mirror of
https://github.com/fadden/6502bench.git
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51081c5db0
The code that found a nearby data target for an instruction operand was searching backward but not forward. We now take one step forward, so that "LDA TABLE-1,Y" fills in automatically. This altered 2008-address-changes, which had just this situation. It didn't alter 2010-target-adjustment, but the existing tests were insufficient and have been improved.
1316 lines
62 KiB
C#
1316 lines
62 KiB
C#
/*
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* Copyright 2019 faddenSoft
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*
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* Licensed under the Apache License, Version 2.0 (the "License");
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* you may not use this file except in compliance with the License.
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* You may obtain a copy of the License at
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*
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* http://www.apache.org/licenses/LICENSE-2.0
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*
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* Unless required by applicable law or agreed to in writing, software
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* distributed under the License is distributed on an "AS IS" BASIS,
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* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
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* See the License for the specific language governing permissions and
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* limitations under the License.
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*/
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using System;
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using System.Diagnostics;
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using Asm65;
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using CommonUtil;
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using TextScanMode = SourceGen.ProjectProperties.AnalysisParameters.TextScanMode;
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namespace SourceGen {
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/// <summary>
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/// Auto-detection of structured data.
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///
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/// This class doesn't really hold any state. It's just a convenient place to collect
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/// the items needed by the analyzer methods.
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/// </summary>
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public class DataAnalysis {
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// Minimum number of consecutive identical bytes for something to be called a "run".
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private const int MIN_RUN_LENGTH = 5;
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// Minimum length for treating data as a run if the byte is a printable character.
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// (Alternatively, the maximum length of a character string composed of a single value.)
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// Anything shorter than this is handled with a string directive, anything this long or
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// longer becomes FILL. This should be larger than the MinCharsForString parameter.
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private const int MAX_STRING_RUN_LENGTH = 62;
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// Absolute minimum string length for auto-detection. This is used when generating the
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// data tables.
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public const int MIN_STRING_LENGTH = 3;
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// Minimum length for an ASCII string. Anything shorter is just output as bytes.
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// This is the default value; the actual value is configured as a project preference.
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public const int DEFAULT_MIN_STRING_LENGTH = 4;
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// Set min chars to this to disable string detection.
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public const int MIN_CHARS_FOR_STRING_DISABLED = int.MaxValue;
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/// <summary>
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/// Project with which we are associated.
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/// </summary>
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private DisasmProject mProject;
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/// <summary>
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/// Reference to 65xx data.
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/// </summary>
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private byte[] mFileData;
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/// <summary>
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/// Attributes, one per byte in input file.
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/// </summary>
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private Anattrib[] mAnattribs;
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/// <summary>
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/// Configurable parameters.
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/// </summary>
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private ProjectProperties.AnalysisParameters mAnalysisParams;
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/// <summary>
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/// Debug trace log.
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/// </summary>
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private DebugLog mDebugLog = new DebugLog(DebugLog.Priority.Silent);
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public DebugLog DebugLog {
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set {
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mDebugLog = value;
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}
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}
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public DataAnalysis(DisasmProject proj, Anattrib[] anattribs) {
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mProject = proj;
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mAnattribs = anattribs;
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mFileData = proj.FileData;
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mAnalysisParams = proj.ProjectProps.AnalysisParams;
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}
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// Internal log functions. If we're concerned about performance overhead due to
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// call-site string concatenation, we can #ifdef these to nothing in release builds,
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// which should allow the compiler to elide the concat.
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#if false
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private void LogV(int offset, string msg) {
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if (mDebugLog.IsLoggable(DebugLog.Priority.Verbose)) {
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mDebugLog.LogV("+" + offset.ToString("x6") + " " + msg);
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}
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}
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#else
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private void LogV(int offset, string msg) { }
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#endif
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private void LogD(int offset, string msg) {
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if (mDebugLog.IsLoggable(DebugLog.Priority.Debug)) {
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mDebugLog.LogD("+" + offset.ToString("x6") + " " + msg);
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}
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}
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private void LogI(int offset, string msg) {
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if (mDebugLog.IsLoggable(DebugLog.Priority.Info)) {
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mDebugLog.LogI("+" + offset.ToString("x6") + " " + msg);
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}
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}
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private void LogW(int offset, string msg) {
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if (mDebugLog.IsLoggable(DebugLog.Priority.Warning)) {
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mDebugLog.LogW("+" + offset.ToString("x6") + " " + msg);
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}
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}
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private void LogE(int offset, string msg) {
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if (mDebugLog.IsLoggable(DebugLog.Priority.Error)) {
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mDebugLog.LogE("+" + offset.ToString("x6") + " " + msg);
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}
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}
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/// <summary>
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/// Analyzes instruction operands and Address data descriptors to identify references
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/// to offsets within the file.
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///
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/// Instructions with format descriptors are left alone. Instructions with
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/// operand offsets but no descriptor will have a descriptor generated
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/// using the label at the target offset; if the target offset is unlabeled,
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/// a unique label will be generated. Data descriptors with type=Address are
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/// handled the same way.
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///
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/// In some cases, such as a reference to the middle of an instruction, we will
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/// label a nearby location instead.
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///
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/// This should be called after code analysis has run, user labels and format
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/// descriptors have been applied, and platform/project symbols have been merged
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/// into the symbol table.
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/// </summary>
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/// <returns>True on success.</returns>
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public void AnalyzeDataTargets() {
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mDebugLog.LogI("Analyzing data targets...");
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for (int offset = 0; offset < mAnattribs.Length; offset++) {
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Anattrib attr = mAnattribs[offset];
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if (attr.IsInstructionStart) {
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if (attr.DataDescriptor != null) {
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// It's being shown as numeric, or as a reference to some other symbol.
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// Either way there's nothing further for us to do. (Technically we
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// would want to treat it like the no-descriptor case if the type was
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// numeric/Address, but we don't allow that for instructions.)
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//
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// Project and platform symbols are applied later.
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Debug.Assert(attr.DataDescriptor.FormatSubType !=
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FormatDescriptor.SubType.Address);
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continue;
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}
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int operandOffset = attr.OperandOffset;
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if (operandOffset >= 0) {
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// This is an offset reference: a branch or data access instruction whose
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// target is inside the file. Create a FormatDescriptor for it, and
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// generate a label at the target if one is not already present.
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SetDataTarget(offset, attr.Length, operandOffset);
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}
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// We advance by a single byte, rather than .Length, in case there's
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// an instruction embedded inside another one.
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} else if (attr.DataDescriptor != null) {
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// We can't check IsDataStart / IsInlineDataStart because the bytes might
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// still be uncategorized. If there's a user-specified format, check it
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// to see if it's an address.
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FormatDescriptor dfd = attr.DataDescriptor;
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// Is this numeric/Address?
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if ((dfd.FormatType == FormatDescriptor.Type.NumericLE ||
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dfd.FormatType == FormatDescriptor.Type.NumericBE) &&
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dfd.FormatSubType == FormatDescriptor.SubType.Address) {
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// Treat like an absolute address. Convert the operand
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// to an address, then resolve the file offset.
