//===-- XCoreISelDAGToDAG.cpp - A dag to dag inst selector for XCore ------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file defines an instruction selector for the XCore target.
//
//===----------------------------------------------------------------------===//
#include "XCore.h"
#include "XCoreTargetMachine.h"
#include "llvm/DerivedTypes.h"
#include "llvm/Function.h"
#include "llvm/Intrinsics.h"
#include "llvm/CallingConv.h"
#include "llvm/Constants.h"
#include "llvm/LLVMContext.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/CodeGen/SelectionDAG.h"
#include "llvm/CodeGen/SelectionDAGISel.h"
#include "llvm/Target/TargetLowering.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
/// XCoreDAGToDAGISel - XCore specific code to select XCore machine
/// instructions for SelectionDAG operations.
///
namespace {
class XCoreDAGToDAGISel : public SelectionDAGISel {
const XCoreTargetLowering &Lowering;
const XCoreSubtarget &Subtarget;
public:
XCoreDAGToDAGISel(XCoreTargetMachine &TM, CodeGenOpt::Level OptLevel)
: SelectionDAGISel(TM, OptLevel),
Lowering(*TM.getTargetLowering()),
Subtarget(*TM.getSubtargetImpl()) { }
SDNode *Select(SDNode *N);
SDNode *SelectBRIND(SDNode *N);
/// getI32Imm - Return a target constant with the specified value, of type
/// i32.
inline SDValue getI32Imm(unsigned Imm) {
return CurDAG->getTargetConstant(Imm, MVT::i32);
}
inline bool immMskBitp(SDNode *inN) const {
ConstantSDNode *N = cast<ConstantSDNode>(inN);
uint32_t value = (uint32_t)N->getZExtValue();
if (!isMask_32(value)) {
return false;
}
int msksize = 32 - CountLeadingZeros_32(value);
return (msksize >= 1 && msksize <= 8) ||
msksize == 16 || msksize == 24 || msksize == 32;
}
// Complex Pattern Selectors.
bool SelectADDRspii(SDValue Addr, SDValue &Base, SDValue &Offset);
bool SelectADDRdpii(SDValue Addr, SDValue &Base, SDValue &Offset);
bool SelectADDRcpii(SDValue Addr, SDValue &Base, SDValue &Offset);
virtual const char *getPassName() const {
return "XCore DAG->DAG Pattern Instruction Selection";
}
// Include the pieces autogenerated from the target description.
#include "XCoreGenDAGISel.inc"
};
} // end anonymous namespace
/// createXCoreISelDag - This pass converts a legalized DAG into a
/// XCore-specific DAG, ready for instruction scheduling.
///
FunctionPass *llvm::createXCoreISelDag(XCoreTargetMachine &TM,
CodeGenOpt::Level OptLevel) {
return new XCoreDAGToDAGISel(TM, OptLevel);
}
bool XCoreDAGToDAGISel::SelectADDRspii(SDValue Addr, SDValue &Base,
SDValue &Offset) {
FrameIndexSDNode *FIN = 0;
if ((FIN = dyn_cast<FrameIndexSDNode>(Addr))) {
Base = CurDAG->getTargetFrameIndex(FIN->getIndex(), MVT::i32);
Offset = CurDAG->getTargetConstant(0, MVT::i32);
return true;
}
if (Addr.getOpcode() == ISD::ADD) {
ConstantSDNode *CN = 0;
if ((FIN = dyn_cast<FrameIndexSDNode>(Addr.getOperand(0)))
&& (CN = dyn_cast<ConstantSDNode>(Addr.getOperand(1)))
&& (CN->getSExtValue() % 4 == 0 && CN->getSExtValue() >= 0)) {
// Constant positive word offset from frame index
Base = CurDAG->getTargetFrameIndex(FIN->getIndex(), MVT::i32);
Offset = CurDAG->getTargetConstant(CN->getSExtValue(), MVT::i32);
return true;
}
}
return false;
}
bool XCoreDAGToDAGISel::SelectADDRdpii(SDValue Addr, SDValue &Base,
SDValue &Offset) {
if (Addr.getOpcode() == XCoreISD::DPRelativeWrapper) {
Base = Addr.getOperand(0);
Offset = CurDAG->getTargetConstant(0, MVT::i32);
return true;
}
if (Addr.getOpcode() == ISD::ADD) {
