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being used to grab subtarget specific things that we can grab from the MachineFunction anyhow. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@219650 91177308-0d34-0410-b5e6-96231b3b80d8
1425 lines
51 KiB
C++
1425 lines
51 KiB
C++
//===----- HexagonPacketizer.cpp - vliw packetizer ---------------------===//
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//
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// The LLVM Compiler Infrastructure
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// This implements a simple VLIW packetizer using DFA. The packetizer works on
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// machine basic blocks. For each instruction I in BB, the packetizer consults
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// the DFA to see if machine resources are available to execute I. If so, the
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// packetizer checks if I depends on any instruction J in the current packet.
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// If no dependency is found, I is added to current packet and machine resource
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// is marked as taken. If any dependency is found, a target API call is made to
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// prune the dependence.
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//
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//===----------------------------------------------------------------------===//
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#include "llvm/CodeGen/DFAPacketizer.h"
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#include "Hexagon.h"
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#include "HexagonMachineFunctionInfo.h"
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#include "HexagonRegisterInfo.h"
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#include "HexagonSubtarget.h"
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#include "HexagonTargetMachine.h"
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#include "llvm/ADT/DenseMap.h"
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#include "llvm/ADT/Statistic.h"
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#include "llvm/CodeGen/LatencyPriorityQueue.h"
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#include "llvm/CodeGen/MachineDominators.h"
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#include "llvm/CodeGen/MachineFrameInfo.h"
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#include "llvm/CodeGen/MachineFunctionAnalysis.h"
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#include "llvm/CodeGen/MachineFunctionPass.h"
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#include "llvm/CodeGen/MachineInstrBuilder.h"
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#include "llvm/CodeGen/MachineLoopInfo.h"
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#include "llvm/CodeGen/MachineRegisterInfo.h"
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#include "llvm/CodeGen/Passes.h"
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#include "llvm/CodeGen/ScheduleDAG.h"
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#include "llvm/CodeGen/ScheduleDAGInstrs.h"
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#include "llvm/CodeGen/ScheduleHazardRecognizer.h"
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#include "llvm/CodeGen/SchedulerRegistry.h"
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#include "llvm/MC/MCInstrItineraries.h"
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#include "llvm/Support/CommandLine.h"
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#include "llvm/Support/Compiler.h"
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#include "llvm/Support/Debug.h"
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#include "llvm/Support/MathExtras.h"
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#include "llvm/Target/TargetInstrInfo.h"
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#include "llvm/Target/TargetMachine.h"
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#include "llvm/Target/TargetRegisterInfo.h"
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#include <map>
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#include <vector>
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using namespace llvm;
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#define DEBUG_TYPE "packets"
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static cl::opt<bool> PacketizeVolatiles("hexagon-packetize-volatiles",
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cl::ZeroOrMore, cl::Hidden, cl::init(true),
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cl::desc("Allow non-solo packetization of volatile memory references"));
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namespace llvm {
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void initializeHexagonPacketizerPass(PassRegistry&);
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}
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namespace {
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class HexagonPacketizer : public MachineFunctionPass {
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public:
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static char ID;
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HexagonPacketizer() : MachineFunctionPass(ID) {
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initializeHexagonPacketizerPass(*PassRegistry::getPassRegistry());
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}
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void getAnalysisUsage(AnalysisUsage &AU) const override {
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AU.setPreservesCFG();
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AU.addRequired<MachineDominatorTree>();
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AU.addRequired<MachineBranchProbabilityInfo>();
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AU.addPreserved<MachineDominatorTree>();
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AU.addRequired<MachineLoopInfo>();
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AU.addPreserved<MachineLoopInfo>();
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MachineFunctionPass::getAnalysisUsage(AU);
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}
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const char *getPassName() const override {
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return "Hexagon Packetizer";
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}
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bool runOnMachineFunction(MachineFunction &Fn) override;
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};
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char HexagonPacketizer::ID = 0;
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class HexagonPacketizerList : public VLIWPacketizerList {
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private:
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// Has the instruction been promoted to a dot-new instruction.
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bool PromotedToDotNew;
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// Has the instruction been glued to allocframe.
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bool GlueAllocframeStore;
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// Has the feeder instruction been glued to new value jump.
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bool GlueToNewValueJump;
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// Check if there is a dependence between some instruction already in this
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// packet and this instruction.
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bool Dependence;
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// Only check for dependence if there are resources available to
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// schedule this instruction.
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bool FoundSequentialDependence;
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/// \brief A handle to the branch probability pass.
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const MachineBranchProbabilityInfo *MBPI;
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// Track MIs with ignored dependece.
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std::vector<MachineInstr*> IgnoreDepMIs;
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public:
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// Ctor.
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HexagonPacketizerList(MachineFunction &MF, MachineLoopInfo &MLI,
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const MachineBranchProbabilityInfo *MBPI);
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// initPacketizerState - initialize some internal flags.
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void initPacketizerState() override;
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// ignorePseudoInstruction - Ignore bundling of pseudo instructions.
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bool ignorePseudoInstruction(MachineInstr *MI,
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MachineBasicBlock *MBB) override;
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// isSoloInstruction - return true if instruction MI can not be packetized
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// with any other instruction, which means that MI itself is a packet.
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bool isSoloInstruction(MachineInstr *MI) override;
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// isLegalToPacketizeTogether - Is it legal to packetize SUI and SUJ
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// together.
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bool isLegalToPacketizeTogether(SUnit *SUI, SUnit *SUJ) override;
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// isLegalToPruneDependencies - Is it legal to prune dependece between SUI
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// and SUJ.
