1 //===-- LLVMTargetMachine.cpp - Implement the LLVMTargetMachine class -----===//
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 // This file implements the LLVMTargetMachine class.
10 //
11 //===----------------------------------------------------------------------===//
12
13 #include "llvm/Analysis/Passes.h"
14 #include "llvm/CodeGen/AsmPrinter.h"
15 #include "llvm/CodeGen/BasicTTIImpl.h"
16 #include "llvm/CodeGen/MachineModuleInfo.h"
17 #include "llvm/CodeGen/Passes.h"
18 #include "llvm/CodeGen/TargetPassConfig.h"
19 #include "llvm/IR/LegacyPassManager.h"
20 #include "llvm/MC/MCAsmBackend.h"
21 #include "llvm/MC/MCAsmInfo.h"
22 #include "llvm/MC/MCCodeEmitter.h"
23 #include "llvm/MC/MCContext.h"
24 #include "llvm/MC/MCInstrInfo.h"
25 #include "llvm/MC/MCObjectWriter.h"
26 #include "llvm/MC/MCStreamer.h"
27 #include "llvm/MC/MCSubtargetInfo.h"
28 #include "llvm/Support/CommandLine.h"
29 #include "llvm/Support/ErrorHandling.h"
30 #include "llvm/Support/FormattedStream.h"
31 #include "llvm/Support/TargetRegistry.h"
32 #include "llvm/Target/TargetLoweringObjectFile.h"
33 #include "llvm/Target/TargetMachine.h"
34 #include "llvm/Target/TargetOptions.h"
35 #include "llvm/Transforms/Utils/CheriSetBounds.h"
36
37 using namespace llvm;
38
39 static cl::opt<bool> EnableTrapUnreachable("trap-unreachable",
40 cl::Hidden, cl::ZeroOrMore, cl::init(false),
41 cl::desc("Enable generating trap for unreachable"));
42
initAsmInfo()43 void LLVMTargetMachine::initAsmInfo() {
44 MRI.reset(TheTarget.createMCRegInfo(
45 getTargetTriple().str(), Options.MCOptions));
46 MII.reset(TheTarget.createMCInstrInfo());
47 // FIXME: Having an MCSubtargetInfo on the target machine is a hack due
48 // to some backends having subtarget feature dependent module level
49 // code generation. This is similar to the hack in the AsmPrinter for
50 // module level assembly etc.
51 STI.reset(TheTarget.createMCSubtargetInfo(
52 getTargetTriple().str(), getTargetCPU(), getTargetFeatureString()));
53
54 MCAsmInfo *TmpAsmInfo = TheTarget.createMCAsmInfo(
55 *MRI, getTargetTriple().str(), Options.MCOptions);
56 // TargetSelect.h moved to a different directory between LLVM 2.9 and 3.0,
57 // and if the old one gets included then MCAsmInfo will be NULL and
58 // we'll crash later.
59 // Provide the user with a useful error message about what's wrong.
60 assert(TmpAsmInfo && "MCAsmInfo not initialized. "
61 "Make sure you include the correct TargetSelect.h"
62 "and that InitializeAllTargetMCs() is being invoked!");
63
64 if (Options.DisableIntegratedAS)
65 TmpAsmInfo->setUseIntegratedAssembler(false);
66
67 TmpAsmInfo->setPreserveAsmComments(Options.MCOptions.PreserveAsmComments);
68
69 TmpAsmInfo->setCompressDebugSections(Options.CompressDebugSections);
70
71 TmpAsmInfo->setRelaxELFRelocations(Options.RelaxELFRelocations);
72
73 if (Options.ExceptionModel != ExceptionHandling::None)
74 TmpAsmInfo->setExceptionsType(Options.ExceptionModel);
75
76 AsmInfo.reset(TmpAsmInfo);
77 }
78
LLVMTargetMachine(const Target & T,StringRef DataLayoutString,const Triple & TT,StringRef CPU,StringRef FS,const TargetOptions & Options,Reloc::Model RM,CodeModel::Model CM,CodeGenOpt::Level OL)79 LLVMTargetMachine::LLVMTargetMachine(const Target &T,
80 StringRef DataLayoutString,
81 const Triple &TT, StringRef CPU,
82 StringRef FS, const TargetOptions &Options,
83 Reloc::Model RM, CodeModel::Model CM,
84 CodeGenOpt::Level OL)
85 : TargetMachine(T, DataLayoutString, TT, CPU, FS, Options) {
86 this->RM = RM;
87 this->CMModel = CM;
88 this->OptLevel = OL;
89
90 if (EnableTrapUnreachable)
91 this->Options.TrapUnreachable = true;
92 }
93
94 TargetTransformInfo
getTargetTransformInfo(const Function & F)95 LLVMTargetMachine::getTargetTransformInfo(const Function &F) {
96 return TargetTransformInfo(BasicTTIImpl(this, F));
97 }
98
99 /// addPassesToX helper drives creation and initialization of TargetPassConfig.
