llvm-project/llvm/lib/Target/XCore/XCoreISelLowering.cpp

1940 lines
75 KiB
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//===-- XCoreISelLowering.cpp - XCore DAG Lowering Implementation ---------===//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
//
// This file implements the XCoreTargetLowering class.
//
//===----------------------------------------------------------------------===//
#include "XCoreISelLowering.h"
#include "XCore.h"
#include "XCoreMachineFunctionInfo.h"
#include "XCoreSubtarget.h"
#include "XCoreTargetMachine.h"
#include "XCoreTargetObjectFile.h"
#include "llvm/CodeGen/CallingConvLower.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineJumpTableInfo.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/ValueTypes.h"
#include "llvm/IR/CallingConv.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/GlobalAlias.h"
#include "llvm/IR/GlobalVariable.h"
#include "llvm/IR/Intrinsics.h"
#include "llvm/IR/IntrinsicsXCore.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/KnownBits.h"
#include "llvm/Support/raw_ostream.h"
#include <algorithm>
using namespace llvm;
#define DEBUG_TYPE "xcore-lower"
const char *XCoreTargetLowering::
getTargetNodeName(unsigned Opcode) const
{
switch ((XCoreISD::NodeType)Opcode)
{
case XCoreISD::FIRST_NUMBER : break;
case XCoreISD::BL : return "XCoreISD::BL";
case XCoreISD::PCRelativeWrapper : return "XCoreISD::PCRelativeWrapper";
case XCoreISD::DPRelativeWrapper : return "XCoreISD::DPRelativeWrapper";
case XCoreISD::CPRelativeWrapper : return "XCoreISD::CPRelativeWrapper";
case XCoreISD::LDWSP : return "XCoreISD::LDWSP";
case XCoreISD::STWSP : return "XCoreISD::STWSP";
case XCoreISD::RETSP : return "XCoreISD::RETSP";
case XCoreISD::LADD : return "XCoreISD::LADD";
case XCoreISD::LSUB : return "XCoreISD::LSUB";
case XCoreISD::LMUL : return "XCoreISD::LMUL";
case XCoreISD::MACCU : return "XCoreISD::MACCU";
case XCoreISD::MACCS : return "XCoreISD::MACCS";
case XCoreISD::CRC8 : return "XCoreISD::CRC8";
case XCoreISD::BR_JT : return "XCoreISD::BR_JT";
case XCoreISD::BR_JT32 : return "XCoreISD::BR_JT32";
case XCoreISD::FRAME_TO_ARGS_OFFSET : return "XCoreISD::FRAME_TO_ARGS_OFFSET";
case XCoreISD::EH_RETURN : return "XCoreISD::EH_RETURN";
case XCoreISD::MEMBARRIER : return "XCoreISD::MEMBARRIER";
}
return nullptr;
}
XCoreTargetLowering::XCoreTargetLowering(const TargetMachine &TM,
const XCoreSubtarget &Subtarget)
: TargetLowering(TM), TM(TM), Subtarget(Subtarget) {
// Set up the register classes.
addRegisterClass(MVT::i32, &XCore::GRRegsRegClass);
// Compute derived properties from the register classes
computeRegisterProperties(Subtarget.getRegisterInfo());
setStackPointerRegisterToSaveRestore(XCore::SP);
setSchedulingPreference(Sched::Source);
// Use i32 for setcc operations results (slt, sgt, ...).
setBooleanContents(ZeroOrOneBooleanContent);
setBooleanVectorContents(ZeroOrOneBooleanContent); // FIXME: Is this correct?
// XCore does not have the NodeTypes below.
setOperationAction(ISD::BR_CC, MVT::i32, Expand);
setOperationAction(ISD::SELECT_CC, MVT::i32, Expand);
// 64bit
setOperationAction(ISD::ADD, MVT::i64, Custom);
setOperationAction(ISD::SUB, MVT::i64, Custom);
setOperationAction(ISD::SMUL_LOHI, MVT::i32, Custom);
setOperationAction(ISD::UMUL_LOHI, MVT::i32, Custom);
setOperationAction(ISD::MULHS, MVT::i32, Expand);
setOperationAction(ISD::MULHU, MVT::i32, Expand);
setOperationAction(ISD::SHL_PARTS, MVT::i32, Expand);
setOperationAction(ISD::SRA_PARTS, MVT::i32, Expand);
setOperationAction(ISD::SRL_PARTS, MVT::i32, Expand);
// Bit Manipulation
setOperationAction(ISD::CTPOP, MVT::i32, Expand);
setOperationAction(ISD::ROTL , MVT::i32, Expand);
setOperationAction(ISD::ROTR , MVT::i32, Expand);
setOperationAction(ISD::BITREVERSE , MVT::i32, Legal);
setOperationAction(ISD::TRAP, MVT::Other, Legal);
// Jump tables.
setOperationAction(ISD::BR_JT, MVT::Other, Custom);
setOperationAction(ISD::GlobalAddress, MVT::i32, Custom);
setOperationAction(ISD::BlockAddress, MVT::i32 , Custom);
// Conversion of i64 -> double produces constantpool nodes
setOperationAction(ISD::ConstantPool, MVT::i32, Custom);
// Loads
for (MVT VT : MVT::integer_valuetypes()) {
setLoadExtAction(ISD::EXTLOAD, VT, MVT::i1, Promote);
setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i1, Promote);
setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i1, Promote);
setLoadExtAction(ISD::SEXTLOAD, VT, MVT::i8, Expand);
setLoadExtAction(ISD::ZEXTLOAD, VT, MVT::i16, Expand);
}
// Custom expand misaligned loads / stores.
setOperationAction(ISD::LOAD, MVT::i32, Custom);
setOperationAction(ISD::STORE, MVT::i32, Custom);
// Varargs
setOperationAction(ISD::VAEND, MVT::Other, Expand);
setOperationAction(ISD::VACOPY, MVT::Other, Expand);
setOperationAction(ISD::VAARG, MVT::Other, Custom);
setOperationAction(ISD::VASTART, MVT::Other, Custom);
// Dynamic stack
setOperationAction(ISD::STACKSAVE, MVT::Other, Expand);
setOperationAction(ISD::STACKRESTORE, MVT::Other, Expand);
setOperationAction(ISD::DYNAMIC_STACKALLOC, MVT::i32, Expand);
// Exception handling
setOperationAction(ISD::EH_RETURN, MVT::Other, Custom);
setOperationAction(ISD::FRAME_TO_ARGS_OFFSET, MVT::i32, Custom);
// Atomic operations
// We request a fence for ATOMIC_* instructions, to reduce them to Monotonic.
// As we are always Sequential Consistent, an ATOMIC_FENCE becomes a no OP.
setOperationAction(ISD::ATOMIC_FENCE, MVT::Other, Custom);
setOperationAction(ISD::ATOMIC_LOAD, MVT::i32, Custom);
setOperationAction(ISD::ATOMIC_STORE, MVT::i32, Custom);
// TRAMPOLINE is custom lowered.
setOperationAction(ISD::INIT_TRAMPOLINE, MVT::Other, Custom);
setOperationAction(ISD::ADJUST_TRAMPOLINE, MVT::Other, Custom);
// We want to custom lower some of our intrinsics.
setOperationAction(ISD::INTRINSIC_WO_CHAIN, MVT::Other, Custom);
MaxStoresPerMemset = MaxStoresPerMemsetOptSize = 4;
MaxStoresPerMemmove = MaxStoresPerMemmoveOptSize
= MaxStoresPerMemcpy = MaxStoresPerMemcpyOptSize = 2;
// We have target-specific dag combine patterns for the following nodes:
setTargetDAGCombine(ISD::STORE);
setTargetDAGCombine(ISD::ADD);
setTargetDAGCombine(ISD::INTRINSIC_VOID);
setTargetDAGCombine(ISD::INTRINSIC_W_CHAIN);
setMinFunctionAlignment(Align(2));
setPrefFunctionAlignment(Align(4));
}
bool XCoreTargetLowering::isZExtFree(SDValue Val, EVT VT2) const {
if (Val.getOpcode() != ISD::LOAD)
return false;
EVT VT1 = Val.getValueType();
if (!VT1.isSimple() || !VT1.isInteger() ||
!VT2.isSimple() || !VT2.isInteger())
return false;
switch (VT1.getSimpleVT().SimpleTy) {
default: break;
case MVT::i8:
return true;
}
return false;
}
SDValue XCoreTargetLowering::
LowerOperation(SDValue Op, SelectionDAG &DAG) const {
switch (Op.getOpcode())
{
case ISD::EH_RETURN: return LowerEH_RETURN(Op, DAG);
case ISD::GlobalAddress: return LowerGlobalAddress(Op, DAG);
case ISD::BlockAddress: return LowerBlockAddress(Op, DAG);
case ISD::ConstantPool: return LowerConstantPool(Op, DAG);
case ISD::BR_JT: return LowerBR_JT(Op, DAG);
case ISD::LOAD: return LowerLOAD(Op, DAG);
case ISD::STORE: return LowerSTORE(Op, DAG);
case ISD::VAARG: return LowerVAARG(Op, DAG);
case ISD::VASTART: return LowerVASTART(Op, DAG);
case ISD::SMUL_LOHI: return LowerSMUL_LOHI(Op, DAG);
case ISD::UMUL_LOHI: return LowerUMUL_LOHI(Op, DAG);
// FIXME: Remove these when LegalizeDAGTypes lands.
case ISD::ADD:
case ISD::SUB: return ExpandADDSUB(Op.getNode(), DAG);
case ISD::FRAMEADDR: return LowerFRAMEADDR(Op, DAG);
case ISD::RETURNADDR: return LowerRETURNADDR(Op, DAG);
case ISD::FRAME_TO_ARGS_OFFSET: return LowerFRAME_TO_ARGS_OFFSET(Op, DAG);
case ISD::INIT_TRAMPOLINE: return LowerINIT_TRAMPOLINE(Op, DAG);
case ISD::ADJUST_TRAMPOLINE: return LowerADJUST_TRAMPOLINE(Op, DAG);
case ISD::INTRINSIC_WO_CHAIN: return LowerINTRINSIC_WO_CHAIN(Op, DAG);
case ISD::ATOMIC_FENCE: return LowerATOMIC_FENCE(Op, DAG);
case ISD::ATOMIC_LOAD: return LowerATOMIC_LOAD(Op, DAG);
case ISD::ATOMIC_STORE: return LowerATOMIC_STORE(Op, DAG);
default:
llvm_unreachable("unimplemented operand");
}
}
/// ReplaceNodeResults - Replace the results of node with an illegal result
/// type with new values built out of custom code.
