xref: /freebsd/contrib/llvm-project/llvm/lib/Target/VE/MCTargetDesc/VEMCCodeEmitter.cpp (revision aa1a8ff2d6dbc51ef058f46f3db5a8bb77967145)
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, SmallVectorImpl<char> &CB,
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,
81                                         SmallVectorImpl<char> &CB,
82                                         SmallVectorImpl<MCFixup> &Fixups,
83                                         const MCSubtargetInfo &STI) const {
84   uint64_t Bits = getBinaryCodeForInstr(MI, Fixups, STI);
85   support::endian::write<uint64_t>(CB, Bits, llvm::endianness::little);
86 
87   ++MCNumEmitted; // Keep track of the # of mi's emitted.
88 }
89 
90 unsigned VEMCCodeEmitter::getMachineOpValue(const MCInst &MI,
91                                             const MCOperand &MO,
92                                             SmallVectorImpl<MCFixup> &Fixups,
93                                             const MCSubtargetInfo &STI) const {
94   if (MO.isReg())
95     return Ctx.getRegisterInfo()->getEncodingValue(MO.getReg());
96   if (MO.isImm())
97     return static_cast<unsigned>(MO.getImm());
98 
99   assert(MO.isExpr());
100 
101   const MCExpr *Expr = MO.getExpr();
102   if (const VEMCExpr *SExpr = dyn_cast<VEMCExpr>(Expr)) {
103     MCFixupKind Kind = (MCFixupKind)SExpr->getFixupKind();
104     Fixups.push_back(MCFixup::create(0, Expr, Kind));
105     return 0;
106   }
107 
108   int64_t Res;
109   if (Expr->evaluateAsAbsolute(Res))
110     return Res;
111 
112   llvm_unreachable("Unhandled expression!");
113   return 0;
114 }
115 
116 uint64_t
117 VEMCCodeEmitter::getBranchTargetOpValue(const MCInst &MI, unsigned OpNo,
118                                         SmallVectorImpl<MCFixup> &Fixups,
119                                         const MCSubtargetInfo &STI) const {
120   const MCOperand &MO = MI.getOperand(OpNo);
121   if (MO.isReg() || MO.isImm())
122     return getMachineOpValue(MI, MO, Fixups, STI);
123 
124   Fixups.push_back(
125       MCFixup::create(0, MO.getExpr(), (MCFixupKind)VE::fixup_ve_srel32));
126   return 0;
127 }
128 
129 uint64_t VEMCCodeEmitter::getCCOpValue(const MCInst &MI, unsigned OpNo,
130                                        SmallVectorImpl<MCFixup> &Fixups,
131                                        const MCSubtargetInfo &STI) const {
132   const MCOperand &MO = MI.getOperand(OpNo);
133   if (MO.isImm())
134     return VECondCodeToVal(
135         static_cast<VECC::CondCode>(getMachineOpValue(MI, MO, Fixups, STI)));
136   return 0;
137 }
138 
139 uint64_t VEMCCodeEmitter::getRDOpValue(const MCInst &MI, unsigned OpNo,
140                                        SmallVectorImpl<MCFixup> &Fixups,
141                                        const MCSubtargetInfo &STI) const {
142   const MCOperand &MO = MI.getOperand(OpNo);
143   if (MO.isImm())
144     return VERDToVal(static_cast<VERD::RoundingMode>(
145         getMachineOpValue(MI, MO, Fixups, STI)));
146   return 0;
147 }
148 
149 #include "VEGenMCCodeEmitter.inc"
150 
151 MCCodeEmitter *llvm::createVEMCCodeEmitter(const MCInstrInfo &MCII,
152                                            MCContext &Ctx) {
153   return new VEMCCodeEmitter(MCII, Ctx);
154 }
155