ConstantSDNode *CN = 0;
if ((Addr.getOperand(0).getOpcode() == XCoreISD::DPRelativeWrapper)
&& (CN = dyn_cast<ConstantSDNode>(Addr.getOperand(1)))
&& (CN->getSExtValue() % 4 == 0 && CN->getSExtValue() >= 0)) {
// Constant word offset from a object in the data region
Base = Addr.getOperand(0).getOperand(0);
Offset = CurDAG->getTargetConstant(CN->getSExtValue(), MVT::i32);
return true;
}
}
return false;
}
bool XCoreDAGToDAGISel::SelectADDRcpii(SDValue Addr, SDValue &Base,
SDValue &Offset) {
if (Addr.getOpcode() == XCoreISD::CPRelativeWrapper) {
Base = Addr.getOperand(0);
Offset = CurDAG->getTargetConstant(0, MVT::i32);
return true;
}
if (Addr.getOpcode() == ISD::ADD) {
ConstantSDNode *CN = 0;
if ((Addr.getOperand(0).getOpcode() == XCoreISD::CPRelativeWrapper)
&& (CN = dyn_cast<ConstantSDNode>(Addr.getOperand(1)))
&& (CN->getSExtValue() % 4 == 0 && CN->getSExtValue() >= 0)) {
// Constant word offset from a object in the data region
Base = Addr.getOperand(0).getOperand(0);
Offset = CurDAG->getTargetConstant(CN->getSExtValue(), MVT::i32);
return true;
}
}
return false;
}
SDNode *XCoreDAGToDAGISel::Select(SDNode *N) {
DebugLoc dl = N->getDebugLoc();
switch (N->getOpcode()) {
default: break;
case ISD::Constant: {
uint64_t Val = cast<ConstantSDNode>(N)->getZExtValue();
if (immMskBitp(N)) {
// Transformation function: get the size of a mask
// Look for the first non-zero bit
SDValue MskSize = getI32Imm(32 - CountLeadingZeros_32(Val));
return CurDAG->getMachineNode(XCore::MKMSK_rus, dl,
MVT::i32, MskSize);
}
else if (!isUInt<16>(Val)) {
SDValue CPIdx =
CurDAG->getTargetConstantPool(ConstantInt::get(
Type::getInt32Ty(*CurDAG->getContext()), Val),
TLI.getPointerTy());
SDNode *node = CurDAG->getMachineNode(XCore::LDWCP_lru6, dl, MVT::i32,
MVT::Other, CPIdx,
CurDAG->getEntryNode());
MachineSDNode::mmo_iterator MemOp = MF->allocateMemRefsArray(1);
MemOp[0] = MF->getMachineMemOperand(
MachinePointerInfo::getConstantPool(), MachineMemOperand::MOLoad, 4, 4);
cast<MachineSDNode>(node)->setMemRefs(MemOp, MemOp + 1);
return node;
}
break;
}
case XCoreISD::LADD: {
SDValue Ops[] = { N->getOperand(0), N->getOperand(1),
N->getOperand(2) };
return CurDAG->getMachineNode(XCore::LADD_l5r, dl, MVT::i32, MVT::i32,
Ops, 3);
}
case XCoreISD::LSUB: {
SDValue Ops[] = { N->getOperand(0), N->getOperand(1),
N->getOperand(2) };
return CurDAG->getMachineNode(XCore::LSUB_l5r, dl, MVT::i32, MVT::i32,
Ops, 3);
}
case XCoreISD::MACCU: {
SDValue Ops[] = { N->getOperand(0), N->getOperand(1),
N->getOperand(2), N->getOperand(3) };
return CurDAG->getMachineNode(XCore::MACCU_l4r, dl, MVT::i32, MVT::i32,
Ops, 4);
}
case XCoreISD::MACCS: {
SDValue Ops[] = { N->getOperand(0), N->getOperand(1),
N->getOperand(2), N->getOperand(3) };
return CurDAG->getMachineNode(XCore::MACCS_l4r, dl, MVT::i32, MVT::i32,
Ops, 4);
}
case XCoreISD::LMUL: {
SDValue Ops[] = { N->getOperand(0), N->getOperand(1),
N->getOperand(2), N->getOperand(3) };
return CurDAG->getMachineNode(XCore::LMUL_l6r, dl, MVT::i32, MVT::i32,
Ops, 4);
}
case ISD::INTRINSIC_WO_CHAIN: {
unsigned IntNo = cast<ConstantSDNode>(N->getOperand(0))->getZExtValue();
switch (IntNo) {
case Intrinsic::xcore_crc8:
SDValue Ops[] = { N->getOperand(1), N->getOperand(2), N->getOperand(3) };
return CurDAG->getMachineNode(XCore::CRC8_l4r, dl, MVT::i32, MVT::i32,
Ops, 3);
}
break;
}
case ISD::BRIND:
if (SDNode *ResNode = SelectBRIND(N))
return ResNode;
break;
// Other cases are autogenerated.
