xref: /freebsd/contrib/llvm-project/llvm/lib/Target/RISCV/RISCVSubtarget.h (revision ba3c1f5972d7b90feb6e6da47905ff2757e0fe57)
1 //===-- RISCVSubtarget.h - Define Subtarget for the RISCV -------*- 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 // This file declares the RISCV specific subclass of TargetSubtargetInfo.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #ifndef LLVM_LIB_TARGET_RISCV_RISCVSUBTARGET_H
14 #define LLVM_LIB_TARGET_RISCV_RISCVSUBTARGET_H
15 
16 #include "MCTargetDesc/RISCVBaseInfo.h"
17 #include "RISCVFrameLowering.h"
18 #include "RISCVISelLowering.h"
19 #include "RISCVInstrInfo.h"
20 #include "llvm/CodeGen/GlobalISel/CallLowering.h"
21 #include "llvm/CodeGen/GlobalISel/InstructionSelector.h"
22 #include "llvm/CodeGen/GlobalISel/LegalizerInfo.h"
23 #include "llvm/CodeGen/RegisterBankInfo.h"
24 #include "llvm/CodeGen/SelectionDAGTargetInfo.h"
25 #include "llvm/CodeGen/TargetSubtargetInfo.h"
26 #include "llvm/IR/DataLayout.h"
27 #include "llvm/Target/TargetMachine.h"
28 
29 #define GET_SUBTARGETINFO_HEADER
30 #include "RISCVGenSubtargetInfo.inc"
31 
32 namespace llvm {
33 class StringRef;
34 
35 class RISCVSubtarget : public RISCVGenSubtargetInfo {
36 public:
37   enum RISCVProcFamilyEnum : uint8_t {
38     Others,
39     SiFive7,
40   };
41 
42 private:
43   virtual void anchor();
44 
45   RISCVProcFamilyEnum RISCVProcFamily = Others;
46 
47 #define GET_SUBTARGETINFO_MACRO(ATTRIBUTE, DEFAULT, GETTER) \
48   bool ATTRIBUTE = DEFAULT;
49 #include "RISCVGenSubtargetInfo.inc"
50 
51   unsigned XLen = 32;
52   unsigned ZvlLen = 0;
53   MVT XLenVT = MVT::i32;
54   unsigned RVVVectorBitsMin;
55   unsigned RVVVectorBitsMax;
56   uint8_t MaxInterleaveFactor = 2;
57   RISCVABI::ABI TargetABI = RISCVABI::ABI_Unknown;
58   std::bitset<RISCV::NUM_TARGET_REGS> UserReservedRegister;
59   RISCVFrameLowering FrameLowering;
60   RISCVInstrInfo InstrInfo;
61   RISCVRegisterInfo RegInfo;
62   RISCVTargetLowering TLInfo;
63   SelectionDAGTargetInfo TSInfo;
64 
65   /// Initializes using the passed in CPU and feature strings so that we can
66   /// use initializer lists for subtarget initialization.
67   RISCVSubtarget &initializeSubtargetDependencies(const Triple &TT,
68                                                   StringRef CPU,
69                                                   StringRef TuneCPU,
70                                                   StringRef FS,
71                                                   StringRef ABIName);
72 
73 public:
74   // Initializes the data members to match that of the specified triple.
75   RISCVSubtarget(const Triple &TT, StringRef CPU, StringRef TuneCPU,
76                  StringRef FS, StringRef ABIName, unsigned RVVVectorBitsMin,
77                  unsigned RVVVectorLMULMax, const TargetMachine &TM);
78 
79   // Parses features string setting specified subtarget options. The
80   // definition of this function is auto-generated by tblgen.
81   void ParseSubtargetFeatures(StringRef CPU, StringRef TuneCPU, StringRef FS);
82 
83   const RISCVFrameLowering *getFrameLowering() const override {
84     return &FrameLowering;
85   }
86   const RISCVInstrInfo *getInstrInfo() const override { return &InstrInfo; }
87   const RISCVRegisterInfo *getRegisterInfo() const override {
88     return &RegInfo;
89   }
90   const RISCVTargetLowering *getTargetLowering() const override {
91     return &TLInfo;
92   }
93   const SelectionDAGTargetInfo *getSelectionDAGInfo() const override {
94     return &TSInfo;
95   }
96   bool enableMachineScheduler() const override { return true; }
97 
98   /// Returns RISCV processor family.
99   /// Avoid this function! CPU specifics should be kept local to this class
100   /// and preferably modeled with SubtargetFeatures or properties in
101   /// initializeProperties().
