AArch64CallLowering.h revision 360784 
1//===- AArch64CallLowering.h - Call lowering --------------------*- 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/// \file
10/// This file describes how to lower LLVM calls to machine code calls.
11///
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_LIB_TARGET_AARCH64_AARCH64CALLLOWERING_H
15#define LLVM_LIB_TARGET_AARCH64_AARCH64CALLLOWERING_H
16
17#include "llvm/ADT/ArrayRef.h"
18#include "llvm/CodeGen/GlobalISel/CallLowering.h"
19#include "llvm/IR/CallingConv.h"
20#include <cstdint>
21#include <functional>
22
23namespace llvm {
24
25class AArch64TargetLowering;
26class CCValAssign;
27class DataLayout;
28class MachineIRBuilder;
29class MachineRegisterInfo;
30class Type;
31
32class AArch64CallLowering: public CallLowering {
33public:
34  AArch64CallLowering(const AArch64TargetLowering &TLI);
35
36  bool lowerReturn(MachineIRBuilder &MIRBuilder, const Value *Val,
37                   ArrayRef<Register> VRegs,
38                   Register SwiftErrorVReg) const override;
39
40  bool lowerFormalArguments(MachineIRBuilder &MIRBuilder, const Function &F,
41                            ArrayRef<ArrayRef<Register>> VRegs) const override;
42
43  bool lowerCall(MachineIRBuilder &MIRBuilder,
44                 CallLoweringInfo &Info) const override;
45
46  /// Returns true if the call can be lowered as a tail call.
47  bool
48  isEligibleForTailCallOptimization(MachineIRBuilder &MIRBuilder,
49                                    CallLoweringInfo &Info,
50                                    SmallVectorImpl<ArgInfo> &InArgs,
51                                    SmallVectorImpl<ArgInfo> &OutArgs) const;
52
53  bool supportSwiftError() const override { return true; }
54
55private:
56  using RegHandler = std::function<void(MachineIRBuilder &, Type *, unsigned,
57                                        CCValAssign &)>;
58
59  using MemHandler =
60      std::function<void(MachineIRBuilder &, int, CCValAssign &)>;
61
62  void splitToValueTypes(const ArgInfo &OrigArgInfo,
63                         SmallVectorImpl<ArgInfo> &SplitArgs,
64                         const DataLayout &DL, MachineRegisterInfo &MRI,
65                         CallingConv::ID CallConv) const;
66
67  bool lowerTailCall(MachineIRBuilder &MIRBuilder, CallLoweringInfo &Info,
68                     SmallVectorImpl<ArgInfo> &OutArgs) const;
69
70  bool
71  doCallerAndCalleePassArgsTheSameWay(CallLoweringInfo &Info,
72                                      MachineFunction &MF,
73                                      SmallVectorImpl<ArgInfo> &InArgs) const;
74
75  bool
76  areCalleeOutgoingArgsTailCallable(CallLoweringInfo &Info, MachineFunction &MF,
77                                    SmallVectorImpl<ArgInfo> &OutArgs) const;
78};
79
80} // end namespace llvm
81
82#endif // LLVM_LIB_TARGET_AARCH64_AARCH64CALLLOWERING_H
83