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llvm-6502/lib/Target/CellSPU/SPUISelDAGToDAG.cpp
Kalle Raiskila 218c98c284 Add the missing cases to the type->registerclass conversion function. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@115921 91177308-0d34-0410-b5e6-96231b3b80d8
2010-10-07 16:32:42 +00:00

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//===-- SPUISelDAGToDAG.cpp - CellSPU pattern matching inst selector ------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines a pattern matching instruction selector for the Cell SPU,
// converting from a legalized dag to a SPU-target dag.
//
//===----------------------------------------------------------------------===//
#include "SPU.h"
#include "SPUTargetMachine.h"
#include "SPUHazardRecognizers.h"
#include "SPUFrameInfo.h"
#include "SPURegisterNames.h"
#include "SPUTargetMachine.h"
#include "llvm/CodeGen/MachineConstantPool.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/SelectionDAG.h"
#include "llvm/CodeGen/SelectionDAGISel.h"
#include "llvm/CodeGen/PseudoSourceValue.h"
#include "llvm/Target/TargetOptions.h"
#include "llvm/ADT/Statistic.h"
#include "llvm/Constants.h"
#include "llvm/GlobalValue.h"
#include "llvm/Intrinsics.h"
#include "llvm/LLVMContext.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/MathExtras.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
namespace {
//! ConstantSDNode predicate for i32 sign-extended, 10-bit immediates
bool
isI32IntS10Immediate(ConstantSDNode *CN)
{
return isInt<10>(CN->getSExtValue());
}
//! ConstantSDNode predicate for i32 unsigned 10-bit immediate values
bool
isI32IntU10Immediate(ConstantSDNode *CN)
{
return isUInt<10>(CN->getSExtValue());
}
//! ConstantSDNode predicate for i16 sign-extended, 10-bit immediate values
bool
isI16IntS10Immediate(ConstantSDNode *CN)
{
return isInt<10>(CN->getSExtValue());
}
//! ConstantSDNode predicate for i16 unsigned 10-bit immediate values
bool
isI16IntU10Immediate(ConstantSDNode *CN)
{
return isUInt<10>((short) CN->getZExtValue());
}
//! ConstantSDNode predicate for signed 16-bit values
/*!
\arg CN The constant SelectionDAG node holding the value
\arg Imm The returned 16-bit value, if returning true
This predicate tests the value in \a CN to see whether it can be
represented as a 16-bit, sign-extended quantity. Returns true if
this is the case.
*/
bool
isIntS16Immediate(ConstantSDNode *CN, short &Imm)
{
EVT vt = CN->getValueType(0);
Imm = (short) CN->getZExtValue();
if (vt.getSimpleVT() >= MVT::i1 && vt.getSimpleVT() <= MVT::i16) {
return true;
} else if (vt == MVT::i32) {
int32_t i_val = (int32_t) CN->getZExtValue();
short s_val = (short) i_val;
return i_val == s_val;
} else {
int64_t i_val = (int64_t) CN->getZExtValue();
short s_val = (short) i_val;
return i_val == s_val;
}
return false;
}
//! ConstantFPSDNode predicate for representing floats as 16-bit sign ext.
static bool
isFPS16Immediate(ConstantFPSDNode *FPN, short &Imm)
{
EVT vt = FPN->getValueType(0);
if (vt == MVT::f32) {
int val = FloatToBits(FPN->getValueAPF().convertToFloat());
int sval = (int) ((val << 16) >> 16);
Imm = (short) val;
return val == sval;
}
return false;
}
//! Generate the carry-generate shuffle mask.
SDValue getCarryGenerateShufMask(SelectionDAG &DAG, DebugLoc dl) {
SmallVector<SDValue, 16 > ShufBytes;
// Create the shuffle mask for "rotating" the borrow up one register slot
// once the borrow is generated.
ShufBytes.push_back(DAG.getConstant(0x04050607, MVT::i32));
ShufBytes.push_back(DAG.getConstant(0x80808080, MVT::i32));
ShufBytes.push_back(DAG.getConstant(0x0c0d0e0f, MVT::i32));
ShufBytes.push_back(DAG.getConstant(0x80808080, MVT::i32));
return DAG.getNode(ISD::BUILD_VECTOR, dl, MVT::v4i32,
&ShufBytes[0], ShufBytes.size());
}
//! Generate the borrow-generate shuffle mask
SDValue getBorrowGenerateShufMask(SelectionDAG &DAG, DebugLoc dl) {
SmallVector<SDValue, 16 > ShufBytes;
// Create the shuffle mask for "rotating" the borrow up one register slot
// once the borrow is generated.
ShufBytes.push_back(DAG.getConstant(0x04050607, MVT::i32));
ShufBytes.push_back(DAG.getConstant(0xc0c0c0c0, MVT::i32));
ShufBytes.push_back(DAG.getConstant(0x0c0d0e0f, MVT::i32));
ShufBytes.push_back(DAG.getConstant(0xc0c0c0c0, MVT::i32));
return DAG.getNode(ISD::BUILD_VECTOR, dl, MVT::v4i32,
&ShufBytes[0], ShufBytes.size());
}
//===------------------------------------------------------------------===//
/// SPUDAGToDAGISel - Cell SPU-specific code to select SPU machine
/// instructions for SelectionDAG operations.
///
class SPUDAGToDAGISel :
public SelectionDAGISel
{
const SPUTargetMachine &TM;
const SPUTargetLowering &SPUtli;
unsigned GlobalBaseReg;
public:
explicit SPUDAGToDAGISel(SPUTargetMachine &tm) :
SelectionDAGISel(tm),
TM(tm),
SPUtli(*tm.getTargetLowering())
{ }
virtual bool runOnMachineFunction(MachineFunction &MF) {
// Make sure we re-emit a set of the global base reg if necessary
GlobalBaseReg = 0;
SelectionDAGISel::runOnMachineFunction(MF);
return true;
}
/// getI32Imm - Return a target constant with the specified value, of type
/// i32.
inline SDValue getI32Imm(uint32_t Imm) {
return CurDAG->getTargetConstant(Imm, MVT::i32);
}
/// getSmallIPtrImm - Return a target constant of pointer type.
