forked from OSchip/llvm-project
1887 lines
65 KiB
C++
1887 lines
65 KiB
C++
//===- HexagonPacketizer.cpp - VLIW packetizer ----------------------------===//
|
|
//
|
|
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
|
|
// See https://llvm.org/LICENSE.txt for license information.
|
|
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
//
|
|
// This implements a simple VLIW packetizer using DFA. The packetizer works on
|
|
// machine basic blocks. For each instruction I in BB, the packetizer consults
|
|
// the DFA to see if machine resources are available to execute I. If so, the
|
|
// packetizer checks if I depends on any instruction J in the current packet.
|
|
// If no dependency is found, I is added to current packet and machine resource
|
|
// is marked as taken. If any dependency is found, a target API call is made to
|
|
// prune the dependence.
|
|
//
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
#include "HexagonVLIWPacketizer.h"
|
|
#include "Hexagon.h"
|
|
#include "HexagonInstrInfo.h"
|
|
#include "HexagonRegisterInfo.h"
|
|
#include "HexagonSubtarget.h"
|
|
#include "llvm/ADT/BitVector.h"
|
|
#include "llvm/ADT/DenseSet.h"
|
|
#include "llvm/ADT/STLExtras.h"
|
|
#include "llvm/ADT/StringExtras.h"
|
|
#include "llvm/Analysis/AliasAnalysis.h"
|
|
#include "llvm/CodeGen/MachineBasicBlock.h"
|
|
#include "llvm/CodeGen/MachineBranchProbabilityInfo.h"
|
|
#include "llvm/CodeGen/MachineDominators.h"
|
|
#include "llvm/CodeGen/MachineFrameInfo.h"
|
|
#include "llvm/CodeGen/MachineFunction.h"
|
|
#include "llvm/CodeGen/MachineFunctionPass.h"
|
|
#include "llvm/CodeGen/MachineInstr.h"
|
|
#include "llvm/CodeGen/MachineInstrBundle.h"
|
|
#include "llvm/CodeGen/MachineLoopInfo.h"
|
|
#include "llvm/CodeGen/MachineOperand.h"
|
|
#include "llvm/CodeGen/ScheduleDAG.h"
|
|
#include "llvm/CodeGen/TargetRegisterInfo.h"
|
|
#include "llvm/CodeGen/TargetSubtargetInfo.h"
|
|
#include "llvm/IR/DebugLoc.h"
|
|
#include "llvm/InitializePasses.h"
|
|
#include "llvm/MC/MCInstrDesc.h"
|
|
#include "llvm/Pass.h"
|
|
#include "llvm/Support/CommandLine.h"
|
|
#include "llvm/Support/Debug.h"
|
|
#include "llvm/Support/ErrorHandling.h"
|
|
#include "llvm/Support/raw_ostream.h"
|
|
#include <cassert>
|
|
#include <cstdint>
|
|
#include <iterator>
|
|
|
|
using namespace llvm;
|
|
|
|
#define DEBUG_TYPE "packets"
|
|
|
|
static cl::opt<bool> DisablePacketizer("disable-packetizer", cl::Hidden,
|
|
cl::ZeroOrMore, cl::init(false),
|
|
cl::desc("Disable Hexagon packetizer pass"));
|
|
|
|
static cl::opt<bool> Slot1Store("slot1-store-slot0-load", cl::Hidden,
|
|
cl::ZeroOrMore, cl::init(true),
|
|
cl::desc("Allow slot1 store and slot0 load"));
|
|
|
|
static cl::opt<bool> PacketizeVolatiles("hexagon-packetize-volatiles",
|
|
cl::ZeroOrMore, cl::Hidden, cl::init(true),
|
|
cl::desc("Allow non-solo packetization of volatile memory references"));
|
|
|
|
static cl::opt<bool> EnableGenAllInsnClass("enable-gen-insn", cl::init(false),
|
|
cl::Hidden, cl::ZeroOrMore, cl::desc("Generate all instruction with TC"));
|
|
|
|
static cl::opt<bool> DisableVecDblNVStores("disable-vecdbl-nv-stores",
|
|
cl::init(false), cl::Hidden, cl::ZeroOrMore,
|
|
cl::desc("Disable vector double new-value-stores"));
|
|
|
|
extern cl::opt<bool> ScheduleInlineAsm;
|
|
|
|
namespace llvm {
|
|
|
|
FunctionPass *createHexagonPacketizer(bool Minimal);
|
|
void initializeHexagonPacketizerPass(PassRegistry&);
|
|
|
|
} // end namespace llvm
|
|
|
|
namespace {
|
|
|
|
class HexagonPacketizer : public MachineFunctionPass {
|
|
public:
|
|
static char ID;
|
|
|
|
HexagonPacketizer(bool Min = false)
|
|
: MachineFunctionPass(ID), Minimal(Min) {}
|
|
|
|
void getAnalysisUsage(AnalysisUsage &AU) const override {
|
|
AU.setPreservesCFG();
|
|
AU.addRequired<AAResultsWrapperPass>();
|
|
AU.addRequired<MachineBranchProbabilityInfo>();
|
|
AU.addRequired<MachineDominatorTree>();
|
|
AU.addRequired<MachineLoopInfo>();
|
|
AU.addPreserved<MachineDominatorTree>();
|
|
AU.addPreserved<MachineLoopInfo>();
|
|
MachineFunctionPass::getAnalysisUsage(AU);
|
|
}
|
|
|
|
StringRef getPassName() const override { return "Hexagon Packetizer"; }
|
|
bool runOnMachineFunction(MachineFunction &Fn) override;
|
|
|
|
MachineFunctionProperties getRequiredProperties() const override {
|
|
return MachineFunctionProperties().set(
|
|
MachineFunctionProperties::Property::NoVRegs);
|
|
}
|
|
|
|
private:
|
|
const HexagonInstrInfo *HII = nullptr;
|
|
const HexagonRegisterInfo *HRI = nullptr;
|
|
const bool Minimal = false;
|
|
};
|
|
|
|
} // end anonymous namespace
|
|
|
|
char HexagonPacketizer::ID = 0;
|
|
|
|
INITIALIZE_PASS_BEGIN(HexagonPacketizer, "hexagon-packetizer",
|
|
"Hexagon Packetizer", false, false)
|
|
INITIALIZE_PASS_DEPENDENCY(MachineDominatorTree)
|
|
INITIALIZE_PASS_DEPENDENCY(MachineBranchProbabilityInfo)
|
|
INITIALIZE_PASS_DEPENDENCY(MachineLoopInfo)
|
|
INITIALIZE_PASS_DEPENDENCY(AAResultsWrapperPass)
|
|
INITIALIZE_PASS_END(HexagonPacketizer, "hexagon-packetizer",
|
|
"Hexagon Packetizer", false, false)
|
|
|
|
HexagonPacketizerList::HexagonPacketizerList(MachineFunction &MF,
|
|
MachineLoopInfo &MLI, AAResults *AA,
|
|
const MachineBranchProbabilityInfo *MBPI, bool Minimal)
|
|
: VLIWPacketizerList(MF, MLI, AA), MBPI(MBPI), MLI(&MLI),
|
|
Minimal(Minimal) {
|
|
HII = MF.getSubtarget<HexagonSubtarget>().getInstrInfo();
|
|
HRI = MF.getSubtarget<HexagonSubtarget>().getRegisterInfo();
|
|
|
|
addMutation(std::make_unique<HexagonSubtarget::UsrOverflowMutation>());
|
|
addMutation(std::make_unique<HexagonSubtarget::HVXMemLatencyMutation>());
|
|
addMutation(std::make_unique<HexagonSubtarget::BankConflictMutation>());
|
|
}
|
|
|
|
// Check if FirstI modifies a register that SecondI reads.
|
|
static bool hasWriteToReadDep(const MachineInstr &FirstI,
|
|
const MachineInstr &SecondI,
|
|
const TargetRegisterInfo *TRI) {
|
|
for (auto &MO : FirstI.operands()) {
|
|
if (!MO.isReg() || !MO.isDef())
|
|
continue;
|
|
Register R = MO.getReg();
|
|
if (SecondI.readsRegister(R, TRI))
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
|
|
static MachineBasicBlock::iterator moveInstrOut(MachineInstr &MI,
|
|
MachineBasicBlock::iterator BundleIt, bool Before) {
|
|
MachineBasicBlock::instr_iterator InsertPt;
|
|
if (Before)
|
|
InsertPt = BundleIt.getInstrIterator();
|
|
else
|
|
InsertPt = std::next(BundleIt).getInstrIterator();
|
|
|
|
MachineBasicBlock &B = *MI.getParent();
|
|
// The instruction should at least be bundled with the preceding instruction
|
|
// (there will always be one, i.e. BUNDLE, if nothing else).
|
|
assert(MI.isBundledWithPred());
|
|
if (MI.isBundledWithSucc()) {
|
|
MI.clearFlag(MachineInstr::BundledSucc);
|
|
MI.clearFlag(MachineInstr::BundledPred);
|
|
} else {
|
|
// If it's not bundled with the successor (i.e. it is the last one
|
|
// in the bundle), then we can simply unbundle it from the predecessor,
|
|
// which will take care of updating the predecessor's flag.
|
|
MI.unbundleFromPred();
|
|
}
|
|
B.splice(InsertPt, &B, MI.getIterator());
|
|
|
|
// Get the size of the bundle without asserting.
|
|
MachineBasicBlock::const_instr_iterator I = BundleIt.getInstrIterator();
|
|
MachineBasicBlock::const_instr_iterator E = B.instr_end();
|
|
unsigned Size = 0;
|
|
for (++I; I != E && I->isBundledWithPred(); ++I)
|
|
++Size;
|
|
|
|
// If there are still two or more instructions, then there is nothing
|
|
// else to be done.
|
|
if (Size > 1)
|
|
return BundleIt;
|
|
|
|
// Otherwise, extract the single instruction out and delete the bundle.
|
|
MachineBasicBlock::iterator NextIt = std::next(BundleIt);
|
|
MachineInstr &SingleI = *BundleIt->getNextNode();
|
|
SingleI.unbundleFromPred();
|
|
assert(!SingleI.isBundledWithSucc());
|
|
BundleIt->eraseFromParent();
|
|
return NextIt;
|
|
}
|
|
|
|
bool HexagonPacketizer::runOnMachineFunction(MachineFunction &MF) {
|
|
auto &HST = MF.getSubtarget<HexagonSubtarget>();
|
|
HII = HST.getInstrInfo();
|
|
HRI = HST.getRegisterInfo();
|
|
auto &MLI = getAnalysis<MachineLoopInfo>();
|
|
auto *AA = &getAnalysis<AAResultsWrapperPass>().getAAResults();
|
|
auto *MBPI = &getAnalysis<MachineBranchProbabilityInfo>();
|
|
|
|
if (EnableGenAllInsnClass)
|
|
HII->genAllInsnTimingClasses(MF);
|
|
|
|
// Instantiate the packetizer.
