1 //===-- SystemZMCCodeEmitter.cpp - Convert SystemZ 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 SystemZMCCodeEmitter class. 10 // 11 //===----------------------------------------------------------------------===// 12 13 #include "MCTargetDesc/SystemZMCFixups.h" 14 #include "MCTargetDesc/SystemZMCTargetDesc.h" 15 #include "llvm/ADT/SmallVector.h" 16 #include "llvm/MC/MCCodeEmitter.h" 17 #include "llvm/MC/MCContext.h" 18 #include "llvm/MC/MCExpr.h" 19 #include "llvm/MC/MCFixup.h" 20 #include "llvm/MC/MCInst.h" 21 #include "llvm/MC/MCInstrInfo.h" 22 #include "llvm/MC/MCRegisterInfo.h" 23 #include "llvm/MC/MCSubtargetInfo.h" 24 #include "llvm/Support/ErrorHandling.h" 25 #include "llvm/Support/raw_ostream.h" 26 #include <cassert> 27 #include <cstdint> 28 29 using namespace llvm; 30 31 #define DEBUG_TYPE "mccodeemitter" 32 33 namespace { 34 35 class SystemZMCCodeEmitter : public MCCodeEmitter { 36 const MCInstrInfo &MCII; 37 MCContext &Ctx; 38 39 public: 40 SystemZMCCodeEmitter(const MCInstrInfo &mcii, MCContext &ctx) 41 : MCII(mcii), Ctx(ctx) { 42 } 43 44 ~SystemZMCCodeEmitter() override = default; 45 46 // OVerride MCCodeEmitter. 47 void encodeInstruction(const MCInst &MI, raw_ostream &OS, 48 SmallVectorImpl<MCFixup> &Fixups, 49 const MCSubtargetInfo &STI) const override; 50 51 private: 52 // Automatically generated by TableGen. 53 uint64_t getBinaryCodeForInstr(const MCInst &MI, 54 SmallVectorImpl<MCFixup> &Fixups, 55 const MCSubtargetInfo &STI) const; 56 57 // Called by the TableGen code to get the binary encoding of operand 58 // MO in MI. Fixups is the list of fixups against MI. 59 uint64_t getMachineOpValue(const MCInst &MI, const MCOperand &MO, 60 SmallVectorImpl<MCFixup> &Fixups, 61 const MCSubtargetInfo &STI) const; 62 63 // Called by the TableGen code to get the binary encoding of an address. 64 // The index or length, if any, is encoded first, followed by the base, 65 // followed by the displacement. In a 20-bit displacement, 66 // the low 12 bits are encoded before the high 8 bits. 67 uint64_t getBDAddr12Encoding(const MCInst &MI, unsigned OpNum, 68 SmallVectorImpl<MCFixup> &Fixups, 69 const MCSubtargetInfo &STI) const; 70 uint64_t getBDAddr20Encoding(const MCInst &MI, unsigned OpNum, 71 SmallVectorImpl<MCFixup> &Fixups, 72 const MCSubtargetInfo &STI) const; 73 uint64_t getBDXAddr12Encoding(const MCInst &MI, unsigned OpNum, 74 SmallVectorImpl<MCFixup> &Fixups, 75 const MCSubtargetInfo &STI) const; 76 uint64_t getBDXAddr20Encoding(const MCInst &MI, unsigned OpNum, 77 SmallVectorImpl<MCFixup> &Fixups, 78 const MCSubtargetInfo &STI) const; 79 uint64_t getBDLAddr12Len4Encoding(const MCInst &MI, unsigned OpNum, 80 SmallVectorImpl<MCFixup> &Fixups, 81 const MCSubtargetInfo &STI) const; 82 uint64_t getBDLAddr12Len8Encoding(const MCInst &MI, unsigned OpNum, 83 SmallVectorImpl<MCFixup> &Fixups, 84 const MCSubtargetInfo &STI) const; 85 uint64_t getBDRAddr12Encoding(const MCInst &MI, unsigned OpNum, 86 SmallVectorImpl<MCFixup> &Fixups, 87 const MCSubtargetInfo &STI) const; 88 