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bool isLegalToPruneDependencies(SUnit *SUI, SUnit *SUJ) override;
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MachineBasicBlock::iterator addToPacket(MachineInstr *MI) override;
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private:
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bool IsCallDependent(MachineInstr* MI, SDep::Kind DepType, unsigned DepReg);
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bool PromoteToDotNew(MachineInstr* MI, SDep::Kind DepType,
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MachineBasicBlock::iterator &MII,
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const TargetRegisterClass* RC);
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bool CanPromoteToDotNew(MachineInstr *MI, SUnit *PacketSU, unsigned DepReg,
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const std::map<MachineInstr *, SUnit *> &MIToSUnit,
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MachineBasicBlock::iterator &MII,
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const TargetRegisterClass *RC);
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bool
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CanPromoteToNewValue(MachineInstr *MI, SUnit *PacketSU, unsigned DepReg,
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const std::map<MachineInstr *, SUnit *> &MIToSUnit,
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MachineBasicBlock::iterator &MII);
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bool CanPromoteToNewValueStore(
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MachineInstr *MI, MachineInstr *PacketMI, unsigned DepReg,
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const std::map<MachineInstr *, SUnit *> &MIToSUnit);
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bool DemoteToDotOld(MachineInstr *MI);
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bool ArePredicatesComplements(
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MachineInstr *MI1, MachineInstr *MI2,
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const std::map<MachineInstr *, SUnit *> &MIToSUnit);
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bool RestrictingDepExistInPacket(MachineInstr *, unsigned,
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const std::map<MachineInstr *, SUnit *> &);
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bool isNewifiable(MachineInstr* MI);
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bool isCondInst(MachineInstr* MI);
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bool tryAllocateResourcesForConstExt(MachineInstr* MI);
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bool canReserveResourcesForConstExt(MachineInstr *MI);
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void reserveResourcesForConstExt(MachineInstr* MI);
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bool isNewValueInst(MachineInstr* MI);
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};
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}
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INITIALIZE_PASS_BEGIN(HexagonPacketizer, "packets", "Hexagon Packetizer",
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false, false)
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INITIALIZE_PASS_DEPENDENCY(MachineDominatorTree)
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INITIALIZE_PASS_DEPENDENCY(MachineBranchProbabilityInfo)
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INITIALIZE_PASS_DEPENDENCY(MachineLoopInfo)
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INITIALIZE_AG_DEPENDENCY(AliasAnalysis)
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INITIALIZE_PASS_END(HexagonPacketizer, "packets", "Hexagon Packetizer",
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false, false)
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// HexagonPacketizerList Ctor.
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HexagonPacketizerList::HexagonPacketizerList(
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MachineFunction &MF, MachineLoopInfo &MLI,
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const MachineBranchProbabilityInfo *MBPI)
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: VLIWPacketizerList(MF, MLI, true) {
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this->MBPI = MBPI;
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}
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bool HexagonPacketizer::runOnMachineFunction(MachineFunction &Fn) {
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const TargetInstrInfo *TII = Fn.getSubtarget().getInstrInfo();
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MachineLoopInfo &MLI = getAnalysis<MachineLoopInfo>();
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const MachineBranchProbabilityInfo *MBPI =
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&getAnalysis<MachineBranchProbabilityInfo>();
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// Instantiate the packetizer.
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HexagonPacketizerList Packetizer(Fn, MLI, MBPI);
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// DFA state table should not be empty.
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assert(Packetizer.getResourceTracker() && "Empty DFA table!");
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//
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// Loop over all basic blocks and remove KILL pseudo-instructions
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// These instructions confuse the dependence analysis. Consider:
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// D0 = ... (Insn 0)
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// R0 = KILL R0, D0 (Insn 1)
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// R0 = ... (Insn 2)
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// Here, Insn 1 will result in the dependence graph not emitting an output
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// dependence between Insn 0 and Insn 2. This can lead to incorrect
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// packetization
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//
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for (MachineFunction::iterator MBB = Fn.begin(), MBBe = Fn.end();
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MBB != MBBe; ++MBB) {
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MachineBasicBlock::iterator End = MBB->end();
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MachineBasicBlock::iterator MI = MBB->begin();
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while (MI != End) {
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if (MI->isKill()) {
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MachineBasicBlock::iterator DeleteMI = MI;
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++MI;
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MBB->erase(DeleteMI);
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End = MBB->end();
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continue;
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}
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++MI;
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}
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}
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// Loop over all of the basic blocks.
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for (MachineFunction::iterator MBB = Fn.begin(), MBBe = Fn.end();
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MBB != MBBe; ++MBB) {
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// Find scheduling regions and schedule / packetize each region.
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unsigned RemainingCount = MBB->size();
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for(MachineBasicBlock::iterator RegionEnd = MBB->end();
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RegionEnd != MBB->begin();) {
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// The next region starts above the previous region. Look backward in the
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// instruction stream until we find the nearest boundary.
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MachineBasicBlock::iterator I = RegionEnd;
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for(;I != MBB->begin(); --I, --RemainingCount) {
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if (TII->isSchedulingBoundary(std::prev(I), MBB, Fn))
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break;
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}
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I = MBB->begin();
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// Skip empty scheduling regions.
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if (I == RegionEnd) {
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RegionEnd = std::prev(RegionEnd);
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--RemainingCount;
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continue;
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}
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// Skip regions with one instruction.
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if (I == std::prev(RegionEnd)) {
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RegionEnd = std::prev(RegionEnd);
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continue;
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}
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Packetizer.PacketizeMIs(MBB, I, RegionEnd);
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RegionEnd = I;
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}
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}
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return true;
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}
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static bool IsIndirectCall(MachineInstr* MI) {
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return ((MI->getOpcode() == Hexagon::CALLR) ||
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(MI->getOpcode() == Hexagon::CALLRv3));
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}
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// Reserve resources for constant extender. Trigure an assertion if
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// reservation fail.
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void HexagonPacketizerList::reserveResourcesForConstExt(MachineInstr* MI) {
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const HexagonInstrInfo *QII = (const HexagonInstrInfo *) TII;
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MachineFunction *MF = MI->getParent()->getParent();
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MachineInstr *PseudoMI = MF->CreateMachineInstr(QII->get(Hexagon::IMMEXT_i),
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MI->getDebugLoc());
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if (ResourceTracker->canReserveResources(PseudoMI)) {
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ResourceTracker->reserveResources(PseudoMI);
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MI->getParent()->getParent()->DeleteMachineInstr(PseudoMI);
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} else {
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MI->getParent()->getParent()->DeleteMachineInstr(PseudoMI);
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llvm_unreachable("can not reserve resources for constant extender.");
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}
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return;
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}
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bool HexagonPacketizerList::canReserveResourcesForConstExt(MachineInstr *MI) {
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const HexagonInstrInfo *QII = (const HexagonInstrInfo *) TII;
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assert((QII->isExtended(MI) || QII->isConstExtended(MI)) &&
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"Should only be called for constant extended instructions");
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MachineFunction *MF = MI->getParent()->getParent();
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MachineInstr *PseudoMI = MF->CreateMachineInstr(QII->get(Hexagon::IMMEXT_i),
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MI->getDebugLoc());
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bool CanReserve = ResourceTracker->canReserveResources(PseudoMI);
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MF->DeleteMachineInstr(PseudoMI);
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return CanReserve;
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}
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// Allocate resources (i.e. 4 bytes) for constant extender. If succeed, return
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// true, otherwise, return false.
