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llvm-project/llvm/utils/TableGen/X86FoldTablesEmitter.cpp

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//===- utils/TableGen/X86FoldTablesEmitter.cpp - X86 backend-*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This tablegen backend is responsible for emitting the memory fold tables of
// the X86 backend instructions.
//
//===----------------------------------------------------------------------===//
#include "CodeGenTarget.h"
#include "X86RecognizableInstr.h"
#include "llvm/TableGen/Error.h"
#include "llvm/TableGen/TableGenBackend.h"
using namespace llvm;
namespace {
// 3 possible strategies for the unfolding flag (TB_NO_REVERSE) of the
// manual added entries.
enum UnfoldStrategy {
UNFOLD, // Allow unfolding
NO_UNFOLD, // Prevent unfolding
NO_STRATEGY // Make decision according to operands' sizes
};
// Represents an entry in the manual mapped instructions set.
struct ManualMapEntry {
const char *RegInstStr;
const char *MemInstStr;
UnfoldStrategy Strategy;
ManualMapEntry(const char *RegInstStr, const char *MemInstStr,
UnfoldStrategy Strategy = NO_STRATEGY)
: RegInstStr(RegInstStr), MemInstStr(MemInstStr), Strategy(Strategy) {}
};
class IsMatch;
// List of instructions requiring explicitly aligned memory.
const char *ExplicitAlign[] = {"MOVDQA", "MOVAPS", "MOVAPD", "MOVNTPS",
"MOVNTPD", "MOVNTDQ", "MOVNTDQA"};
// List of instructions NOT requiring explicit memory alignment.
const char *ExplicitUnalign[] = {"MOVDQU", "MOVUPS", "MOVUPD"};
// For manually mapping instructions that do not match by their encoding.
const ManualMapEntry ManualMapSet[] = {
{ "ADD16ri_DB", "ADD16mi", NO_UNFOLD },
{ "ADD16ri8_DB", "ADD16mi8", NO_UNFOLD },
{ "ADD16rr_DB", "ADD16mr", NO_UNFOLD },
{ "ADD32ri_DB", "ADD32mi", NO_UNFOLD },
{ "ADD32ri8_DB", "ADD32mi8", NO_UNFOLD },
{ "ADD32rr_DB", "ADD32mr", NO_UNFOLD },
{ "ADD64ri32_DB", "ADD64mi32", NO_UNFOLD },
{ "ADD64ri8_DB", "ADD64mi8", NO_UNFOLD },
{ "ADD64rr_DB", "ADD64mr", NO_UNFOLD },
{ "ADD16rr_DB", "ADD16rm", NO_UNFOLD },
{ "ADD32rr_DB", "ADD32rm", NO_UNFOLD },
{ "ADD64rr_DB", "ADD64rm", NO_UNFOLD },
{ "PUSH16r", "PUSH16rmm", NO_UNFOLD },
{ "PUSH32r", "PUSH32rmm", NO_UNFOLD },
{ "PUSH64r", "PUSH64rmm", NO_UNFOLD },
{ "TAILJMPr", "TAILJMPm", UNFOLD },
{ "TAILJMPr64", "TAILJMPm64", UNFOLD },
{ "TAILJMPr64_REX", "TAILJMPm64_REX", UNFOLD },
};
static bool isExplicitAlign(const CodeGenInstruction *Inst) {
return any_of(ExplicitAlign, [Inst](const char *InstStr) {
return Inst->TheDef->getName().find(InstStr) != StringRef::npos;
});
}
static bool isExplicitUnalign(const CodeGenInstruction *Inst) {
return any_of(ExplicitUnalign, [Inst](const char *InstStr) {
return Inst->TheDef->getName().find(InstStr) != StringRef::npos;
});
}
class X86FoldTablesEmitter {
RecordKeeper &Records;
CodeGenTarget Target;
// Represents an entry in the folding table
class X86FoldTableEntry {
const CodeGenInstruction *RegInst;
const CodeGenInstruction *MemInst;
public:
bool CannotUnfold = false;
bool IsLoad = false;
bool IsStore = false;
bool IsAligned = false;
unsigned int Alignment = 0;
X86FoldTableEntry(const CodeGenInstruction *RegInst,
const CodeGenInstruction *MemInst)
: RegInst(RegInst), MemInst(MemInst) {}
friend raw_ostream &operator<<(raw_ostream &OS,
const X86FoldTableEntry &E) {
OS << "{ X86::" << E.RegInst->TheDef->getName().str()
<< ", X86::" << E.MemInst->TheDef->getName().str() << ", ";
if (E.IsLoad)
OS << "TB_FOLDED_LOAD | ";
if (E.IsStore)
OS << "TB_FOLDED_STORE | ";
if (E.CannotUnfold)
OS << "TB_NO_REVERSE | ";
if (E.IsAligned)
OS << "TB_ALIGN_" << E.Alignment << " | ";
OS << "0 },\n";
return OS;
}
};
typedef std::vector<X86FoldTableEntry> FoldTable;
// std::vector for each folding table.
