1 //===-- llvm/Target/TargetMachine.h - Target Information --------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file defines the TargetMachine and LLVMTargetMachine classes.
12 //===----------------------------------------------------------------------===//
14 #ifndef LLVM_TARGET_TARGETMACHINE_H
15 #define LLVM_TARGET_TARGETMACHINE_H
17 #include "llvm/ADT/StringRef.h"
18 #include "llvm/ADT/Triple.h"
19 #include "llvm/IR/DataLayout.h"
20 #include "llvm/Pass.h"
21 #include "llvm/Support/CodeGen.h"
22 #include "llvm/Target/TargetOptions.h"
28 class InstrItineraryData;
31 class MachineFunctionInitializer;
37 class MCSubtargetInfo;
41 class TargetLibraryInfo;
42 class TargetFrameLowering;
43 class TargetIRAnalysis;
44 class TargetIntrinsicInfo;
46 class TargetPassConfig;
47 class TargetRegisterInfo;
48 class TargetSelectionDAGInfo;
49 class TargetSubtargetInfo;
50 class TargetTransformInfo;
51 class formatted_raw_ostream;
53 class raw_pwrite_stream;
54 class TargetLoweringObjectFile;
56 // The old pass manager infrastructure is hidden in a legacy namespace now.
58 class PassManagerBase;
60 using legacy::PassManagerBase;
62 //===----------------------------------------------------------------------===//
64 /// Primary interface to the complete machine description for the target
65 /// machine. All target-specific information should be accessible through this
69 TargetMachine(const TargetMachine &) = delete;
70 void operator=(const TargetMachine &) = delete;
71 protected: // Can only create subclasses.
72 TargetMachine(const Target &T, StringRef DataLayoutString,
73 const Triple &TargetTriple, StringRef CPU, StringRef FS,
74 const TargetOptions &Options);
76 /// The Target that this machine was created for.
77 const Target &TheTarget;
79 /// DataLayout for the target: keep ABI type size and alignment.
81 /// The DataLayout is created based on the string representation provided
82 /// during construction. It is kept here only to avoid reparsing the string
83 /// but should not really be used during compilation, because it has an
84 /// internal cache that is context specific.
87 /// Triple string, CPU name, and target feature strings the TargetMachine
88 /// instance is created with.
90 std::string TargetCPU;
93 /// Low level target information such as relocation model. Non-const to
94 /// allow resetting optimization level per-function.
95 MCCodeGenInfo *CodeGenInfo;
97 /// Contains target specific asm information.
98 const MCAsmInfo *AsmInfo;
100 const MCRegisterInfo *MRI;
101 const MCInstrInfo *MII;
102 const MCSubtargetInfo *STI;
104 unsigned RequireStructuredCFG : 1;
105 unsigned O0WantsFastISel : 1;
107 /// This API is here to support the C API, deprecated in 3.7 release.
108 /// This should never be used outside of legacy existing client.
109 const DataLayout &getDataLayout() const { return DL; }
110 friend struct C_API_PRIVATE_ACCESS;
113 mutable TargetOptions Options;
115 virtual ~TargetMachine();
117 const Target &getTarget() const { return TheTarget; }
119 const Triple &getTargetTriple() const { return TargetTriple; }
120 StringRef getTargetCPU() const { return TargetCPU; }
121 StringRef getTargetFeatureString() const { return TargetFS; }
123 /// Virtual method implemented by subclasses that returns a reference to that
124 /// target's TargetSubtargetInfo-derived member variable.
125 virtual const TargetSubtargetInfo *getSubtargetImpl(const Function &) const {
128 virtual TargetLoweringObjectFile *getObjFileLowering() const {
132 /// This method returns a pointer to the specified type of
133 /// TargetSubtargetInfo. In debug builds, it verifies that the object being
134 /// returned is of the correct type.
135 template <typename STC> const STC &getSubtarget(const Function &F) const {
136 return *static_cast<const STC*>(getSubtargetImpl(F));
139 /// Create a DataLayout.
140 const DataLayout createDataLayout() const { return DL; }
142 /// Test if a DataLayout if compatible with the CodeGen for this target.
144 /// The LLVM Module owns a DataLayout that is used for the target independent
145 /// optimizations and code generation. This hook provides a target specific
146 /// check on the validity of this DataLayout.
147 bool isCompatibleDataLayout(const DataLayout &Candidate) const {
148 return DL == Candidate;
151 /// Get the pointer size for this target.
153 /// This is the only time the DataLayout in the TargetMachine is used.
154 unsigned getPointerSize() const { return DL.getPointerSize(); }
156 /// \brief Reset the target options based on the function's attributes.
157 // FIXME: Remove TargetOptions that affect per-function code generation
158 // from TargetMachine.
159 void resetTargetOptions(const Function &F) const;
161 /// Return target specific asm information.
162 const MCAsmInfo *getMCAsmInfo() const { return AsmInfo; }
164 const MCRegisterInfo *getMCRegisterInfo() const { return MRI; }
165 const MCInstrInfo *getMCInstrInfo() const { return MII; }
166 const MCSubtargetInfo *getMCSubtargetInfo() const { return STI; }
168 /// If intrinsic information is available, return it. If not, return null.