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int address = RawData.GetWord(mFileData, offset, dfd.Length,
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(dfd.FormatType == FormatDescriptor.Type.NumericBE));
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if (dfd.Length < 3) {
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// Bank not specified by data, add current program bank. Not always
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// correct, but should be often enough. In most cases we'd just
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// assume a correct data bank register, but here we need to find
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// a file offset, so we have to assume data bank == program bank
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// (unless we find a good way to track the data bank register).
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address |= attr.Address & 0x7fff0000;
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}
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int operandOffset = mProject.AddrMap.AddressToOffset(offset, address);
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if (operandOffset >= 0) {
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SetDataTarget(offset, dfd.Length, operandOffset);
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}
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}
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// For other formats, we don't need to do anything. Numeric/Address is
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// the only one that represents an offset reference. Numeric/Symbol
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// is a name reference. The others are just data.
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// There shouldn't be any data items inside other data items, so we
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// can just skip forward.
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offset += mAnattribs[offset].DataDescriptor.Length - 1;
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}
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}
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}
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/// <summary>
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/// Extracts the operand offset from a data item. Only useful for numeric/Address
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/// and numeric/Symbol.
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/// </summary>
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/// <param name="proj">Project reference.</param>
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/// <param name="offset">Offset of data item.</param>
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/// <returns>Operand offset, or -1 if not applicable.</returns>
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public static int GetDataOperandOffset(DisasmProject proj, int offset) {
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Anattrib attr = proj.GetAnattrib(offset);
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if (!attr.IsDataStart && !attr.IsInlineDataStart) {
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return -1;
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}
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FormatDescriptor dfd = attr.DataDescriptor;
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// Is this numeric/Address or numeric/Symbol?
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if ((dfd.FormatType != FormatDescriptor.Type.NumericLE &&
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dfd.FormatType != FormatDescriptor.Type.NumericBE) ||
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(dfd.FormatSubType != FormatDescriptor.SubType.Address &&
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dfd.FormatSubType != FormatDescriptor.SubType.Symbol)) {
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return -1;
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}
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// Treat like an absolute address. Convert the operand
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// to an address, then resolve the file offset.
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int address = RawData.GetWord(proj.FileData, offset, dfd.Length,
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(dfd.FormatType == FormatDescriptor.Type.NumericBE));
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if (dfd.Length < 3) {
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// Add the program bank where the data bank should go. Not perfect but
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// we don't have anything better at the moment.
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address |= attr.Address & 0x7fff0000;
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}
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int operandOffset = proj.AddrMap.AddressToOffset(offset, address);
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return operandOffset;
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}
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/// <summary>
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/// Returns the "base" operand offset. If the byte at the specified offset is not the
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/// start of a code/data/inline-data item, walk backward until the start is found.
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/// </summary>
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/// <param name="proj">Project reference.</param>
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/// <param name="offset">Start offset.</param>
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/// <returns>Base offset.</returns>
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public static int GetBaseOperandOffset(DisasmProject proj, int offset) {
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Debug.Assert(offset >= 0 && offset < proj.FileDataLength);
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while (!proj.GetAnattrib(offset).IsStart) {
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offset--;
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// Should not be possible to walk off the top of the list, since we're in
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// the middle of something.
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Debug.Assert(offset >= 0);
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}
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return offset;
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}
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/// <summary>
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/// Creates a FormatDescriptor in the Anattrib array at srcOffset that links to
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/// targetOffset, or a nearby label. If targetOffset doesn't have a useful label,
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/// one will be generated.
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///
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/// This is used for both instruction and data operands.
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/// </summary>
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/// <param name="srcOffset">Offset of instruction or address data.</param>
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/// <param name="srcLen">Length of instruction or data item.</param>
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/// <param name="targetOffset">Offset of target.</param>
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private void SetDataTarget(int srcOffset, int srcLen, int targetOffset) {
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// NOTE: don't try to cache mAnattribs[targetOffset] -- we may be changing
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// targetOffset and/or altering the Anattrib entry, so grabbing a copy of the
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// struct may lead to problems.
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// If the target offset has a symbol assigned, use it. Otherwise, try to
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// find something nearby that might be more appropriate.
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int origTargetOffset = targetOffset;
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if (mAnattribs[targetOffset].Symbol == null) {
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if (mAnalysisParams.SeekNearbyTargets) {
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targetOffset = FindAlternateTarget(srcOffset, targetOffset);
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}
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// If we're not interested in seeking nearby targets, or we are but we failed
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// to find something useful, we need to make sure that we're not pointing
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// into the middle of the instruction. The assembler will only see labels on
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// the opcode bytes, so if we're pointing at the middle we need to back up.
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if (mAnattribs[targetOffset].IsInstruction &&
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!mAnattribs[targetOffset].IsInstructionStart) {
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while (!mAnattribs[--targetOffset].IsInstructionStart) {
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// Should not be possible to move past the start of the file,
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// since we know we're in the middle of an instruction.
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Debug.Assert(targetOffset > 0);
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}
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} else if (!mAnattribs[targetOffset].IsInstruction &&
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!mAnattribs[targetOffset].IsStart) {
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// This is not part of an instruction, and is not the start of a formatted
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// data area. However, it might be part of a formatted data area, in which
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// case we need to avoid creating an auto label in the middle. So we seek
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// backward, looking for the first offset with a descriptor. If that
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// descriptor includes this offset, we set the target offset to that.
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// (Note the uncategorized data pass hasn't run yet, so only instructions
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// and offsets identified by users or scripts have been categorized.)
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//
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// ?? Can we use GetBaseOperandOffset(), which searches for IsStart?
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int scanOffset = targetOffset;
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while (--scanOffset >= 0) {
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FormatDescriptor dfd = mAnattribs[scanOffset].DataDescriptor;
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if (dfd != null) {
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if (scanOffset + dfd.Length > targetOffset) {
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// Found a descriptor that encompasses target offset. Adjust
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// target to point at the start of the region.
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targetOffset = scanOffset;
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}
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// Descriptors aren't allowed to overlap, so either way we're done.
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break;
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}
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}
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}
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}
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if (mAnattribs[targetOffset].Symbol == null) {
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// No label at target offset, generate one.
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//
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// Generally speaking, the label we generate will be unique, because it
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// incorporates the address. It's possible through various means to end
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// up with a user or platform label that matches an auto label, so we
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// need to do some renaming in that case. Shouldn't happen often.
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Symbol sym = AutoLabel.GenerateUniqueForAddress(mAnattribs[targetOffset].Address,
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mProject.SymbolTable, "L");
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mAnattribs[targetOffset].Symbol = sym;
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// This will throw if the symbol already exists. That is the desired
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// behavior, as that would be a bug.
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mProject.SymbolTable.Add(sym);
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}
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// Create a Numeric/Symbol descriptor that references the target label. If the
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// source offset already had a descriptor (e.g. Numeric/Address data item),
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// this will replace it in the Anattrib array. (The user-specified format
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// is unaffected.)
