xref: /freebsd/contrib/llvm-project/llvm/lib/CodeGen/CodeGenTargetMachineImpl.cpp (revision 770cf0a5f02dc8983a89c6568d741fbc25baa999)
1 //===-- CodeGenTargetMachineImpl.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 /// \file This file implements the CodeGenTargetMachineImpl class.
10 ///
11 //===----------------------------------------------------------------------===//
12 
13 #include "llvm/CodeGen/CodeGenTargetMachineImpl.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/MCInstPrinter.h"
25 #include "llvm/MC/MCInstrInfo.h"
26 #include "llvm/MC/MCObjectWriter.h"
27 #include "llvm/MC/MCRegisterInfo.h"
28 #include "llvm/MC/MCStreamer.h"
29 #include "llvm/MC/MCSubtargetInfo.h"
30 #include "llvm/MC/TargetRegistry.h"
31 #include "llvm/Support/CommandLine.h"
32 #include "llvm/Support/FormattedStream.h"
33 #include "llvm/Target/RegisterTargetPassConfigCallback.h"
34 #include "llvm/Target/TargetMachine.h"
35 #include "llvm/Target/TargetOptions.h"
36 using namespace llvm;
37 
38 static cl::opt<bool>
39     EnableTrapUnreachable("trap-unreachable", cl::Hidden,
40                           cl::desc("Enable generating trap for unreachable"));
41 
42 static cl::opt<bool> EnableNoTrapAfterNoreturn(
43     "no-trap-after-noreturn", cl::Hidden,
44     cl::desc("Do not emit a trap instruction for 'unreachable' IR instructions "
45              "after noreturn calls, even if --trap-unreachable is set."));
46 
47 void CodeGenTargetMachineImpl::initAsmInfo() {
48   MRI.reset(TheTarget.createMCRegInfo(getTargetTriple().str()));
49   assert(MRI && "Unable to create reg info");
50   MII.reset(TheTarget.createMCInstrInfo());
51   assert(MII && "Unable to create instruction info");
52   // FIXME: Having an MCSubtargetInfo on the target machine is a hack due
53   // to some backends having subtarget feature dependent module level
54   // code generation. This is similar to the hack in the AsmPrinter for
55   // module level assembly etc.
56   STI.reset(TheTarget.createMCSubtargetInfo(
57       getTargetTriple().str(), getTargetCPU(), getTargetFeatureString()));
58   assert(STI && "Unable to create subtarget info");
59 
60   MCAsmInfo *TmpAsmInfo = TheTarget.createMCAsmInfo(
61       *MRI, getTargetTriple().str(), Options.MCOptions);
62   // TargetSelect.h moved to a different directory between LLVM 2.9 and 3.0,
63   // and if the old one gets included then MCAsmInfo will be NULL and
64   // we'll crash later.
65   // Provide the user with a useful error message about what's wrong.
66   assert(TmpAsmInfo && "MCAsmInfo not initialized. "
67                        "Make sure you include the correct TargetSelect.h"
68                        "and that InitializeAllTargetMCs() is being invoked!");
69 
70   if (Options.BinutilsVersion.first > 0)
71     TmpAsmInfo->setBinutilsVersion(Options.BinutilsVersion);
72 
73   if (Options.DisableIntegratedAS) {
74     TmpAsmInfo->setUseIntegratedAssembler(false);
75     // If there is explict option disable integratedAS, we can't use it for
76     // inlineasm either.
77     TmpAsmInfo->setParseInlineAsmUsingAsmParser(false);
78   }
79 
80   TmpAsmInfo->setPreserveAsmComments(Options.MCOptions.PreserveAsmComments);
81 
82   TmpAsmInfo->setFullRegisterNames(Options.MCOptions.PPCUseFullRegisterNames);
83 
84   assert(TmpAsmInfo->getExceptionHandlingType() ==
85              getTargetTriple().getDefaultExceptionHandling() &&
86          "MCAsmInfo and Triple disagree on default exception handling type");
87 
88   if (Options.ExceptionModel != ExceptionHandling::None)
89     TmpAsmInfo->setExceptionsType(Options.ExceptionModel);
90 
91   AsmInfo.reset(TmpAsmInfo);
92 }
93 
94 CodeGenTargetMachineImpl::CodeGenTargetMachineImpl(
95     const Target &T, StringRef DataLayoutString, const Triple &TT,
96     StringRef CPU, StringRef FS, const TargetOptions &Options, Reloc::Model RM,
97     CodeModel::Model CM, CodeGenOptLevel OL)
98     : TargetMachine(T, DataLayoutString, TT, CPU, FS, Options) {
99   this->RM = RM;
100   this->CMModel = CM;
101   this->OptLevel = OL;
102 
103   if (EnableTrapUnreachable)
104     this->Options.TrapUnreachable = true;
105   if (EnableNoTrapAfterNoreturn)
106     this->Options.NoTrapAfterNoreturn = true;
107 }
108 
109 TargetTransformInfo
110 CodeGenTargetMachineImpl::getTargetTransformInfo(const Function &F) const {
111   return TargetTransformInfo(std::make_unique<BasicTTIImpl>(this, F));
112 }
113 
114 /// addPassesToX helper drives creation and initialization of TargetPassConfig.
