Files
clang-p2996/llvm/utils/TableGen/X86EVEX2VEXTablesEmitter.cpp
Craig Topper bb4089d260 Revert "[AVX-512] EVEX2VEX, don't reject intrinsic instructions when both have a memory operand. We should just continue to check other operands instead."
This reverts r297596.

There were other issues that were making this not work that have been fixed now. Reverting this results in a more accurate table.

llvm-svn: 297602
2017-03-13 05:34:03 +00:00

345 lines
12 KiB
C++

//===- utils/TableGen/X86EVEX2VEXTablesEmitter.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 X86 backend EVEX2VEX
/// compression tables.
///
//===----------------------------------------------------------------------===//
#include "CodeGenDAGPatterns.h"
#include "CodeGenTarget.h"
#include "llvm/TableGen/Error.h"
#include "llvm/TableGen/TableGenBackend.h"
using namespace llvm;
namespace {
class X86EVEX2VEXTablesEmitter {
CodeGenTarget Target;
// Hold all non-masked & non-broadcasted EVEX encoded instructions
std::vector<const CodeGenInstruction *> EVEXInsts;
// Hold all VEX encoded instructions. Divided into groups with same opcodes
// to make the search more efficient
std::map<uint64_t, std::vector<const CodeGenInstruction *>> VEXInsts;
typedef std::pair<const CodeGenInstruction *, const CodeGenInstruction *> Entry;
// Represent both compress tables
std::vector<Entry> EVEX2VEX128;
std::vector<Entry> EVEX2VEX256;
// Represents a manually added entry to the tables
class ManualEntry {
public:
std::string EVEXInstStr;
std::string VEXInstStr;
bool Is128Bit;
ManualEntry(std::string EVEXInstStr, std::string VEXInstStr, bool Is128Bit)
: EVEXInstStr(EVEXInstStr), VEXInstStr(VEXInstStr), Is128Bit(Is128Bit) {
}
};
public:
X86EVEX2VEXTablesEmitter(RecordKeeper &R) : Target(R) {}
// run - Output X86 EVEX2VEX tables.
void run(raw_ostream &OS);
private:
// Prints the given table as a C++ array of type
// X86EvexToVexCompressTableEntry
void printTable(const std::vector<Entry> &Table, raw_ostream &OS);
// List of EVEX instructions that match VEX instructions by the encoding
// but do not perform the same operation.
const std::vector<std::string> ExceptionList = {
"VCVTQQ2PD",
"VCVTQQ2PS",
"VPMAXSQ",
"VPMAXUQ",
"VPMINSQ",
"VPMINUQ",
"VPMULLQ",
"VPSRAQ",
"VDBPSADBW",
"VRNDSCALE",
"VSCALEFPS"
};
bool inExceptionList(const CodeGenInstruction *Inst) {
// Instruction's name starts with one of the entries in the exception list
for (const std::string& InstStr : ExceptionList) {
if (Inst->TheDef->getName().startswith(InstStr))
return true;
}
return false;
}
// Some VEX instructions were duplicated to multiple EVEX versions due the
// introduction of mask variants, and thus some of the EVEX versions have
// different encoding than the VEX instruction. In order to maximize the
// compression we add these entries manually.
const std::vector<ManualEntry> ManuallyAddedEntries = {
// EVEX-Inst VEX-Inst Is128-bit
{"VMOVDQU8Z128mr", "VMOVDQUmr", true},
{"VMOVDQU8Z128rm", "VMOVDQUrm", true},
{"VMOVDQU8Z128rr", "VMOVDQUrr", true},
{"VMOVDQU8Z128rr_REV", "VMOVDQUrr_REV", true},
{"VMOVDQU16Z128mr", "VMOVDQUmr", true},
{"VMOVDQU16Z128rm", "VMOVDQUrm", true},
{"VMOVDQU16Z128rr", "VMOVDQUrr", true},
{"VMOVDQU16Z128rr_REV", "VMOVDQUrr_REV", true},
{"VMOVDQU8Z256mr", "VMOVDQUYmr", false},
{"VMOVDQU8Z256rm", "VMOVDQUYrm", false},
{"VMOVDQU8Z256rr", "VMOVDQUYrr", false},
{"VMOVDQU8Z256rr_REV", "VMOVDQUYrr_REV", false},
{"VMOVDQU16Z256mr", "VMOVDQUYmr", false},
{"VMOVDQU16Z256rm", "VMOVDQUYrm", false},
{"VMOVDQU16Z256rr", "VMOVDQUYrr", false},
{"VMOVDQU16Z256rr_REV", "VMOVDQUYrr_REV", false},
{"VPERMILPDZ128mi", "VPERMILPDmi", true},
{"VPERMILPDZ128ri", "VPERMILPDri", true},
{"VPERMILPDZ128rm", "VPERMILPDrm", true},
{"VPERMILPDZ128rr", "VPERMILPDrr", true},