169 virtual const TargetIntrinsicInfo *getIntrinsicInfo() const {
173 bool requiresStructuredCFG() const { return RequireStructuredCFG; }
174 void setRequiresStructuredCFG(bool Value) { RequireStructuredCFG = Value; }
176 /// Returns the code generation relocation model. The choices are static, PIC,
177 /// and dynamic-no-pic, and target default.
178 Reloc::Model getRelocationModel() const;
180 /// Returns the code model. The choices are small, kernel, medium, large, and
182 CodeModel::Model getCodeModel() const;
184 /// Returns the TLS model which should be used for the given global variable.
185 TLSModel::Model getTLSModel(const GlobalValue *GV) const;
187 /// Returns the optimization level: None, Less, Default, or Aggressive.
188 CodeGenOpt::Level getOptLevel() const;
190 /// \brief Overrides the optimization level.
191 void setOptLevel(CodeGenOpt::Level Level) const;
193 void setFastISel(bool Enable) { Options.EnableFastISel = Enable; }
194 bool getO0WantsFastISel() { return O0WantsFastISel; }
195 void setO0WantsFastISel(bool Enable) { O0WantsFastISel = Enable; }
197 bool shouldPrintMachineCode() const { return Options.PrintMachineCode; }
199 /// Returns the default value of asm verbosity.
201 bool getAsmVerbosityDefault() const {
202 return Options.MCOptions.AsmVerbose;
205 bool getUniqueSectionNames() const { return Options.UniqueSectionNames; }
207 /// Return true if data objects should be emitted into their own section,
208 /// corresponds to -fdata-sections.
209 bool getDataSections() const {
210 return Options.DataSections;
213 /// Return true if functions should be emitted into their own section,
214 /// corresponding to -ffunction-sections.
215 bool getFunctionSections() const {
216 return Options.FunctionSections;
219 /// \brief Get a \c TargetIRAnalysis appropriate for the target.
221 /// This is used to construct the new pass manager's target IR analysis pass,
222 /// set up appropriately for this target machine. Even the old pass manager
223 /// uses this to answer queries about the IR.
224 virtual TargetIRAnalysis getTargetIRAnalysis();
226 /// These enums are meant to be passed into addPassesToEmitFile to indicate
227 /// what type of file to emit, and returned by it to indicate what type of
228 /// file could actually be made.
229 enum CodeGenFileType {
232 CGFT_Null // Do not emit any output.
235 /// Add passes to the specified pass manager to get the specified file
236 /// emitted. Typically this will involve several steps of code generation.
237 /// This method should return true if emission of this file type is not
238 /// supported, or false on success.
239 virtual bool addPassesToEmitFile(
240 PassManagerBase &, raw_pwrite_stream &, CodeGenFileType,
241 bool /*DisableVerify*/ = true, AnalysisID /*StartBefore*/ = nullptr,
242 AnalysisID /*StartAfter*/ = nullptr, AnalysisID /*StopAfter*/ = nullptr,
243 MachineFunctionInitializer * /*MFInitializer*/ = nullptr) {
247 /// Add passes to the specified pass manager to get machine code emitted with
248 /// the MCJIT. This method returns true if machine code is not supported. It
249 /// fills the MCContext Ctx pointer which can be used to build custom
252 virtual bool addPassesToEmitMC(PassManagerBase &, MCContext *&,
254 bool /*DisableVerify*/ = true) {
258 void getNameWithPrefix(SmallVectorImpl<char> &Name, const GlobalValue *GV,
259 Mangler &Mang, bool MayAlwaysUsePrivate = false) const;
260 MCSymbol *getSymbol(const GlobalValue *GV, Mangler &Mang) const;
263 /// This class describes a target machine that is implemented with the LLVM
264 /// target-independent code generator.
266 class LLVMTargetMachine : public TargetMachine {
267 protected: // Can only create subclasses.
268 LLVMTargetMachine(const Target &T, StringRef DataLayoutString,
269 const Triple &TargetTriple, StringRef CPU, StringRef FS,
270 TargetOptions Options, Reloc::Model RM, CodeModel::Model CM,
271 CodeGenOpt::Level OL);
275 /// \brief Get a TargetIRAnalysis implementation for the target.
277 /// This analysis will produce a TTI result which uses the common code
278 /// generator to answer queries about the IR.
279 TargetIRAnalysis getTargetIRAnalysis() override;
281 /// Create a pass configuration object to be used by addPassToEmitX methods
282 /// for generating a pipeline of CodeGen passes.
283 virtual TargetPassConfig *createPassConfig(PassManagerBase &PM);
285 /// Add passes to the specified pass manager to get the specified file
286 /// emitted. Typically this will involve several steps of code generation.
287 bool addPassesToEmitFile(
288 PassManagerBase &PM, raw_pwrite_stream &Out, CodeGenFileType FileType,
289 bool DisableVerify = true, AnalysisID StartBefore = nullptr,
290 AnalysisID StartAfter = nullptr, AnalysisID StopAfter = nullptr,
291 MachineFunctionInitializer *MFInitializer = nullptr) override;
293 /// Add passes to the specified pass manager to get machine code emitted with
294 /// the MCJIT. This method returns true if machine code is not supported. It
295 /// fills the MCContext Ctx pointer which can be used to build custom
297 bool addPassesToEmitMC(PassManagerBase &PM, MCContext *&Ctx,
298 raw_pwrite_stream &OS,
299 bool DisableVerify = true) override;
302 } // End llvm namespace