100 static TargetPassConfig *
addPassesToGenerateCode(LLVMTargetMachine & TM,PassManagerBase & PM,bool DisableVerify,MachineModuleInfoWrapperPass & MMIWP)101 addPassesToGenerateCode(LLVMTargetMachine &TM, PassManagerBase &PM,
102 bool DisableVerify,
103 MachineModuleInfoWrapperPass &MMIWP) {
104 // Targets may override createPassConfig to provide a target-specific
105 // subclass.
106 TargetPassConfig *PassConfig = TM.createPassConfig(PM);
107 // Set PassConfig options provided by TargetMachine.
108 PassConfig->setDisableVerify(DisableVerify);
109 PM.add(PassConfig);
110 PM.add(&MMIWP);
111
112 if (PassConfig->addISelPasses())
113 return nullptr;
114 PassConfig->addMachinePasses();
115 PassConfig->setInitialized();
116 return PassConfig;
117 }
118
addAsmPrinter(PassManagerBase & PM,raw_pwrite_stream & Out,raw_pwrite_stream * DwoOut,CodeGenFileType FileType,MCContext & Context)119 bool LLVMTargetMachine::addAsmPrinter(PassManagerBase &PM,
120 raw_pwrite_stream &Out,
121 raw_pwrite_stream *DwoOut,
122 CodeGenFileType FileType,
123 MCContext &Context) {
124 if (Options.MCOptions.MCSaveTempLabels)
125 Context.setAllowTemporaryLabels(false);
126
127 const MCSubtargetInfo &STI = *getMCSubtargetInfo();
128 const MCAsmInfo &MAI = *getMCAsmInfo();
129 const MCRegisterInfo &MRI = *getMCRegisterInfo();
130 const MCInstrInfo &MII = *getMCInstrInfo();
131
132 std::unique_ptr<MCStreamer> AsmStreamer;
133
134 switch (FileType) {
135 case CGFT_AssemblyFile: {
136 MCInstPrinter *InstPrinter = getTarget().createMCInstPrinter(
137 getTargetTriple(), MAI.getAssemblerDialect(), MAI, MII, MRI);
138
139 // Create a code emitter if asked to show the encoding.
140 std::unique_ptr<MCCodeEmitter> MCE;
141 if (Options.MCOptions.ShowMCEncoding)
142 MCE.reset(getTarget().createMCCodeEmitter(MII, MRI, Context));
143
144 std::unique_ptr<MCAsmBackend> MAB(
145 getTarget().createMCAsmBackend(STI, MRI, Options.MCOptions));
146 auto FOut = std::make_unique<formatted_raw_ostream>(Out);
147 MCStreamer *S = getTarget().createAsmStreamer(
148 Context, std::move(FOut), Options.MCOptions.AsmVerbose,
149 Options.MCOptions.MCUseDwarfDirectory, InstPrinter, std::move(MCE),
150 std::move(MAB), Options.MCOptions.ShowMCInst);
151 AsmStreamer.reset(S);
152 break;
153 }
154 case CGFT_ObjectFile: {
155 // Create the code emitter for the target if it exists. If not, .o file
156 // emission fails.
157 MCCodeEmitter *MCE = getTarget().createMCCodeEmitter(MII, MRI, Context);
158 MCAsmBackend *MAB =
159 getTarget().createMCAsmBackend(STI, MRI, Options.MCOptions);
160 if (!MCE || !MAB)
161 return true;
162
163 Triple T(getTargetTriple().str());
164 AsmStreamer.reset(getTarget().createMCObjectStreamer(
165 T, Context, std::unique_ptr<MCAsmBackend>(MAB),
166 DwoOut ? MAB->createDwoObjectWriter(Out, *DwoOut)
167 : MAB->createObjectWriter(Out),
168 std::unique_ptr<MCCodeEmitter>(MCE), STI, Options.MCOptions.MCRelaxAll,
169 Options.MCOptions.MCIncrementalLinkerCompatible,
170 /*DWARFMustBeAtTheEnd*/ true));
171 break;
172 }
173 case CGFT_Null:
174 // The Null output is intended for use for performance analysis and testing,
175 // not real users.
176 AsmStreamer.reset(getTarget().createNullStreamer(Context));
177 break;
178 }
179
180 // Create the AsmPrinter, which takes ownership of AsmStreamer if successful.
