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package org.graalvm.compiler.lir;

import static jdk.vm.ci.code.ValueUtil.asStackSlot;
import static jdk.vm.ci.code.ValueUtil.isStackSlot;
import static org.graalvm.compiler.lir.LIRInstruction.OperandFlag.CONST;
import static org.graalvm.compiler.lir.LIRInstruction.OperandFlag.HINT;
import static org.graalvm.compiler.lir.LIRInstruction.OperandFlag.OUTGOING;
import static org.graalvm.compiler.lir.LIRInstruction.OperandFlag.REG;
import static org.graalvm.compiler.lir.LIRInstruction.OperandFlag.STACK;

import java.util.ArrayList;
import java.util.Arrays;
import java.util.EnumSet;

import jdk.internal.vm.compiler.collections.EconomicSet;
import jdk.internal.vm.compiler.collections.Equivalence;
import org.graalvm.compiler.asm.Label;
import org.graalvm.compiler.core.common.GraalOptions;
import org.graalvm.compiler.core.common.cfg.AbstractBlockBase;
import org.graalvm.compiler.debug.GraalError;
import org.graalvm.compiler.lir.asm.CompilationResultBuilder;
import org.graalvm.compiler.lir.framemap.FrameMap;

import jdk.vm.ci.code.Register;
import jdk.vm.ci.code.RegisterSaveLayout;
import jdk.vm.ci.code.StackSlot;
import jdk.vm.ci.meta.AllocatableValue;
import jdk.vm.ci.meta.Constant;
import jdk.vm.ci.meta.Value;

A collection of machine-independent LIR operations, as well as interfaces to be implemented for specific kinds or LIR operations.
/** * A collection of machine-independent LIR operations, as well as interfaces to be implemented for * specific kinds or LIR operations. */
public class StandardOp {
A block delimiter. Every well formed block must contain exactly one such operation and it must be the last operation in the block.
/** * A block delimiter. Every well formed block must contain exactly one such operation and it * must be the last operation in the block. */
public interface BlockEndOp { } public interface NullCheck { Value getCheckedValue(); LIRFrameState getState(); } public interface ImplicitNullCheck { boolean makeNullCheckFor(Value value, LIRFrameState nullCheckState, int implicitNullCheckLimit); } public interface LabelHoldingOp { Label getLabel(); }
LIR operation that defines the position of a label.
/** * LIR operation that defines the position of a label. */
public static final class LabelOp extends LIRInstruction implements LabelHoldingOp { public static final LIRInstructionClass<LabelOp> TYPE = LIRInstructionClass.create(LabelOp.class); public static final EnumSet<OperandFlag> incomingFlags = EnumSet.of(REG, STACK);
In the LIR, every register and variable must be defined before it is used. For method parameters that are passed in fixed registers, exception objects passed to the exception handler in a fixed register, or any other use of a fixed register not defined in this method, an artificial definition is necessary. To avoid spill moves to be inserted between the label at the beginning of a block an an actual definition in the second instruction of a block, the registers are defined here in the label.
/** * In the LIR, every register and variable must be defined before it is used. For method * parameters that are passed in fixed registers, exception objects passed to the exception * handler in a fixed register, or any other use of a fixed register not defined in this * method, an artificial definition is necessary. To avoid spill moves to be inserted * between the label at the beginning of a block an an actual definition in the second * instruction of a block, the registers are defined here in the label. */
@Def({REG, STACK}) private Value[] incomingValues; private final Label label; private final boolean align; private int numbPhis; public LabelOp(Label label, boolean align) { super(TYPE); this.label = label; this.align = align; this.incomingValues = Value.NO_VALUES; this.numbPhis = 0; } public void setPhiValues(Value[] values) { setIncomingValues(values); setNumberOfPhis(values.length); } private void setNumberOfPhis(int numPhis) { assert numbPhis == 0; numbPhis = numPhis; } public int getPhiSize() { return numbPhis; } public void setIncomingValues(Value[] values) { assert this.incomingValues.length == 0; assert values != null; this.incomingValues = values; } public int getIncomingSize() { return incomingValues.length; } public Value getIncomingValue(int idx) { assert checkRange(idx); return incomingValues[idx]; } public void clearIncomingValues() { incomingValues = Value.NO_VALUES; } public void addIncomingValues(Value[] values) { if (incomingValues.length == 0) { setIncomingValues(values); return; } int t = incomingValues.length + values.length; Value[] newArray = new Value[t]; System.arraycopy(incomingValues, 0, newArray, 0, incomingValues.length); System.arraycopy(values, 0, newArray, incomingValues.length, values.length); incomingValues = newArray; } private boolean checkRange(int idx) { return idx < incomingValues.length; } @Override public void emitCode(CompilationResultBuilder crb) { if (align) { crb.asm.align(GraalOptions.LoopHeaderAlignment.getValue(crb.getOptions())); } crb.asm.bind(label); } @Override public Label getLabel() { return label; }
Returns:true if this label acts as a PhiIn.
