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llvm-6502/utils/TableGen/FastISelEmitter.cpp
Jim Grosbach ff372dc18d Tidy up. Comment grammar. 
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@189618 91177308-0d34-0410-b5e6-96231b3b80d8
2013-08-29 22:41:43 +00:00

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//===- FastISelEmitter.cpp - Generate an instruction selector -------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This tablegen backend emits code for use by the "fast" instruction
// selection algorithm. See the comments at the top of
// lib/CodeGen/SelectionDAG/FastISel.cpp for background.
//
// This file scans through the target's tablegen instruction-info files
// and extracts instructions with obvious-looking patterns, and it emits
// code to look up these instructions by type and operator.
//
//===----------------------------------------------------------------------===//
#include "CodeGenDAGPatterns.h"
#include "llvm/ADT/SmallString.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
#include "llvm/TableGen/Error.h"
#include "llvm/TableGen/Record.h"
#include "llvm/TableGen/TableGenBackend.h"
using namespace llvm;
/// InstructionMemo - This class holds additional information about an
/// instruction needed to emit code for it.
///
namespace {
struct InstructionMemo {
std::string Name;
const CodeGenRegisterClass *RC;
std::string SubRegNo;
std::vector<std::string>* PhysRegs;
};
} // End anonymous namespace
/// ImmPredicateSet - This uniques predicates (represented as a string) and
/// gives them unique (small) integer ID's that start at 0.
namespace {
class ImmPredicateSet {
DenseMap<TreePattern *, unsigned> ImmIDs;
std::vector<TreePredicateFn> PredsByName;
public:
unsigned getIDFor(TreePredicateFn Pred) {
unsigned &Entry = ImmIDs[Pred.getOrigPatFragRecord()];
if (Entry == 0) {
PredsByName.push_back(Pred);
Entry = PredsByName.size();
}
return Entry-1;
}
const TreePredicateFn &getPredicate(unsigned i) {
assert(i < PredsByName.size());
return PredsByName[i];
}
typedef std::vector<TreePredicateFn>::const_iterator iterator;
iterator begin() const { return PredsByName.begin(); }
iterator end() const { return PredsByName.end(); }
};
} // End anonymous namespace
/// OperandsSignature - This class holds a description of a list of operand
/// types. It has utility methods for emitting text based on the operands.
///
namespace {
struct OperandsSignature {
class OpKind {
enum { OK_Reg, OK_FP, OK_Imm, OK_Invalid = -1 };
char Repr;
public:
OpKind() : Repr(OK_Invalid) {}
bool operator<(OpKind RHS) const { return Repr < RHS.Repr; }
bool operator==(OpKind RHS) const { return Repr == RHS.Repr; }
static OpKind getReg() { OpKind K; K.Repr = OK_Reg; return K; }
static OpKind getFP() { OpKind K; K.Repr = OK_FP; return K; }
static OpKind getImm(unsigned V) {
assert((unsigned)OK_Imm+V < 128 &&
"Too many integer predicates for the 'Repr' char");
OpKind K; K.Repr = OK_Imm+V; return K;
}
bool isReg() const { return Repr == OK_Reg; }
bool isFP() const { return Repr == OK_FP; }
bool isImm() const { return Repr >= OK_Imm; }
unsigned getImmCode() const { assert(isImm()); return Repr-OK_Imm; }
void printManglingSuffix(raw_ostream &OS, ImmPredicateSet &ImmPredicates,
bool StripImmCodes) const {
if (isReg())
OS << 'r';
else if (isFP())
OS << 'f';
else {
OS << 'i';
if (!StripImmCodes)
if (unsigned Code = getImmCode())
OS << "_" << ImmPredicates.getPredicate(Code-1).getFnName();
}
}
};
SmallVector<OpKind, 3> Operands;
bool operator<(const OperandsSignature &O) const {
return Operands < O.Operands;
}
bool operator==(const OperandsSignature &O) const {
return Operands == O.Operands;
}
bool empty() const { return Operands.empty(); }
bool hasAnyImmediateCodes() const {
for (unsigned i = 0, e = Operands.size(); i != e; ++i)
if (Operands[i].isImm() && Operands[i].getImmCode() != 0)
return true;
return false;
}
/// getWithoutImmCodes - Return a copy of this with any immediate codes forced
/// to zero.