inline SDValue getSmallIPtrImm(unsigned Imm) {
return CurDAG->getTargetConstant(Imm, SPUtli.getPointerTy());
}
SDNode *emitBuildVector(SDNode *bvNode) {
EVT vecVT = bvNode->getValueType(0);
DebugLoc dl = bvNode->getDebugLoc();
// Check to see if this vector can be represented as a CellSPU immediate
// constant by invoking all of the instruction selection predicates:
if (((vecVT == MVT::v8i16) &&
(SPU::get_vec_i16imm(bvNode, *CurDAG, MVT::i16).getNode() != 0)) ||
((vecVT == MVT::v4i32) &&
((SPU::get_vec_i16imm(bvNode, *CurDAG, MVT::i32).getNode() != 0) ||
(SPU::get_ILHUvec_imm(bvNode, *CurDAG, MVT::i32).getNode() != 0) ||
(SPU::get_vec_u18imm(bvNode, *CurDAG, MVT::i32).getNode() != 0) ||
(SPU::get_v4i32_imm(bvNode, *CurDAG).getNode() != 0))) ||
((vecVT == MVT::v2i64) &&
((SPU::get_vec_i16imm(bvNode, *CurDAG, MVT::i64).getNode() != 0) ||
(SPU::get_ILHUvec_imm(bvNode, *CurDAG, MVT::i64).getNode() != 0) ||
(SPU::get_vec_u18imm(bvNode, *CurDAG, MVT::i64).getNode() != 0)))) {
HandleSDNode Dummy(SDValue(bvNode, 0));
if (SDNode *N = Select(bvNode))
return N;
return Dummy.getValue().getNode();
}
// No, need to emit a constant pool spill:
std::vector<Constant*> CV;
for (size_t i = 0; i < bvNode->getNumOperands(); ++i) {
ConstantSDNode *V = cast<ConstantSDNode > (bvNode->getOperand(i));
CV.push_back(const_cast<ConstantInt *>(V->getConstantIntValue()));
}
const Constant *CP = ConstantVector::get(CV);
SDValue CPIdx = CurDAG->getConstantPool(CP, SPUtli.getPointerTy());
unsigned Alignment = cast<ConstantPoolSDNode>(CPIdx)->getAlignment();
SDValue CGPoolOffset =
SPU::LowerConstantPool(CPIdx, *CurDAG, TM);
HandleSDNode Dummy(CurDAG->getLoad(vecVT, dl,
CurDAG->getEntryNode(), CGPoolOffset,
MachinePointerInfo::getConstantPool(),
false, false, Alignment));
CurDAG->ReplaceAllUsesWith(SDValue(bvNode, 0), Dummy.getValue());
if (SDNode *N = SelectCode(Dummy.getValue().getNode()))
return N;
return Dummy.getValue().getNode();
}
/// Select - Convert the specified operand from a target-independent to a
/// target-specific node if it hasn't already been changed.
SDNode *Select(SDNode *N);
//! Emit the instruction sequence for i64 shl
SDNode *SelectSHLi64(SDNode *N, EVT OpVT);
//! Emit the instruction sequence for i64 srl
SDNode *SelectSRLi64(SDNode *N, EVT OpVT);
//! Emit the instruction sequence for i64 sra
SDNode *SelectSRAi64(SDNode *N, EVT OpVT);
//! Emit the necessary sequence for loading i64 constants:
SDNode *SelectI64Constant(SDNode *N, EVT OpVT, DebugLoc dl);
//! Alternate instruction emit sequence for loading i64 constants
SDNode *SelectI64Constant(uint64_t i64const, EVT OpVT, DebugLoc dl);
//! Returns true if the address N is an A-form (local store) address
bool SelectAFormAddr(SDNode *Op, SDValue N, SDValue &Base,
SDValue &Index);
//! D-form address predicate
bool SelectDFormAddr(SDNode *Op, SDValue N, SDValue &Base,
SDValue &Index);
/// Alternate D-form address using i7 offset predicate
bool SelectDForm2Addr(SDNode *Op, SDValue N, SDValue &Disp,
SDValue &Base);
/// D-form address selection workhorse
bool DFormAddressPredicate(SDNode *Op, SDValue N, SDValue &Disp,
SDValue &Base, int minOffset, int maxOffset);
//! Address predicate if N can be expressed as an indexed [r+r] operation.
bool SelectXFormAddr(SDNode *Op, SDValue N, SDValue &Base,
SDValue &Index);
/// SelectInlineAsmMemoryOperand - Implement addressing mode selection for
/// inline asm expressions.
virtual bool SelectInlineAsmMemoryOperand(const SDValue &Op,
char ConstraintCode,
std::vector<SDValue> &OutOps) {
SDValue Op0, Op1;
switch (ConstraintCode) {
default: return true;
case 'm': // memory
if (!SelectDFormAddr(Op.getNode(), Op, Op0, Op1)
&& !SelectAFormAddr(Op.getNode(), Op, Op0, Op1))
SelectXFormAddr(Op.getNode(), Op, Op0, Op1);
break;
case 'o': // offsetable
if (!SelectDFormAddr(Op.getNode(), Op, Op0, Op1)
&& !SelectAFormAddr(Op.getNode(), Op, Op0, Op1)) {
Op0 = Op;
Op1 = getSmallIPtrImm(0);
}
break;
case 'v': // not offsetable
#if 1
llvm_unreachable("InlineAsmMemoryOperand 'v' constraint not handled.");
#else
SelectAddrIdxOnly(Op, Op, Op0, Op1);
#endif
break;
}
OutOps.push_back(Op0);
OutOps.push_back(Op1);
return false;
}
virtual const char *getPassName() const {
return "Cell SPU DAG->DAG Pattern Instruction Selection";
}
/// CreateTargetHazardRecognizer - Return the hazard recognizer to use for
/// this target when scheduling the DAG.
virtual ScheduleHazardRecognizer *CreateTargetHazardRecognizer() {
const TargetInstrInfo *II = TM.getInstrInfo();
assert(II && "No InstrInfo?");
return new SPUHazardRecognizer(*II);
}
private:
SDValue getRC( MVT );
// Include the pieces autogenerated from the target description.
#include "SPUGenDAGISel.inc"
};
}
/*!