|
|
bool MinOnly = Minimal || DisablePacketizer || !HST.usePackets() ||
|
|
skipFunction(MF.getFunction());
|
|
HexagonPacketizerList Packetizer(MF, MLI, AA, MBPI, MinOnly);
|
|
|
|
// DFA state table should not be empty.
|
|
assert(Packetizer.getResourceTracker() && "Empty DFA table!");
|
|
|
|
// Loop over all basic blocks and remove KILL pseudo-instructions
|
|
// These instructions confuse the dependence analysis. Consider:
|
|
// D0 = ... (Insn 0)
|
|
// R0 = KILL R0, D0 (Insn 1)
|
|
// R0 = ... (Insn 2)
|
|
// Here, Insn 1 will result in the dependence graph not emitting an output
|
|
// dependence between Insn 0 and Insn 2. This can lead to incorrect
|
|
// packetization
|
|
for (MachineBasicBlock &MB : MF) {
|
|
auto End = MB.end();
|
|
auto MI = MB.begin();
|
|
while (MI != End) {
|
|
auto NextI = std::next(MI);
|
|
if (MI->isKill()) {
|
|
MB.erase(MI);
|
|
End = MB.end();
|
|
}
|
|
MI = NextI;
|
|
}
|
|
}
|
|
|
|
// Loop over all of the basic blocks.
|
|
for (auto &MB : MF) {
|
|
auto Begin = MB.begin(), End = MB.end();
|
|
while (Begin != End) {
|
|
// Find the first non-boundary starting from the end of the last
|
|
// scheduling region.
|
|
MachineBasicBlock::iterator RB = Begin;
|
|
while (RB != End && HII->isSchedulingBoundary(*RB, &MB, MF))
|
|
++RB;
|
|
// Find the first boundary starting from the beginning of the new
|
|
// region.
|
|
MachineBasicBlock::iterator RE = RB;
|
|
while (RE != End && !HII->isSchedulingBoundary(*RE, &MB, MF))
|
|
++RE;
|
|
// Add the scheduling boundary if it's not block end.
|
|
if (RE != End)
|
|
++RE;
|
|
// If RB == End, then RE == End.
|
|
if (RB != End)
|
|
Packetizer.PacketizeMIs(&MB, RB, RE);
|
|
|
|
Begin = RE;
|
|
}
|
|
}
|
|
|
|
Packetizer.unpacketizeSoloInstrs(MF);
|
|
return true;
|
|
}
|
|
|
|
// Reserve resources for a constant extender. Trigger an assertion if the
|
|
// reservation fails.
|
|
void HexagonPacketizerList::reserveResourcesForConstExt() {
|
|
if (!tryAllocateResourcesForConstExt(true))
|
|
llvm_unreachable("Resources not available");
|
|
}
|
|
|
|
bool HexagonPacketizerList::canReserveResourcesForConstExt() {
|
|
return tryAllocateResourcesForConstExt(false);
|
|
}
|
|
|
|
// Allocate resources (i.e. 4 bytes) for constant extender. If succeeded,
|
|
// return true, otherwise, return false.
|
|
bool HexagonPacketizerList::tryAllocateResourcesForConstExt(bool Reserve) {
|
|
auto *ExtMI = MF.CreateMachineInstr(HII->get(Hexagon::A4_ext), DebugLoc());
|
|
bool Avail = ResourceTracker->canReserveResources(*ExtMI);
|
|
if (Reserve && Avail)
|
|
ResourceTracker->reserveResources(*ExtMI);
|
|
MF.DeleteMachineInstr(ExtMI);
|
|
return Avail;
|
|
}
|
|
|
|
bool HexagonPacketizerList::isCallDependent(const MachineInstr &MI,
|
|
SDep::Kind DepType, unsigned DepReg) {
|
|
// Check for LR dependence.
|
|
if (DepReg == HRI->getRARegister())
|
|
return true;
|
|
|
|
if (HII->isDeallocRet(MI))
|
|
if (DepReg == HRI->getFrameRegister() || DepReg == HRI->getStackRegister())
|
|
return true;
|
|
|
|
// Call-like instructions can be packetized with preceding instructions
|
|
// that define registers implicitly used or modified by the call. Explicit
|
|
// uses are still prohibited, as in the case of indirect calls:
|
|
// r0 = ...
|
|
// J2_jumpr r0
|
|
if (DepType == SDep::Data) {
|
|
for (const MachineOperand &MO : MI.operands())
|
|
if (MO.isReg() && MO.getReg() == DepReg && !MO.isImplicit())
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
static bool isRegDependence(const SDep::Kind DepType) {
|
|
return DepType == SDep::Data || DepType == SDep::Anti ||
|
|
DepType == SDep::Output;
|
|
}
|
|
|
|
static bool isDirectJump(const MachineInstr &MI) {
|
|
return MI.getOpcode() == Hexagon::J2_jump;
|
|
}
|
|
|
|
static bool isSchedBarrier(const MachineInstr &MI) {
|
|
switch (MI.getOpcode()) {
|
|
case Hexagon::Y2_barrier:
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
static bool isControlFlow(const MachineInstr &MI) {
|
|
return MI.getDesc().isTerminator() || MI.getDesc().isCall();
|
|
}
|
|
|
|
/// Returns true if the instruction modifies a callee-saved register.
|
|
static bool doesModifyCalleeSavedReg(const MachineInstr &MI,
|
|
const TargetRegisterInfo *TRI) {
|
|
const MachineFunction &MF = *MI.getParent()->getParent();
|
|
for (auto *CSR = TRI->getCalleeSavedRegs(&MF); CSR && *CSR; ++CSR)
|
|
if (MI.modifiesRegister(*CSR, TRI))
|
|
return true;
|
|
return false;
|
|
}
|
|
|
|
// Returns true if an instruction can be promoted to .new predicate or
|
|
// new-value store.
|
|
bool HexagonPacketizerList::isNewifiable(const MachineInstr &MI,
|
|
const TargetRegisterClass *NewRC) {
|
|
// Vector stores can be predicated, and can be new-value stores, but
|
|
// they cannot be predicated on a .new predicate value.
|
|
if (NewRC == &Hexagon::PredRegsRegClass) {
|
|
if (HII->isHVXVec(MI) && MI.mayStore())
|
|
return false;
|
|
return HII->isPredicated(MI) && HII->getDotNewPredOp(MI, nullptr) > 0;
|
|
}
|
|
// If the class is not PredRegs, it could only apply to new-value stores.
|
|
return HII->mayBeNewStore(MI);
|
|
}
|
|
|
|
// Promote an instructiont to its .cur form.
|
|
// At this time, we have already made a call to canPromoteToDotCur and made
|
|
// sure that it can *indeed* be promoted.
|
|
bool HexagonPacketizerList::promoteToDotCur(MachineInstr &MI,
|
|
SDep::Kind DepType, MachineBasicBlock::iterator &MII,
|
|
const TargetRegisterClass* RC) {
|
|
assert(DepType == SDep::Data);
|
|
int CurOpcode = HII->getDotCurOp(MI);
|
|
MI.setDesc(HII->get(CurOpcode));
|
|
return true;
|
|
}
|
|
|
|
void HexagonPacketizerList::cleanUpDotCur() {
|
|
MachineInstr *MI = nullptr;
|
|
for (auto BI : CurrentPacketMIs) {
|
|
LLVM_DEBUG(dbgs() << "Cleanup packet has "; BI->dump(););
|
|
if (HII->isDotCurInst(*BI)) {
|
|
MI = BI;
|
|
continue;
|
|
}
|
|
if (MI) {
|
|
for (auto &MO : BI->operands())
|
|
if (MO.isReg() && MO.getReg() == MI->getOperand(0).getReg())
|
|
return;
|
|
}
|
|
}
|
|
if (!MI)
|
|
return;
|
|
// We did not find a use of the CUR, so de-cur it.
|
|
MI->setDesc(HII->get(HII->getNonDotCurOp(*MI)));
|
|
LLVM_DEBUG(dbgs() << "Demoted CUR "; MI->dump(););
|
|
}
|
|
|
|
// Check to see if an instruction can be dot cur.
|
|
bool HexagonPacketizerList::canPromoteToDotCur(const MachineInstr &MI,
|
|
const SUnit *PacketSU, unsigned DepReg, MachineBasicBlock::iterator &MII,
|
|
const TargetRegisterClass *RC) {
|
|
if (!HII->isHVXVec(MI))
|
|
return false;
|
|
if (!HII->isHVXVec(*MII))
|
|
return false;
|
|
|
|
// Already a dot new instruction.
|
|
if (HII->isDotCurInst(MI) && !HII->mayBeCurLoad(MI))
|
|
return false;
|
|
|
|
if (!HII->mayBeCurLoad(MI))
|
|
return false;
|
|
|
|
// The "cur value" cannot come from inline asm.
|
|
if (PacketSU->getInstr()->isInlineAsm())
|
|
return false;
|
|
|
|
// Make sure candidate instruction uses cur.
|
|
LLVM_DEBUG(dbgs() << "Can we DOT Cur Vector MI\n"; MI.dump();
|
|
dbgs() << "in packet\n";);
|
|
MachineInstr &MJ = *MII;
|
|
LLVM_DEBUG({
|
|
dbgs() << "Checking CUR against ";
|
|
MJ.dump();
|
|
});
|
|
Register DestReg = MI.getOperand(0).getReg();
|
|
bool FoundMatch = false;
|
|
for (auto &MO : MJ.operands())
|
|
if (MO.isReg() && MO.getReg() == DestReg)
|
|
FoundMatch = true;
|
|
if (!FoundMatch)
|
|
return false;
|
|
|
|
// Check for existing uses of a vector register within the packet which
|
|
// would be affected by converting a vector load into .cur formt.
|
|
for (auto BI : CurrentPacketMIs) {
|
|
LLVM_DEBUG(dbgs() << "packet has "; BI->dump(););
|
|
if (BI->readsRegister(DepReg, MF.getSubtarget().getRegisterInfo()))
|
|
return false;
|
|
}
|
|
|
|
LLVM_DEBUG(dbgs() << "Can Dot CUR MI\n"; MI.dump(););
|
|
// We can convert the opcode into a .cur.
|
|
return true;
|
|
}
|
|
|
|
// Promote an instruction to its .new form. At this time, we have already
|
|
// made a call to canPromoteToDotNew and made sure that it can *indeed* be
|
|
// promoted.