uint64_t getBDVAddr12Encoding(const MCInst &MI, unsigned OpNum, 89 SmallVectorImpl<MCFixup> &Fixups, 90 const MCSubtargetInfo &STI) const; 91 92 // Operand OpNum of MI needs a PC-relative fixup of kind Kind at 93 // Offset bytes from the start of MI. Add the fixup to Fixups 94 // and return the in-place addend, which since we're a RELA target 95 // is always 0. If AllowTLS is true and optional operand OpNum + 1 96 // is present, also emit a TLS call fixup for it. 97 uint64_t getPCRelEncoding(const MCInst &MI, unsigned OpNum, 98 SmallVectorImpl<MCFixup> &Fixups, 99 unsigned Kind, int64_t Offset, 100 bool AllowTLS) const; 101 102 uint64_t getPC16DBLEncoding(const MCInst &MI, unsigned OpNum, 103 SmallVectorImpl<MCFixup> &Fixups, 104 const MCSubtargetInfo &STI) const { 105 return getPCRelEncoding(MI, OpNum, Fixups, 106 SystemZ::FK_390_PC16DBL, 2, false); 107 } 108 uint64_t getPC32DBLEncoding(const MCInst &MI, unsigned OpNum, 109 SmallVectorImpl<MCFixup> &Fixups, 110 const MCSubtargetInfo &STI) const { 111 return getPCRelEncoding(MI, OpNum, Fixups, 112 SystemZ::FK_390_PC32DBL, 2, false); 113 } 114 uint64_t getPC16DBLTLSEncoding(const MCInst &MI, unsigned OpNum, 115 SmallVectorImpl<MCFixup> &Fixups, 116 const MCSubtargetInfo &STI) const { 117 return getPCRelEncoding(MI, OpNum, Fixups, 118 SystemZ::FK_390_PC16DBL, 2, true); 119 } 120 uint64_t getPC32DBLTLSEncoding(const MCInst &MI, unsigned OpNum, 121 SmallVectorImpl<MCFixup> &Fixups, 122 const MCSubtargetInfo &STI) const { 123 return getPCRelEncoding(MI, OpNum, Fixups, 124 SystemZ::FK_390_PC32DBL, 2, true); 125 } 126 uint64_t getPC12DBLBPPEncoding(const MCInst &MI, unsigned OpNum, 127 SmallVectorImpl<MCFixup> &Fixups, 128 const MCSubtargetInfo &STI) const { 129 return getPCRelEncoding(MI, OpNum, Fixups, 130 SystemZ::FK_390_PC12DBL, 1, false); 131 } 132 uint64_t getPC16DBLBPPEncoding(const MCInst &MI, unsigned OpNum, 133 SmallVectorImpl<MCFixup> &Fixups, 134 const MCSubtargetInfo &STI) const { 135 return getPCRelEncoding(MI, OpNum, Fixups, 136 SystemZ::FK_390_PC16DBL, 4, false); 137 } 138 uint64_t getPC24DBLBPPEncoding(const MCInst &MI, unsigned OpNum, 139 SmallVectorImpl<MCFixup> &Fixups, 140 const MCSubtargetInfo &STI) const { 141 return getPCRelEncoding(MI, OpNum, Fixups, 142 SystemZ::FK_390_PC24DBL, 3, false); 143 } 144 145 private: 146 FeatureBitset computeAvailableFeatures(const FeatureBitset &FB) const; 147 void 148 verifyInstructionPredicates(const MCInst &MI, 149 const FeatureBitset &AvailableFeatures) const; 150 }; 151 152 } // end anonymous namespace 153 154 void SystemZMCCodeEmitter:: 155 encodeInstruction(const MCInst &MI, raw_ostream &OS, 156 SmallVectorImpl<MCFixup> &Fixups, 157 const MCSubtargetInfo &STI) const { 158 verifyInstructionPredicates(MI, 159 computeAvailableFeatures(STI.getFeatureBits())); 160 161 uint64_t Bits = getBinaryCodeForInstr(MI, Fixups, STI); 162 unsigned Size = MCII.get(MI.getOpcode()).getSize(); 163 // Big-endian insertion of Size bytes. 