891 lines
32 KiB
C++
891 lines
32 KiB
C++
//===------- HexagonCopyToCombine.cpp - Hexagon Copy-To-Combine Pass ------===//
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//
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// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
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// See https://llvm.org/LICENSE.txt for license information.
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// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
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//
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//===----------------------------------------------------------------------===//
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// This pass replaces transfer instructions by combine instructions.
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// We walk along a basic block and look for two combinable instructions and try
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// to move them together. If we can move them next to each other we do so and
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// replace them with a combine instruction.
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//===----------------------------------------------------------------------===//
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#include "HexagonInstrInfo.h"
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#include "HexagonSubtarget.h"
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#include "llvm/ADT/DenseMap.h"
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#include "llvm/ADT/DenseSet.h"
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#include "llvm/CodeGen/MachineBasicBlock.h"
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#include "llvm/CodeGen/MachineFunction.h"
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#include "llvm/CodeGen/MachineFunctionPass.h"
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#include "llvm/CodeGen/MachineInstr.h"
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#include "llvm/CodeGen/MachineInstrBuilder.h"
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#include "llvm/CodeGen/Passes.h"
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#include "llvm/CodeGen/TargetRegisterInfo.h"
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#include "llvm/Pass.h"
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#include "llvm/Support/CodeGen.h"
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#include "llvm/Support/CommandLine.h"
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#include "llvm/Support/Debug.h"
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#include "llvm/Support/raw_ostream.h"
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#include "llvm/Target/TargetMachine.h"
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using namespace llvm;
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#define DEBUG_TYPE "hexagon-copy-combine"
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static
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cl::opt<bool> IsCombinesDisabled("disable-merge-into-combines",
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cl::Hidden, cl::ZeroOrMore,
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cl::init(false),
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cl::desc("Disable merging into combines"));
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static
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cl::opt<bool> IsConst64Disabled("disable-const64",
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cl::Hidden, cl::ZeroOrMore,
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cl::init(false),
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cl::desc("Disable generation of const64"));
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static
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cl::opt<unsigned>
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MaxNumOfInstsBetweenNewValueStoreAndTFR("max-num-inst-between-tfr-and-nv-store",
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cl::Hidden, cl::init(4),
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cl::desc("Maximum distance between a tfr feeding a store we "
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"consider the store still to be newifiable"));
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namespace llvm {
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FunctionPass *createHexagonCopyToCombine();
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void initializeHexagonCopyToCombinePass(PassRegistry&);
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}
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namespace {
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class HexagonCopyToCombine : public MachineFunctionPass {
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const HexagonInstrInfo *TII;
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const TargetRegisterInfo *TRI;
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const HexagonSubtarget *ST;
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bool ShouldCombineAggressively;
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DenseSet<MachineInstr *> PotentiallyNewifiableTFR;
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SmallVector<MachineInstr *, 8> DbgMItoMove;
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public:
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static char ID;
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HexagonCopyToCombine() : MachineFunctionPass(ID) {
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initializeHexagonCopyToCombinePass(*PassRegistry::getPassRegistry());
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}
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void getAnalysisUsage(AnalysisUsage &AU) const override {
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MachineFunctionPass::getAnalysisUsage(AU);
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}
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StringRef getPassName() const override {
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return "Hexagon Copy-To-Combine Pass";
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}
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bool runOnMachineFunction(MachineFunction &Fn) override;
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MachineFunctionProperties getRequiredProperties() const override {
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return MachineFunctionProperties().set(
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MachineFunctionProperties::Property::NoVRegs);
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}
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private:
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MachineInstr *findPairable(MachineInstr &I1, bool &DoInsertAtI1,
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bool AllowC64);
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void findPotentialNewifiableTFRs(MachineBasicBlock &);
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void combine(MachineInstr &I1, MachineInstr &I2,
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MachineBasicBlock::iterator &MI, bool DoInsertAtI1,
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bool OptForSize);
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bool isSafeToMoveTogether(MachineInstr &I1, MachineInstr &I2,
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unsigned I1DestReg, unsigned I2DestReg,
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bool &DoInsertAtI1);
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void emitCombineRR(MachineBasicBlock::iterator &Before, unsigned DestReg,
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MachineOperand &HiOperand, MachineOperand &LoOperand);
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void emitCombineRI(MachineBasicBlock::iterator &Before, unsigned DestReg,
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MachineOperand &HiOperand, MachineOperand &LoOperand);
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void emitCombineIR(MachineBasicBlock::iterator &Before, unsigned DestReg,
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MachineOperand &HiOperand, MachineOperand &LoOperand);
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void emitCombineII(MachineBasicBlock::iterator &Before, unsigned DestReg,
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MachineOperand &HiOperand, MachineOperand &LoOperand);
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void emitConst64(MachineBasicBlock::iterator &Before, unsigned DestReg,
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MachineOperand &HiOperand, MachineOperand &LoOperand);
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};
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} // End anonymous namespace.