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bool HexagonPacketizerList::tryAllocateResourcesForConstExt(MachineInstr* MI) {
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const HexagonInstrInfo *QII = (const HexagonInstrInfo *) TII;
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MachineFunction *MF = MI->getParent()->getParent();
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MachineInstr *PseudoMI = MF->CreateMachineInstr(QII->get(Hexagon::IMMEXT_i),
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MI->getDebugLoc());
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if (ResourceTracker->canReserveResources(PseudoMI)) {
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ResourceTracker->reserveResources(PseudoMI);
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MI->getParent()->getParent()->DeleteMachineInstr(PseudoMI);
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return true;
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} else {
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MI->getParent()->getParent()->DeleteMachineInstr(PseudoMI);
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return false;
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}
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}
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bool HexagonPacketizerList::IsCallDependent(MachineInstr* MI,
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SDep::Kind DepType,
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unsigned DepReg) {
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const HexagonInstrInfo *QII = (const HexagonInstrInfo *) TII;
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const HexagonRegisterInfo *QRI =
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(const HexagonRegisterInfo *)MF.getSubtarget().getRegisterInfo();
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// Check for lr dependence
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if (DepReg == QRI->getRARegister()) {
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return true;
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}
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if (QII->isDeallocRet(MI)) {
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if (DepReg == QRI->getFrameRegister() ||
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DepReg == QRI->getStackRegister())
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return true;
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}
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// Check if this is a predicate dependence
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const TargetRegisterClass* RC = QRI->getMinimalPhysRegClass(DepReg);
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if (RC == &Hexagon::PredRegsRegClass) {
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return true;
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}
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//
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// Lastly check for an operand used in an indirect call
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// If we had an attribute for checking if an instruction is an indirect call,
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// then we could have avoided this relatively brittle implementation of
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// IsIndirectCall()
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//
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// Assumes that the first operand of the CALLr is the function address
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//
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if (IsIndirectCall(MI) && (DepType == SDep::Data)) {
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MachineOperand MO = MI->getOperand(0);
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if (MO.isReg() && MO.isUse() && (MO.getReg() == DepReg)) {
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return true;
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}
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}
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return false;
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}
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static bool IsRegDependence(const SDep::Kind DepType) {
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return (DepType == SDep::Data || DepType == SDep::Anti ||
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DepType == SDep::Output);
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}
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static bool IsDirectJump(MachineInstr* MI) {
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return (MI->getOpcode() == Hexagon::JMP);
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}
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static bool IsSchedBarrier(MachineInstr* MI) {
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switch (MI->getOpcode()) {
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case Hexagon::BARRIER:
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return true;
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}
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return false;
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}
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static bool IsControlFlow(MachineInstr* MI) {
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return (MI->getDesc().isTerminator() || MI->getDesc().isCall());
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}
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static bool IsLoopN(MachineInstr *MI) {
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return (MI->getOpcode() == Hexagon::LOOP0_i ||
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MI->getOpcode() == Hexagon::LOOP0_r);
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}
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/// DoesModifyCalleeSavedReg - Returns true if the instruction modifies a
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/// callee-saved register.
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static bool DoesModifyCalleeSavedReg(MachineInstr *MI,
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const TargetRegisterInfo *TRI) {
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for (const MCPhysReg *CSR = TRI->getCalleeSavedRegs(); *CSR; ++CSR) {
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unsigned CalleeSavedReg = *CSR;
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if (MI->modifiesRegister(CalleeSavedReg, TRI))
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return true;
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}
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return false;
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}
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// Returns true if an instruction can be promoted to .new predicate
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// or new-value store.
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bool HexagonPacketizerList::isNewifiable(MachineInstr* MI) {
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const HexagonInstrInfo *QII = (const HexagonInstrInfo *) TII;
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if ( isCondInst(MI) || QII->mayBeNewStore(MI))
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return true;
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else
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return false;
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}
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bool HexagonPacketizerList::isCondInst (MachineInstr* MI) {
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const HexagonInstrInfo *QII = (const HexagonInstrInfo *) TII;
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const MCInstrDesc& TID = MI->getDesc();
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// bug 5670: until that is fixed,
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// this portion is disabled.
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if ( TID.isConditionalBranch() // && !IsRegisterJump(MI)) ||
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|| QII->isConditionalTransfer(MI)
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|| QII->isConditionalALU32(MI)
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|| QII->isConditionalLoad(MI)
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|| QII->isConditionalStore(MI)) {
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return true;
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}
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return false;
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}
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// Promote an instructiont to its .new form.
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// At this time, we have already made a call to CanPromoteToDotNew
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// and made sure that it can *indeed* be promoted.
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bool HexagonPacketizerList::PromoteToDotNew(MachineInstr* MI,
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SDep::Kind DepType, MachineBasicBlock::iterator &MII,
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const TargetRegisterClass* RC) {
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assert (DepType == SDep::Data);
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const HexagonInstrInfo *QII = (const HexagonInstrInfo *) TII;
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int NewOpcode;
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if (RC == &Hexagon::PredRegsRegClass)
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NewOpcode = QII->GetDotNewPredOp(MI, MBPI);
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else
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NewOpcode = QII->GetDotNewOp(MI);
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MI->setDesc(QII->get(NewOpcode));
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return true;
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}
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bool HexagonPacketizerList::DemoteToDotOld(MachineInstr* MI) {
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const HexagonInstrInfo *QII = (const HexagonInstrInfo *) TII;
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int NewOpcode = QII->GetDotOldOp(MI->getOpcode());
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MI->setDesc(QII->get(NewOpcode));
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return true;
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}
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enum PredicateKind {
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PK_False,
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PK_True,
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PK_Unknown
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};
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/// Returns true if an instruction is predicated on p0 and false if it's
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/// predicated on !p0.
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static PredicateKind getPredicateSense(MachineInstr* MI,
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const HexagonInstrInfo *QII) {
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if (!QII->isPredicated(MI))
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return PK_Unknown;
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if (QII->isPredicatedTrue(MI))
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return PK_True;
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return PK_False;
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}
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static MachineOperand& GetPostIncrementOperand(MachineInstr *MI,
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const HexagonInstrInfo *QII) {
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assert(QII->isPostIncrement(MI) && "Not a post increment operation.");
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#ifndef NDEBUG
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// Post Increment means duplicates. Use dense map to find duplicates in the
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// list. Caution: Densemap initializes with the minimum of 64 buckets,
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// whereas there are at most 5 operands in the post increment.