// Table2Addr - Holds instructions which their memory form performs load+store
// Table#i - Holds instructions which the their memory form perform a load OR
// a store, and their #i'th operand is folded.
FoldTable Table2Addr;
FoldTable Table0;
FoldTable Table1;
FoldTable Table2;
FoldTable Table3;
FoldTable Table4;
public:
X86FoldTablesEmitter(RecordKeeper &R) : Records(R), Target(R) {}
// run - Generate the 6 X86 memory fold tables.
void run(raw_ostream &OS);
private:
// Decides to which table to add the entry with the given instructions.
// S sets the strategy of adding the TB_NO_REVERSE flag.
void updateTables(const CodeGenInstruction *RegInstr,
const CodeGenInstruction *MemInstr,
const UnfoldStrategy S = NO_STRATEGY);
// Generates X86FoldTableEntry with the given instructions and fill it with
// the appropriate flags - then adds it to Table.
void addEntryWithFlags(FoldTable &Table, const CodeGenInstruction *RegInstr,
const CodeGenInstruction *MemInstr,
const UnfoldStrategy S, const unsigned int FoldedInd);
// Print the given table as a static const C++ array of type
// X86MemoryFoldTableEntry.
void printTable(const FoldTable &Table, std::string TableName,
raw_ostream &OS) {
OS << "static const X86MemoryFoldTableEntry MemoryFold" << TableName
<< "[] = {\n";
for (const X86FoldTableEntry &E : Table)
OS << E;
OS << "};\n";
}
};
// Return true if one of the instruction's operands is a RST register class
static bool hasRSTRegClass(const CodeGenInstruction *Inst) {
return any_of(Inst->Operands, [](const CGIOperandList::OperandInfo &OpIn) {
return OpIn.Rec->getName() == "RST";
});
}
// Return true if one of the instruction's operands is a ptr_rc_tailcall
static bool hasPtrTailcallRegClass(const CodeGenInstruction *Inst) {
return any_of(Inst->Operands, [](const CGIOperandList::OperandInfo &OpIn) {
return OpIn.Rec->getName() == "ptr_rc_tailcall";
});
}
// Calculates the integer value representing the BitsInit object
static inline uint64_t getValueFromBitsInit(const BitsInit *B) {
assert(B->getNumBits() <= sizeof(uint64_t) * 8 && "BitInits' too long!");
uint64_t Value = 0;
for (unsigned i = 0, e = B->getNumBits(); i != e; ++i) {
BitInit *Bit = cast<BitInit>(B->getBit(i));
Value |= uint64_t(Bit->getValue()) << i;
}
return Value;
}
// Returns true if the two given BitsInits represent the same integer value
static inline bool equalBitsInits(const BitsInit *B1, const BitsInit *B2) {
if (B1->getNumBits() != B2->getNumBits())
PrintFatalError("Comparing two BitsInits with different sizes!");
for (unsigned i = 0, e = B1->getNumBits(); i != e; ++i) {
BitInit *Bit1 = cast<BitInit>(B1->getBit(i));
BitInit *Bit2 = cast<BitInit>(B2->getBit(i));
if (Bit1->getValue() != Bit2->getValue())
return false;
}
return true;
}
// Return the size of the register operand
static inline unsigned int getRegOperandSize(const Record *RegRec) {
if (RegRec->isSubClassOf("RegisterOperand"))
RegRec = RegRec->getValueAsDef("RegClass");
if (RegRec->isSubClassOf("RegisterClass"))
return RegRec->getValueAsListOfDefs("RegTypes")[0]->getValueAsInt("Size");
llvm_unreachable("Register operand's size not known!");
}
// Return the size of the memory operand
static inline unsigned int
getMemOperandSize(const Record *MemRec, const bool IntrinsicSensitive = false) {
if (MemRec->isSubClassOf("Operand")) {
// Intrinsic memory instructions use ssmem/sdmem.