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//
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// Doing this by target symbol, rather than offset in a Numeric/Address item,
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// allows us to avoid carrying the adjustment stuff everywhere. OTOH we have
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// to manually refactor label renames in the display list if we don't want to
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// redo the data analysis.
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bool isBigEndian = false;
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if (mAnattribs[srcOffset].DataDescriptor != null) {
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LogD(srcOffset, "Replacing " + mAnattribs[srcOffset].DataDescriptor +
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" with reference to " + mAnattribs[targetOffset].Symbol.Label +
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", adj=" + (origTargetOffset - targetOffset));
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if (mAnattribs[srcOffset].DataDescriptor.FormatType ==
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FormatDescriptor.Type.NumericBE) {
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isBigEndian = true;
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}
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} else {
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LogV(srcOffset, "Creating weak reference to label " +
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mAnattribs[targetOffset].Symbol.Label +
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", adj=" + (origTargetOffset - targetOffset));
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}
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mAnattribs[srcOffset].DataDescriptor = FormatDescriptor.Create(srcLen,
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new WeakSymbolRef(mAnattribs[targetOffset].Symbol.Label, WeakSymbolRef.Part.Low),
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isBigEndian);
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}
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/// <summary>
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/// Given a reference from srcOffset to targetOffset, check to see if there's a
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/// nearby location that we'd prefer to refer to. For example, if targetOffset points
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/// into the middle of an instruction, we'd rather have it refer to the first byte.
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/// </summary>
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/// <param name="srcOffset">Reference source.</param>
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/// <param name="targetOffset">Reference target.</param>
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/// <returns>New value for targetOffset, or original value if nothing better was
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/// found.</returns>
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private int FindAlternateTarget(int srcOffset, int targetOffset) {
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int origTargetOffset = targetOffset;
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// Is the target outside the instruction stream? If it's just referencing data,
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// do a simple check and move on.
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if (!mAnattribs[targetOffset].IsInstruction) {
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// We want to use user-defined labels whenever possible. If they're accessing
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// memory within a few bytes, use that. We don't want to do this for
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// code references, though, or our branches will get all weird.
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//
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// We look a few back and one forward. Stuff backward (which turns into
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// LABEL+N) has priority over forward (which becomes LABEL-N).
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//
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// TODO(someday): make parameters user-configurable?
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const int MAX_FWD = 1;
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const int MAX_BACK = 3;
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int probeOffset = targetOffset;
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bool back = true;
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while (true) {
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if (back) {
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// moving backward
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probeOffset--;
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if (probeOffset < 0 || probeOffset < targetOffset - MAX_BACK) {
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// too far back, reverse direction
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probeOffset = targetOffset;
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back = false;
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}
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}
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if (!back) {
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// moving forward
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probeOffset++;
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if (probeOffset >= mAnattribs.Length ||
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probeOffset > targetOffset + MAX_FWD) {
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break; // done
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}
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}
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Symbol sym = mAnattribs[probeOffset].Symbol;
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if (sym != null && sym.SymbolSource == Symbol.Source.User) {
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// Found a nearby user label. Make sure it's actually nearby.
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int addrDiff = mAnattribs[targetOffset].Address -
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mAnattribs[probeOffset].Address;
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if (addrDiff == targetOffset - probeOffset) {
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targetOffset = probeOffset;
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break;
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} else {
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Debug.WriteLine("NOT probing past address boundary change (src=+" +
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srcOffset.ToString("x6") +
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" targ=+" + targetOffset.ToString("x6") +
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" probe=+" + probeOffset.ToString("x6") + ")");
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// No point in continuing to search this direction, but we might
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// need to look the other way.
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if (back) {
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probeOffset = targetOffset;
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back = false;
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} else {
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break;
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}
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}
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}
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}
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return targetOffset;
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}
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// Target is an instruction. Is the source an instruction or data element
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// (e.g. ".dd2 <addr>").
|
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if (!mAnattribs[srcOffset].IsInstructionStart) {
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// Might be address-1 to set up an RTS. If the target address isn't
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// an instruction start, check to see if the following byte is.
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if (!mAnattribs[targetOffset].IsInstructionStart &&
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targetOffset + 1 < mAnattribs.Length &&
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mAnattribs[targetOffset + 1].IsInstructionStart) {
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LogD(srcOffset, "Offsetting address reference");
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targetOffset++;
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}
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return targetOffset;
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}
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// Source is an instruction, so we have an instruction referencing an instruction.
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// Could be a branch, an address push, or self-modifying code.
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OpDef op = mProject.CpuDef.GetOpDef(mProject.FileData[srcOffset]);
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if (op.IsBranchOrSubCall) {
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// Don't mess with jumps and branches -- always go directly to the
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// target address.
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} else if (op == OpDef.OpPEA_StackAbs || op == OpDef.OpPER_StackPCRelLong) {
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// They might be pushing address-1 to set up an RTS. If the target address isn't
|
|
// an instruction start, check to see if the following byte is.
|
|
if (!mAnattribs[targetOffset].IsInstructionStart &&
|
|
targetOffset + 1 < mAnattribs.Length &&
|
|
mAnattribs[targetOffset + 1].IsInstructionStart) {
|
|
LogD(srcOffset, "Offsetting PEA/PER");
|
|
targetOffset++;
|
|
}
|
|
} else {
|
|
// Data operation (LDA, STA, etc). This could be self-modifying code, or
|
|
// an indexed access with an offset base address (LDA addr-1,Y) to an
|
|
// adjacent data area. Check to see if there's data right after this.
|
|
bool nearbyData = false;
|
|
for (int i = targetOffset + 1; i <= targetOffset + 2; i++) {
|
|
if (i < mAnattribs.Length && !mAnattribs[i].IsInstruction) {
|
|
targetOffset = i;
|
|
nearbyData = true;
|
|
break;
|
|
}
|
|
}
|
|
if (!nearbyData && !mAnattribs[targetOffset].IsInstructionStart) {
|
|
// There's no data nearby, and the target is not the start of the
|
|
// instruction, so this is probably self-modifying code. We want
|
|
// the label to be on the opcode, so back up to the instruction start.
|
|
while (!mAnattribs[--targetOffset].IsInstructionStart) {
|
|
// Should not be possible to move past the start of the file,
|
|
// since we know we're in the middle of an instruction.
|
|
Debug.Assert(targetOffset > 0);
|
|
}
|
|
}
|
|
}
|
|
|
|
if (targetOffset != origTargetOffset) {
|
|
LogV(srcOffset, "Creating instruction ref adj=" +
|
|
(origTargetOffset - targetOffset));
|
|
}
|
|
|
|
return targetOffset;
|
|
}
|
|
|
|
/// <summary>
|
|
/// Analyzes uncategorized regions of the file to see if they fit common patterns.
|
|
///
|
|
/// This is re-run after most changes to the project, so we don't want to do anything
|
|
/// crazily expensive.
