mirror of
https://github.com/fadden/6502bench.git
synced 2024-08-20 11:28:58 +00:00
Added generation of the relocation dictionary and constant body for segments in Load files. Also, don't reject files with v1 segments (whose length is specified as a block count) just because the EOF isn't a multiple of 512 bytes. Some executables don't pad out the last block. Various tweaks to output formatting.
267 lines
10 KiB
C#
267 lines
10 KiB
C#
/*
|
|
* Copyright 2020 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.Generic;
|
|
using System.Diagnostics;
|
|
|
|
using CommonUtil;
|
|
|
|
namespace SourceGen.Tools.Omf {
|
|
/// <summary>
|
|
/// Apple IIgs OMF relocation entry. These are generated from OMF relocation records.
|
|
/// Note that SUPER records may generate multiple instances of these.
|
|
/// </summary>
|
|
public class OmfReloc {
|
|
/// <summary>
|
|
/// Number of bytes to be relocated.
|
|
/// </summary>
|
|
public int Width { get; private set; }
|
|
|
|
/// <summary>
|
|
/// Number of bits to shift the result before storing. Positive values shift left,
|
|
/// negative values shift right (unsigned).
|
|
/// </summary>
|
|
public int Shift { get; private set; }
|
|
|
|
/// <summary>
|
|
/// Offset within segment of bytes to rewrite.
|
|
/// </summary>
|
|
public int Offset { get; private set; }
|
|
|
|
/// <summary>
|
|
/// Relative offset of the thing being referenced. The segment's address in memory
|
|
/// is added to this to yield the final value.
|
|
/// </summary>
|
|
public int RelOffset { get; private set; }
|
|
|
|
/// <summary>
|
|
/// File number of target segment. Normally 1. Will be -1 for intra-segment relocs.
|
|
/// </summary>
|
|
public int FileNum { get; private set; }
|
|
|
|
/// <summary>
|
|
/// Segment number of target segment. Will be -1 for intra-segment relocs.
|
|
/// </summary>
|
|
public int SegNum { get; private set; }
|
|
|
|
/// <summary>
|
|
/// Set to the SUPER type, or -1 if this record was not from a SUPER.
|
|
/// </summary>
|
|
public int SuperType { get; private set; }
|
|
|
|
|
|
/// <summary>
|
|
/// Constructor for RELOC/cRELOC.
|
|
/// </summary>
|
|
/// <param name="width">Width in bytes of relocation.</param>
|
|
/// <param name="shift">Bit-shift amount.</param>
|
|
/// <param name="offset">Offset within segment of relocation.</param>
|
|
/// <param name="relOffset">Relative offset of relocation reference.</param>
|
|
/// <param name="fromSuper">True if generated from SUPER.</param>
|
|
private OmfReloc(int width, int shift, int offset, int relOffset, int superType) {
|
|
FileNum = SegNum = -1;
|
|
Width = width;
|
|
Shift = shift;
|
|
Offset = offset;
|
|
RelOffset = relOffset;
|
|
SuperType = superType;
|
|
}
|
|
|
|
/// <summary>
|
|
/// Constructor for INTERSEG/cINTERSEG.
|
|
/// </summary>
|
|
/// <param name="width">Width in bytes of relocation.</param>
|
|
/// <param name="shift">Bit-shift amount.</param>
|
|
/// <param name="offset">Offset within segment of relocation.</param>
|
|
/// <param name="relOffset">Relative offset of relocation reference.</param>
|
|
/// <param name="fileNum">File number.</param>
|
|
/// <param name="segNum">Segment number.</param>
|
|
/// <param name="fromSuper">True if generated from SUPER.</param>
|
|
private OmfReloc(int width, int shift, int offset, int relOffset, int fileNum,
|
|
int segNum, int superType) {
|
|
Width = width;
|
|
Shift = shift;
|
|
Offset = offset;
|
|
RelOffset = relOffset;
|
|
FileNum = fileNum;
|
|
SegNum = segNum;
|
|
SuperType = superType;
|
|
}
|
|
|
|
/// <summary>
|
|
/// Adds one or more OmfReloc instances to the list to represent the provided record.
|
|
/// </summary>
|
|
/// <param name="omfSeg">Segment that contains the record.</param>
|
|
/// <param name="omfRec">Record to add.</param>
|
|
/// <param name="data">File data.</param>
|
|
/// <param name="relocs">List of relocations. New entries will be appended.</param>
|
|
/// <returns>True on success.</returns>
|
|
public static bool GenerateRelocs(OmfSegment omfSeg, OmfRecord omfRec, byte[] data,
|
|
List<OmfReloc> relocs) {
|
|
try {
|
|
return DoGenerateRelocs(omfSeg, omfRec, data, relocs);
|
|
} catch (IndexOutOfRangeException ioore) {
|
|
Debug.WriteLine("Caught IOORE during reloc gen (" + omfRec.Op + "): " +
|
|
ioore.Message);
|
|
return false;
|
|
}
|
|
}
|
|
|
|
/// <summary>
|
|
/// Adds one or more OmfReloc instances to the list to represent the provided record.
