xref: /freebsd/contrib/llvm-project/llvm/lib/Target/VE/MCTargetDesc/VEMCCodeEmitter.cpp (revision d5b0e70f7e04d971691517ce1304d86a1e367e2e)
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   const MCInstrInfo &MCII;
43   MCContext &Ctx;
44 
45 public:
46   VEMCCodeEmitter(const MCInstrInfo &mcii, MCContext &ctx)
47       : MCII(mcii), Ctx(ctx) {}
48   VEMCCodeEmitter(const VEMCCodeEmitter &) = delete;
49   VEMCCodeEmitter &operator=(const VEMCCodeEmitter &) = delete;
50   ~VEMCCodeEmitter() override = default;
51 
52   void encodeInstruction(const MCInst &MI, raw_ostream &OS,
53                          SmallVectorImpl<MCFixup> &Fixups,
54                          const MCSubtargetInfo &STI) const override;
55 
56   // getBinaryCodeForInstr - TableGen'erated function for getting the
57   // binary encoding for an instruction.
58   uint64_t getBinaryCodeForInstr(const MCInst &MI,
59                                  SmallVectorImpl<MCFixup> &Fixups,
60                                  const MCSubtargetInfo &STI) const;
61 
62   /// getMachineOpValue - Return binary encoding of operand. If the machine
63   /// operand requires relocation, record the relocation and return zero.
64   unsigned getMachineOpValue(const MCInst &MI, const MCOperand &MO,
65                              SmallVectorImpl<MCFixup> &Fixups,
66                              const MCSubtargetInfo &STI) const;
67 
68   uint64_t getBranchTargetOpValue(const MCInst &MI, unsigned OpNo,
69                                   SmallVectorImpl<MCFixup> &Fixups,
70                                   const MCSubtargetInfo &STI) const;
71   uint64_t getCCOpValue(const MCInst &MI, unsigned OpNo,
72                         SmallVectorImpl<MCFixup> &Fixups,
73                         const MCSubtargetInfo &STI) const;
74   uint64_t getRDOpValue(const MCInst &MI, unsigned OpNo,
75                         SmallVectorImpl<MCFixup> &Fixups,
76                         const MCSubtargetInfo &STI) const;
77 
78 private:
79   FeatureBitset computeAvailableFeatures(const FeatureBitset &FB) const;
80   void
81   verifyInstructionPredicates(const MCInst &MI,
82                               const FeatureBitset &AvailableFeatures) const;
83 };
84 
85 } // end anonymous namespace
86 
87 void VEMCCodeEmitter::encodeInstruction(const MCInst &MI, raw_ostream &OS,
88                                         SmallVectorImpl<MCFixup> &Fixups,
89                                         const MCSubtargetInfo &STI) const {
90   verifyInstructionPredicates(MI,
91                               computeAvailableFeatures(STI.getFeatureBits()));
92 
93   uint64_t Bits = getBinaryCodeForInstr(MI, Fixups, STI);
94   support::endian::write<uint64_t>(OS, Bits, support::little);
95 
96   ++MCNumEmitted; // Keep track of the # of mi's emitted.
97 }
98 
99 unsigned VEMCCodeEmitter::getMachineOpValue(const MCInst &MI,
100                                             const MCOperand &MO,
101                                             SmallVectorImpl<MCFixup> &Fixups,
102                                             const MCSubtargetInfo &STI) const {
103   if (MO.isReg())
104     return Ctx.getRegisterInfo()->getEncodingValue(MO.getReg());
105   if (MO.isImm())
106     return static_cast<unsigned>(MO.getImm());
107 
108   assert(MO.isExpr());
109 
110   const MCExpr *Expr = MO.getExpr();
111   if (const VEMCExpr *SExpr = dyn_cast<VEMCExpr>(Expr)) {
112     MCFixupKind Kind = (MCFixupKind)SExpr->getFixupKind();
113     Fixups.push_back(MCFixup::create(0, Expr, Kind));
114     return 0;
115   }
116 
117   int64_t Res;
118   if (Expr->evaluateAsAbsolute(Res))
119     return Res;
120 
121   llvm_unreachable("Unhandled expression!");
122   return 0;
123 }
124 
125 uint64_t
126 VEMCCodeEmitter::getBranchTargetOpValue(const MCInst &MI, unsigned OpNo,
127                                         SmallVectorImpl<MCFixup> &Fixups,
128                                         const MCSubtargetInfo &STI) const {
129   const MCOperand &MO = MI.getOperand(OpNo);
130   if (MO.isReg() || MO.isImm())
131     return getMachineOpValue(MI, MO, Fixups, STI);
132 
133   Fixups.push_back(
134       MCFixup::create(0, MO.getExpr(), (MCFixupKind)VE::fixup_ve_srel32));
135   return 0;
136 }
137 
138 uint64_t VEMCCodeEmitter::getCCOpValue(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 VECondCodeToVal(
144         static_cast<VECC::CondCode>(getMachineOpValue(MI, MO, Fixups, STI)));
145   return 0;
146 }
147 
148 uint64_t VEMCCodeEmitter::getRDOpValue(const MCInst &MI, unsigned OpNo,
149                                        SmallVectorImpl<MCFixup> &Fixups,
150                                        const MCSubtargetInfo &STI) const {
151   const MCOperand &MO = MI.getOperand(OpNo);
152   if (MO.isImm())
153     return VERDToVal(static_cast<VERD::RoundingMode>(
154         getMachineOpValue(MI, MO, Fixups, STI)));
155   return 0;
156 }
157 
158 #define ENABLE_INSTR_PREDICATE_VERIFIER
159 #include "VEGenMCCodeEmitter.inc"
160 
161 MCCodeEmitter *llvm::createVEMCCodeEmitter(const MCInstrInfo &MCII,
162                                            const MCRegisterInfo &MRI,
163                                            MCContext &Ctx) {
164   return new VEMCCodeEmitter(MCII, Ctx);
165 }
166