void XCoreTargetLowering::ReplaceNodeResults(SDNode *N,
SmallVectorImpl<SDValue>&Results,
SelectionDAG &DAG) const {
switch (N->getOpcode()) {
default:
llvm_unreachable("Don't know how to custom expand this!");
case ISD::ADD:
case ISD::SUB:
Results.push_back(ExpandADDSUB(N, DAG));
return;
}
}
//===----------------------------------------------------------------------===//
// Misc Lower Operation implementation
//===----------------------------------------------------------------------===//
SDValue XCoreTargetLowering::getGlobalAddressWrapper(SDValue GA,
const GlobalValue *GV,
SelectionDAG &DAG) const {
// FIXME there is no actual debug info here
SDLoc dl(GA);
if (GV->getValueType()->isFunctionTy())
return DAG.getNode(XCoreISD::PCRelativeWrapper, dl, MVT::i32, GA);
const auto *GVar = dyn_cast<GlobalVariable>(GV);
if ((GV->hasSection() && GV->getSection().startswith(".cp.")) ||
(GVar && GVar->isConstant() && GV->hasLocalLinkage()))
return DAG.getNode(XCoreISD::CPRelativeWrapper, dl, MVT::i32, GA);
return DAG.getNode(XCoreISD::DPRelativeWrapper, dl, MVT::i32, GA);
}
static bool IsSmallObject(const GlobalValue *GV, const XCoreTargetLowering &XTL) {
if (XTL.getTargetMachine().getCodeModel() == CodeModel::Small)
return true;
Type *ObjType = GV->getValueType();
if (!ObjType->isSized())
return false;
auto &DL = GV->getParent()->getDataLayout();
unsigned ObjSize = DL.getTypeAllocSize(ObjType);
return ObjSize < CodeModelLargeSize && ObjSize != 0;
}
SDValue XCoreTargetLowering::
LowerGlobalAddress(SDValue Op, SelectionDAG &DAG) const
{
const GlobalAddressSDNode *GN = cast<GlobalAddressSDNode>(Op);
const GlobalValue *GV = GN->getGlobal();
SDLoc DL(GN);
int64_t Offset = GN->getOffset();
if (IsSmallObject(GV, *this)) {
// We can only fold positive offsets that are a multiple of the word size.
int64_t FoldedOffset = std::max(Offset & ~3, (int64_t)0);
SDValue GA = DAG.getTargetGlobalAddress(GV, DL, MVT::i32, FoldedOffset);
GA = getGlobalAddressWrapper(GA, GV, DAG);
// Handle the rest of the offset.
if (Offset != FoldedOffset) {
SDValue Remaining = DAG.getConstant(Offset - FoldedOffset, DL, MVT::i32);
GA = DAG.getNode(ISD::ADD, DL, MVT::i32, GA, Remaining);
}
return GA;
} else {
// Ideally we would not fold in offset with an index <= 11.
Type *Ty = Type::getInt8PtrTy(*DAG.getContext());
Constant *GA = ConstantExpr::getBitCast(const_cast<GlobalValue*>(GV), Ty);
Ty = Type::getInt32Ty(*DAG.getContext());
Constant *Idx = ConstantInt::get(Ty, Offset);
Constant *GAI = ConstantExpr::getGetElementPtr(
Type::getInt8Ty(*DAG.getContext()), GA, Idx);
SDValue CP = DAG.getConstantPool(GAI, MVT::i32);
return DAG.getLoad(getPointerTy(DAG.getDataLayout()), DL,
DAG.getEntryNode(), CP, MachinePointerInfo());
}
}
SDValue XCoreTargetLowering::
LowerBlockAddress(SDValue Op, SelectionDAG &DAG) const
{
SDLoc DL(Op);
auto PtrVT = getPointerTy(DAG.getDataLayout());
const BlockAddress *BA = cast<BlockAddressSDNode>(Op)->getBlockAddress();
SDValue Result = DAG.getTargetBlockAddress(BA, PtrVT);
return DAG.getNode(XCoreISD::PCRelativeWrapper, DL, PtrVT, Result);
}
SDValue XCoreTargetLowering::
LowerConstantPool(SDValue Op, SelectionDAG &DAG) const
{
ConstantPoolSDNode *CP = cast<ConstantPoolSDNode>(Op);
// FIXME there isn't really debug info here
SDLoc dl(CP);
EVT PtrVT = Op.getValueType();
SDValue Res;
if (CP->isMachineConstantPoolEntry()) {
Res = DAG.getTargetConstantPool(CP->getMachineCPVal(), PtrVT,
CP->getAlign(), CP->getOffset());
} else {
Res = DAG.getTargetConstantPool(CP->getConstVal(), PtrVT, CP->getAlign(),
CP->getOffset());
}
return DAG.getNode(XCoreISD::CPRelativeWrapper, dl, MVT::i32, Res);
}
unsigned XCoreTargetLowering::getJumpTableEncoding() const {
return MachineJumpTableInfo::EK_Inline;
}
SDValue XCoreTargetLowering::
LowerBR_JT(SDValue Op, SelectionDAG &DAG) const
{
SDValue Chain = Op.getOperand(0);
SDValue Table = Op.getOperand(1);
SDValue Index = Op.getOperand(2);
SDLoc dl(Op);
JumpTableSDNode *JT = cast<JumpTableSDNode>(Table);
unsigned JTI = JT->getIndex();
MachineFunction &MF = DAG.getMachineFunction();
const MachineJumpTableInfo *MJTI = MF.getJumpTableInfo();
SDValue TargetJT = DAG.getTargetJumpTable(JT->getIndex(), MVT::i32);
unsigned NumEntries = MJTI->getJumpTables()[JTI].MBBs.size();
if (NumEntries <= 32) {
return DAG.getNode(XCoreISD::BR_JT, dl, MVT::Other, Chain, TargetJT, Index);
}
assert((NumEntries >> 31) == 0);
SDValue ScaledIndex = DAG.getNode(ISD::SHL, dl, MVT::i32, Index,
DAG.getConstant(1, dl, MVT::i32));
return DAG.getNode(XCoreISD::BR_JT32, dl, MVT::Other, Chain, TargetJT,
ScaledIndex);
}
SDValue XCoreTargetLowering::lowerLoadWordFromAlignedBasePlusOffset(
const SDLoc &DL, SDValue Chain, SDValue Base, int64_t Offset,
SelectionDAG &DAG) const {
auto PtrVT = getPointerTy(DAG.getDataLayout());
if ((Offset & 0x3) == 0) {
return DAG.getLoad(PtrVT, DL, Chain, Base, MachinePointerInfo());
}
// Lower to pair of consecutive word aligned loads plus some bit shifting.
int32_t HighOffset = alignTo(Offset, 4);
int32_t LowOffset = HighOffset - 4;
SDValue LowAddr, HighAddr;
if (GlobalAddressSDNode *GASD =
dyn_cast<GlobalAddressSDNode>(Base.getNode())) {
LowAddr = DAG.getGlobalAddress(GASD->getGlobal(), DL, Base.getValueType(),
LowOffset);
HighAddr = DAG.getGlobalAddress(GASD->getGlobal(), DL, Base.getValueType(),
HighOffset);
} else {
LowAddr = DAG.getNode(ISD::ADD, DL, MVT::i32, Base,
DAG.getConstant(LowOffset, DL, MVT::i32));
HighAddr = DAG.getNode(ISD::ADD, DL, MVT::i32, Base,
DAG.getConstant(HighOffset, DL, MVT::i32));
}
SDValue LowShift = DAG.getConstant((Offset - LowOffset) * 8, DL, MVT::i32);
SDValue HighShift = DAG.getConstant((HighOffset - Offset) * 8, DL, MVT::i32);
SDValue Low = DAG.getLoad(PtrVT, DL, Chain, LowAddr, MachinePointerInfo());
SDValue High = DAG.getLoad(PtrVT, DL, Chain, HighAddr, MachinePointerInfo());
SDValue LowShifted = DAG.getNode(ISD::SRL, DL, MVT::i32, Low, LowShift);
SDValue HighShifted = DAG.getNode(ISD::SHL, DL, MVT::i32, High, HighShift);
SDValue Result = DAG.getNode(ISD::OR, DL, MVT::i32, LowShifted, HighShifted);
Chain = DAG.getNode(ISD::TokenFactor, DL, MVT::Other, Low.getValue(1),
High.getValue(1));
SDValue Ops[] = { Result, Chain };
return DAG.getMergeValues(Ops, DL);
}
static bool isWordAligned(SDValue Value, SelectionDAG &DAG)
{
KnownBits Known = DAG.computeKnownBits(Value);
return Known.countMinTrailingZeros() >= 2;
}
SDValue XCoreTargetLowering::LowerLOAD(SDValue Op, SelectionDAG &DAG) const {
const TargetLowering &TLI = DAG.getTargetLoweringInfo();
LLVMContext &Context = *DAG.getContext();
LoadSDNode *LD = cast<LoadSDNode>(Op);
assert(LD->getExtensionType() == ISD::NON_EXTLOAD &&
"Unexpected extension type");
assert(LD->getMemoryVT() == MVT::i32 && "Unexpected load EVT");
if (allowsMemoryAccessForAlignment(Context, DAG.getDataLayout(),
LD->getMemoryVT(), *LD->getMemOperand()))
return SDValue();
SDValue Chain = LD->getChain();
SDValue BasePtr = LD->getBasePtr();
SDLoc DL(Op);
if (!LD->isVolatile()) {
const GlobalValue *GV;
int64_t Offset = 0;
if (DAG.isBaseWithConstantOffset(BasePtr) &&
isWordAligned(BasePtr->getOperand(0), DAG)) {
SDValue NewBasePtr = BasePtr->getOperand(0);
Offset = cast<ConstantSDNode>(BasePtr->getOperand(1))->getSExtValue();
return lowerLoadWordFromAlignedBasePlusOffset(DL, Chain, NewBasePtr,
Offset, DAG);
}
if (TLI.isGAPlusOffset(BasePtr.getNode(), GV, Offset) &&
GV->getPointerAlignment(DAG.getDataLayout()) >= 4) {
SDValue NewBasePtr = DAG.getGlobalAddress(GV, DL,
BasePtr->getValueType(0));
return lowerLoadWordFromAlignedBasePlusOffset(DL, Chain, NewBasePtr,
Offset, DAG);
}
}
if (LD->getAlignment() == 2) {
SDValue Low = DAG.getExtLoad(ISD::ZEXTLOAD, DL, MVT::i32, Chain, BasePtr,
LD->getPointerInfo(), MVT::i16, Align(2),
LD->getMemOperand()->getFlags());
SDValue HighAddr = DAG.getNode(ISD::ADD, DL, MVT::i32, BasePtr,
DAG.getConstant(2, DL, MVT::i32));
SDValue High =
DAG.getExtLoad(ISD::EXTLOAD, DL, MVT::i32, Chain, HighAddr,
LD->getPointerInfo().getWithOffset(2), MVT::i16,
Align(2), LD->getMemOperand()->getFlags());
SDValue HighShifted = DAG.getNode(ISD::SHL, DL, MVT::i32, High,
DAG.getConstant(16, DL, MVT::i32));
SDValue Result = DAG.getNode(ISD::OR, DL, MVT::i32, Low, HighShifted);
Chain = DAG.getNode(ISD::TokenFactor, DL, MVT::Other, Low.getValue(1),
High.getValue(1));
SDValue Ops[] = { Result, Chain };
return DAG.getMergeValues(Ops, DL);
}
// Lower to a call to __misaligned_load(BasePtr).