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char HexagonCopyToCombine::ID = 0;
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INITIALIZE_PASS(HexagonCopyToCombine, "hexagon-copy-combine",
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"Hexagon Copy-To-Combine Pass", false, false)
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static bool isCombinableInstType(MachineInstr &MI, const HexagonInstrInfo *TII,
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bool ShouldCombineAggressively) {
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switch (MI.getOpcode()) {
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case Hexagon::A2_tfr: {
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// A COPY instruction can be combined if its arguments are IntRegs (32bit).
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const MachineOperand &Op0 = MI.getOperand(0);
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const MachineOperand &Op1 = MI.getOperand(1);
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assert(Op0.isReg() && Op1.isReg());
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Register DestReg = Op0.getReg();
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Register SrcReg = Op1.getReg();
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return Hexagon::IntRegsRegClass.contains(DestReg) &&
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Hexagon::IntRegsRegClass.contains(SrcReg);
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}
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case Hexagon::A2_tfrsi: {
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// A transfer-immediate can be combined if its argument is a signed 8bit
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// value.
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const MachineOperand &Op0 = MI.getOperand(0);
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const MachineOperand &Op1 = MI.getOperand(1);
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assert(Op0.isReg());
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Register DestReg = Op0.getReg();
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// Ensure that TargetFlags are MO_NO_FLAG for a global. This is a
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// workaround for an ABI bug that prevents GOT relocations on combine
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// instructions
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if (!Op1.isImm() && Op1.getTargetFlags() != HexagonII::MO_NO_FLAG)
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return false;
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// Only combine constant extended A2_tfrsi if we are in aggressive mode.
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bool NotExt = Op1.isImm() && isInt<8>(Op1.getImm());
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return Hexagon::IntRegsRegClass.contains(DestReg) &&
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(ShouldCombineAggressively || NotExt);
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}
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case Hexagon::V6_vassign:
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return true;
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default:
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break;
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}
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return false;
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}
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template <unsigned N> static bool isGreaterThanNBitTFRI(const MachineInstr &I) {
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if (I.getOpcode() == Hexagon::TFRI64_V4 ||
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I.getOpcode() == Hexagon::A2_tfrsi) {
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const MachineOperand &Op = I.getOperand(1);
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return !Op.isImm() || !isInt<N>(Op.getImm());
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}
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return false;
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}
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/// areCombinableOperations - Returns true if the two instruction can be merge
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/// into a combine (ignoring register constraints).
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static bool areCombinableOperations(const TargetRegisterInfo *TRI,
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MachineInstr &HighRegInst,
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MachineInstr &LowRegInst, bool AllowC64) {
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unsigned HiOpc = HighRegInst.getOpcode();
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unsigned LoOpc = LowRegInst.getOpcode();
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auto verifyOpc = [](unsigned Opc) -> void {
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switch (Opc) {
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case Hexagon::A2_tfr:
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case Hexagon::A2_tfrsi:
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case Hexagon::V6_vassign:
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break;
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default:
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llvm_unreachable("Unexpected opcode");
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}
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};
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verifyOpc(HiOpc);
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verifyOpc(LoOpc);
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if (HiOpc == Hexagon::V6_vassign || LoOpc == Hexagon::V6_vassign)
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return HiOpc == LoOpc;
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if (!AllowC64) {
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// There is no combine of two constant extended values.
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if (isGreaterThanNBitTFRI<8>(HighRegInst) &&
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isGreaterThanNBitTFRI<6>(LowRegInst))
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return false;
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}
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// There is a combine of two constant extended values into CONST64,
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// provided both constants are true immediates.
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if (isGreaterThanNBitTFRI<16>(HighRegInst) &&
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isGreaterThanNBitTFRI<16>(LowRegInst) && !IsConst64Disabled)
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return (HighRegInst.getOperand(1).isImm() &&
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LowRegInst.getOperand(1).isImm());
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// There is no combine of two constant extended values, unless handled above
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// Make both 8-bit size checks to allow both combine (#,##) and combine(##,#)
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if (isGreaterThanNBitTFRI<8>(HighRegInst) &&
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isGreaterThanNBitTFRI<8>(LowRegInst))
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return false;
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return true;
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}
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static bool isEvenReg(unsigned Reg) {
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assert(Register::isPhysicalRegister(Reg));
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if (Hexagon::IntRegsRegClass.contains(Reg))
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return (Reg - Hexagon::R0) % 2 == 0;
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if (Hexagon::HvxVRRegClass.contains(Reg))
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return (Reg - Hexagon::V0) % 2 == 0;
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llvm_unreachable("Invalid register");
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}
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static void removeKillInfo(MachineInstr &MI, unsigned RegNotKilled) {
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for (unsigned I = 0, E = MI.getNumOperands(); I != E; ++I) {
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MachineOperand &Op = MI.getOperand(I);
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if (!Op.isReg() || Op.getReg() != RegNotKilled || !Op.isKill())
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continue;
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Op.setIsKill(false);
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}
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}
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/// Returns true if it is unsafe to move a copy instruction from \p UseReg to
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/// \p DestReg over the instruction \p MI.