\arg Op The ISD instruction operand
\arg N The address to be tested
\arg Base The base address
\arg Index The base address index
*/
bool
SPUDAGToDAGISel::SelectAFormAddr(SDNode *Op, SDValue N, SDValue &Base,
SDValue &Index) {
// These match the addr256k operand type:
EVT OffsVT = MVT::i16;
SDValue Zero = CurDAG->getTargetConstant(0, OffsVT);
switch (N.getOpcode()) {
case ISD::Constant:
case ISD::ConstantPool:
case ISD::GlobalAddress:
report_fatal_error("SPU SelectAFormAddr: Constant/Pool/Global not lowered.");
/*NOTREACHED*/
case ISD::TargetConstant:
case ISD::TargetGlobalAddress:
case ISD::TargetJumpTable:
report_fatal_error("SPUSelectAFormAddr: Target Constant/Pool/Global "
"not wrapped as A-form address.");
/*NOTREACHED*/
case SPUISD::AFormAddr:
// Just load from memory if there's only a single use of the location,
// otherwise, this will get handled below with D-form offset addresses
if (N.hasOneUse()) {
SDValue Op0 = N.getOperand(0);
switch (Op0.getOpcode()) {
case ISD::TargetConstantPool:
case ISD::TargetJumpTable:
Base = Op0;
Index = Zero;
return true;
case ISD::TargetGlobalAddress: {
GlobalAddressSDNode *GSDN = cast<GlobalAddressSDNode>(Op0);
const GlobalValue *GV = GSDN->getGlobal();
if (GV->getAlignment() == 16) {
Base = Op0;
Index = Zero;
return true;
}
break;
}
}
}
break;
}
return false;
}
bool
SPUDAGToDAGISel::SelectDForm2Addr(SDNode *Op, SDValue N, SDValue &Disp,
SDValue &Base) {
const int minDForm2Offset = -(1 << 7);
const int maxDForm2Offset = (1 << 7) - 1;
return DFormAddressPredicate(Op, N, Disp, Base, minDForm2Offset,
maxDForm2Offset);
}
/*!
\arg Op The ISD instruction (ignored)
\arg N The address to be tested
\arg Base Base address register/pointer
\arg Index Base address index
Examine the input address by a base register plus a signed 10-bit
displacement, [r+I10] (D-form address).
\return true if \a N is a D-form address with \a Base and \a Index set
to non-empty SDValue instances.
*/
bool
SPUDAGToDAGISel::SelectDFormAddr(SDNode *Op, SDValue N, SDValue &Base,
SDValue &Index) {
return DFormAddressPredicate(Op, N, Base, Index,
SPUFrameInfo::minFrameOffset(),
SPUFrameInfo::maxFrameOffset());
}
bool
SPUDAGToDAGISel::DFormAddressPredicate(SDNode *Op, SDValue N, SDValue &Base,
SDValue &Index, int minOffset,
int maxOffset) {
unsigned Opc = N.getOpcode();
EVT PtrTy = SPUtli.getPointerTy();
if (Opc == ISD::FrameIndex) {
// Stack frame index must be less than 512 (divided by 16):
FrameIndexSDNode *FIN = cast<FrameIndexSDNode>(N);
int FI = int(FIN->getIndex());
DEBUG(errs() << "SelectDFormAddr: ISD::FrameIndex = "
<< FI << "\n");
if (SPUFrameInfo::FItoStackOffset(FI) < maxOffset) {
Base = CurDAG->getTargetConstant(0, PtrTy);
Index = CurDAG->getTargetFrameIndex(FI, PtrTy);
return true;
}
} else if (Opc == ISD::ADD) {
// Generated by getelementptr
const SDValue Op0 = N.getOperand(0);
const SDValue Op1 = N.getOperand(1);
if ((Op0.getOpcode() == SPUISD::Hi && Op1.getOpcode() == SPUISD::Lo)
|| (Op1.getOpcode() == SPUISD::Hi && Op0.getOpcode() == SPUISD::Lo)) {
Base = CurDAG->getTargetConstant(0, PtrTy);
Index = N;
return true;
} else if (Op1.getOpcode() == ISD::Constant
|| Op1.getOpcode() == ISD::TargetConstant) {
ConstantSDNode *CN = cast<ConstantSDNode>(Op1);
int32_t offset = int32_t(CN->getSExtValue());
if (Op0.getOpcode() == ISD::FrameIndex) {
FrameIndexSDNode *FIN = cast<FrameIndexSDNode>(Op0);
int FI = int(FIN->getIndex());
DEBUG(errs() << "SelectDFormAddr: ISD::ADD offset = " << offset
<< " frame index = " << FI << "\n");
if (SPUFrameInfo::FItoStackOffset(FI) < maxOffset) {
Base = CurDAG->getTargetConstant(offset, PtrTy);
Index = CurDAG->getTargetFrameIndex(FI, PtrTy);
return true;
}
} else if (offset > minOffset && offset < maxOffset) {
Base = CurDAG->getTargetConstant(offset, PtrTy);
Index = Op0;
return true;
}
} else if (Op0.getOpcode() == ISD::Constant
|| Op0.getOpcode() == ISD::TargetConstant) {
ConstantSDNode *CN = cast<ConstantSDNode>(Op0);
int32_t offset = int32_t(CN->getSExtValue());
if (Op1.getOpcode() == ISD::FrameIndex) {
FrameIndexSDNode *FIN = cast<FrameIndexSDNode>(Op1);
int FI = int(FIN->getIndex());
DEBUG(errs() << "SelectDFormAddr: ISD::ADD offset = " << offset
<< " frame index = " << FI << "\n");
if (SPUFrameInfo::FItoStackOffset(FI) < maxOffset) {
Base = CurDAG->getTargetConstant(offset, PtrTy);
Index = CurDAG->getTargetFrameIndex(FI, PtrTy);
return true;
}
} else if (offset > minOffset && offset < maxOffset) {
Base = CurDAG->getTargetConstant(offset, PtrTy);
Index = Op1;
return true;
}
}
} else if (Opc == SPUISD::IndirectAddr) {