Type *IntPtrTy = DAG.getDataLayout().getIntPtrType(Context);
TargetLowering::ArgListTy Args;
TargetLowering::ArgListEntry Entry;
Entry.Ty = IntPtrTy;
Entry.Node = BasePtr;
Args.push_back(Entry);
TargetLowering::CallLoweringInfo CLI(DAG);
CLI.setDebugLoc(DL).setChain(Chain).setLibCallee(
CallingConv::C, IntPtrTy,
DAG.getExternalSymbol("__misaligned_load",
getPointerTy(DAG.getDataLayout())),
std::move(Args));
std::pair<SDValue, SDValue> CallResult = LowerCallTo(CLI);
SDValue Ops[] = { CallResult.first, CallResult.second };
return DAG.getMergeValues(Ops, DL);
}
SDValue XCoreTargetLowering::LowerSTORE(SDValue Op, SelectionDAG &DAG) const {
LLVMContext &Context = *DAG.getContext();
StoreSDNode *ST = cast<StoreSDNode>(Op);
assert(!ST->isTruncatingStore() && "Unexpected store type");
assert(ST->getMemoryVT() == MVT::i32 && "Unexpected store EVT");
if (allowsMemoryAccessForAlignment(Context, DAG.getDataLayout(),
ST->getMemoryVT(), *ST->getMemOperand()))
return SDValue();
SDValue Chain = ST->getChain();
SDValue BasePtr = ST->getBasePtr();
SDValue Value = ST->getValue();
SDLoc dl(Op);
if (ST->getAlignment() == 2) {
SDValue Low = Value;
SDValue High = DAG.getNode(ISD::SRL, dl, MVT::i32, Value,
DAG.getConstant(16, dl, MVT::i32));
SDValue StoreLow =
DAG.getTruncStore(Chain, dl, Low, BasePtr, ST->getPointerInfo(),
MVT::i16, Align(2), ST->getMemOperand()->getFlags());
SDValue HighAddr = DAG.getNode(ISD::ADD, dl, MVT::i32, BasePtr,
DAG.getConstant(2, dl, MVT::i32));
SDValue StoreHigh = DAG.getTruncStore(
Chain, dl, High, HighAddr, ST->getPointerInfo().getWithOffset(2),
MVT::i16, Align(2), ST->getMemOperand()->getFlags());
return DAG.getNode(ISD::TokenFactor, dl, MVT::Other, StoreLow, StoreHigh);
}
// Lower to a call to __misaligned_store(BasePtr, Value).
Type *IntPtrTy = DAG.getDataLayout().getIntPtrType(Context);
TargetLowering::ArgListTy Args;
TargetLowering::ArgListEntry Entry;
Entry.Ty = IntPtrTy;
Entry.Node = BasePtr;
Args.push_back(Entry);
Entry.Node = Value;
Args.push_back(Entry);
TargetLowering::CallLoweringInfo CLI(DAG);
CLI.setDebugLoc(dl).setChain(Chain).setCallee(
CallingConv::C, Type::getVoidTy(Context),
DAG.getExternalSymbol("__misaligned_store",
getPointerTy(DAG.getDataLayout())),
std::move(Args));
std::pair<SDValue, SDValue> CallResult = LowerCallTo(CLI);
return CallResult.second;
}
SDValue XCoreTargetLowering::
LowerSMUL_LOHI(SDValue Op, SelectionDAG &DAG) const
{
assert(Op.getValueType() == MVT::i32 && Op.getOpcode() == ISD::SMUL_LOHI &&
"Unexpected operand to lower!");
SDLoc dl(Op);
SDValue LHS = Op.getOperand(0);
SDValue RHS = Op.getOperand(1);
SDValue Zero = DAG.getConstant(0, dl, MVT::i32);
SDValue Hi = DAG.getNode(XCoreISD::MACCS, dl,
DAG.getVTList(MVT::i32, MVT::i32), Zero, Zero,
LHS, RHS);
SDValue Lo(Hi.getNode(), 1);
SDValue Ops[] = { Lo, Hi };
return DAG.getMergeValues(Ops, dl);
}
SDValue XCoreTargetLowering::
LowerUMUL_LOHI(SDValue Op, SelectionDAG &DAG) const
{
assert(Op.getValueType() == MVT::i32 && Op.getOpcode() == ISD::UMUL_LOHI &&
"Unexpected operand to lower!");
SDLoc dl(Op);
SDValue LHS = Op.getOperand(0);
SDValue RHS = Op.getOperand(1);
SDValue Zero = DAG.getConstant(0, dl, MVT::i32);
SDValue Hi = DAG.getNode(XCoreISD::LMUL, dl,
DAG.getVTList(MVT::i32, MVT::i32), LHS, RHS,
Zero, Zero);
SDValue Lo(Hi.getNode(), 1);
SDValue Ops[] = { Lo, Hi };
return DAG.getMergeValues(Ops, dl);
}
/// isADDADDMUL - Return whether Op is in a form that is equivalent to
/// add(add(mul(x,y),a),b). If requireIntermediatesHaveOneUse is true then
/// each intermediate result in the calculation must also have a single use.
/// If the Op is in the correct form the constituent parts are written to Mul0,
/// Mul1, Addend0 and Addend1.
static bool
isADDADDMUL(SDValue Op, SDValue &Mul0, SDValue &Mul1, SDValue &Addend0,
SDValue &Addend1, bool requireIntermediatesHaveOneUse)
{
if (Op.getOpcode() != ISD::ADD)
return false;
SDValue N0 = Op.getOperand(0);
SDValue N1 = Op.getOperand(1);
SDValue AddOp;
SDValue OtherOp;
if (N0.getOpcode() == ISD::ADD) {
AddOp = N0;
OtherOp = N1;
} else if (N1.getOpcode() == ISD::ADD) {
AddOp = N1;
OtherOp = N0;
} else {
return false;
}
if (requireIntermediatesHaveOneUse && !AddOp.hasOneUse())
return false;
if (OtherOp.getOpcode() == ISD::MUL) {
// add(add(a,b),mul(x,y))
if (requireIntermediatesHaveOneUse && !OtherOp.hasOneUse())
return false;
Mul0 = OtherOp.getOperand(0);
Mul1 = OtherOp.getOperand(1);
Addend0 = AddOp.getOperand(0);
Addend1 = AddOp.getOperand(1);
return true;
}
if (AddOp.getOperand(0).getOpcode() == ISD::MUL) {
// add(add(mul(x,y),a),b)
if (requireIntermediatesHaveOneUse && !AddOp.getOperand(0).hasOneUse())
return false;
Mul0 = AddOp.getOperand(0).getOperand(0);
Mul1 = AddOp.getOperand(0).getOperand(1);
Addend0 = AddOp.getOperand(1);
Addend1 = OtherOp;
return true;
}
if (AddOp.getOperand(1).getOpcode() == ISD::MUL) {
// add(add(a,mul(x,y)),b)
if (requireIntermediatesHaveOneUse && !AddOp.getOperand(1).hasOneUse())
return false;
Mul0 = AddOp.getOperand(1).getOperand(0);
Mul1 = AddOp.getOperand(1).getOperand(1);
Addend0 = AddOp.getOperand(0);
Addend1 = OtherOp;
return true;
}
return false;
}
SDValue XCoreTargetLowering::
TryExpandADDWithMul(SDNode *N, SelectionDAG &DAG) const
{
SDValue Mul;
SDValue Other;
if (N->getOperand(0).getOpcode() == ISD::MUL) {
Mul = N->getOperand(0);
Other = N->getOperand(1);
} else if (N->getOperand(1).getOpcode() == ISD::MUL) {
Mul = N->getOperand(1);
Other = N->getOperand(0);
} else {
return SDValue();
}
SDLoc dl(N);
SDValue LL, RL, AddendL, AddendH;
LL = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
Mul.getOperand(0), DAG.getConstant(0, dl, MVT::i32));
RL = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
Mul.getOperand(1), DAG.getConstant(0, dl, MVT::i32));
AddendL = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
Other, DAG.getConstant(0, dl, MVT::i32));
AddendH = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
Other, DAG.getConstant(1, dl, MVT::i32));
APInt HighMask = APInt::getHighBitsSet(64, 32);
unsigned LHSSB = DAG.ComputeNumSignBits(Mul.getOperand(0));
unsigned RHSSB = DAG.ComputeNumSignBits(Mul.getOperand(1));
if (DAG.MaskedValueIsZero(Mul.getOperand(0), HighMask) &&
DAG.MaskedValueIsZero(Mul.getOperand(1), HighMask)) {
// The inputs are both zero-extended.
SDValue Hi = DAG.getNode(XCoreISD::MACCU, dl,
DAG.getVTList(MVT::i32, MVT::i32), AddendH,
AddendL, LL, RL);
SDValue Lo(Hi.getNode(), 1);
return DAG.getNode(ISD::BUILD_PAIR, dl, MVT::i64, Lo, Hi);
}
if (LHSSB > 32 && RHSSB > 32) {
// The inputs are both sign-extended.
