1 //===- llvm/CodeGen/GCMetadataPrinter.h - Prints asm GC tables --*- C++ -*-===// 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 // The abstract base class GCMetadataPrinter supports writing GC metadata tables 10 // as assembly code. This is a separate class from GCStrategy in order to allow 11 // users of the LLVM JIT to avoid linking with the AsmWriter. 12 // 13 // Subclasses of GCMetadataPrinter must be registered using the 14 // GCMetadataPrinterRegistry. This is separate from the GCStrategy itself 15 // because these subclasses are logically plugins for the AsmWriter. 16 // 17 //===----------------------------------------------------------------------===// 18 19 #ifndef LLVM_CODEGEN_GCMETADATAPRINTER_H 20 #define LLVM_CODEGEN_GCMETADATAPRINTER_H 21 22 #include "llvm/Support/Registry.h" 23 24 namespace llvm { 25 26 class AsmPrinter; 27 class GCMetadataPrinter; 28 class GCModuleInfo; 29 class GCStrategy; 30 class Module; 31 class StackMaps; 32 33 /// GCMetadataPrinterRegistry - The GC assembly printer registry uses all the 34 /// defaults from Registry. 35 using GCMetadataPrinterRegistry = Registry<GCMetadataPrinter>; 36 37 extern template class LLVM_TEMPLATE_ABI Registry<GCMetadataPrinter>; 38 39 /// GCMetadataPrinter - Emits GC metadata as assembly code. Instances are 40 /// created, managed, and owned by the AsmPrinter. 41 class GCMetadataPrinter { 42 private: 43 friend class AsmPrinter; 44 45 GCStrategy *S; 46 47 protected: 48 // May only be subclassed. 49 GCMetadataPrinter(); 50 51 public: 52 GCMetadataPrinter(const GCMetadataPrinter &) = delete; 53 GCMetadataPrinter &operator=(const GCMetadataPrinter &) = delete; 54 virtual ~GCMetadataPrinter(); 55 56 GCStrategy &getStrategy() { return *S; } 57 58 /// Called before the assembly for the module is generated by 59 /// the AsmPrinter (but after target specific hooks.) 60 virtual void beginAssembly(Module &M, GCModuleInfo &Info, AsmPrinter &AP) {} 61 62 /// Called after the assembly for the module is generated by 63 /// the AsmPrinter (but before target specific hooks) 64 virtual void finishAssembly(Module &M, GCModuleInfo &Info, AsmPrinter &AP) {} 65 66 /// Called when the stack maps are generated. Return true if 67 /// stack maps with a custom format are generated. Otherwise 68 /// returns false and the default format will be used. 69 virtual bool emitStackMaps(StackMaps &SM, AsmPrinter &AP) { return false; } 70 }; 71 72 } // end namespace llvm 73 74 #endif // LLVM_CODEGEN_GCMETADATAPRINTER_H 75