if (IntrinsicSensitive &&
(MemRec->getName() == "sdmem" || MemRec->getName() == "ssmem"))
return 128;
StringRef Name =
MemRec->getValueAsDef("ParserMatchClass")->getValueAsString("Name");
if (Name == "Mem8")
return 8;
if (Name == "Mem16")
return 16;
if (Name == "Mem32")
return 32;
if (Name == "Mem64")
return 64;
if (Name == "Mem80")
return 80;
if (Name == "Mem128")
return 128;
if (Name == "Mem256")
return 256;
if (Name == "Mem512")
return 512;
}
llvm_unreachable("Memory operand's size not known!");
}
// Returns true if the record's list of defs includes the given def.
static inline bool hasDefInList(const Record *Rec, const StringRef List,
const StringRef Def) {
if (!Rec->isValueUnset(List)) {
return any_of(*(Rec->getValueAsListInit(List)),
[Def](const Init *I) { return I->getAsString() == Def; });
}
return false;
}
// Return true if the instruction defined as a register flavor.
static inline bool hasRegisterFormat(const Record *Inst) {
const BitsInit *FormBits = Inst->getValueAsBitsInit("FormBits");
uint64_t FormBitsNum = getValueFromBitsInit(FormBits);
// Values from X86Local namespace defined in X86RecognizableInstr.cpp
return FormBitsNum >= X86Local::MRMDestReg && FormBitsNum <= X86Local::MRM7r;
}
// Return true if the instruction defined as a memory flavor.
static inline bool hasMemoryFormat(const Record *Inst) {
const BitsInit *FormBits = Inst->getValueAsBitsInit("FormBits");
uint64_t FormBitsNum = getValueFromBitsInit(FormBits);
// Values from X86Local namespace defined in X86RecognizableInstr.cpp
return FormBitsNum >= X86Local::MRMDestMem && FormBitsNum <= X86Local::MRM7m;
}
static inline bool isNOREXRegClass(const Record *Op) {
return Op->getName().find("_NOREX") != StringRef::npos;
}
static inline bool isRegisterOperand(const Record *Rec) {
return Rec->isSubClassOf("RegisterClass") ||
Rec->isSubClassOf("RegisterOperand") ||
Rec->isSubClassOf("PointerLikeRegClass");
}
static inline bool isMemoryOperand(const Record *Rec) {
return Rec->isSubClassOf("Operand") &&
Rec->getValueAsString("OperandType") == "OPERAND_MEMORY";
}
static inline bool isImmediateOperand(const Record *Rec) {
return Rec->isSubClassOf("Operand") &&
Rec->getValueAsString("OperandType") == "OPERAND_IMMEDIATE";
}
// Get the alternative instruction pointed by "FoldGenRegForm" field.
static inline const CodeGenInstruction *
getAltRegInst(const CodeGenInstruction *I, const RecordKeeper &Records,
const CodeGenTarget &Target) {
StringRef AltRegInstStr = I->TheDef->getValueAsString("FoldGenRegForm");
Record *AltRegInstRec = Records.getDef(AltRegInstStr);
assert(AltRegInstRec &&
"Alternative register form instruction def not found");
CodeGenInstruction &AltRegInst = Target.getInstruction(AltRegInstRec);
return &AltRegInst;
}
// Function object - Operator() returns true if the given VEX instruction
// matches the EVEX instruction of this object.