{"VPERMILPDZ256mi", "VPERMILPDYmi", false},
{"VPERMILPDZ256ri", "VPERMILPDYri", false},
{"VPERMILPDZ256rm", "VPERMILPDYrm", false},
{"VPERMILPDZ256rr", "VPERMILPDYrr", false},
{"VPBROADCASTQZ128m", "VPBROADCASTQrm", true},
{"VPBROADCASTQZ128r", "VPBROADCASTQrr", true},
{"VPBROADCASTQZ256m", "VPBROADCASTQYrm", false},
{"VPBROADCASTQZ256r", "VPBROADCASTQYrr", false},
{"VBROADCASTSDZ256m", "VBROADCASTSDYrm", false},
{"VBROADCASTSDZ256r", "VBROADCASTSDYrr", false},
{"VEXTRACTF64x2Z256mr", "VEXTRACTF128mr", false},
{"VEXTRACTF64x2Z256rr", "VEXTRACTF128rr", false},
{"VEXTRACTI64x2Z256mr", "VEXTRACTI128mr", false},
{"VEXTRACTI64x2Z256rr", "VEXTRACTI128rr", false},
{"VINSERTF64x2Z256rm", "VINSERTF128rm", false},
{"VINSERTF64x2Z256rr", "VINSERTF128rr", false},
{"VINSERTI64x2Z256rm", "VINSERTI128rm", false},
{"VINSERTI64x2Z256rr", "VINSERTI128rr", false}
};
};
void X86EVEX2VEXTablesEmitter::printTable(const std::vector<Entry> &Table,
raw_ostream &OS) {
std::string Size = (Table == EVEX2VEX128) ? "128" : "256";
OS << "// X86 EVEX encoded instructions that have a VEX " << Size
<< " encoding\n"
<< "// (table format: <EVEX opcode, VEX-" << Size << " opcode>).\n"
<< "static const X86EvexToVexCompressTableEntry X86EvexToVex" << Size
<< "CompressTable[] = {\n"
<< " // EVEX scalar with corresponding VEX.\n";
// Print all entries added to the table
for (auto Pair : Table) {
OS << " { X86::" << Pair.first->TheDef->getName()
<< ", X86::" << Pair.second->TheDef->getName() << " },\n";
}
// Print the manually added entries
for (const ManualEntry &Entry : ManuallyAddedEntries) {
if ((Table == EVEX2VEX128 && Entry.Is128Bit) ||
(Table == EVEX2VEX256 && !Entry.Is128Bit)) {
OS << " { X86::" << Entry.EVEXInstStr << ", X86::" << Entry.VEXInstStr
<< " },\n";
}
}
OS << "};\n\n";
}
// Return true if the 2 BitsInits are equal
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) {
if (BitInit *Bit1 = dyn_cast<BitInit>(B1->getBit(i))) {
if (BitInit *Bit2 = dyn_cast<BitInit>(B2->getBit(i))) {
if (Bit1->getValue() != Bit2->getValue())
return false;
} else
PrintFatalError("Invalid BitsInit bit");
} else
PrintFatalError("Invalid BitsInit bit");
}
return true;
}
// Calculates the integer value residing BitsInit object
static inline uint64_t getValueFromBitsInit(const BitsInit *B) {
uint64_t Value = 0;
for (unsigned i = 0, e = B->getNumBits(); i != e; ++i) {
if (BitInit *Bit = dyn_cast<BitInit>(B->getBit(i)))
Value |= uint64_t(Bit->getValue()) << i;
else
PrintFatalError("Invalid VectSize bit");
}
return Value;
}
// Function object - Operator() returns true if the given VEX instruction
// matches the EVEX instruction of this object.
class IsMatch {
const CodeGenInstruction *Inst;
public:
IsMatch(const CodeGenInstruction *Inst) : Inst(Inst) {}
bool operator()(const CodeGenInstruction *Inst2) {
Record *Rec1 = Inst->TheDef;
Record *Rec2 = Inst2->TheDef;
uint64_t Rec1WVEX =
getValueFromBitsInit(Rec1->getValueAsBitsInit("VEX_WPrefix"));
uint64_t Rec2WVEX =
getValueFromBitsInit(Rec2->getValueAsBitsInit("VEX_WPrefix"));
if (Rec2->getValueAsDef("OpEnc")->getName().str() != "EncVEX" ||
// VEX/EVEX fields
Rec2->getValueAsDef("OpPrefix") != Rec1->getValueAsDef("OpPrefix") ||
Rec2->getValueAsDef("OpMap") != Rec1->getValueAsDef("OpMap") ||
Rec2->getValueAsBit("hasVEX_4V") != Rec1->getValueAsBit("hasVEX_4V") ||
!equalBitsInits(Rec2->getValueAsBitsInit("EVEX_LL"),
Rec1->getValueAsBitsInit("EVEX_LL")) ||
(Rec1WVEX != 2 && Rec2WVEX != 2 && Rec1WVEX != Rec2WVEX) ||
// Instruction's format
Rec2->getValueAsDef("Form") != Rec1->getValueAsDef("Form") ||
Rec2->getValueAsBit("isAsmParserOnly") !=
Rec1->getValueAsBit("isAsmParserOnly"))
return false;
// 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).