|
|
/// </summary>
|
|
/// <returns>True on success.</returns>
|
|
public void AnalyzeUncategorized() {
|
|
FormatDescriptor oneByteDefault = FormatDescriptor.Create(1,
|
|
FormatDescriptor.Type.Default, FormatDescriptor.SubType.None);
|
|
FormatDescriptor.DebugPrefabBump(-1);
|
|
|
|
// If it hasn't been identified as code or data, set the "data" flag to
|
|
// give it a positive identification as data. (This should be the only
|
|
// place outside of CodeAnalysis that sets this flag.) This isn't strictly
|
|
// necessary, but it helps us assert things when pieces start moving around.
|
|
for (int offset = 0; offset < mAnattribs.Length; offset++) {
|
|
Anattrib attr = mAnattribs[offset];
|
|
if (attr.IsInlineData) {
|
|
// While we're here, add a default format descriptor for inline data
|
|
// that doesn't have one. We don't try to analyze it otherwise.
|
|
if (attr.DataDescriptor == null) {
|
|
mAnattribs[offset].DataDescriptor = oneByteDefault;
|
|
FormatDescriptor.DebugPrefabBump();
|
|
}
|
|
} else if (!attr.IsInstruction) {
|
|
mAnattribs[offset].IsData = true;
|
|
}
|
|
}
|
|
|
|
mDebugLog.LogI("Analyzing uncategorized data...");
|
|
|
|
int startOffset = -1;
|
|
for (int offset = 0; offset < mAnattribs.Length; ) {
|
|
// We want to find a contiguous series of offsets which are not known
|
|
// to hold code or data. We stop if we encounter a user-defined label
|
|
// or format descriptor.
|
|
Anattrib attr = mAnattribs[offset];
|
|
|
|
if (attr.IsInstruction || attr.IsInlineData || attr.IsDataStart) {
|
|
// Instruction, inline data, or formatted data known to be here. Analyze
|
|
// previous chunk, then advance past this.
|
|
if (startOffset >= 0) {
|
|
AnalyzeRange(startOffset, offset - 1);
|
|
startOffset = -1;
|
|
}
|
|
if (attr.IsInstruction) {
|
|
// Because of embedded instructions, we can't simply leap forward.
|
|
// [or can we?]
|
|
offset++;
|
|
} else {
|
|
Debug.Assert(attr.Length > 0);
|
|
offset += attr.Length;
|
|
}
|
|
} else if (attr.Symbol != null || mProject.HasCommentOrNote(offset)) {
|
|
// In an uncategorized area, but we want to break at this byte
|
|
// so the user or auto label doesn't get buried in the middle of
|
|
// a large chunk.
|
|
//
|
|
// This is similar to, but independent of, GroupedOffsetSetFromSelected()
|
|
// in ProjectView. This is for auto-detection, the other is for user
|
|
// selection. It's best if the two behave similarly though.
|
|
if (startOffset >= 0) {
|
|
AnalyzeRange(startOffset, offset - 1);
|
|
}
|
|
startOffset = offset;
|
|
offset++;
|
|
} else {
|
|
// This offset is uncategorized, keep gathering.
|
|
if (startOffset < 0) {
|
|
startOffset = offset;
|
|
}
|
|
offset++;
|
|
|
|
// Check to see if the address has changed from the previous entry.
|
|
if (offset < mAnattribs.Length &&
|
|
mAnattribs[offset-1].Address + 1 != mAnattribs[offset].Address) {
|
|
// Must be an ORG here. Scan previous region.
|
|
AnalyzeRange(startOffset, offset - 1);
|
|
startOffset = -1;
|
|
}
|
|
}
|
|
}
|
|
if (startOffset >= 0) {
|
|
AnalyzeRange(startOffset, mAnattribs.Length - 1);
|
|
}
|
|
}
|
|
|
|
/// <summary>
|
|
/// Analyzes a range of bytes, looking for opportunities to promote uncategorized
|
|
/// data to a more structured form.
|
|
/// </summary>
|
|
/// <param name="start">Offset of first byte in range.</param>
|
|
/// <param name="end">Offset of last byte in range.</param>
|
|
private void AnalyzeRange(int start, int end) {
|
|
// We want to identify runs of identical bytes, and runs of more than N human-
|
|
// readable characters (ASCII, high ASCII, PETSCII, whatever). There are a few
|
|
// ways to do this.
|
|
//
|
|
// The simple approach is to walk through the data from start to end, checking at
|
|
// each offset for runs of bytes matching the criteria. Because the data doesn't
|
|
// change, we can pre-analyze the data at project load time to speed things up.
|
|
//
|
|
// One approach is to put runs into TypedRangeSet (setting the type to the byte
|
|
// value so a run of 0x00 doesn't merge into an adjacent run of 0x01), and the
|
|
// various character encodings into individual RangeSets. Then, for any given
|
|
// byte address, you can query the length of a potential run directly. This could
|
|
// be made faster with a mergesort-like algorithm that walked through the various
|
|
// range sets, rather than iterating over every byte in the range. However, the
|
|
// ranges passed into this method tend to be small, so the initial setup time for
|
|
// each region can dominate the performance. (The optimized implementation of this
|
|
// approach is also fairly complicated.)
|
|
//
|
|
// A memory-hungry alternative is to create arrays of integers, one entry per byte
|
|
// in the file, and set each entry to the number of bytes in the run that would
|
|
// follow at that point. So if a run of 20 zeroes began at off set 5, you would
|
|
// set run[5]=20, run[6]=19, and so on. That avoids searching in the sets, at the
|
|
// cost of potentially several megabytes for a large 65816 file.
|
|
//
|
|
// It's even possible that Regex would handle this faster and more easily. This
|
|
// can be done fairly quickly with "unsafe" code, e.g.:
|
|
// https://stackoverflow.com/questions/3028768/net-regular-expressions-on-bytes-instead-of-chars
|
|
// https://stackoverflow.com/questions/1660694/regular-expression-to-match-any-character-being-repeated-more-than-10-times
|
|
//
|
|
// Ultimately we're just not spending that much time here. Setting
|
|
// AnalyzeUncategorizedData=false reveals that most of the time is spent in
|
|
// the caller, identifying the regions, so a significant improvement here won't
|
|
// have much impact on the user experience.
|
|
//
|
|
// Vague idea: figure out how to re-use the results from the previous analysis
|
|
// pass. At a superficial level we can cache the result of calling here with a
|
|
// particular (start, end) pair. At a higher level we may be able to avoid
|
|
// the search for uncategorized data, certainly at the bank level, possibly within
|
|
// a bank.
|
|
|
|
mDebugLog.LogI("Analyzing [+" + start.ToString("x6") + ",+" + end.ToString("x6") +"]");
|
|
|
|
FormatDescriptor oneByteDefault = FormatDescriptor.Create(1,
|
|
FormatDescriptor.Type.Default, FormatDescriptor.SubType.None);
|
|
FormatDescriptor.DebugPrefabBump(-1);
|
|
if (!mAnalysisParams.AnalyzeUncategorizedData) {
|
|
// Analysis is disabled, so just mark everything as single-byte data.