class IsMatch {
const CodeGenInstruction *MemInst;
public:
IsMatch(const CodeGenInstruction *Inst, const RecordKeeper &Records)
: MemInst(Inst) {}
bool operator()(const CodeGenInstruction *RegInst) {
Record *MemRec = MemInst->TheDef;
Record *RegRec = RegInst->TheDef;
// Return false if one (at least) of the encoding fields of both
// instructions do not match.
if (RegRec->getValueAsDef("OpEnc") != MemRec->getValueAsDef("OpEnc") ||
!equalBitsInits(RegRec->getValueAsBitsInit("Opcode"),
MemRec->getValueAsBitsInit("Opcode")) ||
// VEX/EVEX fields
RegRec->getValueAsDef("OpPrefix") !=
MemRec->getValueAsDef("OpPrefix") ||
RegRec->getValueAsDef("OpMap") != MemRec->getValueAsDef("OpMap") ||
RegRec->getValueAsDef("OpSize") != MemRec->getValueAsDef("OpSize") ||
RegRec->getValueAsBit("hasVEX_4V") !=
MemRec->getValueAsBit("hasVEX_4V") ||
RegRec->getValueAsBit("hasEVEX_K") !=
MemRec->getValueAsBit("hasEVEX_K") ||
RegRec->getValueAsBit("hasEVEX_Z") !=
MemRec->getValueAsBit("hasEVEX_Z") ||
// EVEX_B means different things for memory and register forms.
RegRec->getValueAsBit("hasEVEX_B") != 0 ||
MemRec->getValueAsBit("hasEVEX_B") != 0 ||
RegRec->getValueAsBit("hasEVEX_RC") !=
MemRec->getValueAsBit("hasEVEX_RC") ||
RegRec->getValueAsBit("hasREX_WPrefix") !=
MemRec->getValueAsBit("hasREX_WPrefix") ||
RegRec->getValueAsBit("hasLockPrefix") !=
MemRec->getValueAsBit("hasLockPrefix") ||
RegRec->getValueAsBit("hasNoTrackPrefix") !=
MemRec->getValueAsBit("hasNoTrackPrefix") ||
!equalBitsInits(RegRec->getValueAsBitsInit("EVEX_LL"),
MemRec->getValueAsBitsInit("EVEX_LL")) ||
!equalBitsInits(RegRec->getValueAsBitsInit("VEX_WPrefix"),
MemRec->getValueAsBitsInit("VEX_WPrefix")) ||
// Instruction's format - The register form's "Form" field should be
// the opposite of the memory form's "Form" field.
!areOppositeForms(RegRec->getValueAsBitsInit("FormBits"),
MemRec->getValueAsBitsInit("FormBits")) ||
RegRec->getValueAsBit("isAsmParserOnly") !=
MemRec->getValueAsBit("isAsmParserOnly"))
return false;
// Make sure the sizes of the operands of both instructions suit each other.
// This is needed for instructions with intrinsic version (_Int).
// Where the only difference is the size of the operands.
// For example: VUCOMISDZrm and Int_VUCOMISDrm
// Also for instructions that their EVEX version was upgraded to work with
// k-registers. For example VPCMPEQBrm (xmm output register) and
// VPCMPEQBZ128rm (k register output register).
bool ArgFolded = false;
unsigned MemOutSize = MemRec->getValueAsDag("OutOperandList")->getNumArgs();
unsigned RegOutSize = RegRec->getValueAsDag("OutOperandList")->getNumArgs();
unsigned MemInSize = MemRec->getValueAsDag("InOperandList")->getNumArgs();
unsigned RegInSize = RegRec->getValueAsDag("InOperandList")->getNumArgs();
// Instructions with one output in their memory form use the memory folded
// operand as source and destination (Read-Modify-Write).
