llvm-6502/lib/Target/MSP430/MSP430ISelDAGToDAG.cpp

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//===-- MSP430ISelDAGToDAG.cpp - A dag to dag inst selector for MSP430 ----===//
//
// 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 MSP430 target.
//
//===----------------------------------------------------------------------===//
#include "MSP430.h"
#include "MSP430TargetMachine.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/IR/CallingConv.h"
#include "llvm/IR/Constants.h"
#include "llvm/IR/DerivedTypes.h"
#include "llvm/IR/Function.h"
#include "llvm/IR/Intrinsics.h"
#include "llvm/Support/Compiler.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetLowering.h"
using namespace llvm;
[Modules] Make Support/Debug.h modular. This requires it to not change behavior based on other files defining DEBUG_TYPE, which means it cannot define DEBUG_TYPE at all. This is actually better IMO as it forces folks to define relevant DEBUG_TYPEs for their files. However, it requires all files that currently use DEBUG(...) to define a DEBUG_TYPE if they don't already. I've updated all such files in LLVM and will do the same for other upstream projects. This still leaves one important change in how LLVM uses the DEBUG_TYPE macro going forward: we need to only define the macro *after* header files have been #include-ed. Previously, this wasn't possible because Debug.h required the macro to be pre-defined. This commit removes that. By defining DEBUG_TYPE after the includes two things are fixed: - Header files that need to provide a DEBUG_TYPE for some inline code can do so by defining the macro before their inline code and undef-ing it afterward so the macro does not escape. - We no longer have rampant ODR violations due to including headers with different DEBUG_TYPE definitions. This may be mostly an academic violation today, but with modules these types of violations are easy to check for and potentially very relevant. Where necessary to suppor headers with DEBUG_TYPE, I have moved the definitions below the includes in this commit. I plan to move the rest of the DEBUG_TYPE macros in LLVM in subsequent commits; this one is big enough. The comments in Debug.h, which were hilariously out of date already, have been updated to reflect the recommended practice going forward. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@206822 91177308-0d34-0410-b5e6-96231b3b80d8
2014-04-21 22:55:11 +00:00
#define DEBUG_TYPE "msp430-isel"
namespace {
struct MSP430ISelAddressMode {
enum {
RegBase,
FrameIndexBase
} BaseType;
struct { // This is really a union, discriminated by BaseType!
SDValue Reg;
int FrameIndex;
} Base;
int16_t Disp;
const GlobalValue *GV;
const Constant *CP;
const BlockAddress *BlockAddr;
const char *ES;
int JT;
unsigned Align; // CP alignment.
MSP430ISelAddressMode()
: BaseType(RegBase), Disp(0), GV(nullptr), CP(nullptr),
BlockAddr(nullptr), ES(nullptr), JT(-1), Align(0) {
}
bool hasSymbolicDisplacement() const {
return GV != nullptr || CP != nullptr || ES != nullptr || JT != -1;
}
void dump() {
errs() << "MSP430ISelAddressMode " << this << '\n';
if (BaseType == RegBase && Base.Reg.getNode() != nullptr) {
errs() << "Base.Reg ";
Base.Reg.getNode()->dump();
} else if (BaseType == FrameIndexBase) {
errs() << " Base.FrameIndex " << Base.FrameIndex << '\n';
}
errs() << " Disp " << Disp << '\n';
if (GV) {
errs() << "GV ";
GV->dump();
} else if (CP) {
errs() << " CP ";
CP->dump();
errs() << " Align" << Align << '\n';
} else if (ES) {
errs() << "ES ";
errs() << ES << '\n';
} else if (JT != -1)
errs() << " JT" << JT << " Align" << Align << '\n';
}
};
}
/// MSP430DAGToDAGISel - MSP430 specific code to select MSP430 machine
/// instructions for SelectionDAG operations.
///
namespace {
class MSP430DAGToDAGISel : public SelectionDAGISel {
const MSP430TargetLowering &Lowering;
const MSP430Subtarget &Subtarget;
public:
MSP430DAGToDAGISel(MSP430TargetMachine &TM, CodeGenOpt::Level OptLevel)
: SelectionDAGISel(TM, OptLevel),
Lowering(*TM.getSubtargetImpl()->getTargetLowering()),
Subtarget(*TM.getSubtargetImpl()) {}
const char *getPassName() const override {
return "MSP430 DAG->DAG Pattern Instruction Selection";
}
bool MatchAddress(SDValue N, MSP430ISelAddressMode &AM);
bool MatchWrapper(SDValue N, MSP430ISelAddressMode &AM);
bool MatchAddressBase(SDValue N, MSP430ISelAddressMode &AM);
bool SelectInlineAsmMemoryOperand(const SDValue &Op, char ConstraintCode,
std::vector<SDValue> &OutOps) override;
// Include the pieces autogenerated from the target description.