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static bool isUnsafeToMoveAcross(MachineInstr &MI, unsigned UseReg,
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unsigned DestReg,
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const TargetRegisterInfo *TRI) {
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return (UseReg && (MI.modifiesRegister(UseReg, TRI))) ||
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MI.modifiesRegister(DestReg, TRI) || MI.readsRegister(DestReg, TRI) ||
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MI.hasUnmodeledSideEffects() || MI.isInlineAsm() ||
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MI.isMetaInstruction();
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}
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static Register UseReg(const MachineOperand& MO) {
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return MO.isReg() ? MO.getReg() : Register();
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}
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/// isSafeToMoveTogether - Returns true if it is safe to move I1 next to I2 such
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/// that the two instructions can be paired in a combine.
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bool HexagonCopyToCombine::isSafeToMoveTogether(MachineInstr &I1,
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MachineInstr &I2,
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unsigned I1DestReg,
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unsigned I2DestReg,
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bool &DoInsertAtI1) {
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Register I2UseReg = UseReg(I2.getOperand(1));
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// It is not safe to move I1 and I2 into one combine if I2 has a true
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// dependence on I1.
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if (I2UseReg && I1.modifiesRegister(I2UseReg, TRI))
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return false;
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bool isSafe = true;
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// First try to move I2 towards I1.
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{
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// A reverse_iterator instantiated like below starts before I2, and I1
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// respectively.
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// Look at instructions I in between I2 and (excluding) I1.
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MachineBasicBlock::reverse_iterator I = ++I2.getIterator().getReverse();
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MachineBasicBlock::reverse_iterator End = I1.getIterator().getReverse();
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// At 03 we got better results (dhrystone!) by being more conservative.
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if (!ShouldCombineAggressively)
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End = ++I1.getIterator().getReverse();
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// If I2 kills its operand and we move I2 over an instruction that also
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// uses I2's use reg we need to modify that (first) instruction to now kill
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// this reg.
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unsigned KilledOperand = 0;
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if (I2.killsRegister(I2UseReg))
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KilledOperand = I2UseReg;
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MachineInstr *KillingInstr = nullptr;
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for (; I != End; ++I) {
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// If the intervening instruction I:
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// * modifies I2's use reg
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// * modifies I2's def reg
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// * reads I2's def reg
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// * or has unmodelled side effects
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// we can't move I2 across it.
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if (I->isDebugInstr())
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continue;
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if (isUnsafeToMoveAcross(*I, I2UseReg, I2DestReg, TRI)) {
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isSafe = false;
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break;
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}
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// Update first use of the killed operand.
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if (!KillingInstr && KilledOperand &&
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I->readsRegister(KilledOperand, TRI))
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KillingInstr = &*I;
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}
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if (isSafe) {
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// Update the intermediate instruction to with the kill flag.
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if (KillingInstr) {
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bool Added = KillingInstr->addRegisterKilled(KilledOperand, TRI, true);
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(void)Added; // suppress compiler warning
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assert(Added && "Must successfully update kill flag");
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removeKillInfo(I2, KilledOperand);
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}
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DoInsertAtI1 = true;
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return true;
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}
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}
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// Try to move I1 towards I2.
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{
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// Look at instructions I in between I1 and (excluding) I2.
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MachineBasicBlock::iterator I(I1), End(I2);
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// At O3 we got better results (dhrystone) by being more conservative here.
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if (!ShouldCombineAggressively)
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End = std::next(MachineBasicBlock::iterator(I2));
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Register I1UseReg = UseReg(I1.getOperand(1));
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// Track killed operands. If we move across an instruction that kills our
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// operand, we need to update the kill information on the moved I1. It kills
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// the operand now.
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MachineInstr *KillingInstr = nullptr;
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unsigned KilledOperand = 0;
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while(++I != End) {
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MachineInstr &MI = *I;
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// If the intervening instruction MI:
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// * modifies I1's use reg
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// * modifies I1's def reg
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// * reads I1's def reg
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// * or has unmodelled side effects
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// We introduce this special case because llvm has no api to remove a
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// kill flag for a register (a removeRegisterKilled() analogous to
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// addRegisterKilled) that handles aliased register correctly.
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// * or has a killed aliased register use of I1's use reg
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// %d4 = A2_tfrpi 16
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// %r6 = A2_tfr %r9
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// %r8 = KILL %r8, implicit killed %d4
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// If we want to move R6 = across the KILL instruction we would have
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// to remove the implicit killed %d4 operand. For now, we are
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// conservative and disallow the move.
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// we can't move I1 across it.
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if (MI.isDebugInstr()) {
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if (MI.readsRegister(I1DestReg, TRI)) // Move this instruction after I2.
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DbgMItoMove.push_back(&MI);
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continue;
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}
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if (isUnsafeToMoveAcross(MI, I1UseReg, I1DestReg, TRI) ||
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// Check for an aliased register kill. Bail out if we see one.
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(!MI.killsRegister(I1UseReg) && MI.killsRegister(I1UseReg, TRI)))
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return false;
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// Check for an exact kill (registers match).
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if (I1UseReg && MI.killsRegister(I1UseReg)) {
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assert(!KillingInstr && "Should only see one killing instruction");
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KilledOperand = I1UseReg;
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KillingInstr = &MI;
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}
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}
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if (KillingInstr) {
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removeKillInfo(*KillingInstr, KilledOperand);
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// Update I1 to set the kill flag. This flag will later be picked up by
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// the new COMBINE instruction.
