llvm-6502/lib/Target/AArch64/AArch64ISelLowering.cpp
Craig Topper f67c7d7e8c Make some arrays 'static const'
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@186311 91177308-0d34-0410-b5e6-96231b3b80d8
2013-07-15 07:22:00 +00:00

2983 lines
112 KiB
C++

//===-- AArch64ISelLowering.cpp - AArch64 DAG Lowering Implementation -----===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines the interfaces that AArch64 uses to lower LLVM code into a
// selection DAG.
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "aarch64-isel"
#include "AArch64.h"
#include "AArch64ISelLowering.h"
#include "AArch64MachineFunctionInfo.h"
#include "AArch64TargetMachine.h"
#include "AArch64TargetObjectFile.h"
#include "Utils/AArch64BaseInfo.h"
#include "llvm/CodeGen/Analysis.h"
#include "llvm/CodeGen/CallingConvLower.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/TargetLoweringObjectFileImpl.h"
#include "llvm/IR/CallingConv.h"
using namespace llvm;
static TargetLoweringObjectFile *createTLOF(AArch64TargetMachine &TM) {
const AArch64Subtarget *Subtarget = &TM.getSubtarget<AArch64Subtarget>();
if (Subtarget->isTargetLinux())
return new AArch64LinuxTargetObjectFile();
if (Subtarget->isTargetELF())
return new TargetLoweringObjectFileELF();
llvm_unreachable("unknown subtarget type");
}
AArch64TargetLowering::AArch64TargetLowering(AArch64TargetMachine &TM)
: TargetLowering(TM, createTLOF(TM)), Itins(TM.getInstrItineraryData()) {
// SIMD compares set the entire lane's bits to 1
setBooleanVectorContents(ZeroOrNegativeOneBooleanContent);
// Scalar register <-> type mapping
addRegisterClass(MVT::i32, &AArch64::GPR32RegClass);
addRegisterClass(MVT::i64, &AArch64::GPR64RegClass);
addRegisterClass(MVT::f16, &AArch64::FPR16RegClass);
addRegisterClass(MVT::f32, &AArch64::FPR32RegClass);
addRegisterClass(MVT::f64, &AArch64::FPR64RegClass);
addRegisterClass(MVT::f128, &AArch64::FPR128RegClass);
computeRegisterProperties();
// We combine OR nodes for bitfield and NEON BSL operations.
setTargetDAGCombine(ISD::OR);
setTargetDAGCombine(ISD::AND);
setTargetDAGCombine(ISD::SRA);
// AArch64 does not have i1 loads, or much of anything for i1 really.
setLoadExtAction(ISD::SEXTLOAD, MVT::i1, Promote);
setLoadExtAction(ISD::ZEXTLOAD, MVT::i1, Promote);
setLoadExtAction(ISD::EXTLOAD, MVT::i1, Promote);
setStackPointerRegisterToSaveRestore(AArch64::XSP);
setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i64, Expand);
setOperationAction(ISD::STACKRESTORE, MVT::Other, Expand);
setOperationAction(ISD::STACKSAVE, MVT::Other, Expand);
// We'll lower globals to wrappers for selection.
setOperationAction(ISD::GlobalAddress, MVT::i64, Custom);
setOperationAction(ISD::GlobalTLSAddress, MVT::i64, Custom);
// A64 instructions have the comparison predicate attached to the user of the
// result, but having a separate comparison is valuable for matching.
setOperationAction(ISD::BR_CC, MVT::i32, Custom);
setOperationAction(ISD::BR_CC, MVT::i64, Custom);
setOperationAction(ISD::BR_CC, MVT::f32, Custom);
setOperationAction(ISD::BR_CC, MVT::f64, Custom);
setOperationAction(ISD::SELECT, MVT::i32, Custom);
setOperationAction(ISD::SELECT, MVT::i64, Custom);
setOperationAction(ISD::SELECT, MVT::f32, Custom);
setOperationAction(ISD::SELECT, MVT::f64, Custom);
setOperationAction(ISD::SELECT_CC, MVT::i32, Custom);
setOperationAction(ISD::SELECT_CC, MVT::i64, Custom);
setOperationAction(ISD::SELECT_CC, MVT::f32, Custom);
setOperationAction(ISD::SELECT_CC, MVT::f64, Custom);
setOperationAction(ISD::BRCOND, MVT::Other, Custom);
setOperationAction(ISD::SETCC, MVT::i32, Custom);
setOperationAction(ISD::SETCC, MVT::i64, Custom);
setOperationAction(ISD::SETCC, MVT::f32, Custom);
setOperationAction(ISD::SETCC, MVT::f64, Custom);
setOperationAction(ISD::BR_JT, MVT::Other, Expand);
setOperationAction(ISD::JumpTable, MVT::i32, Custom);
setOperationAction(ISD::JumpTable, MVT::i64, Custom);
setOperationAction(ISD::VASTART, MVT::Other, Custom);
setOperationAction(ISD::VACOPY, MVT::Other, Custom);
setOperationAction(ISD::VAEND, MVT::Other, Expand);
setOperationAction(ISD::VAARG, MVT::Other, Expand);
setOperationAction(ISD::BlockAddress, MVT::i64, Custom);
setOperationAction(ISD::ROTL, MVT::i32, Expand);
setOperationAction(ISD::ROTL, MVT::i64, Expand);
setOperationAction(ISD::UREM, MVT::i32, Expand);
setOperationAction(ISD::UREM, MVT::i64, Expand);
setOperationAction(ISD::UDIVREM, MVT::i32, Expand);
setOperationAction(ISD::UDIVREM, MVT::i64, Expand);
setOperationAction(ISD::SREM, MVT::i32, Expand);
setOperationAction(ISD::SREM, MVT::i64, Expand);
setOperationAction(ISD::SDIVREM, MVT::i32, Expand);
setOperationAction(ISD::SDIVREM, MVT::i64, Expand);
setOperationAction(ISD::CTPOP, MVT::i32, Expand);
setOperationAction(ISD::CTPOP, MVT::i64, Expand);
// Legal floating-point operations.
setOperationAction(ISD::FABS, MVT::f32, Legal);
setOperationAction(ISD::FABS, MVT::f64, Legal);
setOperationAction(ISD::FCEIL, MVT::f32, Legal);
setOperationAction(ISD::FCEIL, MVT::f64, Legal);
setOperationAction(ISD::FFLOOR, MVT::f32, Legal);
setOperationAction(ISD::FFLOOR, MVT::f64, Legal);
setOperationAction(ISD::FNEARBYINT, MVT::f32, Legal);
setOperationAction(ISD::FNEARBYINT, MVT::f64, Legal);
setOperationAction(ISD::FNEG, MVT::f32, Legal);
setOperationAction(ISD::FNEG, MVT::f64, Legal);
setOperationAction(ISD::FRINT, MVT::f32, Legal);
setOperationAction(ISD::FRINT, MVT::f64, Legal);
setOperationAction(ISD::FSQRT, MVT::f32, Legal);
setOperationAction(ISD::FSQRT, MVT::f64, Legal);
setOperationAction(ISD::FTRUNC, MVT::f32, Legal);
setOperationAction(ISD::FTRUNC, MVT::f64, Legal);
setOperationAction(ISD::ConstantFP, MVT::f32, Legal);
setOperationAction(ISD::ConstantFP, MVT::f64, Legal);
setOperationAction(ISD::ConstantFP, MVT::f128, Legal);
// Illegal floating-point operations.
setOperationAction(ISD::FCOPYSIGN, MVT::f32, Expand);
setOperationAction(ISD::FCOPYSIGN, MVT::f64, Expand);
setOperationAction(ISD::FCOS, MVT::f32, Expand);
setOperationAction(ISD::FCOS, MVT::f64, Expand);
setOperationAction(ISD::FEXP, MVT::f32, Expand);
setOperationAction(ISD::FEXP, MVT::f64, Expand);
setOperationAction(ISD::FEXP2, MVT::f32, Expand);
setOperationAction(ISD::FEXP2, MVT::f64, Expand);
setOperationAction(ISD::FLOG, MVT::f32, Expand);
setOperationAction(ISD::FLOG, MVT::f64, Expand);
setOperationAction(ISD::FLOG2, MVT::f32, Expand);
setOperationAction(ISD::FLOG2, MVT::f64, Expand);
setOperationAction(ISD::FLOG10, MVT::f32, Expand);
setOperationAction(ISD::FLOG10, MVT::f64, Expand);
setOperationAction(ISD::FPOW, MVT::f32, Expand);
setOperationAction(ISD::FPOW, MVT::f64, Expand);
setOperationAction(ISD::FPOWI, MVT::f32, Expand);
setOperationAction(ISD::FPOWI, MVT::f64, Expand);
setOperationAction(ISD::FREM, MVT::f32, Expand);
setOperationAction(ISD::FREM, MVT::f64, Expand);
setOperationAction(ISD::FSIN, MVT::f32, Expand);
setOperationAction(ISD::FSIN, MVT::f64, Expand);
setOperationAction(ISD::FSINCOS, MVT::f32, Expand);
setOperationAction(ISD::FSINCOS, MVT::f64, Expand);
// Virtually no operation on f128 is legal, but LLVM can't expand them when
// there's a valid register class, so we need custom operations in most cases.
setOperationAction(ISD::FABS, MVT::f128, Expand);
setOperationAction(ISD::FADD, MVT::f128, Custom);
setOperationAction(ISD::FCOPYSIGN, MVT::f128, Expand);
setOperationAction(ISD::FCOS, MVT::f128, Expand);
setOperationAction(ISD::FDIV, MVT::f128, Custom);
setOperationAction(ISD::FMA, MVT::f128, Expand);
setOperationAction(ISD::FMUL, MVT::f128, Custom);
setOperationAction(ISD::FNEG, MVT::f128, Expand);
setOperationAction(ISD::FP_EXTEND, MVT::f128, Expand);
setOperationAction(ISD::FP_ROUND, MVT::f128, Expand);
setOperationAction(ISD::FPOW, MVT::f128, Expand);
setOperationAction(ISD::FREM, MVT::f128, Expand);
setOperationAction(ISD::FRINT, MVT::f128, Expand);
setOperationAction(ISD::FSIN, MVT::f128, Expand);
setOperationAction(ISD::FSINCOS, MVT::f128, Expand);
setOperationAction(ISD::FSQRT, MVT::f128, Expand);
setOperationAction(ISD::FSUB, MVT::f128, Custom);
setOperationAction(ISD::FTRUNC, MVT::f128, Expand);
setOperationAction(ISD::SETCC, MVT::f128, Custom);
setOperationAction(ISD::BR_CC, MVT::f128, Custom);
setOperationAction(ISD::SELECT, MVT::f128, Expand);
setOperationAction(ISD::SELECT_CC, MVT::f128, Custom);
setOperationAction(ISD::FP_EXTEND, MVT::f128, Custom);
// Lowering for many of the conversions is actually specified by the non-f128
// type. The LowerXXX function will be trivial when f128 isn't involved.
setOperationAction(ISD::FP_TO_SINT, MVT::i32, Custom);
setOperationAction(ISD::FP_TO_SINT, MVT::i64, Custom);
setOperationAction(ISD::FP_TO_SINT, MVT::i128, Custom);
setOperationAction(ISD::FP_TO_UINT, MVT::i32, Custom);
setOperationAction(ISD::FP_TO_UINT, MVT::i64, Custom);
setOperationAction(ISD::FP_TO_UINT, MVT::i128, Custom);
setOperationAction(ISD::SINT_TO_FP, MVT::i32, Custom);
setOperationAction(ISD::SINT_TO_FP, MVT::i64, Custom);
setOperationAction(ISD::SINT_TO_FP, MVT::i128, Custom);
setOperationAction(ISD::UINT_TO_FP, MVT::i32, Custom);
setOperationAction(ISD::UINT_TO_FP, MVT::i64, Custom);
setOperationAction(ISD::UINT_TO_FP, MVT::i128, Custom);
setOperationAction(ISD::FP_ROUND, MVT::f32, Custom);
setOperationAction(ISD::FP_ROUND, MVT::f64, Custom);
// This prevents LLVM trying to compress double constants into a floating
// constant-pool entry and trying to load from there. It's of doubtful benefit
// for A64: we'd need LDR followed by FCVT, I believe.
setLoadExtAction(ISD::EXTLOAD, MVT::f64, Expand);
setLoadExtAction(ISD::EXTLOAD, MVT::f32, Expand);
setLoadExtAction(ISD::EXTLOAD, MVT::f16, Expand);
setTruncStoreAction(MVT::f128, MVT::f64, Expand);
setTruncStoreAction(MVT::f128, MVT::f32, Expand);
setTruncStoreAction(MVT::f128, MVT::f16, Expand);
setTruncStoreAction(MVT::f64, MVT::f32, Expand);
setTruncStoreAction(MVT::f64, MVT::f16, Expand);
setTruncStoreAction(MVT::f32, MVT::f16, Expand);
setExceptionPointerRegister(AArch64::X0);
setExceptionSelectorRegister(AArch64::X1);
}
EVT AArch64TargetLowering::getSetCCResultType(LLVMContext &, EVT VT) const {
// It's reasonably important that this value matches the "natural" legal
// promotion from i1 for scalar types. Otherwise LegalizeTypes can get itself
// in a twist (e.g. inserting an any_extend which then becomes i64 -> i64).
if (!VT.isVector()) return MVT::i32;
return VT.changeVectorElementTypeToInteger();
}
static void getExclusiveOperation(unsigned Size, AtomicOrdering Ord,
unsigned &LdrOpc,
unsigned &StrOpc) {
static const unsigned LoadBares[] = {AArch64::LDXR_byte, AArch64::LDXR_hword,
AArch64::LDXR_word, AArch64::LDXR_dword};
static const unsigned LoadAcqs[] = {AArch64::LDAXR_byte, AArch64::LDAXR_hword,
AArch64::LDAXR_word, AArch64::LDAXR_dword};
static const unsigned StoreBares[] = {AArch64::STXR_byte, AArch64::STXR_hword,
AArch64::STXR_word, AArch64::STXR_dword};
static const unsigned StoreRels[] = {AArch64::STLXR_byte,AArch64::STLXR_hword,
AArch64::STLXR_word, AArch64::STLXR_dword};
const unsigned *LoadOps, *StoreOps;
if (Ord == Acquire || Ord == AcquireRelease || Ord == SequentiallyConsistent)
LoadOps = LoadAcqs;
else
LoadOps = LoadBares;
if (Ord == Release || Ord == AcquireRelease || Ord == SequentiallyConsistent)
StoreOps = StoreRels;
else
StoreOps = StoreBares;
assert(isPowerOf2_32(Size) && Size <= 8 &&
"unsupported size for atomic binary op!");
LdrOpc = LoadOps[Log2_32(Size)];
StrOpc = StoreOps[Log2_32(Size)];
}
MachineBasicBlock *
AArch64TargetLowering::emitAtomicBinary(MachineInstr *MI, MachineBasicBlock *BB,
unsigned Size,
unsigned BinOpcode) const {
// This also handles ATOMIC_SWAP, indicated by BinOpcode==0.
const TargetInstrInfo *TII = getTargetMachine().getInstrInfo();
const BasicBlock *LLVM_BB = BB->getBasicBlock();
MachineFunction *MF = BB->getParent();
MachineFunction::iterator It = BB;
++It;
unsigned dest = MI->getOperand(0).getReg();
unsigned ptr = MI->getOperand(1).getReg();
unsigned incr = MI->getOperand(2).getReg();
AtomicOrdering Ord = static_cast<AtomicOrdering>(MI->getOperand(3).getImm());
DebugLoc dl = MI->getDebugLoc();
MachineRegisterInfo &MRI = BB->getParent()->getRegInfo();
unsigned ldrOpc, strOpc;
getExclusiveOperation(Size, Ord, ldrOpc, strOpc);
MachineBasicBlock *loopMBB = MF->CreateMachineBasicBlock(LLVM_BB);
MachineBasicBlock *exitMBB = MF->CreateMachineBasicBlock(LLVM_BB);
MF->insert(It, loopMBB);
MF->insert(It, exitMBB);
// Transfer the remainder of BB and its successor edges to exitMBB.
exitMBB->splice(exitMBB->begin(), BB,
llvm::next(MachineBasicBlock::iterator(MI)),
BB->end());
exitMBB->transferSuccessorsAndUpdatePHIs(BB);
const TargetRegisterClass *TRC
= Size == 8 ? &AArch64::GPR64RegClass : &AArch64::GPR32RegClass;
unsigned scratch = (!BinOpcode) ? incr : MRI.createVirtualRegister(TRC);
// thisMBB:
// ...
