CallingConvLower.h revision 249423
1193323Sed//===-- llvm/CallingConvLower.h - Calling Conventions -----------*- C++ -*-===// 2193323Sed// 3193323Sed// The LLVM Compiler Infrastructure 4193323Sed// 5193323Sed// This file is distributed under the University of Illinois Open Source 6193323Sed// License. See LICENSE.TXT for details. 7193323Sed// 8193323Sed//===----------------------------------------------------------------------===// 9193323Sed// 10193323Sed// This file declares the CCState and CCValAssign classes, used for lowering 11193323Sed// and implementing calling conventions. 12193323Sed// 13193323Sed//===----------------------------------------------------------------------===// 14193323Sed 15193323Sed#ifndef LLVM_CODEGEN_CALLINGCONVLOWER_H 16193323Sed#define LLVM_CODEGEN_CALLINGCONVLOWER_H 17193323Sed 18193323Sed#include "llvm/ADT/SmallVector.h" 19249423Sdim#include "llvm/CodeGen/MachineFrameInfo.h" 20223017Sdim#include "llvm/CodeGen/MachineFunction.h" 21193323Sed#include "llvm/CodeGen/ValueTypes.h" 22249423Sdim#include "llvm/IR/CallingConv.h" 23210299Sed#include "llvm/Target/TargetCallingConv.h" 24193323Sed 25193323Sednamespace llvm { 26193323Sed class TargetRegisterInfo; 27193323Sed class TargetMachine; 28193323Sed class CCState; 29193323Sed 30193323Sed/// CCValAssign - Represent assignment of one arg/retval to a location. 31193323Sedclass CCValAssign { 32193323Sedpublic: 33193323Sed enum LocInfo { 34193323Sed Full, // The value fills the full location. 35193323Sed SExt, // The value is sign extended in the location. 36193323Sed ZExt, // The value is zero extended in the location. 37193323Sed AExt, // The value is extended with undefined upper bits. 38198090Srdivacky BCvt, // The value is bit-converted in the location. 39210299Sed VExt, // The value is vector-widened in the location. 40210299Sed // FIXME: Not implemented yet. Code that uses AExt to mean 41210299Sed // vector-widen should be fixed to use VExt instead. 42198090Srdivacky Indirect // The location contains pointer to the value. 43193323Sed // TODO: a subset of the value is in the location. 44193323Sed }; 45193323Sedprivate: 46193323Sed /// ValNo - This is the value number begin assigned (e.g. an argument number). 47193323Sed unsigned ValNo; 48198090Srdivacky 49193323Sed /// Loc is either a stack offset or a register number. 50193323Sed unsigned Loc; 51198090Srdivacky 52193323Sed /// isMem - True if this is a memory loc, false if it is a register loc. 53249423Sdim unsigned isMem : 1; 54198090Srdivacky 55193323Sed /// isCustom - True if this arg/retval requires special handling. 56249423Sdim unsigned isCustom : 1; 57193323Sed 58193323Sed /// Information about how the value is assigned. 59193323Sed LocInfo HTP : 6; 60198090Srdivacky 61193323Sed /// ValVT - The type of the value being assigned. 62218893Sdim MVT ValVT; 63193323Sed 64193323Sed /// LocVT - The type of the location being assigned to. 65218893Sdim MVT LocVT; 66193323Sedpublic: 67198090Srdivacky 68218893Sdim static CCValAssign getReg(unsigned ValNo, MVT ValVT, 69218893Sdim unsigned RegNo, MVT LocVT, 70193323Sed LocInfo HTP) { 71193323Sed CCValAssign Ret; 72193323Sed Ret.ValNo = ValNo; 73193323Sed Ret.Loc = RegNo; 74193323Sed Ret.isMem = false; 75193323Sed Ret.isCustom = false; 76193323Sed Ret.HTP = HTP; 77193323Sed Ret.ValVT = ValVT; 78193323Sed Ret.LocVT = LocVT; 79193323Sed return Ret; 80193323Sed } 81193323Sed 82218893Sdim static CCValAssign getCustomReg(unsigned ValNo, MVT ValVT, 83218893Sdim unsigned RegNo, MVT LocVT, 84193323Sed LocInfo HTP) { 85193323Sed CCValAssign Ret; 86193323Sed Ret = getReg(ValNo, ValVT, RegNo, LocVT, HTP); 87193323Sed Ret.isCustom = true; 88193323Sed return Ret; 89193323Sed } 90193323Sed 