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DenseMap<unsigned, unsigned> DefRegsSet;
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for(unsigned opNum = 0; opNum < MI->getNumOperands(); opNum++)
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if (MI->getOperand(opNum).isReg() &&
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MI->getOperand(opNum).isDef()) {
|
|
DefRegsSet[MI->getOperand(opNum).getReg()] = 1;
|
|
}
|
|
|
|
for(unsigned opNum = 0; opNum < MI->getNumOperands(); opNum++)
|
|
if (MI->getOperand(opNum).isReg() &&
|
|
MI->getOperand(opNum).isUse()) {
|
|
if (DefRegsSet[MI->getOperand(opNum).getReg()]) {
|
|
return MI->getOperand(opNum);
|
|
}
|
|
}
|
|
#else
|
|
if (MI->getDesc().mayLoad()) {
|
|
// The 2nd operand is always the post increment operand in load.
|
|
assert(MI->getOperand(1).isReg() &&
|
|
"Post increment operand has be to a register.");
|
|
return (MI->getOperand(1));
|
|
}
|
|
if (MI->getDesc().mayStore()) {
|
|
// The 1st operand is always the post increment operand in store.
|
|
assert(MI->getOperand(0).isReg() &&
|
|
"Post increment operand has be to a register.");
|
|
return (MI->getOperand(0));
|
|
}
|
|
#endif
|
|
// we should never come here.
|
|
llvm_unreachable("mayLoad or mayStore not set for Post Increment operation");
|
|
}
|
|
|
|
// get the value being stored
|
|
static MachineOperand& GetStoreValueOperand(MachineInstr *MI) {
|
|
// value being stored is always the last operand.
|
|
return (MI->getOperand(MI->getNumOperands()-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.TODO: This is not enabled as
|
|
// as absolute-set address mode patters are not implemented.
|
|
// 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 a 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 of a packet can not 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(
|
|
MachineInstr *MI, MachineInstr *PacketMI, unsigned DepReg,
|
|
const std::map<MachineInstr *, SUnit *> &MIToSUnit) {
|
|
const HexagonInstrInfo *QII = (const HexagonInstrInfo *) TII;
|
|
// Make sure we are looking at the store, that can be promoted.
|
|
if (!QII->mayBeNewStore(MI))
|
|
return false;
|
|
|
|
// Make sure there is dependency and can be new value'ed
|
|
if (GetStoreValueOperand(MI).isReg() &&
|
|
GetStoreValueOperand(MI).getReg() != DepReg)
|
|
return false;
|
|
|
|
const HexagonRegisterInfo *QRI =
|
|
(const HexagonRegisterInfo *)MF.getSubtarget().getRegisterInfo();
|
|
const MCInstrDesc& MCID = PacketMI->getDesc();
|
|
// first operand is always the result
|
|
|
|
const TargetRegisterClass* PacketRC = QII->getRegClass(MCID, 0, QRI, MF);
|
|
|
|
// if there is already an store in the packet, no can do new value store
|
|
// Arch Spec 3.4.4.2.
|
|
for (std::vector<MachineInstr*>::iterator VI = CurrentPacketMIs.begin(),
|
|
VE = CurrentPacketMIs.end();
|
|
(VI != VE); ++VI) {
|
|
SUnit *PacketSU = MIToSUnit.find(*VI)->second;
|
|
if (PacketSU->getInstr()->getDesc().mayStore() ||
|
|
// if we have mayStore = 1 set on ALLOCFRAME and DEALLOCFRAME,
|
|
// then we don't need this
|
|
PacketSU->getInstr()->getOpcode() == Hexagon::ALLOCFRAME ||
|
|
PacketSU->getInstr()->getOpcode() == Hexagon::DEALLOCFRAME)
|
|
return false;
|
|
}
|
|
|
|
if (PacketRC == &Hexagon::DoubleRegsRegClass) {
|
|
// new value store constraint: double regs can not feed into new value store
|
|
// arch spec section: 5.4.2.2
|
|
return false;
|
|
}
|
|
|
|
// Make sure it's NOT the post increment register that we are going to
|
|
// new value.
|
|
if (QII->isPostIncrement(MI) &&
|
|
MI->getDesc().mayStore() &&
|
|
GetPostIncrementOperand(MI, QII).getReg() == DepReg) {
|
|
return false;
|
|
}
|
|
|
|
if (QII->isPostIncrement(PacketMI) &&
|
|
PacketMI->getDesc().mayLoad() &&
|
|
GetPostIncrementOperand(PacketMI, QII).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 the source that feeds the store is predicated, new value store must
|
|
// also be predicated.
|
|
if (QII->isPredicated(PacketMI)) {
|
|
if (!QII->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(unsigned opNum = 0; opNum < PacketMI->getNumOperands(); opNum++) {
|
|
if ( PacketMI->getOperand(opNum).isReg())
|
|
predRegNumSrc = PacketMI->getOperand(opNum).getReg();
|
|
predRegClass = QRI->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(unsigned opNum = 0; opNum < MI->getNumOperands(); opNum++) {
|
|
if ( MI->getOperand(opNum).isReg())
|
|
predRegNumDst = MI->getOperand(opNum).getReg();
|
|
predRegClass = QRI->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 none negated.
|
|
|
|
if (( predRegNumDst != predRegNumSrc) ||
|
|
QII->isDotNewInst(PacketMI) != QII->isDotNewInst(MI) ||
|
|
getPredicateSense(MI, QII) != getPredicateSense(PacketMI, QII)) {
|
|
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.
|
|
|
|
std::vector<MachineInstr*>::iterator VI;
|
|
std::vector<MachineInstr*>::iterator VE;
|
|
unsigned StartCheck = 0;
|
|
|
|
for (VI=CurrentPacketMIs.begin(), VE = CurrentPacketMIs.end();
|
|
(VI != VE); ++VI) {
|
|
SUnit *TempSU = MIToSUnit.find(*VI)->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(unsigned opNum = 0; opNum < MI->getNumOperands(); opNum++) {
|
|
if (MI->getOperand(opNum).isReg() &&
|
|
TempSU->getInstr()->modifiesRegister(MI->getOperand(opNum).getReg(),
|
|
QRI))
|
|
return false;
|
|
}
|
|
}
|
|
|
|
// Make sure that for non-POST_INC stores:
|
|
// 1. The only use of reg is DepReg and no other registers.
|
|
// This handles V4 base+index registers.
|
|
// The following store can not be dot new.
|
|
// Eg. r0 = add(r0, #3)a
|
|
// memw(r1+r0<<#2) = r0
|
|
if (!QII->isPostIncrement(MI) &&
|
|
GetStoreValueOperand(MI).isReg() &&
|
|
GetStoreValueOperand(MI).getReg() == DepReg) {
|
|
for(unsigned opNum = 0; opNum < MI->getNumOperands()-1; opNum++) {
|
|
if (MI->getOperand(opNum).isReg() &&
|
|
MI->getOperand(opNum).getReg() == DepReg) {
|
|
return false;
|
|
}
|
|
}
|
|
// 2. If data definition is because of implicit definition of the register,
|
|
// do not newify the store. Eg.