SDValue Hi = DAG.getNode(XCoreISD::MACCS, dl,
DAG.getVTList(MVT::i32, MVT::i32), AddendH,
AddendL, LL, RL);
SDValue Lo(Hi.getNode(), 1);
return DAG.getNode(ISD::BUILD_PAIR, dl, MVT::i64, Lo, Hi);
}
SDValue LH, RH;
LH = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
Mul.getOperand(0), DAG.getConstant(1, dl, MVT::i32));
RH = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
Mul.getOperand(1), DAG.getConstant(1, dl, MVT::i32));
SDValue Hi = DAG.getNode(XCoreISD::MACCU, dl,
DAG.getVTList(MVT::i32, MVT::i32), AddendH,
AddendL, LL, RL);
SDValue Lo(Hi.getNode(), 1);
RH = DAG.getNode(ISD::MUL, dl, MVT::i32, LL, RH);
LH = DAG.getNode(ISD::MUL, dl, MVT::i32, LH, RL);
Hi = DAG.getNode(ISD::ADD, dl, MVT::i32, Hi, RH);
Hi = DAG.getNode(ISD::ADD, dl, MVT::i32, Hi, LH);
return DAG.getNode(ISD::BUILD_PAIR, dl, MVT::i64, Lo, Hi);
}
SDValue XCoreTargetLowering::
ExpandADDSUB(SDNode *N, SelectionDAG &DAG) const
{
assert(N->getValueType(0) == MVT::i64 &&
(N->getOpcode() == ISD::ADD || N->getOpcode() == ISD::SUB) &&
"Unknown operand to lower!");
if (N->getOpcode() == ISD::ADD)
if (SDValue Result = TryExpandADDWithMul(N, DAG))
return Result;
SDLoc dl(N);
// Extract components
SDValue LHSL = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
N->getOperand(0),
DAG.getConstant(0, dl, MVT::i32));
SDValue LHSH = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
N->getOperand(0),
DAG.getConstant(1, dl, MVT::i32));
SDValue RHSL = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
N->getOperand(1),
DAG.getConstant(0, dl, MVT::i32));
SDValue RHSH = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
N->getOperand(1),
DAG.getConstant(1, dl, MVT::i32));
// Expand
unsigned Opcode = (N->getOpcode() == ISD::ADD) ? XCoreISD::LADD :
XCoreISD::LSUB;
SDValue Zero = DAG.getConstant(0, dl, MVT::i32);
SDValue Lo = DAG.getNode(Opcode, dl, DAG.getVTList(MVT::i32, MVT::i32),
LHSL, RHSL, Zero);
SDValue Carry(Lo.getNode(), 1);
SDValue Hi = DAG.getNode(Opcode, dl, DAG.getVTList(MVT::i32, MVT::i32),
LHSH, RHSH, Carry);
SDValue Ignored(Hi.getNode(), 1);
// Merge the pieces
return DAG.getNode(ISD::BUILD_PAIR, dl, MVT::i64, Lo, Hi);
}
SDValue XCoreTargetLowering::
LowerVAARG(SDValue Op, SelectionDAG &DAG) const
{
// Whist llvm does not support aggregate varargs we can ignore
// the possibility of the ValueType being an implicit byVal vararg.
SDNode *Node = Op.getNode();
EVT VT = Node->getValueType(0); // not an aggregate
SDValue InChain = Node->getOperand(0);
SDValue VAListPtr = Node->getOperand(1);
EVT PtrVT = VAListPtr.getValueType();
const Value *SV = cast<SrcValueSDNode>(Node->getOperand(2))->getValue();
SDLoc dl(Node);
SDValue VAList =
DAG.getLoad(PtrVT, dl, InChain, VAListPtr, MachinePointerInfo(SV));
// Increment the pointer, VAList, to the next vararg
SDValue nextPtr = DAG.getNode(ISD::ADD, dl, PtrVT, VAList,
DAG.getIntPtrConstant(VT.getSizeInBits() / 8,
dl));
// Store the incremented VAList to the legalized pointer
InChain = DAG.getStore(VAList.getValue(1), dl, nextPtr, VAListPtr,
MachinePointerInfo(SV));
// Load the actual argument out of the pointer VAList
return DAG.getLoad(VT, dl, InChain, VAList, MachinePointerInfo());
}
SDValue XCoreTargetLowering::
LowerVASTART(SDValue Op, SelectionDAG &DAG) const
{
SDLoc dl(Op);
// vastart stores the address of the VarArgsFrameIndex slot into the
// memory location argument
MachineFunction &MF = DAG.getMachineFunction();
XCoreFunctionInfo *XFI = MF.getInfo<XCoreFunctionInfo>();
SDValue Addr = DAG.getFrameIndex(XFI->getVarArgsFrameIndex(), MVT::i32);
return DAG.getStore(Op.getOperand(0), dl, Addr, Op.getOperand(1),
MachinePointerInfo());
}
SDValue XCoreTargetLowering::LowerFRAMEADDR(SDValue Op,
SelectionDAG &DAG) const {
// This nodes represent llvm.frameaddress on the DAG.
// It takes one operand, the index of the frame address to return.
// An index of zero corresponds to the current function's frame address.
// An index of one to the parent's frame address, and so on.
// Depths > 0 not supported yet!
if (cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue() > 0)
return SDValue();
MachineFunction &MF = DAG.getMachineFunction();
const TargetRegisterInfo *RegInfo = Subtarget.getRegisterInfo();
return DAG.getCopyFromReg(DAG.getEntryNode(), SDLoc(Op),
RegInfo->getFrameRegister(MF), MVT::i32);
}
SDValue XCoreTargetLowering::
LowerRETURNADDR(SDValue Op, SelectionDAG &DAG) const {
// This nodes represent llvm.returnaddress on the DAG.
// It takes one operand, the index of the return address to return.
// An index of zero corresponds to the current function's return address.
// An index of one to the parent's return address, and so on.
// Depths > 0 not supported yet!
if (cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue() > 0)
return SDValue();
MachineFunction &MF = DAG.getMachineFunction();
XCoreFunctionInfo *XFI = MF.getInfo<XCoreFunctionInfo>();
int FI = XFI->createLRSpillSlot(MF);
SDValue FIN = DAG.getFrameIndex(FI, MVT::i32);
return DAG.getLoad(getPointerTy(DAG.getDataLayout()), SDLoc(Op),
DAG.getEntryNode(), FIN,
MachinePointerInfo::getFixedStack(MF, FI));
}
SDValue XCoreTargetLowering::
LowerFRAME_TO_ARGS_OFFSET(SDValue Op, SelectionDAG &DAG) const {
// This node represents offset from frame pointer to first on-stack argument.
// This is needed for correct stack adjustment during unwind.
// However, we don't know the offset until after the frame has be finalised.
// This is done during the XCoreFTAOElim pass.
return DAG.getNode(XCoreISD::FRAME_TO_ARGS_OFFSET, SDLoc(Op), MVT::i32);
}
SDValue XCoreTargetLowering::
LowerEH_RETURN(SDValue Op, SelectionDAG &DAG) const {
// OUTCHAIN = EH_RETURN(INCHAIN, OFFSET, HANDLER)
// This node represents 'eh_return' gcc dwarf builtin, which is used to
// return from exception. The general meaning is: adjust stack by OFFSET and
// pass execution to HANDLER.
MachineFunction &MF = DAG.getMachineFunction();
SDValue Chain = Op.getOperand(0);
SDValue Offset = Op.getOperand(1);
SDValue Handler = Op.getOperand(2);
SDLoc dl(Op);
// Absolute SP = (FP + FrameToArgs) + Offset
const TargetRegisterInfo *RegInfo = Subtarget.getRegisterInfo();
SDValue Stack = DAG.getCopyFromReg(DAG.getEntryNode(), dl,
RegInfo->getFrameRegister(MF), MVT::i32);
SDValue FrameToArgs = DAG.getNode(XCoreISD::FRAME_TO_ARGS_OFFSET, dl,
MVT::i32);
Stack = DAG.getNode(ISD::ADD, dl, MVT::i32, Stack, FrameToArgs);
Stack = DAG.getNode(ISD::ADD, dl, MVT::i32, Stack, Offset);
// R0=ExceptionPointerRegister R1=ExceptionSelectorRegister
// which leaves 2 caller saved registers, R2 & R3 for us to use.