#include "MSP430GenDAGISel.inc"
private:
SDNode *Select(SDNode *N) override;
SDNode *SelectIndexedLoad(SDNode *Op);
SDNode *SelectIndexedBinOp(SDNode *Op, SDValue N1, SDValue N2,
unsigned Opc8, unsigned Opc16);
bool SelectAddr(SDValue Addr, SDValue &Base, SDValue &Disp);
};
} // end anonymous namespace
/// createMSP430ISelDag - This pass converts a legalized DAG into a
/// MSP430-specific DAG, ready for instruction scheduling.
///
FunctionPass *llvm::createMSP430ISelDag(MSP430TargetMachine &TM,
CodeGenOpt::Level OptLevel) {
return new MSP430DAGToDAGISel(TM, OptLevel);
}
/// MatchWrapper - Try to match MSP430ISD::Wrapper node into an addressing mode.
/// These wrap things that will resolve down into a symbol reference. If no
/// match is possible, this returns true, otherwise it returns false.
bool MSP430DAGToDAGISel::MatchWrapper(SDValue N, MSP430ISelAddressMode &AM) {
// If the addressing mode already has a symbol as the displacement, we can
// never match another symbol.
if (AM.hasSymbolicDisplacement())
return true;
SDValue N0 = N.getOperand(0);
if (GlobalAddressSDNode *G = dyn_cast<GlobalAddressSDNode>(N0)) {
AM.GV = G->getGlobal();
AM.Disp += G->getOffset();
//AM.SymbolFlags = G->getTargetFlags();
} else if (ConstantPoolSDNode *CP = dyn_cast<ConstantPoolSDNode>(N0)) {
AM.CP = CP->getConstVal();
AM.Align = CP->getAlignment();
AM.Disp += CP->getOffset();
//AM.SymbolFlags = CP->getTargetFlags();
} else if (ExternalSymbolSDNode *S = dyn_cast<ExternalSymbolSDNode>(N0)) {
AM.ES = S->getSymbol();
//AM.SymbolFlags = S->getTargetFlags();
} else if (JumpTableSDNode *J = dyn_cast<JumpTableSDNode>(N0)) {
AM.JT = J->getIndex();
//AM.SymbolFlags = J->getTargetFlags();
} else {
AM.BlockAddr = cast<BlockAddressSDNode>(N0)->getBlockAddress();
//AM.SymbolFlags = cast<BlockAddressSDNode>(N0)->getTargetFlags();
}
return false;
}
/// MatchAddressBase - Helper for MatchAddress. Add the specified node to the
/// specified addressing mode without any further recursion.
bool MSP430DAGToDAGISel::MatchAddressBase(SDValue N, MSP430ISelAddressMode &AM) {
// Is the base register already occupied?
if (AM.BaseType != MSP430ISelAddressMode::RegBase || AM.Base.Reg.getNode()) {
// If so, we cannot select it.
return true;
}
// Default, generate it as a register.
AM.BaseType = MSP430ISelAddressMode::RegBase;
AM.Base.Reg = N;
return false;
}
bool MSP430DAGToDAGISel::MatchAddress(SDValue N, MSP430ISelAddressMode &AM) {
DEBUG(errs() << "MatchAddress: "; AM.dump());
switch (N.getOpcode()) {
default: break;
case ISD::Constant: {
uint64_t Val = cast<ConstantSDNode>(N)->getSExtValue();
AM.Disp += Val;
return false;
}
case MSP430ISD::Wrapper:
if (!MatchWrapper(N, AM))
return false;
break;
case ISD::FrameIndex:
if (AM.BaseType == MSP430ISelAddressMode::RegBase
&& AM.Base.Reg.getNode() == nullptr) {
AM.BaseType = MSP430ISelAddressMode::FrameIndexBase;
AM.Base.FrameIndex = cast<FrameIndexSDNode>(N)->getIndex();
return false;
}
break;
case ISD::ADD: {
MSP430ISelAddressMode Backup = AM;
if (!MatchAddress(N.getNode()->getOperand(0), AM) &&
!MatchAddress(N.getNode()->getOperand(1), AM))
return false;
AM = Backup;
if (!MatchAddress(N.getNode()->getOperand(1), AM) &&
!MatchAddress(N.getNode()->getOperand(0), AM))
return false;
AM = Backup;
break;
}
case ISD::OR:
// Handle "X | C" as "X + C" iff X is known to have C bits clear.
if (ConstantSDNode *CN = dyn_cast<ConstantSDNode>(N.getOperand(1))) {
MSP430ISelAddressMode Backup = AM;
uint64_t Offset = CN->getSExtValue();
// Start with the LHS as an addr mode.
if (!MatchAddress(N.getOperand(0), AM) &&
// Address could not have picked a GV address for the displacement.