|
|
// %R9<def> = ZXTH %R12, %D6<imp-use>, %R12<imp-def>
|
|
// STrih_indexed %R8, 2, %R12<kill>; mem:ST2[%scevgep343]
|
|
for(unsigned opNum = 0; opNum < PacketMI->getNumOperands(); opNum++) {
|
|
if (PacketMI->getOperand(opNum).isReg() &&
|
|
PacketMI->getOperand(opNum).getReg() == DepReg &&
|
|
PacketMI->getOperand(opNum).isDef() &&
|
|
PacketMI->getOperand(opNum).isImplicit()) {
|
|
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(
|
|
MachineInstr *MI, SUnit *PacketSU, unsigned DepReg,
|
|
const std::map<MachineInstr *, SUnit *> &MIToSUnit,
|
|
MachineBasicBlock::iterator &MII) {
|
|
|
|
const HexagonInstrInfo *QII = (const HexagonInstrInfo *) TII;
|
|
const HexagonRegisterInfo *QRI =
|
|
(const HexagonRegisterInfo *)MF.getSubtarget().getRegisterInfo();
|
|
if (!QRI->Subtarget.hasV4TOps() ||
|
|
!QII->mayBeNewStore(MI))
|
|
return false;
|
|
|
|
MachineInstr *PacketMI = PacketSU->getInstr();
|
|
|
|
// Check to see the store can be new value'ed.
|
|
if (CanPromoteToNewValueStore(MI, PacketMI, DepReg, MIToSUnit))
|
|
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;
|
|
}
|
|
|
|
// Check to see if an instruction can be dot new
|
|
// There are three kinds.
|
|
// 1. dot new on predicate - V2/V3/V4
|
|
// 2. dot new on stores NV/ST - V4
|
|
// 3. dot new on jump NV/J - V4 -- This is generated in a pass.
|
|
bool HexagonPacketizerList::CanPromoteToDotNew(
|
|
MachineInstr *MI, SUnit *PacketSU, unsigned DepReg,
|
|
const std::map<MachineInstr *, SUnit *> &MIToSUnit,
|
|
MachineBasicBlock::iterator &MII, const TargetRegisterClass *RC) {
|
|
const HexagonInstrInfo *QII = (const HexagonInstrInfo *) TII;
|
|
// Already a dot new instruction.
|
|
if (QII->isDotNewInst(MI) && !QII->mayBeNewStore(MI))
|
|
return false;
|
|
|
|
if (!isNewifiable(MI))
|
|
return false;
|
|
|
|
// predicate .new
|
|
if (RC == &Hexagon::PredRegsRegClass && isCondInst(MI))
|
|
return true;
|
|
else if (RC != &Hexagon::PredRegsRegClass &&
|
|
!QII->mayBeNewStore(MI)) // MI is not a new-value store
|
|
return false;
|
|
else {
|
|
// Create a dot new machine instruction to see if resources can be
|
|
// allocated. If not, bail out now.
|
|
int NewOpcode = QII->GetDotNewOp(MI);
|
|
const MCInstrDesc &desc = QII->get(NewOpcode);
|
|
DebugLoc dl;
|
|
MachineInstr *NewMI =
|
|
MI->getParent()->getParent()->CreateMachineInstr(desc, dl);
|
|
bool ResourcesAvailable = ResourceTracker->canReserveResources(NewMI);
|
|
MI->getParent()->getParent()->DeleteMachineInstr(NewMI);
|
|
|
|
if (!ResourcesAvailable)
|
|
return false;
|
|
|
|
// new value store only
|
|
// new new value jump generated as a passes
|
|
if (!CanPromoteToNewValue(MI, PacketSU, DepReg, MIToSUnit, MII)) {
|
|
return false;
|
|
}
|
|
}
|
|
return true;
|
|
}
|
|
|
|
// Go through the packet instructions and search for anti dependency
|
|
// between them and DepReg from MI
|
|
// Consider this case:
|
|
// Trying to add
|
|
// a) %R1<def> = TFRI_cdNotPt %P3, 2
|
|
// to this packet:
|
|
// {
|
|
// b) %P0<def> = OR_pp %P3<kill>, %P0<kill>
|
|
// c) %P3<def> = TFR_PdRs %R23
|
|
// d) %R1<def> = TFRI_cdnPt %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,
|
|
const std::map<MachineInstr *, SUnit *> &MIToSUnit) {
|
|
|
|
const HexagonInstrInfo *QII = (const HexagonInstrInfo *) TII;
|
|
SUnit *PacketSUDep = MIToSUnit.find(MI)->second;
|
|
|
|
for (std::vector<MachineInstr*>::iterator VIN = CurrentPacketMIs.begin(),
|
|
VEN = CurrentPacketMIs.end(); (VIN != VEN); ++VIN) {
|
|
|
|
// We only care for dependencies to predicated instructions
|
|
if(!QII->isPredicated(*VIN)) continue;
|
|
|
|
// Scheduling Unit for current insn in the packet
|
|
SUnit *PacketSU = MIToSUnit.find(*VIN)->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) {
|
|
if ((PacketSU->Succs[i].getSUnit() == PacketSUDep) &&
|
|
(PacketSU->Succs[i].getKind() == SDep::Anti) &&
|
|
(PacketSU->Succs[i].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 (MachineInstr::mop_iterator OI = MI->operands_begin(),
|
|
OE = MI->operands_end(); OI != OE; ++OI) {
|
|
MachineOperand &Op = *OI;
|
|
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,
|
|
const std::map<MachineInstr *, SUnit *> &MIToSUnit) {
|
|
|
|
const HexagonInstrInfo *QII = (const HexagonInstrInfo *) TII;
|
|
|
|
// If we don't know the predicate sense of the instructions bail out early, we
|
|
// need it later.