|
|
bool HexagonPacketizerList::promoteToDotNew(MachineInstr &MI,
|
|
SDep::Kind DepType, MachineBasicBlock::iterator &MII,
|
|
const TargetRegisterClass* RC) {
|
|
assert(DepType == SDep::Data);
|
|
int NewOpcode;
|
|
if (RC == &Hexagon::PredRegsRegClass)
|
|
NewOpcode = HII->getDotNewPredOp(MI, MBPI);
|
|
else
|
|
NewOpcode = HII->getDotNewOp(MI);
|
|
MI.setDesc(HII->get(NewOpcode));
|
|
return true;
|
|
}
|
|
|
|
bool HexagonPacketizerList::demoteToDotOld(MachineInstr &MI) {
|
|
int NewOpcode = HII->getDotOldOp(MI);
|
|
MI.setDesc(HII->get(NewOpcode));
|
|
return true;
|
|
}
|
|
|
|
bool HexagonPacketizerList::useCallersSP(MachineInstr &MI) {
|
|
unsigned Opc = MI.getOpcode();
|
|
switch (Opc) {
|
|
case Hexagon::S2_storerd_io:
|
|
case Hexagon::S2_storeri_io:
|
|
case Hexagon::S2_storerh_io:
|
|
case Hexagon::S2_storerb_io:
|
|
break;
|
|
default:
|
|
llvm_unreachable("Unexpected instruction");
|
|
}
|
|
unsigned FrameSize = MF.getFrameInfo().getStackSize();
|
|
MachineOperand &Off = MI.getOperand(1);
|
|
int64_t NewOff = Off.getImm() - (FrameSize + HEXAGON_LRFP_SIZE);
|
|
if (HII->isValidOffset(Opc, NewOff, HRI)) {
|
|
Off.setImm(NewOff);
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
void HexagonPacketizerList::useCalleesSP(MachineInstr &MI) {
|
|
unsigned Opc = MI.getOpcode();
|
|
switch (Opc) {
|
|
case Hexagon::S2_storerd_io:
|
|
case Hexagon::S2_storeri_io:
|
|
case Hexagon::S2_storerh_io:
|
|
case Hexagon::S2_storerb_io:
|
|
break;
|
|
default:
|
|
llvm_unreachable("Unexpected instruction");
|
|
}
|
|
unsigned FrameSize = MF.getFrameInfo().getStackSize();
|
|
MachineOperand &Off = MI.getOperand(1);
|
|
Off.setImm(Off.getImm() + FrameSize + HEXAGON_LRFP_SIZE);
|
|
}
|
|
|
|
/// Return true if we can update the offset in MI so that MI and MJ
|
|
/// can be packetized together.
|
|
bool HexagonPacketizerList::updateOffset(SUnit *SUI, SUnit *SUJ) {
|
|
assert(SUI->getInstr() && SUJ->getInstr());
|
|
MachineInstr &MI = *SUI->getInstr();
|
|
MachineInstr &MJ = *SUJ->getInstr();
|
|
|
|
unsigned BPI, OPI;
|
|
if (!HII->getBaseAndOffsetPosition(MI, BPI, OPI))
|
|
return false;
|
|
unsigned BPJ, OPJ;
|
|
if (!HII->getBaseAndOffsetPosition(MJ, BPJ, OPJ))
|
|
return false;
|
|
Register Reg = MI.getOperand(BPI).getReg();
|
|
if (Reg != MJ.getOperand(BPJ).getReg())
|
|
return false;
|
|
// Make sure that the dependences do not restrict adding MI to the packet.
|
|
// That is, ignore anti dependences, and make sure the only data dependence
|
|
// involves the specific register.
|
|
for (const auto &PI : SUI->Preds)
|
|
if (PI.getKind() != SDep::Anti &&
|
|
(PI.getKind() != SDep::Data || PI.getReg() != Reg))
|
|
return false;
|
|
int Incr;
|
|
if (!HII->getIncrementValue(MJ, Incr))
|
|
return false;
|
|
|
|
int64_t Offset = MI.getOperand(OPI).getImm();
|
|
if (!HII->isValidOffset(MI.getOpcode(), Offset+Incr, HRI))
|
|
return false;
|
|
|
|
MI.getOperand(OPI).setImm(Offset + Incr);
|
|
ChangedOffset = Offset;
|
|
return true;
|
|
}
|
|
|
|
/// Undo the changed offset. This is needed if the instruction cannot be
|
|
/// added to the current packet due to a different instruction.
|
|
void HexagonPacketizerList::undoChangedOffset(MachineInstr &MI) {
|
|
unsigned BP, OP;
|
|
if (!HII->getBaseAndOffsetPosition(MI, BP, OP))
|
|
llvm_unreachable("Unable to find base and offset operands.");
|
|
MI.getOperand(OP).setImm(ChangedOffset);
|
|
}
|
|
|
|
enum PredicateKind {
|
|
PK_False,
|
|
PK_True,
|
|
PK_Unknown
|
|
};
|
|
|
|
/// Returns true if an instruction is predicated on p0 and false if it's
|
|
/// predicated on !p0.
|
|
static PredicateKind getPredicateSense(const MachineInstr &MI,
|
|
const HexagonInstrInfo *HII) {
|
|
if (!HII->isPredicated(MI))
|
|
return PK_Unknown;
|
|
if (HII->isPredicatedTrue(MI))
|
|
return PK_True;
|
|
return PK_False;
|
|
}
|
|
|
|
static const MachineOperand &getPostIncrementOperand(const MachineInstr &MI,
|
|
const HexagonInstrInfo *HII) {
|
|
assert(HII->isPostIncrement(MI) && "Not a post increment operation.");
|
|
#ifndef NDEBUG
|
|
// Post Increment means duplicates. Use dense map to find duplicates in the
|
|
// list. Caution: Densemap initializes with the minimum of 64 buckets,
|
|
// whereas there are at most 5 operands in the post increment.
|
|
DenseSet<unsigned> DefRegsSet;
|
|
for (auto &MO : MI.operands())
|
|
if (MO.isReg() && MO.isDef())
|
|
DefRegsSet.insert(MO.getReg());
|
|
|
|
for (auto &MO : MI.operands())
|
|
if (MO.isReg() && MO.isUse() && DefRegsSet.count(MO.getReg()))
|
|
return MO;
|
|
#else
|
|
if (MI.mayLoad()) {
|
|
const MachineOperand &Op1 = MI.getOperand(1);
|
|
// The 2nd operand is always the post increment operand in load.
|
|
assert(Op1.isReg() && "Post increment operand has be to a register.");
|
|
return Op1;
|
|
}
|
|
if (MI.getDesc().mayStore()) {
|
|
const MachineOperand &Op0 = MI.getOperand(0);
|
|
// The 1st operand is always the post increment operand in store.
|
|
assert(Op0.isReg() && "Post increment operand has be to a register.");
|
|
return Op0;
|
|
}
|
|
#endif
|
|
// we should never come here.
|
|
llvm_unreachable("mayLoad or mayStore not set for Post Increment operation");
|
|
}
|
|
|
|
// Get the value being stored.
|
|
static const MachineOperand& getStoreValueOperand(const MachineInstr &MI) {
|
|
// value being stored is always the last operand.
|
|
return MI.getOperand(MI.getNumOperands()-1);
|
|
}
|
|
|
|
static bool isLoadAbsSet(const MachineInstr &MI) {
|
|
unsigned Opc = MI.getOpcode();
|
|
switch (Opc) {
|
|
case Hexagon::L4_loadrd_ap:
|
|
case Hexagon::L4_loadrb_ap:
|
|
case Hexagon::L4_loadrh_ap:
|
|
case Hexagon::L4_loadrub_ap:
|
|
case Hexagon::L4_loadruh_ap:
|
|
case Hexagon::L4_loadri_ap:
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
static const MachineOperand &getAbsSetOperand(const MachineInstr &MI) {
|
|
assert(isLoadAbsSet(MI));
|
|
return MI.getOperand(1);
|
|
}
|
|
|
|
// Can be new value store?
|
|
// Following restrictions are to be respected in convert a store into
|
|
// a new value store.
|
|
// 1. If an instruction uses auto-increment, its address register cannot
|
|
// be a new-value register. Arch Spec 5.4.2.1
|
|
// 2. If an instruction uses absolute-set addressing mode, its address
|
|
// register cannot be a new-value register. Arch Spec 5.4.2.1.
|
|
// 3. If an instruction produces a 64-bit result, its registers cannot be used
|
|
// as new-value registers. Arch Spec 5.4.2.2.
|
|
// 4. If the instruction that sets the new-value register is conditional, then
|
|
// the instruction that uses the new-value register must also be conditional,
|
|
// and both must always have their predicates evaluate identically.
|
|
// Arch Spec 5.4.2.3.
|
|
// 5. There is an implied restriction that a packet cannot have another store,
|
|
// if there is a new value store in the packet. Corollary: if there is
|
|
// already a store in a packet, there can not be a new value store.
|
|
// Arch Spec: 3.4.4.2
|
|
bool HexagonPacketizerList::canPromoteToNewValueStore(const MachineInstr &MI,
|
|
const MachineInstr &PacketMI, unsigned DepReg) {
|
|
// Make sure we are looking at the store, that can be promoted.
|
|
if (!HII->mayBeNewStore(MI))
|
|
return false;
|
|
|
|
// Make sure there is dependency and can be new value'd.
|
|
const MachineOperand &Val = getStoreValueOperand(MI);
|
|
if (Val.isReg() && Val.getReg() != DepReg)
|
|
return false;
|
|
|
|
const MCInstrDesc& MCID = PacketMI.getDesc();
|
|
|
|
// First operand is always the result.
|
|
const TargetRegisterClass *PacketRC = HII->getRegClass(MCID, 0, HRI, MF);
|
|
// Double regs can not feed into new value store: PRM section: 5.4.2.2.
|
|
if (PacketRC == &Hexagon::DoubleRegsRegClass)
|
|
return false;
|
|
|
|
// New-value stores are of class NV (slot 0), dual stores require class ST
|
|
// in slot 0 (PRM 5.5).
|
|
for (auto I : CurrentPacketMIs) {
|
|
SUnit *PacketSU = MIToSUnit.find(I)->second;
|
|
if (PacketSU->getInstr()->mayStore())
|
|
return false;
|
|
}
|
|
|
|
// Make sure it's NOT the post increment register that we are going to
|
|
// new value.
|
|
if (HII->isPostIncrement(MI) &&
|
|
getPostIncrementOperand(MI, HII).getReg() == DepReg) {
|
|
return false;
|
|
}
|
|
|
|
if (HII->isPostIncrement(PacketMI) && PacketMI.mayLoad() &&
|
|
getPostIncrementOperand(PacketMI, HII).getReg() == DepReg) {
|
|
// If source is post_inc, or absolute-set addressing, it can not feed
|
|
// into new value store
|
|
// r3 = memw(r2++#4)
|
|
// memw(r30 + #-1404) = r2.new -> can not be new value store
|
|
// arch spec section: 5.4.2.1.