// Indirect with constant offset -> D-Form address
const SDValue Op0 = N.getOperand(0);
const SDValue Op1 = N.getOperand(1);
if (Op0.getOpcode() == SPUISD::Hi
&& Op1.getOpcode() == SPUISD::Lo) {
// (SPUindirect (SPUhi <arg>, 0), (SPUlo <arg>, 0))
Base = CurDAG->getTargetConstant(0, PtrTy);
Index = N;
return true;
} else if (isa<ConstantSDNode>(Op0) || isa<ConstantSDNode>(Op1)) {
int32_t offset = 0;
SDValue idxOp;
if (isa<ConstantSDNode>(Op1)) {
ConstantSDNode *CN = cast<ConstantSDNode>(Op1);
offset = int32_t(CN->getSExtValue());
idxOp = Op0;
} else if (isa<ConstantSDNode>(Op0)) {
ConstantSDNode *CN = cast<ConstantSDNode>(Op0);
offset = int32_t(CN->getSExtValue());
idxOp = Op1;
}
if (offset >= minOffset && offset <= maxOffset) {
Base = CurDAG->getTargetConstant(offset, PtrTy);
Index = idxOp;
return true;
}
}
} else if (Opc == SPUISD::AFormAddr) {
Base = CurDAG->getTargetConstant(0, N.getValueType());
Index = N;
return true;
} else if (Opc == SPUISD::LDRESULT) {
Base = CurDAG->getTargetConstant(0, N.getValueType());
Index = N;
return true;
} else if (Opc == ISD::Register
||Opc == ISD::CopyFromReg
||Opc == ISD::UNDEF
||Opc == ISD::Constant) {
unsigned OpOpc = Op->getOpcode();
if (OpOpc == ISD::STORE || OpOpc == ISD::LOAD) {
// Direct load/store without getelementptr
SDValue Offs;
Offs = ((OpOpc == ISD::STORE) ? Op->getOperand(3) : Op->getOperand(2));
if (Offs.getOpcode() == ISD::Constant || Offs.getOpcode() == ISD::UNDEF) {
if (Offs.getOpcode() == ISD::UNDEF)
Offs = CurDAG->getTargetConstant(0, Offs.getValueType());
Base = Offs;
Index = N;
return true;
}
} else {
/* If otherwise unadorned, default to D-form address with 0 offset: */
if (Opc == ISD::CopyFromReg) {
Index = N.getOperand(1);
} else {
Index = N;
}
Base = CurDAG->getTargetConstant(0, Index.getValueType());
return true;
}
}
return false;
}
/*!
\arg Op The ISD instruction operand
\arg N The address operand
\arg Base The base pointer operand
\arg Index The offset/index operand
If the address \a N can be expressed as an A-form or D-form address, returns
false. Otherwise, creates two operands, Base and Index that will become the
(r)(r) X-form address.
*/
bool
SPUDAGToDAGISel::SelectXFormAddr(SDNode *Op, SDValue N, SDValue &Base,
SDValue &Index) {
if (!SelectAFormAddr(Op, N, Base, Index)
&& !SelectDFormAddr(Op, N, Base, Index)) {
// If the address is neither A-form or D-form, punt and use an X-form
// address:
Base = N.getOperand(1);
Index = N.getOperand(0);
return true;
}
return false;
}
/*!
Utility function to use with COPY_TO_REGCLASS instructions. Returns a SDValue
to be used as the last parameter of a
CurDAG->getMachineNode(COPY_TO_REGCLASS,..., ) function call
\arg VT the value type for which we want a register class
*/
SDValue SPUDAGToDAGISel::getRC( MVT VT ) {
switch( VT.SimpleTy ) {
case MVT::i8:
return CurDAG->getTargetConstant(SPU::R8CRegClass.getID(), MVT::i32);
break;
case MVT::i16:
return CurDAG->getTargetConstant(SPU::R16CRegClass.getID(), MVT::i32);
break;
case MVT::i32:
return CurDAG->getTargetConstant(SPU::R32CRegClass.getID(), MVT::i32);
break;
case MVT::f32:
return CurDAG->getTargetConstant(SPU::R32FPRegClass.getID(), MVT::i32);
break;
case MVT::i64:
return CurDAG->getTargetConstant(SPU::R64CRegClass.getID(), MVT::i32);
break;
case MVT::v16i8:
case MVT::v8i16:
case MVT::v4i32:
case MVT::v4f32:
case MVT::v2i64:
case MVT::v2f64:
return CurDAG->getTargetConstant(SPU::VECREGRegClass.getID(), MVT::i32);
break;
default:
assert( false && "add a new case here" );
}
return SDValue();
}
//! Convert the operand from a target-independent to a target-specific node
/*!
*/
SDNode *
SPUDAGToDAGISel::Select(SDNode *N) {
unsigned Opc = N->getOpcode();
int n_ops = -1;
unsigned NewOpc;
EVT OpVT = N->getValueType(0);
SDValue Ops[8];
DebugLoc dl = N->getDebugLoc();
if (N->isMachineOpcode())
return NULL; // Already selected.
if (Opc == ISD::FrameIndex) {
int FI = cast<FrameIndexSDNode>(N)->getIndex();
SDValue TFI = CurDAG->getTargetFrameIndex(FI, N->getValueType(0));
SDValue Imm0 = CurDAG->getTargetConstant(0, N->getValueType(0));
if (FI < 128) {
NewOpc = SPU::AIr32;
Ops[0] = TFI;
Ops[1] = Imm0;
n_ops = 2;
} else {
NewOpc = SPU::Ar32;
Ops[0] = CurDAG->getRegister(SPU::R1, N->getValueType(0));
Ops[1] = SDValue(CurDAG->getMachineNode(SPU::ILAr32, dl,
N->getValueType(0), TFI, Imm0),
0);
n_ops = 2;
}
} else if (Opc == ISD::Constant && OpVT == MVT::i64) {
// Catch the i64 constants that end up here. Note: The backend doesn't
// attempt to legalize the constant (it's useless because DAGCombiner
// will insert 64-bit constants and we can't stop it).
