ARMISelDAGToDAG.cpp revision 194710
1//===-- ARMISelDAGToDAG.cpp - A dag to dag inst selector for ARM ----------===// 2// 3// The LLVM Compiler Infrastructure 4// 5// This file is distributed under the University of Illinois Open Source 6// License. See LICENSE.TXT for details. 7// 8//===----------------------------------------------------------------------===// 9// 10// This file defines an instruction selector for the ARM target. 11// 12//===----------------------------------------------------------------------===// 13 14#include "ARM.h" 15#include "ARMAddressingModes.h" 16#include "ARMConstantPoolValue.h" 17#include "ARMISelLowering.h" 18#include "ARMTargetMachine.h" 19#include "llvm/CallingConv.h" 20#include "llvm/Constants.h" 21#include "llvm/DerivedTypes.h" 22#include "llvm/Function.h" 23#include "llvm/Intrinsics.h" 24#include "llvm/CodeGen/MachineFrameInfo.h" 25#include "llvm/CodeGen/MachineFunction.h" 26#include "llvm/CodeGen/MachineInstrBuilder.h" 27#include "llvm/CodeGen/SelectionDAG.h" 28#include "llvm/CodeGen/SelectionDAGISel.h" 29#include "llvm/Target/TargetLowering.h" 30#include "llvm/Target/TargetOptions.h" 31#include "llvm/Support/Compiler.h" 32#include "llvm/Support/Debug.h" 33using namespace llvm; 34 35static const unsigned arm_dsubreg_0 = 5; 36static const unsigned arm_dsubreg_1 = 6; 37 38//===--------------------------------------------------------------------===// 39/// ARMDAGToDAGISel - ARM specific code to select ARM machine 40/// instructions for SelectionDAG operations. 41/// 42namespace { 43class ARMDAGToDAGISel : public SelectionDAGISel { 44 ARMTargetMachine &TM; 45 46 /// Subtarget - Keep a pointer to the ARMSubtarget around so that we can 47 /// make the right decision when generating code for different targets. 48 const ARMSubtarget *Subtarget; 49 50public: 51 explicit ARMDAGToDAGISel(ARMTargetMachine &tm) 52 : SelectionDAGISel(tm), TM(tm), 53 Subtarget(&TM.getSubtarget<ARMSubtarget>()) { 54 } 55 56 virtual const char *getPassName() const { 57 return "ARM Instruction Selection"; 58 } 59 60 /// getI32Imm - Return a target constant with the specified value, of type i32. 61 inline SDValue getI32Imm(unsigned Imm) { 62 return CurDAG->getTargetConstant(Imm, MVT::i32); 63 } 64 65 SDNode *Select(SDValue Op); 66 virtual void InstructionSelect(); 67 bool SelectAddrMode2(SDValue Op, SDValue N, SDValue &Base, 68 SDValue &Offset, SDValue &Opc); 69 bool SelectAddrMode2Offset(SDValue Op, SDValue N, 70 SDValue &Offset, SDValue &Opc); 71 bool SelectAddrMode3(SDValue Op, SDValue N, SDValue &Base, 72 SDValue &Offset, SDValue &Opc); 73 bool SelectAddrMode3Offset(SDValue Op, SDValue N, 74 SDValue &Offset, SDValue &Opc); 75 bool SelectAddrMode5(SDValue Op, SDValue N, SDValue &Base, 76 SDValue &Offset); 77 78 bool SelectAddrModePC(SDValue Op, SDValue N, SDValue &Offset, 79 SDValue &Label); 80 81 bool SelectThumbAddrModeRR(SDValue Op, SDValue N, SDValue &Base, 82 SDValue &Offset); 83 bool SelectThumbAddrModeRI5(SDValue Op, SDValue N, unsigned Scale, 84 SDValue &Base, SDValue &OffImm, 85 SDValue &Offset); 86 bool SelectThumbAddrModeS1(SDValue Op, SDValue N, SDValue &Base, 87 SDValue &OffImm, SDValue &Offset); 88 bool SelectThumbAddrModeS2(SDValue Op, SDValue N, SDValue &Base, 89 SDValue &OffImm, SDValue &Offset); 90 bool SelectThumbAddrModeS4(SDValue Op, SDValue N, SDValue &Base, 91 SDValue &OffImm, SDValue &Offset); 92 bool SelectThumbAddrModeSP(SDValue Op, SDValue N, SDValue &Base, 93 SDValue &OffImm); 94 95 bool SelectShifterOperand(SDValue Op, SDValue N, 96 SDValue &BaseReg, SDValue &Opc); 97 98 bool SelectShifterOperandReg(SDValue Op, SDValue N, SDValue &A, 99 SDValue &B, SDValue &C); 100 101 // Include the pieces autogenerated from the target description. 102#include "ARMGenDAGISel.inc" 103 104private: 105 /// SelectInlineAsmMemoryOperand - Implement addressing mode selection for 106 /// inline asm expressions. 