/** * @return true if this label acts as a PhiIn. */
public boolean isPhiIn() { return getPhiSize() > 0; } public void forEachIncomingValue(InstructionValueProcedure proc) { for (int i = 0; i < incomingValues.length; i++) { incomingValues[i] = proc.doValue(this, incomingValues[i], OperandMode.DEF, incomingFlags); } } }
LIR operation that is an unconditional jump to a destination().
/** * LIR operation that is an unconditional jump to a {@link #destination()}. */
public static class JumpOp extends LIRInstruction implements BlockEndOp { public static final LIRInstructionClass<JumpOp> TYPE = LIRInstructionClass.create(JumpOp.class); public static final EnumSet<OperandFlag> outgoingFlags = EnumSet.of(REG, STACK, CONST, OUTGOING); @Alive({REG, STACK, CONST, OUTGOING}) private Value[] outgoingValues; private final LabelRef destination; public JumpOp(LabelRef destination) { this(TYPE, destination); } protected JumpOp(LIRInstructionClass<? extends JumpOp> c, LabelRef destination) { super(c); this.destination = destination; this.outgoingValues = Value.NO_VALUES; } @Override public void emitCode(CompilationResultBuilder crb) { if (!crb.isSuccessorEdge(destination)) { crb.asm.jmp(destination.label()); } } public LabelRef destination() { return destination; } public void setPhiValues(Value[] values) { assert this.outgoingValues.length == 0; assert values != null; this.outgoingValues = values; } public int getPhiSize() { return outgoingValues.length; } public Value getOutgoingValue(int idx) { assert checkRange(idx); return outgoingValues[idx]; } public void clearOutgoingValues() { outgoingValues = Value.NO_VALUES; } private boolean checkRange(int idx) { return idx < outgoingValues.length; } }
Marker interface for a LIR operation that is a conditional jump.
/** * Marker interface for a LIR operation that is a conditional jump. */
public interface BranchOp extends BlockEndOp { }
Marker interface for a LIR operation that moves a value to getResult().
/** * Marker interface for a LIR operation that moves a value to {@link #getResult()}. */
public interface MoveOp { AllocatableValue getResult(); // Checkstyle: stop static MoveOp asMoveOp(LIRInstruction op) { return (MoveOp) op; } // Checkstyle: resume static boolean isMoveOp(LIRInstruction op) { return op.isMoveOp(); } }
Marker interface for a LIR operation that moves some non-constant value to another location.
/** * Marker interface for a LIR operation that moves some non-constant value to another location. */
public interface ValueMoveOp extends MoveOp { AllocatableValue getInput(); // Checkstyle: stop static ValueMoveOp asValueMoveOp(LIRInstruction op) { return (ValueMoveOp) op; } // Checkstyle: resume static boolean isValueMoveOp(LIRInstruction op) { return op.isValueMoveOp(); } }
Marker interface for a LIR operation that loads a getConstant().
