xref: /freebsd/contrib/llvm-project/llvm/lib/Target/VE/MCTargetDesc/VEMCCodeEmitter.cpp (revision 7ef62cebc2f965b0f640263e179276928885e33d)
1 //===-- VEMCCodeEmitter.cpp - Convert VE code to machine code -------------===//
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 implements the VEMCCodeEmitter class.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "MCTargetDesc/VEFixupKinds.h"
14 #include "VE.h"
15 #include "VEMCExpr.h"
16 #include "llvm/ADT/SmallVector.h"
17 #include "llvm/ADT/Statistic.h"
18 #include "llvm/MC/MCCodeEmitter.h"
19 #include "llvm/MC/MCContext.h"
20 #include "llvm/MC/MCExpr.h"
21 #include "llvm/MC/MCFixup.h"
22 #include "llvm/MC/MCInst.h"
23 #include "llvm/MC/MCInstrInfo.h"
24 #include "llvm/MC/MCRegisterInfo.h"
25 #include "llvm/MC/MCSubtargetInfo.h"
26 #include "llvm/MC/MCSymbol.h"
27 #include "llvm/Support/EndianStream.h"
28 #include "llvm/Support/ErrorHandling.h"
29 #include "llvm/Support/raw_ostream.h"
30 #include <cassert>
31 #include <cstdint>
32 
33 using namespace llvm;
34 
35 #define DEBUG_TYPE "mccodeemitter"
36 
37 STATISTIC(MCNumEmitted, "Number of MC instructions emitted");
38 
39 namespace {
40 
41 class VEMCCodeEmitter : public MCCodeEmitter {
42   MCContext &Ctx;
43 
44 public:
45   VEMCCodeEmitter(const MCInstrInfo &, MCContext &ctx)
46       : Ctx(ctx) {}
47   VEMCCodeEmitter(const VEMCCodeEmitter &) = delete;
48   VEMCCodeEmitter &operator=(const VEMCCodeEmitter &) = delete;
49   ~VEMCCodeEmitter() override = default;
50 
51   void encodeInstruction(const MCInst &MI, raw_ostream &OS,
52                          SmallVectorImpl<MCFixup> &Fixups,
53                          const MCSubtargetInfo &STI) const override;
54 
55   // getBinaryCodeForInstr - TableGen'erated function for getting the
56   // binary encoding for an instruction.
57   uint64_t getBinaryCodeForInstr(const MCInst &MI,
58                                  SmallVectorImpl<MCFixup> &Fixups,
59                                  const MCSubtargetInfo &STI) const;
60 
61   /// getMachineOpValue - Return binary encoding of operand. If the machine
62   /// operand requires relocation, record the relocation and return zero.
63   unsigned getMachineOpValue(const MCInst &MI, const MCOperand &MO,
64                              SmallVectorImpl<MCFixup> &Fixups,
65                              const MCSubtargetInfo &STI) const;
66 
67   uint64_t getBranchTargetOpValue(const MCInst &MI, unsigned OpNo,
68                                   SmallVectorImpl<MCFixup> &Fixups,
69                                   const MCSubtargetInfo &STI) const;
70   uint64_t getCCOpValue(const MCInst &MI, unsigned OpNo,
71                         SmallVectorImpl<MCFixup> &Fixups,
72                         const MCSubtargetInfo &STI) const;
73   uint64_t getRDOpValue(const MCInst &MI, unsigned OpNo,
74                         SmallVectorImpl<MCFixup> &Fixups,
75                         const MCSubtargetInfo &STI) const;
76 };
77 
78 } // end anonymous namespace
79 
80 void VEMCCodeEmitter::encodeInstruction(const MCInst &MI, raw_ostream &OS,
81                                         SmallVectorImpl<MCFixup> &Fixups,
82                                         const MCSubtargetInfo &STI) const {
83   uint64_t Bits = getBinaryCodeForInstr(MI, Fixups, STI);
84   support::endian::write<uint64_t>(OS, Bits, support::little);
85 
86   ++MCNumEmitted; // Keep track of the # of mi's emitted.
87 }
88 
89 unsigned VEMCCodeEmitter::getMachineOpValue(const MCInst &MI,
90                                             const MCOperand &MO,
91                                             SmallVectorImpl<MCFixup> &Fixups,
92                                             const MCSubtargetInfo &STI) const {
93   if (MO.isReg())
94     return Ctx.getRegisterInfo()->getEncodingValue(MO.getReg());
95   if (MO.isImm())
96     return static_cast<unsigned>(MO.getImm());
97 
98   assert(MO.isExpr());
99 
100   const MCExpr *Expr = MO.getExpr();
101   if (const VEMCExpr *SExpr = dyn_cast<VEMCExpr>(Expr)) {
102     MCFixupKind Kind = (MCFixupKind)SExpr->getFixupKind();
103     Fixups.push_back(MCFixup::create(0, Expr, Kind));
104     return 0;
105   }
106 
107   int64_t Res;
108   if (Expr->evaluateAsAbsolute(Res))
109     return Res;
110 
111   llvm_unreachable("Unhandled expression!");
112   return 0;
113 }
114 
115 uint64_t
116 VEMCCodeEmitter::getBranchTargetOpValue(const MCInst &MI, unsigned OpNo,
117                                         SmallVectorImpl<MCFixup> &Fixups,
118                                         const MCSubtargetInfo &STI) const {
119   const MCOperand &MO = MI.getOperand(OpNo);
120   if (MO.isReg() || MO.isImm())
121     return getMachineOpValue(MI, MO, Fixups, STI);
122 
123   Fixups.push_back(
124       MCFixup::create(0, MO.getExpr(), (MCFixupKind)VE::fixup_ve_srel32));
125   return 0;
126 }
127 
128 uint64_t VEMCCodeEmitter::getCCOpValue(const MCInst &MI, unsigned OpNo,
129                                        SmallVectorImpl<MCFixup> &Fixups,
130                                        const MCSubtargetInfo &STI) const {
131   const MCOperand &MO = MI.getOperand(OpNo);
132   if (MO.isImm())
133     return VECondCodeToVal(
134         static_cast<VECC::CondCode>(getMachineOpValue(MI, MO, Fixups, STI)));
135   return 0;
136 }
137 
138 uint64_t VEMCCodeEmitter::getRDOpValue(const MCInst &MI, unsigned OpNo,
139                                        SmallVectorImpl<MCFixup> &Fixups,
140                                        const MCSubtargetInfo &STI) const {
141   const MCOperand &MO = MI.getOperand(OpNo);
142   if (MO.isImm())
143     return VERDToVal(static_cast<VERD::RoundingMode>(
144         getMachineOpValue(MI, MO, Fixups, STI)));
145   return 0;
146 }
147 
148 #include "VEGenMCCodeEmitter.inc"
149 
150 MCCodeEmitter *llvm::createVEMCCodeEmitter(const MCInstrInfo &MCII,
151                                            MCContext &Ctx) {
152   return new VEMCCodeEmitter(MCII, Ctx);
153 }
154