|
|
while (start <= end) {
|
|
mAnattribs[start].DataDescriptor = oneByteDefault;
|
|
FormatDescriptor.DebugPrefabBump();
|
|
start++;
|
|
}
|
|
return;
|
|
}
|
|
|
|
int minStringChars = mAnalysisParams.MinCharsForString;
|
|
|
|
#if DATA_PRESCAN // this is actually slower (and uses more memory)
|
|
while (start <= end) {
|
|
// This is used to let us skip forward. It starts past the end of the block,
|
|
// and moves backward as we identify potential points of interest.
|
|
int minNextStart = end + 1;
|
|
|
|
bool found = mProject.RepeatedBytes.GetContainingOrSubsequentRange(start,
|
|
out TypedRangeSet.TypedRange tyRange);
|
|
if (found) {
|
|
if (tyRange.Low <= start) {
|
|
// found a matching range
|
|
Debug.Assert(tyRange.Low <= start && tyRange.High >= start);
|
|
int clampEnd = Math.Min(tyRange.High, end);
|
|
int repLen = clampEnd - start + 1;
|
|
if (repLen >= MIN_RUN_LENGTH) {
|
|
bool isAscii =
|
|
TextUtil.IsPrintableAscii((char)(mFileData[start] & 0x7f));
|
|
|
|
// IF the run isn't ASCII, OR it's so long that we don't want to
|
|
// encode it as a string, OR it's so short that we don't want to
|
|
// treat it as a string, THEN output it as a run. Otherwise, just
|
|
// let the ASCII-catcher handle it later.
|
|
if (!isAscii ||
|
|
repLen > MIN_RUN_LENGTH_ASCII || repLen < minStringChars) {
|
|
LogV(start, "Run of 0x" + mFileData[start].ToString("x2") + ": " +
|
|
repLen + " bytes");
|
|
mAnattribs[start].DataDescriptor = FormatDescriptor.Create(
|
|
repLen, FormatDescriptor.Type.Fill,
|
|
FormatDescriptor.SubType.None);
|
|
start += repLen;
|
|
continue;
|
|
}
|
|
}
|
|
// We didn't like this range. We probably won't like it for any other
|
|
// point within the range, so start again past it. Ideally we'd use
|
|
// Range.Low of the range that followed the one that was returned, but
|
|
// we don't have that handy.
|
|
minNextStart = Math.Min(minNextStart, tyRange.High + 1);
|
|
} else {
|
|
// no match; try to advance to the start of the next range.
|
|
Debug.Assert(tyRange.Low > start);
|
|
minNextStart = Math.Min(minNextStart, tyRange.Low);
|
|
}
|
|
}
|
|
|
|
found = mProject.StdAsciiBytes.GetContainingOrSubsequentRange(start,
|
|
out RangeSet.Range range);
|
|
if (found) {
|
|
if (range.Low <= start) {
|
|
// found a matching range
|
|
Debug.Assert(range.Low <= start && range.High >= start);
|
|
int clampEnd = Math.Min(range.High, end);
|
|
int repLen = clampEnd - start + 1;
|
|
if (repLen >= minStringChars) {
|
|
LogV(start, "Std ASCII string, len=" + repLen + " bytes");
|
|
mAnattribs[start].DataDescriptor = FormatDescriptor.Create(repLen,
|
|
FormatDescriptor.Type.String, FormatDescriptor.SubType.None);
|
|
start += repLen;
|
|
continue;
|
|
}
|
|
|
|
minNextStart = Math.Min(minNextStart, range.High + 1);
|
|
} else {
|
|
Debug.Assert(range.Low > start);
|
|
minNextStart = Math.Min(minNextStart, range.Low);
|
|
}
|
|
}
|
|
|
|
found = mProject.HighAsciiBytes.GetContainingOrSubsequentRange(start,
|
|
out range);
|
|
if (found) {
|
|
if (range.Low <= start) {
|
|
// found a matching range
|
|
Debug.Assert(range.Low <= start && range.High >= start);
|
|
int clampEnd = Math.Min(range.High, end);
|
|
int repLen = clampEnd - start + 1;
|
|
if (repLen >= minStringChars) {
|
|
LogV(start, "High ASCII string, len=" + repLen + " bytes");
|
|
mAnattribs[start].DataDescriptor = FormatDescriptor.Create(repLen,
|
|
FormatDescriptor.Type.String, FormatDescriptor.SubType.None);
|
|
start += repLen;
|
|
continue;
|
|
}
|
|
|
|
minNextStart = Math.Min(minNextStart, range.High + 1);
|
|
} else {
|
|
Debug.Assert(range.Low > start);
|
|
minNextStart = Math.Min(minNextStart, range.Low);
|
|
}
|
|
}
|
|
|
|
// Advance to the next possible run location.
|
|
int nextStart = minNextStart > 0 ? minNextStart : start + 1;
|
|
Debug.Assert(nextStart > start);
|
|
|
|
// No runs found, output as single bytes. This is the easiest form for users
|
|
// to edit.
|
|
while (start < nextStart) {
|
|
mAnattribs[start].DataDescriptor = oneByteDefault;
|
|
FormatDescriptor.DebugPrefabBump();
|
|
start++;
|
|
}
|
|
}
|
|
#else
|
|
// Select "is printable" test. We use the extended version to include some
|
|
// control characters.
|
|
// TODO(maybe): require some *actually* printable characters in each string
|
|
CharEncoding.InclusionTest testPrintable;
|
|
FormatDescriptor.SubType baseSubType;
|
|
switch (mAnalysisParams.DefaultTextScanMode) {
|
|
case TextScanMode.LowAscii:
|
|
testPrintable = CharEncoding.IsExtendedAscii;
|
|
baseSubType = FormatDescriptor.SubType.Ascii;
|
|
break;
|
|
case TextScanMode.LowHighAscii:
|
|
testPrintable = CharEncoding.IsExtendedLowOrHighAscii;
|
|
baseSubType = FormatDescriptor.SubType.ASCII_GENERIC;
|
|
break;
|
|
case TextScanMode.C64Petscii:
|
|
testPrintable = CharEncoding.IsExtendedC64Petscii;
|
|
baseSubType = FormatDescriptor.SubType.C64Petscii;
|
|
break;
|
|
case TextScanMode.C64ScreenCode:
|
|
testPrintable = CharEncoding.IsExtendedC64ScreenCode;
|
|
baseSubType = FormatDescriptor.SubType.C64Screen;
|
|
break;
|
|
default:
|
|
Debug.Assert(false);
|
|
testPrintable = CharEncoding.IsExtendedLowOrHighAscii;
|
|
baseSubType = FormatDescriptor.SubType.ASCII_GENERIC;
|
|
break;
|
|
}
|
|
|
|
while (start <= end) {
|
|
// Check for block of repeated values.
