xref: /freebsd/contrib/llvm-project/llvm/lib/Target/CSKY/MCTargetDesc/CSKYMCCodeEmitter.cpp (revision 8ddb146abcdf061be9f2c0db7e391697dafad85c)
1 //===-- CSKYMCCodeEmitter.cpp - CSKY Code Emitter interface ---------------===//
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 CSKYMCCodeEmitter class.
10 //
11 //===----------------------------------------------------------------------===//
12 
13 #include "CSKYMCCodeEmitter.h"
14 #include "CSKYMCExpr.h"
15 #include "MCTargetDesc/CSKYMCTargetDesc.h"
16 #include "llvm/ADT/Statistic.h"
17 #include "llvm/MC/MCInstBuilder.h"
18 #include "llvm/MC/MCInstrInfo.h"
19 #include "llvm/Support/EndianStream.h"
20 
21 using namespace llvm;
22 
23 #define DEBUG_TYPE "csky-mccode-emitter"
24 
25 STATISTIC(MCNumEmitted, "Number of MC instructions emitted");
26 
27 unsigned CSKYMCCodeEmitter::getOImmOpValue(const MCInst &MI, unsigned Idx,
28                                            SmallVectorImpl<MCFixup> &Fixups,
29                                            const MCSubtargetInfo &STI) const {
30   const MCOperand &MO = MI.getOperand(Idx);
31   assert(MO.isImm() && "Unexpected MO type.");
32   return MO.getImm() - 1;
33 }
34 
35 unsigned
36 CSKYMCCodeEmitter::getImmOpValueIDLY(const MCInst &MI, unsigned Idx,
37                                      SmallVectorImpl<MCFixup> &Fixups,
38                                      const MCSubtargetInfo &STI) const {
39   const MCOperand &MO = MI.getOperand(Idx);
40   assert(MO.isImm() && "Unexpected MO type.");
41 
42   auto V = (MO.getImm() <= 3) ? 4 : MO.getImm();
43   return V - 1;
44 }
45 
46 unsigned
47 CSKYMCCodeEmitter::getImmOpValueMSBSize(const MCInst &MI, unsigned Idx,
48                                         SmallVectorImpl<MCFixup> &Fixups,
49                                         const MCSubtargetInfo &STI) const {
50   const MCOperand &MSB = MI.getOperand(Idx);
51   const MCOperand &LSB = MI.getOperand(Idx + 1);
52   assert(MSB.isImm() && LSB.isImm() && "Unexpected MO type.");
53 
54   return MSB.getImm() - LSB.getImm();
55 }
56 
57 static void writeData(uint32_t Bin, unsigned Size, raw_ostream &OS) {
58   uint16_t LO16 = static_cast<uint16_t>(Bin);
59   uint16_t HI16 = static_cast<uint16_t>(Bin >> 16);
60 
61   if (Size == 4)
62     support::endian::write<uint16_t>(OS, HI16, support::little);
63 
64   support::endian::write<uint16_t>(OS, LO16, support::little);
65 }
66 
67 void CSKYMCCodeEmitter::encodeInstruction(const MCInst &MI, raw_ostream &OS,
68                                           SmallVectorImpl<MCFixup> &Fixups,
69                                           const MCSubtargetInfo &STI) const {
70   const MCInstrDesc &Desc = MII.get(MI.getOpcode());
71   unsigned Size = Desc.getSize();
72 
73   ++MCNumEmitted;
74 
75   uint32_t Bin = getBinaryCodeForInstr(MI, Fixups, STI);
76 
77   uint16_t LO16 = static_cast<uint16_t>(Bin);
78   uint16_t HI16 = static_cast<uint16_t>(Bin >> 16);
79 
80   if (Size == 4)
81     support::endian::write<uint16_t>(OS, HI16, support::little);
82 
83   support::endian::write<uint16_t>(OS, LO16, support::little);
84 }
85 
86 unsigned
87 CSKYMCCodeEmitter::getMachineOpValue(const MCInst &MI, const MCOperand &MO,
88                                      SmallVectorImpl<MCFixup> &Fixups,
89                                      const MCSubtargetInfo &STI) const {
90   if (MO.isReg())
91     return Ctx.getRegisterInfo()->getEncodingValue(MO.getReg());
