1 //===-- llvm/CodeGen/GlobalISel/CallLowering.h - Call lowering --*- C++ -*-===// 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 /// \file 11 /// This file describes how to lower LLVM calls to machine code calls. 12 /// 13 //===----------------------------------------------------------------------===// 14 15 #ifndef LLVM_CODEGEN_GLOBALISEL_CALLLOWERING_H 16 #define LLVM_CODEGEN_GLOBALISEL_CALLLOWERING_H 17 18 #include "llvm/ADT/SmallVector.h" 19 #include "llvm/IR/Function.h" 20 21 namespace llvm { 22 // Forward declarations. 23 class MachineIRBuilder; 24 class TargetLowering; 25 class Value; 26 27 class CallLowering { 28 const TargetLowering *TLI; 29 protected: 30 /// Getter for generic TargetLowering class. 31 const TargetLowering *getTLI() const { 32 return TLI; 33 } 34 35 /// Getter for target specific TargetLowering class. 36 template <class XXXTargetLowering> 37 const XXXTargetLowering *getTLI() const { 38 return static_cast<const XXXTargetLowering *>(TLI); 39 } 40 public: 41 CallLowering(const TargetLowering *TLI) : TLI(TLI) {} 42 virtual ~CallLowering() {} 43 44 /// This hook must be implemented to lower outgoing return values, described 45 /// by \p Val, into the specified virtual register \p VReg. 46 /// This hook is used by GlobalISel. 47 /// 48 /// \return True if the lowering succeeds, false otherwise. 49 virtual bool lowerReturn(MachineIRBuilder &MIRBuilder, const Value *Val, 50 unsigned VReg) const { 51 return false; 52 } 53 54 /// This hook must be implemented to lower the incoming (formal) 55 /// arguments, described by \p Args, for GlobalISel. Each argument 56 /// must end up in the related virtual register described by VRegs. 57 /// In other words, the first argument should end up in VRegs[0], 58 /// the second in VRegs[1], and so on. 59 /// \p MIRBuilder is set to the proper insertion for the argument 60 /// lowering. 61 /// 62 /// \return True if the lowering succeeded, false otherwise. 63 virtual bool 64 lowerFormalArguments(MachineIRBuilder &MIRBuilder, 65 const Function::ArgumentListType &Args, 66 const SmallVectorImpl<unsigned> &VRegs) const { 67 return false; 68 } 69 }; 70 } // End namespace llvm. 71 72 #endif 73