/** * Marker interface for a LIR operation that loads a {@link #getConstant()}. */
public interface LoadConstantOp extends MoveOp { Constant getConstant(); // Checkstyle: stop static LoadConstantOp asLoadConstantOp(LIRInstruction op) { return (LoadConstantOp) op; } // Checkstyle: resume static boolean isLoadConstantOp(LIRInstruction op) { return op.isLoadConstantOp(); } }
An operation that saves registers to the stack. The set of saved registers can be pruned and a mapping from registers to the frame slots in which they are saved can be retrieved.
/** * An operation that saves registers to the stack. The set of saved registers can be * {@linkplain #remove(EconomicSet) pruned} and a mapping from registers to the frame slots in * which they are saved can be {@linkplain #getMap(FrameMap) retrieved}. */
public abstract static class SaveRegistersOp extends LIRInstruction { public static final LIRInstructionClass<SaveRegistersOp> TYPE = LIRInstructionClass.create(SaveRegistersOp.class);
The registers (potentially) saved by this operation.
/** * The registers (potentially) saved by this operation. */
protected final Register[] savedRegisters;
The slots to which the registers are saved.
/** * The slots to which the registers are saved. */
@Def(STACK) protected final AllocatableValue[] slots;
Params:
  • savedRegisters – the registers saved by this operation which may be subject to pruning
  • savedRegisterLocations – the slots to which the registers are saved
/** * * @param savedRegisters the registers saved by this operation which may be subject to * {@linkplain #remove(EconomicSet) pruning} * @param savedRegisterLocations the slots to which the registers are saved */
protected SaveRegistersOp(LIRInstructionClass<? extends SaveRegistersOp> c, Register[] savedRegisters, AllocatableValue[] savedRegisterLocations) { super(c); assert Arrays.asList(savedRegisterLocations).stream().allMatch(LIRValueUtil::isVirtualStackSlot); this.savedRegisters = savedRegisters; this.slots = savedRegisterLocations; }
Prunes doNotSave from the registers saved by this operation.
Params:
  • doNotSave – registers that should not be saved by this operation
Returns:the number of registers pruned
/** * Prunes {@code doNotSave} from the registers saved by this operation. * * @param doNotSave registers that should not be saved by this operation * @return the number of registers pruned */
public int remove(EconomicSet<Register> doNotSave) { return prune(doNotSave, savedRegisters); }
Gets a map from the saved registers saved by this operation to the frame slots in which they are saved.
Params:
  • frameMap – used to convert a virtual slot to a frame slot index
/** * Gets a map from the saved registers saved by this operation to the frame slots in which * they are saved. * * @param frameMap used to {@linkplain FrameMap#offsetForStackSlot(StackSlot) convert} a * virtual slot to a frame slot index */
public RegisterSaveLayout getMap(FrameMap frameMap) { int total = 0; for (int i = 0; i < savedRegisters.length; i++) { if (savedRegisters[i] != null) { total++; } } Register[] keys = new Register[total]; int[] values = new int[total]; if (total != 0) { int mapIndex = 0; for (int i = 0; i < savedRegisters.length; i++) { if (savedRegisters[i] != null) { keys[mapIndex] = savedRegisters[i]; assert isStackSlot(slots[i]) : "not a StackSlot: " + slots[i]; StackSlot slot = asStackSlot(slots[i]); values[mapIndex] = indexForStackSlot(frameMap, slot); mapIndex++; } } assert mapIndex == total; } return new RegisterSaveLayout(keys, values); } public Register[] getSavedRegisters() { return savedRegisters; } public EconomicSet<Register> getSaveableRegisters() { EconomicSet<Register> registers = EconomicSet.create(Equivalence.IDENTITY); for (Register r : savedRegisters) { registers.add(r); } return registers; } public AllocatableValue[] getSlots() { return slots; } @Override public abstract void emitCode(CompilationResultBuilder crb); static int prune(EconomicSet<Register> toRemove, Register[] registers) { int pruned = 0; for (int i = 0; i < registers.length; i++) { if (registers[i] != null) { if (toRemove.contains(registers[i])) { registers[i] = null; pruned++; } } } return pruned; }
Computes the index of a stack slot relative to slot 0. This is also the bit index of stack slots in the reference map.