OperandsSignature getWithoutImmCodes() const {
OperandsSignature Result;
for (unsigned i = 0, e = Operands.size(); i != e; ++i)
if (!Operands[i].isImm())
Result.Operands.push_back(Operands[i]);
else
Result.Operands.push_back(OpKind::getImm(0));
return Result;
}
void emitImmediatePredicate(raw_ostream &OS, ImmPredicateSet &ImmPredicates) {
bool EmittedAnything = false;
for (unsigned i = 0, e = Operands.size(); i != e; ++i) {
if (!Operands[i].isImm()) continue;
unsigned Code = Operands[i].getImmCode();
if (Code == 0) continue;
if (EmittedAnything)
OS << " &&\n ";
TreePredicateFn PredFn = ImmPredicates.getPredicate(Code-1);
// Emit the type check.
OS << "VT == "
<< getEnumName(PredFn.getOrigPatFragRecord()->getTree(0)->getType(0))
<< " && ";
OS << PredFn.getFnName() << "(imm" << i <<')';
EmittedAnything = true;
}
}
/// initialize - Examine the given pattern and initialize the contents
/// of the Operands array accordingly. Return true if all the operands
/// are supported, false otherwise.
///
bool initialize(TreePatternNode *InstPatNode, const CodeGenTarget &Target,
MVT::SimpleValueType VT,
ImmPredicateSet &ImmediatePredicates,
const CodeGenRegisterClass *OrigDstRC) {
if (InstPatNode->isLeaf())
return false;
if (InstPatNode->getOperator()->getName() == "imm") {
Operands.push_back(OpKind::getImm(0));
return true;
}
if (InstPatNode->getOperator()->getName() == "fpimm") {
Operands.push_back(OpKind::getFP());
return true;
}
const CodeGenRegisterClass *DstRC = 0;
for (unsigned i = 0, e = InstPatNode->getNumChildren(); i != e; ++i) {
TreePatternNode *Op = InstPatNode->getChild(i);
// Handle imm operands specially.
if (!Op->isLeaf() && Op->getOperator()->getName() == "imm") {
unsigned PredNo = 0;
if (!Op->getPredicateFns().empty()) {
TreePredicateFn PredFn = Op->getPredicateFns()[0];
// If there is more than one predicate weighing in on this operand
// then we don't handle it. This doesn't typically happen for
// immediates anyway.
if (Op->getPredicateFns().size() > 1 ||
!PredFn.isImmediatePattern())
return false;
// Ignore any instruction with 'FastIselShouldIgnore', these are
// not needed and just bloat the fast instruction selector. For
// example, X86 doesn't need to generate code to match ADD16ri8 since
// ADD16ri will do just fine.
Record *Rec = PredFn.getOrigPatFragRecord()->getRecord();
if (Rec->getValueAsBit("FastIselShouldIgnore"))
return false;
PredNo = ImmediatePredicates.getIDFor(PredFn)+1;
}
// Handle unmatched immediate sizes here.
//if (Op->getType(0) != VT)
// return false;
Operands.push_back(OpKind::getImm(PredNo));
continue;
}
// For now, filter out any operand with a predicate.