|
|
return false;
|
|
}
|
|
|
|
if (isLoadAbsSet(PacketMI) && getAbsSetOperand(PacketMI).getReg() == DepReg)
|
|
return false;
|
|
|
|
// If the source that feeds the store is predicated, new value store must
|
|
// also be predicated.
|
|
if (HII->isPredicated(PacketMI)) {
|
|
if (!HII->isPredicated(MI))
|
|
return false;
|
|
|
|
// Check to make sure that they both will have their predicates
|
|
// evaluate identically.
|
|
unsigned predRegNumSrc = 0;
|
|
unsigned predRegNumDst = 0;
|
|
const TargetRegisterClass* predRegClass = nullptr;
|
|
|
|
// Get predicate register used in the source instruction.
|
|
for (auto &MO : PacketMI.operands()) {
|
|
if (!MO.isReg())
|
|
continue;
|
|
predRegNumSrc = MO.getReg();
|
|
predRegClass = HRI->getMinimalPhysRegClass(predRegNumSrc);
|
|
if (predRegClass == &Hexagon::PredRegsRegClass)
|
|
break;
|
|
}
|
|
assert((predRegClass == &Hexagon::PredRegsRegClass) &&
|
|
"predicate register not found in a predicated PacketMI instruction");
|
|
|
|
// Get predicate register used in new-value store instruction.
|
|
for (auto &MO : MI.operands()) {
|
|
if (!MO.isReg())
|
|
continue;
|
|
predRegNumDst = MO.getReg();
|
|
predRegClass = HRI->getMinimalPhysRegClass(predRegNumDst);
|
|
if (predRegClass == &Hexagon::PredRegsRegClass)
|
|
break;
|
|
}
|
|
assert((predRegClass == &Hexagon::PredRegsRegClass) &&
|
|
"predicate register not found in a predicated MI instruction");
|
|
|
|
// New-value register producer and user (store) need to satisfy these
|
|
// constraints:
|
|
// 1) Both instructions should be predicated on the same register.
|
|
// 2) If producer of the new-value register is .new predicated then store
|
|
// should also be .new predicated and if producer is not .new predicated
|
|
// then store should not be .new predicated.
|
|
// 3) Both new-value register producer and user should have same predicate
|
|
// sense, i.e, either both should be negated or both should be non-negated.
|
|
if (predRegNumDst != predRegNumSrc ||
|
|
HII->isDotNewInst(PacketMI) != HII->isDotNewInst(MI) ||
|
|
getPredicateSense(MI, HII) != getPredicateSense(PacketMI, HII))
|
|
return false;
|
|
}
|
|
|
|
// Make sure that other than the new-value register no other store instruction
|
|
// register has been modified in the same packet. Predicate registers can be
|
|
// modified by they should not be modified between the producer and the store
|
|
// instruction as it will make them both conditional on different values.
|
|
// We already know this to be true for all the instructions before and
|
|
// including PacketMI. Howerver, we need to perform the check for the
|
|
// remaining instructions in the packet.
|
|
|
|
unsigned StartCheck = 0;
|
|
|
|
for (auto I : CurrentPacketMIs) {
|
|
SUnit *TempSU = MIToSUnit.find(I)->second;
|
|
MachineInstr &TempMI = *TempSU->getInstr();
|
|
|
|
// Following condition is true for all the instructions until PacketMI is
|
|
// reached (StartCheck is set to 0 before the for loop).
|
|
// StartCheck flag is 1 for all the instructions after PacketMI.
|
|
if (&TempMI != &PacketMI && !StartCheck) // Start processing only after
|
|
continue; // encountering PacketMI.
|
|
|
|
StartCheck = 1;
|
|
if (&TempMI == &PacketMI) // We don't want to check PacketMI for dependence.
|
|
continue;
|
|
|
|
for (auto &MO : MI.operands())
|
|
if (MO.isReg() && TempSU->getInstr()->modifiesRegister(MO.getReg(), HRI))
|
|
return false;
|
|
}
|
|
|
|
// Make sure that for non-POST_INC stores:
|
|
// 1. The only use of reg is DepReg and no other registers.
|
|
// This handles base+index registers.
|
|
// The following store can not be dot new.
|
|
// Eg. r0 = add(r0, #3)
|
|
// memw(r1+r0<<#2) = r0
|
|
if (!HII->isPostIncrement(MI)) {
|
|
for (unsigned opNum = 0; opNum < MI.getNumOperands()-1; opNum++) {
|
|
const MachineOperand &MO = MI.getOperand(opNum);
|
|
if (MO.isReg() && MO.getReg() == DepReg)
|
|
return false;
|
|
}
|
|
}
|
|
|
|
// If data definition is because of implicit definition of the register,
|
|
// do not newify the store. Eg.
|
|
// %r9 = ZXTH %r12, implicit %d6, implicit-def %r12
|
|
// S2_storerh_io %r8, 2, killed %r12; mem:ST2[%scevgep343]
|
|
for (auto &MO : PacketMI.operands()) {
|
|
if (MO.isRegMask() && MO.clobbersPhysReg(DepReg))
|
|
return false;
|
|
if (!MO.isReg() || !MO.isDef() || !MO.isImplicit())
|
|
continue;
|
|
Register R = MO.getReg();
|
|
if (R == DepReg || HRI->isSuperRegister(DepReg, R))
|
|
return false;
|
|
}
|
|
|
|
// Handle imp-use of super reg case. There is a target independent side
|
|
// change that should prevent this situation but I am handling it for
|
|
// just-in-case. For example, we cannot newify R2 in the following case:
|
|
// %r3 = A2_tfrsi 0;
|
|
// S2_storeri_io killed %r0, 0, killed %r2, implicit killed %d1;
|
|
for (auto &MO : MI.operands()) {
|
|
if (MO.isReg() && MO.isUse() && MO.isImplicit() && MO.getReg() == DepReg)
|
|
return false;
|
|
}
|
|
|
|
// Can be dot new store.
|
|
return true;
|
|
}
|
|
|
|
// Can this MI to promoted to either new value store or new value jump.
|
|
bool HexagonPacketizerList::canPromoteToNewValue(const MachineInstr &MI,
|
|
const SUnit *PacketSU, unsigned DepReg,
|
|
MachineBasicBlock::iterator &MII) {
|
|
if (!HII->mayBeNewStore(MI))
|
|
return false;
|
|
|
|
// Check to see the store can be new value'ed.
|
|
MachineInstr &PacketMI = *PacketSU->getInstr();
|
|
if (canPromoteToNewValueStore(MI, PacketMI, DepReg))
|
|
return true;
|
|
|
|
// Check to see the compare/jump can be new value'ed.
|
|
// This is done as a pass on its own. Don't need to check it here.
|
|
return false;
|
|
}
|
|
|
|
static bool isImplicitDependency(const MachineInstr &I, bool CheckDef,
|
|
unsigned DepReg) {
|
|
for (auto &MO : I.operands()) {
|
|
if (CheckDef && MO.isRegMask() && MO.clobbersPhysReg(DepReg))
|
|
return true;
|
|
if (!MO.isReg() || MO.getReg() != DepReg || !MO.isImplicit())
|
|
continue;
|
|
if (CheckDef == MO.isDef())
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
// Check to see if an instruction can be dot new.
|
|
bool HexagonPacketizerList::canPromoteToDotNew(const MachineInstr &MI,
|
|
const SUnit *PacketSU, unsigned DepReg, MachineBasicBlock::iterator &MII,
|
|
const TargetRegisterClass* RC) {
|
|
// Already a dot new instruction.
|
|
if (HII->isDotNewInst(MI) && !HII->mayBeNewStore(MI))
|
|
return false;
|
|
|
|
if (!isNewifiable(MI, RC))
|
|
return false;
|
|
|
|
const MachineInstr &PI = *PacketSU->getInstr();
|
|
|
|
// The "new value" cannot come from inline asm.
|
|
if (PI.isInlineAsm())
|
|
return false;
|
|
|
|
// IMPLICIT_DEFs won't materialize as real instructions, so .new makes no
|
|
// sense.
|
|
if (PI.isImplicitDef())
|
|
return false;
|
|
|
|
// If dependency is trough an implicitly defined register, we should not
|
|
// newify the use.
|
|
if (isImplicitDependency(PI, true, DepReg) ||
|
|
isImplicitDependency(MI, false, DepReg))
|
|
return false;
|
|
|
|
const MCInstrDesc& MCID = PI.getDesc();
|
|
const TargetRegisterClass *VecRC = HII->getRegClass(MCID, 0, HRI, MF);
|
|
if (DisableVecDblNVStores && VecRC == &Hexagon::HvxWRRegClass)
|
|
return false;
|
|
|
|
// predicate .new
|
|
if (RC == &Hexagon::PredRegsRegClass)
|
|
return HII->predCanBeUsedAsDotNew(PI, DepReg);
|
|
|
|
if (RC != &Hexagon::PredRegsRegClass && !HII->mayBeNewStore(MI))
|
|
return false;
|
|
|
|
// Create a dot new machine instruction to see if resources can be
|
|
// allocated. If not, bail out now.
|
|
int NewOpcode = HII->getDotNewOp(MI);
|
|
const MCInstrDesc &D = HII->get(NewOpcode);
|
|
MachineInstr *NewMI = MF.CreateMachineInstr(D, DebugLoc());
|
|
bool ResourcesAvailable = ResourceTracker->canReserveResources(*NewMI);
|
|
MF.DeleteMachineInstr(NewMI);
|
|
if (!ResourcesAvailable)
|
|
return false;
|
|
|
|
// New Value Store only. New Value Jump generated as a separate pass.
|
|
if (!canPromoteToNewValue(MI, PacketSU, DepReg, MII))
|
|
return false;
|
|
|
|
return true;
|
|
}
|
|
|
|
// Go through the packet instructions and search for an anti dependency between
|
|
// them and DepReg from MI. Consider this case:
|
|
// Trying to add
|
|
// a) %r1 = TFRI_cdNotPt %p3, 2
|
|
// to this packet:
|
|
// {
|
|
// b) %p0 = C2_or killed %p3, killed %p0
|
|
// c) %p3 = C2_tfrrp %r23
|
|
// d) %r1 = C2_cmovenewit %p3, 4
|
|
// }
|
|
// The P3 from a) and d) will be complements after
|
|
// a)'s P3 is converted to .new form
|
|
// Anti-dep between c) and b) is irrelevant for this case
|
|
bool HexagonPacketizerList::restrictingDepExistInPacket(MachineInstr &MI,
|
|
unsigned DepReg) {
|
|
SUnit *PacketSUDep = MIToSUnit.find(&MI)->second;
|
|
|
|
for (auto I : CurrentPacketMIs) {
|
|
// We only care for dependencies to predicated instructions
|
|
if (!HII->isPredicated(*I))
|
|
continue;
|
|
|
|
// Scheduling Unit for current insn in the packet
|
|
SUnit *PacketSU = MIToSUnit.find(I)->second;
|
|
|
|
// Look at dependencies between current members of the packet and
|
|
// predicate defining instruction MI. Make sure that dependency is
|
|
// on the exact register we care about.