181 FunctionPass *Printer =
182 getTarget().createAsmPrinter(*this, std::move(AsmStreamer));
183 if (!Printer)
184 return true;
185
186 PM.add(Printer);
187 return false;
188 }
189
addPassesToEmitFile(PassManagerBase & PM,raw_pwrite_stream & Out,raw_pwrite_stream * DwoOut,CodeGenFileType FileType,bool DisableVerify,MachineModuleInfoWrapperPass * MMIWP)190 bool LLVMTargetMachine::addPassesToEmitFile(
191 PassManagerBase &PM, raw_pwrite_stream &Out, raw_pwrite_stream *DwoOut,
192 CodeGenFileType FileType, bool DisableVerify,
193 MachineModuleInfoWrapperPass *MMIWP) {
194 // Add common CodeGen passes.
195 if (!MMIWP)
196 MMIWP = new MachineModuleInfoWrapperPass(this);
197 TargetPassConfig *PassConfig =
198 addPassesToGenerateCode(*this, PM, DisableVerify, *MMIWP);
199 if (!PassConfig)
200 return true;
201
202 if (!TargetPassConfig::willCompleteCodeGenPipeline()) {
203 if (this->getTargetTriple().isOSAIX()) {
204 // On AIX, we might manifest MCSymbols during SDAG lowering. For MIR
205 // testing to be meaningful, we need to ensure that the symbols created
206 // are MCSymbolXCOFF variants, which requires that
207 // the TargetLoweringObjectFile instance has been initialized.
208 MCContext &Ctx = MMIWP->getMMI().getContext();
209 const_cast<TargetLoweringObjectFile &>(*this->getObjFileLowering())
210 .Initialize(Ctx, *this);
211 }
212 PM.add(createPrintMIRPass(Out));
213 } else if (addAsmPrinter(PM, Out, DwoOut, FileType,
214 MMIWP->getMMI().getContext()))
215 return true;
216
217 PM.add(createFreeMachineFunctionPass());
218 return false;
219 }
220
221 /// addPassesToEmitMC - Add passes to the specified pass manager to get
222 /// machine code emitted with the MCJIT. This method returns true if machine
223 /// code is not supported. It fills the MCContext Ctx pointer which can be
224 /// used to build custom MCStreamer.
225 ///
addPassesToEmitMC(PassManagerBase & PM,MCContext * & Ctx,raw_pwrite_stream & Out,bool DisableVerify)226 bool LLVMTargetMachine::addPassesToEmitMC(PassManagerBase &PM, MCContext *&Ctx,
227 raw_pwrite_stream &Out,
228 bool DisableVerify) {
229 // Add common CodeGen passes.
230 MachineModuleInfoWrapperPass *MMIWP = new MachineModuleInfoWrapperPass(this);
231 TargetPassConfig *PassConfig =
232 addPassesToGenerateCode(*this, PM, DisableVerify, *MMIWP);
233 if (!PassConfig)
234 return true;
235 assert(TargetPassConfig::willCompleteCodeGenPipeline() &&
236 "Cannot emit MC with limited codegen pipeline");
237
238 Ctx = &MMIWP->getMMI().getContext();
239 if (Options.MCOptions.MCSaveTempLabels)
240 Ctx->setAllowTemporaryLabels(false);
241
242 // Create the code emitter for the target if it exists. If not, .o file
243 // emission fails.
244 const MCSubtargetInfo &STI = *getMCSubtargetInfo();
245 const MCRegisterInfo &MRI = *getMCRegisterInfo();
246 MCCodeEmitter *MCE =
247 getTarget().createMCCodeEmitter(*getMCInstrInfo(), MRI, *Ctx);
248 MCAsmBackend *MAB =
249 getTarget().createMCAsmBackend(STI, MRI, Options.MCOptions);
250 if (!MCE || !MAB)
251 return true;
252
253 const Triple &T = getTargetTriple();
254 std::unique_ptr<MCStreamer> AsmStreamer(getTarget().createMCObjectStreamer(
255 T, *Ctx, std::unique_ptr<MCAsmBackend>(MAB), MAB->createObjectWriter(Out),
256 std::unique_ptr<MCCodeEmitter>(MCE), STI, Options.MCOptions.MCRelaxAll,
257 Options.MCOptions.MCIncrementalLinkerCompatible,
258 /*DWARFMustBeAtTheEnd*/ true));
259
260 // Create the AsmPrinter, which takes ownership of AsmStreamer if successful.
261 FunctionPass *Printer =
262 getTarget().createAsmPrinter(*this, std::move(AsmStreamer));
263 if (!Printer)
264 return true;
265
266 PM.add(Printer);
267 if (cheri::ShouldCollectCSetBoundsStats) {
268 PM.add(createLogCheriSetBoundsPass());
269 }
270 PM.add(createFreeMachineFunctionPass());
271
272 return false; // success!
273 }
274