return SelectI64Constant(N, OpVT, N->getDebugLoc());
} else if ((Opc == ISD::ZERO_EXTEND || Opc == ISD::ANY_EXTEND)
&& OpVT == MVT::i64) {
SDValue Op0 = N->getOperand(0);
EVT Op0VT = Op0.getValueType();
EVT Op0VecVT = EVT::getVectorVT(*CurDAG->getContext(),
Op0VT, (128 / Op0VT.getSizeInBits()));
EVT OpVecVT = EVT::getVectorVT(*CurDAG->getContext(),
OpVT, (128 / OpVT.getSizeInBits()));
SDValue shufMask;
switch (Op0VT.getSimpleVT().SimpleTy) {
default:
report_fatal_error("CellSPU Select: Unhandled zero/any extend EVT");
/*NOTREACHED*/
case MVT::i32:
shufMask = CurDAG->getNode(ISD::BUILD_VECTOR, dl, MVT::v4i32,
CurDAG->getConstant(0x80808080, MVT::i32),
CurDAG->getConstant(0x00010203, MVT::i32),
CurDAG->getConstant(0x80808080, MVT::i32),
CurDAG->getConstant(0x08090a0b, MVT::i32));
break;
case MVT::i16:
shufMask = CurDAG->getNode(ISD::BUILD_VECTOR, dl, MVT::v4i32,
CurDAG->getConstant(0x80808080, MVT::i32),
CurDAG->getConstant(0x80800203, MVT::i32),
CurDAG->getConstant(0x80808080, MVT::i32),
CurDAG->getConstant(0x80800a0b, MVT::i32));
break;
case MVT::i8:
shufMask = CurDAG->getNode(ISD::BUILD_VECTOR, dl, MVT::v4i32,
CurDAG->getConstant(0x80808080, MVT::i32),
CurDAG->getConstant(0x80808003, MVT::i32),
CurDAG->getConstant(0x80808080, MVT::i32),
CurDAG->getConstant(0x8080800b, MVT::i32));
break;
}
SDNode *shufMaskLoad = emitBuildVector(shufMask.getNode());
HandleSDNode PromoteScalar(CurDAG->getNode(SPUISD::PREFSLOT2VEC, dl,
Op0VecVT, Op0));
SDValue PromScalar;
if (SDNode *N = SelectCode(PromoteScalar.getValue().getNode()))
PromScalar = SDValue(N, 0);
else
PromScalar = PromoteScalar.getValue();
SDValue zextShuffle =
CurDAG->getNode(SPUISD::SHUFB, dl, OpVecVT,
PromScalar, PromScalar,
SDValue(shufMaskLoad, 0));
HandleSDNode Dummy2(zextShuffle);
if (SDNode *N = SelectCode(Dummy2.getValue().getNode()))
zextShuffle = SDValue(N, 0);
else
zextShuffle = Dummy2.getValue();
HandleSDNode Dummy(CurDAG->getNode(SPUISD::VEC2PREFSLOT, dl, OpVT,
zextShuffle));
CurDAG->ReplaceAllUsesWith(N, Dummy.getValue().getNode());
SelectCode(Dummy.getValue().getNode());
return Dummy.getValue().getNode();
} else if (Opc == ISD::ADD && (OpVT == MVT::i64 || OpVT == MVT::v2i64)) {
SDNode *CGLoad =
emitBuildVector(getCarryGenerateShufMask(*CurDAG, dl).getNode());
HandleSDNode Dummy(CurDAG->getNode(SPUISD::ADD64_MARKER, dl, OpVT,
N->getOperand(0), N->getOperand(1),
SDValue(CGLoad, 0)));
CurDAG->ReplaceAllUsesWith(N, Dummy.getValue().getNode());
if (SDNode *N = SelectCode(Dummy.getValue().getNode()))
return N;
return Dummy.getValue().getNode();
} else if (Opc == ISD::SUB && (OpVT == MVT::i64 || OpVT == MVT::v2i64)) {
SDNode *CGLoad =
emitBuildVector(getBorrowGenerateShufMask(*CurDAG, dl).getNode());
HandleSDNode Dummy(CurDAG->getNode(SPUISD::SUB64_MARKER, dl, OpVT,
N->getOperand(0), N->getOperand(1),
SDValue(CGLoad, 0)));
CurDAG->ReplaceAllUsesWith(N, Dummy.getValue().getNode());
if (SDNode *N = SelectCode(Dummy.getValue().getNode()))
return N;
return Dummy.getValue().getNode();
} else if (Opc == ISD::MUL && (OpVT == MVT::i64 || OpVT == MVT::v2i64)) {
SDNode *CGLoad =
emitBuildVector(getCarryGenerateShufMask(*CurDAG, dl).getNode());
HandleSDNode Dummy(CurDAG->getNode(SPUISD::MUL64_MARKER, dl, OpVT,
N->getOperand(0), N->getOperand(1),
SDValue(CGLoad, 0)));
CurDAG->ReplaceAllUsesWith(N, Dummy.getValue().getNode());
if (SDNode *N = SelectCode(Dummy.getValue().getNode()))
return N;
return Dummy.getValue().getNode();
} else if (Opc == ISD::TRUNCATE) {
SDValue Op0 = N->getOperand(0);
if ((Op0.getOpcode() == ISD::SRA || Op0.getOpcode() == ISD::SRL)
&& OpVT == MVT::i32
&& Op0.getValueType() == MVT::i64) {
// Catch (truncate:i32 ([sra|srl]:i64 arg, c), where c >= 32
//
// Take advantage of the fact that the upper 32 bits are in the
// i32 preferred slot and avoid shuffle gymnastics:
ConstantSDNode *CN = dyn_cast<ConstantSDNode>(Op0.getOperand(1));
if (CN != 0) {
unsigned shift_amt = unsigned(CN->getZExtValue());
if (shift_amt >= 32) {
SDNode *hi32 =
CurDAG->getMachineNode(TargetOpcode::COPY_TO_REGCLASS, dl, OpVT,