115 static TargetPassConfig *
116 addPassesToGenerateCode(CodeGenTargetMachineImpl &TM, PassManagerBase &PM,
117                         bool DisableVerify,
118                         MachineModuleInfoWrapperPass &MMIWP) {
119   // Targets may override createPassConfig to provide a target-specific
120   // subclass.
121   TargetPassConfig *PassConfig = TM.createPassConfig(PM);
122   // Set PassConfig options provided by TargetMachine.
123   PassConfig->setDisableVerify(DisableVerify);
124   PM.add(PassConfig);
125   PM.add(&MMIWP);
126   invokeGlobalTargetPassConfigCallbacks(TM, PM, PassConfig);
127 
128   if (PassConfig->addISelPasses())
129     return nullptr;
130   PassConfig->addMachinePasses();
131   PassConfig->setInitialized();
132   return PassConfig;
133 }
134 
135 bool CodeGenTargetMachineImpl::addAsmPrinter(PassManagerBase &PM,
136                                              raw_pwrite_stream &Out,
137                                              raw_pwrite_stream *DwoOut,
138                                              CodeGenFileType FileType,
139                                              MCContext &Context) {
140   Expected<std::unique_ptr<MCStreamer>> MCStreamerOrErr =
141       createMCStreamer(Out, DwoOut, FileType, Context);
142   if (!MCStreamerOrErr) {
143     Context.reportError(SMLoc(), toString(MCStreamerOrErr.takeError()));
144     return true;
145   }
146 
147   // Create the AsmPrinter, which takes ownership of AsmStreamer if successful.
148   FunctionPass *Printer =
149       getTarget().createAsmPrinter(*this, std::move(*MCStreamerOrErr));
150   if (!Printer)
151     return true;
152 
153   PM.add(Printer);
154   return false;
155 }
156 
157 Expected<std::unique_ptr<MCStreamer>>
158 CodeGenTargetMachineImpl::createMCStreamer(raw_pwrite_stream &Out,
159                                            raw_pwrite_stream *DwoOut,
160                                            CodeGenFileType FileType,
161                                            MCContext &Context) {
162   const MCSubtargetInfo &STI = *getMCSubtargetInfo();
163   const MCAsmInfo &MAI = *getMCAsmInfo();
164   const MCRegisterInfo &MRI = *getMCRegisterInfo();
165   const MCInstrInfo &MII = *getMCInstrInfo();
166 
167   std::unique_ptr<MCStreamer> AsmStreamer;
168 
169   switch (FileType) {
170   case CodeGenFileType::AssemblyFile: {
171     std::unique_ptr<MCInstPrinter> InstPrinter(getTarget().createMCInstPrinter(
172         getTargetTriple(),
173         Options.MCOptions.OutputAsmVariant.value_or(MAI.getAssemblerDialect()),
174         MAI, MII, MRI));
175     for (StringRef Opt : Options.MCOptions.InstPrinterOptions)
176       if (!InstPrinter->applyTargetSpecificCLOption(Opt))
177         return createStringError("invalid InstPrinter option '" + Opt + "'");
178 
179     // Create a code emitter if asked to show the encoding.
180     std::unique_ptr<MCCodeEmitter> MCE;
181     if (Options.MCOptions.ShowMCEncoding)
182       MCE.reset(getTarget().createMCCodeEmitter(MII, Context));
183 
184     std::unique_ptr<MCAsmBackend> MAB(
185         getTarget().createMCAsmBackend(STI, MRI, Options.MCOptions));
186     auto FOut = std::make_unique<formatted_raw_ostream>(Out);
187     MCStreamer *S = getTarget().createAsmStreamer(
188         Context, std::move(FOut), std::move(InstPrinter), std::move(MCE),
189         std::move(MAB));
190     AsmStreamer.reset(S);
191     break;
192   }
193   case CodeGenFileType::ObjectFile: {
194     // Create the code emitter for the target if it exists.  If not, .o file
195     // emission fails.