unsigned RegStartIdx =
(MemOutSize + 1 == RegOutSize) && (MemInSize == RegInSize) ? 1 : 0;
for (unsigned i = 0, e = MemInst->Operands.size(); i < e; i++) {
Record *MemOpRec = MemInst->Operands[i].Rec;
Record *RegOpRec = RegInst->Operands[i + RegStartIdx].Rec;
if (MemOpRec == RegOpRec)
continue;
if (isRegisterOperand(MemOpRec) && isRegisterOperand(RegOpRec)) {
if (getRegOperandSize(MemOpRec) != getRegOperandSize(RegOpRec) ||
isNOREXRegClass(MemOpRec) != isNOREXRegClass(RegOpRec))
return false;
} else if (isMemoryOperand(MemOpRec) && isMemoryOperand(RegOpRec)) {
if (getMemOperandSize(MemOpRec) != getMemOperandSize(RegOpRec))
return false;
} else if (isImmediateOperand(MemOpRec) && isImmediateOperand(RegOpRec)) {
if (MemOpRec->getValueAsDef("Type") != RegOpRec->getValueAsDef("Type"))
return false;
} else {
// Only one operand can be folded.
if (ArgFolded)
return false;
assert(isRegisterOperand(RegOpRec) && isMemoryOperand(MemOpRec));
ArgFolded = true;
}
}
return true;
}
private:
// Return true of the 2 given forms are the opposite of each other.
bool areOppositeForms(const BitsInit *RegFormBits,
const BitsInit *MemFormBits) {
uint64_t MemFormNum = getValueFromBitsInit(MemFormBits);
uint64_t RegFormNum = getValueFromBitsInit(RegFormBits);
if ((MemFormNum == X86Local::MRM0m && RegFormNum == X86Local::MRM0r) ||
(MemFormNum == X86Local::MRM1m && RegFormNum == X86Local::MRM1r) ||
(MemFormNum == X86Local::MRM2m && RegFormNum == X86Local::MRM2r) ||
(MemFormNum == X86Local::MRM3m && RegFormNum == X86Local::MRM3r) ||
(MemFormNum == X86Local::MRM4m && RegFormNum == X86Local::MRM4r) ||
(MemFormNum == X86Local::MRM5m && RegFormNum == X86Local::MRM5r) ||
(MemFormNum == X86Local::MRM6m && RegFormNum == X86Local::MRM6r) ||
(MemFormNum == X86Local::MRM7m && RegFormNum == X86Local::MRM7r) ||
(MemFormNum == X86Local::MRMXm && RegFormNum == X86Local::MRMXr) ||
(MemFormNum == X86Local::MRMDestMem &&
RegFormNum == X86Local::MRMDestReg) ||
(MemFormNum == X86Local::MRMSrcMem &&
RegFormNum == X86Local::MRMSrcReg) ||
(MemFormNum == X86Local::MRMSrcMem4VOp3 &&
RegFormNum == X86Local::MRMSrcReg4VOp3) ||
(MemFormNum == X86Local::MRMSrcMemOp4 &&
RegFormNum == X86Local::MRMSrcRegOp4))
return true;
return false;
}
};
} // end anonymous namespace
void X86FoldTablesEmitter::addEntryWithFlags(FoldTable &Table,
const CodeGenInstruction *RegInstr,
const CodeGenInstruction *MemInstr,
const UnfoldStrategy S,
const unsigned int FoldedInd) {
X86FoldTableEntry Result = X86FoldTableEntry(RegInstr, MemInstr);
Record *RegRec = RegInstr->TheDef;
Record *MemRec = MemInstr->TheDef;
// Only table0 entries should explicitly specify a load or store flag.
if (&Table == &Table0) {
unsigned MemInOpsNum = MemRec->getValueAsDag("InOperandList")->getNumArgs();
unsigned RegInOpsNum = RegRec->getValueAsDag("InOperandList")->getNumArgs();
// If the instruction writes to the folded operand, it will appear as an
// output in the register form instruction and as an input in the memory
// form instruction.
// If the instruction reads from the folded operand, it well appear as in
// input in both forms.
if (MemInOpsNum == RegInOpsNum)
Result.IsLoad = true;
else
Result.IsStore = true;
}
Record *RegOpRec = RegInstr->Operands[FoldedInd].Rec;
Record *MemOpRec = MemInstr->Operands[FoldedInd].Rec;
// Unfolding code generates a load/store instruction according to the size of
// the register in the register form instruction.