164 unsigned ShiftValue = (Size * 8) - 8; 165 for (unsigned I = 0; I != Size; ++I) { 166 OS << uint8_t(Bits >> ShiftValue); 167 ShiftValue -= 8; 168 } 169 } 170 171 uint64_t SystemZMCCodeEmitter:: 172 getMachineOpValue(const MCInst &MI, const MCOperand &MO, 173 SmallVectorImpl<MCFixup> &Fixups, 174 const MCSubtargetInfo &STI) const { 175 if (MO.isReg()) 176 return Ctx.getRegisterInfo()->getEncodingValue(MO.getReg()); 177 if (MO.isImm()) 178 return static_cast<uint64_t>(MO.getImm()); 179 llvm_unreachable("Unexpected operand type!"); 180 } 181 182 uint64_t SystemZMCCodeEmitter:: 183 getBDAddr12Encoding(const MCInst &MI, unsigned OpNum, 184 SmallVectorImpl<MCFixup> &Fixups, 185 const MCSubtargetInfo &STI) const { 186 uint64_t Base = getMachineOpValue(MI, MI.getOperand(OpNum), Fixups, STI); 187 uint64_t Disp = getMachineOpValue(MI, MI.getOperand(OpNum + 1), Fixups, STI); 188 assert(isUInt<4>(Base) && isUInt<12>(Disp)); 189 return (Base << 12) | Disp; 190 } 191 192 uint64_t SystemZMCCodeEmitter:: 193 getBDAddr20Encoding(const MCInst &MI, unsigned OpNum, 194 SmallVectorImpl<MCFixup> &Fixups, 195 const MCSubtargetInfo &STI) const { 196 uint64_t Base = getMachineOpValue(MI, MI.getOperand(OpNum), Fixups, STI); 197 uint64_t Disp = getMachineOpValue(MI, MI.getOperand(OpNum + 1), Fixups, STI); 198 assert(isUInt<4>(Base) && isInt<20>(Disp)); 199 return (Base << 20) | ((Disp & 0xfff) << 8) | ((Disp & 0xff000) >> 12); 200 } 201 202 uint64_t SystemZMCCodeEmitter:: 203 getBDXAddr12Encoding(const MCInst &MI, unsigned OpNum, 204 SmallVectorImpl<MCFixup> &Fixups, 205 const MCSubtargetInfo &STI) const { 206 uint64_t Base = getMachineOpValue(MI, MI.getOperand(OpNum), Fixups, STI); 207 uint64_t Disp = getMachineOpValue(MI, MI.getOperand(OpNum + 1), Fixups, STI); 208 uint64_t Index = getMachineOpValue(MI, MI.getOperand(OpNum + 2), Fixups, STI); 209 assert(isUInt<4>(Base) && isUInt<12>(Disp) && isUInt<4>(Index)); 210 return (Index << 16) | (Base << 12) | Disp; 211 } 212 213 uint64_t SystemZMCCodeEmitter:: 214 getBDXAddr20Encoding(const MCInst &MI, unsigned OpNum, 215 SmallVectorImpl<MCFixup> &Fixups, 216 const MCSubtargetInfo &STI) const { 217 uint64_t Base = getMachineOpValue(MI, MI.getOperand(OpNum), Fixups, STI); 218 uint64_t Disp = getMachineOpValue(MI, MI.getOperand(OpNum + 1), Fixups, STI); 219 uint64_t Index = getMachineOpValue(MI, MI.getOperand(OpNum + 2), Fixups, STI); 220 assert(isUInt<4>(Base) && isInt<20>(Disp) && isUInt<4>(Index)); 221 return (Index << 24) | (Base << 20) | ((Disp & 0xfff) << 8) 222 | ((Disp & 0xff000) >> 12); 223 } 224 225 uint64_t SystemZMCCodeEmitter:: 226 getBDLAddr12Len4Encoding(const MCInst &MI, unsigned OpNum, 227 SmallVectorImpl<MCFixup> &Fixups, 228 const MCSubtargetInfo &STI) const { 229 uint64_t Base = getMachineOpValue(MI, MI.getOperand(OpNum), Fixups, STI); 230 uint64_t Disp = getMachineOpValue(MI, MI.getOperand(OpNum + 1), Fixups, STI); 231 uint64_t Len = getMachineOpValue(MI, MI.getOperand(OpNum + 2), Fixups, STI) - 1; 232 assert(isUInt<4>(Base) && isUInt<12>(Disp) && isUInt<4>(Len)); 233 return (Len << 16) | (Base << 12) | Disp; 234 } 235 