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28eafef27c
Extension scripts (a/k/a "plugins") can now apply any data format supported by FormatDescriptor to inline data. In particular, it can now handle variable-length inline strings. The code analyzer verifies the string structure (e.g. null-terminated strings have exactly one null byte, at the very end). Added PluginException to carry an exception back to the plugin code, for occasions when they're doing something so wrong that we just want to smack them. Added test 2022-extension-scripts to exercise the feature.
1256 lines
57 KiB
C#
1256 lines
57 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.Collections.Generic;
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using System.Diagnostics;
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using Asm65;
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using CommonUtil;
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using PluginCommon;
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using SourceGen.Sandbox;
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namespace SourceGen {
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/// <summary>
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/// Instruction analyzer.
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///
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/// All data held in this object is transient, and will be discarded when analysis
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/// completes. All user-defined values should be held elsewhere and provided as inputs
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/// to the analyzer. Any change that merits re-analysis should be handled by creating a
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/// new instance of this object.
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///
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/// See the comments at the top of UndoableChange for a list of things that can
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/// mandate code re-analysis.
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/// </summary>
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public class CodeAnalysis {
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/// <summary>
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/// Type hints are specified by the user. The identify a region as being code
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/// or data. The code analyzer will stop at data-hinted regions, and will
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/// process any code-hinted regions during the dead-code pass.
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///
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/// The hints are not used directly by the data analyzer, but the effects they
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/// have on the Anattrib array are.
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/// </summary>
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public enum TypeHint : sbyte {
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// No hint. Default value populated in new arrays.
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NoHint = 0,
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// Byte is an instruction. If the code analyzer doesn't find this
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// naturally, it will be scanned.
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Code,
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// Byte is inline data. Execution continues "through" the byte.
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InlineData,
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// Byte is data. Execution halts.
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Data
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}
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/// <summary>
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/// Class for handling callbacks from extension scripts.
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/// </summary>
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private class ScriptSupport : MarshalByRefObject, PluginCommon.IApplication {
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private CodeAnalysis mOuter;
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public ScriptSupport(CodeAnalysis ca) {
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mOuter = ca;
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}
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/// <summary>
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/// Call this when analysis is complete, to ensure that over-active scripts
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/// can't keep doing things. (This is not part of IApplication.)
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/// </summary>
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public void Shutdown() {
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mOuter = null;
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}
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public void DebugLog(string msg) {
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mOuter.mDebugLog.LogI("PLUGIN: " + msg);
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}
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public bool SetOperandFormat(int offset, DataSubType subType, string label) {
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return mOuter.SetOperandFormat(offset, subType, label);
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}
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public bool SetInlineDataFormat(int offset, int length, DataType type,
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DataSubType subType, string label) {
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return mOuter.SetInlineDataFormat(offset, length, type, subType, label);
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}
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}
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/// <summary>
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/// Extension script manager.
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/// </summary>
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private ScriptManager mScriptManager;
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/// <summary>
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/// Local object that implements the IApplication interface for plugins.
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/// </summary>
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private ScriptSupport mScriptSupport;
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/// <summary>
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/// List of interesting plugins. If we have plugins that don't do code inlining we
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/// can ignore them. (I'm using an array instead of a List<IPlugin> as a
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/// micro-optimization; see https://stackoverflow.com/a/454923/294248 .)
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/// </summary>
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private IPlugin[] mScriptArray;
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[Flags]
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private enum PluginCap { NONE = 0, JSR = 1 << 0, JSL = 1 << 1, BRK = 1 << 2 };
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private PluginCap[] mPluginCaps;
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/// <summary>
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/// CPU to use when analyzing data.
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/// </summary>
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private CpuDef mCpuDef;
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/// <summary>
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/// Map of offsets to addresses.
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/// </summary>
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private AddressMap mAddrMap;
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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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/// Reference to type hint array, one hint per byte.
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/// </summary>
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private TypeHint[] mTypeHints;
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/// <summary>
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/// Reference to status flag override array, one entry per byte.
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/// </summary>
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private StatusFlags[] mStatusFlagOverrides;
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/// <summary>
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/// Initial status flags to use at entry points.
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/// </summary>
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private StatusFlags mEntryFlags;
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/// <summary>
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/// User-configurable analysis parameters.
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/// </summary>
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private ProjectProperties.AnalysisParameters mAnalysisParameters;
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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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/// <summary>
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/// Constructor.