// If the register's size is greater than the memory's operand size, do not
// allow unfolding.
if (S == UNFOLD)
Result.CannotUnfold = false;
else if (S == NO_UNFOLD)
Result.CannotUnfold = true;
else if (getRegOperandSize(RegOpRec) > getMemOperandSize(MemOpRec))
Result.CannotUnfold = true; // S == NO_STRATEGY
uint64_t Enc = getValueFromBitsInit(RegRec->getValueAsBitsInit("OpEncBits"));
if (isExplicitAlign(RegInstr)) {
// The instruction require explicitly aligned memory.
BitsInit *VectSize = RegRec->getValueAsBitsInit("VectSize");
uint64_t Value = getValueFromBitsInit(VectSize);
Result.IsAligned = true;
Result.Alignment = Value;
} else if (Enc != X86Local::XOP && Enc != X86Local::VEX &&
Enc != X86Local::EVEX) {
// Instructions with VEX encoding do not require alignment.
if (!isExplicitUnalign(RegInstr) && getMemOperandSize(MemOpRec) > 64) {
// SSE packed vector instructions require a 16 byte alignment.
Result.IsAligned = true;
Result.Alignment = 16;
}
}
Table.push_back(Result);
}
void X86FoldTablesEmitter::updateTables(const CodeGenInstruction *RegInstr,
const CodeGenInstruction *MemInstr,
const UnfoldStrategy S) {
Record *RegRec = RegInstr->TheDef;
Record *MemRec = MemInstr->TheDef;
unsigned MemOutSize = MemRec->getValueAsDag("OutOperandList")->getNumArgs();
unsigned RegOutSize = RegRec->getValueAsDag("OutOperandList")->getNumArgs();
unsigned MemInSize = MemRec->getValueAsDag("InOperandList")->getNumArgs();
unsigned RegInSize = RegRec->getValueAsDag("InOperandList")->getNumArgs();
// Instructions which have the WriteRMW value (Read-Modify-Write) should be
// added to Table2Addr.
if (hasDefInList(MemRec, "SchedRW", "WriteRMW") && MemOutSize != RegOutSize &&
MemInSize == RegInSize) {
addEntryWithFlags(Table2Addr, RegInstr, MemInstr, S, 0);
return;
}
if (MemInSize == RegInSize && MemOutSize == RegOutSize) {
// Load-Folding cases.
// If the i'th register form operand is a register and the i'th memory form
// operand is a memory operand, add instructions to Table#i.
for (unsigned i = RegOutSize, e = RegInstr->Operands.size(); i < e; i++) {
Record *RegOpRec = RegInstr->Operands[i].Rec;
Record *MemOpRec = MemInstr->Operands[i].Rec;
if (isRegisterOperand(RegOpRec) && isMemoryOperand(MemOpRec)) {
switch (i) {
case 0:
addEntryWithFlags(Table0, RegInstr, MemInstr, S, 0);
return;
case 1:
addEntryWithFlags(Table1, RegInstr, MemInstr, S, 1);
return;
case 2:
addEntryWithFlags(Table2, RegInstr, MemInstr, S, 2);
return;
case 3:
addEntryWithFlags(Table3, RegInstr, MemInstr, S, 3);
return;
case 4:
addEntryWithFlags(Table4, RegInstr, MemInstr, S, 4);
return;
}
}
}
} else if (MemInSize == RegInSize + 1 && MemOutSize + 1 == RegOutSize) {
// Store-Folding cases.
// If the memory form instruction performs performs a store, the *output*
// register of the register form instructions disappear and instead a
// memory *input* operand appears in the memory form instruction.