92 
93   if (MO.isImm())
94     return static_cast<unsigned>(MO.getImm());
95 
96   llvm_unreachable("Unhandled expression!");
97   return 0;
98 }
99 
100 unsigned
101 CSKYMCCodeEmitter::getRegSeqImmOpValue(const MCInst &MI, unsigned Idx,
102                                        SmallVectorImpl<MCFixup> &Fixups,
103                                        const MCSubtargetInfo &STI) const {
104   assert(MI.getOperand(Idx).isReg() && "Unexpected MO type.");
105   assert(MI.getOperand(Idx + 1).isImm() && "Unexpected MO type.");
106 
107   unsigned Ry = MI.getOperand(Idx).getReg();
108   unsigned Rz = MI.getOperand(Idx + 1).getImm();
109 
110   unsigned Imm = Ctx.getRegisterInfo()->getEncodingValue(Rz) -
111                  Ctx.getRegisterInfo()->getEncodingValue(Ry);
112 
113   return ((Ctx.getRegisterInfo()->getEncodingValue(Ry) << 5) | Imm);
114 }
115 
116 unsigned
117 CSKYMCCodeEmitter::getRegisterSeqOpValue(const MCInst &MI, unsigned Op,
118                                          SmallVectorImpl<MCFixup> &Fixups,
119                                          const MCSubtargetInfo &STI) const {
120   unsigned Reg1 =
121       Ctx.getRegisterInfo()->getEncodingValue(MI.getOperand(Op).getReg());
122   unsigned Reg2 =
123       Ctx.getRegisterInfo()->getEncodingValue(MI.getOperand(Op + 1).getReg());
124 
125   unsigned Binary = ((Reg1 & 0x1f) << 5) | (Reg2 - Reg1);
126 
127   return Binary;
128 }
129 
130 unsigned CSKYMCCodeEmitter::getImmJMPIX(const MCInst &MI, unsigned Idx,
131                                         SmallVectorImpl<MCFixup> &Fixups,
132                                         const MCSubtargetInfo &STI) const {
133   if (MI.getOperand(Idx).getImm() == 16)
134     return 0;
135   else if (MI.getOperand(Idx).getImm() == 24)
136     return 1;
137   else if (MI.getOperand(Idx).getImm() == 32)
138     return 2;
139   else if (MI.getOperand(Idx).getImm() == 40)
140     return 3;
141   else
142     assert(0);
143 }
144 
145 MCFixupKind CSKYMCCodeEmitter::getTargetFixup(const MCExpr *Expr) const {
146   const CSKYMCExpr *CSKYExpr = cast<CSKYMCExpr>(Expr);
147 
148   switch (CSKYExpr->getKind()) {
149   default:
150     llvm_unreachable("Unhandled fixup kind!");
151   case CSKYMCExpr::VK_CSKY_ADDR:
152     return MCFixupKind(CSKY::fixup_csky_addr32);
153   case CSKYMCExpr::VK_CSKY_ADDR_HI16:
154     return MCFixupKind(CSKY::fixup_csky_addr_hi16);
155   case CSKYMCExpr::VK_CSKY_ADDR_LO16:
156     return MCFixupKind(CSKY::fixup_csky_addr_lo16);
157   case CSKYMCExpr::VK_CSKY_GOT:
158     return MCFixupKind(CSKY::fixup_csky_got32);
159   case CSKYMCExpr::VK_CSKY_GOTPC:
160     return MCFixupKind(CSKY::fixup_csky_gotpc);
161   case CSKYMCExpr::VK_CSKY_GOTOFF:
162     return MCFixupKind(CSKY::fixup_csky_gotoff);
163   case CSKYMCExpr::VK_CSKY_PLT:
164     return MCFixupKind(CSKY::fixup_csky_plt32);
165   case CSKYMCExpr::VK_CSKY_PLT_IMM18_BY4:
166     return MCFixupKind(CSKY::fixup_csky_plt_imm18_scale4);
167   case CSKYMCExpr::VK_CSKY_GOT_IMM18_BY4:
168     return MCFixupKind(CSKY::fixup_csky_got_imm18_scale4);
169   }
170 }
171 
172 MCCodeEmitter *llvm::createCSKYMCCodeEmitter(const MCInstrInfo &MCII,
173                                              const MCRegisterInfo &MRI,
174                                              MCContext &Ctx) {
175   return new CSKYMCCodeEmitter(Ctx, MCII);
176 }
177 
178 #include "CSKYGenMCCodeEmitter.inc"
179