// For now, filter out any operand with multiple values.
if (!Op->getPredicateFns().empty() || Op->getNumTypes() != 1)
return false;
if (!Op->isLeaf()) {
if (Op->getOperator()->getName() == "fpimm") {
Operands.push_back(OpKind::getFP());
continue;
}
// For now, ignore other non-leaf nodes.
return false;
}
assert(Op->hasTypeSet(0) && "Type infererence not done?");
// For now, all the operands must have the same type (if they aren't
// immediates). Note that this causes us to reject variable sized shifts
// on X86.
if (Op->getType(0) != VT)
return false;
DefInit *OpDI = dyn_cast<DefInit>(Op->getLeafValue());
if (!OpDI)
return false;
Record *OpLeafRec = OpDI->getDef();
// For now, the only other thing we accept is register operands.
const CodeGenRegisterClass *RC = 0;
if (OpLeafRec->isSubClassOf("RegisterOperand"))
OpLeafRec = OpLeafRec->getValueAsDef("RegClass");
if (OpLeafRec->isSubClassOf("RegisterClass"))
RC = &Target.getRegisterClass(OpLeafRec);
else if (OpLeafRec->isSubClassOf("Register"))
RC = Target.getRegBank().getRegClassForRegister(OpLeafRec);
else if (OpLeafRec->isSubClassOf("ValueType")) {
RC = OrigDstRC;
} else
return false;
// For now, this needs to be a register class of some sort.
if (!RC)
return false;
// For now, all the operands must have the same register class or be
// a strict subclass of the destination.
if (DstRC) {
if (DstRC != RC && !DstRC->hasSubClass(RC))
return false;
} else
DstRC = RC;
Operands.push_back(OpKind::getReg());
}
return true;
}
void PrintParameters(raw_ostream &OS) const {
for (unsigned i = 0, e = Operands.size(); i != e; ++i) {
if (Operands[i].isReg()) {
OS << "unsigned Op" << i << ", bool Op" << i << "IsKill";
} else if (Operands[i].isImm()) {
OS << "uint64_t imm" << i;
} else if (Operands[i].isFP()) {
OS << "const ConstantFP *f" << i;
} else {
llvm_unreachable("Unknown operand kind!");
}
if (i + 1 != e)
OS << ", ";
}
}
void PrintArguments(raw_ostream &OS,
const std::vector<std::string> &PR) const {
assert(PR.size() == Operands.size());
bool PrintedArg = false;
for (unsigned i = 0, e = Operands.size(); i != e; ++i) {
if (PR[i] != "")
// Implicit physical register operand.
continue;
if (PrintedArg)
OS << ", ";
if (Operands[i].isReg()) {
OS << "Op" << i << ", Op" << i << "IsKill";
PrintedArg = true;
} else if (Operands[i].isImm()) {
OS << "imm" << i;
PrintedArg = true;
} else if (Operands[i].isFP()) {
OS << "f" << i;
PrintedArg = true;
} else {
llvm_unreachable("Unknown operand kind!");
}
}
}
void PrintArguments(raw_ostream &OS) const {
for (unsigned i = 0, e = Operands.size(); i != e; ++i) {
if (Operands[i].isReg()) {
OS << "Op" << i << ", Op" << i << "IsKill";
} else if (Operands[i].isImm()) {
OS << "imm" << i;
} else if (Operands[i].isFP()) {
OS << "f" << i;
} else {
llvm_unreachable("Unknown operand kind!");
}
if (i + 1 != e)
OS << ", ";
}
}
void PrintManglingSuffix(raw_ostream &OS, const std::vector<std::string> &PR,
ImmPredicateSet &ImmPredicates,
bool StripImmCodes = false) const {
for (unsigned i = 0, e = Operands.size(); i != e; ++i) {
if (PR[i] != "")
// Implicit physical register operand. e.g. Instruction::Mul expect to
// select to a binary op. On x86, mul may take a single operand with
// the other operand being implicit. We must emit something that looks
// like a binary instruction except for the very inner FastEmitInst_*
// call.