102   RISCVProcFamilyEnum getProcFamily() const { return RISCVProcFamily; }
103 
104 #define GET_SUBTARGETINFO_MACRO(ATTRIBUTE, DEFAULT, GETTER) \
105   bool GETTER() const { return ATTRIBUTE; }
106 #include "RISCVGenSubtargetInfo.inc"
107 
108   bool hasStdExtCOrZca() const { return HasStdExtC || HasStdExtZca; }
109   bool hasStdExtZvl() const { return ZvlLen != 0; }
110   bool hasStdExtZfhOrZfhmin() const { return HasStdExtZfh || HasStdExtZfhmin; }
111   bool is64Bit() const { return HasRV64; }
112   MVT getXLenVT() const { return XLenVT; }
113   unsigned getXLen() const { return XLen; }
114   unsigned getFLen() const {
115     if (HasStdExtD)
116       return 64;
117 
118     if (HasStdExtF)
119       return 32;
120 
121     return 0;
122   }
123   unsigned getELEN() const {
124     assert(hasVInstructions() && "Expected V extension");
125     return hasVInstructionsI64() ? 64 : 32;
126   }
127   unsigned getRealMinVLen() const {
128     unsigned VLen = getMinRVVVectorSizeInBits();
129     return VLen == 0 ? ZvlLen : VLen;
130   }
131   unsigned getRealMaxVLen() const {
132     unsigned VLen = getMaxRVVVectorSizeInBits();
133     return VLen == 0 ? 65536 : VLen;
134   }
135   RISCVABI::ABI getTargetABI() const { return TargetABI; }
136   bool isRegisterReservedByUser(Register i) const {
137     assert(i < RISCV::NUM_TARGET_REGS && "Register out of range");
138     return UserReservedRegister[i];
139   }
140 
141   bool hasMacroFusion() const { return hasLUIADDIFusion(); }
142 
143   // Vector codegen related methods.
144   bool hasVInstructions() const { return HasStdExtZve32x; }
145   bool hasVInstructionsI64() const { return HasStdExtZve64x; }
146   bool hasVInstructionsF16() const {
147     return HasStdExtZvfh && hasStdExtZfhOrZfhmin();
148   }
149   // FIXME: Consider Zfinx in the future
150   bool hasVInstructionsF32() const { return HasStdExtZve32f && HasStdExtF; }
151   // FIXME: Consider Zdinx in the future
152   bool hasVInstructionsF64() const { return HasStdExtZve64d && HasStdExtD; }
153   // F16 and F64 both require F32.
154   bool hasVInstructionsAnyF() const { return hasVInstructionsF32(); }
155   unsigned getMaxInterleaveFactor() const {
156     return hasVInstructions() ? MaxInterleaveFactor : 1;
157   }
158 
159 protected:
160   // GlobalISel related APIs.
161   std::unique_ptr<CallLowering> CallLoweringInfo;
162   std::unique_ptr<InstructionSelector> InstSelector;
163   std::unique_ptr<LegalizerInfo> Legalizer;
164   std::unique_ptr<RegisterBankInfo> RegBankInfo;
165 
166   // Return the known range for the bit length of RVV data registers as set
167   // at the command line. A value of 0 means nothing is known about that particular
168   // limit beyond what's implied by the architecture.
169   // NOTE: Please use getRealMinVLen and getRealMaxVLen instead!
170   unsigned getMaxRVVVectorSizeInBits() const;
171   unsigned getMinRVVVectorSizeInBits() const;
172 
173 public:
174   const CallLowering *getCallLowering() const override;
175   InstructionSelector *getInstructionSelector() const override;
176   const LegalizerInfo *getLegalizerInfo() const override;
177   const RegisterBankInfo *getRegBankInfo() const override;
178 
179   bool isTargetFuchsia() const { return getTargetTriple().isOSFuchsia(); }
180 
181   bool useConstantPoolForLargeInts() const;
182 
183   // Maximum cost used for building integers, integers will be put into constant
184   // pool if exceeded.
185   unsigned getMaxBuildIntsCost() const;
186 
187   unsigned getMaxLMULForFixedLengthVectors() const;
188   bool useRVVForFixedLengthVectors() const;
189 
190   bool enableSubRegLiveness() const override;
191 
192   void getPostRAMutations(std::vector<std::unique_ptr<ScheduleDAGMutation>>
193                               &Mutations) const override;
194 };
195 } // End llvm namespace
196 
197 #endif
198