// fallthrough --> loopMBB
BB->addSuccessor(loopMBB);
// loopMBB:
// ldxr dest, ptr
// <binop> scratch, dest, incr
// stxr stxr_status, scratch, ptr
// cbnz stxr_status, loopMBB
// fallthrough --> exitMBB
BB = loopMBB;
BuildMI(BB, dl, TII->get(ldrOpc), dest).addReg(ptr);
if (BinOpcode) {
// All arithmetic operations we'll be creating are designed to take an extra
// shift or extend operand, which we can conveniently set to zero.
// Operand order needs to go the other way for NAND.
if (BinOpcode == AArch64::BICwww_lsl || BinOpcode == AArch64::BICxxx_lsl)
BuildMI(BB, dl, TII->get(BinOpcode), scratch)
.addReg(incr).addReg(dest).addImm(0);
else
BuildMI(BB, dl, TII->get(BinOpcode), scratch)
.addReg(dest).addReg(incr).addImm(0);
}
// From the stxr, the register is GPR32; from the cmp it's GPR32wsp
unsigned stxr_status = MRI.createVirtualRegister(&AArch64::GPR32RegClass);
MRI.constrainRegClass(stxr_status, &AArch64::GPR32wspRegClass);
BuildMI(BB, dl, TII->get(strOpc), stxr_status).addReg(scratch).addReg(ptr);
BuildMI(BB, dl, TII->get(AArch64::CBNZw))
.addReg(stxr_status).addMBB(loopMBB);
BB->addSuccessor(loopMBB);
BB->addSuccessor(exitMBB);
// exitMBB:
// ...
BB = exitMBB;
MI->eraseFromParent(); // The instruction is gone now.
return BB;
}
MachineBasicBlock *
AArch64TargetLowering::emitAtomicBinaryMinMax(MachineInstr *MI,
MachineBasicBlock *BB,
unsigned Size,
unsigned CmpOp,
A64CC::CondCodes Cond) const {
const TargetInstrInfo *TII = getTargetMachine().getInstrInfo();
const BasicBlock *LLVM_BB = BB->getBasicBlock();
MachineFunction *MF = BB->getParent();
MachineFunction::iterator It = BB;
++It;
unsigned dest = MI->getOperand(0).getReg();
unsigned ptr = MI->getOperand(1).getReg();
unsigned incr = MI->getOperand(2).getReg();
AtomicOrdering Ord = static_cast<AtomicOrdering>(MI->getOperand(3).getImm());
unsigned oldval = dest;
DebugLoc dl = MI->getDebugLoc();
MachineRegisterInfo &MRI = BB->getParent()->getRegInfo();
const TargetRegisterClass *TRC, *TRCsp;
if (Size == 8) {
TRC = &AArch64::GPR64RegClass;
TRCsp = &AArch64::GPR64xspRegClass;
} else {
TRC = &AArch64::GPR32RegClass;
TRCsp = &AArch64::GPR32wspRegClass;
}
unsigned ldrOpc, strOpc;
getExclusiveOperation(Size, Ord, ldrOpc, strOpc);
MachineBasicBlock *loopMBB = MF->CreateMachineBasicBlock(LLVM_BB);
MachineBasicBlock *exitMBB = MF->CreateMachineBasicBlock(LLVM_BB);
MF->insert(It, loopMBB);
MF->insert(It, exitMBB);
// Transfer the remainder of BB and its successor edges to exitMBB.
exitMBB->splice(exitMBB->begin(), BB,
llvm::next(MachineBasicBlock::iterator(MI)),
BB->end());
exitMBB->transferSuccessorsAndUpdatePHIs(BB);
unsigned scratch = MRI.createVirtualRegister(TRC);
MRI.constrainRegClass(scratch, TRCsp);
// thisMBB:
// ...
// fallthrough --> loopMBB
BB->addSuccessor(loopMBB);
// loopMBB:
// ldxr dest, ptr
// cmp incr, dest (, sign extend if necessary)
// csel scratch, dest, incr, cond
// stxr stxr_status, scratch, ptr
// cbnz stxr_status, loopMBB
// fallthrough --> exitMBB
BB = loopMBB;
BuildMI(BB, dl, TII->get(ldrOpc), dest).addReg(ptr);
// Build compare and cmov instructions.
MRI.constrainRegClass(incr, TRCsp);
BuildMI(BB, dl, TII->get(CmpOp))
.addReg(incr).addReg(oldval).addImm(0);
BuildMI(BB, dl, TII->get(Size == 8 ? AArch64::CSELxxxc : AArch64::CSELwwwc),
scratch)
.addReg(oldval).addReg(incr).addImm(Cond);
unsigned stxr_status = MRI.createVirtualRegister(&AArch64::GPR32RegClass);
MRI.constrainRegClass(stxr_status, &AArch64::GPR32wspRegClass);
BuildMI(BB, dl, TII->get(strOpc), stxr_status)
.addReg(scratch).addReg(ptr);
BuildMI(BB, dl, TII->get(AArch64::CBNZw))
.addReg(stxr_status).addMBB(loopMBB);
BB->addSuccessor(loopMBB);
BB->addSuccessor(exitMBB);
// exitMBB:
// ...
BB = exitMBB;
MI->eraseFromParent(); // The instruction is gone now.
return BB;
}
MachineBasicBlock *
AArch64TargetLowering::emitAtomicCmpSwap(MachineInstr *MI,
MachineBasicBlock *BB,
unsigned Size) const {
unsigned dest = MI->getOperand(0).getReg();
unsigned ptr = MI->getOperand(1).getReg();
unsigned oldval = MI->getOperand(2).getReg();
unsigned newval = MI->getOperand(3).getReg();
AtomicOrdering Ord = static_cast<AtomicOrdering>(MI->getOperand(4).getImm());
const TargetInstrInfo *TII = getTargetMachine().getInstrInfo();
DebugLoc dl = MI->getDebugLoc();
MachineRegisterInfo &MRI = BB->getParent()->getRegInfo();
const TargetRegisterClass *TRCsp;
TRCsp = Size == 8 ? &AArch64::GPR64xspRegClass : &AArch64::GPR32wspRegClass;
unsigned ldrOpc, strOpc;
getExclusiveOperation(Size, Ord, ldrOpc, strOpc);
MachineFunction *MF = BB->getParent();
const BasicBlock *LLVM_BB = BB->getBasicBlock();
MachineFunction::iterator It = BB;
++It; // insert the new blocks after the current block
MachineBasicBlock *loop1MBB = MF->CreateMachineBasicBlock(LLVM_BB);
MachineBasicBlock *loop2MBB = MF->CreateMachineBasicBlock(LLVM_BB);
MachineBasicBlock *exitMBB = MF->CreateMachineBasicBlock(LLVM_BB);
MF->insert(It, loop1MBB);
MF->insert(It, loop2MBB);
MF->insert(It, exitMBB);
// Transfer the remainder of BB and its successor edges to exitMBB.
exitMBB->splice(exitMBB->begin(), BB,
llvm::next(MachineBasicBlock::iterator(MI)),
BB->end());
exitMBB->transferSuccessorsAndUpdatePHIs(BB);
// thisMBB:
// ...
// fallthrough --> loop1MBB
BB->addSuccessor(loop1MBB);
// loop1MBB:
// ldxr dest, [ptr]
// cmp dest, oldval
// b.ne exitMBB
BB = loop1MBB;
BuildMI(BB, dl, TII->get(ldrOpc), dest).addReg(ptr);
unsigned CmpOp = Size == 8 ? AArch64::CMPxx_lsl : AArch64::CMPww_lsl;
MRI.constrainRegClass(dest, TRCsp);
BuildMI(BB, dl, TII->get(CmpOp))
.addReg(dest).addReg(oldval).addImm(0);
BuildMI(BB, dl, TII->get(AArch64::Bcc))
.addImm(A64CC::NE).addMBB(exitMBB);
BB->addSuccessor(loop2MBB);
BB->addSuccessor(exitMBB);
// loop2MBB:
// strex stxr_status, newval, [ptr]
// cbnz stxr_status, loop1MBB
BB = loop2MBB;
unsigned stxr_status = MRI.createVirtualRegister(&AArch64::GPR32RegClass);
MRI.constrainRegClass(stxr_status, &AArch64::GPR32wspRegClass);
BuildMI(BB, dl, TII->get(strOpc), stxr_status).addReg(newval).addReg(ptr);
BuildMI(BB, dl, TII->get(AArch64::CBNZw))
.addReg(stxr_status).addMBB(loop1MBB);
BB->addSuccessor(loop1MBB);
BB->addSuccessor(exitMBB);
// exitMBB:
// ...
BB = exitMBB;
MI->eraseFromParent(); // The instruction is gone now.
return BB;
}
MachineBasicBlock *
AArch64TargetLowering::EmitF128CSEL(MachineInstr *MI,
MachineBasicBlock *MBB) const {
// We materialise the F128CSEL pseudo-instruction using conditional branches
// and loads, giving an instruciton sequence like:
// str q0, [sp]
// b.ne IfTrue
// b Finish
// IfTrue:
// str q1, [sp]
// Finish:
// ldr q0, [sp]
//
// Using virtual registers would probably not be beneficial since COPY
// instructions are expensive for f128 (there's no actual instruction to
// implement them).
//
// An alternative would be to do an integer-CSEL on some address. E.g.:
// mov x0, sp
// add x1, sp, #16
// str q0, [x0]
// str q1, [x1]
// csel x0, x0, x1, ne
// ldr q0, [x0]
//
// It's unclear which approach is actually optimal.
const TargetInstrInfo *TII = getTargetMachine().getInstrInfo();
MachineFunction *MF = MBB->getParent();
const BasicBlock *LLVM_BB = MBB->getBasicBlock();
DebugLoc DL = MI->getDebugLoc();
MachineFunction::iterator It = MBB;
++It;
unsigned DestReg = MI->getOperand(0).getReg();
unsigned IfTrueReg = MI->getOperand(1).getReg();
unsigned IfFalseReg = MI->getOperand(2).getReg();
unsigned CondCode = MI->getOperand(3).getImm();
bool NZCVKilled = MI->getOperand(4).isKill();
MachineBasicBlock *TrueBB = MF->CreateMachineBasicBlock(LLVM_BB);
MachineBasicBlock *EndBB = MF->CreateMachineBasicBlock(LLVM_BB);
MF->insert(It, TrueBB);
MF->insert(It, EndBB);
// Transfer rest of current basic-block to EndBB
EndBB->splice(EndBB->begin(), MBB,
llvm::next(MachineBasicBlock::iterator(MI)),
MBB->end());
EndBB->transferSuccessorsAndUpdatePHIs(MBB);
// We need somewhere to store the f128 value needed.
int ScratchFI = MF->getFrameInfo()->CreateSpillStackObject(16, 16);
// [... start of incoming MBB ...]
// str qIFFALSE, [sp]
// b.cc IfTrue
// b Done
BuildMI(MBB, DL, TII->get(AArch64::LSFP128_STR))
.addReg(IfFalseReg)
.addFrameIndex(ScratchFI)
.addImm(0);
BuildMI(MBB, DL, TII->get(AArch64::Bcc))
.addImm(CondCode)
.addMBB(TrueBB);
BuildMI(MBB, DL, TII->get(AArch64::Bimm))
.addMBB(EndBB);
MBB->addSuccessor(TrueBB);
MBB->addSuccessor(EndBB);
// IfTrue:
// str qIFTRUE, [sp]
BuildMI(TrueBB, DL, TII->get(AArch64::LSFP128_STR))
.addReg(IfTrueReg)
.addFrameIndex(ScratchFI)
.addImm(0);
// Note: fallthrough. We can rely on LLVM adding a branch if it reorders the
// blocks.
TrueBB->addSuccessor(EndBB);
// Done:
// ldr qDEST, [sp]
// [... rest of incoming MBB ...]