|
|
int runLen = RecognizeRun(mFileData, start, end);
|
|
int printLen = 0;
|
|
FormatDescriptor.SubType subType = baseSubType;
|
|
|
|
if (testPrintable(mFileData[start])) {
|
|
// The run byte is printable, and the run is shorter than a line. It's
|
|
// possible the run is followed by additional printable characters, e.g.
|
|
// "*****hello". Text is easier for humans to understand, so we prefer
|
|
// that unless the run is longer than one line.
|
|
if (runLen <= MAX_STRING_RUN_LENGTH) {
|
|
// See if the run is followed by additional printable characters.
|
|
printLen = runLen;
|
|
|
|
// For LowHighAscii we allow a string to be either low or high, but it
|
|
// must be entirely one thing. Refine our test.
|
|
CharEncoding.InclusionTest refinedTest = testPrintable;
|
|
if (mAnalysisParams.DefaultTextScanMode == TextScanMode.LowHighAscii) {
|
|
if (CharEncoding.IsExtendedAscii(mFileData[start])) {
|
|
refinedTest = CharEncoding.IsExtendedAscii;
|
|
subType = FormatDescriptor.SubType.Ascii;
|
|
} else {
|
|
refinedTest = CharEncoding.IsExtendedHighAscii;
|
|
subType = FormatDescriptor.SubType.HighAscii;
|
|
}
|
|
}
|
|
for (int i = start + runLen; i <= end; i++) {
|
|
if (!refinedTest(mFileData[i])) {
|
|
break;
|
|
}
|
|
printLen++;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (printLen >= minStringChars) {
|
|
// This either a short run followed by printable characters, or just a
|
|
// (possibly very large) bunch of printable characters.
|
|
Debug.Assert(subType != FormatDescriptor.SubType.ASCII_GENERIC);
|
|
LogD(start, "Character string (" + subType + "), len=" + printLen + " bytes");
|
|
mAnattribs[start].DataDescriptor = FormatDescriptor.Create(printLen,
|
|
FormatDescriptor.Type.StringGeneric, subType);
|
|
start += printLen;
|
|
} else if (runLen >= MIN_RUN_LENGTH) {
|
|
// Didn't qualify as a string, but it's long enough to be a run.
|
|
//
|
|
// TODO(someday): allow .fill pseudo-ops to have character encoding
|
|
// sub-types, so we can ".fill 64,'*'". Easy to do here, but
|
|
// proper treatment requires tweaking data operand editor to allow
|
|
// char encoding to be specified.
|
|
LogV(start, "Run of 0x" + mFileData[start].ToString("x2") + ": " +
|
|
runLen + " bytes");
|
|
mAnattribs[start].DataDescriptor = FormatDescriptor.Create(
|
|
runLen, FormatDescriptor.Type.Fill,
|
|
FormatDescriptor.SubType.None);
|
|
start += runLen;
|
|
} else {
|
|
// Nothing useful found, output 1+ values as single bytes. This is the
|
|
// easiest form for users to edit. If we found a run, but it was too short,
|
|
// we can go ahead and mark all bytes in the run because we know the later
|
|
// matches will also be too short.
|
|
Debug.Assert(runLen > 0);
|
|
while (runLen-- != 0) {
|
|
mAnattribs[start++].DataDescriptor = oneByteDefault;
|
|
FormatDescriptor.DebugPrefabBump();
|
|
}
|
|
}
|
|
}
|
|
#endif
|
|
}
|
|
|
|
#region Static analyzer methods
|
|
|
|
/// <summary>
|
|
/// Checks for a repeated run of the same byte.
|
|
/// </summary>
|
|
/// <param name="fileData">Raw data.</param>
|
|
/// <param name="start">Offset of first byte in range.</param>
|
|
/// <param name="end">Offset of last byte in range.</param>
|
|
/// <returns>Length of run.</returns>
|
|
public static int RecognizeRun(byte[] fileData, int start, int end) {
|
|
byte first = fileData[start];
|
|
int index = start;
|
|
while (++index <= end) {
|
|
if (fileData[index] != first) {
|
|
break;
|
|
}
|
|
}
|
|
return index - start;
|
|
}
|
|
|
|
/// <summary>
|
|
/// Counts the number of low-ASCII, high-ASCII, and non-ASCII values in the
|
|
/// specified region.
|
|
/// </summary>
|
|
/// <param name="fileData">Raw data.</param>
|
|
/// <param name="start">Offset of first byte in range.</param>
|
|
/// <param name="end">Offset of last byte in range</param>
|
|
/// <param name="charTest">Character test delegate. Must match on both high and
|
|
/// low characters.</param>
|
|
/// <param name="lowVal">Set to the number of low-range characters found.</param>
|
|
/// <param name="highVal">Set to the number of high-range characters found.</param>
|
|
/// <param name="nonChar">Set to the number of non-character bytes found.</param>
|
|
public static void CountHighLowBytes(byte[] fileData, int start, int end,
|
|
CharEncoding.InclusionTest charTest,
|
|
out int lowVal, out int highVal, out int nonChar) {
|
|
lowVal = highVal = nonChar = 0;
|
|
|
|
for (int i = start; i <= end; i++) {
|
|
byte val = fileData[i];
|
|
if (!charTest(val)) {
|
|
nonChar++;
|
|
} else if ((val & 0x80) == 0) {
|
|
lowVal++;
|
|
} else {
|
|
highVal++;
|
|
}
|
|
}
|
|
}
|
|
|
|
/// <summary>
|
|
/// Counts the number of bytes that match the character test.
|
|
/// </summary>
|
|
/// <param name="fileData">Raw data.</param>
|
|
/// <param name="start">Offset of first byte in range.</param>
|
|
/// <param name="end">Offset of last byte in range.</param>
|
|
/// <param name="charTest">Character test delegate.</param>
|
|
/// <returns>Number of matching characters.</returns>
|
|
public static int CountCharacterBytes(byte[] fileData, int start, int end,
|
|
CharEncoding.InclusionTest charTest) {
|
|
int count = 0;
|
|
for (int i = start; i <= end; i++) {
|
|
if (charTest(fileData[i])) {
|
|
count++;
|
|
}
|
|
}
|
|
return count;
|
|
}
|
|
|
|
/// <summary>
|
|
/// Counts the number of null-terminated strings in the buffer.
|
|
///
|
|
/// Zero-length strings are allowed but not included in the count.
|
|
///
|
|
/// If any bad data is found, the scan aborts and returns -1.
|
|
/// </summary>
|
|
/// <param name="fileData">Raw data.</param>
|
|
/// <param name="start">Offset of first byte in range.</param>
|
|
/// <param name="end">Offset of last byte in range.</param>
|
|
/// <param name="charTest">Character test delegate.</param>
|
|
/// <param name="limitHiBit">If set, the high bit in all character must be the
|
|
/// same. Used to enforce a single encoding when "low or high ASCII" is used.</param>
|
|
/// <returns>Number of strings found, or -1 if bad data identified.</returns>
|
|
public static int RecognizeNullTerminatedStrings(byte[] fileData, int start, int end,
|
|
CharEncoding.InclusionTest charTest, bool limitHiBit) {
|
|
// Quick test.