continue;
Operands[i].printManglingSuffix(OS, ImmPredicates, StripImmCodes);
}
}
void PrintManglingSuffix(raw_ostream &OS, ImmPredicateSet &ImmPredicates,
bool StripImmCodes = false) const {
for (unsigned i = 0, e = Operands.size(); i != e; ++i)
Operands[i].printManglingSuffix(OS, ImmPredicates, StripImmCodes);
}
};
} // End anonymous namespace
namespace {
class FastISelMap {
typedef std::map<std::string, InstructionMemo> PredMap;
typedef std::map<MVT::SimpleValueType, PredMap> RetPredMap;
typedef std::map<MVT::SimpleValueType, RetPredMap> TypeRetPredMap;
typedef std::map<std::string, TypeRetPredMap> OpcodeTypeRetPredMap;
typedef std::map<OperandsSignature, OpcodeTypeRetPredMap>
OperandsOpcodeTypeRetPredMap;
OperandsOpcodeTypeRetPredMap SimplePatterns;
std::map<OperandsSignature, std::vector<OperandsSignature> >
SignaturesWithConstantForms;
std::string InstNS;
ImmPredicateSet ImmediatePredicates;
public:
explicit FastISelMap(std::string InstNS);
void collectPatterns(CodeGenDAGPatterns &CGP);
void printImmediatePredicates(raw_ostream &OS);
void printFunctionDefinitions(raw_ostream &OS);
};
} // End anonymous namespace
static std::string getOpcodeName(Record *Op, CodeGenDAGPatterns &CGP) {
return CGP.getSDNodeInfo(Op).getEnumName();
}
static std::string getLegalCName(std::string OpName) {
std::string::size_type pos = OpName.find("::");
if (pos != std::string::npos)
OpName.replace(pos, 2, "_");
return OpName;
}
FastISelMap::FastISelMap(std::string instns)
: InstNS(instns) {
}
static std::string PhyRegForNode(TreePatternNode *Op,
const CodeGenTarget &Target) {
std::string PhysReg;
if (!Op->isLeaf())
return PhysReg;
Record *OpLeafRec = cast<DefInit>(Op->getLeafValue())->getDef();
if (!OpLeafRec->isSubClassOf("Register"))
return PhysReg;
PhysReg += cast<StringInit>(OpLeafRec->getValue("Namespace")->getValue())
->getValue();
PhysReg += "::";
PhysReg += Target.getRegBank().getReg(OpLeafRec)->getName();
return PhysReg;
}
void FastISelMap::collectPatterns(CodeGenDAGPatterns &CGP) {
const CodeGenTarget &Target = CGP.getTargetInfo();
// Determine the target's namespace name.
InstNS = Target.getInstNamespace() + "::";
assert(InstNS.size() > 2 && "Can't determine target-specific namespace!");
// Scan through all the patterns and record the simple ones.
for (CodeGenDAGPatterns::ptm_iterator I = CGP.ptm_begin(),
E = CGP.ptm_end(); I != E; ++I) {
const PatternToMatch &Pattern = *I;
// For now, just look at Instructions, so that we don't have to worry
// about emitting multiple instructions for a pattern.
TreePatternNode *Dst = Pattern.getDstPattern();
if (Dst->isLeaf()) continue;
Record *Op = Dst->getOperator();
if (!Op->isSubClassOf("Instruction"))
continue;
CodeGenInstruction &II = CGP.getTargetInfo().getInstruction(Op);
if (II.Operands.empty())
continue;
// For now, ignore multi-instruction patterns.
bool MultiInsts = false;
for (unsigned i = 0, e = Dst->getNumChildren(); i != e; ++i) {
TreePatternNode *ChildOp = Dst->getChild(i);
if (ChildOp->isLeaf())
continue;
if (ChildOp->getOperator()->isSubClassOf("Instruction")) {
MultiInsts = true;
break;
}
}
if (MultiInsts)
continue;
// For now, ignore instructions where the first operand is not an
// output register.