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bool Added = I1.addRegisterKilled(KilledOperand, TRI);
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(void)Added; // suppress compiler warning
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assert(Added && "Must successfully update kill flag");
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}
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DoInsertAtI1 = false;
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}
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return true;
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}
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/// findPotentialNewifiableTFRs - Finds tranfers that feed stores that could be
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/// newified. (A use of a 64 bit register define can not be newified)
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void
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HexagonCopyToCombine::findPotentialNewifiableTFRs(MachineBasicBlock &BB) {
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DenseMap<unsigned, MachineInstr *> LastDef;
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for (MachineInstr &MI : BB) {
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if (MI.isDebugInstr())
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continue;
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// Mark TFRs that feed a potential new value store as such.
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if (TII->mayBeNewStore(MI)) {
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// Look for uses of TFR instructions.
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for (unsigned OpdIdx = 0, OpdE = MI.getNumOperands(); OpdIdx != OpdE;
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++OpdIdx) {
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MachineOperand &Op = MI.getOperand(OpdIdx);
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// Skip over anything except register uses.
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if (!Op.isReg() || !Op.isUse() || !Op.getReg())
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continue;
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// Look for the defining instruction.
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Register Reg = Op.getReg();
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MachineInstr *DefInst = LastDef[Reg];
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if (!DefInst)
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continue;
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if (!isCombinableInstType(*DefInst, TII, ShouldCombineAggressively))
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continue;
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// Only close newifiable stores should influence the decision.
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// Ignore the debug instructions in between.
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MachineBasicBlock::iterator It(DefInst);
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unsigned NumInstsToDef = 0;
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while (&*It != &MI) {
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if (!It->isDebugInstr())
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++NumInstsToDef;
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++It;
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}
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if (NumInstsToDef > MaxNumOfInstsBetweenNewValueStoreAndTFR)
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continue;
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PotentiallyNewifiableTFR.insert(DefInst);
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}
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// Skip to next instruction.
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continue;
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}
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// Put instructions that last defined integer or double registers into the
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// map.
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for (MachineOperand &Op : MI.operands()) {
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if (Op.isReg()) {
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if (!Op.isDef() || !Op.getReg())
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continue;
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Register Reg = Op.getReg();
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if (Hexagon::DoubleRegsRegClass.contains(Reg)) {
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for (MCSubRegIterator SubRegs(Reg, TRI); SubRegs.isValid(); ++SubRegs)
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LastDef[*SubRegs] = &MI;
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} else if (Hexagon::IntRegsRegClass.contains(Reg))
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LastDef[Reg] = &MI;
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} else if (Op.isRegMask()) {
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for (unsigned Reg : Hexagon::IntRegsRegClass)
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if (Op.clobbersPhysReg(Reg))
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LastDef[Reg] = &MI;
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}
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}
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}
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}
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bool HexagonCopyToCombine::runOnMachineFunction(MachineFunction &MF) {
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if (skipFunction(MF.getFunction()))
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return false;
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if (IsCombinesDisabled) return false;
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bool HasChanged = false;
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// Get target info.
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ST = &MF.getSubtarget<HexagonSubtarget>();
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TRI = ST->getRegisterInfo();
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TII = ST->getInstrInfo();
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const Function &F = MF.getFunction();
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bool OptForSize = F.hasFnAttribute(Attribute::OptimizeForSize);
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// Combine aggressively (for code size)
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ShouldCombineAggressively =
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MF.getTarget().getOptLevel() <= CodeGenOpt::Default;
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// Disable CONST64 for tiny core since it takes a LD resource.
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if (!OptForSize && ST->isTinyCore())
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IsConst64Disabled = true;
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// Traverse basic blocks.
|
|
for (MachineFunction::iterator BI = MF.begin(), BE = MF.end(); BI != BE;
|
|
++BI) {
|
|
PotentiallyNewifiableTFR.clear();
|
|
findPotentialNewifiableTFRs(*BI);
|
|
|
|
// Traverse instructions in basic block.
|
|
for(MachineBasicBlock::iterator MI = BI->begin(), End = BI->end();
|
|
MI != End;) {
|
|
MachineInstr &I1 = *MI++;
|
|
|
|
if (I1.isDebugInstr())
|
|
continue;
|
|
|
|
// Don't combine a TFR whose user could be newified (instructions that
|
|
// define double registers can not be newified - Programmer's Ref Manual
|
|
// 5.4.2 New-value stores).
|
|
if (ShouldCombineAggressively && PotentiallyNewifiableTFR.count(&I1))
|
|
continue;
|
|
|
|
// Ignore instructions that are not combinable.
|
|
if (!isCombinableInstType(I1, TII, ShouldCombineAggressively))
|
|
continue;
|
|
|
|
// Find a second instruction that can be merged into a combine
|
|
// instruction. In addition, also find all the debug instructions that
|
|
// need to be moved along with it.