107 virtual bool SelectInlineAsmMemoryOperand(const SDValue &Op, 108 char ConstraintCode, 109 std::vector<SDValue> &OutOps); 110}; 111} 112 113void ARMDAGToDAGISel::InstructionSelect() { 114 DEBUG(BB->dump()); 115 116 SelectRoot(*CurDAG); 117 CurDAG->RemoveDeadNodes(); 118} 119 120bool ARMDAGToDAGISel::SelectAddrMode2(SDValue Op, SDValue N, 121 SDValue &Base, SDValue &Offset, 122 SDValue &Opc) { 123 if (N.getOpcode() == ISD::MUL) { 124 if (ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(N.getOperand(1))) { 125 // X * [3,5,9] -> X + X * [2,4,8] etc. 126 int RHSC = (int)RHS->getZExtValue(); 127 if (RHSC & 1) { 128 RHSC = RHSC & ~1; 129 ARM_AM::AddrOpc AddSub = ARM_AM::add; 130 if (RHSC < 0) { 131 AddSub = ARM_AM::sub; 132 RHSC = - RHSC; 133 } 134 if (isPowerOf2_32(RHSC)) { 135 unsigned ShAmt = Log2_32(RHSC); 136 Base = Offset = N.getOperand(0); 137 Opc = CurDAG->getTargetConstant(ARM_AM::getAM2Opc(AddSub, ShAmt, 138 ARM_AM::lsl), 139 MVT::i32); 140 return true; 141 } 142 } 143 } 144 } 145 146 if (N.getOpcode() != ISD::ADD && N.getOpcode() != ISD::SUB) { 147 Base = N; 148 if (N.getOpcode() == ISD::FrameIndex) { 149 int FI = cast<FrameIndexSDNode>(N)->getIndex(); 150 Base = CurDAG->getTargetFrameIndex(FI, TLI.getPointerTy()); 151 } else if (N.getOpcode() == ARMISD::Wrapper) { 152 Base = N.getOperand(0); 153 } 154 Offset = CurDAG->getRegister(0, MVT::i32); 155 Opc = CurDAG->getTargetConstant(ARM_AM::getAM2Opc(ARM_AM::add, 0, 156 ARM_AM::no_shift), 157 MVT::i32); 158 return true; 159 } 160 161 // Match simple R +/- imm12 operands. 162 if (N.getOpcode() == ISD::ADD) 163 if (ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(N.getOperand(1))) { 164 int RHSC = (int)RHS->getZExtValue(); 165 if ((RHSC >= 0 && RHSC < 0x1000) || 166 (RHSC < 0 && RHSC > -0x1000)) { // 12 bits. 167 Base = N.getOperand(0); 168 if (Base.getOpcode() == ISD::FrameIndex) { 169 int FI = cast<FrameIndexSDNode>(Base)->getIndex(); 170 Base = CurDAG->getTargetFrameIndex(FI, TLI.getPointerTy()); 171 } 172 Offset = CurDAG->getRegister(0, MVT::i32); 173 174 ARM_AM::AddrOpc AddSub = ARM_AM::add; 175 if (RHSC < 0) { 176 AddSub = ARM_AM::sub; 177 RHSC = - RHSC; 178 } 179 Opc = CurDAG->getTargetConstant(ARM_AM::getAM2Opc(AddSub, RHSC, 180 ARM_AM::no_shift), 181 MVT::i32); 182 return true; 183 } 184 } 185 186 // Otherwise this is R +/- [possibly shifted] R 187 ARM_AM::AddrOpc AddSub = N.getOpcode() == ISD::ADD ? ARM_AM::add:ARM_AM::sub; 188 ARM_AM::ShiftOpc ShOpcVal = ARM_AM::getShiftOpcForNode(N.getOperand(1)); 189 unsigned ShAmt = 0; 190 191 Base = N.getOperand(0); 192 Offset = N.getOperand(1); 193 194 if (ShOpcVal != ARM_AM::no_shift) { 195 // Check to see if the RHS of the shift is a constant, if not, we can't fold 196 // it. 197 if (ConstantSDNode *Sh = 198 dyn_cast<ConstantSDNode>(N.getOperand(1).getOperand(1))) { 199 ShAmt = Sh->getZExtValue(); 200 Offset = N.getOperand(1).getOperand(0); 201 } else { 202 ShOpcVal = ARM_AM::no_shift; 203 } 204 } 205 206 // Try matching (R shl C) + (R). 207 if (N.getOpcode() == ISD::ADD && ShOpcVal == ARM_AM::no_shift) { 208 ShOpcVal = ARM_AM::getShiftOpcForNode(N.getOperand(0)); 209 if (ShOpcVal != ARM_AM::no_shift) { 210 // Check to see if the RHS of the shift is a constant, if not, we can't 211 // fold it. 212 if (ConstantSDNode *Sh = 213 dyn_cast<ConstantSDNode>(N.getOperand(0).getOperand(1))) { 214 ShAmt = Sh->getZExtValue(); 215 Offset = N.getOperand(0).getOperand(0); 216 Base = N.getOperand(1); 217 } else { 218 ShOpcVal = ARM_AM::no_shift; 219 } 220 } 221 } 222 223 Opc = CurDAG->getTargetConstant(ARM_AM::getAM2Opc(AddSub, ShAmt, ShOpcVal), 224 MVT::i32); 225 return true; 226} 227 228bool ARMDAGToDAGISel::SelectAddrMode2Offset(SDValue Op, SDValue N, 229 SDValue &Offset, SDValue &Opc) { 230 unsigned Opcode = Op.getOpcode(); 231 ISD::MemIndexedMode AM = (Opcode == ISD::LOAD) 232 ? cast<LoadSDNode>(Op)->getAddressingMode() 233 : cast<StoreSDNode>(Op)->getAddressingMode(); 234 ARM_AM::AddrOpc AddSub = (AM == ISD::PRE_INC || AM == ISD::POST_INC) 235 ? ARM_AM::add : ARM_AM::sub; 236 if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(N)) { 237 int Val = (int)C->getZExtValue(); 238 if (Val >= 0 && Val < 0x1000) { // 12 bits. 239 Offset = CurDAG->getRegister(0, MVT::i32); 240 Opc = CurDAG->getTargetConstant(ARM_AM::getAM2Opc(AddSub, Val, 241 ARM_AM::no_shift), 242 MVT::i32); 243 return true; 244 } 245 } 246 247 Offset = N; 248 ARM_AM::ShiftOpc ShOpcVal = ARM_AM::getShiftOpcForNode(N); 249 unsigned ShAmt = 0; 250 if (ShOpcVal != ARM_AM::no_shift) { 251 // Check to see if the RHS of the shift is a constant, if not, we can't fold 252 // it. 253 if (ConstantSDNode *Sh = dyn_cast<ConstantSDNode>(N.getOperand(1))) { 254 ShAmt = Sh->getZExtValue(); 255 Offset = N.getOperand(0); 256 } else { 257 ShOpcVal = ARM_AM::no_shift; 258 } 259 } 260 261 Opc = CurDAG->getTargetConstant(ARM_AM::getAM2Opc(AddSub, ShAmt, ShOpcVal), 262 MVT::i32); 263 return true; 264} 265 266 267bool ARMDAGToDAGISel::SelectAddrMode3(SDValue Op, SDValue N, 268 SDValue &Base, SDValue &Offset, 269 SDValue &Opc) { 270 if (N.getOpcode() == ISD::SUB) { 271 // X - C is canonicalize to X + -C, no need to handle it here. 272 Base = N.getOperand(0); 273 Offset = N.getOperand(1); 274 Opc = CurDAG->getTargetConstant(ARM_AM::getAM3Opc(ARM_AM::sub, 0),MVT::i32); 275 return true; 276 } 277 278 if (N.getOpcode() != ISD::ADD) { 279 Base = N; 280 if (N.getOpcode() == ISD::FrameIndex) { 281 int FI = cast<FrameIndexSDNode>(N)->getIndex(); 282 Base = CurDAG->getTargetFrameIndex(FI, TLI.getPointerTy()); 283 } 284 Offset = CurDAG->getRegister(0, MVT::i32); 285 Opc = CurDAG->getTargetConstant(ARM_AM::getAM3Opc(ARM_AM::add, 0),MVT::i32); 286 return true; 287 } 288 289 // If the RHS is +/- imm8, fold into addr mode. 290 if (ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(N.getOperand(1))) { 291 int RHSC = (int)RHS->getZExtValue(); 292 if ((RHSC >= 0 && RHSC < 256) || 293 (RHSC < 0 && RHSC > -256)) { // note -256 itself isn't allowed. 294 Base = N.getOperand(0); 295 if (Base.getOpcode() == ISD::FrameIndex) { 296 int FI = cast<FrameIndexSDNode>(Base)->getIndex(); 297 Base = CurDAG->getTargetFrameIndex(FI, TLI.getPointerTy()); 298 } 299 Offset = CurDAG->getRegister(0, MVT::i32); 300 301 ARM_AM::AddrOpc AddSub = ARM_AM::add; 302 if (RHSC < 0) { 303 AddSub = ARM_AM::sub; 304 RHSC = - RHSC; 305 } 306 Opc = CurDAG->getTargetConstant(ARM_AM::getAM3Opc(AddSub, RHSC),MVT::i32); 307 return true; 308 } 309 } 310 311 Base = N.getOperand(0); 312 Offset = N.getOperand(1); 313 Opc = CurDAG->getTargetConstant(ARM_AM::getAM3Opc(ARM_AM::add, 0), MVT::i32); 314 return true; 315} 316 317bool ARMDAGToDAGISel::SelectAddrMode3Offset(SDValue Op, SDValue N, 318 SDValue &Offset, SDValue &Opc) { 319 unsigned Opcode = Op.getOpcode(); 320 ISD::MemIndexedMode AM = (Opcode == ISD::LOAD) 321 ? cast<LoadSDNode>(Op)->getAddressingMode() 322 : cast<StoreSDNode>(Op)->getAddressingMode(); 323 ARM_AM::AddrOpc AddSub = (AM == ISD::PRE_INC || AM == ISD::POST_INC) 324 ? ARM_AM::add : ARM_AM::sub; 325 if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(N)) { 326 int Val = (int)C->getZExtValue(); 327 if (Val >= 0 && Val < 256) { 328 Offset = CurDAG->getRegister(0, MVT::i32); 329 Opc = CurDAG->getTargetConstant(ARM_AM::getAM3Opc(AddSub, Val), MVT::i32); 330 return true; 331 } 332 } 333 334 Offset = N; 335 Opc = CurDAG->getTargetConstant(ARM_AM::getAM3Opc(AddSub, 0), MVT::i32); 336 return true; 337} 338 339 340bool ARMDAGToDAGISel::SelectAddrMode5(SDValue Op, SDValue N, 341 SDValue &Base, SDValue &Offset) { 342 if (N.getOpcode() != ISD::ADD) { 343 Base = N; 344 if (N.getOpcode() == ISD::FrameIndex) { 345 int FI = cast<FrameIndexSDNode>(N)->getIndex(); 346 Base = CurDAG->getTargetFrameIndex(FI, TLI.getPointerTy()); 347 } else if (N.getOpcode() == ARMISD::Wrapper) { 348 Base = N.getOperand(0); 349 } 350 Offset = CurDAG->getTargetConstant(ARM_AM::getAM5Opc(ARM_AM::add, 0), 351 MVT::i32); 352 return true; 353 } 354 355 // If the RHS is +/- imm8, fold into addr mode. 356 if (ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(N.getOperand(1))) { 357 int RHSC = (int)RHS->getZExtValue(); 358 if ((RHSC & 3) == 0) { // The constant is implicitly multiplied by 4. 359 RHSC >>= 2; 360 if ((RHSC >= 0 && RHSC < 256) || 361 (RHSC < 0 && RHSC > -256)) { // note -256 itself isn't allowed. 362 Base = N.getOperand(0); 363 if (Base.getOpcode() == ISD::FrameIndex) { 364 int FI = cast<FrameIndexSDNode>(Base)->getIndex(); 365 Base = CurDAG->getTargetFrameIndex(FI, TLI.getPointerTy()); 366 } 367 368 ARM_AM::AddrOpc AddSub = ARM_AM::add; 369 if (RHSC < 0) { 370 AddSub = ARM_AM::sub; 371 RHSC = - RHSC; 372 } 373 Offset = CurDAG->getTargetConstant(ARM_AM::getAM5Opc(AddSub, RHSC), 374 MVT::i32); 375 return true; 376 } 377 } 378 } 379 380 Base = N; 381 Offset = CurDAG->getTargetConstant(ARM_AM::getAM5Opc(ARM_AM::add, 0), 382 MVT::i32); 383 return true; 384} 385 386bool ARMDAGToDAGISel::SelectAddrModePC(SDValue Op, SDValue N, 387 SDValue &Offset, SDValue &Label) { 388 if (N.getOpcode() == ARMISD::PIC_ADD && N.hasOneUse()) { 389 Offset = N.getOperand(0); 390 SDValue N1 = N.getOperand(1); 391 Label = CurDAG->getTargetConstant(cast<ConstantSDNode>(N1)->getZExtValue(), 392 