unsigned StackReg = XCore::R2;
unsigned HandlerReg = XCore::R3;
SDValue OutChains[] = {
DAG.getCopyToReg(Chain, dl, StackReg, Stack),
DAG.getCopyToReg(Chain, dl, HandlerReg, Handler)
};
Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, OutChains);
return DAG.getNode(XCoreISD::EH_RETURN, dl, MVT::Other, Chain,
DAG.getRegister(StackReg, MVT::i32),
DAG.getRegister(HandlerReg, MVT::i32));
}
SDValue XCoreTargetLowering::
LowerADJUST_TRAMPOLINE(SDValue Op, SelectionDAG &DAG) const {
return Op.getOperand(0);
}
SDValue XCoreTargetLowering::
LowerINIT_TRAMPOLINE(SDValue Op, SelectionDAG &DAG) const {
SDValue Chain = Op.getOperand(0);
SDValue Trmp = Op.getOperand(1); // trampoline
SDValue FPtr = Op.getOperand(2); // nested function
SDValue Nest = Op.getOperand(3); // 'nest' parameter value
const Value *TrmpAddr = cast<SrcValueSDNode>(Op.getOperand(4))->getValue();
// .align 4
// LDAPF_u10 r11, nest
// LDW_2rus r11, r11[0]
// STWSP_ru6 r11, sp[0]
// LDAPF_u10 r11, fptr
// LDW_2rus r11, r11[0]
// BAU_1r r11
// nest:
// .word nest
// fptr:
// .word fptr
SDValue OutChains[5];
SDValue Addr = Trmp;
SDLoc dl(Op);
OutChains[0] =
DAG.getStore(Chain, dl, DAG.getConstant(0x0a3cd805, dl, MVT::i32), Addr,
MachinePointerInfo(TrmpAddr));
Addr = DAG.getNode(ISD::ADD, dl, MVT::i32, Trmp,
DAG.getConstant(4, dl, MVT::i32));
OutChains[1] =
DAG.getStore(Chain, dl, DAG.getConstant(0xd80456c0, dl, MVT::i32), Addr,
MachinePointerInfo(TrmpAddr, 4));
Addr = DAG.getNode(ISD::ADD, dl, MVT::i32, Trmp,
DAG.getConstant(8, dl, MVT::i32));
OutChains[2] =
DAG.getStore(Chain, dl, DAG.getConstant(0x27fb0a3c, dl, MVT::i32), Addr,
MachinePointerInfo(TrmpAddr, 8));
Addr = DAG.getNode(ISD::ADD, dl, MVT::i32, Trmp,
DAG.getConstant(12, dl, MVT::i32));
OutChains[3] =
DAG.getStore(Chain, dl, Nest, Addr, MachinePointerInfo(TrmpAddr, 12));
Addr = DAG.getNode(ISD::ADD, dl, MVT::i32, Trmp,
DAG.getConstant(16, dl, MVT::i32));
OutChains[4] =
DAG.getStore(Chain, dl, FPtr, Addr, MachinePointerInfo(TrmpAddr, 16));
return DAG.getNode(ISD::TokenFactor, dl, MVT::Other, OutChains);
}
SDValue XCoreTargetLowering::
LowerINTRINSIC_WO_CHAIN(SDValue Op, SelectionDAG &DAG) const {
SDLoc DL(Op);
unsigned IntNo = cast<ConstantSDNode>(Op.getOperand(0))->getZExtValue();
switch (IntNo) {
case Intrinsic::xcore_crc8:
EVT VT = Op.getValueType();
SDValue Data =
DAG.getNode(XCoreISD::CRC8, DL, DAG.getVTList(VT, VT),
Op.getOperand(1), Op.getOperand(2) , Op.getOperand(3));
SDValue Crc(Data.getNode(), 1);
SDValue Results[] = { Crc, Data };
return DAG.getMergeValues(Results, DL);
}
return SDValue();
}
SDValue XCoreTargetLowering::
LowerATOMIC_FENCE(SDValue Op, SelectionDAG &DAG) const {
SDLoc DL(Op);
return DAG.getNode(XCoreISD::MEMBARRIER, DL, MVT::Other, Op.getOperand(0));
}
SDValue XCoreTargetLowering::
LowerATOMIC_LOAD(SDValue Op, SelectionDAG &DAG) const {
AtomicSDNode *N = cast<AtomicSDNode>(Op);
assert(N->getOpcode() == ISD::ATOMIC_LOAD && "Bad Atomic OP");
assert((N->getSuccessOrdering() == AtomicOrdering::Unordered ||
N->getSuccessOrdering() == AtomicOrdering::Monotonic) &&
"setInsertFencesForAtomic(true) expects unordered / monotonic");
if (N->getMemoryVT() == MVT::i32) {
if (N->getAlignment() < 4)
report_fatal_error("atomic load must be aligned");
return DAG.getLoad(getPointerTy(DAG.getDataLayout()), SDLoc(Op),
N->getChain(), N->getBasePtr(), N->getPointerInfo(),
N->getAlignment(), N->getMemOperand()->getFlags(),
N->getAAInfo(), N->getRanges());
}
if (N->getMemoryVT() == MVT::i16) {
if (N->getAlignment() < 2)
report_fatal_error("atomic load must be aligned");
return DAG.getExtLoad(ISD::EXTLOAD, SDLoc(Op), MVT::i32, N->getChain(),
N->getBasePtr(), N->getPointerInfo(), MVT::i16,
N->getAlignment(), N->getMemOperand()->getFlags(),
N->getAAInfo());
}
if (N->getMemoryVT() == MVT::i8)
return DAG.getExtLoad(ISD::EXTLOAD, SDLoc(Op), MVT::i32, N->getChain(),
N->getBasePtr(), N->getPointerInfo(), MVT::i8,
N->getAlignment(), N->getMemOperand()->getFlags(),
N->getAAInfo());
return SDValue();
}
SDValue XCoreTargetLowering::
LowerATOMIC_STORE(SDValue Op, SelectionDAG &DAG) const {
AtomicSDNode *N = cast<AtomicSDNode>(Op);
assert(N->getOpcode() == ISD::ATOMIC_STORE && "Bad Atomic OP");
assert((N->getSuccessOrdering() == AtomicOrdering::Unordered ||
N->getSuccessOrdering() == AtomicOrdering::Monotonic) &&
"setInsertFencesForAtomic(true) expects unordered / monotonic");
if (N->getMemoryVT() == MVT::i32) {
if (N->getAlignment() < 4)
report_fatal_error("atomic store must be aligned");
return DAG.getStore(N->getChain(), SDLoc(Op), N->getVal(), N->getBasePtr(),
N->getPointerInfo(), N->getAlignment(),
N->getMemOperand()->getFlags(), N->getAAInfo());
}
if (N->getMemoryVT() == MVT::i16) {
if (N->getAlignment() < 2)
report_fatal_error("atomic store must be aligned");
return DAG.getTruncStore(N->getChain(), SDLoc(Op), N->getVal(),
N->getBasePtr(), N->getPointerInfo(), MVT::i16,
N->getAlignment(), N->getMemOperand()->getFlags(),
N->getAAInfo());
}
if (N->getMemoryVT() == MVT::i8)
return DAG.getTruncStore(N->getChain(), SDLoc(Op), N->getVal(),
N->getBasePtr(), N->getPointerInfo(), MVT::i8,
N->getAlignment(), N->getMemOperand()->getFlags(),
N->getAAInfo());
return SDValue();
}
MachineMemOperand::Flags
XCoreTargetLowering::getTargetMMOFlags(const Instruction &I) const {
// Because of how we convert atomic_load and atomic_store to normal loads and
// stores in the DAG, we need to ensure that the MMOs are marked volatile
// since DAGCombine hasn't been updated to account for atomic, but non
// volatile loads. (See D57601)
if (auto *SI = dyn_cast<StoreInst>(&I))
if (SI->isAtomic())
return MachineMemOperand::MOVolatile;
if (auto *LI = dyn_cast<LoadInst>(&I))
if (LI->isAtomic())
return MachineMemOperand::MOVolatile;
if (auto *AI = dyn_cast<AtomicRMWInst>(&I))
if (AI->isAtomic())
return MachineMemOperand::MOVolatile;
if (auto *AI = dyn_cast<AtomicCmpXchgInst>(&I))
if (AI->isAtomic())
return MachineMemOperand::MOVolatile;
return MachineMemOperand::MONone;
}
//===----------------------------------------------------------------------===//
// Calling Convention Implementation
//===----------------------------------------------------------------------===//
#include "XCoreGenCallingConv.inc"
//===----------------------------------------------------------------------===//
// Call Calling Convention Implementation
//===----------------------------------------------------------------------===//
/// XCore call implementation
SDValue
XCoreTargetLowering::LowerCall(TargetLowering::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;
// XCore target does not yet support tail call optimization.
isTailCall = false;
// For now, only CallingConv::C implemented
switch (CallConv)
{
default:
report_fatal_error("Unsupported calling convention");
case CallingConv::Fast:
case CallingConv::C:
return LowerCCCCallTo(Chain, Callee, CallConv, isVarArg, isTailCall,
Outs, OutVals, Ins, dl, DAG, InVals);
}
}
/// LowerCallResult - Lower the result values of a call into the
/// appropriate copies out of appropriate physical registers / memory locations.
static SDValue LowerCallResult(SDValue Chain, SDValue InFlag,
const SmallVectorImpl<CCValAssign> &RVLocs,
const SDLoc &dl, SelectionDAG &DAG,
SmallVectorImpl<SDValue> &InVals) {
SmallVector<std::pair<int, unsigned>, 4> ResultMemLocs;
// Copy results out of physical registers.
for (unsigned i = 0, e = RVLocs.size(); i != e; ++i) {
const CCValAssign &VA = RVLocs[i];
if (VA.isRegLoc()) {
Chain = DAG.getCopyFromReg(Chain, dl, VA.getLocReg(), VA.getValVT(),
InFlag).getValue(1);
InFlag = Chain.getValue(2);
InVals.push_back(Chain.getValue(0));
} else {
assert(VA.isMemLoc());
ResultMemLocs.push_back(std::make_pair(VA.getLocMemOffset(),
InVals.size()));
// Reserve space for this result.
InVals.push_back(SDValue());
}
}
// Copy results out of memory.
SmallVector<SDValue, 4> MemOpChains;
for (unsigned i = 0, e = ResultMemLocs.size(); i != e; ++i) {
int offset = ResultMemLocs[i].first;
unsigned index = ResultMemLocs[i].second;
SDVTList VTs = DAG.getVTList(MVT::i32, MVT::Other);
SDValue Ops[] = { Chain, DAG.getConstant(offset / 4, dl, MVT::i32) };
SDValue load = DAG.getNode(XCoreISD::LDWSP, dl, VTs, Ops);
InVals[index] = load;
MemOpChains.push_back(load.getValue(1));
}
// Transform all loads nodes into one single node because
// all load nodes are independent of each other.
if (!MemOpChains.empty())
Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, MemOpChains);
return Chain;
}
/// LowerCCCCallTo - functions arguments are copied from virtual
/// regs to (physical regs)/(stack frame), CALLSEQ_START and
/// CALLSEQ_END are emitted.
/// TODO: isTailCall, sret.
SDValue XCoreTargetLowering::LowerCCCCallTo(
SDValue Chain, SDValue Callee, CallingConv::ID CallConv, bool isVarArg,
bool isTailCall, const SmallVectorImpl<ISD::OutputArg> &Outs,
const SmallVectorImpl<SDValue> &OutVals,
const SmallVectorImpl<ISD::InputArg> &Ins, const SDLoc &dl,
SelectionDAG &DAG, SmallVectorImpl<SDValue> &InVals) const {
// Analyze operands of the call, assigning locations to each operand.
SmallVector<CCValAssign, 16> ArgLocs;
CCState CCInfo(CallConv, isVarArg, DAG.getMachineFunction(), ArgLocs,
*DAG.getContext());
// The ABI dictates there should be one stack slot available to the callee
// on function entry (for saving lr).
CCInfo.AllocateStack(4, Align(4));
CCInfo.AnalyzeCallOperands(Outs, CC_XCore);
SmallVector<CCValAssign, 16> RVLocs;
// Analyze return values to determine the number of bytes of stack required.