|
|
bool DoInsertAtI1 = false;
|
|
DbgMItoMove.clear();
|
|
MachineInstr *I2 = findPairable(I1, DoInsertAtI1, OptForSize);
|
|
if (I2) {
|
|
HasChanged = true;
|
|
combine(I1, *I2, MI, DoInsertAtI1, OptForSize);
|
|
}
|
|
}
|
|
}
|
|
|
|
return HasChanged;
|
|
}
|
|
|
|
/// findPairable - Returns an instruction that can be merged with \p I1 into a
|
|
/// COMBINE instruction or 0 if no such instruction can be found. Returns true
|
|
/// in \p DoInsertAtI1 if the combine must be inserted at instruction \p I1
|
|
/// false if the combine must be inserted at the returned instruction.
|
|
MachineInstr *HexagonCopyToCombine::findPairable(MachineInstr &I1,
|
|
bool &DoInsertAtI1,
|
|
bool AllowC64) {
|
|
MachineBasicBlock::iterator I2 = std::next(MachineBasicBlock::iterator(I1));
|
|
while (I2 != I1.getParent()->end() && I2->isDebugInstr())
|
|
++I2;
|
|
|
|
Register I1DestReg = I1.getOperand(0).getReg();
|
|
|
|
for (MachineBasicBlock::iterator End = I1.getParent()->end(); I2 != End;
|
|
++I2) {
|
|
// Bail out early if we see a second definition of I1DestReg.
|
|
if (I2->modifiesRegister(I1DestReg, TRI))
|
|
break;
|
|
|
|
// Ignore non-combinable instructions.
|
|
if (!isCombinableInstType(*I2, TII, ShouldCombineAggressively))
|
|
continue;
|
|
|
|
// Don't combine a TFR whose user could be newified.
|
|
if (ShouldCombineAggressively && PotentiallyNewifiableTFR.count(&*I2))
|
|
continue;
|
|
|
|
Register I2DestReg = I2->getOperand(0).getReg();
|
|
|
|
// Check that registers are adjacent and that the first destination register
|
|
// is even.
|
|
bool IsI1LowReg = (I2DestReg - I1DestReg) == 1;
|
|
bool IsI2LowReg = (I1DestReg - I2DestReg) == 1;
|
|
unsigned FirstRegIndex = IsI1LowReg ? I1DestReg : I2DestReg;
|
|
if ((!IsI1LowReg && !IsI2LowReg) || !isEvenReg(FirstRegIndex))
|
|
continue;
|
|
|
|
// Check that the two instructions are combinable.
|
|
// The order matters because in a A2_tfrsi we might can encode a int8 as
|
|
// the hi reg operand but only a uint6 as the low reg operand.
|
|
if ((IsI2LowReg && !areCombinableOperations(TRI, I1, *I2, AllowC64)) ||
|
|
(IsI1LowReg && !areCombinableOperations(TRI, *I2, I1, AllowC64)))
|
|
break;
|
|
|
|
if (isSafeToMoveTogether(I1, *I2, I1DestReg, I2DestReg, DoInsertAtI1))
|
|
return &*I2;
|
|
|
|
// Not safe. Stop searching.
|
|
break;
|
|
}
|
|
return nullptr;
|
|
}
|
|
|
|
void HexagonCopyToCombine::combine(MachineInstr &I1, MachineInstr &I2,
|
|
MachineBasicBlock::iterator &MI,
|
|
bool DoInsertAtI1, bool OptForSize) {
|
|
// We are going to delete I2. If MI points to I2 advance it to the next
|
|
// instruction.
|
|
if (MI == I2.getIterator())
|
|
++MI;
|
|
|
|
// Figure out whether I1 or I2 goes into the lowreg part.
|
|
Register I1DestReg = I1.getOperand(0).getReg();
|
|
Register I2DestReg = I2.getOperand(0).getReg();
|
|
bool IsI1Loreg = (I2DestReg - I1DestReg) == 1;
|
|
unsigned LoRegDef = IsI1Loreg ? I1DestReg : I2DestReg;
|
|
unsigned SubLo;
|
|
|
|
const TargetRegisterClass *SuperRC = nullptr;
|
|
if (Hexagon::IntRegsRegClass.contains(LoRegDef)) {
|
|
SuperRC = &Hexagon::DoubleRegsRegClass;
|
|
SubLo = Hexagon::isub_lo;
|
|
} else if (Hexagon::HvxVRRegClass.contains(LoRegDef)) {
|
|
assert(ST->useHVXOps());
|
|
SuperRC = &Hexagon::HvxWRRegClass;
|
|
SubLo = Hexagon::vsub_lo;
|
|
} else
|
|
llvm_unreachable("Unexpected register class");
|
|
|
|
// Get the double word register.
|
|
unsigned DoubleRegDest = TRI->getMatchingSuperReg(LoRegDef, SubLo, SuperRC);
|
|
assert(DoubleRegDest != 0 && "Expect a valid register");
|
|
|
|
// Setup source operands.
|
|
MachineOperand &LoOperand = IsI1Loreg ? I1.getOperand(1) : I2.getOperand(1);
|
|
MachineOperand &HiOperand = IsI1Loreg ? I2.getOperand(1) : I1.getOperand(1);
|
|
|
|
// Figure out which source is a register and which a constant.
