1 //===-- LLVMTargetMachine.cpp - Implement the LLVMTargetMachine class -----===//
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 // This file implements the LLVMTargetMachine class.
11 //
12 //===----------------------------------------------------------------------===//
13
14 #include "llvm/Target/TargetMachine.h"
15
16 #include "llvm/Analysis/Passes.h"
17 #include "llvm/CodeGen/AsmPrinter.h"
18 #include "llvm/CodeGen/JumpInstrTables.h"
19 #include "llvm/CodeGen/MachineFunctionAnalysis.h"
20 #include "llvm/CodeGen/MachineModuleInfo.h"
21 #include "llvm/CodeGen/Passes.h"
22 #include "llvm/IR/IRPrintingPasses.h"
23 #include "llvm/IR/Verifier.h"
24 #include "llvm/MC/MCAsmInfo.h"
25 #include "llvm/MC/MCContext.h"
26 #include "llvm/MC/MCInstrInfo.h"
27 #include "llvm/MC/MCStreamer.h"
28 #include "llvm/MC/MCSubtargetInfo.h"
29 #include "llvm/PassManager.h"
30 #include "llvm/Support/CommandLine.h"
31 #include "llvm/Support/ErrorHandling.h"
32 #include "llvm/Support/FormattedStream.h"
33 #include "llvm/Support/TargetRegistry.h"
34 #include "llvm/Target/TargetInstrInfo.h"
35 #include "llvm/Target/TargetLowering.h"
36 #include "llvm/Target/TargetLoweringObjectFile.h"
37 #include "llvm/Target/TargetOptions.h"
38 #include "llvm/Target/TargetRegisterInfo.h"
39 #include "llvm/Target/TargetSubtargetInfo.h"
40 #include "llvm/Transforms/Scalar.h"
41 using namespace llvm;
42
43 // Enable or disable FastISel. Both options are needed, because
44 // FastISel is enabled by default with -fast, and we wish to be
45 // able to enable or disable fast-isel independently from -O0.
46 static cl::opt<cl::boolOrDefault>
47 EnableFastISelOption("fast-isel", cl::Hidden,
48 cl::desc("Enable the \"fast\" instruction selector"));
49
initAsmInfo()50 void LLVMTargetMachine::initAsmInfo() {
51 MCAsmInfo *TmpAsmInfo = TheTarget.createMCAsmInfo(*getRegisterInfo(),
52 TargetTriple);
53 // TargetSelect.h moved to a different directory between LLVM 2.9 and 3.0,
54 // and if the old one gets included then MCAsmInfo will be NULL and
55 // we'll crash later.
56 // Provide the user with a useful error message about what's wrong.
57 assert(TmpAsmInfo && "MCAsmInfo not initialized. "
58 "Make sure you include the correct TargetSelect.h"
59 "and that InitializeAllTargetMCs() is being invoked!");
60
61 if (Options.DisableIntegratedAS)
62 TmpAsmInfo->setUseIntegratedAssembler(false);
63
64 if (Options.CompressDebugSections)
65 TmpAsmInfo->setCompressDebugSections(true);
66
67 AsmInfo = TmpAsmInfo;
68 }
69
LLVMTargetMachine(const Target & T,StringRef Triple,StringRef CPU,StringRef FS,TargetOptions Options,Reloc::Model RM,CodeModel::Model CM,CodeGenOpt::Level OL)70 LLVMTargetMachine::LLVMTargetMachine(const Target &T, StringRef Triple,
71 StringRef CPU, StringRef FS,
72 TargetOptions Options,
73 Reloc::Model RM, CodeModel::Model CM,
74 CodeGenOpt::Level OL)
75 : TargetMachine(T, Triple, CPU, FS, Options) {
76 CodeGenInfo = T.createMCCodeGenInfo(Triple, RM, CM, OL);
77 }
78
addAnalysisPasses(PassManagerBase & PM)79 void LLVMTargetMachine::addAnalysisPasses(PassManagerBase &PM) {
80 PM.add(createBasicTargetTransformInfoPass(this));
81 }
82
83 /// addPassesToX helper drives creation and initialization of TargetPassConfig.
addPassesToGenerateCode(LLVMTargetMachine * TM,PassManagerBase & PM,bool DisableVerify,AnalysisID StartAfter,AnalysisID StopAfter)84 static MCContext *addPassesToGenerateCode(LLVMTargetMachine *TM,
85 PassManagerBase &PM,
86 bool DisableVerify,
87 AnalysisID StartAfter,
88 AnalysisID StopAfter) {
89
90 // Add internal analysis passes from the target machine.