if (!NZCVKilled)
EndBB->addLiveIn(AArch64::NZCV);
MachineInstr *StartOfEnd = EndBB->begin();
BuildMI(*EndBB, StartOfEnd, DL, TII->get(AArch64::LSFP128_LDR), DestReg)
.addFrameIndex(ScratchFI)
.addImm(0);
MI->eraseFromParent();
return EndBB;
}
MachineBasicBlock *
AArch64TargetLowering::EmitInstrWithCustomInserter(MachineInstr *MI,
MachineBasicBlock *MBB) const {
switch (MI->getOpcode()) {
default: llvm_unreachable("Unhandled instruction with custom inserter");
case AArch64::F128CSEL:
return EmitF128CSEL(MI, MBB);
case AArch64::ATOMIC_LOAD_ADD_I8:
return emitAtomicBinary(MI, MBB, 1, AArch64::ADDwww_lsl);
case AArch64::ATOMIC_LOAD_ADD_I16:
return emitAtomicBinary(MI, MBB, 2, AArch64::ADDwww_lsl);
case AArch64::ATOMIC_LOAD_ADD_I32:
return emitAtomicBinary(MI, MBB, 4, AArch64::ADDwww_lsl);
case AArch64::ATOMIC_LOAD_ADD_I64:
return emitAtomicBinary(MI, MBB, 8, AArch64::ADDxxx_lsl);
case AArch64::ATOMIC_LOAD_SUB_I8:
return emitAtomicBinary(MI, MBB, 1, AArch64::SUBwww_lsl);
case AArch64::ATOMIC_LOAD_SUB_I16:
return emitAtomicBinary(MI, MBB, 2, AArch64::SUBwww_lsl);
case AArch64::ATOMIC_LOAD_SUB_I32:
return emitAtomicBinary(MI, MBB, 4, AArch64::SUBwww_lsl);
case AArch64::ATOMIC_LOAD_SUB_I64:
return emitAtomicBinary(MI, MBB, 8, AArch64::SUBxxx_lsl);
case AArch64::ATOMIC_LOAD_AND_I8:
return emitAtomicBinary(MI, MBB, 1, AArch64::ANDwww_lsl);
case AArch64::ATOMIC_LOAD_AND_I16:
return emitAtomicBinary(MI, MBB, 2, AArch64::ANDwww_lsl);
case AArch64::ATOMIC_LOAD_AND_I32:
return emitAtomicBinary(MI, MBB, 4, AArch64::ANDwww_lsl);
case AArch64::ATOMIC_LOAD_AND_I64:
return emitAtomicBinary(MI, MBB, 8, AArch64::ANDxxx_lsl);
case AArch64::ATOMIC_LOAD_OR_I8:
return emitAtomicBinary(MI, MBB, 1, AArch64::ORRwww_lsl);
case AArch64::ATOMIC_LOAD_OR_I16:
return emitAtomicBinary(MI, MBB, 2, AArch64::ORRwww_lsl);
case AArch64::ATOMIC_LOAD_OR_I32:
return emitAtomicBinary(MI, MBB, 4, AArch64::ORRwww_lsl);
case AArch64::ATOMIC_LOAD_OR_I64:
return emitAtomicBinary(MI, MBB, 8, AArch64::ORRxxx_lsl);
case AArch64::ATOMIC_LOAD_XOR_I8:
return emitAtomicBinary(MI, MBB, 1, AArch64::EORwww_lsl);
case AArch64::ATOMIC_LOAD_XOR_I16:
return emitAtomicBinary(MI, MBB, 2, AArch64::EORwww_lsl);
case AArch64::ATOMIC_LOAD_XOR_I32:
return emitAtomicBinary(MI, MBB, 4, AArch64::EORwww_lsl);
case AArch64::ATOMIC_LOAD_XOR_I64:
return emitAtomicBinary(MI, MBB, 8, AArch64::EORxxx_lsl);
case AArch64::ATOMIC_LOAD_NAND_I8:
return emitAtomicBinary(MI, MBB, 1, AArch64::BICwww_lsl);
case AArch64::ATOMIC_LOAD_NAND_I16:
return emitAtomicBinary(MI, MBB, 2, AArch64::BICwww_lsl);
case AArch64::ATOMIC_LOAD_NAND_I32:
return emitAtomicBinary(MI, MBB, 4, AArch64::BICwww_lsl);
case AArch64::ATOMIC_LOAD_NAND_I64:
return emitAtomicBinary(MI, MBB, 8, AArch64::BICxxx_lsl);
case AArch64::ATOMIC_LOAD_MIN_I8:
return emitAtomicBinaryMinMax(MI, MBB, 1, AArch64::CMPww_sxtb, A64CC::GT);
case AArch64::ATOMIC_LOAD_MIN_I16:
return emitAtomicBinaryMinMax(MI, MBB, 2, AArch64::CMPww_sxth, A64CC::GT);
case AArch64::ATOMIC_LOAD_MIN_I32:
return emitAtomicBinaryMinMax(MI, MBB, 4, AArch64::CMPww_lsl, A64CC::GT);
case AArch64::ATOMIC_LOAD_MIN_I64:
return emitAtomicBinaryMinMax(MI, MBB, 8, AArch64::CMPxx_lsl, A64CC::GT);
case AArch64::ATOMIC_LOAD_MAX_I8:
return emitAtomicBinaryMinMax(MI, MBB, 1, AArch64::CMPww_sxtb, A64CC::LT);
case AArch64::ATOMIC_LOAD_MAX_I16:
return emitAtomicBinaryMinMax(MI, MBB, 2, AArch64::CMPww_sxth, A64CC::LT);
case AArch64::ATOMIC_LOAD_MAX_I32:
return emitAtomicBinaryMinMax(MI, MBB, 4, AArch64::CMPww_lsl, A64CC::LT);
case AArch64::ATOMIC_LOAD_MAX_I64:
return emitAtomicBinaryMinMax(MI, MBB, 8, AArch64::CMPxx_lsl, A64CC::LT);
case AArch64::ATOMIC_LOAD_UMIN_I8:
return emitAtomicBinaryMinMax(MI, MBB, 1, AArch64::CMPww_uxtb, A64CC::HI);
case AArch64::ATOMIC_LOAD_UMIN_I16:
return emitAtomicBinaryMinMax(MI, MBB, 2, AArch64::CMPww_uxth, A64CC::HI);
case AArch64::ATOMIC_LOAD_UMIN_I32:
return emitAtomicBinaryMinMax(MI, MBB, 4, AArch64::CMPww_lsl, A64CC::HI);
case AArch64::ATOMIC_LOAD_UMIN_I64:
return emitAtomicBinaryMinMax(MI, MBB, 8, AArch64::CMPxx_lsl, A64CC::HI);
case AArch64::ATOMIC_LOAD_UMAX_I8:
return emitAtomicBinaryMinMax(MI, MBB, 1, AArch64::CMPww_uxtb, A64CC::LO);
case AArch64::ATOMIC_LOAD_UMAX_I16:
return emitAtomicBinaryMinMax(MI, MBB, 2, AArch64::CMPww_uxth, A64CC::LO);
case AArch64::ATOMIC_LOAD_UMAX_I32:
return emitAtomicBinaryMinMax(MI, MBB, 4, AArch64::CMPww_lsl, A64CC::LO);
case AArch64::ATOMIC_LOAD_UMAX_I64:
return emitAtomicBinaryMinMax(MI, MBB, 8, AArch64::CMPxx_lsl, A64CC::LO);
case AArch64::ATOMIC_SWAP_I8:
return emitAtomicBinary(MI, MBB, 1, 0);
case AArch64::ATOMIC_SWAP_I16:
return emitAtomicBinary(MI, MBB, 2, 0);
case AArch64::ATOMIC_SWAP_I32:
return emitAtomicBinary(MI, MBB, 4, 0);
case AArch64::ATOMIC_SWAP_I64:
return emitAtomicBinary(MI, MBB, 8, 0);
case AArch64::ATOMIC_CMP_SWAP_I8:
return emitAtomicCmpSwap(MI, MBB, 1);
case AArch64::ATOMIC_CMP_SWAP_I16:
return emitAtomicCmpSwap(MI, MBB, 2);
case AArch64::ATOMIC_CMP_SWAP_I32:
return emitAtomicCmpSwap(MI, MBB, 4);
case AArch64::ATOMIC_CMP_SWAP_I64:
return emitAtomicCmpSwap(MI, MBB, 8);
}
}
const char *AArch64TargetLowering::getTargetNodeName(unsigned Opcode) const {
switch (Opcode) {
case AArch64ISD::BR_CC: return "AArch64ISD::BR_CC";
case AArch64ISD::Call: return "AArch64ISD::Call";
case AArch64ISD::FPMOV: return "AArch64ISD::FPMOV";
case AArch64ISD::GOTLoad: return "AArch64ISD::GOTLoad";
case AArch64ISD::BFI: return "AArch64ISD::BFI";
case AArch64ISD::EXTR: return "AArch64ISD::EXTR";
case AArch64ISD::Ret: return "AArch64ISD::Ret";
case AArch64ISD::SBFX: return "AArch64ISD::SBFX";
case AArch64ISD::SELECT_CC: return "AArch64ISD::SELECT_CC";
case AArch64ISD::SETCC: return "AArch64ISD::SETCC";
case AArch64ISD::TC_RETURN: return "AArch64ISD::TC_RETURN";
case AArch64ISD::THREAD_POINTER: return "AArch64ISD::THREAD_POINTER";
case AArch64ISD::TLSDESCCALL: return "AArch64ISD::TLSDESCCALL";
case AArch64ISD::WrapperLarge: return "AArch64ISD::WrapperLarge";
case AArch64ISD::WrapperSmall: return "AArch64ISD::WrapperSmall";
default: return NULL;
}
}
static const uint16_t AArch64FPRArgRegs[] = {
AArch64::Q0, AArch64::Q1, AArch64::Q2, AArch64::Q3,
AArch64::Q4, AArch64::Q5, AArch64::Q6, AArch64::Q7
};
static const unsigned NumFPRArgRegs = llvm::array_lengthof(AArch64FPRArgRegs);
static const uint16_t AArch64ArgRegs[] = {
AArch64::X0, AArch64::X1, AArch64::X2, AArch64::X3,
AArch64::X4, AArch64::X5, AArch64::X6, AArch64::X7
};
static const unsigned NumArgRegs = llvm::array_lengthof(AArch64ArgRegs);
static bool CC_AArch64NoMoreRegs(unsigned ValNo, MVT ValVT, MVT LocVT,
CCValAssign::LocInfo LocInfo,
ISD::ArgFlagsTy ArgFlags, CCState &State) {
// Mark all remaining general purpose registers as allocated. We don't
// backtrack: if (for example) an i128 gets put on the stack, no subsequent
// i64 will go in registers (C.11).
for (unsigned i = 0; i < NumArgRegs; ++i)
State.AllocateReg(AArch64ArgRegs[i]);
return false;
}
#include "AArch64GenCallingConv.inc"
CCAssignFn *AArch64TargetLowering::CCAssignFnForNode(CallingConv::ID CC) const {
switch(CC) {
default: llvm_unreachable("Unsupported calling convention");
case CallingConv::Fast:
case CallingConv::C:
return CC_A64_APCS;
}
}
void
AArch64TargetLowering::SaveVarArgRegisters(CCState &CCInfo, SelectionDAG &DAG,
SDLoc DL, SDValue &Chain) const {
MachineFunction &MF = DAG.getMachineFunction();
MachineFrameInfo *MFI = MF.getFrameInfo();
AArch64MachineFunctionInfo *FuncInfo
= MF.getInfo<AArch64MachineFunctionInfo>();
SmallVector<SDValue, 8> MemOps;
unsigned FirstVariadicGPR = CCInfo.getFirstUnallocated(AArch64ArgRegs,
NumArgRegs);
unsigned FirstVariadicFPR = CCInfo.getFirstUnallocated(AArch64FPRArgRegs,
NumFPRArgRegs);
unsigned GPRSaveSize = 8 * (NumArgRegs - FirstVariadicGPR);
int GPRIdx = 0;
if (GPRSaveSize != 0) {
GPRIdx = MFI->CreateStackObject(GPRSaveSize, 8, false);
SDValue FIN = DAG.getFrameIndex(GPRIdx, getPointerTy());
for (unsigned i = FirstVariadicGPR; i < NumArgRegs; ++i) {
unsigned VReg = MF.addLiveIn(AArch64ArgRegs[i], &AArch64::GPR64RegClass);
SDValue Val = DAG.getCopyFromReg(Chain, DL, VReg, MVT::i64);
SDValue Store = DAG.getStore(Val.getValue(1), DL, Val, FIN,
MachinePointerInfo::getStack(i * 8),
false, false, 0);
MemOps.push_back(Store);
FIN = DAG.getNode(ISD::ADD, DL, getPointerTy(), FIN,
DAG.getConstant(8, getPointerTy()));
}
}
unsigned FPRSaveSize = 16 * (NumFPRArgRegs - FirstVariadicFPR);
int FPRIdx = 0;
if (FPRSaveSize != 0) {
FPRIdx = MFI->CreateStackObject(FPRSaveSize, 16, false);
SDValue FIN = DAG.getFrameIndex(FPRIdx, getPointerTy());
for (unsigned i = FirstVariadicFPR; i < NumFPRArgRegs; ++i) {
unsigned VReg = MF.addLiveIn(AArch64FPRArgRegs[i],
&AArch64::FPR128RegClass);
SDValue Val = DAG.getCopyFromReg(Chain, DL, VReg, MVT::f128);
SDValue Store = DAG.getStore(Val.getValue(1), DL, Val, FIN,
MachinePointerInfo::getStack(i * 16),
false, false, 0);
MemOps.push_back(Store);
FIN = DAG.getNode(ISD::ADD, DL, getPointerTy(), FIN,
DAG.getConstant(16, getPointerTy()));
}
}
int StackIdx = MFI->CreateFixedObject(8, CCInfo.getNextStackOffset(), true);
FuncInfo->setVariadicStackIdx(StackIdx);
FuncInfo->setVariadicGPRIdx(GPRIdx);
FuncInfo->setVariadicGPRSize(GPRSaveSize);
FuncInfo->setVariadicFPRIdx(FPRIdx);
FuncInfo->setVariadicFPRSize(FPRSaveSize);
if (!MemOps.empty()) {
Chain = DAG.getNode(ISD::TokenFactor, DL, MVT::Other, &MemOps[0],
MemOps.size());
}
}
SDValue
AArch64TargetLowering::LowerFormalArguments(SDValue Chain,
CallingConv::ID CallConv, bool isVarArg,
const SmallVectorImpl<ISD::InputArg> &Ins,
SDLoc dl, SelectionDAG &DAG,
SmallVectorImpl<SDValue> &InVals) const {
MachineFunction &MF = DAG.getMachineFunction();
AArch64MachineFunctionInfo *FuncInfo
= MF.getInfo<AArch64MachineFunctionInfo>();
MachineFrameInfo *MFI = MF.getFrameInfo();
bool TailCallOpt = MF.getTarget().Options.GuaranteedTailCallOpt;
SmallVector<CCValAssign, 16> ArgLocs;
CCState CCInfo(CallConv, isVarArg, DAG.getMachineFunction(),
getTargetMachine(), ArgLocs, *DAG.getContext());
CCInfo.AnalyzeFormalArguments(Ins, CCAssignFnForNode(CallConv));
SmallVector<SDValue, 16> ArgValues;
SDValue ArgValue;
for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
CCValAssign &VA = ArgLocs[i];
ISD::ArgFlagsTy Flags = Ins[i].Flags;
if (Flags.isByVal()) {
// Byval is used for small structs and HFAs in the PCS, but the system
// should work in a non-compliant manner for larger structs.
EVT PtrTy = getPointerTy();
int Size = Flags.getByValSize();
unsigned NumRegs = (Size + 7) / 8;
unsigned FrameIdx = MFI->CreateFixedObject(8 * NumRegs,
VA.getLocMemOffset(),
false);
SDValue FrameIdxN = DAG.getFrameIndex(FrameIdx, PtrTy);
InVals.push_back(FrameIdxN);
continue;
} else if (VA.isRegLoc()) {
MVT RegVT = VA.getLocVT();
const TargetRegisterClass *RC = getRegClassFor(RegVT);
unsigned Reg = MF.addLiveIn(VA.getLocReg(), RC);
ArgValue = DAG.getCopyFromReg(Chain, dl, Reg, RegVT);
} else { // VA.isRegLoc()
assert(VA.isMemLoc());
int FI = MFI->CreateFixedObject(VA.getLocVT().getSizeInBits()/8,
VA.getLocMemOffset(), true);
SDValue FIN = DAG.getFrameIndex(FI, getPointerTy());
ArgValue = DAG.getLoad(VA.getLocVT(), dl, Chain, FIN,
MachinePointerInfo::getFixedStack(FI),
false, false, false, 0);
}
switch (VA.getLocInfo()) {
default: llvm_unreachable("Unknown loc info!");
case CCValAssign::Full: break;
case CCValAssign::BCvt:
ArgValue = DAG.getNode(ISD::BITCAST,dl, VA.getValVT(), ArgValue);
break;
case CCValAssign::SExt:
case CCValAssign::ZExt:
case CCValAssign::AExt: {
unsigned DestSize = VA.getValVT().getSizeInBits();
unsigned DestSubReg;
switch (DestSize) {
case 8: DestSubReg = AArch64::sub_8; break;
case 16: DestSubReg = AArch64::sub_16; break;
case 32: DestSubReg = AArch64::sub_32; break;
case 64: DestSubReg = AArch64::sub_64; break;
default: llvm_unreachable("Unexpected argument promotion");
}
ArgValue = SDValue(DAG.getMachineNode(TargetOpcode::EXTRACT_SUBREG, dl,
VA.getValVT(), ArgValue,
DAG.getTargetConstant(DestSubReg, MVT::i32)),
0);
break;
}
}
InVals.push_back(ArgValue);
}
if (isVarArg)
SaveVarArgRegisters(CCInfo, DAG, dl, Chain);
unsigned StackArgSize = CCInfo.getNextStackOffset();
if (DoesCalleeRestoreStack(CallConv, TailCallOpt)) {
// This is a non-standard ABI so by fiat I say we're allowed to make full
// use of the stack area to be popped, which must be aligned to 16 bytes in
// any case:
StackArgSize = RoundUpToAlignment(StackArgSize, 16);
// If we're expected to restore the stack (e.g. fastcc) then we'll be adding
// a multiple of 16.
FuncInfo->setArgumentStackToRestore(StackArgSize);
// This realignment carries over to the available bytes below. Our own
// callers will guarantee the space is free by giving an aligned value to
// CALLSEQ_START.
}
// Even if we're not expected to free up the space, it's useful to know how
// much is there while considering tail calls (because we can reuse it).
FuncInfo->setBytesInStackArgArea(StackArgSize);
return Chain;
}
SDValue
AArch64TargetLowering::LowerReturn(SDValue Chain,
CallingConv::ID CallConv, bool isVarArg,
const SmallVectorImpl<ISD::OutputArg> &Outs,
const SmallVectorImpl<SDValue> &OutVals,
SDLoc dl, SelectionDAG &DAG) const {
// CCValAssign - represent the assignment of the return value to a location.
SmallVector<CCValAssign, 16> RVLocs;
// CCState - Info about the registers and stack slots.
CCState CCInfo(CallConv, isVarArg, DAG.getMachineFunction(),
getTargetMachine(), RVLocs, *DAG.getContext());
// Analyze outgoing return values.
CCInfo.AnalyzeReturn(Outs, CCAssignFnForNode(CallConv));
SDValue Flag;
SmallVector<SDValue, 4> RetOps(1, Chain);
for (unsigned i = 0, e = RVLocs.size(); i != e; ++i) {
// PCS: "If the type, T, of the result of a function is such that
// void func(T arg) would require that arg be passed as a value in a
// register (or set of registers) according to the rules in 5.4, then the
// result is returned in the same registers as would be used for such an
// argument.