|
|
bool IsHiReg = HiOperand.isReg();
|
|
bool IsLoReg = LoOperand.isReg();
|
|
|
|
// There is a combine of two constant extended values into CONST64.
|
|
bool IsC64 = OptForSize && LoOperand.isImm() && HiOperand.isImm() &&
|
|
isGreaterThanNBitTFRI<16>(I1) && isGreaterThanNBitTFRI<16>(I2);
|
|
|
|
MachineBasicBlock::iterator InsertPt(DoInsertAtI1 ? I1 : I2);
|
|
// Emit combine.
|
|
if (IsHiReg && IsLoReg)
|
|
emitCombineRR(InsertPt, DoubleRegDest, HiOperand, LoOperand);
|
|
else if (IsHiReg)
|
|
emitCombineRI(InsertPt, DoubleRegDest, HiOperand, LoOperand);
|
|
else if (IsLoReg)
|
|
emitCombineIR(InsertPt, DoubleRegDest, HiOperand, LoOperand);
|
|
else if (IsC64 && !IsConst64Disabled)
|
|
emitConst64(InsertPt, DoubleRegDest, HiOperand, LoOperand);
|
|
else
|
|
emitCombineII(InsertPt, DoubleRegDest, HiOperand, LoOperand);
|
|
|
|
// Move debug instructions along with I1 if it's being
|
|
// moved towards I2.
|
|
if (!DoInsertAtI1 && DbgMItoMove.size() != 0) {
|
|
// Insert debug instructions at the new location before I2.
|
|
MachineBasicBlock *BB = InsertPt->getParent();
|
|
for (auto NewMI : DbgMItoMove) {
|
|
// If iterator MI is pointing to DEBUG_VAL, make sure
|
|
// MI now points to next relevant instruction.
|
|
if (NewMI == MI)
|
|
++MI;
|
|
BB->splice(InsertPt, BB, NewMI);
|
|
}
|
|
}
|
|
|
|
I1.eraseFromParent();
|
|
I2.eraseFromParent();
|
|
}
|
|
|
|
void HexagonCopyToCombine::emitConst64(MachineBasicBlock::iterator &InsertPt,
|
|
unsigned DoubleDestReg,
|
|
MachineOperand &HiOperand,
|
|
MachineOperand &LoOperand) {
|
|
LLVM_DEBUG(dbgs() << "Found a CONST64\n");
|
|
|
|
DebugLoc DL = InsertPt->getDebugLoc();
|
|
MachineBasicBlock *BB = InsertPt->getParent();
|
|
assert(LoOperand.isImm() && HiOperand.isImm() &&
|
|
"Both operands must be immediate");
|
|
|
|
int64_t V = HiOperand.getImm();
|
|
V = (V << 32) | (0x0ffffffffLL & LoOperand.getImm());
|
|
BuildMI(*BB, InsertPt, DL, TII->get(Hexagon::CONST64), DoubleDestReg)
|
|
.addImm(V);
|
|
}
|
|
|
|
void HexagonCopyToCombine::emitCombineII(MachineBasicBlock::iterator &InsertPt,
|
|
unsigned DoubleDestReg,
|
|
MachineOperand &HiOperand,
|
|
MachineOperand &LoOperand) {
|
|
DebugLoc DL = InsertPt->getDebugLoc();
|
|
MachineBasicBlock *BB = InsertPt->getParent();
|
|
|
|
// Handle globals.
|
|
if (HiOperand.isGlobal()) {
|
|
BuildMI(*BB, InsertPt, DL, TII->get(Hexagon::A2_combineii), DoubleDestReg)
|
|
.addGlobalAddress(HiOperand.getGlobal(), HiOperand.getOffset(),
|
|
HiOperand.getTargetFlags())
|
|
.addImm(LoOperand.getImm());
|
|
return;
|
|
}
|
|
if (LoOperand.isGlobal()) {
|
|
BuildMI(*BB, InsertPt, DL, TII->get(Hexagon::A4_combineii), DoubleDestReg)
|
|
.addImm(HiOperand.getImm())
|
|
.addGlobalAddress(LoOperand.getGlobal(), LoOperand.getOffset(),
|
|
LoOperand.getTargetFlags());
|
|
return;
|
|
}
|
|
|
|
// Handle block addresses.
|
|
if (HiOperand.isBlockAddress()) {
|
|
BuildMI(*BB, InsertPt, DL, TII->get(Hexagon::A2_combineii), DoubleDestReg)
|
|
.addBlockAddress(HiOperand.getBlockAddress(), HiOperand.getOffset(),
|
|
HiOperand.getTargetFlags())
|
|
.addImm(LoOperand.getImm());
|
|
return;
|
|
}
|
|
if (LoOperand.isBlockAddress()) {
|
|
BuildMI(*BB, InsertPt, DL, TII->get(Hexagon::A4_combineii), DoubleDestReg)
|
|
.addImm(HiOperand.getImm())
|
|
.addBlockAddress(LoOperand.getBlockAddress(), LoOperand.getOffset(),
|
|
LoOperand.getTargetFlags());
|
|
return;
|
|
}
|
|
|
|
// Handle jump tables.