MVT::i32); 393 return true; 394 } 395 return false; 396} 397 398bool ARMDAGToDAGISel::SelectThumbAddrModeRR(SDValue Op, SDValue N, 399 SDValue &Base, SDValue &Offset){ 400 // FIXME dl should come from the parent load or store, not the address 401 DebugLoc dl = Op.getDebugLoc(); 402 if (N.getOpcode() != ISD::ADD) { 403 Base = N; 404 // We must materialize a zero in a reg! Returning a constant here 405 // wouldn't work without additional code to position the node within 406 // ISel's topological ordering in a place where ISel will process it 407 // normally. Instead, just explicitly issue a tMOVri8 node! 408 Offset = SDValue(CurDAG->getTargetNode(ARM::tMOVi8, dl, MVT::i32, 409 CurDAG->getTargetConstant(0, MVT::i32)), 0); 410 return true; 411 } 412 413 Base = N.getOperand(0); 414 Offset = N.getOperand(1); 415 return true; 416} 417 418bool 419ARMDAGToDAGISel::SelectThumbAddrModeRI5(SDValue Op, SDValue N, 420 unsigned Scale, SDValue &Base, 421 SDValue &OffImm, SDValue &Offset) { 422 if (Scale == 4) { 423 SDValue TmpBase, TmpOffImm; 424 if (SelectThumbAddrModeSP(Op, N, TmpBase, TmpOffImm)) 425 return false; // We want to select tLDRspi / tSTRspi instead. 426 if (N.getOpcode() == ARMISD::Wrapper && 427 N.getOperand(0).getOpcode() == ISD::TargetConstantPool) 428 return false; // We want to select tLDRpci instead. 429 } 430 431 if (N.getOpcode() != ISD::ADD) { 432 Base = (N.getOpcode() == ARMISD::Wrapper) ? N.getOperand(0) : N; 433 Offset = CurDAG->getRegister(0, MVT::i32); 434 OffImm = CurDAG->getTargetConstant(0, MVT::i32); 435 return true; 436 } 437 438 // Thumb does not have [sp, r] address mode. 439 RegisterSDNode *LHSR = dyn_cast<RegisterSDNode>(N.getOperand(0)); 440 RegisterSDNode *RHSR = dyn_cast<RegisterSDNode>(N.getOperand(1)); 441 if ((LHSR && LHSR->getReg() == ARM::SP) || 442 (RHSR && RHSR->getReg() == ARM::SP)) { 443 Base = N; 444 Offset = CurDAG->getRegister(0, MVT::i32); 445 OffImm = CurDAG->getTargetConstant(0, MVT::i32); 446 return true; 447 } 448 449 // If the RHS is + imm5 * scale, fold into addr mode. 450 if (ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(N.getOperand(1))) { 451 int RHSC = (int)RHS->getZExtValue(); 452 if ((RHSC & (Scale-1)) == 0) { // The constant is implicitly multiplied. 453 RHSC /= Scale; 454 if (RHSC >= 0 && RHSC < 32) { 455 Base = N.getOperand(0); 456 Offset = CurDAG->getRegister(0, MVT::i32); 457 OffImm = CurDAG->getTargetConstant(RHSC, MVT::i32); 458 return true; 459 } 460 } 461 } 462 463 Base = N.getOperand(0); 464 Offset = N.getOperand(1); 465 OffImm = CurDAG->getTargetConstant(0, MVT::i32); 466 return true; 467} 468 469bool ARMDAGToDAGISel::SelectThumbAddrModeS1(SDValue Op, SDValue N, 470 SDValue &Base, SDValue &OffImm, 471 SDValue &Offset) { 472 return SelectThumbAddrModeRI5(Op, N, 1, Base, OffImm, Offset); 473} 474 475bool ARMDAGToDAGISel::SelectThumbAddrModeS2(SDValue Op, SDValue N, 476 SDValue &Base, SDValue &OffImm, 477 SDValue &Offset) { 478 return SelectThumbAddrModeRI5(Op, N, 2, Base, OffImm, Offset); 479} 480 481bool ARMDAGToDAGISel::SelectThumbAddrModeS4(SDValue Op, SDValue N, 482 SDValue &Base, SDValue &OffImm, 483 SDValue &Offset) { 484 return SelectThumbAddrModeRI5(Op, N, 4, Base, OffImm, Offset); 485} 486 487bool ARMDAGToDAGISel::SelectThumbAddrModeSP(SDValue Op, SDValue N, 488 SDValue &Base, SDValue &OffImm) { 489 if (N.getOpcode() == ISD::FrameIndex) { 490 int FI = cast<FrameIndexSDNode>(N)->getIndex(); 491 Base = CurDAG->getTargetFrameIndex(FI, TLI.getPointerTy()); 492 OffImm = CurDAG->getTargetConstant(0, MVT::i32); 493 return true; 494 } 495 496 if (N.getOpcode() != ISD::ADD) 497 return false; 498 499 RegisterSDNode *LHSR = dyn_cast<RegisterSDNode>(N.getOperand(0)); 500 if (N.getOperand(0).getOpcode() == ISD::FrameIndex || 501 (LHSR && LHSR->getReg() == ARM::SP)) { 502 // If the RHS is + imm8 * scale, fold into addr mode. 503 if (ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(N.getOperand(1))) { 504 int RHSC = (int)RHS->getZExtValue(); 505 if ((RHSC & 3) == 0) { // The constant is implicitly multiplied. 