|
|
if (getPredicateSense(MI1, QII) == PK_Unknown ||
|
|
getPredicateSense(MI2, QII) == PK_Unknown)
|
|
return false;
|
|
|
|
// Scheduling unit for candidate
|
|
SUnit *SU = MIToSUnit.find(MI1)->second;
|
|
|
|
// One corner case deals with the following scenario:
|
|
// Trying to add
|
|
// a) %R24<def> = TFR_cPt %P0, %R25
|
|
// to this packet:
|
|
//
|
|
// {
|
|
// b) %R25<def> = TFR_cNotPt %P0, %R24
|
|
// c) %P0<def> = CMPEQri %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 (std::vector<MachineInstr*>::iterator VIN = CurrentPacketMIs.begin(),
|
|
VEN = CurrentPacketMIs.end(); (VIN != VEN); ++VIN) {
|
|
|
|
// Scheduling Unit for current insn in the packet
|
|
SUnit *PacketSU = MIToSUnit.find(*VIN)->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) {
|
|
// 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 (PacketSU->Succs[i].getSUnit() == SU &&
|
|
PacketSU->Succs[i].getKind() == SDep::Data &&
|
|
Hexagon::PredRegsRegClass.contains(
|
|
PacketSU->Succs[i].getReg()) &&
|
|
// Here I know that *VIN 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
|
|
RestrictingDepExistInPacket(*VIN,PacketSU->Succs[i].getReg(),
|
|
MIToSUnit)) {
|
|
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 complimentary to p0.new
|
|
unsigned PReg1 = getPredicatedRegister(MI1, QII);
|
|
unsigned PReg2 = getPredicatedRegister(MI2, QII);
|
|
return ((PReg1 == PReg2) &&
|
|
Hexagon::PredRegsRegClass.contains(PReg1) &&
|
|
Hexagon::PredRegsRegClass.contains(PReg2) &&
|
|
(getPredicateSense(MI1, QII) != getPredicateSense(MI2, QII)) &&
|
|
(QII->isDotNewInst(MI1) == QII->isDotNewInst(MI2)));
|
|
}
|
|
|
|
// initPacketizerState - Initialize packetizer flags
|
|
void HexagonPacketizerList::initPacketizerState() {
|
|
|
|
Dependence = false;
|
|
PromotedToDotNew = false;
|
|
GlueToNewValueJump = false;
|
|
GlueAllocframeStore = false;
|
|
FoundSequentialDependence = false;
|
|
|
|
return;
|
|
}
|
|
|
|
// ignorePseudoInstruction - Ignore bundling of pseudo instructions.
|
|
bool HexagonPacketizerList::ignorePseudoInstruction(MachineInstr *MI,
|
|
MachineBasicBlock *MBB) {
|
|
if (MI->isDebugValue())
|
|
return true;
|
|
|
|
// We must print out inline assembly
|
|
if (MI->isInlineAsm())
|
|
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();
|
|
unsigned SchedClass = TID.getSchedClass();
|
|
const InstrStage* IS =
|
|
ResourceTracker->getInstrItins()->beginStage(SchedClass);
|
|
unsigned FuncUnits = IS->getUnits();
|
|
return !FuncUnits;
|
|
}
|
|
|
|
// isSoloInstruction: - Returns true for instructions that must be
|
|
// scheduled in their own packet.
|
|
bool HexagonPacketizerList::isSoloInstruction(MachineInstr *MI) {
|
|
|
|
if (MI->isInlineAsm())
|
|
return true;
|
|
|
|
if (MI->isEHLabel())
|
|
return true;
|
|
|
|
// From Hexagon V4 Programmer's Reference Manual 3.4.4 Grouping constraints:
|
|
// trap, pause, barrier, icinva, isync, and syncht are solo instructions.
|
|
// They must not be grouped with other instructions in a packet.
|
|
if (IsSchedBarrier(MI))
|
|
return true;
|
|
|
|
return false;
|
|
}
|
|
|
|
// isLegalToPacketizeTogether:
|
|
// 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) {
|
|
MachineInstr *I = SUI->getInstr();
|
|
MachineInstr *J = SUJ->getInstr();
|
|
assert(I && J && "Unable to packetize null instruction!");
|
|
|
|
const MCInstrDesc &MCIDI = I->getDesc();
|
|
const MCInstrDesc &MCIDJ = J->getDesc();
|
|
|
|
MachineBasicBlock::iterator II = I;
|
|
|
|
const unsigned FrameSize = MF.getFrameInfo()->getStackSize();
|
|
const HexagonRegisterInfo *QRI =
|
|
(const HexagonRegisterInfo *)MF.getSubtarget().getRegisterInfo();
|
|
const HexagonInstrInfo *QII = (const HexagonInstrInfo *) TII;
|
|
|
|
// Inline asm cannot go in the packet.
|
|
if (I->getOpcode() == Hexagon::INLINEASM)
|
|
llvm_unreachable("Should not meet inline asm here!");
|
|
|
|
if (isSoloInstruction(I))
|
|
llvm_unreachable("Should not meet solo instr here!");
|
|
|
|
// 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 ((QII->isSaveCalleeSavedRegsCall(I) &&
|
|
DoesModifyCalleeSavedReg(J, QRI)) ||
|
|
(QII->isSaveCalleeSavedRegsCall(J) &&
|
|
DoesModifyCalleeSavedReg(I, QRI))) {
|
|
Dependence = true;
|
|
return false;
|
|
}
|
|
|
|
// Two control flow instructions cannot go in the same packet.
|
|
if (IsControlFlow(I) && IsControlFlow(J)) {
|
|
Dependence = true;
|
|
return false;
|
|
}
|
|
|
|
// A LoopN instruction cannot appear in the same packet as a jump or call.
|
|
if (IsLoopN(I) &&
|
|
(IsDirectJump(J) || MCIDJ.isCall() || QII->isDeallocRet(J))) {
|
|
Dependence = true;
|
|
return false;
|
|
}
|
|
if (IsLoopN(J) &&
|
|
(IsDirectJump(I) || MCIDI.isCall() || QII->isDeallocRet(I))) {
|
|
Dependence = true;
|
|
return false;
|
|
}
|
|
|
|
// dealloc_return cannot appear in the same packet as a conditional or
|
|
// unconditional jump.
|
|
if (QII->isDeallocRet(I) &&
|
|
(MCIDJ.isBranch() || MCIDJ.isCall() || MCIDJ.isBarrier())) {
|
|
Dependence = true;
|
|
return false;
|
|
}
|
|
|
|
|
|
// V4 allows dual store. But 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
|
|
if (QRI->Subtarget.hasV4TOps()) {
|
|
if (MCIDI.mayStore() && MCIDJ.mayStore() &&
|
|
(QII->isNewValueInst(J) || QII->isMemOp(J) || QII->isMemOp(I))) {
|
|
Dependence = true;
|
|
return false;
|
|
}
|
|
|
|
if ((QII->isMemOp(J) && MCIDI.mayStore())
|
|
|| (MCIDJ.mayStore() && QII->isMemOp(I))
|
|
|| (QII->isMemOp(J) && QII->isMemOp(I))) {
|
|
Dependence = true;
|
|
return false;
|
|
}
|
|
|
|
//if dealloc_return
|
|
if (MCIDJ.mayStore() && QII->isDeallocRet(I)) {
|
|
Dependence = true;
|
|
return false;
|
|
}
|
|
|
|
// If an instruction feeds new value jump, glue it.