}
return SelectCode(N);
}
/// Given a chain return a new chain where any appearance of Old is replaced
/// by New. There must be at most one instruction between Old and Chain and
/// this instruction must be a TokenFactor. Returns an empty SDValue if
/// these conditions don't hold.
static SDValue
replaceInChain(SelectionDAG *CurDAG, SDValue Chain, SDValue Old, SDValue New)
{
if (Chain == Old)
return New;
if (Chain->getOpcode() != ISD::TokenFactor)
return SDValue();
SmallVector<SDValue, 8> Ops;
bool found = false;
for (unsigned i = 0, e = Chain->getNumOperands(); i != e; ++i) {
if (Chain->getOperand(i) == Old) {
Ops.push_back(New);
found = true;
} else {
Ops.push_back(Chain->getOperand(i));
}
}
if (!found)
return SDValue();
return CurDAG->getNode(ISD::TokenFactor, Chain->getDebugLoc(), MVT::Other,
&Ops[0], Ops.size());
}
SDNode *XCoreDAGToDAGISel::SelectBRIND(SDNode *N) {
DebugLoc dl = N->getDebugLoc();
// (brind (int_xcore_checkevent (addr)))
SDValue Chain = N->getOperand(0);
SDValue Addr = N->getOperand(1);
if (Addr->getOpcode() != ISD::INTRINSIC_W_CHAIN)
return 0;
unsigned IntNo = cast<ConstantSDNode>(Addr->getOperand(1))->getZExtValue();
if (IntNo != Intrinsic::xcore_checkevent)
return 0;
SDValue nextAddr = Addr->getOperand(2);
SDValue CheckEventChainOut(Addr.getNode(), 1);
if (!CheckEventChainOut.use_empty()) {
// If the chain out of the checkevent intrinsic is an operand of the
// indirect branch or used in a TokenFactor which is the operand of the
// indirect branch then build a new chain which uses the chain coming into
// the checkevent intrinsic instead.
SDValue CheckEventChainIn = Addr->getOperand(0);
SDValue NewChain = replaceInChain(CurDAG, Chain, CheckEventChainOut,
CheckEventChainIn);
if (!NewChain.getNode())
return 0;
Chain = NewChain;
}
// Enable events on the thread using setsr 1 and then disable them immediately
// after with clrsr 1. If any resources owned by the thread are ready an event
// will be taken. If no resource is ready we branch to the address which was
// the operand to the checkevent intrinsic.
SDValue constOne = getI32Imm(1);
SDValue Glue =
SDValue(CurDAG->getMachineNode(XCore::SETSR_branch_u6, dl, MVT::Glue,
constOne, Chain), 0);
Glue =
SDValue(CurDAG->getMachineNode(XCore::CLRSR_branch_u6, dl, MVT::Glue,
constOne, Glue), 0);
if (nextAddr->getOpcode() == XCoreISD::PCRelativeWrapper &&
nextAddr->getOperand(0)->getOpcode() == ISD::TargetBlockAddress) {
return CurDAG->SelectNodeTo(N, XCore::BRFU_lu6, MVT::Other,
nextAddr->getOperand(0), Glue);
}
return CurDAG->SelectNodeTo(N, XCore::BAU_1r, MVT::Other, nextAddr, Glue);
}