506 RHSC >>= 2; 507 if (RHSC >= 0 && RHSC < 256) { 508 Base = N.getOperand(0); 509 if (Base.getOpcode() == ISD::FrameIndex) { 510 int FI = cast<FrameIndexSDNode>(Base)->getIndex(); 511 Base = CurDAG->getTargetFrameIndex(FI, TLI.getPointerTy()); 512 } 513 OffImm = CurDAG->getTargetConstant(RHSC, MVT::i32); 514 return true; 515 } 516 } 517 } 518 } 519 520 return false; 521} 522 523bool ARMDAGToDAGISel::SelectShifterOperand(SDValue Op, 524 SDValue N, 525 SDValue &BaseReg, 526 SDValue &Opc) { 527 ARM_AM::ShiftOpc ShOpcVal = ARM_AM::getShiftOpcForNode(N); 528 529 // Don't match base register only case. That is matched to a separate 530 // lower complexity pattern with explicit register operand. 531 if (ShOpcVal == ARM_AM::no_shift) return false; 532 533 BaseReg = N.getOperand(0); 534 unsigned ShImmVal = 0; 535 if (ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(N.getOperand(1))) 536 ShImmVal = RHS->getZExtValue() & 31; 537 else 538 return false; 539 540 Opc = getI32Imm(ARM_AM::getSORegOpc(ShOpcVal, ShImmVal)); 541 542 return true; 543} 544 545bool ARMDAGToDAGISel::SelectShifterOperandReg(SDValue Op, 546 SDValue N, 547 SDValue &BaseReg, 548 SDValue &ShReg, 549 SDValue &Opc) { 550 ARM_AM::ShiftOpc ShOpcVal = ARM_AM::getShiftOpcForNode(N); 551 552 // Don't match base register only case. That is matched to a separate 553 // lower complexity pattern with explicit register operand. 554 if (ShOpcVal == ARM_AM::no_shift) return false; 555 556 BaseReg = N.getOperand(0); 557 unsigned ShImmVal = 0; 558 if (ConstantSDNode *RHS = dyn_cast<ConstantSDNode>(N.getOperand(1))) { 559 ShReg = CurDAG->getRegister(0, MVT::i32); 560 ShImmVal = RHS->getZExtValue() & 31; 561 } else { 562 ShReg = N.getOperand(1); 563 } 564 Opc = CurDAG->getTargetConstant(ARM_AM::getSORegOpc(ShOpcVal, ShImmVal), 565 MVT::i32); 566 return true; 567} 568 569/// getAL - Returns a ARMCC::AL immediate node. 570static inline SDValue getAL(SelectionDAG *CurDAG) { 571 return CurDAG->getTargetConstant((uint64_t)ARMCC::AL, MVT::i32); 572} 573 574 575SDNode *ARMDAGToDAGISel::Select(SDValue Op) { 576 SDNode *N = Op.getNode(); 577 DebugLoc dl = N->getDebugLoc(); 578 579 if (N->isMachineOpcode()) 580 return NULL; // Already selected. 581 582 switch (N->getOpcode()) { 583 default: break; 584 case ISD::Constant: { 585 unsigned Val = cast<ConstantSDNode>(N)->getZExtValue(); 586 bool UseCP = true; 587 if (Subtarget->isThumb()) { 588 if (Subtarget->hasThumb2()) 589 // Thumb2 has the MOVT instruction, so all immediates can 590 // be done with MOV + MOVT, at worst. 591 UseCP = 0; 592 else 593 UseCP = (Val > 255 && // MOV 594 ~Val > 255 && // MOV + MVN 595 !ARM_AM::isThumbImmShiftedVal(Val)); // MOV + LSL 596 } else 597 UseCP = (ARM_AM::getSOImmVal(Val) == -1 && // MOV 598 ARM_AM::getSOImmVal(~Val) == -1 && // MVN 599 !ARM_AM::isSOImmTwoPartVal(Val)); // two instrs. 600 if (UseCP) { 601 SDValue CPIdx = 602 CurDAG->getTargetConstantPool(ConstantInt::get(Type::Int32Ty, Val), 603 TLI.getPointerTy()); 604 605 SDNode *ResNode; 606 if (Subtarget->isThumb()) 607 ResNode = CurDAG->getTargetNode(ARM::tLDRcp, dl, MVT::i32, MVT::Other, 608 CPIdx, CurDAG->getEntryNode()); 609 else { 610 SDValue Ops[] = { 611 CPIdx, 612 CurDAG->getRegister(0, MVT::i32), 613 CurDAG->getTargetConstant(0, MVT::i32), 614 getAL(CurDAG), 615 CurDAG->getRegister(0, MVT::i32), 616 CurDAG->getEntryNode() 617 }; 618 ResNode=CurDAG->getTargetNode(ARM::LDRcp, dl, MVT::i32, MVT::Other, 619 Ops, 6); 620 } 621 ReplaceUses(Op, SDValue(ResNode, 0)); 622 return NULL; 623 } 624 625 // Other cases are autogenerated. 626 break; 627 } 628 case ISD::FrameIndex: { 629 // Selects to ADDri FI, 0 which in turn will become ADDri SP, imm. 630 int FI = cast<FrameIndexSDNode>(N)->getIndex(); 631 SDValue TFI = CurDAG->getTargetFrameIndex(FI, TLI.getPointerTy()); 632 if (Subtarget->isThumb()) { 633 return CurDAG->SelectNodeTo(N, ARM::tADDrSPi, MVT::i32, TFI, 634 CurDAG->getTargetConstant(0, MVT::i32)); 635 } else { 636 SDValue Ops[] = { TFI, CurDAG->getTargetConstant(0, MVT::i32), 637 getAL(CurDAG), CurDAG->getRegister(0, MVT::i32), 638 CurDAG->getRegister(0, MVT::i32) }; 639 return CurDAG->SelectNodeTo(N, ARM::ADDri, MVT::i32, Ops, 5); 640 } 641 } 642 case ISD::ADD: { 643 if (!Subtarget->isThumb()) 644 break; 645 // Select add sp, c to tADDhirr. 