|
|
MachineBasicBlock::iterator NextMII = I;
|
|
++NextMII;
|
|
if (NextMII != I->getParent()->end() && QII->isNewValueJump(NextMII)) {
|
|
MachineInstr *NextMI = NextMII;
|
|
|
|
bool secondRegMatch = false;
|
|
bool maintainNewValueJump = false;
|
|
|
|
if (NextMI->getOperand(1).isReg() &&
|
|
I->getOperand(0).getReg() == NextMI->getOperand(1).getReg()) {
|
|
secondRegMatch = true;
|
|
maintainNewValueJump = true;
|
|
}
|
|
|
|
if (!secondRegMatch &&
|
|
I->getOperand(0).getReg() == NextMI->getOperand(0).getReg()) {
|
|
maintainNewValueJump = true;
|
|
}
|
|
|
|
for (std::vector<MachineInstr*>::iterator
|
|
VI = CurrentPacketMIs.begin(),
|
|
VE = CurrentPacketMIs.end();
|
|
(VI != VE && maintainNewValueJump); ++VI) {
|
|
SUnit *PacketSU = MIToSUnit.find(*VI)->second;
|
|
|
|
// NVJ can not be part of the dual jump - Arch Spec: section 7.8
|
|
if (PacketSU->getInstr()->getDesc().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 (PacketSU->getInstr()->getDesc().mayStore() ||
|
|
PacketSU->getInstr()->getOpcode() == Hexagon::ALLOCFRAME ||
|
|
// Check #2.
|
|
(!secondRegMatch && NextMI->getOperand(1).isReg() &&
|
|
PacketSU->getInstr()->modifiesRegister(
|
|
NextMI->getOperand(1).getReg(), QRI)) ||
|
|
// Check #3.
|
|
(secondRegMatch &&
|
|
PacketSU->getInstr()->modifiesRegister(
|
|
NextMI->getOperand(0).getReg(), QRI))) {
|
|
Dependence = true;
|
|
break;
|
|
}
|
|
}
|
|
if (!Dependence)
|
|
GlueToNewValueJump = true;
|
|
else
|
|
return false;
|
|
}
|
|
}
|
|
|
|
if (SUJ->isSucc(SUI)) {
|
|
for (unsigned i = 0;
|
|
(i < SUJ->Succs.size()) && !FoundSequentialDependence;
|
|
++i) {
|
|
|
|
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).
|
|
//
|
|
// TODO: Currently, jumpr is handling only return of r31. So, the
|
|
// following logic (specificaly IsCallDependent) is working fine.
|
|
// We need to enable jumpr for register other than r31 and then,
|
|
// we need to rework the last part, where it handles indirect call
|
|
// of that (IsCallDependent) function. Bug 6216 is opened for this.
|
|
//
|
|
unsigned DepReg = 0;
|
|
const TargetRegisterClass* RC = nullptr;
|
|
if (DepType == SDep::Data) {
|
|
DepReg = SUJ->Succs[i].getReg();
|
|
RC = QRI->getMinimalPhysRegClass(DepReg);
|
|
}
|
|
if ((MCIDI.isCall() || MCIDI.isReturn()) &&
|
|
(!IsRegDependence(DepType) ||
|
|
!IsCallDependent(I, DepType, SUJ->Succs[i].getReg()))) {
|
|
/* do nothing */
|
|
}
|
|
|
|
// For instructions that can be promoted to dot-new, try to promote.
|
|
else if ((DepType == SDep::Data) &&
|
|
CanPromoteToDotNew(I, SUJ, DepReg, MIToSUnit, II, RC) &&
|
|
PromoteToDotNew(I, DepType, II, RC)) {
|
|
PromotedToDotNew = true;
|
|
/* do nothing */
|
|
}
|
|
|
|
else if ((DepType == SDep::Data) &&
|
|
(QII->isNewValueJump(I))) {
|
|
/* do nothing */
|
|
}
|
|
|
|
// For predicated instructions, if the predicates are complements
|
|
// then there can be no dependence.
|
|
else if (QII->isPredicated(I) &&
|
|
QII->isPredicated(J) &&
|
|
ArePredicatesComplements(I, J, MIToSUnit)) {
|
|
/* do nothing */
|
|
|
|
}
|
|
else if (IsDirectJump(I) &&
|
|
!MCIDJ.isBranch() &&
|
|
!MCIDJ.isCall() &&
|
|
(DepType == SDep::Order)) {
|
|
// Ignore Order dependences between unconditional direct branches
|
|
// and non-control-flow instructions
|
|
/* do nothing */
|
|
}
|
|
else if (MCIDI.isConditionalBranch() && (DepType != SDep::Data) &&
|
|
(DepType != SDep::Output)) {
|
|
// Ignore all dependences for jumps except for true and output
|
|
// dependences
|
|
/* do nothing */
|
|
}
|
|
|
|
// Ignore output dependences due to superregs. We can
|
|
// write to two different subregisters of R1:0 for instance
|
|
// in the same cycle
|
|
//
|
|
|
|
//
|
|
// Let the
|
|
// If neither I nor J defines DepReg, then this is a
|
|
// superfluous output dependence. The dependence must be of the
|
|
// form:
|
|
// R0 = ...
|
|
// R1 = ...
|
|
// and there is an output dependence between the two instructions
|
|
// with
|
|
// DepReg = D0
|
|
// We want to ignore these dependences.
|
|
// Ideally, the dependence constructor should annotate such
|
|
// dependences. We can then avoid this relatively expensive check.
|
|
//
|
|
else if (DepType == SDep::Output) {
|
|
// DepReg is the register that's responsible for the dependence.
|
|
unsigned DepReg = SUJ->Succs[i].getReg();
|
|
|
|
// Check if I and J really defines DepReg.
|
|
if (I->definesRegister(DepReg) ||
|
|
J->definesRegister(DepReg)) {
|
|
FoundSequentialDependence = true;
|
|
break;
|
|
}
|
|
}
|
|
|
|
// We ignore Order dependences for
|
|
// 1. Two loads unless they are volatile.
|
|
// 2. Two stores in V4 unless they are volatile.
|
|
else if ((DepType == SDep::Order) &&
|
|
!I->hasOrderedMemoryRef() &&
|
|
!J->hasOrderedMemoryRef()) {
|
|
if (QRI->Subtarget.hasV4TOps() &&
|
|
// hexagonv4 allows dual store.