|
|
if (HiOperand.isJTI()) {
|
|
BuildMI(*BB, InsertPt, DL, TII->get(Hexagon::A2_combineii), DoubleDestReg)
|
|
.addJumpTableIndex(HiOperand.getIndex(), HiOperand.getTargetFlags())
|
|
.addImm(LoOperand.getImm());
|
|
return;
|
|
}
|
|
if (LoOperand.isJTI()) {
|
|
BuildMI(*BB, InsertPt, DL, TII->get(Hexagon::A4_combineii), DoubleDestReg)
|
|
.addImm(HiOperand.getImm())
|
|
.addJumpTableIndex(LoOperand.getIndex(), LoOperand.getTargetFlags());
|
|
return;
|
|
}
|
|
|
|
// Handle constant pools.
|
|
if (HiOperand.isCPI()) {
|
|
BuildMI(*BB, InsertPt, DL, TII->get(Hexagon::A2_combineii), DoubleDestReg)
|
|
.addConstantPoolIndex(HiOperand.getIndex(), HiOperand.getOffset(),
|
|
HiOperand.getTargetFlags())
|
|
.addImm(LoOperand.getImm());
|
|
return;
|
|
}
|
|
if (LoOperand.isCPI()) {
|
|
BuildMI(*BB, InsertPt, DL, TII->get(Hexagon::A4_combineii), DoubleDestReg)
|
|
.addImm(HiOperand.getImm())
|
|
.addConstantPoolIndex(LoOperand.getIndex(), LoOperand.getOffset(),
|
|
LoOperand.getTargetFlags());
|
|
return;
|
|
}
|
|
|
|
// First preference should be given to Hexagon::A2_combineii instruction
|
|
// as it can include U6 (in Hexagon::A4_combineii) as well.
|
|
// In this instruction, HiOperand is const extended, if required.
|
|
if (isInt<8>(LoOperand.getImm())) {
|
|
BuildMI(*BB, InsertPt, DL, TII->get(Hexagon::A2_combineii), DoubleDestReg)
|
|
.addImm(HiOperand.getImm())
|
|
.addImm(LoOperand.getImm());
|
|
return;
|
|
}
|
|
|
|
// In this instruction, LoOperand is const extended, if required.
|
|
if (isInt<8>(HiOperand.getImm())) {
|
|
BuildMI(*BB, InsertPt, DL, TII->get(Hexagon::A4_combineii), DoubleDestReg)
|
|
.addImm(HiOperand.getImm())
|
|
.addImm(LoOperand.getImm());
|
|
return;
|
|
}
|
|
|
|
// Insert new combine instruction.
|
|
// DoubleRegDest = combine #HiImm, #LoImm
|
|
BuildMI(*BB, InsertPt, DL, TII->get(Hexagon::A2_combineii), DoubleDestReg)
|
|
.addImm(HiOperand.getImm())
|
|
.addImm(LoOperand.getImm());
|
|
}
|
|
|
|
void HexagonCopyToCombine::emitCombineIR(MachineBasicBlock::iterator &InsertPt,
|
|
unsigned DoubleDestReg,
|
|
MachineOperand &HiOperand,
|
|
MachineOperand &LoOperand) {
|
|
Register LoReg = LoOperand.getReg();
|
|
unsigned LoRegKillFlag = getKillRegState(LoOperand.isKill());
|
|
|
|
DebugLoc DL = InsertPt->getDebugLoc();
|
|
MachineBasicBlock *BB = InsertPt->getParent();
|
|
|
|
// Handle globals.
|
|
if (HiOperand.isGlobal()) {
|
|
BuildMI(*BB, InsertPt, DL, TII->get(Hexagon::A4_combineir), DoubleDestReg)
|
|
.addGlobalAddress(HiOperand.getGlobal(), HiOperand.getOffset(),
|
|
HiOperand.getTargetFlags())
|
|
.addReg(LoReg, LoRegKillFlag);
|
|
return;
|
|
}
|
|
// Handle block addresses.
|
|
if (HiOperand.isBlockAddress()) {
|
|
BuildMI(*BB, InsertPt, DL, TII->get(Hexagon::A4_combineir), DoubleDestReg)
|
|
.addBlockAddress(HiOperand.getBlockAddress(), HiOperand.getOffset(),
|
|
HiOperand.getTargetFlags())
|
|
.addReg(LoReg, LoRegKillFlag);
|
|
return;
|
|
}
|
|
// Handle jump tables.
|
|
if (HiOperand.isJTI()) {
|
|
BuildMI(*BB, InsertPt, DL, TII->get(Hexagon::A4_combineir), DoubleDestReg)
|
|
.addJumpTableIndex(HiOperand.getIndex(), HiOperand.getTargetFlags())
|
|
.addReg(LoReg, LoRegKillFlag);
|
|
return;
|
|
}
|
|
// Handle constant pools.