//
// Otherwise, the caller shall reserve a block of memory of sufficient
// size and alignment to hold the result. The address of the memory block
// shall be passed as an additional argument to the function in x8."
//
// This is implemented in two places. The register-return values are dealt
// with here, more complex returns are passed as an sret parameter, which
// means we don't have to worry about it during actual return.
CCValAssign &VA = RVLocs[i];
assert(VA.isRegLoc() && "Only register-returns should be created by PCS");
SDValue Arg = OutVals[i];
// There's no convenient note in the ABI about this as there is for normal
// arguments, but it says return values are passed in the same registers as
// an argument would be. I believe that includes the comments about
// unspecified higher bits, putting the burden of widening on the *caller*
// for return values.
switch (VA.getLocInfo()) {
default: llvm_unreachable("Unknown loc info");
case CCValAssign::Full: break;
case CCValAssign::SExt:
case CCValAssign::ZExt:
case CCValAssign::AExt:
// Floating-point values should only be extended when they're going into
// memory, which can't happen here so an integer extend is acceptable.
Arg = DAG.getNode(ISD::ANY_EXTEND, dl, VA.getLocVT(), Arg);
break;
case CCValAssign::BCvt:
Arg = DAG.getNode(ISD::BITCAST, dl, VA.getLocVT(), Arg);
break;
}
Chain = DAG.getCopyToReg(Chain, dl, VA.getLocReg(), Arg, Flag);
Flag = Chain.getValue(1);
RetOps.push_back(DAG.getRegister(VA.getLocReg(), VA.getLocVT()));
}
RetOps[0] = Chain; // Update chain.
// Add the flag if we have it.
if (Flag.getNode())
RetOps.push_back(Flag);
return DAG.getNode(AArch64ISD::Ret, dl, MVT::Other,
&RetOps[0], RetOps.size());
}
SDValue
AArch64TargetLowering::LowerCall(CallLoweringInfo &CLI,
SmallVectorImpl<SDValue> &InVals) const {
SelectionDAG &DAG = CLI.DAG;
SDLoc &dl = CLI.DL;
SmallVectorImpl<ISD::OutputArg> &Outs = CLI.Outs;
SmallVectorImpl<SDValue> &OutVals = CLI.OutVals;
SmallVectorImpl<ISD::InputArg> &Ins = CLI.Ins;
SDValue Chain = CLI.Chain;
SDValue Callee = CLI.Callee;
bool &IsTailCall = CLI.IsTailCall;
CallingConv::ID CallConv = CLI.CallConv;
bool IsVarArg = CLI.IsVarArg;
MachineFunction &MF = DAG.getMachineFunction();
AArch64MachineFunctionInfo *FuncInfo
= MF.getInfo<AArch64MachineFunctionInfo>();
bool TailCallOpt = MF.getTarget().Options.GuaranteedTailCallOpt;
bool IsStructRet = !Outs.empty() && Outs[0].Flags.isSRet();
bool IsSibCall = false;
if (IsTailCall) {
IsTailCall = IsEligibleForTailCallOptimization(Callee, CallConv,
IsVarArg, IsStructRet, MF.getFunction()->hasStructRetAttr(),
Outs, OutVals, Ins, DAG);
// A sibling call is one where we're under the usual C ABI and not planning
// to change that but can still do a tail call:
if (!TailCallOpt && IsTailCall)
IsSibCall = true;
}
SmallVector<CCValAssign, 16> ArgLocs;
CCState CCInfo(CallConv, IsVarArg, DAG.getMachineFunction(),
getTargetMachine(), ArgLocs, *DAG.getContext());
CCInfo.AnalyzeCallOperands(Outs, CCAssignFnForNode(CallConv));
// On AArch64 (and all other architectures I'm aware of) the most this has to
// do is adjust the stack pointer.
unsigned NumBytes = RoundUpToAlignment(CCInfo.getNextStackOffset(), 16);
if (IsSibCall) {
// Since we're not changing the ABI to make this a tail call, the memory
// operands are already available in the caller's incoming argument space.
NumBytes = 0;
}
// FPDiff is the byte offset of the call's argument area from the callee's.
// Stores to callee stack arguments will be placed in FixedStackSlots offset
// by this amount for a tail call. In a sibling call it must be 0 because the
// caller will deallocate the entire stack and the callee still expects its
// arguments to begin at SP+0. Completely unused for non-tail calls.
int FPDiff = 0;
if (IsTailCall && !IsSibCall) {
unsigned NumReusableBytes = FuncInfo->getBytesInStackArgArea();
// FPDiff will be negative if this tail call requires more space than we
// would automatically have in our incoming argument space. Positive if we
// can actually shrink the stack.
FPDiff = NumReusableBytes - NumBytes;
// The stack pointer must be 16-byte aligned at all times it's used for a
// memory operation, which in practice means at *all* times and in
// particular across call boundaries. Therefore our own arguments started at
// a 16-byte aligned SP and the delta applied for the tail call should
// satisfy the same constraint.
assert(FPDiff % 16 == 0 && "unaligned stack on tail call");
}
if (!IsSibCall)
Chain = DAG.getCALLSEQ_START(Chain, DAG.getIntPtrConstant(NumBytes, true),
dl);
SDValue StackPtr = DAG.getCopyFromReg(Chain, dl, AArch64::XSP,
getPointerTy());
SmallVector<SDValue, 8> MemOpChains;
SmallVector<std::pair<unsigned, SDValue>, 8> RegsToPass;
for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
CCValAssign &VA = ArgLocs[i];
ISD::ArgFlagsTy Flags = Outs[i].Flags;
SDValue Arg = OutVals[i];
// Callee does the actual widening, so all extensions just use an implicit
// definition of the rest of the Loc. Aesthetically, this would be nicer as
// an ANY_EXTEND, but that isn't valid for floating-point types and this
// alternative works on integer types too.
switch (VA.getLocInfo()) {
default: llvm_unreachable("Unknown loc info!");
case CCValAssign::Full: break;
case CCValAssign::SExt:
case CCValAssign::ZExt:
case CCValAssign::AExt: {
unsigned SrcSize = VA.getValVT().getSizeInBits();
unsigned SrcSubReg;
switch (SrcSize) {
case 8: SrcSubReg = AArch64::sub_8; break;
case 16: SrcSubReg = AArch64::sub_16; break;
case 32: SrcSubReg = AArch64::sub_32; break;
case 64: SrcSubReg = AArch64::sub_64; break;
default: llvm_unreachable("Unexpected argument promotion");
}
Arg = SDValue(DAG.getMachineNode(TargetOpcode::INSERT_SUBREG, dl,
VA.getLocVT(),
DAG.getUNDEF(VA.getLocVT()),
Arg,
DAG.getTargetConstant(SrcSubReg, MVT::i32)),
0);
break;
}
case CCValAssign::BCvt:
Arg = DAG.getNode(ISD::BITCAST, dl, VA.getLocVT(), Arg);
break;
}
if (VA.isRegLoc()) {
// A normal register (sub-) argument. For now we just note it down because
// we want to copy things into registers as late as possible to avoid
// register-pressure (and possibly worse).
RegsToPass.push_back(std::make_pair(VA.getLocReg(), Arg));
continue;
}
assert(VA.isMemLoc() && "unexpected argument location");
SDValue DstAddr;
MachinePointerInfo DstInfo;
if (IsTailCall) {
uint32_t OpSize = Flags.isByVal() ? Flags.getByValSize() :
VA.getLocVT().getSizeInBits();
OpSize = (OpSize + 7) / 8;
int32_t Offset = VA.getLocMemOffset() + FPDiff;
int FI = MF.getFrameInfo()->CreateFixedObject(OpSize, Offset, true);
DstAddr = DAG.getFrameIndex(FI, getPointerTy());
DstInfo = MachinePointerInfo::getFixedStack(FI);
// Make sure any stack arguments overlapping with where we're storing are
// loaded before this eventual operation. Otherwise they'll be clobbered.
Chain = addTokenForArgument(Chain, DAG, MF.getFrameInfo(), FI);
} else {
SDValue PtrOff = DAG.getIntPtrConstant(VA.getLocMemOffset());
DstAddr = DAG.getNode(ISD::ADD, dl, getPointerTy(), StackPtr, PtrOff);
DstInfo = MachinePointerInfo::getStack(VA.getLocMemOffset());
}
if (Flags.isByVal()) {
SDValue SizeNode = DAG.getConstant(Flags.getByValSize(), MVT::i64);
SDValue Cpy = DAG.getMemcpy(Chain, dl, DstAddr, Arg, SizeNode,
Flags.getByValAlign(),
/*isVolatile = */ false,
/*alwaysInline = */ false,
DstInfo, MachinePointerInfo(0));
MemOpChains.push_back(Cpy);
} else {
// Normal stack argument, put it where it's needed.
SDValue Store = DAG.getStore(Chain, dl, Arg, DstAddr, DstInfo,
false, false, 0);
MemOpChains.push_back(Store);
}
}
// The loads and stores generated above shouldn't clash with each
// other. Combining them with this TokenFactor notes that fact for the rest of
// the backend.
if (!MemOpChains.empty())
Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other,
&MemOpChains[0], MemOpChains.size());
// Most of the rest of the instructions need to be glued together; we don't
// want assignments to actual registers used by a call to be rearranged by a
// well-meaning scheduler.
SDValue InFlag;
for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i) {
Chain = DAG.getCopyToReg(Chain, dl, RegsToPass[i].first,
RegsToPass[i].second, InFlag);
InFlag = Chain.getValue(1);
}
// The linker is responsible for inserting veneers when necessary to put a
// function call destination in range, so we don't need to bother with a
// wrapper here.
if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee)) {
const GlobalValue *GV = G->getGlobal();
Callee = DAG.getTargetGlobalAddress(GV, dl, getPointerTy());
} else if (ExternalSymbolSDNode *S = dyn_cast<ExternalSymbolSDNode>(Callee)) {
const char *Sym = S->getSymbol();
Callee = DAG.getTargetExternalSymbol(Sym, getPointerTy());
}
// We don't usually want to end the call-sequence here because we would tidy
// the frame up *after* the call, however in the ABI-changing tail-call case
// we've carefully laid out the parameters so that when sp is reset they'll be
// in the correct location.
if (IsTailCall && !IsSibCall) {
Chain = DAG.getCALLSEQ_END(Chain, DAG.getIntPtrConstant(NumBytes, true),
DAG.getIntPtrConstant(0, true), InFlag, dl);
InFlag = Chain.getValue(1);
}
// We produce the following DAG scheme for the actual call instruction:
// (AArch64Call Chain, Callee, reg1, ..., regn, preserveMask, inflag?
//
// Most arguments aren't going to be used and just keep the values live as
// far as LLVM is concerned. It's expected to be selected as simply "bl
// callee" (for a direct, non-tail call).
std::vector<SDValue> Ops;
Ops.push_back(Chain);
Ops.push_back(Callee);
if (IsTailCall) {
// Each tail call may have to adjust the stack by a different amount, so
// this information must travel along with the operation for eventual
// consumption by emitEpilogue.
Ops.push_back(DAG.getTargetConstant(FPDiff, MVT::i32));
}
for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i)
Ops.push_back(DAG.getRegister(RegsToPass[i].first,
RegsToPass[i].second.getValueType()));
// Add a register mask operand representing the call-preserved registers. This
// is used later in codegen to constrain register-allocation.
const TargetRegisterInfo *TRI = getTargetMachine().getRegisterInfo();
const uint32_t *Mask = TRI->getCallPreservedMask(CallConv);
assert(Mask && "Missing call preserved mask for calling convention");
Ops.push_back(DAG.getRegisterMask(Mask));
// If we needed glue, put it in as the last argument.
if (InFlag.getNode())
Ops.push_back(InFlag);
SDVTList NodeTys = DAG.getVTList(MVT::Other, MVT::Glue);
if (IsTailCall) {
return DAG.getNode(AArch64ISD::TC_RETURN, dl, NodeTys, &Ops[0], Ops.size());
}
Chain = DAG.getNode(AArch64ISD::Call, dl, NodeTys, &Ops[0], Ops.size());
InFlag = Chain.getValue(1);
// Now we can reclaim the stack, just as well do it before working out where
// our return value is.
if (!IsSibCall) {
uint64_t CalleePopBytes
= DoesCalleeRestoreStack(CallConv, TailCallOpt) ? NumBytes : 0;
Chain = DAG.getCALLSEQ_END(Chain, DAG.getIntPtrConstant(NumBytes, true),
DAG.getIntPtrConstant(CalleePopBytes, true),
InFlag, dl);
InFlag = Chain.getValue(1);
}
return LowerCallResult(Chain, InFlag, CallConv,
IsVarArg, Ins, dl, DAG, InVals);
}
SDValue
AArch64TargetLowering::LowerCallResult(SDValue Chain, SDValue InFlag,
CallingConv::ID CallConv, bool IsVarArg,
const SmallVectorImpl<ISD::InputArg> &Ins,
SDLoc dl, SelectionDAG &DAG,
SmallVectorImpl<SDValue> &InVals) const {
// Assign locations to each value returned by this call.
SmallVector<CCValAssign, 16> RVLocs;
CCState CCInfo(CallConv, IsVarArg, DAG.getMachineFunction(),
getTargetMachine(), RVLocs, *DAG.getContext());
CCInfo.AnalyzeCallResult(Ins, CCAssignFnForNode(CallConv));
for (unsigned i = 0; i != RVLocs.size(); ++i) {
CCValAssign VA = RVLocs[i];
// Return values that are too big to fit into registers should use an sret
// pointer, so this can be a lot simpler than the main argument code.
assert(VA.isRegLoc() && "Memory locations not expected for call return");
SDValue Val = DAG.getCopyFromReg(Chain, dl, VA.getLocReg(), VA.getLocVT(),
InFlag);
Chain = Val.getValue(1);
InFlag = Val.getValue(2);
switch (VA.getLocInfo()) {
default: llvm_unreachable("Unknown loc info!");
case CCValAssign::Full: break;
case CCValAssign::BCvt:
Val = DAG.getNode(ISD::BITCAST, dl, VA.getValVT(), Val);
break;
case CCValAssign::ZExt:
case CCValAssign::SExt:
case CCValAssign::AExt:
// Floating-point arguments only get extended/truncated if they're going
// in memory, so using the integer operation is acceptable here.
Val = DAG.getNode(ISD::TRUNCATE, dl, VA.getValVT(), Val);
break;
}
InVals.push_back(Val);
}
return Chain;
}
bool
AArch64TargetLowering::IsEligibleForTailCallOptimization(SDValue Callee,
CallingConv::ID CalleeCC,
bool IsVarArg,
bool IsCalleeStructRet,
bool IsCallerStructRet,
const SmallVectorImpl<ISD::OutputArg> &Outs,
const SmallVectorImpl<SDValue> &OutVals,
const SmallVectorImpl<ISD::InputArg> &Ins,
SelectionDAG& DAG) const {
// For CallingConv::C this function knows whether the ABI needs
// changing. That's not true for other conventions so they will have to opt in
// manually.
if (!IsTailCallConvention(CalleeCC) && CalleeCC != CallingConv::C)
return false;
const MachineFunction &MF = DAG.getMachineFunction();
const Function *CallerF = MF.getFunction();
CallingConv::ID CallerCC = CallerF->getCallingConv();
bool CCMatch = CallerCC == CalleeCC;
// Byval parameters hand the function a pointer directly into the stack area
// we want to reuse during a tail call. Working around this *is* possible (see
// X86) but less efficient and uglier in LowerCall.
for (Function::const_arg_iterator i = CallerF->arg_begin(),
e = CallerF->arg_end(); i != e; ++i)
if (i->hasByValAttr())
return false;
if (getTargetMachine().Options.GuaranteedTailCallOpt) {
if (IsTailCallConvention(CalleeCC) && CCMatch)
return true;
return false;
}
// Now we search for cases where we can use a tail call without changing the
// ABI. Sibcall is used in some places (particularly gcc) to refer to this
// concept.
// I want anyone implementing a new calling convention to think long and hard
// about this assert.
assert((!IsVarArg || CalleeCC == CallingConv::C)
&& "Unexpected variadic calling convention");
if (IsVarArg && !Outs.empty()) {
// At least two cases here: if caller is fastcc then we can't have any
// memory arguments (we'd be expected to clean up the stack afterwards). If
// caller is C then we could potentially use its argument area.