|
|
if (PacketSU->isSucc(PacketSUDep)) {
|
|
for (unsigned i = 0; i < PacketSU->Succs.size(); ++i) {
|
|
auto &Dep = PacketSU->Succs[i];
|
|
if (Dep.getSUnit() == PacketSUDep && Dep.getKind() == SDep::Anti &&
|
|
Dep.getReg() == DepReg)
|
|
return true;
|
|
}
|
|
}
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
/// Gets the predicate register of a predicated instruction.
|
|
static unsigned getPredicatedRegister(MachineInstr &MI,
|
|
const HexagonInstrInfo *QII) {
|
|
/// We use the following rule: The first predicate register that is a use is
|
|
/// the predicate register of a predicated instruction.
|
|
assert(QII->isPredicated(MI) && "Must be predicated instruction");
|
|
|
|
for (auto &Op : MI.operands()) {
|
|
if (Op.isReg() && Op.getReg() && Op.isUse() &&
|
|
Hexagon::PredRegsRegClass.contains(Op.getReg()))
|
|
return Op.getReg();
|
|
}
|
|
|
|
llvm_unreachable("Unknown instruction operand layout");
|
|
return 0;
|
|
}
|
|
|
|
// Given two predicated instructions, this function detects whether
|
|
// the predicates are complements.
|
|
bool HexagonPacketizerList::arePredicatesComplements(MachineInstr &MI1,
|
|
MachineInstr &MI2) {
|
|
// If we don't know the predicate sense of the instructions bail out early, we
|
|
// need it later.
|
|
if (getPredicateSense(MI1, HII) == PK_Unknown ||
|
|
getPredicateSense(MI2, HII) == PK_Unknown)
|
|
return false;
|
|
|
|
// Scheduling unit for candidate.
|
|
SUnit *SU = MIToSUnit[&MI1];
|
|
|
|
// One corner case deals with the following scenario:
|
|
// Trying to add
|
|
// a) %r24 = A2_tfrt %p0, %r25
|
|
// to this packet:
|
|
// {
|
|
// b) %r25 = A2_tfrf %p0, %r24
|
|
// c) %p0 = C2_cmpeqi %r26, 1
|
|
// }
|
|
//
|
|
// On general check a) and b) are complements, but presence of c) will
|
|
// convert a) to .new form, and then it is not a complement.
|
|
// We attempt to detect it by analyzing existing dependencies in the packet.
|
|
|
|
// Analyze relationships between all existing members of the packet.
|
|
// Look for Anti dependecy on the same predicate reg as used in the
|
|
// candidate.
|
|
for (auto I : CurrentPacketMIs) {
|
|
// Scheduling Unit for current insn in the packet.
|
|
SUnit *PacketSU = MIToSUnit.find(I)->second;
|
|
|
|
// If this instruction in the packet is succeeded by the candidate...
|
|
if (PacketSU->isSucc(SU)) {
|
|
for (unsigned i = 0; i < PacketSU->Succs.size(); ++i) {
|
|
auto Dep = PacketSU->Succs[i];
|
|
// The corner case exist when there is true data dependency between
|
|
// candidate and one of current packet members, this dep is on
|
|
// predicate reg, and there already exist anti dep on the same pred in
|
|
// the packet.
|
|
if (Dep.getSUnit() == SU && Dep.getKind() == SDep::Data &&
|
|
Hexagon::PredRegsRegClass.contains(Dep.getReg())) {
|
|
// Here I know that I is predicate setting instruction with true
|
|
// data dep to candidate on the register we care about - c) in the
|
|
// above example. Now I need to see if there is an anti dependency
|
|
// from c) to any other instruction in the same packet on the pred
|
|
// reg of interest.
|
|
if (restrictingDepExistInPacket(*I, Dep.getReg()))
|
|
return false;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
// If the above case does not apply, check regular complement condition.
|
|
// Check that the predicate register is the same and that the predicate
|
|
// sense is different We also need to differentiate .old vs. .new: !p0
|
|
// is not complementary to p0.new.
|
|
unsigned PReg1 = getPredicatedRegister(MI1, HII);
|
|
unsigned PReg2 = getPredicatedRegister(MI2, HII);
|
|
return PReg1 == PReg2 &&
|
|
Hexagon::PredRegsRegClass.contains(PReg1) &&
|
|
Hexagon::PredRegsRegClass.contains(PReg2) &&
|
|
getPredicateSense(MI1, HII) != getPredicateSense(MI2, HII) &&
|
|
HII->isDotNewInst(MI1) == HII->isDotNewInst(MI2);
|
|
}
|
|
|
|
// Initialize packetizer flags.
|
|
void HexagonPacketizerList::initPacketizerState() {
|
|
Dependence = false;
|
|
PromotedToDotNew = false;
|
|
GlueToNewValueJump = false;
|
|
GlueAllocframeStore = false;
|
|
FoundSequentialDependence = false;
|
|
ChangedOffset = INT64_MAX;
|
|
}
|
|
|
|
// Ignore bundling of pseudo instructions.
|
|
bool HexagonPacketizerList::ignorePseudoInstruction(const MachineInstr &MI,
|
|
const MachineBasicBlock *) {
|
|
if (MI.isDebugInstr())
|
|
return true;
|
|
|
|
if (MI.isCFIInstruction())
|
|
return false;
|
|
|
|
// We must print out inline assembly.
|
|
if (MI.isInlineAsm())
|
|
return false;
|
|
|
|
if (MI.isImplicitDef())
|
|
return false;
|
|
|
|
// We check if MI has any functional units mapped to it. If it doesn't,
|
|
// we ignore the instruction.
|
|
const MCInstrDesc& TID = MI.getDesc();
|
|
auto *IS = ResourceTracker->getInstrItins()->beginStage(TID.getSchedClass());
|
|
unsigned FuncUnits = IS->getUnits();
|
|
return !FuncUnits;
|
|
}
|
|
|
|
bool HexagonPacketizerList::isSoloInstruction(const MachineInstr &MI) {
|
|
// Ensure any bundles created by gather packetize remain seperate.
|
|
if (MI.isBundle())
|
|
return true;
|
|
|
|
if (MI.isEHLabel() || MI.isCFIInstruction())
|
|
return true;
|
|
|
|
// Consider inline asm to not be a solo instruction by default.
|
|
// Inline asm will be put in a packet temporarily, but then it will be
|
|
// removed, and placed outside of the packet (before or after, depending
|
|
// on dependencies). This is to reduce the impact of inline asm as a
|
|
// "packet splitting" instruction.
|
|
if (MI.isInlineAsm() && !ScheduleInlineAsm)
|
|
return true;
|
|
|
|
if (isSchedBarrier(MI))
|
|
return true;
|
|
|
|
if (HII->isSolo(MI))
|
|
return true;
|
|
|
|
if (MI.getOpcode() == Hexagon::A2_nop)
|
|
return true;
|
|
|
|
return false;
|
|
}
|
|
|
|
// Quick check if instructions MI and MJ cannot coexist in the same packet.
|
|
// Limit the tests to be "one-way", e.g. "if MI->isBranch and MJ->isInlineAsm",
|
|
// but not the symmetric case: "if MJ->isBranch and MI->isInlineAsm".
|
|
// For full test call this function twice:
|
|
// cannotCoexistAsymm(MI, MJ) || cannotCoexistAsymm(MJ, MI)
|
|
// Doing the test only one way saves the amount of code in this function,
|
|
// since every test would need to be repeated with the MI and MJ reversed.
|
|
static bool cannotCoexistAsymm(const MachineInstr &MI, const MachineInstr &MJ,
|
|
const HexagonInstrInfo &HII) {
|
|
const MachineFunction *MF = MI.getParent()->getParent();
|
|
if (MF->getSubtarget<HexagonSubtarget>().hasV60OpsOnly() &&
|
|
HII.isHVXMemWithAIndirect(MI, MJ))
|
|
return true;
|
|
|
|
// An inline asm cannot be together with a branch, because we may not be
|
|
// able to remove the asm out after packetizing (i.e. if the asm must be
|
|
// moved past the bundle). Similarly, two asms cannot be together to avoid
|
|
// complications when determining their relative order outside of a bundle.
|
|
if (MI.isInlineAsm())
|
|
return MJ.isInlineAsm() || MJ.isBranch() || MJ.isBarrier() ||
|
|
MJ.isCall() || MJ.isTerminator();
|
|
|
|
// New-value stores cannot coexist with any other stores.
|
|
if (HII.isNewValueStore(MI) && MJ.mayStore())
|
|
return true;
|
|
|
|
switch (MI.getOpcode()) {
|
|
case Hexagon::S2_storew_locked:
|
|
case Hexagon::S4_stored_locked:
|
|
case Hexagon::L2_loadw_locked:
|
|
case Hexagon::L4_loadd_locked:
|
|
case Hexagon::Y2_dccleana:
|
|
case Hexagon::Y2_dccleaninva:
|
|
case Hexagon::Y2_dcinva:
|
|
case Hexagon::Y2_dczeroa:
|
|
case Hexagon::Y4_l2fetch:
|
|
case Hexagon::Y5_l2fetch: {
|
|
// These instructions can only be grouped with ALU32 or non-floating-point
|
|
// XTYPE instructions. Since there is no convenient way of identifying fp
|
|
// XTYPE instructions, only allow grouping with ALU32 for now.
|
|
unsigned TJ = HII.getType(MJ);
|
|
if (TJ != HexagonII::TypeALU32_2op &&
|
|
TJ != HexagonII::TypeALU32_3op &&
|
|
TJ != HexagonII::TypeALU32_ADDI)
|
|
return true;
|
|
break;
|
|
}
|
|
default:
|
|
break;
|
|
}
|
|
|
|
// "False" really means that the quick check failed to determine if
|
|
// I and J cannot coexist.
|
|
return false;
|
|
}
|
|
|
|
// Full, symmetric check.