Params:
  • slot – a stack slot
Returns:the index of the stack slot
/** * Computes the index of a stack slot relative to slot 0. This is also the bit index of * stack slots in the reference map. * * @param slot a stack slot * @return the index of the stack slot */
private static int indexForStackSlot(FrameMap frameMap, StackSlot slot) { assert frameMap.offsetForStackSlot(slot) % frameMap.getTarget().wordSize == 0; int value = frameMap.offsetForStackSlot(slot) / frameMap.getTarget().wordSize; return value; } }
Marker interface for an operation that restores the registers saved by SaveRegistersOp.
/** * Marker interface for an operation that restores the registers saved by * {@link SaveRegistersOp}. */
public interface RestoreRegistersOp { }
Marker interface for an operation that kills some set register and stack locations.
/** * Marker interface for an operation that kills some set register and stack locations. */
public interface ZapRegistersOp { }
A LIR operation that does nothing. If the operation records its position, it can be subsequently replaced.
/** * A LIR operation that does nothing. If the operation records its position, it can be * subsequently {@linkplain #replace(LIR, LIRInstruction) replaced}. */
public static final class NoOp extends LIRInstruction { public static final LIRInstructionClass<NoOp> TYPE = LIRInstructionClass.create(NoOp.class);
The block in which this instruction is located.
/** * The block in which this instruction is located. */
final AbstractBlockBase<?> block;
The block index of this instruction.
/** * The block index of this instruction. */
final int index; public NoOp(AbstractBlockBase<?> block, int index) { super(TYPE); this.block = block; this.index = index; } public void replace(LIR lir, LIRInstruction replacement) { ArrayList<LIRInstruction> instructions = lir.getLIRforBlock(block); assert instructions.get(index).equals(this) : String.format("Replacing the wrong instruction: %s instead of %s", instructions.get(index), this); instructions.set(index, replacement); } public void remove(LIR lir) { ArrayList<LIRInstruction> instructions = lir.getLIRforBlock(block); assert instructions.get(index).equals(this) : String.format("Removing the wrong instruction: %s instead of %s", instructions.get(index), this); instructions.remove(index); } @Override public void emitCode(CompilationResultBuilder crb) { if (block != null) { throw new GraalError(this + " should have been replaced"); } } } @Opcode("BLACKHOLE") public static final class BlackholeOp extends LIRInstruction { public static final LIRInstructionClass<BlackholeOp> TYPE = LIRInstructionClass.create(BlackholeOp.class); @Use({REG, STACK, CONST}) private Value value; public BlackholeOp(Value value) { super(TYPE); this.value = value; } @Override public void emitCode(CompilationResultBuilder crb) { // do nothing, just keep value alive until at least here } } public static final class BindToRegisterOp extends LIRInstruction { public static final LIRInstructionClass<BindToRegisterOp> TYPE = LIRInstructionClass.create(BindToRegisterOp.class); @Use({REG}) private Value value; public BindToRegisterOp(Value value) { super(TYPE); this.value = value; } @Override public void emitCode(CompilationResultBuilder crb) { // do nothing, just keep value alive until at least here } } @Opcode("SPILLREGISTERS") public static final class SpillRegistersOp extends LIRInstruction { public static final LIRInstructionClass<SpillRegistersOp> TYPE = LIRInstructionClass.create(SpillRegistersOp.class); public SpillRegistersOp() { super(TYPE); } @Override public boolean destroysCallerSavedRegisters() { return true; } @Override public void emitCode(CompilationResultBuilder crb) { // do nothing, just keep value alive until at least here } } public static final class StackMove extends LIRInstruction implements ValueMoveOp { public static final LIRInstructionClass<StackMove> TYPE = LIRInstructionClass.create(StackMove.class); @Def({STACK, HINT}) protected AllocatableValue result; @Use({STACK}) protected AllocatableValue input; public StackMove(AllocatableValue result, AllocatableValue input) { super(TYPE); this.result = result; this.input = input; } @Override public void emitCode(CompilationResultBuilder crb) { throw new GraalError(this + " should have been removed"); } @Override public AllocatableValue getInput() { return input; } @Override public AllocatableValue getResult() { return result; } } }