236 uint64_t SystemZMCCodeEmitter:: 237 getBDLAddr12Len8Encoding(const MCInst &MI, unsigned OpNum, 238 SmallVectorImpl<MCFixup> &Fixups, 239 const MCSubtargetInfo &STI) const { 240 uint64_t Base = getMachineOpValue(MI, MI.getOperand(OpNum), Fixups, STI); 241 uint64_t Disp = getMachineOpValue(MI, MI.getOperand(OpNum + 1), Fixups, STI); 242 uint64_t Len = getMachineOpValue(MI, MI.getOperand(OpNum + 2), Fixups, STI) - 1; 243 assert(isUInt<4>(Base) && isUInt<12>(Disp) && isUInt<8>(Len)); 244 return (Len << 16) | (Base << 12) | Disp; 245 } 246 247 uint64_t SystemZMCCodeEmitter:: 248 getBDRAddr12Encoding(const MCInst &MI, unsigned OpNum, 249 SmallVectorImpl<MCFixup> &Fixups, 250 const MCSubtargetInfo &STI) const { 251 uint64_t Base = getMachineOpValue(MI, MI.getOperand(OpNum), Fixups, STI); 252 uint64_t Disp = getMachineOpValue(MI, MI.getOperand(OpNum + 1), Fixups, STI); 253 uint64_t Len = getMachineOpValue(MI, MI.getOperand(OpNum + 2), Fixups, STI); 254 assert(isUInt<4>(Base) && isUInt<12>(Disp) && isUInt<4>(Len)); 255 return (Len << 16) | (Base << 12) | Disp; 256 } 257 258 uint64_t SystemZMCCodeEmitter:: 259 getBDVAddr12Encoding(const MCInst &MI, unsigned OpNum, 260 SmallVectorImpl<MCFixup> &Fixups, 261 const MCSubtargetInfo &STI) const { 262 uint64_t Base = getMachineOpValue(MI, MI.getOperand(OpNum), Fixups, STI); 263 uint64_t Disp = getMachineOpValue(MI, MI.getOperand(OpNum + 1), Fixups, STI); 264 uint64_t Index = getMachineOpValue(MI, MI.getOperand(OpNum + 2), Fixups, STI); 265 assert(isUInt<4>(Base) && isUInt<12>(Disp) && isUInt<5>(Index)); 266 return (Index << 16) | (Base << 12) | Disp; 267 } 268 269 uint64_t 270 SystemZMCCodeEmitter::getPCRelEncoding(const MCInst &MI, unsigned OpNum, 271 SmallVectorImpl<MCFixup> &Fixups, 272 unsigned Kind, int64_t Offset, 273 bool AllowTLS) const { 274 const MCOperand &MO = MI.getOperand(OpNum); 275 const MCExpr *Expr; 276 if (MO.isImm()) 277 Expr = MCConstantExpr::create(MO.getImm() + Offset, Ctx); 278 else { 279 Expr = MO.getExpr(); 280 if (Offset) { 281 // The operand value is relative to the start of MI, but the fixup 282 // is relative to the operand field itself, which is Offset bytes 283 // into MI. Add Offset to the relocation value to cancel out 284 // this difference. 285 const MCExpr *OffsetExpr = MCConstantExpr::create(Offset, Ctx); 286 Expr = MCBinaryExpr::createAdd(Expr, OffsetExpr, Ctx); 287 } 288 } 289 Fixups.push_back(MCFixup::create(Offset, Expr, (MCFixupKind)Kind)); 290 291 // Output the fixup for the TLS marker if present. 292 if (AllowTLS && OpNum + 1 < MI.getNumOperands()) { 293 const MCOperand &MOTLS = MI.getOperand(OpNum + 1); 294 Fixups.push_back(MCFixup::create(0, MOTLS.getExpr(), 295 (MCFixupKind)SystemZ::FK_390_TLS_CALL)); 296 } 297 return 0; 298 } 299 300 #define ENABLE_INSTR_PREDICATE_VERIFIER 301 #include "SystemZGenMCCodeEmitter.inc" 302 303 MCCodeEmitter *llvm::createSystemZMCCodeEmitter(const MCInstrInfo &MCII, 304 const MCRegisterInfo &MRI, 305 MCContext &Ctx) { 306 return new SystemZMCCodeEmitter(MCII, Ctx); 307 } 308