const CodeGenRegisterClass *DstRC = 0;
std::string SubRegNo;
if (Op->getName() != "EXTRACT_SUBREG") {
Record *Op0Rec = II.Operands[0].Rec;
if (Op0Rec->isSubClassOf("RegisterOperand"))
Op0Rec = Op0Rec->getValueAsDef("RegClass");
if (!Op0Rec->isSubClassOf("RegisterClass"))
continue;
DstRC = &Target.getRegisterClass(Op0Rec);
if (!DstRC)
continue;
} else {
// If this isn't a leaf, then continue since the register classes are
// a bit too complicated for now.
if (!Dst->getChild(1)->isLeaf()) continue;
DefInit *SR = dyn_cast<DefInit>(Dst->getChild(1)->getLeafValue());
if (SR)
SubRegNo = getQualifiedName(SR->getDef());
else
SubRegNo = Dst->getChild(1)->getLeafValue()->getAsString();
}
// Inspect the pattern.
TreePatternNode *InstPatNode = Pattern.getSrcPattern();
if (!InstPatNode) continue;
if (InstPatNode->isLeaf()) continue;
// Ignore multiple result nodes for now.
if (InstPatNode->getNumTypes() > 1) continue;
Record *InstPatOp = InstPatNode->getOperator();
std::string OpcodeName = getOpcodeName(InstPatOp, CGP);
MVT::SimpleValueType RetVT = MVT::isVoid;
if (InstPatNode->getNumTypes()) RetVT = InstPatNode->getType(0);
MVT::SimpleValueType VT = RetVT;
if (InstPatNode->getNumChildren()) {
assert(InstPatNode->getChild(0)->getNumTypes() == 1);
VT = InstPatNode->getChild(0)->getType(0);
}
// For now, filter out any instructions with predicates.
if (!InstPatNode->getPredicateFns().empty())
continue;
// Check all the operands.
OperandsSignature Operands;
if (!Operands.initialize(InstPatNode, Target, VT, ImmediatePredicates,
DstRC))
continue;
std::vector<std::string>* PhysRegInputs = new std::vector<std::string>();
if (InstPatNode->getOperator()->getName() == "imm" ||
InstPatNode->getOperator()->getName() == "fpimm")
PhysRegInputs->push_back("");
else {
// Compute the PhysRegs used by the given pattern, and check that
// the mapping from the src to dst patterns is simple.
bool FoundNonSimplePattern = false;
unsigned DstIndex = 0;
for (unsigned i = 0, e = InstPatNode->getNumChildren(); i != e; ++i) {
std::string PhysReg = PhyRegForNode(InstPatNode->getChild(i), Target);
if (PhysReg.empty()) {
if (DstIndex >= Dst->getNumChildren() ||
Dst->getChild(DstIndex)->getName() !=
InstPatNode->getChild(i)->getName()) {
FoundNonSimplePattern = true;
break;
}
++DstIndex;
}
PhysRegInputs->push_back(PhysReg);
}
if (Op->getName() != "EXTRACT_SUBREG" && DstIndex < Dst->getNumChildren())
FoundNonSimplePattern = true;
if (FoundNonSimplePattern)
continue;
}
// Get the predicate that guards this pattern.
std::string PredicateCheck = Pattern.getPredicateCheck();
// Ok, we found a pattern that we can handle. Remember it.
InstructionMemo Memo = {
Pattern.getDstPattern()->getOperator()->getName(),
DstRC,
SubRegNo,
PhysRegInputs
};
if (SimplePatterns[Operands][OpcodeName][VT][RetVT].count(PredicateCheck))
PrintFatalError(Pattern.getSrcRecord()->getLoc(),
"Duplicate record in FastISel table!");
SimplePatterns[Operands][OpcodeName][VT][RetVT][PredicateCheck] = Memo;
// If any of the operands were immediates with predicates on them, strip
// them down to a signature that doesn't have predicates so that we can
// associate them with the stripped predicate version.