|
|
bool HexagonPacketizerList::cannotCoexist(const MachineInstr &MI,
|
|
const MachineInstr &MJ) {
|
|
return cannotCoexistAsymm(MI, MJ, *HII) || cannotCoexistAsymm(MJ, MI, *HII);
|
|
}
|
|
|
|
void HexagonPacketizerList::unpacketizeSoloInstrs(MachineFunction &MF) {
|
|
for (auto &B : MF) {
|
|
MachineBasicBlock::iterator BundleIt;
|
|
MachineBasicBlock::instr_iterator NextI;
|
|
for (auto I = B.instr_begin(), E = B.instr_end(); I != E; I = NextI) {
|
|
NextI = std::next(I);
|
|
MachineInstr &MI = *I;
|
|
if (MI.isBundle())
|
|
BundleIt = I;
|
|
if (!MI.isInsideBundle())
|
|
continue;
|
|
|
|
// Decide on where to insert the instruction that we are pulling out.
|
|
// Debug instructions always go before the bundle, but the placement of
|
|
// INLINE_ASM depends on potential dependencies. By default, try to
|
|
// put it before the bundle, but if the asm writes to a register that
|
|
// other instructions in the bundle read, then we need to place it
|
|
// after the bundle (to preserve the bundle semantics).
|
|
bool InsertBeforeBundle;
|
|
if (MI.isInlineAsm())
|
|
InsertBeforeBundle = !hasWriteToReadDep(MI, *BundleIt, HRI);
|
|
else if (MI.isDebugValue())
|
|
InsertBeforeBundle = true;
|
|
else
|
|
continue;
|
|
|
|
BundleIt = moveInstrOut(MI, BundleIt, InsertBeforeBundle);
|
|
}
|
|
}
|
|
}
|
|
|
|
// Check if a given instruction is of class "system".
|
|
static bool isSystemInstr(const MachineInstr &MI) {
|
|
unsigned Opc = MI.getOpcode();
|
|
switch (Opc) {
|
|
case Hexagon::Y2_barrier:
|
|
case Hexagon::Y2_dcfetchbo:
|
|
case Hexagon::Y4_l2fetch:
|
|
case Hexagon::Y5_l2fetch:
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
bool HexagonPacketizerList::hasDeadDependence(const MachineInstr &I,
|
|
const MachineInstr &J) {
|
|
// The dependence graph may not include edges between dead definitions,
|
|
// so without extra checks, we could end up packetizing two instruction
|
|
// defining the same (dead) register.
|
|
if (I.isCall() || J.isCall())
|
|
return false;
|
|
if (HII->isPredicated(I) || HII->isPredicated(J))
|
|
return false;
|
|
|
|
BitVector DeadDefs(Hexagon::NUM_TARGET_REGS);
|
|
for (auto &MO : I.operands()) {
|
|
if (!MO.isReg() || !MO.isDef() || !MO.isDead())
|
|
continue;
|
|
DeadDefs[MO.getReg()] = true;
|
|
}
|
|
|
|
for (auto &MO : J.operands()) {
|
|
if (!MO.isReg() || !MO.isDef() || !MO.isDead())
|
|
continue;
|
|
Register R = MO.getReg();
|
|
if (R != Hexagon::USR_OVF && DeadDefs[R])
|
|
return true;
|
|
}
|
|
return false;
|
|
}
|
|
|
|
bool HexagonPacketizerList::hasControlDependence(const MachineInstr &I,
|
|
const MachineInstr &J) {
|
|
// A save callee-save register function call can only be in a packet
|
|
// with instructions that don't write to the callee-save registers.
|
|
if ((HII->isSaveCalleeSavedRegsCall(I) &&
|
|
doesModifyCalleeSavedReg(J, HRI)) ||
|
|
(HII->isSaveCalleeSavedRegsCall(J) &&
|
|
doesModifyCalleeSavedReg(I, HRI)))
|
|
return true;
|
|
|
|
// Two control flow instructions cannot go in the same packet.
|
|
if (isControlFlow(I) && isControlFlow(J))
|
|
return true;
|
|
|
|
// \ref-manual (7.3.4) A loop setup packet in loopN or spNloop0 cannot
|
|
// contain a speculative indirect jump,
|
|
// a new-value compare jump or a dealloc_return.
|
|
auto isBadForLoopN = [this] (const MachineInstr &MI) -> bool {
|
|
if (MI.isCall() || HII->isDeallocRet(MI) || HII->isNewValueJump(MI))
|
|
return true;
|
|
if (HII->isPredicated(MI) && HII->isPredicatedNew(MI) && HII->isJumpR(MI))
|
|
return true;
|
|
return false;
|
|
};
|
|
|
|
if (HII->isLoopN(I) && isBadForLoopN(J))
|
|
return true;
|
|
if (HII->isLoopN(J) && isBadForLoopN(I))
|
|
return true;
|
|
|
|
// dealloc_return cannot appear in the same packet as a conditional or
|
|
// unconditional jump.
|
|
return HII->isDeallocRet(I) &&
|
|
(J.isBranch() || J.isCall() || J.isBarrier());
|
|
}
|
|
|
|
bool HexagonPacketizerList::hasRegMaskDependence(const MachineInstr &I,
|
|
const MachineInstr &J) {
|
|
// Adding I to a packet that has J.
|
|
|
|
// Regmasks are not reflected in the scheduling dependency graph, so
|
|
// we need to check them manually. This code assumes that regmasks only
|
|
// occur on calls, and the problematic case is when we add an instruction
|
|
// defining a register R to a packet that has a call that clobbers R via
|
|
// a regmask. Those cannot be packetized together, because the call will
|
|
// be executed last. That's also a reson why it is ok to add a call
|
|
// clobbering R to a packet that defines R.
|
|
|
|
// Look for regmasks in J.
|
|
for (const MachineOperand &OpJ : J.operands()) {
|
|
if (!OpJ.isRegMask())
|
|
continue;
|
|
assert((J.isCall() || HII->isTailCall(J)) && "Regmask on a non-call");
|
|
for (const MachineOperand &OpI : I.operands()) {
|
|
if (OpI.isReg()) {
|
|
if (OpJ.clobbersPhysReg(OpI.getReg()))
|
|
return true;
|
|
} else if (OpI.isRegMask()) {
|
|
// Both are regmasks. Assume that they intersect.
|
|
return true;
|
|
}
|
|
}
|
|
}
|
|
return false;
|
|
}
|
|
|
|
bool HexagonPacketizerList::hasDualStoreDependence(const MachineInstr &I,
|
|
const MachineInstr &J) {
|
|
bool SysI = isSystemInstr(I), SysJ = isSystemInstr(J);
|
|
bool StoreI = I.mayStore(), StoreJ = J.mayStore();
|
|
if ((SysI && StoreJ) || (SysJ && StoreI))
|
|
return true;
|
|
|
|
if (StoreI && StoreJ) {
|
|
if (HII->isNewValueInst(J) || HII->isMemOp(J) || HII->isMemOp(I))
|
|
return true;
|
|
} else {
|
|
// A memop cannot be in the same packet with another memop or a store.
|
|
// Two stores can be together, but here I and J cannot both be stores.
|
|
bool MopStI = HII->isMemOp(I) || StoreI;
|
|
bool MopStJ = HII->isMemOp(J) || StoreJ;
|
|
if (MopStI && MopStJ)
|
|
return true;
|
|
}
|
|
|
|
return (StoreJ && HII->isDeallocRet(I)) || (StoreI && HII->isDeallocRet(J));
|
|
}
|
|
|
|
// SUI is the current instruction that is out side of the current packet.
|
|
// SUJ is the current instruction inside the current packet against which that
|
|
// SUI will be packetized.
|
|
bool HexagonPacketizerList::isLegalToPacketizeTogether(SUnit *SUI, SUnit *SUJ) {
|
|
assert(SUI->getInstr() && SUJ->getInstr());
|
|
MachineInstr &I = *SUI->getInstr();
|
|
MachineInstr &J = *SUJ->getInstr();
|
|
|
|
// Clear IgnoreDepMIs when Packet starts.
|
|
if (CurrentPacketMIs.size() == 1)
|
|
IgnoreDepMIs.clear();
|
|
|
|
MachineBasicBlock::iterator II = I.getIterator();
|
|
|
|
// Solo instructions cannot go in the packet.
|
|
assert(!isSoloInstruction(I) && "Unexpected solo instr!");
|
|
|
|
if (cannotCoexist(I, J))
|
|
return false;
|
|
|
|
Dependence = hasDeadDependence(I, J) || hasControlDependence(I, J);
|
|
if (Dependence)
|
|
return false;
|
|
|
|
// Regmasks are not accounted for in the scheduling graph, so we need
|
|
// to explicitly check for dependencies caused by them. They should only
|
|
// appear on calls, so it's not too pessimistic to reject all regmask
|
|
// dependencies.
|
|
Dependence = hasRegMaskDependence(I, J);
|
|
if (Dependence)
|
|
return false;
|
|
|
|
// Dual-store does not allow second store, if the first store is not
|
|
// in SLOT0. New value store, new value jump, dealloc_return and memop
|
|
// always take SLOT0. Arch spec 3.4.4.2.
|
|
Dependence = hasDualStoreDependence(I, J);
|
|
if (Dependence)
|
|
return false;
|
|
|
|
// If an instruction feeds new value jump, glue it.
|
|
MachineBasicBlock::iterator NextMII = I.getIterator();
|
|
++NextMII;
|
|
if (NextMII != I.getParent()->end() && HII->isNewValueJump(*NextMII)) {
|
|
MachineInstr &NextMI = *NextMII;
|
|
|
|
bool secondRegMatch = false;
|
|
const MachineOperand &NOp0 = NextMI.getOperand(0);
|
|
const MachineOperand &NOp1 = NextMI.getOperand(1);
|
|
|
|
if (NOp1.isReg() && I.getOperand(0).getReg() == NOp1.getReg())
|
|
secondRegMatch = true;
|
|
|
|
for (MachineInstr *PI : CurrentPacketMIs) {
|
|
// NVJ can not be part of the dual jump - Arch Spec: section 7.8.
|
|
if (PI->isCall()) {
|
|
Dependence = true;
|
|
break;
|
|
}
|
|
// Validate:
|
|
// 1. Packet does not have a store in it.
|
|
// 2. If the first operand of the nvj is newified, and the second
|
|
// operand is also a reg, it (second reg) is not defined in
|
|
// the same packet.
|
|
// 3. If the second operand of the nvj is newified, (which means
|
|
// first operand is also a reg), first reg is not defined in
|
|
// the same packet.
|
|
if (PI->getOpcode() == Hexagon::S2_allocframe || PI->mayStore() ||
|
|
HII->isLoopN(*PI)) {
|
|
Dependence = true;
|
|
break;
|
|
}
|
|
// Check #2/#3.