CCState RetCCInfo(CallConv, isVarArg, DAG.getMachineFunction(), RVLocs,
*DAG.getContext());
RetCCInfo.AllocateStack(CCInfo.getNextStackOffset(), Align(4));
RetCCInfo.AnalyzeCallResult(Ins, RetCC_XCore);
// Get a count of how many bytes are to be pushed on the stack.
unsigned NumBytes = RetCCInfo.getNextStackOffset();
auto PtrVT = getPointerTy(DAG.getDataLayout());
Chain = DAG.getCALLSEQ_START(Chain, NumBytes, 0, dl);
SmallVector<std::pair<unsigned, SDValue>, 4> RegsToPass;
SmallVector<SDValue, 12> MemOpChains;
// Walk the register/memloc assignments, inserting copies/loads.
for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
CCValAssign &VA = ArgLocs[i];
SDValue Arg = OutVals[i];
// Promote the value if needed.
switch (VA.getLocInfo()) {
default: llvm_unreachable("Unknown loc info!");
case CCValAssign::Full: break;
case CCValAssign::SExt:
Arg = DAG.getNode(ISD::SIGN_EXTEND, dl, VA.getLocVT(), Arg);
break;
case CCValAssign::ZExt:
Arg = DAG.getNode(ISD::ZERO_EXTEND, dl, VA.getLocVT(), Arg);
break;
case CCValAssign::AExt:
Arg = DAG.getNode(ISD::ANY_EXTEND, dl, VA.getLocVT(), Arg);
break;
}
// Arguments that can be passed on register must be kept at
// RegsToPass vector
if (VA.isRegLoc()) {
RegsToPass.push_back(std::make_pair(VA.getLocReg(), Arg));
} else {
assert(VA.isMemLoc());
int Offset = VA.getLocMemOffset();
MemOpChains.push_back(DAG.getNode(XCoreISD::STWSP, dl, MVT::Other,
Chain, Arg,
DAG.getConstant(Offset/4, dl,
MVT::i32)));
}
}
// Transform all store nodes into one single node because
// all store nodes are independent of each other.
if (!MemOpChains.empty())
Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, MemOpChains);
// Build a sequence of copy-to-reg nodes chained together with token
// chain and flag operands which copy the outgoing args into registers.
// The InFlag in necessary since all emitted instructions must be
// stuck together.
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);
}
// If the callee is a GlobalAddress node (quite common, every direct call is)
// turn it into a TargetGlobalAddress node so that legalize doesn't hack it.
// Likewise ExternalSymbol -> TargetExternalSymbol.
if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(Callee))
Callee = DAG.getTargetGlobalAddress(G->getGlobal(), dl, MVT::i32);
else if (ExternalSymbolSDNode *E = dyn_cast<ExternalSymbolSDNode>(Callee))
Callee = DAG.getTargetExternalSymbol(E->getSymbol(), MVT::i32);
// XCoreBranchLink = #chain, #target_address, #opt_in_flags...
// = Chain, Callee, Reg#1, Reg#2, ...
//
// Returns a chain & a flag for retval copy to use.
SDVTList NodeTys = DAG.getVTList(MVT::Other, MVT::Glue);
SmallVector<SDValue, 8> Ops;
Ops.push_back(Chain);
Ops.push_back(Callee);
// Add argument registers to the end of the list so that they are
// known live into the call.
for (unsigned i = 0, e = RegsToPass.size(); i != e; ++i)
Ops.push_back(DAG.getRegister(RegsToPass[i].first,
RegsToPass[i].second.getValueType()));
if (InFlag.getNode())
Ops.push_back(InFlag);
Chain = DAG.getNode(XCoreISD::BL, dl, NodeTys, Ops);
InFlag = Chain.getValue(1);
// Create the CALLSEQ_END node.
Chain = DAG.getCALLSEQ_END(Chain, DAG.getConstant(NumBytes, dl, PtrVT, true),
DAG.getConstant(0, dl, PtrVT, true), InFlag, dl);
InFlag = Chain.getValue(1);
// Handle result values, copying them out of physregs into vregs that we
// return.
return LowerCallResult(Chain, InFlag, RVLocs, dl, DAG, InVals);
}
//===----------------------------------------------------------------------===//
// Formal Arguments Calling Convention Implementation
//===----------------------------------------------------------------------===//
namespace {
struct ArgDataPair { SDValue SDV; ISD::ArgFlagsTy Flags; };
}
/// XCore formal arguments implementation
SDValue XCoreTargetLowering::LowerFormalArguments(
SDValue Chain, CallingConv::ID CallConv, bool isVarArg,
const SmallVectorImpl<ISD::InputArg> &Ins, const SDLoc &dl,
SelectionDAG &DAG, SmallVectorImpl<SDValue> &InVals) const {
switch (CallConv)
{
default:
report_fatal_error("Unsupported calling convention");
case CallingConv::C:
case CallingConv::Fast:
return LowerCCCArguments(Chain, CallConv, isVarArg,
Ins, dl, DAG, InVals);
}
}
/// LowerCCCArguments - transform physical registers into
/// virtual registers and generate load operations for
/// arguments places on the stack.
/// TODO: sret
SDValue XCoreTargetLowering::LowerCCCArguments(
SDValue Chain, CallingConv::ID CallConv, bool isVarArg,
const SmallVectorImpl<ISD::InputArg> &Ins, const SDLoc &dl,
SelectionDAG &DAG, SmallVectorImpl<SDValue> &InVals) const {
MachineFunction &MF = DAG.getMachineFunction();
MachineFrameInfo &MFI = MF.getFrameInfo();
MachineRegisterInfo &RegInfo = MF.getRegInfo();
XCoreFunctionInfo *XFI = MF.getInfo<XCoreFunctionInfo>();
// Assign locations to all of the incoming arguments.
SmallVector<CCValAssign, 16> ArgLocs;
CCState CCInfo(CallConv, isVarArg, DAG.getMachineFunction(), ArgLocs,
*DAG.getContext());
CCInfo.AnalyzeFormalArguments(Ins, CC_XCore);
unsigned StackSlotSize = XCoreFrameLowering::stackSlotSize();
unsigned LRSaveSize = StackSlotSize;
if (!isVarArg)
XFI->setReturnStackOffset(CCInfo.getNextStackOffset() + LRSaveSize);
// All getCopyFromReg ops must precede any getMemcpys to prevent the
// scheduler clobbering a register before it has been copied.
// The stages are:
// 1. CopyFromReg (and load) arg & vararg registers.
// 2. Chain CopyFromReg nodes into a TokenFactor.
// 3. Memcpy 'byVal' args & push final InVals.
// 4. Chain mem ops nodes into a TokenFactor.
SmallVector<SDValue, 4> CFRegNode;
SmallVector<ArgDataPair, 4> ArgData;
SmallVector<SDValue, 4> MemOps;
// 1a. CopyFromReg (and load) arg registers.
for (unsigned i = 0, e = ArgLocs.size(); i != e; ++i) {
CCValAssign &VA = ArgLocs[i];
SDValue ArgIn;
if (VA.isRegLoc()) {
// Arguments passed in registers
EVT RegVT = VA.getLocVT();
switch (RegVT.getSimpleVT().SimpleTy) {
default:
{
#ifndef NDEBUG
errs() << "LowerFormalArguments Unhandled argument type: "
<< RegVT.getEVTString() << "\n";
#endif
llvm_unreachable(nullptr);
}
case MVT::i32:
Register VReg = RegInfo.createVirtualRegister(&XCore::GRRegsRegClass);
RegInfo.addLiveIn(VA.getLocReg(), VReg);
ArgIn = DAG.getCopyFromReg(Chain, dl, VReg, RegVT);
CFRegNode.push_back(ArgIn.getValue(ArgIn->getNumValues() - 1));
}
} else {
// sanity check
assert(VA.isMemLoc());
// Load the argument to a virtual register
unsigned ObjSize = VA.getLocVT().getSizeInBits()/8;
if (ObjSize > StackSlotSize) {
errs() << "LowerFormalArguments Unhandled argument type: "
<< EVT(VA.getLocVT()).getEVTString()
<< "\n";
}
// Create the frame index object for this incoming parameter...
int FI = MFI.CreateFixedObject(ObjSize,
LRSaveSize + VA.getLocMemOffset(),
true);
// Create the SelectionDAG nodes corresponding to a load
//from this parameter
SDValue FIN = DAG.getFrameIndex(FI, MVT::i32);
ArgIn = DAG.getLoad(VA.getLocVT(), dl, Chain, FIN,
MachinePointerInfo::getFixedStack(MF, FI));
}
const ArgDataPair ADP = { ArgIn, Ins[i].Flags };
ArgData.push_back(ADP);
}
// 1b. CopyFromReg vararg registers.
if (isVarArg) {
// Argument registers
static const MCPhysReg ArgRegs[] = {
XCore::R0, XCore::R1, XCore::R2, XCore::R3
};
XCoreFunctionInfo *XFI = MF.getInfo<XCoreFunctionInfo>();
unsigned FirstVAReg = CCInfo.getFirstUnallocated(ArgRegs);
if (FirstVAReg < array_lengthof(ArgRegs)) {
int offset = 0;
// Save remaining registers, storing higher register numbers at a higher
// address
for (int i = array_lengthof(ArgRegs) - 1; i >= (int)FirstVAReg; --i) {
// Create a stack slot
int FI = MFI.CreateFixedObject(4, offset, true);
if (i == (int)FirstVAReg) {
XFI->setVarArgsFrameIndex(FI);
}
offset -= StackSlotSize;
SDValue FIN = DAG.getFrameIndex(FI, MVT::i32);
// Move argument from phys reg -> virt reg
Register VReg = RegInfo.createVirtualRegister(&XCore::GRRegsRegClass);
RegInfo.addLiveIn(ArgRegs[i], VReg);
SDValue Val = DAG.getCopyFromReg(Chain, dl, VReg, MVT::i32);
CFRegNode.push_back(Val.getValue(Val->getNumValues() - 1));
// Move argument from virt reg -> stack
SDValue Store =
DAG.getStore(Val.getValue(1), dl, Val, FIN, MachinePointerInfo());
MemOps.push_back(Store);
}
} else {
// This will point to the next argument passed via stack.
XFI->setVarArgsFrameIndex(
MFI.CreateFixedObject(4, LRSaveSize + CCInfo.getNextStackOffset(),
true));
}
}
// 2. chain CopyFromReg nodes into a TokenFactor.
if (!CFRegNode.empty())
Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, CFRegNode);
// 3. Memcpy 'byVal' args & push final InVals.
// Aggregates passed "byVal" need to be copied by the callee.