91 TM->addAnalysisPasses(PM);
92
93 // Targets may override createPassConfig to provide a target-specific
94 // subclass.
95 TargetPassConfig *PassConfig = TM->createPassConfig(PM);
96 PassConfig->setStartStopPasses(StartAfter, StopAfter);
97
98 // Set PassConfig options provided by TargetMachine.
99 PassConfig->setDisableVerify(DisableVerify);
100
101 PM.add(PassConfig);
102
103 PassConfig->addIRPasses();
104
105 PassConfig->addCodeGenPrepare();
106
107 PassConfig->addPassesToHandleExceptions();
108
109 PassConfig->addISelPrepare();
110
111 // Install a MachineModuleInfo class, which is an immutable pass that holds
112 // all the per-module stuff we're generating, including MCContext.
113 MachineModuleInfo *MMI =
114 new MachineModuleInfo(*TM->getMCAsmInfo(), *TM->getRegisterInfo(),
115 &TM->getTargetLowering()->getObjFileLowering());
116 PM.add(MMI);
117
118 // Set up a MachineFunction for the rest of CodeGen to work on.
119 PM.add(new MachineFunctionAnalysis(*TM));
120
121 // Enable FastISel with -fast, but allow that to be overridden.
122 if (EnableFastISelOption == cl::BOU_TRUE ||
123 (TM->getOptLevel() == CodeGenOpt::None &&
124 EnableFastISelOption != cl::BOU_FALSE))
125 TM->setFastISel(true);
126
127 // Ask the target for an isel.
128 if (PassConfig->addInstSelector())
129 return nullptr;
130
131 PassConfig->addMachinePasses();
132
133 PassConfig->setInitialized();
134
135 return &MMI->getContext();
136 }
137
addPassesToEmitFile(PassManagerBase & PM,formatted_raw_ostream & Out,CodeGenFileType FileType,bool DisableVerify,AnalysisID StartAfter,AnalysisID StopAfter)138 bool LLVMTargetMachine::addPassesToEmitFile(PassManagerBase &PM,
139 formatted_raw_ostream &Out,
140 CodeGenFileType FileType,
141 bool DisableVerify,
142 AnalysisID StartAfter,
143 AnalysisID StopAfter) {
144 // Passes to handle jumptable function annotations. These can't be handled at
145 // JIT time, so we don't add them directly to addPassesToGenerateCode.
146 PM.add(createJumpInstrTableInfoPass());
147 PM.add(createJumpInstrTablesPass(Options.JTType));
148
149 // Add common CodeGen passes.
150 MCContext *Context = addPassesToGenerateCode(this, PM, DisableVerify,
151 StartAfter, StopAfter);
152 if (!Context)
153 return true;
154
155 if (StopAfter) {
156 // FIXME: The intent is that this should eventually write out a YAML file,
157 // containing the LLVM IR, the machine-level IR (when stopping after a
158 // machine-level pass), and whatever other information is needed to
159 // deserialize the code and resume compilation. For now, just write the
160 // LLVM IR.
161 PM.add(createPrintModulePass(Out));
162 return false;
163 }
164
165 if (Options.MCOptions.MCSaveTempLabels)
166 Context->setAllowTemporaryLabels(false);
167
168 const MCAsmInfo &MAI = *getMCAsmInfo();
169 const MCRegisterInfo &MRI = *getRegisterInfo();
170 const MCInstrInfo &MII = *getInstrInfo();
171 const MCSubtargetInfo &STI = getSubtarget<MCSubtargetInfo>();
172 std::unique_ptr<MCStreamer> AsmStreamer;
173
174 switch (FileType) {
175 case CGFT_AssemblyFile: {
176 MCInstPrinter *InstPrinter =
177 getTarget().createMCInstPrinter(MAI.getAssemblerDialect(), MAI,
178 MII, MRI, STI);
179
180 // Create a code emitter if asked to show the encoding.
181 MCCodeEmitter *MCE = nullptr;
182 if (Options.MCOptions.ShowMCEncoding)
183 MCE = getTarget().createMCCodeEmitter(MII, MRI, STI, *Context);
184
185 MCAsmBackend *MAB = getTarget().createMCAsmBackend(MRI, getTargetTriple(),
186 TargetCPU);
187 MCStreamer *S = getTarget().createAsmStreamer(
188 *Context, Out, Options.MCOptions.AsmVerbose,
189 Options.MCOptions.MCUseDwarfDirectory, InstPrinter, MCE, MAB,
190 Options.MCOptions.ShowMCInst);
191 AsmStreamer.reset(S);
192 break;
193 }
194 case CGFT_ObjectFile: {
195 // Create the code emitter for the target if it exists. If not, .o file
196 // emission fails.