AM.GV == nullptr &&
// Check to see if the LHS & C is zero.
CurDAG->MaskedValueIsZero(N.getOperand(0), CN->getAPIntValue())) {
AM.Disp += Offset;
return false;
}
AM = Backup;
}
break;
}
return MatchAddressBase(N, AM);
}
/// SelectAddr - returns true if it is able pattern match an addressing mode.
/// It returns the operands which make up the maximal addressing mode it can
/// match by reference.
bool MSP430DAGToDAGISel::SelectAddr(SDValue N,
SDValue &Base, SDValue &Disp) {
MSP430ISelAddressMode AM;
if (MatchAddress(N, AM))
return false;
EVT VT = N.getValueType();
if (AM.BaseType == MSP430ISelAddressMode::RegBase) {
if (!AM.Base.Reg.getNode())
AM.Base.Reg = CurDAG->getRegister(0, VT);
}
Base = (AM.BaseType == MSP430ISelAddressMode::FrameIndexBase) ?
CurDAG->getTargetFrameIndex(AM.Base.FrameIndex,
getTargetLowering()->getPointerTy()) :
AM.Base.Reg;
if (AM.GV)
Disp = CurDAG->getTargetGlobalAddress(AM.GV, SDLoc(N),
MVT::i16, AM.Disp,
0/*AM.SymbolFlags*/);
else if (AM.CP)
Disp = CurDAG->getTargetConstantPool(AM.CP, MVT::i16,
AM.Align, AM.Disp, 0/*AM.SymbolFlags*/);
else if (AM.ES)
Disp = CurDAG->getTargetExternalSymbol(AM.ES, MVT::i16, 0/*AM.SymbolFlags*/);
else if (AM.JT != -1)
Disp = CurDAG->getTargetJumpTable(AM.JT, MVT::i16, 0/*AM.SymbolFlags*/);
else if (AM.BlockAddr)
Disp = CurDAG->getTargetBlockAddress(AM.BlockAddr, MVT::i32, 0,
0/*AM.SymbolFlags*/);
else
Disp = CurDAG->getTargetConstant(AM.Disp, MVT::i16);
return true;
}
bool MSP430DAGToDAGISel::
SelectInlineAsmMemoryOperand(const SDValue &Op, char ConstraintCode,
std::vector<SDValue> &OutOps) {
SDValue Op0, Op1;
switch (ConstraintCode) {
default: return true;
case 'm': // memory
if (!SelectAddr(Op, Op0, Op1))
return true;
break;
}
OutOps.push_back(Op0);
OutOps.push_back(Op1);
return false;
}
static bool isValidIndexedLoad(const LoadSDNode *LD) {
ISD::MemIndexedMode AM = LD->getAddressingMode();
if (AM != ISD::POST_INC || LD->getExtensionType() != ISD::NON_EXTLOAD)
return false;
EVT VT = LD->getMemoryVT();
switch (VT.getSimpleVT().SimpleTy) {
case MVT::i8:
// Sanity check
if (cast<ConstantSDNode>(LD->getOffset())->getZExtValue() != 1)
return false;
break;
case MVT::i16:
// Sanity check
if (cast<ConstantSDNode>(LD->getOffset())->getZExtValue() != 2)
return false;
break;
default:
return false;
}
return true;
}
SDNode *MSP430DAGToDAGISel::SelectIndexedLoad(SDNode *N) {
LoadSDNode *LD = cast<LoadSDNode>(N);
if (!isValidIndexedLoad(LD))
return nullptr;
MVT VT = LD->getMemoryVT().getSimpleVT();
unsigned Opcode = 0;
switch (VT.SimpleTy) {
case MVT::i8:
Opcode = MSP430::MOV8rm_POST;
break;
case MVT::i16:
Opcode = MSP430::MOV16rm_POST;
break;
default:
return nullptr;
}
return CurDAG->getMachineNode(Opcode, SDLoc(N),
VT, MVT::i16, MVT::Other,
LD->getBasePtr(), LD->getChain());
}
SDNode *MSP430DAGToDAGISel::SelectIndexedBinOp(SDNode *Op,
SDValue N1, SDValue N2,
unsigned Opc8, unsigned Opc16) {
if (N1.getOpcode() == ISD::LOAD &&
N1.hasOneUse() &&
IsLegalToFold(N1, Op, Op, OptLevel)) {
LoadSDNode *LD = cast<LoadSDNode>(N1);
if (!isValidIndexedLoad(LD))
return nullptr;
MVT VT = LD->getMemoryVT().getSimpleVT();
unsigned Opc = (VT == MVT::i16 ? Opc16 : Opc8);
MachineSDNode::mmo_iterator MemRefs0 = MF->allocateMemRefsArray(1);
MemRefs0[0] = cast<MemSDNode>(N1)->getMemOperand();
SDValue Ops0[] = { N2, LD->getBasePtr(), LD->getChain() };
SDNode *ResNode =
CurDAG->SelectNodeTo(Op, Opc, VT, MVT::i16, MVT::Other, Ops0);
cast<MachineSDNode>(ResNode)->setMemRefs(MemRefs0, MemRefs0 + 1);
// Transfer chain.