// FIXME: for now we take the most conservative of these in both cases:
// disallow all variadic memory operands.
SmallVector<CCValAssign, 16> ArgLocs;
CCState CCInfo(CalleeCC, IsVarArg, DAG.getMachineFunction(),
getTargetMachine(), ArgLocs, *DAG.getContext());
CCInfo.AnalyzeCallOperands(Outs, CCAssignFnForNode(CalleeCC));
for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i)
if (!ArgLocs[i].isRegLoc())
return false;
}
// If the calling conventions do not match, then we'd better make sure the
// results are returned in the same way as what the caller expects.
if (!CCMatch) {
SmallVector<CCValAssign, 16> RVLocs1;
CCState CCInfo1(CalleeCC, false, DAG.getMachineFunction(),
getTargetMachine(), RVLocs1, *DAG.getContext());
CCInfo1.AnalyzeCallResult(Ins, CCAssignFnForNode(CalleeCC));
SmallVector<CCValAssign, 16> RVLocs2;
CCState CCInfo2(CallerCC, false, DAG.getMachineFunction(),
getTargetMachine(), RVLocs2, *DAG.getContext());
CCInfo2.AnalyzeCallResult(Ins, CCAssignFnForNode(CallerCC));
if (RVLocs1.size() != RVLocs2.size())
return false;
for (unsigned i = 0, e = RVLocs1.size(); i != e; ++i) {
if (RVLocs1[i].isRegLoc() != RVLocs2[i].isRegLoc())
return false;
if (RVLocs1[i].getLocInfo() != RVLocs2[i].getLocInfo())
return false;
if (RVLocs1[i].isRegLoc()) {
if (RVLocs1[i].getLocReg() != RVLocs2[i].getLocReg())
return false;
} else {
if (RVLocs1[i].getLocMemOffset() != RVLocs2[i].getLocMemOffset())
return false;
}
}
}
// Nothing more to check if the callee is taking no arguments
if (Outs.empty())
return true;
SmallVector<CCValAssign, 16> ArgLocs;
CCState CCInfo(CalleeCC, IsVarArg, DAG.getMachineFunction(),
getTargetMachine(), ArgLocs, *DAG.getContext());
CCInfo.AnalyzeCallOperands(Outs, CCAssignFnForNode(CalleeCC));
const AArch64MachineFunctionInfo *FuncInfo
= MF.getInfo<AArch64MachineFunctionInfo>();
// If the stack arguments for this call would fit into our own save area then
// the call can be made tail.
return CCInfo.getNextStackOffset() <= FuncInfo->getBytesInStackArgArea();
}
bool AArch64TargetLowering::DoesCalleeRestoreStack(CallingConv::ID CallCC,
bool TailCallOpt) const {
return CallCC == CallingConv::Fast && TailCallOpt;
}
bool AArch64TargetLowering::IsTailCallConvention(CallingConv::ID CallCC) const {
return CallCC == CallingConv::Fast;
}
SDValue AArch64TargetLowering::addTokenForArgument(SDValue Chain,
SelectionDAG &DAG,
MachineFrameInfo *MFI,
int ClobberedFI) const {
SmallVector<SDValue, 8> ArgChains;
int64_t FirstByte = MFI->getObjectOffset(ClobberedFI);
int64_t LastByte = FirstByte + MFI->getObjectSize(ClobberedFI) - 1;
// Include the original chain at the beginning of the list. When this is
// used by target LowerCall hooks, this helps legalize find the
// CALLSEQ_BEGIN node.
ArgChains.push_back(Chain);
// Add a chain value for each stack argument corresponding
for (SDNode::use_iterator U = DAG.getEntryNode().getNode()->use_begin(),
UE = DAG.getEntryNode().getNode()->use_end(); U != UE; ++U)
if (LoadSDNode *L = dyn_cast<LoadSDNode>(*U))
if (FrameIndexSDNode *FI = dyn_cast<FrameIndexSDNode>(L->getBasePtr()))
if (FI->getIndex() < 0) {
int64_t InFirstByte = MFI->getObjectOffset(FI->getIndex());
int64_t InLastByte = InFirstByte;
InLastByte += MFI->getObjectSize(FI->getIndex()) - 1;
if ((InFirstByte <= FirstByte && FirstByte <= InLastByte) ||
(FirstByte <= InFirstByte && InFirstByte <= LastByte))
ArgChains.push_back(SDValue(L, 1));
}
// Build a tokenfactor for all the chains.
return DAG.getNode(ISD::TokenFactor, SDLoc(Chain), MVT::Other,
&ArgChains[0], ArgChains.size());
}
static A64CC::CondCodes IntCCToA64CC(ISD::CondCode CC) {
switch (CC) {
case ISD::SETEQ: return A64CC::EQ;
case ISD::SETGT: return A64CC::GT;
case ISD::SETGE: return A64CC::GE;
case ISD::SETLT: return A64CC::LT;
case ISD::SETLE: return A64CC::LE;
case ISD::SETNE: return A64CC::NE;
case ISD::SETUGT: return A64CC::HI;
case ISD::SETUGE: return A64CC::HS;
case ISD::SETULT: return A64CC::LO;
case ISD::SETULE: return A64CC::LS;
default: llvm_unreachable("Unexpected condition code");
}
}
bool AArch64TargetLowering::isLegalICmpImmediate(int64_t Val) const {
// icmp is implemented using adds/subs immediate, which take an unsigned
// 12-bit immediate, optionally shifted left by 12 bits.
// Symmetric by using adds/subs
if (Val < 0)
Val = -Val;
return (Val & ~0xfff) == 0 || (Val & ~0xfff000) == 0;
}
SDValue AArch64TargetLowering::getSelectableIntSetCC(SDValue LHS, SDValue RHS,
ISD::CondCode CC, SDValue &A64cc,
SelectionDAG &DAG, SDLoc &dl) const {
if (ConstantSDNode *RHSC = dyn_cast<ConstantSDNode>(RHS.getNode())) {
int64_t C = 0;
EVT VT = RHSC->getValueType(0);
bool knownInvalid = false;
// I'm not convinced the rest of LLVM handles these edge cases properly, but
// we can at least get it right.
if (isSignedIntSetCC(CC)) {
C = RHSC->getSExtValue();
} else if (RHSC->getZExtValue() > INT64_MAX) {
// A 64-bit constant not representable by a signed 64-bit integer is far
// too big to fit into a SUBS immediate anyway.
knownInvalid = true;
} else {
C = RHSC->getZExtValue();
}
if (!knownInvalid && !isLegalICmpImmediate(C)) {
// Constant does not fit, try adjusting it by one?
switch (CC) {
default: break;
case ISD::SETLT:
case ISD::SETGE:
if (isLegalICmpImmediate(C-1)) {
CC = (CC == ISD::SETLT) ? ISD::SETLE : ISD::SETGT;
RHS = DAG.getConstant(C-1, VT);
}
break;
case ISD::SETULT:
case ISD::SETUGE:
if (isLegalICmpImmediate(C-1)) {
CC = (CC == ISD::SETULT) ? ISD::SETULE : ISD::SETUGT;
RHS = DAG.getConstant(C-1, VT);
}
break;
case ISD::SETLE:
case ISD::SETGT:
if (isLegalICmpImmediate(C+1)) {
CC = (CC == ISD::SETLE) ? ISD::SETLT : ISD::SETGE;
RHS = DAG.getConstant(C+1, VT);
}
break;
case ISD::SETULE:
case ISD::SETUGT:
if (isLegalICmpImmediate(C+1)) {
CC = (CC == ISD::SETULE) ? ISD::SETULT : ISD::SETUGE;
RHS = DAG.getConstant(C+1, VT);
}
break;
}
}
}
A64CC::CondCodes CondCode = IntCCToA64CC(CC);
A64cc = DAG.getConstant(CondCode, MVT::i32);
return DAG.getNode(AArch64ISD::SETCC, dl, MVT::i32, LHS, RHS,
DAG.getCondCode(CC));
}
static A64CC::CondCodes FPCCToA64CC(ISD::CondCode CC,
A64CC::CondCodes &Alternative) {
A64CC::CondCodes CondCode = A64CC::Invalid;
Alternative = A64CC::Invalid;
switch (CC) {
default: llvm_unreachable("Unknown FP condition!");
case ISD::SETEQ:
case ISD::SETOEQ: CondCode = A64CC::EQ; break;
case ISD::SETGT:
case ISD::SETOGT: CondCode = A64CC::GT; break;
case ISD::SETGE:
case ISD::SETOGE: CondCode = A64CC::GE; break;
case ISD::SETOLT: CondCode = A64CC::MI; break;
case ISD::SETOLE: CondCode = A64CC::LS; break;
case ISD::SETONE: CondCode = A64CC::MI; Alternative = A64CC::GT; break;
case ISD::SETO: CondCode = A64CC::VC; break;
case ISD::SETUO: CondCode = A64CC::VS; break;
case ISD::SETUEQ: CondCode = A64CC::EQ; Alternative = A64CC::VS; break;
case ISD::SETUGT: CondCode = A64CC::HI; break;
case ISD::SETUGE: CondCode = A64CC::PL; break;
case ISD::SETLT:
case ISD::SETULT: CondCode = A64CC::LT; break;
case ISD::SETLE:
case ISD::SETULE: CondCode = A64CC::LE; break;
case ISD::SETNE:
case ISD::SETUNE: CondCode = A64CC::NE; break;
}
return CondCode;
}
SDValue
AArch64TargetLowering::LowerBlockAddress(SDValue Op, SelectionDAG &DAG) const {
SDLoc DL(Op);
EVT PtrVT = getPointerTy();
const BlockAddress *BA = cast<BlockAddressSDNode>(Op)->getBlockAddress();
switch(getTargetMachine().getCodeModel()) {
case CodeModel::Small:
// The most efficient code is PC-relative anyway for the small memory model,
// so we don't need to worry about relocation model.
return DAG.getNode(AArch64ISD::WrapperSmall, DL, PtrVT,
DAG.getTargetBlockAddress(BA, PtrVT, 0,
AArch64II::MO_NO_FLAG),
DAG.getTargetBlockAddress(BA, PtrVT, 0,
AArch64II::MO_LO12),
DAG.getConstant(/*Alignment=*/ 4, MVT::i32));
case CodeModel::Large:
return DAG.getNode(
AArch64ISD::WrapperLarge, DL, PtrVT,
DAG.getTargetBlockAddress(BA, PtrVT, 0, AArch64II::MO_ABS_G3),
DAG.getTargetBlockAddress(BA, PtrVT, 0, AArch64II::MO_ABS_G2_NC),
DAG.getTargetBlockAddress(BA, PtrVT, 0, AArch64II::MO_ABS_G1_NC),
DAG.getTargetBlockAddress(BA, PtrVT, 0, AArch64II::MO_ABS_G0_NC));
default:
llvm_unreachable("Only small and large code models supported now");
}
}
// (BRCOND chain, val, dest)
SDValue
AArch64TargetLowering::LowerBRCOND(SDValue Op, SelectionDAG &DAG) const {
SDLoc dl(Op);
SDValue Chain = Op.getOperand(0);
SDValue TheBit = Op.getOperand(1);
SDValue DestBB = Op.getOperand(2);
// AArch64 BooleanContents is the default UndefinedBooleanContent, which means
// that as the consumer we are responsible for ignoring rubbish in higher
// bits.
TheBit = DAG.getNode(ISD::AND, dl, MVT::i32, TheBit,
DAG.getConstant(1, MVT::i32));
SDValue A64CMP = DAG.getNode(AArch64ISD::SETCC, dl, MVT::i32, TheBit,
DAG.getConstant(0, TheBit.getValueType()),
DAG.getCondCode(ISD::SETNE));
return DAG.getNode(AArch64ISD::BR_CC, dl, MVT::Other, Chain,
A64CMP, DAG.getConstant(A64CC::NE, MVT::i32),
DestBB);
}
// (BR_CC chain, condcode, lhs, rhs, dest)
SDValue
AArch64TargetLowering::LowerBR_CC(SDValue Op, SelectionDAG &DAG) const {
SDLoc dl(Op);
SDValue Chain = Op.getOperand(0);
ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(1))->get();
SDValue LHS = Op.getOperand(2);
SDValue RHS = Op.getOperand(3);
SDValue DestBB = Op.getOperand(4);
if (LHS.getValueType() == MVT::f128) {
// f128 comparisons are lowered to runtime calls by a routine which sets
// LHS, RHS and CC appropriately for the rest of this function to continue.
softenSetCCOperands(DAG, MVT::f128, LHS, RHS, CC, dl);
// If softenSetCCOperands returned a scalar, we need to compare the result
// against zero to select between true and false values.
if (RHS.getNode() == 0) {
RHS = DAG.getConstant(0, LHS.getValueType());
CC = ISD::SETNE;
}
}
if (LHS.getValueType().isInteger()) {
SDValue A64cc;
// Integers are handled in a separate function because the combinations of
// immediates and tests can get hairy and we may want to fiddle things.
SDValue CmpOp = getSelectableIntSetCC(LHS, RHS, CC, A64cc, DAG, dl);
return DAG.getNode(AArch64ISD::BR_CC, dl, MVT::Other,
Chain, CmpOp, A64cc, DestBB);
}
// Note that some LLVM floating-point CondCodes can't be lowered to a single
// conditional branch, hence FPCCToA64CC can set a second test, where either
// passing is sufficient.
A64CC::CondCodes CondCode, Alternative = A64CC::Invalid;
CondCode = FPCCToA64CC(CC, Alternative);
SDValue A64cc = DAG.getConstant(CondCode, MVT::i32);
SDValue SetCC = DAG.getNode(AArch64ISD::SETCC, dl, MVT::i32, LHS, RHS,
DAG.getCondCode(CC));
SDValue A64BR_CC = DAG.getNode(AArch64ISD::BR_CC, dl, MVT::Other,
Chain, SetCC, A64cc, DestBB);
if (Alternative != A64CC::Invalid) {
A64cc = DAG.getConstant(Alternative, MVT::i32);
A64BR_CC = DAG.getNode(AArch64ISD::BR_CC, dl, MVT::Other,
A64BR_CC, SetCC, A64cc, DestBB);
}
return A64BR_CC;
}
SDValue
AArch64TargetLowering::LowerF128ToCall(SDValue Op, SelectionDAG &DAG,
RTLIB::Libcall Call) const {
ArgListTy Args;
ArgListEntry Entry;
for (unsigned i = 0, e = Op->getNumOperands(); i != e; ++i) {
EVT ArgVT = Op.getOperand(i).getValueType();
Type *ArgTy = ArgVT.getTypeForEVT(*DAG.getContext());
Entry.Node = Op.getOperand(i); Entry.Ty = ArgTy;
Entry.isSExt = false;
Entry.isZExt = false;
Args.push_back(Entry);
}
SDValue Callee = DAG.getExternalSymbol(getLibcallName(Call), getPointerTy());
Type *RetTy = Op.getValueType().getTypeForEVT(*DAG.getContext());
// By default, the input chain to this libcall is the entry node of the
// function. If the libcall is going to be emitted as a tail call then
// isUsedByReturnOnly will change it to the right chain if the return
// node which is being folded has a non-entry input chain.
SDValue InChain = DAG.getEntryNode();
// isTailCall may be true since the callee does not reference caller stack
// frame. Check if it's in the right position.