Op0.getOperand(0), getRC(MVT::i32));
shift_amt -= 32;
if (shift_amt > 0) {
// Take care of the additional shift, if present:
SDValue shift = CurDAG->getTargetConstant(shift_amt, MVT::i32);
unsigned Opc = SPU::ROTMAIr32_i32;
if (Op0.getOpcode() == ISD::SRL)
Opc = SPU::ROTMr32;
hi32 = CurDAG->getMachineNode(Opc, dl, OpVT, SDValue(hi32, 0),
shift);
}
return hi32;
}
}
}
} else if (Opc == ISD::SHL) {
if (OpVT == MVT::i64)
return SelectSHLi64(N, OpVT);
} else if (Opc == ISD::SRL) {
if (OpVT == MVT::i64)
return SelectSRLi64(N, OpVT);
} else if (Opc == ISD::SRA) {
if (OpVT == MVT::i64)
return SelectSRAi64(N, OpVT);
} else if (Opc == ISD::FNEG
&& (OpVT == MVT::f64 || OpVT == MVT::v2f64)) {
DebugLoc dl = N->getDebugLoc();
// Check if the pattern is a special form of DFNMS:
// (fneg (fsub (fmul R64FP:$rA, R64FP:$rB), R64FP:$rC))
SDValue Op0 = N->getOperand(0);
if (Op0.getOpcode() == ISD::FSUB) {
SDValue Op00 = Op0.getOperand(0);
if (Op00.getOpcode() == ISD::FMUL) {
unsigned Opc = SPU::DFNMSf64;
if (OpVT == MVT::v2f64)
Opc = SPU::DFNMSv2f64;
return CurDAG->getMachineNode(Opc, dl, OpVT,
Op00.getOperand(0),
Op00.getOperand(1),
Op0.getOperand(1));
}
}
SDValue negConst = CurDAG->getConstant(0x8000000000000000ULL, MVT::i64);
SDNode *signMask = 0;
unsigned Opc = SPU::XORfneg64;
if (OpVT == MVT::f64) {
signMask = SelectI64Constant(negConst.getNode(), MVT::i64, dl);
} else if (OpVT == MVT::v2f64) {
Opc = SPU::XORfnegvec;
signMask = emitBuildVector(CurDAG->getNode(ISD::BUILD_VECTOR, dl,
MVT::v2i64,
negConst, negConst).getNode());
}
return CurDAG->getMachineNode(Opc, dl, OpVT,
N->getOperand(0), SDValue(signMask, 0));
} else if (Opc == ISD::FABS) {
if (OpVT == MVT::f64) {
SDNode *signMask = SelectI64Constant(0x7fffffffffffffffULL, MVT::i64, dl);
return CurDAG->getMachineNode(SPU::ANDfabs64, dl, OpVT,
N->getOperand(0), SDValue(signMask, 0));
} else if (OpVT == MVT::v2f64) {
SDValue absConst = CurDAG->getConstant(0x7fffffffffffffffULL, MVT::i64);
SDValue absVec = CurDAG->getNode(ISD::BUILD_VECTOR, dl, MVT::v2i64,
absConst, absConst);
SDNode *signMask = emitBuildVector(absVec.getNode());
return CurDAG->getMachineNode(SPU::ANDfabsvec, dl, OpVT,
N->getOperand(0), SDValue(signMask, 0));
}
} else if (Opc == SPUISD::LDRESULT) {
// Custom select instructions for LDRESULT
EVT VT = N->getValueType(0);
SDValue Arg = N->getOperand(0);
SDValue Chain = N->getOperand(1);
SDNode *Result;
Result = CurDAG->getMachineNode(TargetOpcode::COPY_TO_REGCLASS, dl, VT,
MVT::Other, Arg,
getRC( VT.getSimpleVT()), Chain);
return Result;
} else if (Opc == SPUISD::IndirectAddr) {
// Look at the operands: SelectCode() will catch the cases that aren't
// specifically handled here.
//
// SPUInstrInfo catches the following patterns:
// (SPUindirect (SPUhi ...), (SPUlo ...))
// (SPUindirect $sp, imm)
EVT VT = N->getValueType(0);
SDValue Op0 = N->getOperand(0);
SDValue Op1 = N->getOperand(1);
RegisterSDNode *RN;
if ((Op0.getOpcode() != SPUISD::Hi && Op1.getOpcode() != SPUISD::Lo)
|| (Op0.getOpcode() == ISD::Register
&& ((RN = dyn_cast<RegisterSDNode>(Op0.getNode())) != 0
&& RN->getReg() != SPU::R1))) {
NewOpc = SPU::Ar32;
Ops[1] = Op1;
if (Op1.getOpcode() == ISD::Constant) {
ConstantSDNode *CN = cast<ConstantSDNode>(Op1);
Op1 = CurDAG->getTargetConstant(CN->getSExtValue(), VT);
if (isInt<10>(CN->getSExtValue())) {
NewOpc = SPU::AIr32;
Ops[1] = Op1;
} else {
Ops[1] = SDValue(CurDAG->getMachineNode(SPU::ILr32, dl,
N->getValueType(0),
Op1),
0);
}
}
Ops[0] = Op0;
n_ops = 2;
}
}
if (n_ops > 0) {
if (N->hasOneUse())
return CurDAG->SelectNodeTo(N, NewOpc, OpVT, Ops, n_ops);
else
return CurDAG->getMachineNode(NewOpc, dl, OpVT, Ops, n_ops);
} else
return SelectCode(N);
}
/*!
* Emit the instruction sequence for i64 left shifts. The basic algorithm
* is to fill the bottom two word slots with zeros so that zeros are shifted
* in as the entire quadword is shifted left.
*
* \note This code could also be used to implement v2i64 shl.
*
* @param Op The shl operand
* @param OpVT Op's machine value value type (doesn't need to be passed, but
* makes life easier.)
