1//===- ARMLegalizerInfo ------------------------------------------*- 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/// \file
9/// This file declares the targeting of the Machinelegalizer class for ARM.
10/// \todo This should be generated by TableGen.
11//===----------------------------------------------------------------------===//
12
13#ifndef LLVM_LIB_TARGET_ARM_ARMMACHINELEGALIZER_H
14#define LLVM_LIB_TARGET_ARM_ARMMACHINELEGALIZER_H
15
16#include "llvm/ADT/IndexedMap.h"
17#include "llvm/CodeGen/GlobalISel/GISelChangeObserver.h"
18#include "llvm/CodeGen/GlobalISel/LegalizerInfo.h"
19#include "llvm/CodeGen/RuntimeLibcalls.h"
20#include "llvm/IR/Instructions.h"
21
22namespace llvm {
23
24class ARMSubtarget;
25
26/// This class provides the information for the target register banks.
27class ARMLegalizerInfo : public LegalizerInfo {
28public:
29  ARMLegalizerInfo(const ARMSubtarget &ST);
30
31  bool legalizeCustom(MachineInstr &MI, MachineRegisterInfo &MRI,
32                      MachineIRBuilder &MIRBuilder,
33                      GISelChangeObserver &Observer) const override;
34
35private:
36  void setFCmpLibcallsGNU();
37  void setFCmpLibcallsAEABI();
38
39  struct FCmpLibcallInfo {
40    // Which libcall this is.
41    RTLIB::Libcall LibcallID;
42
43    // The predicate to be used when comparing the value returned by the
44    // function with a relevant constant (currently hard-coded to zero). This is
45    // necessary because often the libcall will return e.g. a value greater than
46    // 0 to represent 'true' and anything negative to represent 'false', or
47    // maybe 0 to represent 'true' and non-zero for 'false'. If no comparison is
48    // needed, this should be CmpInst::BAD_ICMP_PREDICATE.
49    CmpInst::Predicate Predicate;
50  };
51  using FCmpLibcallsList = SmallVector<FCmpLibcallInfo, 2>;
52
53  // Map from each FCmp predicate to the corresponding libcall infos. A FCmp
54  // instruction may be lowered to one or two libcalls, which is why we need a
55  // list. If two libcalls are needed, their results will be OR'ed.
56  using FCmpLibcallsMapTy = IndexedMap<FCmpLibcallsList>;
57
58  FCmpLibcallsMapTy FCmp32Libcalls;
59  FCmpLibcallsMapTy FCmp64Libcalls;
60
61  // Get the libcall(s) corresponding to \p Predicate for operands of \p Size
62  // bits.
63  FCmpLibcallsList getFCmpLibcalls(CmpInst::Predicate, unsigned Size) const;
64};
65} // End llvm namespace.
66#endif
67