for (unsigned i = 0; i < Inst->Operands.size(); i++) {
Record *OpRec1 = Inst->Operands[i].Rec;
Record *OpRec2 = Inst2->Operands[i].Rec;
if (OpRec1 == OpRec2)
continue;
if (isRegisterOperand(OpRec1) && isRegisterOperand(OpRec2)) {
if (getRegOperandSize(OpRec1) != getRegOperandSize(OpRec2))
return false;
} else if (isMemoryOperand(OpRec1) && isMemoryOperand(OpRec2)) {
return false;
} else if (isImmediateOperand(OpRec1) && isImmediateOperand(OpRec2)) {
if (OpRec1->getValueAsDef("Type") != OpRec2->getValueAsDef("Type"))
return false;
} else
return false;
}
return true;
}
private:
static inline bool isRegisterOperand(const Record *Rec) {
return Rec->isSubClassOf("RegisterClass") ||
Rec->isSubClassOf("RegisterOperand");
}
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";
}
static inline unsigned int getRegOperandSize(const Record *RegRec) {
if (RegRec->isSubClassOf("RegisterClass"))
return RegRec->getValueAsInt("Alignment");
if (RegRec->isSubClassOf("RegisterOperand"))
return RegRec->getValueAsDef("RegClass")->getValueAsInt("Alignment");
llvm_unreachable("Register operand's size not known!");
}
};
void X86EVEX2VEXTablesEmitter::run(raw_ostream &OS) {
emitSourceFileHeader("X86 EVEX2VEX tables", OS);
ArrayRef<const CodeGenInstruction *> NumberedInstructions =
Target.getInstructionsByEnumValue();
for (const CodeGenInstruction *Inst : NumberedInstructions) {
// Filter non-X86 instructions.
if (!Inst->TheDef->isSubClassOf("X86Inst"))
continue;
// Add VEX encoded instructions to one of VEXInsts vectors according to
// it's opcode.
if (Inst->TheDef->getValueAsDef("OpEnc")->getName() == "EncVEX") {
uint64_t Opcode = getValueFromBitsInit(Inst->TheDef->
getValueAsBitsInit("Opcode"));
VEXInsts[Opcode].push_back(Inst);
}
// Add relevant EVEX encoded instructions to EVEXInsts
else if (Inst->TheDef->getValueAsDef("OpEnc")->getName() == "EncEVEX" &&
!Inst->TheDef->getValueAsBit("hasEVEX_K") &&
!Inst->TheDef->getValueAsBit("hasEVEX_B") &&
getValueFromBitsInit(Inst->TheDef->
getValueAsBitsInit("EVEX_LL")) != 2 &&
!inExceptionList(Inst))
EVEXInsts.push_back(Inst);
}
for (const CodeGenInstruction *EVEXInst : EVEXInsts) {
uint64_t Opcode = getValueFromBitsInit(EVEXInst->TheDef->
getValueAsBitsInit("Opcode"));
// For each EVEX instruction look for a VEX match in the appropriate vector
// (instructions with the same opcode) using function object IsMatch.
auto Match = llvm::find_if(VEXInsts[Opcode], IsMatch(EVEXInst));
if (Match != VEXInsts[Opcode].end()) {
const CodeGenInstruction *VEXInst = *Match;
// In case a match is found add new entry to the appropriate table
switch (getValueFromBitsInit(
EVEXInst->TheDef->getValueAsBitsInit("EVEX_LL"))) {
case 0:
EVEX2VEX128.push_back(std::make_pair(EVEXInst, VEXInst)); // {0,0}
break;
case 1:
EVEX2VEX256.push_back(std::make_pair(EVEXInst, VEXInst)); // {0,1}
break;
default:
llvm_unreachable("Instruction's size not fit for the mapping!");
}
}
}
// Print both tables
printTable(EVEX2VEX128, OS);
printTable(EVEX2VEX256, OS);
}
}
namespace llvm {
void EmitX86EVEX2VEXTables(RecordKeeper &RK, raw_ostream &OS) {
X86EVEX2VEXTablesEmitter(RK).run(OS);
}
}