SDValue TCChain = InChain;
bool isTailCall = isInTailCallPosition(DAG, Op.getNode(), TCChain);
if (isTailCall)
InChain = TCChain;
TargetLowering::
CallLoweringInfo CLI(InChain, RetTy, false, false, false, false,
0, getLibcallCallingConv(Call), isTailCall,
/*doesNotReturn=*/false, /*isReturnValueUsed=*/true,
Callee, Args, DAG, SDLoc(Op));
std::pair<SDValue, SDValue> CallInfo = LowerCallTo(CLI);
if (!CallInfo.second.getNode())
// It's a tailcall, return the chain (which is the DAG root).
return DAG.getRoot();
return CallInfo.first;
}
SDValue
AArch64TargetLowering::LowerFP_ROUND(SDValue Op, SelectionDAG &DAG) const {
if (Op.getOperand(0).getValueType() != MVT::f128) {
// It's legal except when f128 is involved
return Op;
}
RTLIB::Libcall LC;
LC = RTLIB::getFPROUND(Op.getOperand(0).getValueType(), Op.getValueType());
SDValue SrcVal = Op.getOperand(0);
return makeLibCall(DAG, LC, Op.getValueType(), &SrcVal, 1,
/*isSigned*/ false, SDLoc(Op));
}
SDValue
AArch64TargetLowering::LowerFP_EXTEND(SDValue Op, SelectionDAG &DAG) const {
assert(Op.getValueType() == MVT::f128 && "Unexpected lowering");
RTLIB::Libcall LC;
LC = RTLIB::getFPEXT(Op.getOperand(0).getValueType(), Op.getValueType());
return LowerF128ToCall(Op, DAG, LC);
}
SDValue
AArch64TargetLowering::LowerFP_TO_INT(SDValue Op, SelectionDAG &DAG,
bool IsSigned) const {
if (Op.getOperand(0).getValueType() != MVT::f128) {
// It's legal except when f128 is involved
return Op;
}
RTLIB::Libcall LC;
if (IsSigned)
LC = RTLIB::getFPTOSINT(Op.getOperand(0).getValueType(), Op.getValueType());
else
LC = RTLIB::getFPTOUINT(Op.getOperand(0).getValueType(), Op.getValueType());
return LowerF128ToCall(Op, DAG, LC);
}
SDValue
AArch64TargetLowering::LowerGlobalAddressELFLarge(SDValue Op,
SelectionDAG &DAG) const {
assert(getTargetMachine().getCodeModel() == CodeModel::Large);
assert(getTargetMachine().getRelocationModel() == Reloc::Static);
EVT PtrVT = getPointerTy();
SDLoc dl(Op);
const GlobalAddressSDNode *GN = cast<GlobalAddressSDNode>(Op);
const GlobalValue *GV = GN->getGlobal();
SDValue GlobalAddr = DAG.getNode(
AArch64ISD::WrapperLarge, dl, PtrVT,
DAG.getTargetGlobalAddress(GV, dl, PtrVT, 0, AArch64II::MO_ABS_G3),
DAG.getTargetGlobalAddress(GV, dl, PtrVT, 0, AArch64II::MO_ABS_G2_NC),
DAG.getTargetGlobalAddress(GV, dl, PtrVT, 0, AArch64II::MO_ABS_G1_NC),
DAG.getTargetGlobalAddress(GV, dl, PtrVT, 0, AArch64II::MO_ABS_G0_NC));
if (GN->getOffset() != 0)
return DAG.getNode(ISD::ADD, dl, PtrVT, GlobalAddr,
DAG.getConstant(GN->getOffset(), PtrVT));
return GlobalAddr;
}
SDValue
AArch64TargetLowering::LowerGlobalAddressELFSmall(SDValue Op,
SelectionDAG &DAG) const {
assert(getTargetMachine().getCodeModel() == CodeModel::Small);
EVT PtrVT = getPointerTy();
SDLoc dl(Op);
const GlobalAddressSDNode *GN = cast<GlobalAddressSDNode>(Op);
const GlobalValue *GV = GN->getGlobal();
unsigned Alignment = GV->getAlignment();
Reloc::Model RelocM = getTargetMachine().getRelocationModel();
if (GV->isWeakForLinker() && GV->isDeclaration() && RelocM == Reloc::Static) {
// Weak undefined symbols can't use ADRP/ADD pair since they should evaluate
// to zero when they remain undefined. In PIC mode the GOT can take care of
// this, but in absolute mode we use a constant pool load.
SDValue PoolAddr;
PoolAddr = DAG.getNode(AArch64ISD::WrapperSmall, dl, PtrVT,
DAG.getTargetConstantPool(GV, PtrVT, 0, 0,
AArch64II::MO_NO_FLAG),
DAG.getTargetConstantPool(GV, PtrVT, 0, 0,
AArch64II::MO_LO12),
DAG.getConstant(8, MVT::i32));
SDValue GlobalAddr = DAG.getLoad(PtrVT, dl, DAG.getEntryNode(), PoolAddr,
MachinePointerInfo::getConstantPool(),
/*isVolatile=*/ false,
/*isNonTemporal=*/ true,
/*isInvariant=*/ true, 8);
if (GN->getOffset() != 0)
return DAG.getNode(ISD::ADD, dl, PtrVT, GlobalAddr,
DAG.getConstant(GN->getOffset(), PtrVT));
return GlobalAddr;
}
if (Alignment == 0) {
const PointerType *GVPtrTy = cast<PointerType>(GV->getType());
if (GVPtrTy->getElementType()->isSized()) {
Alignment
= getDataLayout()->getABITypeAlignment(GVPtrTy->getElementType());
} else {
// Be conservative if we can't guess, not that it really matters:
// functions and labels aren't valid for loads, and the methods used to
// actually calculate an address work with any alignment.
Alignment = 1;
}
}
unsigned char HiFixup, LoFixup;
bool UseGOT = getSubtarget()->GVIsIndirectSymbol(GV, RelocM);
if (UseGOT) {
HiFixup = AArch64II::MO_GOT;
LoFixup = AArch64II::MO_GOT_LO12;
Alignment = 8;
} else {
HiFixup = AArch64II::MO_NO_FLAG;
LoFixup = AArch64II::MO_LO12;
}
// AArch64's small model demands the following sequence:
// ADRP x0, somewhere
// ADD x0, x0, #:lo12:somewhere ; (or LDR directly).
SDValue GlobalRef = DAG.getNode(AArch64ISD::WrapperSmall, dl, PtrVT,
DAG.getTargetGlobalAddress(GV, dl, PtrVT, 0,
HiFixup),
DAG.getTargetGlobalAddress(GV, dl, PtrVT, 0,
LoFixup),
DAG.getConstant(Alignment, MVT::i32));
if (UseGOT) {
GlobalRef = DAG.getNode(AArch64ISD::GOTLoad, dl, PtrVT, DAG.getEntryNode(),
GlobalRef);
}
if (GN->getOffset() != 0)
return DAG.getNode(ISD::ADD, dl, PtrVT, GlobalRef,
DAG.getConstant(GN->getOffset(), PtrVT));
return GlobalRef;
}
SDValue
AArch64TargetLowering::LowerGlobalAddressELF(SDValue Op,
SelectionDAG &DAG) const {
// TableGen doesn't have easy access to the CodeModel or RelocationModel, so
// we make those distinctions here.
switch (getTargetMachine().getCodeModel()) {
case CodeModel::Small:
return LowerGlobalAddressELFSmall(Op, DAG);
case CodeModel::Large:
return LowerGlobalAddressELFLarge(Op, DAG);
default:
llvm_unreachable("Only small and large code models supported now");
}
}
SDValue AArch64TargetLowering::LowerTLSDescCall(SDValue SymAddr,
SDValue DescAddr,
SDLoc DL,
SelectionDAG &DAG) const {
EVT PtrVT = getPointerTy();
// The function we need to call is simply the first entry in the GOT for this
// descriptor, load it in preparation.
SDValue Func, Chain;
Func = DAG.getNode(AArch64ISD::GOTLoad, DL, PtrVT, DAG.getEntryNode(),
DescAddr);
// The function takes only one argument: the address of the descriptor itself
// in X0.
SDValue Glue;
Chain = DAG.getCopyToReg(DAG.getEntryNode(), DL, AArch64::X0, DescAddr, Glue);
Glue = Chain.getValue(1);
// Finally, there's a special calling-convention which means that the lookup
// must preserve all registers (except X0, obviously).
const TargetRegisterInfo *TRI = getTargetMachine().getRegisterInfo();
const AArch64RegisterInfo *A64RI
= static_cast<const AArch64RegisterInfo *>(TRI);
const uint32_t *Mask = A64RI->getTLSDescCallPreservedMask();
// We're now ready to populate the argument list, as with a normal call:
std::vector<SDValue> Ops;
Ops.push_back(Chain);
Ops.push_back(Func);
Ops.push_back(SymAddr);
Ops.push_back(DAG.getRegister(AArch64::X0, PtrVT));
Ops.push_back(DAG.getRegisterMask(Mask));
Ops.push_back(Glue);
SDVTList NodeTys = DAG.getVTList(MVT::Other, MVT::Glue);
Chain = DAG.getNode(AArch64ISD::TLSDESCCALL, DL, NodeTys, &Ops[0],
Ops.size());
Glue = Chain.getValue(1);
// After the call, the offset from TPIDR_EL0 is in X0, copy it out and pass it
// back to the generic handling code.
return DAG.getCopyFromReg(Chain, DL, AArch64::X0, PtrVT, Glue);
}
SDValue
AArch64TargetLowering::LowerGlobalTLSAddress(SDValue Op,
SelectionDAG &DAG) const {
assert(getSubtarget()->isTargetELF() &&
"TLS not implemented for non-ELF targets");
assert(getTargetMachine().getCodeModel() == CodeModel::Small
&& "TLS only supported in small memory model");
const GlobalAddressSDNode *GA = cast<GlobalAddressSDNode>(Op);
TLSModel::Model Model = getTargetMachine().getTLSModel(GA->getGlobal());
SDValue TPOff;
EVT PtrVT = getPointerTy();
SDLoc DL(Op);
const GlobalValue *GV = GA->getGlobal();
SDValue ThreadBase = DAG.getNode(AArch64ISD::THREAD_POINTER, DL, PtrVT);
if (Model == TLSModel::InitialExec) {
TPOff = DAG.getNode(AArch64ISD::WrapperSmall, DL, PtrVT,
DAG.getTargetGlobalAddress(GV, DL, PtrVT, 0,
AArch64II::MO_GOTTPREL),
DAG.getTargetGlobalAddress(GV, DL, PtrVT, 0,
AArch64II::MO_GOTTPREL_LO12),
DAG.getConstant(8, MVT::i32));
TPOff = DAG.getNode(AArch64ISD::GOTLoad, DL, PtrVT, DAG.getEntryNode(),
TPOff);
} else if (Model == TLSModel::LocalExec) {
SDValue HiVar = DAG.getTargetGlobalAddress(GV, DL, MVT::i64, 0,
AArch64II::MO_TPREL_G1);
SDValue LoVar = DAG.getTargetGlobalAddress(GV, DL, MVT::i64, 0,
AArch64II::MO_TPREL_G0_NC);
TPOff = SDValue(DAG.getMachineNode(AArch64::MOVZxii, DL, PtrVT, HiVar,
DAG.getTargetConstant(0, MVT::i32)), 0);
TPOff = SDValue(DAG.getMachineNode(AArch64::MOVKxii, DL, PtrVT,
TPOff, LoVar,
DAG.getTargetConstant(0, MVT::i32)), 0);
} else if (Model == TLSModel::GeneralDynamic) {
// Accesses used in this sequence go via the TLS descriptor which lives in
// the GOT. Prepare an address we can use to handle this.
SDValue HiDesc = DAG.getTargetGlobalAddress(GV, DL, PtrVT, 0,
AArch64II::MO_TLSDESC);
SDValue LoDesc = DAG.getTargetGlobalAddress(GV, DL, PtrVT, 0,
AArch64II::MO_TLSDESC_LO12);
SDValue DescAddr = DAG.getNode(AArch64ISD::WrapperSmall, DL, PtrVT,
HiDesc, LoDesc,
DAG.getConstant(8, MVT::i32));
SDValue SymAddr = DAG.getTargetGlobalAddress(GV, DL, PtrVT, 0);
TPOff = LowerTLSDescCall(SymAddr, DescAddr, DL, DAG);
} else if (Model == TLSModel::LocalDynamic) {
// Local-dynamic accesses proceed in two phases. A general-dynamic TLS
// descriptor call against the special symbol _TLS_MODULE_BASE_ to calculate
// the beginning of the module's TLS region, followed by a DTPREL offset
// calculation.
// These accesses will need deduplicating if there's more than one.
AArch64MachineFunctionInfo* MFI = DAG.getMachineFunction()
.getInfo<AArch64MachineFunctionInfo>();
MFI->incNumLocalDynamicTLSAccesses();
// Get the location of _TLS_MODULE_BASE_:
SDValue HiDesc = DAG.getTargetExternalSymbol("_TLS_MODULE_BASE_", PtrVT,
AArch64II::MO_TLSDESC);
SDValue LoDesc = DAG.getTargetExternalSymbol("_TLS_MODULE_BASE_", PtrVT,
AArch64II::MO_TLSDESC_LO12);
SDValue DescAddr = DAG.getNode(AArch64ISD::WrapperSmall, DL, PtrVT,
HiDesc, LoDesc,
DAG.getConstant(8, MVT::i32));
SDValue SymAddr = DAG.getTargetExternalSymbol("_TLS_MODULE_BASE_", PtrVT);
ThreadBase = LowerTLSDescCall(SymAddr, DescAddr, DL, DAG);
// Get the variable's offset from _TLS_MODULE_BASE_
SDValue HiVar = DAG.getTargetGlobalAddress(GV, DL, MVT::i64, 0,
AArch64II::MO_DTPREL_G1);
SDValue LoVar = DAG.getTargetGlobalAddress(GV, DL, MVT::i64, 0,
AArch64II::MO_DTPREL_G0_NC);
TPOff = SDValue(DAG.getMachineNode(AArch64::MOVZxii, DL, PtrVT, HiVar,
DAG.getTargetConstant(0, MVT::i32)), 0);
TPOff = SDValue(DAG.getMachineNode(AArch64::MOVKxii, DL, PtrVT,
TPOff, LoVar,
DAG.getTargetConstant(0, MVT::i32)), 0);
} else
llvm_unreachable("Unsupported TLS access model");
return DAG.getNode(ISD::ADD, DL, PtrVT, ThreadBase, TPOff);
}
SDValue
AArch64TargetLowering::LowerINT_TO_FP(SDValue Op, SelectionDAG &DAG,
bool IsSigned) const {
if (Op.getValueType() != MVT::f128) {
// Legal for everything except f128.
return Op;
}
RTLIB::Libcall LC;
if (IsSigned)
LC = RTLIB::getSINTTOFP(Op.getOperand(0).getValueType(), Op.getValueType());
else
LC = RTLIB::getUINTTOFP(Op.getOperand(0).getValueType(), Op.getValueType());
return LowerF128ToCall(Op, DAG, LC);
}
SDValue
AArch64TargetLowering::LowerJumpTable(SDValue Op, SelectionDAG &DAG) const {
JumpTableSDNode *JT = cast<JumpTableSDNode>(Op);
SDLoc dl(JT);
EVT PtrVT = getPointerTy();
// When compiling PIC, jump tables get put in the code section so a static
// relocation-style is acceptable for both cases.
switch (getTargetMachine().getCodeModel()) {
case CodeModel::Small:
return DAG.getNode(AArch64ISD::WrapperSmall, dl, PtrVT,
DAG.getTargetJumpTable(JT->getIndex(), PtrVT),
DAG.getTargetJumpTable(JT->getIndex(), PtrVT,
AArch64II::MO_LO12),
DAG.getConstant(1, MVT::i32));
case CodeModel::Large:
return DAG.getNode(
AArch64ISD::WrapperLarge, dl, PtrVT,
DAG.getTargetJumpTable(JT->getIndex(), PtrVT, AArch64II::MO_ABS_G3),
DAG.getTargetJumpTable(JT->getIndex(), PtrVT, AArch64II::MO_ABS_G2_NC),
DAG.getTargetJumpTable(JT->getIndex(), PtrVT, AArch64II::MO_ABS_G1_NC),
DAG.getTargetJumpTable(JT->getIndex(), PtrVT, AArch64II::MO_ABS_G0_NC));
default:
llvm_unreachable("Only small and large code models supported now");
}
}
// (SELECT_CC lhs, rhs, iftrue, iffalse, condcode)
SDValue
AArch64TargetLowering::LowerSELECT_CC(SDValue Op, SelectionDAG &DAG) const {
SDLoc dl(Op);
SDValue LHS = Op.getOperand(0);
SDValue RHS = Op.getOperand(1);
SDValue IfTrue = Op.getOperand(2);
SDValue IfFalse = Op.getOperand(3);
ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(4))->get();
if (LHS.getValueType() == MVT::f128) {
// f128 comparisons are lowered to libcalls, but slot in nicely here
// afterwards.
softenSetCCOperands(DAG, MVT::f128, LHS, RHS, CC, dl);
// If softenSetCCOperands returned a scalar, we need to compare the result
// against zero to select between true and false values.
if (RHS.getNode() == 0) {
RHS = DAG.getConstant(0, LHS.getValueType());
CC = ISD::SETNE;
}
}
if (LHS.getValueType().isInteger()) {
SDValue A64cc;
// Integers are handled in a separate function because the combinations of
// immediates and tests can get hairy and we may want to fiddle things.