|
|
/// </summary>
|
|
private static bool DoGenerateRelocs(OmfSegment omfSeg, OmfRecord omfRec, byte[] data,
|
|
List<OmfReloc> relocs) {
|
|
int offset = omfRec.FileOffset;
|
|
Debug.Assert(data[offset] == (int)omfRec.Op);
|
|
switch (omfRec.Op) {
|
|
case OmfRecord.Opcode.RELOC: {
|
|
byte width = data[offset + 1];
|
|
sbyte shift = (sbyte)data[offset + 2];
|
|
int off = RawData.GetWord(data, offset + 3, 4, false);
|
|
int relOff = RawData.GetWord(data, offset + 7, 4, false);
|
|
relocs.Add(new OmfReloc(width, shift, off, relOff, -1));
|
|
}
|
|
break;
|
|
case OmfRecord.Opcode.cRELOC: {
|
|
byte width = data[offset + 1];
|
|
sbyte shift = (sbyte)data[offset + 2];
|
|
int off = RawData.GetWord(data, offset + 3, 2, false);
|
|
int relOff = RawData.GetWord(data, offset + 5, 2, false);
|
|
relocs.Add(new OmfReloc(width, shift, off, relOff, -1));
|
|
}
|
|
break;
|
|
case OmfRecord.Opcode.INTERSEG: {
|
|
byte width = data[offset + 1];
|
|
sbyte shift = (sbyte)data[offset + 2];
|
|
int off = RawData.GetWord(data, offset + 3, 4, false);
|
|
int fileNum = RawData.GetWord(data, offset + 7, 2, false);
|
|
int segNum = RawData.GetWord(data, offset + 9, 2, false);
|
|
int relOff = RawData.GetWord(data, offset + 11, 4, false);
|
|
relocs.Add(new OmfReloc(width, shift, off, relOff, fileNum, segNum, -1));
|
|
}
|
|
break;
|
|
case OmfRecord.Opcode.cINTERSEG: {
|
|
byte width = data[offset + 1];
|
|
sbyte shift = (sbyte)data[offset + 2];
|
|
int off = RawData.GetWord(data, offset + 3, 2, false);
|
|
int fileNum = 1;
|
|
int segNum = data[offset + 5];
|
|
int relOff = RawData.GetWord(data, offset + 6, 2, false);
|
|
relocs.Add(new OmfReloc(width, shift, off, relOff, fileNum, segNum, -1));
|
|
}
|
|
break;
|
|
case OmfRecord.Opcode.SUPER:
|
|
if (!GenerateRelocForSuper(omfSeg, omfRec, data, relocs)) {
|
|
return false;
|
|
}
|
|
break;
|
|
default:
|
|
Debug.Assert(false);
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
|
|
/// <summary>
|
|
/// Generates a series of relocation items for a SUPER record.
|
|
/// </summary>
|
|
private static bool GenerateRelocForSuper(OmfSegment omfSeg, OmfRecord omfRec, byte[] data,
|
|
List<OmfReloc> relocs) {
|
|
int offset = omfRec.FileOffset;
|
|
int remaining = RawData.GetWord(data, offset + 1, 4, false);
|
|
int type = data[offset + 5];
|
|
offset += 6; // we've consumed 6 bytes
|
|
remaining--; // ...but only 1 counts against the SUPER length
|
|
|
|
int width, shift, fileNum, segNum;
|
|
bool needSegNum = false;
|
|
|
|
if (type == 0) {
|
|
// SUPER RELOC2
|
|
width = 2;
|
|
shift = 0;
|
|
fileNum = segNum = -1;
|
|
} else if (type == 1) {
|
|
// SUPER RELOC3
|
|
width = 3;
|
|
shift = 0;
|
|
fileNum = segNum = -1;
|
|
} else if (type >= 2 && type <= 13) {
|
|
// SUPER INTERSEG1 - SUPER INTERSEG12
|
|
width = 3;
|
|
shift = 0;
|
|
fileNum = type - 1;
|
|
segNum = -100;
|
|
needSegNum = true;
|
|
} else if (type >= 14 && type <= 25) {
|
|
// SUPER INTERSEG13 - SUPER INTERSEG24
|
|
width = 2;
|
|
shift = 0;
|
|
fileNum = 1;
|
|
segNum = type - 13;
|
|
} else if (type >= 26 && type <= 37) {
|
|
// SUPER INTERSEG25 - SUPER INTERSEG36
|
|
width = 2;
|
|
shift = -16; // right shift
|
|
fileNum = 1;
|
|
segNum = type - 25;
|
|
} else {
|
|
return false;
|
|
}
|
|
|
|
int page = 0;
|
|
while (remaining > 0) {
|
|
int patchCount = data[offset++];
|
|
remaining--;
|
|
|
|
if ((patchCount & 0x80) != 0) {
|
|
// high bit set, this is a skip-count
|
|
page += (patchCount & 0x7f);
|
|
continue;
|
|
}
|
|
patchCount++; // zero means one patch
|
|
while (patchCount-- != 0) {
|
|
int patchOff = data[offset++];
|
|
remaining--;
|
|
|
|
int relocOff = page * 256 + patchOff;
|
|
|
|
byte[] constData = omfSeg.GetConstData();
|
|
int relocRelOff = RawData.GetWord(constData, relocOff, 2, false);
|
|
if (needSegNum) {
|
|
segNum = constData[relocOff + 2];
|
|
}
|
|
|
|
relocs.Add(new OmfReloc(width, shift, relocOff, relocRelOff,
|
|
fileNum, segNum, type));
|
|
}
|
|
|
|
page++;
|
|
}
|
|
|
|
if (remaining < 0) {
|
|
Debug.WriteLine("Ran off end of SUPER record");
|
|
Debug.Assert(false);
|
|
return false;
|
|
}
|
|
|
|
return true;
|
|
}
|
|
}
|
|
}
|