|
|
if (HiOperand.isCPI()) {
|
|
BuildMI(*BB, InsertPt, DL, TII->get(Hexagon::A4_combineir), DoubleDestReg)
|
|
.addConstantPoolIndex(HiOperand.getIndex(), HiOperand.getOffset(),
|
|
HiOperand.getTargetFlags())
|
|
.addReg(LoReg, LoRegKillFlag);
|
|
return;
|
|
}
|
|
// Insert new combine instruction.
|
|
// DoubleRegDest = combine #HiImm, LoReg
|
|
BuildMI(*BB, InsertPt, DL, TII->get(Hexagon::A4_combineir), DoubleDestReg)
|
|
.addImm(HiOperand.getImm())
|
|
.addReg(LoReg, LoRegKillFlag);
|
|
}
|
|
|
|
void HexagonCopyToCombine::emitCombineRI(MachineBasicBlock::iterator &InsertPt,
|
|
unsigned DoubleDestReg,
|
|
MachineOperand &HiOperand,
|
|
MachineOperand &LoOperand) {
|
|
unsigned HiRegKillFlag = getKillRegState(HiOperand.isKill());
|
|
Register HiReg = HiOperand.getReg();
|
|
|
|
DebugLoc DL = InsertPt->getDebugLoc();
|
|
MachineBasicBlock *BB = InsertPt->getParent();
|
|
|
|
// Handle global.
|
|
if (LoOperand.isGlobal()) {
|
|
BuildMI(*BB, InsertPt, DL, TII->get(Hexagon::A4_combineri), DoubleDestReg)
|
|
.addReg(HiReg, HiRegKillFlag)
|
|
.addGlobalAddress(LoOperand.getGlobal(), LoOperand.getOffset(),
|
|
LoOperand.getTargetFlags());
|
|
return;
|
|
}
|
|
// Handle block addresses.
|
|
if (LoOperand.isBlockAddress()) {
|
|
BuildMI(*BB, InsertPt, DL, TII->get(Hexagon::A4_combineri), DoubleDestReg)
|
|
.addReg(HiReg, HiRegKillFlag)
|
|
.addBlockAddress(LoOperand.getBlockAddress(), LoOperand.getOffset(),
|
|
LoOperand.getTargetFlags());
|
|
return;
|
|
}
|
|
// Handle jump tables.
|
|
if (LoOperand.isJTI()) {
|
|
BuildMI(*BB, InsertPt, DL, TII->get(Hexagon::A4_combineri), DoubleDestReg)
|
|
.addReg(HiOperand.getReg(), HiRegKillFlag)
|
|
.addJumpTableIndex(LoOperand.getIndex(), LoOperand.getTargetFlags());
|
|
return;
|
|
}
|
|
// Handle constant pools.
|
|
if (LoOperand.isCPI()) {
|
|
BuildMI(*BB, InsertPt, DL, TII->get(Hexagon::A4_combineri), DoubleDestReg)
|
|
.addReg(HiOperand.getReg(), HiRegKillFlag)
|
|
.addConstantPoolIndex(LoOperand.getIndex(), LoOperand.getOffset(),
|
|
LoOperand.getTargetFlags());
|
|
return;
|
|
}
|
|
|
|
// Insert new combine instruction.
|
|
// DoubleRegDest = combine HiReg, #LoImm
|
|
BuildMI(*BB, InsertPt, DL, TII->get(Hexagon::A4_combineri), DoubleDestReg)
|
|
.addReg(HiReg, HiRegKillFlag)
|
|
.addImm(LoOperand.getImm());
|
|
}
|
|
|
|
void HexagonCopyToCombine::emitCombineRR(MachineBasicBlock::iterator &InsertPt,
|
|
unsigned DoubleDestReg,
|
|
MachineOperand &HiOperand,
|
|
MachineOperand &LoOperand) {
|
|
unsigned LoRegKillFlag = getKillRegState(LoOperand.isKill());
|
|
unsigned HiRegKillFlag = getKillRegState(HiOperand.isKill());
|
|
Register LoReg = LoOperand.getReg();
|
|
Register HiReg = HiOperand.getReg();
|
|
|
|
DebugLoc DL = InsertPt->getDebugLoc();
|
|
MachineBasicBlock *BB = InsertPt->getParent();
|
|
|
|
// Insert new combine instruction.
|
|
// DoubleRegDest = combine HiReg, LoReg
|
|
unsigned NewOpc;
|
|
if (Hexagon::DoubleRegsRegClass.contains(DoubleDestReg)) {
|
|
NewOpc = Hexagon::A2_combinew;
|
|
} else if (Hexagon::HvxWRRegClass.contains(DoubleDestReg)) {
|
|
assert(ST->useHVXOps());
|
|
NewOpc = Hexagon::V6_vcombine;
|
|
} else
|
|
llvm_unreachable("Unexpected register");
|
|
|
|
BuildMI(*BB, InsertPt, DL, TII->get(NewOpc), DoubleDestReg)
|
|
.addReg(HiReg, HiRegKillFlag)
|
|
.addReg(LoReg, LoRegKillFlag);
|
|
}
|
|
|
|
FunctionPass *llvm::createHexagonCopyToCombine() {
|
|
return new HexagonCopyToCombine();
|
|
}
|