646 SDValue N0 = Op.getOperand(0); 647 SDValue N1 = Op.getOperand(1); 648 RegisterSDNode *LHSR = dyn_cast<RegisterSDNode>(Op.getOperand(0)); 649 RegisterSDNode *RHSR = dyn_cast<RegisterSDNode>(Op.getOperand(1)); 650 if (LHSR && LHSR->getReg() == ARM::SP) { 651 std::swap(N0, N1); 652 std::swap(LHSR, RHSR); 653 } 654 if (RHSR && RHSR->getReg() == ARM::SP) { 655 SDValue Val = SDValue(CurDAG->getTargetNode(ARM::tMOVlor2hir, dl, 656 Op.getValueType(), N0, N0), 0); 657 return CurDAG->SelectNodeTo(N, ARM::tADDhirr, Op.getValueType(), Val, N1); 658 } 659 break; 660 } 661 case ISD::MUL: 662 if (Subtarget->isThumb()) 663 break; 664 if (ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op.getOperand(1))) { 665 unsigned RHSV = C->getZExtValue(); 666 if (!RHSV) break; 667 if (isPowerOf2_32(RHSV-1)) { // 2^n+1? 668 SDValue V = Op.getOperand(0); 669 unsigned ShImm = ARM_AM::getSORegOpc(ARM_AM::lsl, Log2_32(RHSV-1)); 670 SDValue Ops[] = { V, V, CurDAG->getRegister(0, MVT::i32), 671 CurDAG->getTargetConstant(ShImm, MVT::i32), 672 getAL(CurDAG), CurDAG->getRegister(0, MVT::i32), 673 CurDAG->getRegister(0, MVT::i32) }; 674 return CurDAG->SelectNodeTo(N, ARM::ADDrs, MVT::i32, Ops, 7); 675 } 676 if (isPowerOf2_32(RHSV+1)) { // 2^n-1? 677 SDValue V = Op.getOperand(0); 678 unsigned ShImm = ARM_AM::getSORegOpc(ARM_AM::lsl, Log2_32(RHSV+1)); 679 SDValue Ops[] = { V, V, CurDAG->getRegister(0, MVT::i32), 680 CurDAG->getTargetConstant(ShImm, MVT::i32), 681 getAL(CurDAG), CurDAG->getRegister(0, MVT::i32), 682 CurDAG->getRegister(0, MVT::i32) }; 683 return CurDAG->SelectNodeTo(N, ARM::RSBrs, MVT::i32, Ops, 7); 684 } 685 } 686 break; 687 case ARMISD::FMRRD: 688 return CurDAG->getTargetNode(ARM::FMRRD, dl, MVT::i32, MVT::i32, 689 Op.getOperand(0), getAL(CurDAG), 690 CurDAG->getRegister(0, MVT::i32)); 691 case ISD::UMUL_LOHI: { 692 SDValue Ops[] = { Op.getOperand(0), Op.getOperand(1), 693 getAL(CurDAG), CurDAG->getRegister(0, MVT::i32), 694 CurDAG->getRegister(0, MVT::i32) }; 695 return CurDAG->getTargetNode(ARM::UMULL, dl, MVT::i32, MVT::i32, Ops, 5); 696 } 697 case ISD::SMUL_LOHI: { 698 SDValue Ops[] = { Op.getOperand(0), Op.getOperand(1), 699 getAL(CurDAG), CurDAG->getRegister(0, MVT::i32), 700 CurDAG->getRegister(0, MVT::i32) }; 701 return CurDAG->getTargetNode(ARM::SMULL, dl, MVT::i32, MVT::i32, Ops, 5); 702 } 703 case ISD::LOAD: { 704 LoadSDNode *LD = cast<LoadSDNode>(Op); 705 ISD::MemIndexedMode AM = LD->getAddressingMode(); 706 MVT LoadedVT = LD->getMemoryVT(); 707 if (AM != ISD::UNINDEXED) { 708 SDValue Offset, AMOpc; 709 bool isPre = (AM == ISD::PRE_INC) || (AM == ISD::PRE_DEC); 710 unsigned Opcode = 0; 711 bool Match = false; 712 if (LoadedVT == MVT::i32 && 713 SelectAddrMode2Offset(Op, LD->getOffset(), Offset, AMOpc)) { 714 Opcode = isPre ? ARM::LDR_PRE : ARM::LDR_POST; 715 Match = true; 716 } else if (LoadedVT == MVT::i16 && 717 SelectAddrMode3Offset(Op, LD->getOffset(), Offset, AMOpc)) { 718 Match = true; 719 Opcode = (LD->getExtensionType() == ISD::SEXTLOAD) 720 ? (isPre ? ARM::LDRSH_PRE : ARM::LDRSH_POST) 721 : (isPre ? ARM::LDRH_PRE : ARM::LDRH_POST); 722 } else if (LoadedVT == MVT::i8 || LoadedVT == MVT::i1) { 723 if (LD->getExtensionType() == ISD::SEXTLOAD) { 724 if (SelectAddrMode3Offset(Op, LD->getOffset(), Offset, AMOpc)) { 725 Match = true; 726 Opcode = isPre ? ARM::LDRSB_PRE : ARM::LDRSB_POST; 727 } 728 } else { 729 if (SelectAddrMode2Offset(Op, LD->getOffset(), Offset, AMOpc)) { 730 Match = true; 731 Opcode = isPre ? ARM::LDRB_PRE : ARM::LDRB_POST; 732 } 733 } 734 } 735 736 if (Match) { 737 SDValue Chain = LD->getChain(); 738 SDValue Base = LD->getBasePtr(); 739 SDValue Ops[]= { Base, Offset, AMOpc, getAL(CurDAG), 740 CurDAG->getRegister(0, MVT::i32), Chain }; 741 return CurDAG->getTargetNode(Opcode, dl, MVT::i32, MVT::i32, 742 MVT::Other, Ops, 6); 743 } 744 } 745 // Other cases are autogenerated. 746 break; 747 } 748 case ARMISD::BRCOND: { 749 // Pattern: (ARMbrcond:void (bb:Other):$dst, (imm:i32):$cc) 750 // Emits: (Bcc:void (bb:Other):$dst, (imm:i32):$cc) 751 // Pattern complexity = 6 cost = 1 size = 0 752 753 // Pattern: (ARMbrcond:void (bb:Other):$dst, (imm:i32):$cc) 754 // Emits: (tBcc:void (bb:Other):$dst, (imm:i32):$cc) 755 // Pattern complexity = 6 cost = 1 size = 0 756 757 unsigned Opc = Subtarget->isThumb() ? ARM::tBcc : ARM::Bcc; 758 SDValue Chain = Op.getOperand(0); 759 SDValue N1 = Op.getOperand(1); 760 SDValue N2 = Op.getOperand(2); 761 SDValue N3 = Op.getOperand(3); 762 SDValue InFlag = Op.getOperand(4); 763 assert(N1.getOpcode() == ISD::BasicBlock); 764 assert(N2.getOpcode() == ISD::Constant); 765 assert(N3.getOpcode() == ISD::Register); 766 767 SDValue Tmp2 = CurDAG->getTargetConstant(((unsigned) 768 cast<ConstantSDNode>(N2)->getZExtValue()), 769 MVT::i32); 770 SDValue