* @return The SDNode with the entire instruction sequence
*/
SDNode *
SPUDAGToDAGISel::SelectSHLi64(SDNode *N, EVT OpVT) {
SDValue Op0 = N->getOperand(0);
EVT VecVT = EVT::getVectorVT(*CurDAG->getContext(),
OpVT, (128 / OpVT.getSizeInBits()));
SDValue ShiftAmt = N->getOperand(1);
EVT ShiftAmtVT = ShiftAmt.getValueType();
SDNode *VecOp0, *SelMask, *ZeroFill, *Shift = 0;
SDValue SelMaskVal;
DebugLoc dl = N->getDebugLoc();
VecOp0 = CurDAG->getMachineNode(TargetOpcode::COPY_TO_REGCLASS, dl, VecVT,
Op0, getRC(MVT::v2i64) );
SelMaskVal = CurDAG->getTargetConstant(0xff00ULL, MVT::i16);
SelMask = CurDAG->getMachineNode(SPU::FSMBIv2i64, dl, VecVT, SelMaskVal);
ZeroFill = CurDAG->getMachineNode(SPU::ILv2i64, dl, VecVT,
CurDAG->getTargetConstant(0, OpVT));
VecOp0 = CurDAG->getMachineNode(SPU::SELBv2i64, dl, VecVT,
SDValue(ZeroFill, 0),
SDValue(VecOp0, 0),
SDValue(SelMask, 0));
if (ConstantSDNode *CN = dyn_cast<ConstantSDNode>(ShiftAmt)) {
unsigned bytes = unsigned(CN->getZExtValue()) >> 3;
unsigned bits = unsigned(CN->getZExtValue()) & 7;
if (bytes > 0) {
Shift =
CurDAG->getMachineNode(SPU::SHLQBYIv2i64, dl, VecVT,
SDValue(VecOp0, 0),
CurDAG->getTargetConstant(bytes, ShiftAmtVT));
}
if (bits > 0) {
Shift =
CurDAG->getMachineNode(SPU::SHLQBIIv2i64, dl, VecVT,
SDValue((Shift != 0 ? Shift : VecOp0), 0),
CurDAG->getTargetConstant(bits, ShiftAmtVT));
}
} else {
SDNode *Bytes =
CurDAG->getMachineNode(SPU::ROTMIr32, dl, ShiftAmtVT,
ShiftAmt,
CurDAG->getTargetConstant(3, ShiftAmtVT));
SDNode *Bits =
CurDAG->getMachineNode(SPU::ANDIr32, dl, ShiftAmtVT,
ShiftAmt,
CurDAG->getTargetConstant(7, ShiftAmtVT));
Shift =
CurDAG->getMachineNode(SPU::SHLQBYv2i64, dl, VecVT,
SDValue(VecOp0, 0), SDValue(Bytes, 0));
Shift =
CurDAG->getMachineNode(SPU::SHLQBIv2i64, dl, VecVT,
SDValue(Shift, 0), SDValue(Bits, 0));
}
return CurDAG->getMachineNode(TargetOpcode::COPY_TO_REGCLASS, dl,
OpVT, SDValue(Shift, 0), getRC(MVT::i64));
}
/*!
* Emit the instruction sequence for i64 logical right shifts.
*
* @param Op The shl operand
* @param OpVT Op's machine value value type (doesn't need to be passed, but
* makes life easier.)
* @return The SDNode with the entire instruction sequence
*/
SDNode *
SPUDAGToDAGISel::SelectSRLi64(SDNode *N, EVT OpVT) {
SDValue Op0 = N->getOperand(0);
EVT VecVT = EVT::getVectorVT(*CurDAG->getContext(),
OpVT, (128 / OpVT.getSizeInBits()));
SDValue ShiftAmt = N->getOperand(1);
EVT ShiftAmtVT = ShiftAmt.getValueType();
SDNode *VecOp0, *Shift = 0;
DebugLoc dl = N->getDebugLoc();
VecOp0 = CurDAG->getMachineNode(TargetOpcode::COPY_TO_REGCLASS, dl, VecVT,
Op0, getRC(MVT::v2i64) );
if (ConstantSDNode *CN = dyn_cast<ConstantSDNode>(ShiftAmt)) {
unsigned bytes = unsigned(CN->getZExtValue()) >> 3;
unsigned bits = unsigned(CN->getZExtValue()) & 7;
if (bytes > 0) {
Shift =
CurDAG->getMachineNode(SPU::ROTQMBYIv2i64, dl, VecVT,
SDValue(VecOp0, 0),
CurDAG->getTargetConstant(bytes, ShiftAmtVT));
}
if (bits > 0) {
Shift =
CurDAG->getMachineNode(SPU::ROTQMBIIv2i64, dl, VecVT,
SDValue((Shift != 0 ? Shift : VecOp0), 0),
CurDAG->getTargetConstant(bits, ShiftAmtVT));
}
} else {
SDNode *Bytes =
CurDAG->getMachineNode(SPU::ROTMIr32, dl, ShiftAmtVT,
ShiftAmt,
CurDAG->getTargetConstant(3, ShiftAmtVT));
SDNode *Bits =
CurDAG->getMachineNode(SPU::ANDIr32, dl, ShiftAmtVT,
ShiftAmt,
CurDAG->getTargetConstant(7, ShiftAmtVT));
// Ensure that the shift amounts are negated!
Bytes = CurDAG->getMachineNode(SPU::SFIr32, dl, ShiftAmtVT,
SDValue(Bytes, 0),
CurDAG->getTargetConstant(0, ShiftAmtVT));
Bits = CurDAG->getMachineNode(SPU::SFIr32, dl, ShiftAmtVT,
SDValue(Bits, 0),
CurDAG->getTargetConstant(0, ShiftAmtVT));
Shift =
CurDAG->getMachineNode(SPU::ROTQMBYv2i64, dl, VecVT,
SDValue(VecOp0, 0), SDValue(Bytes, 0));
Shift =
CurDAG->getMachineNode(SPU::ROTQMBIv2i64, dl, VecVT,
SDValue(Shift, 0), SDValue(Bits, 0));
}
return CurDAG->getMachineNode(TargetOpcode::COPY_TO_REGCLASS, dl,
OpVT, SDValue(Shift, 0), getRC(MVT::i64));
}
/*!
* Emit the instruction sequence for i64 arithmetic right shifts.
*
* @param Op The shl operand
* @param OpVT Op's machine value value type (doesn't need to be passed, but
* makes life easier.)