|
|
if (fileData[end] != 0x00) {
|
|
return -1;
|
|
}
|
|
|
|
int stringCount = 0;
|
|
int expectedHiBit = -1;
|
|
int stringLen = 0;
|
|
for (int i = start; i <= end; i++) {
|
|
byte val = fileData[i];
|
|
if (val == 0x00) {
|
|
// End of string. Only update count if string wasn't empty.
|
|
if (stringLen != 0) {
|
|
stringCount++;
|
|
}
|
|
stringLen = 0;
|
|
expectedHiBit = -1;
|
|
} else {
|
|
if (limitHiBit) {
|
|
if (expectedHiBit == -1) {
|
|
// First byte in string, set hi/lo expectation.
|
|
expectedHiBit = val & 0x80;
|
|
} else if ((val & 0x80) != expectedHiBit) {
|
|
// Mixed ASCII or non-ASCII, fail.
|
|
return -1;
|
|
}
|
|
}
|
|
if (!charTest(val)) {
|
|
// Not a matching character, fail.
|
|
return -1;
|
|
}
|
|
stringLen++;
|
|
}
|
|
}
|
|
|
|
return stringCount;
|
|
}
|
|
|
|
/// <summary>
|
|
/// Counts strings prefixed with an 8-bit length.
|
|
///
|
|
/// Zero-length strings are allowed but not counted.
|
|
/// </summary>
|
|
/// <param name="fileData">Raw data.</param>
|
|
/// <param name="start">Offset of first byte in range.</param>
|
|
/// <param name="end">Offset of last byte in range.</param>
|
|
/// <param name="charTest">Character test delegate.</param>
|
|
/// <param name="limitHiBit">If set, the high bit in all character must be the
|
|
/// same. Used to enforce a single encoding when "low or high ASCII" is used.</param>
|
|
/// <returns>Number of strings found, or -1 if bad data identified.</returns>
|
|
public static int RecognizeLen8Strings(byte[] fileData, int start, int end,
|
|
CharEncoding.InclusionTest charTest, bool limitHiBit) {
|
|
int posn = start;
|
|
int remaining = end - start + 1;
|
|
int stringCount = 0;
|
|
|
|
while (remaining > 0) {
|
|
int strLen = fileData[posn++];
|
|
if (strLen > --remaining) {
|
|
// Buffer doesn't hold entire string, fail.
|
|
return -1;
|
|
}
|
|
|
|
if (strLen == 0) {
|
|
continue;
|
|
}
|
|
stringCount++;
|
|
remaining -= strLen;
|
|
|
|
int expectedHiBit = fileData[posn] & 0x80;
|
|
|
|
while (strLen-- != 0) {
|
|
byte val = fileData[posn++];
|
|
if (limitHiBit && (val & 0x80) != expectedHiBit) {
|
|
// Mixed ASCII, fail.
|
|
return -1;
|
|
}
|
|
if (!charTest(val)) {
|
|
// Not a matching character, fail.
|
|
return -1;
|
|
}
|
|
}
|
|
}
|
|
|
|
return stringCount;
|
|
}
|
|
|
|
/// <summary>
|
|
/// Counts strings prefixed with a 16-bit length.
|
|
///
|
|
/// Zero-length strings are allowed but not counted.
|
|
/// </summary>
|
|
/// <param name="fileData">Raw data.</param>
|
|
/// <param name="start">Offset of first byte in range.</param>
|
|
/// <param name="end">Offset of last byte in range.</param>
|
|
/// <param name="charTest">Character test delegate.</param>
|
|
/// <param name="limitHiBit">If set, the high bit in all character must be the
|
|
/// same. Used to enforce a single encoding when "low or high ASCII" is used.</param>
|
|
/// <returns>Number of strings found, or -1 if bad data identified.</returns>
|
|
public static int RecognizeLen16Strings(byte[] fileData, int start, int end,
|
|
CharEncoding.InclusionTest charTest, bool limitHiBit) {
|
|
int posn = start;
|
|
int remaining = end - start + 1;
|
|
int stringCount = 0;
|
|
|
|
while (remaining > 0) {
|
|
if (remaining < 2) {
|
|
// Not enough bytes for length, fail.
|
|
return -1;
|
|
}
|
|
int strLen = fileData[posn++];
|
|
strLen |= fileData[posn++] << 8;
|
|
remaining -= 2;
|
|
if (strLen > remaining) {
|
|
// Buffer doesn't hold entire string, fail.
|
|
return -1;
|
|
}
|
|
|
|
if (strLen == 0) {
|
|
continue;
|
|
}
|
|
stringCount++;
|
|
remaining -= strLen;
|
|
|
|
int expectedHiBit = fileData[posn] & 0x80;
|
|
|
|
while (strLen-- != 0) {
|
|
byte val = fileData[posn++];
|
|
if (limitHiBit && (val & 0x80) != expectedHiBit) {
|
|
// Mixed ASCII, fail.
|
|
return -1;
|
|
}
|
|
if (!charTest(val)) {
|
|
// Not a matching character, fail.
|
|
return -1;
|
|
}
|
|
}
|
|
}
|
|
|
|
return stringCount;
|
|
}
|
|
|
|
/// <summary>
|
|
/// Counts strings in Dextral Character Inverted format, meaning the high bit on the
|
|
/// last byte is the opposite of the preceding.
|
|
///
|
|
/// Each string must be at least two bytes. To reduce false-positives, we require
|
|
/// that all strings have the same hi/lo pattern.
|
|
/// </summary>
|
|
/// <remarks>
|
|
/// For C64Petscii, this will identify strings that are entirely in lower case except
|
|
/// for the last letteR, or vice-versa.
|
|
/// </remarks>
|
|
/// <param name="fileData">Raw data.</param>
|
|
/// <param name="start">Offset of first byte in range.</param>
|
|
/// <param name="end">Offset of last byte in range.</param>
|
|
/// <param name="charTest">Character test delegate.</param>
|
|
/// <returns>Number of strings found, or -1 if bad data identified.</returns>
|
|
public static int RecognizeDciStrings(byte[] fileData, int start, int end,
|
|
CharEncoding.InclusionTest charTest) {
|
|
int expectedHiBit = fileData[start] & 0x80;
|
|
int stringCount = 0;
|
|
int stringLen = 0;
|
|
|
|
// Quick test on last byte.
|
|
if ((fileData[end] & 0x80) == expectedHiBit) {
|
|
return -1;
|
|
}
|
|
|
|
for (int i = start; i <= end; i++) {
|
|
byte val = fileData[i];
|
|
if ((val & 0x80) != expectedHiBit) {
|
|
// end of string
|
|
if (stringLen == 0) {
|
|
// Got two consecutive bytes with end-marker polarity... fail.
|
|
return -1;
|
|
}
|
|
stringCount++;
|
|
stringLen = 0;
|
|
} else {
|
|
stringLen++;
|
|
}
|
|
|
|
if (!charTest((byte)(val & 0x7f))) {
|
|
// Not a matching character, fail.
