::CreateReg(VirtualReg, /*isDef*/ false));
201 
202   auto VD1SU = MF->CreateMachineInstr(MCID, DebugLoc());
203   VD1SU->addOperand(*MF,
204                     MachineOperand::CreateReg(VirtualDef1, /*isDef*/ true));
205   VD1SU->addOperand(*MF,
206                     MachineOperand::CreateReg(SentinelReg, /*isDef*/ false));
207 
208   auto VD1SD = MF->CreateMachineInstr(MCID, DebugLoc());
209   VD1SD->addOperand(*MF,
210                     MachineOperand::CreateReg(VirtualDef1, /*isDef*/ true));
211   VD1SD->addOperand(*MF,
212                     MachineOperand::CreateReg(SentinelReg, /*isDef*/ true));
213 
214   auto VD2PU = MF->CreateMachineInstr(MCID, DebugLoc());
215   VD2PU->addOperand(*MF,
216                     MachineOperand::CreateReg(VirtualDef2, /*isDef*/ true));
217   VD2PU->addOperand(*MF,
218                     MachineOperand::CreateReg(PhysicalReg, /*isDef*/ false));
219 
220   auto VD2PD = MF->CreateMachineInstr(MCID, DebugLoc());
221   VD2PD->addOperand(*MF,
222                     MachineOperand::CreateReg(VirtualDef2, /*isDef*/ true));
223   VD2PD->addOperand(*MF,
224                     MachineOperand::CreateReg(PhysicalReg, /*isDef*/ true));
225 
226   checkHashAndIsEqualMatch(VD1VU, VD2VU);
227   checkHashAndIsEqualMatch(VD1VU, VD1SU);
228   checkHashAndIsEqualMatch(VD1VU, VD1SD);
229   checkHashAndIsEqualMatch(VD1VU, VD2PU);
230   checkHashAndIsEqualMatch(VD1VU, VD2PD);
231 
232   checkHashAndIsEqualMatch(VD2VU, VD1SU);
233   checkHashAndIsEqualMatch(VD2VU, VD1SD);
234   checkHashAndIsEqualMatch(VD2VU, VD2PU);
235   checkHashAndIsEqualMatch(VD2VU, VD2PD);
236 
237   checkHashAndIsEqualMatch(VD1SU, VD1SD);
238   checkHashAndIsEqualMatch(VD1SU, VD2PU);
239   checkHashAndIsEqualMatch(VD1SU, VD2PD);
240 
241   checkHashAndIsEqualMatch(VD1SD, VD2PU);
242   checkHashAndIsEqualMatch(VD1SD, VD2PD);
243 
244   checkHashAndIsEqualMatch(VD2PU, VD2PD);
245 }
246 } // end namespace
247