* @return The SDNode with the entire instruction sequence
*/
SDNode *
SPUDAGToDAGISel::SelectSRAi64(SDNode *N, EVT OpVT) {
// Promote Op0 to vector
EVT VecVT = EVT::getVectorVT(*CurDAG->getContext(),
OpVT, (128 / OpVT.getSizeInBits()));
SDValue ShiftAmt = N->getOperand(1);
EVT ShiftAmtVT = ShiftAmt.getValueType();
DebugLoc dl = N->getDebugLoc();
SDNode *VecOp0 =
CurDAG->getMachineNode(TargetOpcode::COPY_TO_REGCLASS, dl,
VecVT, N->getOperand(0), getRC(MVT::v2i64));
SDValue SignRotAmt = CurDAG->getTargetConstant(31, ShiftAmtVT);
SDNode *SignRot =
CurDAG->getMachineNode(SPU::ROTMAIv2i64_i32, dl, MVT::v2i64,
SDValue(VecOp0, 0), SignRotAmt);
SDNode *UpperHalfSign =
CurDAG->getMachineNode(TargetOpcode::COPY_TO_REGCLASS, dl,
MVT::i32, SDValue(SignRot, 0), getRC(MVT::i32));
SDNode *UpperHalfSignMask =
CurDAG->getMachineNode(SPU::FSM64r32, dl, VecVT, SDValue(UpperHalfSign, 0));
SDNode *UpperLowerMask =
CurDAG->getMachineNode(SPU::FSMBIv2i64, dl, VecVT,
CurDAG->getTargetConstant(0xff00ULL, MVT::i16));
SDNode *UpperLowerSelect =
CurDAG->getMachineNode(SPU::SELBv2i64, dl, VecVT,
SDValue(UpperHalfSignMask, 0),
SDValue(VecOp0, 0),
SDValue(UpperLowerMask, 0));
SDNode *Shift = 0;
if (ConstantSDNode *CN = dyn_cast<ConstantSDNode>(ShiftAmt)) {
unsigned bytes = unsigned(CN->getZExtValue()) >> 3;
unsigned bits = unsigned(CN->getZExtValue()) & 7;
if (bytes > 0) {
bytes = 31 - bytes;
Shift =
CurDAG->getMachineNode(SPU::ROTQBYIv2i64, dl, VecVT,
SDValue(UpperLowerSelect, 0),
CurDAG->getTargetConstant(bytes, ShiftAmtVT));
}
if (bits > 0) {
bits = 8 - bits;
Shift =
CurDAG->getMachineNode(SPU::ROTQBIIv2i64, dl, VecVT,
SDValue((Shift != 0 ? Shift : UpperLowerSelect), 0),
CurDAG->getTargetConstant(bits, ShiftAmtVT));
}
} else {
SDNode *NegShift =
CurDAG->getMachineNode(SPU::SFIr32, dl, ShiftAmtVT,
ShiftAmt, CurDAG->getTargetConstant(0, ShiftAmtVT));
Shift =
CurDAG->getMachineNode(SPU::ROTQBYBIv2i64_r32, dl, VecVT,
SDValue(UpperLowerSelect, 0), SDValue(NegShift, 0));
Shift =
CurDAG->getMachineNode(SPU::ROTQBIv2i64, dl, VecVT,
SDValue(Shift, 0), SDValue(NegShift, 0));
}
return CurDAG->getMachineNode(TargetOpcode::COPY_TO_REGCLASS, dl,
OpVT, SDValue(Shift, 0), getRC(MVT::i64));
}
/*!
Do the necessary magic necessary to load a i64 constant
*/
SDNode *SPUDAGToDAGISel::SelectI64Constant(SDNode *N, EVT OpVT,
DebugLoc dl) {
ConstantSDNode *CN = cast<ConstantSDNode>(N);
return SelectI64Constant(CN->getZExtValue(), OpVT, dl);
}
SDNode *SPUDAGToDAGISel::SelectI64Constant(uint64_t Value64, EVT OpVT,
DebugLoc dl) {
EVT OpVecVT = EVT::getVectorVT(*CurDAG->getContext(), OpVT, 2);
SDValue i64vec =
SPU::LowerV2I64Splat(OpVecVT, *CurDAG, Value64, dl);
// Here's where it gets interesting, because we have to parse out the
// subtree handed back in i64vec:
if (i64vec.getOpcode() == ISD::BIT_CONVERT) {
// The degenerate case where the upper and lower bits in the splat are
// identical:
SDValue Op0 = i64vec.getOperand(0);
ReplaceUses(i64vec, Op0);
return CurDAG->getMachineNode(TargetOpcode::COPY_TO_REGCLASS, dl, OpVT,
SDValue(emitBuildVector(Op0.getNode()), 0),
getRC(MVT::i64));
} else if (i64vec.getOpcode() == SPUISD::SHUFB) {
SDValue lhs = i64vec.getOperand(0);
SDValue rhs = i64vec.getOperand(1);
SDValue shufmask = i64vec.getOperand(2);
if (lhs.getOpcode() == ISD::BIT_CONVERT) {
ReplaceUses(lhs, lhs.getOperand(0));
lhs = lhs.getOperand(0);
}
SDNode *lhsNode = (lhs.getNode()->isMachineOpcode()
? lhs.getNode()
: emitBuildVector(lhs.getNode()));
if (rhs.getOpcode() == ISD::BIT_CONVERT) {
ReplaceUses(rhs, rhs.getOperand(0));
rhs = rhs.getOperand(0);
}
SDNode *rhsNode = (rhs.getNode()->isMachineOpcode()
? rhs.getNode()
: emitBuildVector(rhs.getNode()));
if (shufmask.getOpcode() == ISD::BIT_CONVERT) {
ReplaceUses(shufmask, shufmask.getOperand(0));
shufmask = shufmask.getOperand(0);
}
SDNode *shufMaskNode = (shufmask.getNode()->isMachineOpcode()
? shufmask.getNode()
: emitBuildVector(shufmask.getNode()));
SDValue shufNode =
CurDAG->getNode(SPUISD::SHUFB, dl, OpVecVT,
SDValue(lhsNode, 0), SDValue(rhsNode, 0),
SDValue(shufMaskNode, 0));
HandleSDNode Dummy(shufNode);
SDNode *SN = SelectCode(Dummy.getValue().getNode());
if (SN == 0) SN = Dummy.getValue().getNode();
return CurDAG->getMachineNode(TargetOpcode::COPY_TO_REGCLASS, dl,
OpVT, SDValue(SN, 0), getRC(MVT::i64));
} else if (i64vec.getOpcode() == ISD::BUILD_VECTOR) {
return CurDAG->getMachineNode(TargetOpcode::COPY_TO_REGCLASS, dl, OpVT,
SDValue(emitBuildVector(i64vec.getNode()), 0),
getRC(MVT::i64));
} else {
report_fatal_error("SPUDAGToDAGISel::SelectI64Constant: Unhandled i64vec"
"condition");
}
}
/// createSPUISelDag - This pass converts a legalized DAG into a
/// SPU-specific DAG, ready for instruction scheduling.
///
FunctionPass *llvm::createSPUISelDag(SPUTargetMachine &TM) {
return new SPUDAGToDAGISel(TM);
}
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