197 MCCodeEmitter *MCE = getTarget().createMCCodeEmitter(MII, MRI, STI,
198 *Context);
199 MCAsmBackend *MAB = getTarget().createMCAsmBackend(MRI, getTargetTriple(),
200 TargetCPU);
201 if (!MCE || !MAB)
202 return true;
203
204 AsmStreamer.reset(getTarget().createMCObjectStreamer(
205 getTargetTriple(), *Context, *MAB, Out, MCE, STI,
206 Options.MCOptions.MCRelaxAll, Options.MCOptions.MCNoExecStack));
207 break;
208 }
209 case CGFT_Null:
210 // The Null output is intended for use for performance analysis and testing,
211 // not real users.
212 AsmStreamer.reset(getTarget().createNullStreamer(*Context));
213 break;
214 }
215
216 // Create the AsmPrinter, which takes ownership of AsmStreamer if successful.
217 FunctionPass *Printer = getTarget().createAsmPrinter(*this, *AsmStreamer);
218 if (!Printer)
219 return true;
220
221 // If successful, createAsmPrinter took ownership of AsmStreamer.
222 AsmStreamer.release();
223
224 PM.add(Printer);
225
226 return false;
227 }
228
229 /// addPassesToEmitMachineCode - Add passes to the specified pass manager to
230 /// get machine code emitted. This uses a JITCodeEmitter object to handle
231 /// actually outputting the machine code and resolving things like the address
232 /// of functions. This method should return true if machine code emission is
233 /// not supported.
234 ///
addPassesToEmitMachineCode(PassManagerBase & PM,JITCodeEmitter & JCE,bool DisableVerify)235 bool LLVMTargetMachine::addPassesToEmitMachineCode(PassManagerBase &PM,
236 JITCodeEmitter &JCE,
237 bool DisableVerify) {
238 // Add common CodeGen passes.
239 MCContext *Context = addPassesToGenerateCode(this, PM, DisableVerify, nullptr,
240 nullptr);
241 if (!Context)
242 return true;
243
244 addCodeEmitter(PM, JCE);
245
246 return false; // success!
247 }
248
249 /// addPassesToEmitMC - Add passes to the specified pass manager to get
250 /// machine code emitted with the MCJIT. This method returns true if machine
251 /// code is not supported. It fills the MCContext Ctx pointer which can be
252 /// used to build custom MCStreamer.
253 ///
addPassesToEmitMC(PassManagerBase & PM,MCContext * & Ctx,raw_ostream & Out,bool DisableVerify)254 bool LLVMTargetMachine::addPassesToEmitMC(PassManagerBase &PM,
255 MCContext *&Ctx,
256 raw_ostream &Out,
257 bool DisableVerify) {
258 // Add common CodeGen passes.
259 Ctx = addPassesToGenerateCode(this, PM, DisableVerify, nullptr, nullptr);
260 if (!Ctx)
261 return true;
262
263 if (Options.MCOptions.MCSaveTempLabels)
264 Ctx->setAllowTemporaryLabels(false);
265
266 // Create the code emitter for the target if it exists. If not, .o file
267 // emission fails.
268 const MCRegisterInfo &MRI = *getRegisterInfo();
269 const MCSubtargetInfo &STI = getSubtarget<MCSubtargetInfo>();
270 MCCodeEmitter *MCE = getTarget().createMCCodeEmitter(*getInstrInfo(), MRI,
271 STI, *Ctx);
272 MCAsmBackend *MAB = getTarget().createMCAsmBackend(MRI, getTargetTriple(),
273 TargetCPU);
274 if (!MCE || !MAB)
275 return true;
276
277 std::unique_ptr<MCStreamer> AsmStreamer;
278 AsmStreamer.reset(getTarget().createMCObjectStreamer(
279 getTargetTriple(), *Ctx, *MAB, Out, MCE, STI,
280 Options.MCOptions.MCRelaxAll, Options.MCOptions.MCNoExecStack));
281
282 // Create the AsmPrinter, which takes ownership of AsmStreamer if successful.
283 FunctionPass *Printer = getTarget().createAsmPrinter(*this, *AsmStreamer);
284 if (!Printer)
285 return true;
286
287 // If successful, createAsmPrinter took ownership of AsmStreamer.
288 AsmStreamer.release();
289
290 PM.add(Printer);
291
292 return false; // success!
293 }
294