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
return stringCount;
|
|
}
|
|
|
|
/// <summary>
|
|
/// Counts strings in reverse Dextral Character Inverted format, meaning the string is
|
|
/// stored in reverse order in memory, and the high bit on the first (last) byte is
|
|
/// the opposite of the rest.
|
|
///
|
|
/// Each string must be at least two bytes. To reduce false-positives, we require
|
|
/// that all strings have the same hi/lo pattern.
|
|
/// </summary>
|
|
/// <param name="fileData">Raw data.</param>
|
|
/// <param name="start">Offset of first byte in range.</param>
|
|
/// <param name="end">Offset of last byte in range.</param>
|
|
/// <returns>Number of strings found, or -1 if bad data identified.</returns>
|
|
public static int RecognizeReverseDciStrings(byte[] fileData, int start, int end) {
|
|
int expectedHiBit = fileData[end] & 0x80;
|
|
int stringCount = 0;
|
|
int stringLen = 0;
|
|
|
|
// Quick test on last (first) byte.
|
|
if ((fileData[start] & 0x80) == expectedHiBit) {
|
|
return -1;
|
|
}
|
|
|
|
for (int i = end; i >= start; i--) {
|
|
byte val = fileData[i];
|
|
if ((val & 0x80) != expectedHiBit) {
|
|
// end of string
|
|
if (stringLen == 0) {
|
|
// Got two consecutive bytes with end-marker polarity... fail.
|
|
return -1;
|
|
}
|
|
stringCount++;
|
|
stringLen = 0;
|
|
} else {
|
|
stringLen++;
|
|
}
|
|
|
|
val &= 0x7f;
|
|
if (val < 0x20 || val == 0x7f) {
|
|
// Non-ASCII, fail.
|
|
return -1;
|
|
}
|
|
}
|
|
|
|
return stringCount;
|
|
}
|
|
|
|
/// <summary>
|
|
/// Verifies that the string data is what is expected. Does not attempt to check
|
|
/// the character encoding, just the structure.
|
|
/// </summary>
|
|
/// <param name="fileData">Raw data.</param>
|
|
/// <param name="offset">Start offset of string.</param>
|
|
/// <param name="length">Length of string, including leading length and terminating
|
|
/// null bytes.</param>
|
|
/// <param name="type">Expected string type.</param>
|
|
/// <param name="failMsg">Detailed failure message.</param>
|
|
/// <returns>True if all is well.</returns>
|
|
public static bool VerifyStringData(byte[] fileData, int offset, int length,
|
|
FormatDescriptor.Type type, out string failMsg) {
|
|
failMsg = string.Empty;
|
|
|
|
switch (type) {
|
|
case FormatDescriptor.Type.StringGeneric:
|
|
case FormatDescriptor.Type.StringReverse:
|
|
return true;
|
|
case FormatDescriptor.Type.StringNullTerm:
|
|
// must end in null byte, and have no null bytes before the end
|
|
int chk = offset;
|
|
while (length-- != 0) {
|
|
byte val = fileData[chk++];
|
|
if (val == 0x00) {
|
|
if (length != 0) {
|
|
failMsg = Res.Strings.STR_VFY_NULL_INSIDE_NULL_TERM;
|
|
return false;
|
|
} else {
|
|
return true;
|
|
}
|
|
}
|
|
}
|
|
failMsg = Res.Strings.STR_VFY_MISSING_NULL_TERM;
|
|
return false;
|
|
case FormatDescriptor.Type.StringL8:
|
|
if (fileData[offset] != length - 1) {
|
|
failMsg = Res.Strings.STR_VFY_L1_LENGTH_MISMATCH;
|
|
return false;
|
|
}
|
|
return true;
|
|
case FormatDescriptor.Type.StringL16:
|
|
int len = RawData.GetWord(fileData, offset, 2, false);
|
|
if (len != length - 2) {
|
|
failMsg = Res.Strings.STR_VFY_L2_LENGTH_MISMATCH;
|
|
return false;
|
|
}
|
|
return true;
|
|
case FormatDescriptor.Type.StringDci:
|
|
if (length < 2) {
|
|
failMsg = Res.Strings.STR_VFY_DCI_SHORT;
|
|
return false;
|
|
}
|
|
byte first = (byte)(fileData[offset] & 0x80);
|
|
for (int i = offset + 1; i < offset + length - 1; i++) {
|
|
if ((fileData[i] & 0x80) != first) {
|
|
failMsg = Res.Strings.STR_VFY_DCI_MIXED_DATA;
|
|
return false;
|
|
}
|
|
}
|
|
if ((fileData[offset + length - 1] & 0x80) == first) {
|
|
failMsg = Res.Strings.STR_VFY_DCI_NOT_TERMINATED;
|
|
return false;
|
|
}
|
|
return true;
|
|
default:
|
|
Debug.Assert(false);
|
|
return false;
|
|
}
|
|
}
|
|
|
|
#endregion // Static analyzers
|
|
}
|
|
}
|
|
|
|
|
|
|
|
#if DATA_PRESCAN
|
|
/// <summary>
|
|
/// Iterator that generates a list of offsets which are not known to hold code or data.
|
|
///
|
|
/// Generates a set of integers in ascending order.
|
|
/// </summary>
|
|
private class UndeterminedValueIterator : IEnumerator {
|
|
/// <summary>
|
|
/// Index of current item, or -1 if we're not started yet.
|
|
/// </summary>
|
|
private int mCurIndex;
|
|
|
|
/// <summary>
|
|
/// Reference to Anattrib array we're iterating over.
|
|
/// </summary>
|
|
private Anattrib[] mAnattribs;
|
|
|
|
|
|
/// <summary>
|
|
/// Constructor.
|
|
/// </summary>
|
|
public UndeterminedValueIterator(Anattrib[] anattribs) {
|
|
mAnattribs = anattribs;
|
|
Reset();
|
|
}
|
|
|
|
// IEnumerator: current element
|
|
public object Current {
|
|
get {
|
|
if (mCurIndex < 0) {
|
|
// not started
|
|
return null;
|
|
}
|
|
return mCurIndex;
|
|
}
|
|
}
|
|
|
|
// IEnumerator: move to the next element, returning false if there isn't one
|
|
public bool MoveNext() {
|
|
while (++mCurIndex < mAnattribs.Length) {
|
|
Anattrib attr = mAnattribs[mCurIndex];
|
|
if (attr.IsInstructionStart) {
|
|
// skip past instruction
|
|
mCurIndex += attr.Length - 1;
|
|
} else if (attr.IsUncategorized) {
|
|
// got one
|
|
return true;
|
|
}
|
|
}
|
|
|
|
return false;
|
|
}
|
|
|
|
// IEnumerator: reset state
|
|
public void Reset() {
|
|
mCurIndex = -1;
|
|
}
|
|
}
|
|
#endif
|