SDValue CmpOp = getSelectableIntSetCC(LHS, RHS, CC, A64cc, DAG, dl);
return DAG.getNode(AArch64ISD::SELECT_CC, dl, Op.getValueType(),
CmpOp, IfTrue, IfFalse, A64cc);
}
// Note that some LLVM floating-point CondCodes can't be lowered to a single
// conditional branch, hence FPCCToA64CC can set a second test, where either
// passing is sufficient.
A64CC::CondCodes CondCode, Alternative = A64CC::Invalid;
CondCode = FPCCToA64CC(CC, Alternative);
SDValue A64cc = DAG.getConstant(CondCode, MVT::i32);
SDValue SetCC = DAG.getNode(AArch64ISD::SETCC, dl, MVT::i32, LHS, RHS,
DAG.getCondCode(CC));
SDValue A64SELECT_CC = DAG.getNode(AArch64ISD::SELECT_CC, dl,
Op.getValueType(),
SetCC, IfTrue, IfFalse, A64cc);
if (Alternative != A64CC::Invalid) {
A64cc = DAG.getConstant(Alternative, MVT::i32);
A64SELECT_CC = DAG.getNode(AArch64ISD::SELECT_CC, dl, Op.getValueType(),
SetCC, IfTrue, A64SELECT_CC, A64cc);
}
return A64SELECT_CC;
}
// (SELECT testbit, iftrue, iffalse)
SDValue
AArch64TargetLowering::LowerSELECT(SDValue Op, SelectionDAG &DAG) const {
SDLoc dl(Op);
SDValue TheBit = Op.getOperand(0);
SDValue IfTrue = Op.getOperand(1);
SDValue IfFalse = Op.getOperand(2);
// AArch64 BooleanContents is the default UndefinedBooleanContent, which means
// that as the consumer we are responsible for ignoring rubbish in higher
// bits.
TheBit = DAG.getNode(ISD::AND, dl, MVT::i32, TheBit,
DAG.getConstant(1, MVT::i32));
SDValue A64CMP = DAG.getNode(AArch64ISD::SETCC, dl, MVT::i32, TheBit,
DAG.getConstant(0, TheBit.getValueType()),
DAG.getCondCode(ISD::SETNE));
return DAG.getNode(AArch64ISD::SELECT_CC, dl, Op.getValueType(),
A64CMP, IfTrue, IfFalse,
DAG.getConstant(A64CC::NE, MVT::i32));
}
// (SETCC lhs, rhs, condcode)
SDValue
AArch64TargetLowering::LowerSETCC(SDValue Op, SelectionDAG &DAG) const {
SDLoc dl(Op);
SDValue LHS = Op.getOperand(0);
SDValue RHS = Op.getOperand(1);
ISD::CondCode CC = cast<CondCodeSDNode>(Op.getOperand(2))->get();
EVT VT = Op.getValueType();
if (LHS.getValueType() == MVT::f128) {
// f128 comparisons will be lowered to libcalls giving a valid LHS and RHS
// for the rest of the function (some i32 or i64 values).
softenSetCCOperands(DAG, MVT::f128, LHS, RHS, CC, dl);
// If softenSetCCOperands returned a scalar, use it.
if (RHS.getNode() == 0) {
assert(LHS.getValueType() == Op.getValueType() &&
"Unexpected setcc expansion!");
return LHS;
}
}
if (LHS.getValueType().isInteger()) {
SDValue A64cc;
// Integers are handled in a separate function because the combinations of
// immediates and tests can get hairy and we may want to fiddle things.
SDValue CmpOp = getSelectableIntSetCC(LHS, RHS, CC, A64cc, DAG, dl);
return DAG.getNode(AArch64ISD::SELECT_CC, dl, VT,
CmpOp, DAG.getConstant(1, VT), DAG.getConstant(0, VT),
A64cc);
}
// Note that some LLVM floating-point CondCodes can't be lowered to a single
// conditional branch, hence FPCCToA64CC can set a second test, where either
// passing is sufficient.
A64CC::CondCodes CondCode, Alternative = A64CC::Invalid;
CondCode = FPCCToA64CC(CC, Alternative);
SDValue A64cc = DAG.getConstant(CondCode, MVT::i32);
SDValue CmpOp = DAG.getNode(AArch64ISD::SETCC, dl, MVT::i32, LHS, RHS,
DAG.getCondCode(CC));
SDValue A64SELECT_CC = DAG.getNode(AArch64ISD::SELECT_CC, dl, VT,
CmpOp, DAG.getConstant(1, VT),
DAG.getConstant(0, VT), A64cc);
if (Alternative != A64CC::Invalid) {
A64cc = DAG.getConstant(Alternative, MVT::i32);
A64SELECT_CC = DAG.getNode(AArch64ISD::SELECT_CC, dl, VT, CmpOp,
DAG.getConstant(1, VT), A64SELECT_CC, A64cc);
}
return A64SELECT_CC;
}
SDValue
AArch64TargetLowering::LowerVACOPY(SDValue Op, SelectionDAG &DAG) const {
const Value *DestSV = cast<SrcValueSDNode>(Op.getOperand(3))->getValue();
const Value *SrcSV = cast<SrcValueSDNode>(Op.getOperand(3))->getValue();
// We have to make sure we copy the entire structure: 8+8+8+4+4 = 32 bytes
// rather than just 8.
return DAG.getMemcpy(Op.getOperand(0), SDLoc(Op),
Op.getOperand(1), Op.getOperand(2),
DAG.getConstant(32, MVT::i32), 8, false, false,
MachinePointerInfo(DestSV), MachinePointerInfo(SrcSV));
}
SDValue
AArch64TargetLowering::LowerVASTART(SDValue Op, SelectionDAG &DAG) const {
// The layout of the va_list struct is specified in the AArch64 Procedure Call
// Standard, section B.3.
MachineFunction &MF = DAG.getMachineFunction();
AArch64MachineFunctionInfo *FuncInfo
= MF.getInfo<AArch64MachineFunctionInfo>();
SDLoc DL(Op);
SDValue Chain = Op.getOperand(0);
SDValue VAList = Op.getOperand(1);
const Value *SV = cast<SrcValueSDNode>(Op.getOperand(2))->getValue();
SmallVector<SDValue, 4> MemOps;
// void *__stack at offset 0
SDValue Stack = DAG.getFrameIndex(FuncInfo->getVariadicStackIdx(),
getPointerTy());
MemOps.push_back(DAG.getStore(Chain, DL, Stack, VAList,
MachinePointerInfo(SV), false, false, 0));
// void *__gr_top at offset 8
int GPRSize = FuncInfo->getVariadicGPRSize();
if (GPRSize > 0) {
SDValue GRTop, GRTopAddr;
GRTopAddr = DAG.getNode(ISD::ADD, DL, getPointerTy(), VAList,
DAG.getConstant(8, getPointerTy()));
GRTop = DAG.getFrameIndex(FuncInfo->getVariadicGPRIdx(), getPointerTy());
GRTop = DAG.getNode(ISD::ADD, DL, getPointerTy(), GRTop,
DAG.getConstant(GPRSize, getPointerTy()));
MemOps.push_back(DAG.getStore(Chain, DL, GRTop, GRTopAddr,
MachinePointerInfo(SV, 8),
false, false, 0));
}
// void *__vr_top at offset 16
int FPRSize = FuncInfo->getVariadicFPRSize();
if (FPRSize > 0) {
SDValue VRTop, VRTopAddr;
VRTopAddr = DAG.getNode(ISD::ADD, DL, getPointerTy(), VAList,
DAG.getConstant(16, getPointerTy()));
VRTop = DAG.getFrameIndex(FuncInfo->getVariadicFPRIdx(), getPointerTy());
VRTop = DAG.getNode(ISD::ADD, DL, getPointerTy(), VRTop,
DAG.getConstant(FPRSize, getPointerTy()));
MemOps.push_back(DAG.getStore(Chain, DL, VRTop, VRTopAddr,
MachinePointerInfo(SV, 16),
false, false, 0));
}
// int __gr_offs at offset 24
SDValue GROffsAddr = DAG.getNode(ISD::ADD, DL, getPointerTy(), VAList,
DAG.getConstant(24, getPointerTy()));
MemOps.push_back(DAG.getStore(Chain, DL, DAG.getConstant(-GPRSize, MVT::i32),
GROffsAddr, MachinePointerInfo(SV, 24),
false, false, 0));
// int __vr_offs at offset 28
SDValue VROffsAddr = DAG.getNode(ISD::ADD, DL, getPointerTy(), VAList,
DAG.getConstant(28, getPointerTy()));
MemOps.push_back(DAG.getStore(Chain, DL, DAG.getConstant(-FPRSize, MVT::i32),
VROffsAddr, MachinePointerInfo(SV, 28),
false, false, 0));
return DAG.getNode(ISD::TokenFactor, DL, MVT::Other, &MemOps[0],
MemOps.size());
}
SDValue
AArch64TargetLowering::LowerOperation(SDValue Op, SelectionDAG &DAG) const {
switch (Op.getOpcode()) {
default: llvm_unreachable("Don't know how to custom lower this!");
case ISD::FADD: return LowerF128ToCall(Op, DAG, RTLIB::ADD_F128);
case ISD::FSUB: return LowerF128ToCall(Op, DAG, RTLIB::SUB_F128);
case ISD::FMUL: return LowerF128ToCall(Op, DAG, RTLIB::MUL_F128);
case ISD::FDIV: return LowerF128ToCall(Op, DAG, RTLIB::DIV_F128);
case ISD::FP_TO_SINT: return LowerFP_TO_INT(Op, DAG, true);
case ISD::FP_TO_UINT: return LowerFP_TO_INT(Op, DAG, false);
case ISD::SINT_TO_FP: return LowerINT_TO_FP(Op, DAG, true);
case ISD::UINT_TO_FP: return LowerINT_TO_FP(Op, DAG, false);
case ISD::FP_ROUND: return LowerFP_ROUND(Op, DAG);
case ISD::FP_EXTEND: return LowerFP_EXTEND(Op, DAG);
case ISD::BlockAddress: return LowerBlockAddress(Op, DAG);
case ISD::BRCOND: return LowerBRCOND(Op, DAG);
case ISD::BR_CC: return LowerBR_CC(Op, DAG);
case ISD::GlobalAddress: return LowerGlobalAddressELF(Op, DAG);
case ISD::GlobalTLSAddress: return LowerGlobalTLSAddress(Op, DAG);
case ISD::JumpTable: return LowerJumpTable(Op, DAG);
case ISD::SELECT: return LowerSELECT(Op, DAG);
case ISD::SELECT_CC: return LowerSELECT_CC(Op, DAG);
case ISD::SETCC: return LowerSETCC(Op, DAG);
case ISD::VACOPY: return LowerVACOPY(Op, DAG);
case ISD::VASTART: return LowerVASTART(Op, DAG);
}
return SDValue();
}
static SDValue PerformANDCombine(SDNode *N,
TargetLowering::DAGCombinerInfo &DCI) {
SelectionDAG &DAG = DCI.DAG;
SDLoc DL(N);
EVT VT = N->getValueType(0);
// We're looking for an SRA/SHL pair which form an SBFX.
if (VT != MVT::i32 && VT != MVT::i64)
return SDValue();
if (!isa<ConstantSDNode>(N->getOperand(1)))
return SDValue();
uint64_t TruncMask = N->getConstantOperandVal(1);
if (!isMask_64(TruncMask))
return SDValue();
uint64_t Width = CountPopulation_64(TruncMask);
SDValue Shift = N->getOperand(0);
if (Shift.getOpcode() != ISD::SRL)
return SDValue();
if (!isa<ConstantSDNode>(Shift->getOperand(1)))
return SDValue();
uint64_t LSB = Shift->getConstantOperandVal(1);
if (LSB > VT.getSizeInBits() || Width > VT.getSizeInBits())
return SDValue();
return DAG.getNode(AArch64ISD::UBFX, DL, VT, Shift.getOperand(0),
DAG.getConstant(LSB, MVT::i64),
DAG.getConstant(LSB + Width - 1, MVT::i64));
}
/// For a true bitfield insert, the bits getting into that contiguous mask
/// should come from the low part of an existing value: they must be formed from
/// a compatible SHL operation (unless they're already low). This function
/// checks that condition and returns the least-significant bit that's
/// intended. If the operation not a field preparation, -1 is returned.
static int32_t getLSBForBFI(SelectionDAG &DAG, SDLoc DL, EVT VT,
SDValue &MaskedVal, uint64_t Mask) {
if (!isShiftedMask_64(Mask))
return -1;
// Now we need to alter MaskedVal so that it is an appropriate input for a BFI
// instruction. BFI will do a left-shift by LSB before applying the mask we've
// spotted, so in general we should pre-emptively "undo" that by making sure
// the incoming bits have had a right-shift applied to them.
//
// This right shift, however, will combine with existing left/right shifts. In
// the simplest case of a completely straight bitfield operation, it will be
// expected to completely cancel out with an existing SHL. More complicated
// cases (e.g. bitfield to bitfield copy) may still need a real shift before
// the BFI.
uint64_t LSB = countTrailingZeros(Mask);
int64_t ShiftRightRequired = LSB;
if (MaskedVal.getOpcode() == ISD::SHL &&
isa<ConstantSDNode>(MaskedVal.getOperand(1))) {
ShiftRightRequired -= MaskedVal.getConstantOperandVal(1);
MaskedVal = MaskedVal.getOperand(0);
} else if (MaskedVal.getOpcode() == ISD::SRL &&
isa<ConstantSDNode>(MaskedVal.getOperand(1))) {
ShiftRightRequired += MaskedVal.getConstantOperandVal(1);
MaskedVal = MaskedVal.getOperand(0);
}
if (ShiftRightRequired > 0)
MaskedVal = DAG.getNode(ISD::SRL, DL, VT, MaskedVal,
DAG.getConstant(ShiftRightRequired, MVT::i64));
else if (ShiftRightRequired < 0) {
// We could actually end up with a residual left shift, for example with
// "struc.bitfield = val << 1".
MaskedVal = DAG.getNode(ISD::SHL, DL, VT, MaskedVal,
DAG.getConstant(-ShiftRightRequired, MVT::i64));
}
return LSB;
}
/// Searches from N for an existing AArch64ISD::BFI node, possibly surrounded by
/// a mask and an extension. Returns true if a BFI was found and provides
/// information on its surroundings.
static bool findMaskedBFI(SDValue N, SDValue &BFI, uint64_t &Mask,
bool &Extended) {
Extended = false;
if (N.getOpcode() == ISD::ZERO_EXTEND) {
Extended = true;
N = N.getOperand(0);
}
if (N.getOpcode() == ISD::AND && isa<ConstantSDNode>(N.getOperand(1))) {
Mask = N->getConstantOperandVal(1);
N = N.getOperand(0);
} else {
// Mask is the whole width.
Mask = -1ULL >> (64 - N.getValueType().getSizeInBits());
}
if (N.getOpcode() == AArch64ISD::BFI) {
BFI = N;
return true;
}
return false;
}
/// Try to combine a subtree (rooted at an OR) into a "masked BFI" node, which
/// is roughly equivalent to (and (BFI ...), mask). This form is used because it
/// can often be further combined with a larger mask. Ultimately, we want mask
/// to be 2^32-1 or 2^64-1 so the AND can be skipped.
static SDValue tryCombineToBFI(SDNode *N,
TargetLowering::DAGCombinerInfo &DCI,
const AArch64Subtarget *Subtarget) {
SelectionDAG &DAG = DCI.DAG;
SDLoc DL(N);
EVT VT = N->getValueType(0);
assert(N->getOpcode() == ISD::OR && "Unexpected root");
// We need the LHS to be (and SOMETHING, MASK). Find out what that mask is or
// abandon the effort.