// For example:
// MOVAPSrr => (outs VR128:$dst), (ins VR128:$src)
// MOVAPSmr => (outs), (ins f128mem:$dst, VR128:$src)
Record *RegOpRec = RegInstr->Operands[RegOutSize - 1].Rec;
Record *MemOpRec = MemInstr->Operands[RegOutSize - 1].Rec;
if (isRegisterOperand(RegOpRec) && isMemoryOperand(MemOpRec))
addEntryWithFlags(Table0, RegInstr, MemInstr, S, 0);
}
return;
}
void X86FoldTablesEmitter::run(raw_ostream &OS) {
emitSourceFileHeader("X86 fold tables", OS);
// Holds all memory instructions
std::vector<const CodeGenInstruction *> MemInsts;
// Holds all register instructions - divided according to opcode.
std::map<uint8_t, std::vector<const CodeGenInstruction *>> RegInsts;
ArrayRef<const CodeGenInstruction *> NumberedInstructions =
Target.getInstructionsByEnumValue();
for (const CodeGenInstruction *Inst : NumberedInstructions) {
if (!Inst->TheDef->getNameInit() || !Inst->TheDef->isSubClassOf("X86Inst"))
continue;
const Record *Rec = Inst->TheDef;
// - Do not proceed if the instruction is marked as notMemoryFoldable.
// - Instructions including RST register class operands are not relevant
// for memory folding (for further details check the explanation in
// lib/Target/X86/X86InstrFPStack.td file).
// - Some instructions (listed in the manual map above) use the register
// class ptr_rc_tailcall, which can be of a size 32 or 64, to ensure
// safe mapping of these instruction we manually map them and exclude
// them from the automation.
if (Rec->getValueAsBit("isMemoryFoldable") == false ||
hasRSTRegClass(Inst) || hasPtrTailcallRegClass(Inst))
continue;
// Add all the memory form instructions to MemInsts, and all the register
// form instructions to RegInsts[Opc], where Opc in the opcode of each
// instructions. this helps reducing the runtime of the backend.
if (hasMemoryFormat(Rec))
MemInsts.push_back(Inst);
else if (hasRegisterFormat(Rec)) {
uint8_t Opc = getValueFromBitsInit(Rec->getValueAsBitsInit("Opcode"));
RegInsts[Opc].push_back(Inst);
}
}
// For each memory form instruction, try to find its register form
// instruction.
for (const CodeGenInstruction *MemInst : MemInsts) {
uint8_t Opc =
getValueFromBitsInit(MemInst->TheDef->getValueAsBitsInit("Opcode"));
if (RegInsts.count(Opc) == 0)
continue;
// Two forms (memory & register) of the same instruction must have the same
// opcode. try matching only with register form instructions with the same
// opcode.
std::vector<const CodeGenInstruction *> &OpcRegInsts =
RegInsts.find(Opc)->second;
auto Match = find_if(OpcRegInsts, IsMatch(MemInst, Records));
if (Match != OpcRegInsts.end()) {
const CodeGenInstruction *RegInst = *Match;
// If the matched instruction has it's "FoldGenRegForm" set, map the
// memory form instruction to the register form instruction pointed by
// this field
if (RegInst->TheDef->isValueUnset("FoldGenRegForm")) {
updateTables(RegInst, MemInst);
} else {
const CodeGenInstruction *AltRegInst =
getAltRegInst(RegInst, Records, Target);
updateTables(AltRegInst, MemInst);
}
OpcRegInsts.erase(Match);
}
}
// Add the manually mapped instructions listed above.
for (const ManualMapEntry &Entry : ManualMapSet) {
Record *RegInstIter = Records.getDef(Entry.RegInstStr);
Record *MemInstIter = Records.getDef(Entry.MemInstStr);
updateTables(&(Target.getInstruction(RegInstIter)),
&(Target.getInstruction(MemInstIter)), Entry.Strategy);
}
// Print all tables to raw_ostream OS.
printTable(Table2Addr, "Table2Addr", OS);
printTable(Table0, "Table0", OS);
printTable(Table1, "Table1", OS);
printTable(Table2, "Table2", OS);
printTable(Table3, "Table3", OS);
printTable(Table4, "Table4", OS);
}
namespace llvm {
void EmitX86FoldTables(RecordKeeper &RK, raw_ostream &OS) {
X86FoldTablesEmitter(RK).run(OS);
}
} // namespace llvm
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