91218893Sdim static CCValAssign getMem(unsigned ValNo, MVT ValVT, 92218893Sdim unsigned Offset, MVT LocVT, 93193323Sed LocInfo HTP) { 94193323Sed CCValAssign Ret; 95193323Sed Ret.ValNo = ValNo; 96193323Sed Ret.Loc = Offset; 97193323Sed Ret.isMem = true; 98193323Sed Ret.isCustom = false; 99193323Sed Ret.HTP = HTP; 100193323Sed Ret.ValVT = ValVT; 101193323Sed Ret.LocVT = LocVT; 102193323Sed return Ret; 103193323Sed } 104198090Srdivacky 105218893Sdim static CCValAssign getCustomMem(unsigned ValNo, MVT ValVT, 106218893Sdim unsigned Offset, MVT LocVT, 107193323Sed LocInfo HTP) { 108193323Sed CCValAssign Ret; 109193323Sed Ret = getMem(ValNo, ValVT, Offset, LocVT, HTP); 110193323Sed Ret.isCustom = true; 111193323Sed return Ret; 112193323Sed } 113193323Sed 114193323Sed unsigned getValNo() const { return ValNo; } 115218893Sdim MVT getValVT() const { return ValVT; } 116193323Sed 117193323Sed bool isRegLoc() const { return !isMem; } 118193323Sed bool isMemLoc() const { return isMem; } 119198090Srdivacky 120193323Sed bool needsCustom() const { return isCustom; } 121193323Sed 122193323Sed unsigned getLocReg() const { assert(isRegLoc()); return Loc; } 123193323Sed unsigned getLocMemOffset() const { assert(isMemLoc()); return Loc; } 124218893Sdim MVT getLocVT() const { return LocVT; } 125198090Srdivacky 126193323Sed LocInfo getLocInfo() const { return HTP; } 127198090Srdivacky bool isExtInLoc() const { 128198090Srdivacky return (HTP == AExt || HTP == SExt || HTP == ZExt); 129198090Srdivacky } 130198090Srdivacky 131193323Sed}; 132193323Sed 133193323Sed/// CCAssignFn - This function assigns a location for Val, updating State to 134218893Sdim/// reflect the change. It returns 'true' if it failed to handle Val. 135218893Sdimtypedef bool CCAssignFn(unsigned ValNo, MVT ValVT, 136218893Sdim MVT LocVT, CCValAssign::LocInfo LocInfo, 137193323Sed ISD::ArgFlagsTy ArgFlags, CCState &State); 138193323Sed 139193323Sed/// CCCustomFn - This function assigns a location for Val, possibly updating 140193323Sed/// all args to reflect changes and indicates if it handled it. It must set 141193323Sed/// isCustom if it handles the arg and returns true. 142218893Sdimtypedef bool CCCustomFn(unsigned &ValNo, MVT &ValVT, 143218893Sdim MVT &LocVT, CCValAssign::LocInfo &LocInfo, 144193323Sed ISD::ArgFlagsTy &ArgFlags, CCState &State); 145193323Sed 146223017Sdim/// ParmContext - This enum tracks whether calling convention lowering is in 147223017Sdim/// the context of prologue or call generation. Not all backends make use of 148223017Sdim/// this information. 149223017Sdimtypedef enum { Unknown, Prologue, Call } ParmContext; 150221345Sdim 151193323Sed/// CCState - This class holds information needed while lowering arguments and 152193323Sed/// return values. It captures which registers are already assigned and which 153193323Sed/// stack slots are used. It provides accessors to allocate these values. 154193323Sedclass CCState { 155223017Sdimprivate: 156198090Srdivacky CallingConv::ID CallingConv; 157193323Sed bool IsVarArg; 158223017Sdim MachineFunction &MF; 159193323Sed const TargetMachine &TM; 160193323Sed const TargetRegisterInfo &TRI; 161193323Sed SmallVector<CCValAssign, 16> &Locs; 162198090Srdivacky LLVMContext &Context; 163198090Srdivacky 164193323Sed unsigned StackOffset; 165193323Sed SmallVector<uint32_t, 16> UsedRegs; 166221345Sdim unsigned FirstByValReg; 167221345Sdim bool FirstByValRegValid; 168223017Sdim 169223017Sdimprotected: 170221345Sdim ParmContext CallOrPrologue; 171223017Sdim 172193323Sedpublic: 173223017Sdim CCState(CallingConv::ID CC, bool isVarArg, MachineFunction &MF, 174223017Sdim const TargetMachine &TM, SmallVector<CCValAssign, 16> &locs, 175223017Sdim LLVMContext &C); 