SDValue LHS = N->getOperand(0);
if (LHS.getOpcode() != ISD::AND)
return SDValue();
uint64_t LHSMask;
if (isa<ConstantSDNode>(LHS.getOperand(1)))
LHSMask = LHS->getConstantOperandVal(1);
else
return SDValue();
// We also need the RHS to be (and SOMETHING, MASK). Find out what that mask
// is or abandon the effort.
SDValue RHS = N->getOperand(1);
if (RHS.getOpcode() != ISD::AND)
return SDValue();
uint64_t RHSMask;
if (isa<ConstantSDNode>(RHS.getOperand(1)))
RHSMask = RHS->getConstantOperandVal(1);
else
return SDValue();
// Can't do anything if the masks are incompatible.
if (LHSMask & RHSMask)
return SDValue();
// Now we need one of the masks to be a contiguous field. Without loss of
// generality that should be the RHS one.
SDValue Bitfield = LHS.getOperand(0);
if (getLSBForBFI(DAG, DL, VT, Bitfield, LHSMask) != -1) {
// We know that LHS is a candidate new value, and RHS isn't already a better
// one.
std::swap(LHS, RHS);
std::swap(LHSMask, RHSMask);
}
// We've done our best to put the right operands in the right places, all we
// can do now is check whether a BFI exists.
Bitfield = RHS.getOperand(0);
int32_t LSB = getLSBForBFI(DAG, DL, VT, Bitfield, RHSMask);
if (LSB == -1)
return SDValue();
uint32_t Width = CountPopulation_64(RHSMask);
assert(Width && "Expected non-zero bitfield width");
SDValue BFI = DAG.getNode(AArch64ISD::BFI, DL, VT,
LHS.getOperand(0), Bitfield,
DAG.getConstant(LSB, MVT::i64),
DAG.getConstant(Width, MVT::i64));
// Mask is trivial
if ((LHSMask | RHSMask) == (-1ULL >> (64 - VT.getSizeInBits())))
return BFI;
return DAG.getNode(ISD::AND, DL, VT, BFI,
DAG.getConstant(LHSMask | RHSMask, VT));
}
/// Search for the bitwise combining (with careful masks) of a MaskedBFI and its
/// original input. This is surprisingly common because SROA splits things up
/// into i8 chunks, so the originally detected MaskedBFI may actually only act
/// on the low (say) byte of a word. This is then orred into the rest of the
/// word afterwards.
///
/// Basic input: (or (and OLDFIELD, MASK1), (MaskedBFI MASK2, OLDFIELD, ...)).
///
/// If MASK1 and MASK2 are compatible, we can fold the whole thing into the
/// MaskedBFI. We can also deal with a certain amount of extend/truncate being
/// involved.
static SDValue tryCombineToLargerBFI(SDNode *N,
TargetLowering::DAGCombinerInfo &DCI,
const AArch64Subtarget *Subtarget) {
SelectionDAG &DAG = DCI.DAG;
SDLoc DL(N);
EVT VT = N->getValueType(0);
// First job is to hunt for a MaskedBFI on either the left or right. Swap
// operands if it's actually on the right.
SDValue BFI;
SDValue PossExtraMask;
uint64_t ExistingMask = 0;
bool Extended = false;
if (findMaskedBFI(N->getOperand(0), BFI, ExistingMask, Extended))
PossExtraMask = N->getOperand(1);
else if (findMaskedBFI(N->getOperand(1), BFI, ExistingMask, Extended))
PossExtraMask = N->getOperand(0);
else
return SDValue();
// We can only combine a BFI with another compatible mask.
if (PossExtraMask.getOpcode() != ISD::AND ||
!isa<ConstantSDNode>(PossExtraMask.getOperand(1)))
return SDValue();
uint64_t ExtraMask = PossExtraMask->getConstantOperandVal(1);
// Masks must be compatible.
if (ExtraMask & ExistingMask)
return SDValue();
SDValue OldBFIVal = BFI.getOperand(0);
SDValue NewBFIVal = BFI.getOperand(1);
if (Extended) {
// We skipped a ZERO_EXTEND above, so the input to the MaskedBFIs should be
// 32-bit and we'll be forming a 64-bit MaskedBFI. The MaskedBFI arguments
// need to be made compatible.
assert(VT == MVT::i64 && BFI.getValueType() == MVT::i32
&& "Invalid types for BFI");
OldBFIVal = DAG.getNode(ISD::ANY_EXTEND, DL, VT, OldBFIVal);
NewBFIVal = DAG.getNode(ISD::ANY_EXTEND, DL, VT, NewBFIVal);
}
// We need the MaskedBFI to be combined with a mask of the *same* value.
if (PossExtraMask.getOperand(0) != OldBFIVal)
return SDValue();
BFI = DAG.getNode(AArch64ISD::BFI, DL, VT,
OldBFIVal, NewBFIVal,
BFI.getOperand(2), BFI.getOperand(3));
// If the masking is trivial, we don't need to create it.
if ((ExtraMask | ExistingMask) == (-1ULL >> (64 - VT.getSizeInBits())))
return BFI;
return DAG.getNode(ISD::AND, DL, VT, BFI,
DAG.getConstant(ExtraMask | ExistingMask, VT));
}
/// An EXTR instruction is made up of two shifts, ORed together. This helper
/// searches for and classifies those shifts.
static bool findEXTRHalf(SDValue N, SDValue &Src, uint32_t &ShiftAmount,
bool &FromHi) {
if (N.getOpcode() == ISD::SHL)
FromHi = false;
else if (N.getOpcode() == ISD::SRL)
FromHi = true;
else
return false;
if (!isa<ConstantSDNode>(N.getOperand(1)))
return false;
ShiftAmount = N->getConstantOperandVal(1);
Src = N->getOperand(0);
return true;
}
/// EXTR instruction extracts a contiguous chunk of bits from two existing
/// registers viewed as a high/low pair. This function looks for the pattern:
/// (or (shl VAL1, #N), (srl VAL2, #RegWidth-N)) and replaces it with an
/// EXTR. Can't quite be done in TableGen because the two immediates aren't
/// independent.
static SDValue tryCombineToEXTR(SDNode *N,
TargetLowering::DAGCombinerInfo &DCI) {
SelectionDAG &DAG = DCI.DAG;
SDLoc DL(N);
EVT VT = N->getValueType(0);
assert(N->getOpcode() == ISD::OR && "Unexpected root");
if (VT != MVT::i32 && VT != MVT::i64)
return SDValue();
SDValue LHS;
uint32_t ShiftLHS = 0;
bool LHSFromHi = 0;
if (!findEXTRHalf(N->getOperand(0), LHS, ShiftLHS, LHSFromHi))
return SDValue();
SDValue RHS;
uint32_t ShiftRHS = 0;
bool RHSFromHi = 0;
if (!findEXTRHalf(N->getOperand(1), RHS, ShiftRHS, RHSFromHi))
return SDValue();
// If they're both trying to come from the high part of the register, they're
// not really an EXTR.
if (LHSFromHi == RHSFromHi)
return SDValue();
if (ShiftLHS + ShiftRHS != VT.getSizeInBits())
return SDValue();
if (LHSFromHi) {
std::swap(LHS, RHS);
std::swap(ShiftLHS, ShiftRHS);
}
return DAG.getNode(AArch64ISD::EXTR, DL, VT,
LHS, RHS,
DAG.getConstant(ShiftRHS, MVT::i64));
}
/// Target-specific dag combine xforms for ISD::OR
static SDValue PerformORCombine(SDNode *N,
TargetLowering::DAGCombinerInfo &DCI,
const AArch64Subtarget *Subtarget) {
SelectionDAG &DAG = DCI.DAG;
EVT VT = N->getValueType(0);
if(!DAG.getTargetLoweringInfo().isTypeLegal(VT))
return SDValue();
// Attempt to recognise bitfield-insert operations.
SDValue Res = tryCombineToBFI(N, DCI, Subtarget);
if (Res.getNode())
return Res;
// Attempt to combine an existing MaskedBFI operation into one with a larger
// mask.
Res = tryCombineToLargerBFI(N, DCI, Subtarget);
if (Res.getNode())
return Res;
Res = tryCombineToEXTR(N, DCI);
if (Res.getNode())
return Res;
return SDValue();
}
/// Target-specific dag combine xforms for ISD::SRA
static SDValue PerformSRACombine(SDNode *N,
TargetLowering::DAGCombinerInfo &DCI) {
SelectionDAG &DAG = DCI.DAG;
SDLoc DL(N);
EVT VT = N->getValueType(0);
// We're looking for an SRA/SHL pair which form an SBFX.
if (VT != MVT::i32 && VT != MVT::i64)
return SDValue();
if (!isa<ConstantSDNode>(N->getOperand(1)))
return SDValue();
uint64_t ExtraSignBits = N->getConstantOperandVal(1);
SDValue Shift = N->getOperand(0);
if (Shift.getOpcode() != ISD::SHL)
return SDValue();
if (!isa<ConstantSDNode>(Shift->getOperand(1)))
return SDValue();
uint64_t BitsOnLeft = Shift->getConstantOperandVal(1);
uint64_t Width = VT.getSizeInBits() - ExtraSignBits;
uint64_t LSB = VT.getSizeInBits() - Width - BitsOnLeft;
if (LSB > VT.getSizeInBits() || Width > VT.getSizeInBits())
return SDValue();
return DAG.getNode(AArch64ISD::SBFX, DL, VT, Shift.getOperand(0),
DAG.getConstant(LSB, MVT::i64),
DAG.getConstant(LSB + Width - 1, MVT::i64));
}
SDValue
AArch64TargetLowering::PerformDAGCombine(SDNode *N,
DAGCombinerInfo &DCI) const {
switch (N->getOpcode()) {
default: break;
case ISD::AND: return PerformANDCombine(N, DCI);
case ISD::OR: return PerformORCombine(N, DCI, getSubtarget());
case ISD::SRA: return PerformSRACombine(N, DCI);
}
return SDValue();
}
bool
AArch64TargetLowering::isFMAFasterThanFMulAndFAdd(EVT VT) const {
VT = VT.getScalarType();
if (!VT.isSimple())
return false;
switch (VT.getSimpleVT().SimpleTy) {
case MVT::f16:
case MVT::f32:
case MVT::f64:
return true;
case MVT::f128:
return false;
default:
break;
}
return false;
}
AArch64TargetLowering::ConstraintType
AArch64TargetLowering::getConstraintType(const std::string &Constraint) const {
if (Constraint.size() == 1) {
switch (Constraint[0]) {
default: break;
case 'w': // An FP/SIMD vector register
return C_RegisterClass;
case 'I': // Constant that can be used with an ADD instruction
case 'J': // Constant that can be used with a SUB instruction
case 'K': // Constant that can be used with a 32-bit logical instruction
case 'L': // Constant that can be used with a 64-bit logical instruction
case 'M': // Constant that can be used as a 32-bit MOV immediate
case 'N': // Constant that can be used as a 64-bit MOV immediate
case 'Y': // Floating point constant zero
case 'Z': // Integer constant zero
return C_Other;
case 'Q': // A memory reference with base register and no offset
return C_Memory;
case 'S': // A symbolic address
return C_Other;
}
}
// FIXME: Ump, Utf, Usa, Ush
// Ump: A memory address suitable for ldp/stp in SI, DI, SF and DF modes,
// whatever they may be
// Utf: A memory address suitable for ldp/stp in TF mode, whatever it may be
// Usa: An absolute symbolic address
// Ush: The high part (bits 32:12) of a pc-relative symbolic address
assert(Constraint != "Ump" && Constraint != "Utf" && Constraint != "Usa"
&& Constraint != "Ush" && "Unimplemented constraints");
return TargetLowering::getConstraintType(Constraint);
}
TargetLowering::ConstraintWeight
AArch64TargetLowering::getSingleConstraintMatchWeight(AsmOperandInfo &Info,
const char *Constraint) const {
llvm_unreachable("Constraint weight unimplemented");
}
void
AArch64TargetLowering::LowerAsmOperandForConstraint(SDValue Op,
std::string &Constraint,
std::vector<SDValue> &Ops,
SelectionDAG &DAG) const {
SDValue Result(0, 0);
// Only length 1 constraints are C_Other.
if (Constraint.size() != 1) return;
// Only C_Other constraints get lowered like this. That means constants for us
// so return early if there's no hope the constraint can be lowered.
switch(Constraint[0]) {
default: break;
case 'I': case 'J': case 'K': case 'L':
case 'M': case 'N': case 'Z': {
ConstantSDNode *C = dyn_cast<ConstantSDNode>(Op);
if (!C)
return;
uint64_t CVal = C->getZExtValue();
uint32_t Bits;
switch (Constraint[0]) {
default:
// FIXME: 'M' and 'N' are MOV pseudo-insts -- unsupported in assembly. 'J'
// is a peculiarly useless SUB constraint.
llvm_unreachable("Unimplemented C_Other constraint");
case 'I':
if (CVal <= 0xfff)
break;
return;
case 'K':
if (A64Imms::isLogicalImm(32, CVal, Bits))
break;
return;
case 'L':
if (A64Imms::isLogicalImm(64, CVal, Bits))
break;
return;
case 'Z':
if (CVal == 0)
break;
return;
}
Result = DAG.getTargetConstant(CVal, Op.getValueType());
break;
}
case 'S': {
// An absolute symbolic address or label reference.
if (const GlobalAddressSDNode *GA = dyn_cast<GlobalAddressSDNode>(Op)) {
Result = DAG.getTargetGlobalAddress(GA->getGlobal(), SDLoc(Op),
GA->getValueType(0));
} else if (const BlockAddressSDNode *BA
= dyn_cast<BlockAddressSDNode>(Op)) {
Result = DAG.getTargetBlockAddress(BA->getBlockAddress(),
BA->getValueType(0));
} else if (const ExternalSymbolSDNode *ES
= dyn_cast<ExternalSymbolSDNode>(Op)) {
Result = DAG.getTargetExternalSymbol(ES->getSymbol(),
ES->getValueType(0));
} else
return;
break;
}
case 'Y':
if (const ConstantFPSDNode *CFP = dyn_cast<ConstantFPSDNode>(Op)) {
if (CFP->isExactlyValue(0.0)) {
Result = DAG.getTargetConstantFP(0.0, CFP->getValueType(0));
break;
}
}
return;
}
if (Result.getNode()) {
Ops.push_back(Result);
return;
}
// It's an unknown constraint for us. Let generic code have a go.
TargetLowering::LowerAsmOperandForConstraint(Op, Constraint, Ops, DAG);
}
std::pair<unsigned, const TargetRegisterClass*>
AArch64TargetLowering::getRegForInlineAsmConstraint(
const std::string &Constraint,
MVT VT) const {
if (Constraint.size() == 1) {
switch (Constraint[0]) {
case 'r':
if (VT.getSizeInBits() <= 32)
return std::make_pair(0U, &AArch64::GPR32RegClass);
else if (VT == MVT::i64)
return std::make_pair(0U, &AArch64::GPR64RegClass);
break;
case 'w':
if (VT == MVT::f16)
return std::make_pair(0U, &AArch64::FPR16RegClass);
else if (VT == MVT::f32)
return std::make_pair(0U, &AArch64::FPR32RegClass);
else if (VT == MVT::f64)
return std::make_pair(0U, &AArch64::FPR64RegClass);
else if (VT.getSizeInBits() == 64)
return std::make_pair(0U, &AArch64::VPR64RegClass);
else if (VT == MVT::f128)
return std::make_pair(0U, &AArch64::FPR128RegClass);
else if (VT.getSizeInBits() == 128)
return std::make_pair(0U, &AArch64::VPR128RegClass);
break;
}
}
// Use the default implementation in TargetLowering to convert the register
// constraint into a member of a register class.
return TargetLowering::getRegForInlineAsmConstraint(Constraint, VT);
}