RISCVInstructionSelector.cpp revision 360784 
1//===-- RISCVInstructionSelector.cpp -----------------------------*- 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 implements the targeting of the InstructionSelector class for
10/// RISCV.
11/// \todo This should be generated by TableGen.
12//===----------------------------------------------------------------------===//
13
14#include "RISCVRegisterBankInfo.h"
15#include "RISCVSubtarget.h"
16#include "RISCVTargetMachine.h"
17#include "llvm/CodeGen/GlobalISel/InstructionSelector.h"
18#include "llvm/CodeGen/GlobalISel/InstructionSelectorImpl.h"
19#include "llvm/Support/Debug.h"
20
21#define DEBUG_TYPE "riscv-isel"
22
23using namespace llvm;
24
25#define GET_GLOBALISEL_PREDICATE_BITSET
26#include "RISCVGenGlobalISel.inc"
27#undef GET_GLOBALISEL_PREDICATE_BITSET
28
29namespace {
30
31class RISCVInstructionSelector : public InstructionSelector {
32public:
33  RISCVInstructionSelector(const RISCVTargetMachine &TM,
34                           const RISCVSubtarget &STI,
35                           const RISCVRegisterBankInfo &RBI);
36
37  bool select(MachineInstr &I) override;
38  static const char *getName() { return DEBUG_TYPE; }
39
40private:
41  bool selectImpl(MachineInstr &I, CodeGenCoverage &CoverageInfo) const;
42
43  const RISCVSubtarget &STI;
44  const RISCVInstrInfo &TII;
45  const RISCVRegisterInfo &TRI;
46  const RISCVRegisterBankInfo &RBI;
47
48  // FIXME: This is necessary because DAGISel uses "Subtarget->" and GlobalISel
49  // uses "STI." in the code generated by TableGen. We need to unify the name of
50  // Subtarget variable.
51  const RISCVSubtarget *Subtarget = &STI;
52
53#define GET_GLOBALISEL_PREDICATES_DECL
54#include "RISCVGenGlobalISel.inc"
55#undef GET_GLOBALISEL_PREDICATES_DECL
56
57#define GET_GLOBALISEL_TEMPORARIES_DECL
58#include "RISCVGenGlobalISel.inc"
59#undef GET_GLOBALISEL_TEMPORARIES_DECL
60};
61
62} // end anonymous namespace
63
64#define GET_GLOBALISEL_IMPL
65#include "RISCVGenGlobalISel.inc"
66#undef GET_GLOBALISEL_IMPL
67
68RISCVInstructionSelector::RISCVInstructionSelector(
69    const RISCVTargetMachine &TM, const RISCVSubtarget &STI,
70    const RISCVRegisterBankInfo &RBI)
71    : InstructionSelector(), STI(STI), TII(*STI.getInstrInfo()),
72      TRI(*STI.getRegisterInfo()), RBI(RBI),
73
74#define GET_GLOBALISEL_PREDICATES_INIT
75#include "RISCVGenGlobalISel.inc"
76#undef GET_GLOBALISEL_PREDICATES_INIT
77#define GET_GLOBALISEL_TEMPORARIES_INIT
78#include "RISCVGenGlobalISel.inc"
79#undef GET_GLOBALISEL_TEMPORARIES_INIT
80{
81}
82
83bool RISCVInstructionSelector::select(MachineInstr &I) {
84
85  if (!isPreISelGenericOpcode(I.getOpcode())) {
86    // Certain non-generic instructions also need some special handling.
87    return true;
88  }
89
90  if (selectImpl(I, *CoverageInfo))
91    return true;
92
93  return false;
94}
95
96namespace llvm {
97InstructionSelector *
98createRISCVInstructionSelector(const RISCVTargetMachine &TM,
99                               RISCVSubtarget &Subtarget,
100                               RISCVRegisterBankInfo &RBI) {
101  return new RISCVInstructionSelector(TM, Subtarget, RBI);
102}
103} // end namespace llvm
104