Ops[] = { N1, Tmp2, N3, Chain, InFlag }; 771 SDNode *ResNode = CurDAG->getTargetNode(Opc, dl, MVT::Other, 772 MVT::Flag, Ops, 5); 773 Chain = SDValue(ResNode, 0); 774 if (Op.getNode()->getNumValues() == 2) { 775 InFlag = SDValue(ResNode, 1); 776 ReplaceUses(SDValue(Op.getNode(), 1), InFlag); 777 } 778 ReplaceUses(SDValue(Op.getNode(), 0), SDValue(Chain.getNode(), Chain.getResNo())); 779 return NULL; 780 } 781 case ARMISD::CMOV: { 782 bool isThumb = Subtarget->isThumb(); 783 MVT VT = Op.getValueType(); 784 SDValue N0 = Op.getOperand(0); 785 SDValue N1 = Op.getOperand(1); 786 SDValue N2 = Op.getOperand(2); 787 SDValue N3 = Op.getOperand(3); 788 SDValue InFlag = Op.getOperand(4); 789 assert(N2.getOpcode() == ISD::Constant); 790 assert(N3.getOpcode() == ISD::Register); 791 792 // Pattern: (ARMcmov:i32 GPR:i32:$false, so_reg:i32:$true, (imm:i32):$cc) 793 // Emits: (MOVCCs:i32 GPR:i32:$false, so_reg:i32:$true, (imm:i32):$cc) 794 // Pattern complexity = 18 cost = 1 size = 0 795 SDValue CPTmp0; 796 SDValue CPTmp1; 797 SDValue CPTmp2; 798 if (!isThumb && VT == MVT::i32 && 799 SelectShifterOperandReg(Op, N1, CPTmp0, CPTmp1, CPTmp2)) { 800 SDValue Tmp2 = CurDAG->getTargetConstant(((unsigned) 801 cast<ConstantSDNode>(N2)->getZExtValue()), 802 MVT::i32); 803 SDValue Ops[] = { N0, CPTmp0, CPTmp1, CPTmp2, Tmp2, N3, InFlag }; 804 return CurDAG->SelectNodeTo(Op.getNode(), ARM::MOVCCs, MVT::i32, Ops, 7); 805 } 806 807 // Pattern: (ARMcmov:i32 GPR:i32:$false, 808 // (imm:i32)<<P:Predicate_so_imm>><<X:so_imm_XFORM>>:$true, 809 // (imm:i32):$cc) 810 // Emits: (MOVCCi:i32 GPR:i32:$false, 811 // (so_imm_XFORM:i32 (imm:i32):$true), (imm:i32):$cc) 812 // Pattern complexity = 10 cost = 1 size = 0 813 if (VT == MVT::i32 && 814 N3.getOpcode() == ISD::Constant && 815 Predicate_so_imm(N3.getNode())) { 816 SDValue Tmp1 = CurDAG->getTargetConstant(((unsigned) 817 cast<ConstantSDNode>(N1)->getZExtValue()), 818 MVT::i32); 819 Tmp1 = Transform_so_imm_XFORM(Tmp1.getNode()); 820 SDValue Tmp2 = CurDAG->getTargetConstant(((unsigned) 821 cast<ConstantSDNode>(N2)->getZExtValue()), 822 MVT::i32); 823 SDValue Ops[] = { N0, Tmp1, Tmp2, N3, InFlag }; 824 return CurDAG->SelectNodeTo(Op.getNode(), ARM::MOVCCi, MVT::i32, Ops, 5); 825 } 826 827 // Pattern: (ARMcmov:i32 GPR:i32:$false, GPR:i32:$true, (imm:i32):$cc) 828 // Emits: (MOVCCr:i32 GPR:i32:$false, GPR:i32:$true, (imm:i32):$cc) 829 // Pattern complexity = 6 cost = 1 size = 0 830 // 831 // Pattern: (ARMcmov:i32 GPR:i32:$false, GPR:i32:$true, (imm:i32):$cc) 832 // Emits: (tMOVCCr:i32 GPR:i32:$false, GPR:i32:$true, (imm:i32):$cc) 833 // Pattern complexity = 6 cost = 11 size = 0 834 // 835 // Also FCPYScc and FCPYDcc. 836 SDValue Tmp2 = CurDAG->getTargetConstant(((unsigned) 837 cast<ConstantSDNode>(N2)->getZExtValue()), 838 MVT::i32); 839 SDValue Ops[] = { N0, N1, Tmp2, N3, InFlag }; 840 unsigned Opc = 0; 841 switch (VT.getSimpleVT()) { 842 default: assert(false && "Illegal conditional move type!"); 843 break; 844 case MVT::i32: 845 Opc = isThumb ? ARM::tMOVCCr : ARM::MOVCCr; 846 break; 847 case MVT::f32: 848 Opc = ARM::FCPYScc; 849 break; 850 case MVT::f64: 851 Opc = ARM::FCPYDcc; 852 break; 853 } 854 return CurDAG->SelectNodeTo(Op.getNode(), Opc, VT, Ops, 5); 855 } 856 case ARMISD::CNEG: { 857 MVT VT = Op.getValueType(); 858 SDValue N0 = Op.getOperand(0); 859 SDValue N1 = Op.getOperand(1); 860 SDValue N2 = Op.getOperand(2); 861 SDValue N3 = Op.getOperand(3); 862 SDValue InFlag = Op.getOperand(4); 863 assert(N2.getOpcode() == ISD::Constant); 864 assert(N3.getOpcode() == ISD::Register); 865 866 SDValue Tmp2 = CurDAG->getTargetConstant(((unsigned) 867 cast<ConstantSDNode>(N2)->getZExtValue()), 868 MVT::i32); 869 SDValue Ops[] = { N0, N1, Tmp2, N3, InFlag }; 870 unsigned Opc = 0; 871 switch (VT.getSimpleVT()) { 872 default: assert(false && "Illegal conditional move type!"); 873 break; 874 case MVT::f32: 875 Opc = ARM::FNEGScc; 876 break; 877 case MVT::f64: 878 Opc = ARM::FNEGDcc; 879 break; 880 } 881 return CurDAG->SelectNodeTo(Op.getNode(), Opc, VT, Ops, 5); 882 } 883 884 case ISD::DECLARE: { 885 SDValue Chain = Op.getOperand(0); 886 SDValue N1 = Op.getOperand(1); 887 SDValue N2 = Op.getOperand(2); 888 FrameIndexSDNode *FINode = dyn_cast<FrameIndexSDNode>(N1); 889 // FIXME: handle VLAs. 890 if (!FINode) { 891 ReplaceUses(Op.getValue(0), Chain); 892 return NULL; 893 } 894 if (N2.getOpcode() == ARMISD::PIC_ADD && isa<LoadSDNode>(N2.getOperand(0))) 895 N2 = N2.getOperand(0); 896 LoadSDNode *Ld = dyn_cast<LoadSDNode>(N2); 897 if (!Ld) { 898 ReplaceUses(Op.getValue(0), Chain); 899 return NULL; 900 } 901 SDValue BasePtr = Ld->getBasePtr(); 902 assert(BasePtr.getOpcode() == ARMISD::Wrapper && 903 isa<ConstantPoolSDNode>(BasePtr.getOperand(0)) && 904 "llvm.dbg.variable should be a constantpool node"); 905 ConstantPoolSDNode *CP = cast<ConstantPoolSDNode>(BasePtr.getOperand(0)); 906 GlobalValue *GV = 0; 907 if (CP->isMachineConstantPoolEntry()) { 908 ARMConstantPoolValue *ACPV = (ARMConstantPoolValue*)CP->getMachineCPVal(); 909 GV = ACPV->getGV(); 910 } else 911 GV = dyn_cast<GlobalValue>(CP->getConstVal()); 912 if (!GV) { 913 ReplaceUses(Op.getValue(0), Chain); 914 return NULL; 915 } 916 917 SDValue Tmp1 = CurDAG->getTargetFrameIndex(FINode->getIndex(), 918 TLI.getPointerTy()); 919 SDValue Tmp2 = CurDAG->getTargetGlobalAddress(GV, TLI.getPointerTy()); 920 SDValue Ops[] = { Tmp1, Tmp2, Chain }; 921 return CurDAG->getTargetNode(TargetInstrInfo::DECLARE, dl, 922 MVT::Other, Ops, 3); 923 } 924 925 case ISD::CONCAT_VECTORS: { 926 MVT VT = Op.getValueType(); 927 assert(VT.is128BitVector() && Op.getNumOperands() == 2 && 928 "unexpected CONCAT_VECTORS"); 929 SDValue N0 = Op.getOperand(0); 930 SDValue N1 = Op.getOperand(1); 931 SDNode *Result = 932 CurDAG->getTargetNode(TargetInstrInfo::IMPLICIT_DEF, dl, VT); 933 if (N0.getOpcode() != ISD::UNDEF) 934 Result = CurDAG->getTargetNode(TargetInstrInfo::INSERT_SUBREG, dl, VT, 935 SDValue(Result, 0), N0, 936 CurDAG->getTargetConstant(arm_dsubreg_0, 937 MVT::i32)); 938 if (N1.getOpcode() != ISD::UNDEF) 939 Result = CurDAG->getTargetNode(TargetInstrInfo::INSERT_SUBREG, dl, VT, 940 SDValue(Result, 0), N1, 941 CurDAG->getTargetConstant(arm_dsubreg_1, 942 MVT::i32)); 943 return Result; 944 } 945 946 case ISD::VECTOR_SHUFFLE: { 947 MVT VT = Op.getValueType(); 948 949 // Match 128-bit splat to VDUPLANEQ. (This could be done with a Pat in 950 // ARMInstrNEON.td but it is awkward because the shuffle mask needs to be 951 // transformed first into a lane number and then to both a subregister 952 // index and an adjusted lane number.) If the source operand is a 953 // SCALAR_TO_VECTOR, leave it so it will be matched later as a VDUP. 954 ShuffleVectorSDNode *SVOp = cast<ShuffleVectorSDNode>(N); 955 if (VT.is128BitVector() && SVOp->isSplat() && 956 Op.getOperand(0).getOpcode() != ISD::SCALAR_TO_VECTOR && 957 Op.getOperand(1).getOpcode() == ISD::UNDEF) { 958 unsigned LaneVal = SVOp->getSplatIndex(); 959 960 MVT HalfVT; 961 unsigned Opc = 0; 962 switch (VT.getVectorElementType().getSimpleVT()) { 963 default: assert(false && "unhandled VDUP splat type"); 964 case MVT::i8: Opc = ARM::VDUPLN8q; HalfVT = MVT::v8i8; break; 965 case MVT::i16: Opc = ARM::VDUPLN16q; HalfVT = MVT::v4i16; break; 966 case MVT::i32: Opc = ARM::VDUPLN32q; HalfVT = MVT::v2i32; break; 967 case MVT::f32: Opc = ARM::VDUPLNfq; HalfVT = MVT::v2f32; break; 968 } 969 970 // The source operand needs to be changed to a subreg of the original 971 // 128-bit operand, and the lane number needs to be adjusted accordingly. 972 unsigned NumElts = VT.getVectorNumElements() / 2; 973 unsigned SRVal = (LaneVal < NumElts ? arm_dsubreg_0 : arm_dsubreg_1); 974 SDValue SR = CurDAG->getTargetConstant(SRVal, MVT::i32); 975 SDValue NewLane = CurDAG->getTargetConstant(LaneVal % NumElts, MVT::i32); 976 SDNode *SubReg = CurDAG->getTargetNode(TargetInstrInfo::EXTRACT_SUBREG, 977 dl, HalfVT, N->getOperand(0), SR); 978 return CurDAG->SelectNodeTo(N, Opc, VT, SDValue(SubReg, 0), NewLane); 979 } 980 981 break; 982 } 983 } 984 985 return SelectCode(Op); 986} 987 988bool ARMDAGToDAGISel:: 989SelectInlineAsmMemoryOperand(const SDValue &Op, char ConstraintCode, 990 std::vector<SDValue> &OutOps) { 991 assert(ConstraintCode == 'm' && "unexpected asm memory constraint"); 992 993 SDValue Base, Offset, Opc; 994 if (!SelectAddrMode2(Op, Op, Base, Offset, Opc)) 995 return true; 996 997 OutOps.push_back(Base); 998 OutOps.push_back(Offset); 999 OutOps.push_back(Opc); 1000 return false; 1001} 1002 1003/// createARMISelDag - This pass converts a legalized DAG into a 1004/// ARM-specific DAG, ready for instruction scheduling. 1005/// 1006FunctionPass *llvm::createARMISelDag(ARMTargetMachine &TM) { 1007 return new ARMDAGToDAGISel(TM); 1008} 1009