// The callee will use a pointer to this copy, rather than the original
// pointer.
for (SmallVectorImpl<ArgDataPair>::const_iterator ArgDI = ArgData.begin(),
ArgDE = ArgData.end();
ArgDI != ArgDE; ++ArgDI) {
if (ArgDI->Flags.isByVal() && ArgDI->Flags.getByValSize()) {
unsigned Size = ArgDI->Flags.getByValSize();
Align Alignment =
std::max(Align(StackSlotSize), ArgDI->Flags.getNonZeroByValAlign());
// Create a new object on the stack and copy the pointee into it.
int FI = MFI.CreateStackObject(Size, Alignment, false);
SDValue FIN = DAG.getFrameIndex(FI, MVT::i32);
InVals.push_back(FIN);
MemOps.push_back(DAG.getMemcpy(
Chain, dl, FIN, ArgDI->SDV, DAG.getConstant(Size, dl, MVT::i32),
Alignment, false, false, false, MachinePointerInfo(),
MachinePointerInfo()));
} else {
InVals.push_back(ArgDI->SDV);
}
}
// 4, chain mem ops nodes into a TokenFactor.
if (!MemOps.empty()) {
MemOps.push_back(Chain);
Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, MemOps);
}
return Chain;
}
//===----------------------------------------------------------------------===//
// Return Value Calling Convention Implementation
//===----------------------------------------------------------------------===//
bool XCoreTargetLowering::
CanLowerReturn(CallingConv::ID CallConv, MachineFunction &MF,
bool isVarArg,
const SmallVectorImpl<ISD::OutputArg> &Outs,
LLVMContext &Context) const {
SmallVector<CCValAssign, 16> RVLocs;
CCState CCInfo(CallConv, isVarArg, MF, RVLocs, Context);
if (!CCInfo.CheckReturn(Outs, RetCC_XCore))
return false;
if (CCInfo.getNextStackOffset() != 0 && isVarArg)
return false;
return true;
}
SDValue
XCoreTargetLowering::LowerReturn(SDValue Chain, CallingConv::ID CallConv,
bool isVarArg,
const SmallVectorImpl<ISD::OutputArg> &Outs,
const SmallVectorImpl<SDValue> &OutVals,
const SDLoc &dl, SelectionDAG &DAG) const {
XCoreFunctionInfo *XFI =
DAG.getMachineFunction().getInfo<XCoreFunctionInfo>();
MachineFrameInfo &MFI = DAG.getMachineFunction().getFrameInfo();
// CCValAssign - represent the assignment of
// the return value to a location
SmallVector<CCValAssign, 16> RVLocs;
// CCState - Info about the registers and stack slot.
CCState CCInfo(CallConv, isVarArg, DAG.getMachineFunction(), RVLocs,
*DAG.getContext());
// Analyze return values.
if (!isVarArg)
CCInfo.AllocateStack(XFI->getReturnStackOffset(), Align(4));
CCInfo.AnalyzeReturn(Outs, RetCC_XCore);
SDValue Flag;
SmallVector<SDValue, 4> RetOps(1, Chain);
// Return on XCore is always a "retsp 0"
RetOps.push_back(DAG.getConstant(0, dl, MVT::i32));
SmallVector<SDValue, 4> MemOpChains;
// Handle return values that must be copied to memory.
for (unsigned i = 0, e = RVLocs.size(); i != e; ++i) {
CCValAssign &VA = RVLocs[i];
if (VA.isRegLoc())
continue;
assert(VA.isMemLoc());
if (isVarArg) {
report_fatal_error("Can't return value from vararg function in memory");
}
int Offset = VA.getLocMemOffset();
unsigned ObjSize = VA.getLocVT().getSizeInBits() / 8;
// Create the frame index object for the memory location.
int FI = MFI.CreateFixedObject(ObjSize, Offset, false);
// Create a SelectionDAG node corresponding to a store
// to this memory location.
SDValue FIN = DAG.getFrameIndex(FI, MVT::i32);
MemOpChains.push_back(DAG.getStore(
Chain, dl, OutVals[i], FIN,
MachinePointerInfo::getFixedStack(DAG.getMachineFunction(), FI)));
}
// Transform all store nodes into one single node because
// all stores are independent of each other.
if (!MemOpChains.empty())
Chain = DAG.getNode(ISD::TokenFactor, dl, MVT::Other, MemOpChains);
// Now handle return values copied to registers.
for (unsigned i = 0, e = RVLocs.size(); i != e; ++i) {
CCValAssign &VA = RVLocs[i];
if (!VA.isRegLoc())
continue;
// Copy the result values into the output registers.
Chain = DAG.getCopyToReg(Chain, dl, VA.getLocReg(), OutVals[i], Flag);
// guarantee that all emitted copies are
// stuck together, avoiding something bad
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(XCoreISD::RETSP, dl, MVT::Other, RetOps);
}
//===----------------------------------------------------------------------===//
// Other Lowering Code
//===----------------------------------------------------------------------===//
MachineBasicBlock *
XCoreTargetLowering::EmitInstrWithCustomInserter(MachineInstr &MI,
MachineBasicBlock *BB) const {
const TargetInstrInfo &TII = *Subtarget.getInstrInfo();
DebugLoc dl = MI.getDebugLoc();
assert((MI.getOpcode() == XCore::SELECT_CC) &&
"Unexpected instr type to insert");
// To "insert" a SELECT_CC instruction, we actually have to insert the diamond
// control-flow pattern. The incoming instruction knows the destination vreg
// to set, the condition code register to branch on, the true/false values to
// select between, and a branch opcode to use.
const BasicBlock *LLVM_BB = BB->getBasicBlock();
MachineFunction::iterator It = ++BB->getIterator();
// thisMBB:
// ...
// TrueVal = ...
// cmpTY ccX, r1, r2
// bCC copy1MBB
// fallthrough --> copy0MBB
MachineBasicBlock *thisMBB = BB;
MachineFunction *F = BB->getParent();
MachineBasicBlock *copy0MBB = F->CreateMachineBasicBlock(LLVM_BB);
MachineBasicBlock *sinkMBB = F->CreateMachineBasicBlock(LLVM_BB);
F->insert(It, copy0MBB);
F->insert(It, sinkMBB);
// Transfer the remainder of BB and its successor edges to sinkMBB.
sinkMBB->splice(sinkMBB->begin(), BB,
std::next(MachineBasicBlock::iterator(MI)), BB->end());
sinkMBB->transferSuccessorsAndUpdatePHIs(BB);
// Next, add the true and fallthrough blocks as its successors.
BB->addSuccessor(copy0MBB);
BB->addSuccessor(sinkMBB);
BuildMI(BB, dl, TII.get(XCore::BRFT_lru6))
.addReg(MI.getOperand(1).getReg())
.addMBB(sinkMBB);
// copy0MBB:
// %FalseValue = ...
// # fallthrough to sinkMBB
BB = copy0MBB;
// Update machine-CFG edges
BB->addSuccessor(sinkMBB);
// sinkMBB:
// %Result = phi [ %FalseValue, copy0MBB ], [ %TrueValue, thisMBB ]
// ...
BB = sinkMBB;
BuildMI(*BB, BB->begin(), dl, TII.get(XCore::PHI), MI.getOperand(0).getReg())
.addReg(MI.getOperand(3).getReg())
.addMBB(copy0MBB)
.addReg(MI.getOperand(2).getReg())
.addMBB(thisMBB);
MI.eraseFromParent(); // The pseudo instruction is gone now.
return BB;
}
//===----------------------------------------------------------------------===//
// Target Optimization Hooks
//===----------------------------------------------------------------------===//
SDValue XCoreTargetLowering::PerformDAGCombine(SDNode *N,
DAGCombinerInfo &DCI) const {
SelectionDAG &DAG = DCI.DAG;
SDLoc dl(N);
switch (N->getOpcode()) {
default: break;
case ISD::INTRINSIC_VOID:
switch (cast<ConstantSDNode>(N->getOperand(1))->getZExtValue()) {
case Intrinsic::xcore_outt:
case Intrinsic::xcore_outct:
case Intrinsic::xcore_chkct: {
SDValue OutVal = N->getOperand(3);
// These instructions ignore the high bits.
if (OutVal.hasOneUse()) {
unsigned BitWidth = OutVal.getValueSizeInBits();
APInt DemandedMask = APInt::getLowBitsSet(BitWidth, 8);
KnownBits Known;
TargetLowering::TargetLoweringOpt TLO(DAG, !DCI.isBeforeLegalize(),
!DCI.isBeforeLegalizeOps());
const TargetLowering &TLI = DAG.getTargetLoweringInfo();
if (TLI.ShrinkDemandedConstant(OutVal, DemandedMask, TLO) ||
TLI.SimplifyDemandedBits(OutVal, DemandedMask, Known, TLO))
DCI.CommitTargetLoweringOpt(TLO);
}
break;
}
case Intrinsic::xcore_setpt: {
SDValue Time = N->getOperand(3);
// This instruction ignores the high bits.
if (Time.hasOneUse()) {
unsigned BitWidth = Time.getValueSizeInBits();
APInt DemandedMask = APInt::getLowBitsSet(BitWidth, 16);
KnownBits Known;
TargetLowering::TargetLoweringOpt TLO(DAG, !DCI.isBeforeLegalize(),
!DCI.isBeforeLegalizeOps());
const TargetLowering &TLI = DAG.getTargetLoweringInfo();
if (TLI.ShrinkDemandedConstant(Time, DemandedMask, TLO) ||
TLI.SimplifyDemandedBits(Time, DemandedMask, Known, TLO))
DCI.CommitTargetLoweringOpt(TLO);
}
break;
}
}
break;
case XCoreISD::LADD: {
SDValue N0 = N->getOperand(0);
SDValue N1 = N->getOperand(1);
SDValue N2 = N->getOperand(2);
ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
EVT VT = N0.getValueType();
// canonicalize constant to RHS
if (N0C && !N1C)
return DAG.getNode(XCoreISD::LADD, dl, DAG.getVTList(VT, VT), N1, N0, N2);
// fold (ladd 0, 0, x) -> 0, x & 1
if (N0C && N0C->isNullValue() && N1C && N1C->isNullValue()) {
SDValue Carry = DAG.getConstant(0, dl, VT);
SDValue Result = DAG.getNode(ISD::AND, dl, VT, N2,
DAG.getConstant(1, dl, VT));
SDValue Ops[] = { Result, Carry };
return DAG.getMergeValues(Ops, dl);
}
// fold (ladd x, 0, y) -> 0, add x, y iff carry is unused and y has only the
// low bit set
if (N1C && N1C->isNullValue() && N->hasNUsesOfValue(0, 1)) {
APInt Mask = APInt::getHighBitsSet(VT.getSizeInBits(),
VT.getSizeInBits() - 1);
KnownBits Known = DAG.computeKnownBits(N2);
if ((Known.Zero & Mask) == Mask) {
SDValue Carry = DAG.getConstant(0, dl, VT);
SDValue Result = DAG.getNode(ISD::ADD, dl, VT, N0, N2);
SDValue Ops[] = { Result, Carry };
return DAG.getMergeValues(Ops, dl);
}
}
}
break;
case XCoreISD::LSUB: {
SDValue N0 = N->getOperand(0);
SDValue N1 = N->getOperand(1);
SDValue N2 = N->getOperand(2);
ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
EVT VT = N0.getValueType();
// fold (lsub 0, 0, x) -> x, -x iff x has only the low bit set
if (N0C && N0C->isNullValue() && N1C && N1C->isNullValue()) {
APInt Mask = APInt::getHighBitsSet(VT.getSizeInBits(),
VT.getSizeInBits() - 1);
KnownBits Known = DAG.computeKnownBits(N2);
if ((Known.Zero & Mask) == Mask) {
SDValue Borrow = N2;
SDValue Result = DAG.getNode(ISD::SUB, dl, VT,
DAG.getConstant(0, dl, VT), N2);
SDValue Ops[] = { Result, Borrow };
return DAG.getMergeValues(Ops, dl);
}
}
// fold (lsub x, 0, y) -> 0, sub x, y iff borrow is unused and y has only the
// low bit set
if (N1C && N1C->isNullValue() && N->hasNUsesOfValue(0, 1)) {
APInt Mask = APInt::getHighBitsSet(VT.getSizeInBits(),
VT.getSizeInBits() - 1);
KnownBits Known = DAG.computeKnownBits(N2);
if ((Known.Zero & Mask) == Mask) {
SDValue Borrow = DAG.getConstant(0, dl, VT);
SDValue Result = DAG.getNode(ISD::SUB, dl, VT, N0, N2);
SDValue Ops[] = { Result, Borrow };
return DAG.getMergeValues(Ops, dl);
}
}
}
break;
case XCoreISD::LMUL: {
SDValue N0 = N->getOperand(0);
SDValue N1 = N->getOperand(1);
SDValue N2 = N->getOperand(2);
SDValue N3 = N->getOperand(3);
ConstantSDNode *N0C = dyn_cast<ConstantSDNode>(N0);
ConstantSDNode *N1C = dyn_cast<ConstantSDNode>(N1);
EVT VT = N0.getValueType();
// Canonicalize multiplicative constant to RHS. If both multiplicative
// operands are constant canonicalize smallest to RHS.