|
|
const MachineOperand &OpR = secondRegMatch ? NOp0 : NOp1;
|
|
if (OpR.isReg() && PI->modifiesRegister(OpR.getReg(), HRI)) {
|
|
Dependence = true;
|
|
break;
|
|
}
|
|
}
|
|
|
|
GlueToNewValueJump = true;
|
|
if (Dependence)
|
|
return false;
|
|
}
|
|
|
|
// There no dependency between a prolog instruction and its successor.
|
|
if (!SUJ->isSucc(SUI))
|
|
return true;
|
|
|
|
for (unsigned i = 0; i < SUJ->Succs.size(); ++i) {
|
|
if (FoundSequentialDependence)
|
|
break;
|
|
|
|
if (SUJ->Succs[i].getSUnit() != SUI)
|
|
continue;
|
|
|
|
SDep::Kind DepType = SUJ->Succs[i].getKind();
|
|
// For direct calls:
|
|
// Ignore register dependences for call instructions for packetization
|
|
// purposes except for those due to r31 and predicate registers.
|
|
//
|
|
// For indirect calls:
|
|
// Same as direct calls + check for true dependences to the register
|
|
// used in the indirect call.
|
|
//
|
|
// We completely ignore Order dependences for call instructions.
|
|
//
|
|
// For returns:
|
|
// Ignore register dependences for return instructions like jumpr,
|
|
// dealloc return unless we have dependencies on the explicit uses
|
|
// of the registers used by jumpr (like r31) or dealloc return
|
|
// (like r29 or r30).
|
|
unsigned DepReg = 0;
|
|
const TargetRegisterClass *RC = nullptr;
|
|
if (DepType == SDep::Data) {
|
|
DepReg = SUJ->Succs[i].getReg();
|
|
RC = HRI->getMinimalPhysRegClass(DepReg);
|
|
}
|
|
|
|
if (I.isCall() || HII->isJumpR(I) || I.isReturn() || HII->isTailCall(I)) {
|
|
if (!isRegDependence(DepType))
|
|
continue;
|
|
if (!isCallDependent(I, DepType, SUJ->Succs[i].getReg()))
|
|
continue;
|
|
}
|
|
|
|
if (DepType == SDep::Data) {
|
|
if (canPromoteToDotCur(J, SUJ, DepReg, II, RC))
|
|
if (promoteToDotCur(J, DepType, II, RC))
|
|
continue;
|
|
}
|
|
|
|
// Data dpendence ok if we have load.cur.
|
|
if (DepType == SDep::Data && HII->isDotCurInst(J)) {
|
|
if (HII->isHVXVec(I))
|
|
continue;
|
|
}
|
|
|
|
// For instructions that can be promoted to dot-new, try to promote.
|
|
if (DepType == SDep::Data) {
|
|
if (canPromoteToDotNew(I, SUJ, DepReg, II, RC)) {
|
|
if (promoteToDotNew(I, DepType, II, RC)) {
|
|
PromotedToDotNew = true;
|
|
if (cannotCoexist(I, J))
|
|
FoundSequentialDependence = true;
|
|
continue;
|
|
}
|
|
}
|
|
if (HII->isNewValueJump(I))
|
|
continue;
|
|
}
|
|
|
|
// For predicated instructions, if the predicates are complements then
|
|
// there can be no dependence.
|
|
if (HII->isPredicated(I) && HII->isPredicated(J) &&
|
|
arePredicatesComplements(I, J)) {
|
|
// Not always safe to do this translation.
|
|
// DAG Builder attempts to reduce dependence edges using transitive
|
|
// nature of dependencies. Here is an example:
|
|
//
|
|
// r0 = tfr_pt ... (1)
|
|
// r0 = tfr_pf ... (2)
|
|
// r0 = tfr_pt ... (3)
|
|
//
|
|
// There will be an output dependence between (1)->(2) and (2)->(3).
|
|
// However, there is no dependence edge between (1)->(3). This results
|
|
// in all 3 instructions going in the same packet. We ignore dependce
|
|
// only once to avoid this situation.
|
|
auto Itr = find(IgnoreDepMIs, &J);
|
|
if (Itr != IgnoreDepMIs.end()) {
|
|
Dependence = true;
|
|
return false;
|
|
}
|
|
IgnoreDepMIs.push_back(&I);
|
|
continue;
|
|
}
|
|
|
|
// Ignore Order dependences between unconditional direct branches
|
|
// and non-control-flow instructions.
|
|
if (isDirectJump(I) && !J.isBranch() && !J.isCall() &&
|
|
DepType == SDep::Order)
|
|
continue;
|
|
|
|
// Ignore all dependences for jumps except for true and output
|
|
// dependences.
|
|
if (I.isConditionalBranch() && DepType != SDep::Data &&
|
|
DepType != SDep::Output)
|
|
continue;
|
|
|
|
if (DepType == SDep::Output) {
|
|
FoundSequentialDependence = true;
|
|
break;
|
|
}
|
|
|
|
// For Order dependences:
|
|
// 1. Volatile loads/stores can be packetized together, unless other
|
|
// rules prevent is.
|
|
// 2. Store followed by a load is not allowed.
|
|
// 3. Store followed by a store is valid.
|
|
// 4. Load followed by any memory operation is allowed.
|
|
if (DepType == SDep::Order) {
|
|
if (!PacketizeVolatiles) {
|
|
bool OrdRefs = I.hasOrderedMemoryRef() || J.hasOrderedMemoryRef();
|
|
if (OrdRefs) {
|
|
FoundSequentialDependence = true;
|
|
break;
|
|
}
|
|
}
|
|
// J is first, I is second.
|
|
bool LoadJ = J.mayLoad(), StoreJ = J.mayStore();
|
|
bool LoadI = I.mayLoad(), StoreI = I.mayStore();
|
|
bool NVStoreJ = HII->isNewValueStore(J);
|
|
bool NVStoreI = HII->isNewValueStore(I);
|
|
bool IsVecJ = HII->isHVXVec(J);
|
|
bool IsVecI = HII->isHVXVec(I);
|
|
|
|
if (Slot1Store && MF.getSubtarget<HexagonSubtarget>().hasV65Ops() &&
|
|
((LoadJ && StoreI && !NVStoreI) ||
|
|
(StoreJ && LoadI && !NVStoreJ)) &&
|
|
(J.getOpcode() != Hexagon::S2_allocframe &&
|
|
I.getOpcode() != Hexagon::S2_allocframe) &&
|
|
(J.getOpcode() != Hexagon::L2_deallocframe &&
|
|
I.getOpcode() != Hexagon::L2_deallocframe) &&
|
|
(!HII->isMemOp(J) && !HII->isMemOp(I)) && (!IsVecJ && !IsVecI))
|
|
setmemShufDisabled(true);
|
|
else
|
|
if (StoreJ && LoadI && alias(J, I)) {
|
|
FoundSequentialDependence = true;
|
|
break;
|
|
}
|
|
|
|
if (!StoreJ)
|
|
if (!LoadJ || (!LoadI && !StoreI)) {
|
|
// If J is neither load nor store, assume a dependency.
|
|
// If J is a load, but I is neither, also assume a dependency.
|
|
FoundSequentialDependence = true;
|
|
break;
|
|
}
|
|
// Store followed by store: not OK on V2.
|
|
// Store followed by load: not OK on all.
|
|
// Load followed by store: OK on all.
|
|
// Load followed by load: OK on all.
|
|
continue;
|
|
}
|
|
|
|
// Special case for ALLOCFRAME: even though there is dependency
|
|
// between ALLOCFRAME and subsequent store, allow it to be packetized
|
|
// in a same packet. This implies that the store is using the caller's
|
|
// SP. Hence, offset needs to be updated accordingly.
|
|
if (DepType == SDep::Data && J.getOpcode() == Hexagon::S2_allocframe) {
|
|
unsigned Opc = I.getOpcode();
|
|
switch (Opc) {
|
|
case Hexagon::S2_storerd_io:
|
|
case Hexagon::S2_storeri_io:
|
|
case Hexagon::S2_storerh_io:
|
|
case Hexagon::S2_storerb_io:
|
|
if (I.getOperand(0).getReg() == HRI->getStackRegister()) {
|
|
// Since this store is to be glued with allocframe in the same
|
|
// packet, it will use SP of the previous stack frame, i.e.
|
|
// caller's SP. Therefore, we need to recalculate offset
|
|
// according to this change.
|
|
GlueAllocframeStore = useCallersSP(I);
|
|
if (GlueAllocframeStore)
|
|
continue;
|
|
}
|
|
break;
|
|
default:
|
|
break;
|
|
}
|
|
}
|
|
|
|
// There are certain anti-dependencies that cannot be ignored.
|
|
// Specifically:
|
|
// J2_call ... implicit-def %r0 ; SUJ
|
|
// R0 = ... ; SUI
|
|
// Those cannot be packetized together, since the call will observe
|
|
// the effect of the assignment to R0.
|
|
if ((DepType == SDep::Anti || DepType == SDep::Output) && J.isCall()) {
|
|
// Check if I defines any volatile register. We should also check
|
|
// registers that the call may read, but these happen to be a
|
|
// subset of the volatile register set.
|
|
for (const MachineOperand &Op : I.operands()) {
|
|
if (Op.isReg() && Op.isDef()) {
|
|
Register R = Op.getReg();
|
|
if (!J.readsRegister(R, HRI) && !J.modifiesRegister(R, HRI))
|
|
continue;
|
|
} else if (!Op.isRegMask()) {
|
|
// If I has a regmask assume dependency.
|
|
continue;
|
|
}
|
|
FoundSequentialDependence = true;
|
|
break;
|
|
}
|
|
}
|
|
|
|
// Skip over remaining anti-dependences. Two instructions that are
|
|
// anti-dependent can share a packet, since in most such cases all
|
|
// operands are read before any modifications take place.
|
|
// The exceptions are branch and call instructions, since they are
|
|
// executed after all other instructions have completed (at least
|
|
// conceptually).
|
|
if (DepType != SDep::Anti) {
|
|
FoundSequentialDependence = true;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (FoundSequentialDependence) {
|
|
Dependence = true;
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
bool HexagonPacketizerList::isLegalToPruneDependencies(SUnit *SUI, SUnit *SUJ) {
|
|
assert(SUI->getInstr() && SUJ->getInstr());
|
|
MachineInstr &I = *SUI->getInstr();
|
|
MachineInstr &J = *SUJ->getInstr();
|
|
|
|
bool Coexist = !cannotCoexist(I, J);
|
|
|
|
if (Coexist && !Dependence)
|
|
return true;
|
|
|
|
// Check if the instruction was promoted to a dot-new. If so, demote it
|
|
// back into a dot-old.