if (Operands.hasAnyImmediateCodes()) {
SignaturesWithConstantForms[Operands.getWithoutImmCodes()]
.push_back(Operands);
}
}
}
void FastISelMap::printImmediatePredicates(raw_ostream &OS) {
if (ImmediatePredicates.begin() == ImmediatePredicates.end())
return;
OS << "\n// FastEmit Immediate Predicate functions.\n";
for (ImmPredicateSet::iterator I = ImmediatePredicates.begin(),
E = ImmediatePredicates.end(); I != E; ++I) {
OS << "static bool " << I->getFnName() << "(int64_t Imm) {\n";
OS << I->getImmediatePredicateCode() << "\n}\n";
}
OS << "\n\n";
}
void FastISelMap::printFunctionDefinitions(raw_ostream &OS) {
// Now emit code for all the patterns that we collected.
for (OperandsOpcodeTypeRetPredMap::const_iterator OI = SimplePatterns.begin(),
OE = SimplePatterns.end(); OI != OE; ++OI) {
const OperandsSignature &Operands = OI->first;
const OpcodeTypeRetPredMap &OTM = OI->second;
for (OpcodeTypeRetPredMap::const_iterator I = OTM.begin(), E = OTM.end();
I != E; ++I) {
const std::string &Opcode = I->first;
const TypeRetPredMap &TM = I->second;
OS << "// FastEmit functions for " << Opcode << ".\n";
OS << "\n";
// Emit one function for each opcode,type pair.
for (TypeRetPredMap::const_iterator TI = TM.begin(), TE = TM.end();
TI != TE; ++TI) {
MVT::SimpleValueType VT = TI->first;
const RetPredMap &RM = TI->second;
if (RM.size() != 1) {
for (RetPredMap::const_iterator RI = RM.begin(), RE = RM.end();
RI != RE; ++RI) {
MVT::SimpleValueType RetVT = RI->first;
const PredMap &PM = RI->second;
bool HasPred = false;
OS << "unsigned FastEmit_"
<< getLegalCName(Opcode)
<< "_" << getLegalCName(getName(VT))
<< "_" << getLegalCName(getName(RetVT)) << "_";
Operands.PrintManglingSuffix(OS, ImmediatePredicates);
OS << "(";
Operands.PrintParameters(OS);
OS << ") {\n";
// Emit code for each possible instruction. There may be
// multiple if there are subtarget concerns.
for (PredMap::const_iterator PI = PM.begin(), PE = PM.end();
PI != PE; ++PI) {
std::string PredicateCheck = PI->first;
const InstructionMemo &Memo = PI->second;
if (PredicateCheck.empty()) {
assert(!HasPred &&
"Multiple instructions match, at least one has "
"a predicate and at least one doesn't!");
} else {
OS << " if (" + PredicateCheck + ") {\n";
OS << " ";
HasPred = true;
}
for (unsigned i = 0; i < Memo.PhysRegs->size(); ++i) {
if ((*Memo.PhysRegs)[i] != "")
OS << " BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, "
<< "TII.get(TargetOpcode::COPY), "
<< (*Memo.PhysRegs)[i] << ").addReg(Op" << i << ");\n";
}
OS << " return FastEmitInst_";
if (Memo.SubRegNo.empty()) {
Operands.PrintManglingSuffix(OS, *Memo.PhysRegs,
ImmediatePredicates, true);
OS << "(" << InstNS << Memo.Name << ", ";
OS << "&" << InstNS << Memo.RC->getName() << "RegClass";
if (!Operands.empty())
OS << ", ";
Operands.PrintArguments(OS, *Memo.PhysRegs);
OS << ");\n";
} else {
OS << "extractsubreg(" << getName(RetVT);
OS << ", Op0, Op0IsKill, " << Memo.SubRegNo << ");\n";
}
if (HasPred)
OS << " }\n";
}
// Return 0 if none of the predicates were satisfied.
if (HasPred)
OS << " return 0;\n";
OS << "}\n";
OS << "\n";
}
// Emit one function for the type that demultiplexes on return type.