if ((N0C && !N1C) ||
(N0C && N1C && N0C->getZExtValue() < N1C->getZExtValue()))
return DAG.getNode(XCoreISD::LMUL, dl, DAG.getVTList(VT, VT),
N1, N0, N2, N3);
// lmul(x, 0, a, b)
if (N1C && N1C->isNullValue()) {
// If the high result is unused fold to add(a, b)
if (N->hasNUsesOfValue(0, 0)) {
SDValue Lo = DAG.getNode(ISD::ADD, dl, VT, N2, N3);
SDValue Ops[] = { Lo, Lo };
return DAG.getMergeValues(Ops, dl);
}
// Otherwise fold to ladd(a, b, 0)
SDValue Result =
DAG.getNode(XCoreISD::LADD, dl, DAG.getVTList(VT, VT), N2, N3, N1);
SDValue Carry(Result.getNode(), 1);
SDValue Ops[] = { Carry, Result };
return DAG.getMergeValues(Ops, dl);
}
}
break;
case ISD::ADD: {
// Fold 32 bit expressions such as add(add(mul(x,y),a),b) ->
// lmul(x, y, a, b). The high result of lmul will be ignored.
// This is only profitable if the intermediate results are unused
// elsewhere.
SDValue Mul0, Mul1, Addend0, Addend1;
if (N->getValueType(0) == MVT::i32 &&
isADDADDMUL(SDValue(N, 0), Mul0, Mul1, Addend0, Addend1, true)) {
SDValue Ignored = DAG.getNode(XCoreISD::LMUL, dl,
DAG.getVTList(MVT::i32, MVT::i32), Mul0,
Mul1, Addend0, Addend1);
SDValue Result(Ignored.getNode(), 1);
return Result;
}
APInt HighMask = APInt::getHighBitsSet(64, 32);
// Fold 64 bit expression such as add(add(mul(x,y),a),b) ->
// lmul(x, y, a, b) if all operands are zero-extended. We do this
// before type legalization as it is messy to match the operands after
// that.
if (N->getValueType(0) == MVT::i64 &&
isADDADDMUL(SDValue(N, 0), Mul0, Mul1, Addend0, Addend1, false) &&
DAG.MaskedValueIsZero(Mul0, HighMask) &&
DAG.MaskedValueIsZero(Mul1, HighMask) &&
DAG.MaskedValueIsZero(Addend0, HighMask) &&
DAG.MaskedValueIsZero(Addend1, HighMask)) {
SDValue Mul0L = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
Mul0, DAG.getConstant(0, dl, MVT::i32));
SDValue Mul1L = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
Mul1, DAG.getConstant(0, dl, MVT::i32));
SDValue Addend0L = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
Addend0, DAG.getConstant(0, dl, MVT::i32));
SDValue Addend1L = DAG.getNode(ISD::EXTRACT_ELEMENT, dl, MVT::i32,
Addend1, DAG.getConstant(0, dl, MVT::i32));
SDValue Hi = DAG.getNode(XCoreISD::LMUL, dl,
DAG.getVTList(MVT::i32, MVT::i32), Mul0L, Mul1L,
Addend0L, Addend1L);
SDValue Lo(Hi.getNode(), 1);
return DAG.getNode(ISD::BUILD_PAIR, dl, MVT::i64, Lo, Hi);
}
}
break;
case ISD::STORE: {
// Replace unaligned store of unaligned load with memmove.
StoreSDNode *ST = cast<StoreSDNode>(N);
if (!DCI.isBeforeLegalize() ||
allowsMemoryAccessForAlignment(*DAG.getContext(), DAG.getDataLayout(),
ST->getMemoryVT(),
*ST->getMemOperand()) ||
ST->isVolatile() || ST->isIndexed()) {
break;
}
SDValue Chain = ST->getChain();
unsigned StoreBits = ST->getMemoryVT().getStoreSizeInBits();
assert((StoreBits % 8) == 0 &&
"Store size in bits must be a multiple of 8");
unsigned Alignment = ST->getAlignment();
if (LoadSDNode *LD = dyn_cast<LoadSDNode>(ST->getValue())) {
if (LD->hasNUsesOfValue(1, 0) && ST->getMemoryVT() == LD->getMemoryVT() &&
LD->getAlignment() == Alignment &&
!LD->isVolatile() && !LD->isIndexed() &&
Chain.reachesChainWithoutSideEffects(SDValue(LD, 1))) {
bool isTail = isInTailCallPosition(DAG, ST, Chain);
return DAG.getMemmove(Chain, dl, ST->getBasePtr(), LD->getBasePtr(),
DAG.getConstant(StoreBits / 8, dl, MVT::i32),
Align(Alignment), false, isTail,
ST->getPointerInfo(), LD->getPointerInfo());
}
}
break;
}
}
return SDValue();
}
void XCoreTargetLowering::computeKnownBitsForTargetNode(const SDValue Op,
KnownBits &Known,
const APInt &DemandedElts,
const SelectionDAG &DAG,
unsigned Depth) const {
Known.resetAll();
switch (Op.getOpcode()) {
default: break;
case XCoreISD::LADD:
case XCoreISD::LSUB:
if (Op.getResNo() == 1) {
// Top bits of carry / borrow are clear.
Known.Zero = APInt::getHighBitsSet(Known.getBitWidth(),
Known.getBitWidth() - 1);
}
break;
case ISD::INTRINSIC_W_CHAIN:
{
unsigned IntNo = cast<ConstantSDNode>(Op.getOperand(1))->getZExtValue();
switch (IntNo) {
case Intrinsic::xcore_getts:
// High bits are known to be zero.
Known.Zero = APInt::getHighBitsSet(Known.getBitWidth(),
Known.getBitWidth() - 16);
break;
case Intrinsic::xcore_int:
case Intrinsic::xcore_inct:
// High bits are known to be zero.
Known.Zero = APInt::getHighBitsSet(Known.getBitWidth(),
Known.getBitWidth() - 8);
break;
case Intrinsic::xcore_testct:
// Result is either 0 or 1.
Known.Zero = APInt::getHighBitsSet(Known.getBitWidth(),
Known.getBitWidth() - 1);
break;
case Intrinsic::xcore_testwct:
// Result is in the range 0 - 4.
Known.Zero = APInt::getHighBitsSet(Known.getBitWidth(),
Known.getBitWidth() - 3);
break;
}
}
break;
}
}
//===----------------------------------------------------------------------===//
// Addressing mode description hooks
//===----------------------------------------------------------------------===//
static inline bool isImmUs(int64_t val)
{
return (val >= 0 && val <= 11);
}
static inline bool isImmUs2(int64_t val)
{
return (val%2 == 0 && isImmUs(val/2));
}
static inline bool isImmUs4(int64_t val)
{
return (val%4 == 0 && isImmUs(val/4));
}
/// isLegalAddressingMode - Return true if the addressing mode represented
/// by AM is legal for this target, for a load/store of the specified type.
bool XCoreTargetLowering::isLegalAddressingMode(const DataLayout &DL,
const AddrMode &AM, Type *Ty,
unsigned AS,
Instruction *I) const {
if (Ty->getTypeID() == Type::VoidTyID)
return AM.Scale == 0 && isImmUs(AM.BaseOffs) && isImmUs4(AM.BaseOffs);
unsigned Size = DL.getTypeAllocSize(Ty);
if (AM.BaseGV) {
return Size >= 4 && !AM.HasBaseReg && AM.Scale == 0 &&
AM.BaseOffs%4 == 0;
}
switch (Size) {
case 1:
// reg + imm
if (AM.Scale == 0) {
return isImmUs(AM.BaseOffs);
}
// reg + reg
return AM.Scale == 1 && AM.BaseOffs == 0;
case 2:
case 3:
// reg + imm
if (AM.Scale == 0) {
return isImmUs2(AM.BaseOffs);
}
// reg + reg<<1
return AM.Scale == 2 && AM.BaseOffs == 0;
default:
// reg + imm
if (AM.Scale == 0) {
return isImmUs4(AM.BaseOffs);
}
// reg + reg<<2
return AM.Scale == 4 && AM.BaseOffs == 0;
}
}
//===----------------------------------------------------------------------===//
// XCore Inline Assembly Support
//===----------------------------------------------------------------------===//
std::pair<unsigned, const TargetRegisterClass *>
XCoreTargetLowering::getRegForInlineAsmConstraint(const TargetRegisterInfo *TRI,
StringRef Constraint,
MVT VT) const {
if (Constraint.size() == 1) {
switch (Constraint[0]) {
default : break;
case 'r':
return std::make_pair(0U, &XCore::GRRegsRegClass);
}
}
// Use the default implementation in TargetLowering to convert the register
// constraint into a member of a register class.
return TargetLowering::getRegForInlineAsmConstraint(TRI, Constraint, VT);
}