/*
* Copyright 2018 faddenSoft
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
using System;
using System.Collections;
using System.Collections.Generic;
using System.Diagnostics;
namespace SourceGen {
///
/// Tracks a set of offsets that reference a single address or label.
///
/// This is used internally, when refactoring labels, as well as for the "references"
/// UI panel and label localizer.
///
public class XrefSet : IEnumerable {
///
/// Reference type. This is mostly useful for display to the user.
///
public enum XrefType {
Unknown = 0,
SubCallOp, // subroutine call
BranchOp, // branch instruction
RefFromData, // reference in data area, e.g. ".dd2 "
MemAccessOp, // instruction that accesses memory, or refers to an address
}
///
/// Cross-reference descriptor. Instances are immutable.
///
public class Xref {
///
/// Offset of start of instruction or data that refers to the target offset.
///
public int Offset { get; private set; }
///
/// True if this reference is by name.
///
public bool IsSymbolic { get; private set; }
///
/// Type of reference.
///
public XrefType Type { get; private set; }
///
/// For Type==MemAccessOp, what type of memory access is performed.
///
public Asm65.OpDef.MemoryEffect AccType { get; private set; }
///
/// Adjustment to symbol. For example, "LDA label+2" adds an xref entry to
/// "label", with an adjustment of +2.
///
public int Adjustment { get; private set; }
public Xref(int offset, bool isSymbolic, XrefType type,
Asm65.OpDef.MemoryEffect accType, int adjustment) {
Offset = offset;
IsSymbolic = isSymbolic;
Type = type;
AccType = accType;
Adjustment = adjustment;
}
public override string ToString() {
return "Xref off=+" + Offset.ToString("x6") + " sym=" + IsSymbolic +
" type=" + Type + " accType= " + AccType + " adj=" + Adjustment;
}
}
///
/// Internal storage for xrefs.
///
private List mRefs = new List();
///
/// Constructs an empty set.
///
public XrefSet() { }
///
/// Returns the number of cross-references in the set.
///
public int Count { get { return mRefs.Count; } }
///
/// Removes all entries from the set.
///
public void Clear() {
mRefs.Clear();
}
///
/// Returns the Nth entry in the set.
///
public Xref this[int index] {
get {
return mRefs[index];
}
}
///
/// Adds an xref to the set.
///
public void Add(Xref xref) {
// TODO(someday): not currently enforcing set behavior; start by adding .equals to
// Xref, then check Contains before allowing Add. (Should probably complain
// loudly if item already exists, since we're not expecting that.)
mRefs.Add(xref);
}
// IEnumerable
public IEnumerator GetEnumerator() {
return ((IEnumerable)mRefs).GetEnumerator();
}
// IEnumerable, generic
IEnumerator IEnumerable.GetEnumerator() {
return ((IEnumerable)mRefs).GetEnumerator();
}
}
}