OS << "unsigned FastEmit_"
<< getLegalCName(Opcode) << "_"
<< getLegalCName(getName(VT)) << "_";
Operands.PrintManglingSuffix(OS, ImmediatePredicates);
OS << "(MVT RetVT";
if (!Operands.empty())
OS << ", ";
Operands.PrintParameters(OS);
OS << ") {\nswitch (RetVT.SimpleTy) {\n";
for (RetPredMap::const_iterator RI = RM.begin(), RE = RM.end();
RI != RE; ++RI) {
MVT::SimpleValueType RetVT = RI->first;
OS << " case " << getName(RetVT) << ": return FastEmit_"
<< getLegalCName(Opcode) << "_" << getLegalCName(getName(VT))
<< "_" << getLegalCName(getName(RetVT)) << "_";
Operands.PrintManglingSuffix(OS, ImmediatePredicates);
OS << "(";
Operands.PrintArguments(OS);
OS << ");\n";
}
OS << " default: return 0;\n}\n}\n\n";
} else {
// Non-variadic return type.
OS << "unsigned FastEmit_"
<< getLegalCName(Opcode) << "_"
<< getLegalCName(getName(VT)) << "_";
Operands.PrintManglingSuffix(OS, ImmediatePredicates);
OS << "(MVT RetVT";
if (!Operands.empty())
OS << ", ";
Operands.PrintParameters(OS);
OS << ") {\n";
OS << " if (RetVT.SimpleTy != " << getName(RM.begin()->first)
<< ")\n return 0;\n";
const PredMap &PM = RM.begin()->second;
bool HasPred = false;
// Emit code for each possible instruction. There may be
// multiple if there are subtarget concerns.
for (PredMap::const_iterator PI = PM.begin(), PE = PM.end(); PI != PE;
++PI) {
std::string PredicateCheck = PI->first;
const InstructionMemo &Memo = PI->second;
if (PredicateCheck.empty()) {
assert(!HasPred &&
"Multiple instructions match, at least one has "
"a predicate and at least one doesn't!");
} else {
OS << " if (" + PredicateCheck + ") {\n";
OS << " ";
HasPred = true;
}
for (unsigned i = 0; i < Memo.PhysRegs->size(); ++i) {
if ((*Memo.PhysRegs)[i] != "")
OS << " BuildMI(*FuncInfo.MBB, FuncInfo.InsertPt, DL, "
<< "TII.get(TargetOpcode::COPY), "
<< (*Memo.PhysRegs)[i] << ").addReg(Op" << i << ");\n";
}
OS << " return FastEmitInst_";
if (Memo.SubRegNo.empty()) {
Operands.PrintManglingSuffix(OS, *Memo.PhysRegs,
ImmediatePredicates, true);
OS << "(" << InstNS << Memo.Name << ", ";
OS << "&" << InstNS << Memo.RC->getName() << "RegClass";
if (!Operands.empty())
OS << ", ";
Operands.PrintArguments(OS, *Memo.PhysRegs);
OS << ");\n";
} else {
OS << "extractsubreg(RetVT, Op0, Op0IsKill, ";
OS << Memo.SubRegNo;
OS << ");\n";
}
if (HasPred)
OS << " }\n";
}
// Return 0 if none of the predicates were satisfied.
if (HasPred)
OS << " return 0;\n";
OS << "}\n";
OS << "\n";
}
}
// Emit one function for the opcode that demultiplexes based on the type.