176198090Srdivacky 177193323Sed void addLoc(const CCValAssign &V) { 178193323Sed Locs.push_back(V); 179193323Sed } 180198090Srdivacky 181198090Srdivacky LLVMContext &getContext() const { return Context; } 182193323Sed const TargetMachine &getTarget() const { return TM; } 183223017Sdim MachineFunction &getMachineFunction() const { return MF; } 184198090Srdivacky CallingConv::ID getCallingConv() const { return CallingConv; } 185193323Sed bool isVarArg() const { return IsVarArg; } 186198090Srdivacky 187193323Sed unsigned getNextStackOffset() const { return StackOffset; } 188193323Sed 189193323Sed /// isAllocated - Return true if the specified register (or an alias) is 190193323Sed /// allocated. 191193323Sed bool isAllocated(unsigned Reg) const { 192193323Sed return UsedRegs[Reg/32] & (1 << (Reg&31)); 193193323Sed } 194198090Srdivacky 195198090Srdivacky /// AnalyzeFormalArguments - Analyze an array of argument values, 196193323Sed /// incorporating info about the formals into this state. 197198090Srdivacky void AnalyzeFormalArguments(const SmallVectorImpl<ISD::InputArg> &Ins, 198198090Srdivacky CCAssignFn Fn); 199198090Srdivacky 200198090Srdivacky /// AnalyzeReturn - Analyze the returned values of a return, 201193323Sed /// incorporating info about the result values into this state. 202198090Srdivacky void AnalyzeReturn(const SmallVectorImpl<ISD::OutputArg> &Outs, 203198090Srdivacky CCAssignFn Fn); 204193323Sed 205199481Srdivacky /// CheckReturn - Analyze the return values of a function, returning 206199481Srdivacky /// true if the return can be performed without sret-demotion, and 207199481Srdivacky /// false otherwise. 208210299Sed bool CheckReturn(const SmallVectorImpl<ISD::OutputArg> &ArgsFlags, 209199481Srdivacky CCAssignFn Fn); 210199481Srdivacky 211198090Srdivacky /// AnalyzeCallOperands - Analyze the outgoing arguments to a call, 212198090Srdivacky /// incorporating info about the passed values into this state. 213198090Srdivacky void AnalyzeCallOperands(const SmallVectorImpl<ISD::OutputArg> &Outs, 214198090Srdivacky CCAssignFn Fn); 215198090Srdivacky 216193323Sed /// AnalyzeCallOperands - Same as above except it takes vectors of types 217193323Sed /// and argument flags. 218218893Sdim void AnalyzeCallOperands(SmallVectorImpl<MVT> &ArgVTs, 219193323Sed SmallVectorImpl<ISD::ArgFlagsTy> &Flags, 220193323Sed CCAssignFn Fn); 221193323Sed 222198090Srdivacky /// AnalyzeCallResult - Analyze the return values of a call, 223193323Sed /// incorporating info about the passed values into this state. 224198090Srdivacky void AnalyzeCallResult(const SmallVectorImpl<ISD::InputArg> &Ins, 225198090Srdivacky CCAssignFn Fn); 226198090Srdivacky 227193323Sed /// AnalyzeCallResult - Same as above except it's specialized for calls which 228193323Sed /// produce a single value. 229218893Sdim void AnalyzeCallResult(MVT VT, CCAssignFn Fn); 230193323Sed 231193323Sed /// getFirstUnallocated - Return the first unallocated register in the set, or 232193323Sed /// NumRegs if they are all allocated. 233234353Sdim unsigned getFirstUnallocated(const uint16_t *Regs, unsigned NumRegs) const { 234193323Sed for (unsigned i = 0; i != NumRegs; ++i) 235193323Sed if (!isAllocated(Regs[i])) 236193323Sed return i; 237193323Sed return NumRegs; 238193323Sed } 239198090Srdivacky 240193323Sed /// AllocateReg - Attempt to allocate one register. If it is not available, 241193323Sed /// return zero. Otherwise, return the register, marking it and any aliases 242193323Sed /// as allocated. 243193323Sed unsigned AllocateReg(unsigned Reg) { 244193323Sed if (isAllocated(Reg)) return 0; 245193323Sed MarkAllocated(Reg); 246193323Sed return Reg; 247193323Sed } 248193323Sed 249193323Sed /// Version of AllocateReg with extra register to be shadowed. 