|
|
if (PromotedToDotNew)
|
|
demoteToDotOld(I);
|
|
|
|
cleanUpDotCur();
|
|
// Check if the instruction (must be a store) was glued with an allocframe
|
|
// instruction. If so, restore its offset to its original value, i.e. use
|
|
// current SP instead of caller's SP.
|
|
if (GlueAllocframeStore) {
|
|
useCalleesSP(I);
|
|
GlueAllocframeStore = false;
|
|
}
|
|
|
|
if (ChangedOffset != INT64_MAX)
|
|
undoChangedOffset(I);
|
|
|
|
if (GlueToNewValueJump) {
|
|
// Putting I and J together would prevent the new-value jump from being
|
|
// packetized with the producer. In that case I and J must be separated.
|
|
GlueToNewValueJump = false;
|
|
return false;
|
|
}
|
|
|
|
if (!Coexist)
|
|
return false;
|
|
|
|
if (ChangedOffset == INT64_MAX && updateOffset(SUI, SUJ)) {
|
|
FoundSequentialDependence = false;
|
|
Dependence = false;
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
|
|
bool HexagonPacketizerList::foundLSInPacket() {
|
|
bool FoundLoad = false;
|
|
bool FoundStore = false;
|
|
|
|
for (auto MJ : CurrentPacketMIs) {
|
|
unsigned Opc = MJ->getOpcode();
|
|
if (Opc == Hexagon::S2_allocframe || Opc == Hexagon::L2_deallocframe)
|
|
continue;
|
|
if (HII->isMemOp(*MJ))
|
|
continue;
|
|
if (MJ->mayLoad())
|
|
FoundLoad = true;
|
|
if (MJ->mayStore() && !HII->isNewValueStore(*MJ))
|
|
FoundStore = true;
|
|
}
|
|
return FoundLoad && FoundStore;
|
|
}
|
|
|
|
|
|
MachineBasicBlock::iterator
|
|
HexagonPacketizerList::addToPacket(MachineInstr &MI) {
|
|
MachineBasicBlock::iterator MII = MI.getIterator();
|
|
MachineBasicBlock *MBB = MI.getParent();
|
|
|
|
if (CurrentPacketMIs.empty())
|
|
PacketStalls = false;
|
|
PacketStalls |= producesStall(MI);
|
|
|
|
if (MI.isImplicitDef()) {
|
|
// Add to the packet to allow subsequent instructions to be checked
|
|
// properly.
|
|
CurrentPacketMIs.push_back(&MI);
|
|
return MII;
|
|
}
|
|
assert(ResourceTracker->canReserveResources(MI));
|
|
|
|
bool ExtMI = HII->isExtended(MI) || HII->isConstExtended(MI);
|
|
bool Good = true;
|
|
|
|
if (GlueToNewValueJump) {
|
|
MachineInstr &NvjMI = *++MII;
|
|
// We need to put both instructions in the same packet: MI and NvjMI.
|
|
// Either of them can require a constant extender. Try to add both to
|
|
// the current packet, and if that fails, end the packet and start a
|
|
// new one.
|
|
ResourceTracker->reserveResources(MI);
|
|
if (ExtMI)
|
|
Good = tryAllocateResourcesForConstExt(true);
|
|
|
|
bool ExtNvjMI = HII->isExtended(NvjMI) || HII->isConstExtended(NvjMI);
|
|
if (Good) {
|
|
if (ResourceTracker->canReserveResources(NvjMI))
|
|
ResourceTracker->reserveResources(NvjMI);
|
|
else
|
|
Good = false;
|
|
}
|
|
if (Good && ExtNvjMI)
|
|
Good = tryAllocateResourcesForConstExt(true);
|
|
|
|
if (!Good) {
|
|
endPacket(MBB, MI);
|
|
assert(ResourceTracker->canReserveResources(MI));
|
|
ResourceTracker->reserveResources(MI);
|
|
if (ExtMI) {
|
|
assert(canReserveResourcesForConstExt());
|
|
tryAllocateResourcesForConstExt(true);
|
|
}
|
|
assert(ResourceTracker->canReserveResources(NvjMI));
|
|
ResourceTracker->reserveResources(NvjMI);
|
|
if (ExtNvjMI) {
|
|
assert(canReserveResourcesForConstExt());
|
|
reserveResourcesForConstExt();
|
|
}
|
|
}
|
|
CurrentPacketMIs.push_back(&MI);
|
|
CurrentPacketMIs.push_back(&NvjMI);
|
|
return MII;
|
|
}
|
|
|
|
ResourceTracker->reserveResources(MI);
|
|
if (ExtMI && !tryAllocateResourcesForConstExt(true)) {
|
|
endPacket(MBB, MI);
|
|
if (PromotedToDotNew)
|
|
demoteToDotOld(MI);
|
|
if (GlueAllocframeStore) {
|
|
useCalleesSP(MI);
|
|
GlueAllocframeStore = false;
|
|
}
|
|
ResourceTracker->reserveResources(MI);
|
|
reserveResourcesForConstExt();
|
|
}
|
|
|
|
CurrentPacketMIs.push_back(&MI);
|
|
return MII;
|
|
}
|
|
|
|
void HexagonPacketizerList::endPacket(MachineBasicBlock *MBB,
|
|
MachineBasicBlock::iterator EndMI) {
|
|
// Replace VLIWPacketizerList::endPacket(MBB, EndMI).
|
|
LLVM_DEBUG({
|
|
if (!CurrentPacketMIs.empty()) {
|
|
dbgs() << "Finalizing packet:\n";
|
|
unsigned Idx = 0;
|
|
for (MachineInstr *MI : CurrentPacketMIs) {
|
|
unsigned R = ResourceTracker->getUsedResources(Idx++);
|
|
dbgs() << " * [res:0x" << utohexstr(R) << "] " << *MI;
|
|
}
|
|
}
|
|
});
|
|
|
|
bool memShufDisabled = getmemShufDisabled();
|
|
if (memShufDisabled && !foundLSInPacket()) {
|
|
setmemShufDisabled(false);
|
|
LLVM_DEBUG(dbgs() << " Not added to NoShufPacket\n");
|
|
}
|
|
memShufDisabled = getmemShufDisabled();
|
|
|
|
OldPacketMIs.clear();
|
|
for (MachineInstr *MI : CurrentPacketMIs) {
|
|
MachineBasicBlock::instr_iterator NextMI = std::next(MI->getIterator());
|
|
for (auto &I : make_range(HII->expandVGatherPseudo(*MI), NextMI))
|
|
OldPacketMIs.push_back(&I);
|
|
}
|
|
CurrentPacketMIs.clear();
|
|
|
|
if (OldPacketMIs.size() > 1) {
|
|
MachineBasicBlock::instr_iterator FirstMI(OldPacketMIs.front());
|
|
MachineBasicBlock::instr_iterator LastMI(EndMI.getInstrIterator());
|
|
finalizeBundle(*MBB, FirstMI, LastMI);
|
|
auto BundleMII = std::prev(FirstMI);
|
|
if (memShufDisabled)
|
|
HII->setBundleNoShuf(BundleMII);
|
|
|
|
setmemShufDisabled(false);
|
|
}
|
|
|
|
ResourceTracker->clearResources();
|
|
LLVM_DEBUG(dbgs() << "End packet\n");
|
|
}
|
|
|
|
bool HexagonPacketizerList::shouldAddToPacket(const MachineInstr &MI) {
|
|
if (Minimal)
|
|
return false;
|
|
return !producesStall(MI);
|
|
}
|
|
|
|
// V60 forward scheduling.
|
|
bool HexagonPacketizerList::producesStall(const MachineInstr &I) {
|
|
// If the packet already stalls, then ignore the stall from a subsequent
|
|
// instruction in the same packet.
|
|
if (PacketStalls)
|
|
return false;
|
|
|
|
// Check whether the previous packet is in a different loop. If this is the
|
|
// case, there is little point in trying to avoid a stall because that would
|
|
// favor the rare case (loop entry) over the common case (loop iteration).
|
|
//
|
|
// TODO: We should really be able to check all the incoming edges if this is
|
|
// the first packet in a basic block, so we can avoid stalls from the loop
|
|
// backedge.
|
|
if (!OldPacketMIs.empty()) {
|
|
auto *OldBB = OldPacketMIs.front()->getParent();
|
|
auto *ThisBB = I.getParent();
|
|
if (MLI->getLoopFor(OldBB) != MLI->getLoopFor(ThisBB))
|
|
return false;
|
|
}
|
|
|
|
SUnit *SUI = MIToSUnit[const_cast<MachineInstr *>(&I)];
|
|
|
|
// If the latency is 0 and there is a data dependence between this
|
|
// instruction and any instruction in the current packet, we disregard any
|
|
// potential stalls due to the instructions in the previous packet. Most of
|
|
// the instruction pairs that can go together in the same packet have 0
|
|
// latency between them. The exceptions are
|
|
// 1. NewValueJumps as they're generated much later and the latencies can't
|
|
// be changed at that point.
|
|
// 2. .cur instructions, if its consumer has a 0 latency successor (such as
|
|
// .new). In this case, the latency between .cur and the consumer stays
|
|
// non-zero even though we can have both .cur and .new in the same packet.
|
|
// Changing the latency to 0 is not an option as it causes software pipeliner
|
|
// to not pipeline in some cases.
|
|
|
|
// For Example:
|
|
// {
|
|
// I1: v6.cur = vmem(r0++#1)
|
|
// I2: v7 = valign(v6,v4,r2)
|
|
// I3: vmem(r5++#1) = v7.new
|
|
// }
|
|
// Here I2 and I3 has 0 cycle latency, but I1 and I2 has 2.
|
|
|
|
for (auto J : CurrentPacketMIs) {
|
|
SUnit *SUJ = MIToSUnit[J];
|
|
for (auto &Pred : SUI->Preds)
|
|
if (Pred.getSUnit() == SUJ)
|
|
if ((Pred.getLatency() == 0 && Pred.isAssignedRegDep()) ||
|
|
HII->isNewValueJump(I) || HII->isToBeScheduledASAP(*J, I))
|
|
return false;
|
|
}
|
|
|
|
// Check if the latency is greater than one between this instruction and any
|
|
// instruction in the previous packet.
|
|
for (auto J : OldPacketMIs) {
|
|
SUnit *SUJ = MIToSUnit[J];
|
|
for (auto &Pred : SUI->Preds)
|
|
if (Pred.getSUnit() == SUJ && Pred.getLatency() > 1)
|
|
return true;
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Public Constructor Functions
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
FunctionPass *llvm::createHexagonPacketizer(bool Minimal) {
|
|
return new HexagonPacketizer(Minimal);
|
|
}
|