jdk/src/java.base/share/classes/java/lang/classfile/instruction/LoadInstruction.java
2024-10-02 03:30:02 +00:00

87 lines
3.5 KiB
Java

/*
* Copyright (c) 2022, Oracle and/or its affiliates. All rights reserved.
* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
*
* This code is free software; you can redistribute it and/or modify it
* under the terms of the GNU General Public License version 2 only, as
* published by the Free Software Foundation. Oracle designates this
* particular file as subject to the "Classpath" exception as provided
* by Oracle in the LICENSE file that accompanied this code.
*
* This code is distributed in the hope that it will be useful, but WITHOUT
* ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
* FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
* version 2 for more details (a copy is included in the LICENSE file that
* accompanied this code).
*
* You should have received a copy of the GNU General Public License version
* 2 along with this work; if not, write to the Free Software Foundation,
* Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
*
* Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
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package java.lang.classfile.instruction;
import java.lang.classfile.CodeElement;
import java.lang.classfile.CodeModel;
import java.lang.classfile.Instruction;
import java.lang.classfile.Opcode;
import java.lang.classfile.TypeKind;
import jdk.internal.classfile.impl.AbstractInstruction;
import jdk.internal.classfile.impl.BytecodeHelpers;
import jdk.internal.classfile.impl.Util;
import jdk.internal.javac.PreviewFeature;
/**
* Models a local variable load instruction in the {@code code} array of a
* {@code Code} attribute. Corresponding opcodes will have a {@code kind} of
* {@link Opcode.Kind#LOAD}. Delivered as a {@link CodeElement} when
* traversing the elements of a {@link CodeModel}.
*
* @since 22
*/
@PreviewFeature(feature = PreviewFeature.Feature.CLASSFILE_API)
public sealed interface LoadInstruction extends Instruction
permits AbstractInstruction.BoundLoadInstruction,
AbstractInstruction.UnboundLoadInstruction {
/**
* {@return the local variable slot to load from}
*/
int slot();
/**
* {@return the type of the value to be loaded}
*/
TypeKind typeKind();
/**
* {@return a local variable load instruction}
*
* @param kind the type of the value to be loaded
* @param slot the local variable slot to load from
* @throws IllegalArgumentException if {@code kind} is
* {@link TypeKind#VOID void} or {@code slot} is out of range
*/
static LoadInstruction of(TypeKind kind, int slot) {
var opcode = BytecodeHelpers.loadOpcode(kind, slot); // validates slot, trusted
return new AbstractInstruction.UnboundLoadInstruction(opcode, slot);
}
/**
* {@return a local variable load instruction}
*
* @param op the opcode for the specific type of load instruction,
* which must be of kind {@link Opcode.Kind#LOAD}
* @param slot the local variable slot to load from
* @throws IllegalArgumentException if the opcode kind is not
* {@link Opcode.Kind#LOAD} or {@code slot} is out of range
*/
static LoadInstruction of(Opcode op, int slot) {
Util.checkKind(op, Opcode.Kind.LOAD);
BytecodeHelpers.validateSlot(op, slot, true);
return new AbstractInstruction.UnboundLoadInstruction(op, slot);
}
}