250193323Sed unsigned AllocateReg(unsigned Reg, unsigned ShadowReg) { 251193323Sed if (isAllocated(Reg)) return 0; 252193323Sed MarkAllocated(Reg); 253193323Sed MarkAllocated(ShadowReg); 254193323Sed return Reg; 255193323Sed } 256193323Sed 257193323Sed /// AllocateReg - Attempt to allocate one of the specified registers. If none 258193323Sed /// are available, return zero. Otherwise, return the first one available, 259193323Sed /// marking it and any aliases as allocated. 260234353Sdim unsigned AllocateReg(const uint16_t *Regs, unsigned NumRegs) { 261193323Sed unsigned FirstUnalloc = getFirstUnallocated(Regs, NumRegs); 262193323Sed if (FirstUnalloc == NumRegs) 263193323Sed return 0; // Didn't find the reg. 264193323Sed 265193323Sed // Mark the register and any aliases as allocated. 266193323Sed unsigned Reg = Regs[FirstUnalloc]; 267193323Sed MarkAllocated(Reg); 268193323Sed return Reg; 269193323Sed } 270193323Sed 271193323Sed /// Version of AllocateReg with list of registers to be shadowed. 272234353Sdim unsigned AllocateReg(const uint16_t *Regs, const uint16_t *ShadowRegs, 273193323Sed unsigned NumRegs) { 274193323Sed unsigned FirstUnalloc = getFirstUnallocated(Regs, NumRegs); 275193323Sed if (FirstUnalloc == NumRegs) 276193323Sed return 0; // Didn't find the reg. 277193323Sed 278193323Sed // Mark the register and any aliases as allocated. 279193323Sed unsigned Reg = Regs[FirstUnalloc], ShadowReg = ShadowRegs[FirstUnalloc]; 280193323Sed MarkAllocated(Reg); 281193323Sed MarkAllocated(ShadowReg); 282193323Sed return Reg; 283193323Sed } 284193323Sed 285193323Sed /// AllocateStack - Allocate a chunk of stack space with the specified size 286193323Sed /// and alignment. 287193323Sed unsigned AllocateStack(unsigned Size, unsigned Align) { 288193323Sed assert(Align && ((Align-1) & Align) == 0); // Align is power of 2. 289193323Sed StackOffset = ((StackOffset + Align-1) & ~(Align-1)); 290193323Sed unsigned Result = StackOffset; 291193323Sed StackOffset += Size; 292243830Sdim MF.getFrameInfo()->ensureMaxAlignment(Align); 293193323Sed return Result; 294193323Sed } 295193323Sed 296212904Sdim /// Version of AllocateStack with extra register to be shadowed. 297212904Sdim unsigned AllocateStack(unsigned Size, unsigned Align, unsigned ShadowReg) { 298212904Sdim MarkAllocated(ShadowReg); 299212904Sdim return AllocateStack(Size, Align); 300212904Sdim } 301212904Sdim 302193323Sed // HandleByVal - Allocate a stack slot large enough to pass an argument by 303193323Sed // value. The size and alignment information of the argument is encoded in its 304193323Sed // parameter attribute. 305218893Sdim void HandleByVal(unsigned ValNo, MVT ValVT, 306218893Sdim MVT LocVT, CCValAssign::LocInfo LocInfo, 307193323Sed int MinSize, int MinAlign, ISD::ArgFlagsTy ArgFlags); 308193323Sed 309221345Sdim // First GPR that carries part of a byval aggregate that's split 310221345Sdim // between registers and memory. 311234353Sdim unsigned getFirstByValReg() const { return FirstByValRegValid ? FirstByValReg : 0; } 312221345Sdim void setFirstByValReg(unsigned r) { FirstByValReg = r; FirstByValRegValid = true; } 313221345Sdim void clearFirstByValReg() { FirstByValReg = 0; FirstByValRegValid = false; } 314234353Sdim bool isFirstByValRegValid() const { return FirstByValRegValid; } 315221345Sdim 316234353Sdim ParmContext getCallOrPrologue() const { return CallOrPrologue; } 317221345Sdim 318193323Sedprivate: 319193323Sed /// MarkAllocated - Mark a register and all of its aliases as allocated. 320193323Sed void MarkAllocated(unsigned Reg); 321193323Sed}; 322193323Sed 323193323Sed 324193323Sed 325193323Sed} // end namespace llvm 326193323Sed 327193323Sed#endif 328