196     MCCodeEmitter *MCE = getTarget().createMCCodeEmitter(MII, Context);
197     if (!MCE)
198       return make_error<StringError>("createMCCodeEmitter failed",
199                                      inconvertibleErrorCode());
200     MCAsmBackend *MAB =
201         getTarget().createMCAsmBackend(STI, MRI, Options.MCOptions);
202     if (!MAB)
203       return make_error<StringError>("createMCAsmBackend failed",
204                                      inconvertibleErrorCode());
205 
206     Triple T(getTargetTriple());
207     AsmStreamer.reset(getTarget().createMCObjectStreamer(
208         T, Context, std::unique_ptr<MCAsmBackend>(MAB),
209         DwoOut ? MAB->createDwoObjectWriter(Out, *DwoOut)
210                : MAB->createObjectWriter(Out),
211         std::unique_ptr<MCCodeEmitter>(MCE), STI));
212     break;
213   }
214   case CodeGenFileType::Null:
215     // The Null output is intended for use for performance analysis and testing,
216     // not real users.
217     AsmStreamer.reset(getTarget().createNullStreamer(Context));
218     break;
219   }
220 
221   return std::move(AsmStreamer);
222 }
223 
224 bool CodeGenTargetMachineImpl::addPassesToEmitFile(
225     PassManagerBase &PM, raw_pwrite_stream &Out, raw_pwrite_stream *DwoOut,
226     CodeGenFileType FileType, bool DisableVerify,
227     MachineModuleInfoWrapperPass *MMIWP) {
228   // Add common CodeGen passes.
229   if (!MMIWP)
230     MMIWP = new MachineModuleInfoWrapperPass(this);
231   TargetPassConfig *PassConfig =
232       addPassesToGenerateCode(*this, PM, DisableVerify, *MMIWP);
233   if (!PassConfig)
234     return true;
235 
236   if (TargetPassConfig::willCompleteCodeGenPipeline()) {
237     if (addAsmPrinter(PM, Out, DwoOut, FileType, MMIWP->getMMI().getContext()))
238       return true;
239   } else {
240     // MIR printing is redundant with -filetype=null.
241     if (FileType != CodeGenFileType::Null)
242       PM.add(createPrintMIRPass(Out));
243   }
244 
245   PM.add(createFreeMachineFunctionPass());
246   return false;
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 ///
254 bool CodeGenTargetMachineImpl::addPassesToEmitMC(PassManagerBase &PM,
255                                                  MCContext *&Ctx,
256                                                  raw_pwrite_stream &Out,
257                                                  bool DisableVerify) {
258   // Add common CodeGen passes.
259   MachineModuleInfoWrapperPass *MMIWP = new MachineModuleInfoWrapperPass(this);
260   TargetPassConfig *PassConfig =
261       addPassesToGenerateCode(*this, PM, DisableVerify, *MMIWP);
262   if (!PassConfig)
263     return true;
264   assert(TargetPassConfig::willCompleteCodeGenPipeline() &&
265          "Cannot emit MC with limited codegen pipeline");
266 
267   Ctx = &MMIWP->getMMI().getContext();
268   // libunwind is unable to load compact unwind dynamically, so we must generate
269   // DWARF unwind info for the JIT.
270   Options.MCOptions.EmitDwarfUnwind = EmitDwarfUnwindType::Always;
271 
272   // Create the code emitter for the target if it exists.  If not, .o file
273   // emission fails.
274   const MCSubtargetInfo &STI = *getMCSubtargetInfo();
275   const MCRegisterInfo &MRI = *getMCRegisterInfo();
276   std::unique_ptr<MCCodeEmitter> MCE(
277       getTarget().createMCCodeEmitter(*getMCInstrInfo(), *Ctx));
278   if (!MCE)
279     return true;
280   MCAsmBackend *MAB =
281       getTarget().createMCAsmBackend(STI, MRI, Options.MCOptions);
282   if (!MAB)
283     return true;
284 
285   const Triple &T = getTargetTriple();
286   std::unique_ptr<MCStreamer> AsmStreamer(getTarget().createMCObjectStreamer(
287       T, *Ctx, std::unique_ptr<MCAsmBackend>(MAB), MAB->createObjectWriter(Out),
288       std::move(MCE), STI));
289 
290   // Create the AsmPrinter, which takes ownership of AsmStreamer if successful.
291   FunctionPass *Printer =
292       getTarget().createAsmPrinter(*this, std::move(AsmStreamer));
293   if (!Printer)
294     return true;
295 
296   PM.add(Printer);
297   PM.add(createFreeMachineFunctionPass());
298 
299   return false; // success!
300 }
301