ReplaceUses(SDValue(N1.getNode(), 2), SDValue(ResNode, 2));
// Transfer writeback.
ReplaceUses(SDValue(N1.getNode(), 1), SDValue(ResNode, 1));
return ResNode;
}
return nullptr;
}
SDNode *MSP430DAGToDAGISel::Select(SDNode *Node) {
SDLoc dl(Node);
// Dump information about the Node being selected
DEBUG(errs() << "Selecting: ");
DEBUG(Node->dump(CurDAG));
DEBUG(errs() << "\n");
// If we have a custom node, we already have selected!
if (Node->isMachineOpcode()) {
DEBUG(errs() << "== ";
Node->dump(CurDAG);
errs() << "\n");
Node->setNodeId(-1);
return nullptr;
}
// Few custom selection stuff.
switch (Node->getOpcode()) {
default: break;
case ISD::FrameIndex: {
assert(Node->getValueType(0) == MVT::i16);
int FI = cast<FrameIndexSDNode>(Node)->getIndex();
SDValue TFI = CurDAG->getTargetFrameIndex(FI, MVT::i16);
if (Node->hasOneUse())
return CurDAG->SelectNodeTo(Node, MSP430::ADD16ri, MVT::i16,
TFI, CurDAG->getTargetConstant(0, MVT::i16));
return CurDAG->getMachineNode(MSP430::ADD16ri, dl, MVT::i16,
TFI, CurDAG->getTargetConstant(0, MVT::i16));
}
case ISD::LOAD:
if (SDNode *ResNode = SelectIndexedLoad(Node))
return ResNode;
// Other cases are autogenerated.
break;
case ISD::ADD:
if (SDNode *ResNode =
SelectIndexedBinOp(Node,
Node->getOperand(0), Node->getOperand(1),
MSP430::ADD8rm_POST, MSP430::ADD16rm_POST))
return ResNode;
else if (SDNode *ResNode =
SelectIndexedBinOp(Node, Node->getOperand(1), Node->getOperand(0),
MSP430::ADD8rm_POST, MSP430::ADD16rm_POST))
return ResNode;
// Other cases are autogenerated.
break;
case ISD::SUB:
if (SDNode *ResNode =
SelectIndexedBinOp(Node,
Node->getOperand(0), Node->getOperand(1),
MSP430::SUB8rm_POST, MSP430::SUB16rm_POST))
return ResNode;
// Other cases are autogenerated.
break;
case ISD::AND:
if (SDNode *ResNode =
SelectIndexedBinOp(Node,
Node->getOperand(0), Node->getOperand(1),
MSP430::AND8rm_POST, MSP430::AND16rm_POST))
return ResNode;
else if (SDNode *ResNode =
SelectIndexedBinOp(Node, Node->getOperand(1), Node->getOperand(0),
MSP430::AND8rm_POST, MSP430::AND16rm_POST))
return ResNode;
// Other cases are autogenerated.
break;
case ISD::OR:
if (SDNode *ResNode =
SelectIndexedBinOp(Node,
Node->getOperand(0), Node->getOperand(1),
MSP430::OR8rm_POST, MSP430::OR16rm_POST))
return ResNode;
else if (SDNode *ResNode =
SelectIndexedBinOp(Node, Node->getOperand(1), Node->getOperand(0),
MSP430::OR8rm_POST, MSP430::OR16rm_POST))
return ResNode;
// Other cases are autogenerated.
break;
case ISD::XOR:
if (SDNode *ResNode =
SelectIndexedBinOp(Node,
Node->getOperand(0), Node->getOperand(1),
MSP430::XOR8rm_POST, MSP430::XOR16rm_POST))
return ResNode;
else if (SDNode *ResNode =
SelectIndexedBinOp(Node, Node->getOperand(1), Node->getOperand(0),
MSP430::XOR8rm_POST, MSP430::XOR16rm_POST))
return ResNode;
// Other cases are autogenerated.
break;
}
// Select the default instruction
SDNode *ResNode = SelectCode(Node);
DEBUG(errs() << "=> ");
if (ResNode == nullptr || ResNode == Node)
DEBUG(Node->dump(CurDAG));
else
DEBUG(ResNode->dump(CurDAG));
DEBUG(errs() << "\n");
return ResNode;
}