|
|
MCIDI.mayStore() && MCIDJ.mayStore()) {
|
|
/* do nothing */
|
|
}
|
|
// store followed by store-- not OK on V2
|
|
// store followed by load -- not OK on all (OK if addresses
|
|
// are not aliased)
|
|
// load followed by store -- OK on all
|
|
// load followed by load -- OK on all
|
|
else if ( !MCIDJ.mayStore()) {
|
|
/* do nothing */
|
|
}
|
|
else {
|
|
FoundSequentialDependence = true;
|
|
break;
|
|
}
|
|
}
|
|
|
|
// For V4, special case 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
|
|
// caller's SP. Hence, offset needs to be updated accordingly.
|
|
else if (DepType == SDep::Data
|
|
&& QRI->Subtarget.hasV4TOps()
|
|
&& J->getOpcode() == Hexagon::ALLOCFRAME
|
|
&& (I->getOpcode() == Hexagon::STrid
|
|
|| I->getOpcode() == Hexagon::STriw
|
|
|| I->getOpcode() == Hexagon::STrib)
|
|
&& I->getOperand(0).getReg() == QRI->getStackRegister()
|
|
&& QII->isValidOffset(I->getOpcode(),
|
|
I->getOperand(1).getImm() -
|
|
(FrameSize + HEXAGON_LRFP_SIZE)))
|
|
{
|
|
GlueAllocframeStore = true;
|
|
// 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.
|
|
I->getOperand(1).setImm(I->getOperand(1).getImm() -
|
|
(FrameSize + HEXAGON_LRFP_SIZE));
|
|
}
|
|
|
|
//
|
|
// Skip over anti-dependences. Two instructions that are
|
|
// anti-dependent can share a packet
|
|
//
|
|
else if (DepType != SDep::Anti) {
|
|
FoundSequentialDependence = true;
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (FoundSequentialDependence) {
|
|
Dependence = true;
|
|
return false;
|
|
}
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
// isLegalToPruneDependencies
|
|
bool HexagonPacketizerList::isLegalToPruneDependencies(SUnit *SUI, SUnit *SUJ) {
|
|
MachineInstr *I = SUI->getInstr();
|
|
assert(I && SUJ->getInstr() && "Unable to packetize null instruction!");
|
|
|
|
const unsigned FrameSize = MF.getFrameInfo()->getStackSize();
|
|
|
|
if (Dependence) {
|
|
|
|
// Check if the instruction was promoted to a dot-new. If so, demote it
|
|
// back into a dot-old.
|
|
if (PromotedToDotNew) {
|
|
DemoteToDotOld(I);
|
|
}
|
|
|
|
// 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
|
|
// curent SP instead of caller's SP.
|
|
if (GlueAllocframeStore) {
|
|
I->getOperand(1).setImm(I->getOperand(1).getImm() +
|
|
FrameSize + HEXAGON_LRFP_SIZE);
|
|
}
|
|
|
|
return false;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
MachineBasicBlock::iterator
|
|
HexagonPacketizerList::addToPacket(MachineInstr *MI) {
|
|
|
|
MachineBasicBlock::iterator MII = MI;
|
|
MachineBasicBlock *MBB = MI->getParent();
|
|
|
|
const HexagonInstrInfo *QII = (const HexagonInstrInfo *) TII;
|
|
|
|
if (GlueToNewValueJump) {
|
|
|
|
++MII;
|
|
MachineInstr *nvjMI = MII;
|
|
assert(ResourceTracker->canReserveResources(MI));
|
|
ResourceTracker->reserveResources(MI);
|
|
if ((QII->isExtended(MI) || QII->isConstExtended(MI)) &&
|
|
!tryAllocateResourcesForConstExt(MI)) {
|
|
endPacket(MBB, MI);
|
|
ResourceTracker->reserveResources(MI);
|
|
assert(canReserveResourcesForConstExt(MI) &&
|
|
"Ensure that there is a slot");
|
|
reserveResourcesForConstExt(MI);
|
|
// Reserve resources for new value jump constant extender.
|
|
assert(canReserveResourcesForConstExt(MI) &&
|
|
"Ensure that there is a slot");
|
|
reserveResourcesForConstExt(nvjMI);
|
|
assert(ResourceTracker->canReserveResources(nvjMI) &&
|
|
"Ensure that there is a slot");
|
|
|
|
} else if ( // Extended instruction takes two slots in the packet.
|
|
// Try reserve and allocate 4-byte in the current packet first.
|
|
(QII->isExtended(nvjMI)
|
|
&& (!tryAllocateResourcesForConstExt(nvjMI)
|
|
|| !ResourceTracker->canReserveResources(nvjMI)))
|
|
|| // For non-extended instruction, no need to allocate extra 4 bytes.
|
|
(!QII->isExtended(nvjMI) &&
|
|
!ResourceTracker->canReserveResources(nvjMI)))
|
|
{
|
|
endPacket(MBB, MI);
|
|
// A new and empty packet starts.
|
|
// We are sure that the resources requirements can be satisfied.
|
|
// Therefore, do not need to call "canReserveResources" anymore.
|
|
ResourceTracker->reserveResources(MI);
|
|
if (QII->isExtended(nvjMI))
|
|
reserveResourcesForConstExt(nvjMI);
|
|
}
|
|
// Here, we are sure that "reserveResources" would succeed.
|
|
ResourceTracker->reserveResources(nvjMI);
|
|
CurrentPacketMIs.push_back(MI);
|
|
CurrentPacketMIs.push_back(nvjMI);
|
|
} else {
|
|
if ( (QII->isExtended(MI) || QII->isConstExtended(MI))
|
|
&& ( !tryAllocateResourcesForConstExt(MI)
|
|
|| !ResourceTracker->canReserveResources(MI)))
|
|
{
|
|
endPacket(MBB, MI);
|
|
// Check if the instruction was promoted to a dot-new. If so, demote it
|
|
// back into a dot-old
|
|
if (PromotedToDotNew) {
|
|
DemoteToDotOld(MI);
|
|
}
|
|
reserveResourcesForConstExt(MI);
|
|
}
|
|
// In case that "MI" is not an extended insn,
|
|
// the resource availability has already been checked.
|
|
ResourceTracker->reserveResources(MI);
|
|
CurrentPacketMIs.push_back(MI);
|
|
}
|
|
return MII;
|
|
}
|
|
|
|
//===----------------------------------------------------------------------===//
|
|
// Public Constructor Functions
|
|
//===----------------------------------------------------------------------===//
|
|
|
|
FunctionPass *llvm::createHexagonPacketizer() {
|
|
return new HexagonPacketizer();
|
|
}
|
|
|