OS << "unsigned FastEmit_"
<< getLegalCName(Opcode) << "_";
Operands.PrintManglingSuffix(OS, ImmediatePredicates);
OS << "(MVT VT, MVT RetVT";
if (!Operands.empty())
OS << ", ";
Operands.PrintParameters(OS);
OS << ") {\n";
OS << " switch (VT.SimpleTy) {\n";
for (TypeRetPredMap::const_iterator TI = TM.begin(), TE = TM.end();
TI != TE; ++TI) {
MVT::SimpleValueType VT = TI->first;
std::string TypeName = getName(VT);
OS << " case " << TypeName << ": return FastEmit_"
<< getLegalCName(Opcode) << "_" << getLegalCName(TypeName) << "_";
Operands.PrintManglingSuffix(OS, ImmediatePredicates);
OS << "(RetVT";
if (!Operands.empty())
OS << ", ";
Operands.PrintArguments(OS);
OS << ");\n";
}
OS << " default: return 0;\n";
OS << " }\n";
OS << "}\n";
OS << "\n";
}
OS << "// Top-level FastEmit function.\n";
OS << "\n";
// Emit one function for the operand signature that demultiplexes based
// on opcode and type.
OS << "unsigned FastEmit_";
Operands.PrintManglingSuffix(OS, ImmediatePredicates);
OS << "(MVT VT, MVT RetVT, unsigned Opcode";
if (!Operands.empty())
OS << ", ";
Operands.PrintParameters(OS);
OS << ") {\n";
// If there are any forms of this signature available that operate on
// constrained forms of the immediate (e.g., 32-bit sext immediate in a
// 64-bit operand), check them first.
std::map<OperandsSignature, std::vector<OperandsSignature> >::iterator MI
= SignaturesWithConstantForms.find(Operands);
if (MI != SignaturesWithConstantForms.end()) {
// Unique any duplicates out of the list.
std::sort(MI->second.begin(), MI->second.end());
MI->second.erase(std::unique(MI->second.begin(), MI->second.end()),
MI->second.end());
// Check each in order it was seen. It would be nice to have a good
// relative ordering between them, but we're not going for optimality
// here.
for (unsigned i = 0, e = MI->second.size(); i != e; ++i) {
OS << " if (";
MI->second[i].emitImmediatePredicate(OS, ImmediatePredicates);
OS << ")\n if (unsigned Reg = FastEmit_";
MI->second[i].PrintManglingSuffix(OS, ImmediatePredicates);
OS << "(VT, RetVT, Opcode";
if (!MI->second[i].empty())
OS << ", ";
MI->second[i].PrintArguments(OS);
OS << "))\n return Reg;\n\n";
}
// Done with this, remove it.
SignaturesWithConstantForms.erase(MI);
}
OS << " switch (Opcode) {\n";
for (OpcodeTypeRetPredMap::const_iterator I = OTM.begin(), E = OTM.end();
I != E; ++I) {
const std::string &Opcode = I->first;
OS << " case " << Opcode << ": return FastEmit_"
<< getLegalCName(Opcode) << "_";
Operands.PrintManglingSuffix(OS, ImmediatePredicates);
OS << "(VT, RetVT";
if (!Operands.empty())
OS << ", ";
Operands.PrintArguments(OS);
OS << ");\n";
}
OS << " default: return 0;\n";
OS << " }\n";
OS << "}\n";
OS << "\n";
}
// TODO: SignaturesWithConstantForms should be empty here.
}
namespace llvm {
void EmitFastISel(RecordKeeper &RK, raw_ostream &OS) {
CodeGenDAGPatterns CGP(RK);
const CodeGenTarget &Target = CGP.getTargetInfo();
emitSourceFileHeader("\"Fast\" Instruction Selector for the " +
Target.getName() + " target", OS);
// Determine the target's namespace name.
std::string InstNS = Target.getInstNamespace() + "::";
assert(InstNS.size() > 2 && "Can't determine target-specific namespace!");
FastISelMap F(InstNS);
F.collectPatterns(CGP);
F.printImmediatePredicates(OS);
F.printFunctionDefinitions(OS);
}
} // End llvm namespace
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