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/// </summary>
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/// <param name="data">65xx code stream.</param>
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/// <param name="cpuDef">CPU definition to use when interpreting code.</param>
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/// <param name="anattribs">Anattrib array. Expected to be newly allocated, all
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/// entries set to default values.</param>
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/// <param name="addrMap">Map of offsets to addresses.</param>
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/// <param name="hints">Type hints, one per byte.</param>
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/// <param name="statusFlagOverrides">Status flag overrides for instruction-start
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/// bytes.</param>
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/// <param name="entryFlags">Status flags to use at code entry points.</param>
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/// <param name="scriptMan">Extension script manager.</param>
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/// <param name="debugLog">Object that receives debug log messages.</param>
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public CodeAnalysis(byte[] data, CpuDef cpuDef, Anattrib[] anattribs,
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AddressMap addrMap, TypeHint[] hints, StatusFlags[] statusFlagOverrides,
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StatusFlags entryFlags, ProjectProperties.AnalysisParameters parms,
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ScriptManager scriptMan, DebugLog debugLog) {
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mFileData = data;
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mCpuDef = cpuDef;
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mAnattribs = anattribs;
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mAddrMap = addrMap;
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mTypeHints = hints;
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mStatusFlagOverrides = statusFlagOverrides;
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mEntryFlags = entryFlags;
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mScriptManager = scriptMan;
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mAnalysisParameters = parms;
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mDebugLog = debugLog;
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mScriptSupport = new ScriptSupport(this);
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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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#if true
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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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#else
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private void LogD(int offset, string msg) { }
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private void LogI(int offset, string msg) { }
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private void LogW(int offset, string msg) { }
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private void LogE(int offset, string msg) { }
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#endif
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/// <summary>
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/// Analyze a blob of code and data, annotating all code areas.
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///
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/// Also identifies data embedded in code, e.g. parameter blocks following a JSR,
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/// with the help of extension scripts.
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///
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/// Failing here can leave us in a strange state, so prefer to work around unexpected
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/// inputs rather than bailing entirely.
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/// </summary>
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public void Analyze() {
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List<int> scanOffsets = new List<int>();
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mDebugLog.LogI("Analyzing code: " + mFileData.Length + " bytes, CPU=" + mCpuDef.Name);
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PrepareScripts();
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SetAddresses();
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// Set the "is data" and "is inline data" flags on anything that the user has
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// flagged as being such. This tells us to stop processing or skip over bytes
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// as we work. We don't need to flag code hints explicitly for analysis, but
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// we want to be able to display the flags in the info window.
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//
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// The data recognizers may spot additional inline data offsets as we work. This
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// can cause a race if it mis-identifies code that is also a branch target;
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// whichever marks the code first will win.
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UnpackTypeHints();
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// Find starting place, based on type hints.
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// We only set the "visited" flag on the instruction start, so if the user
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// puts a code hint in the middle of an instruction, we will find it and
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// treat it as an entry point. (This is useful for embedded instructions
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// that are branched to by code we aren't able to detect.)
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int searchStart = FindFirstUnvisitedInstruction(0);
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while (searchStart >= 0) {
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mAnattribs[searchStart].IsEntryPoint = true;
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mAnattribs[searchStart].StatusFlags = mEntryFlags;
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mAnattribs[searchStart].ApplyStatusFlags(mStatusFlagOverrides[searchStart]);
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int offset = searchStart;
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while (true) {
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bool embedded = (mAnattribs[offset].IsInstruction &&
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!mAnattribs[offset].IsVisited);
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LogI(offset, "Scan chunk (vis=" + mAnattribs[offset].IsVisited +
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" chg=" + mAnattribs[offset].IsChanged +
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(embedded ? " embedded " : "") + ")");
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AnalyzeSegment(offset, scanOffsets);
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// Did anything new get added?
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if (scanOffsets.Count == 0) {
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break;
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}
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// Pop one off the end.
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int lastItem = scanOffsets.Count - 1;
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offset = scanOffsets[lastItem];
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scanOffsets.RemoveAt(lastItem);
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}
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searchStart = FindFirstUnvisitedInstruction(searchStart);
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}
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mScriptSupport.Shutdown();
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MarkUnexecutedEmbeddedCode();
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}
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/// <summary>
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/// Prepare a list of relevant extension scripts.
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/// </summary>
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private void PrepareScripts() {
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if (mScriptManager == null) {
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// Currently happens for regression tests with no external files.
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mScriptArray = new IPlugin[0];
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mPluginCaps = new PluginCap[0];
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return;
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}
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// Include all scripts.
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mScriptArray = mScriptManager.GetAllInstances().ToArray();
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mPluginCaps = new PluginCap[mScriptArray.Length];
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for (int i = 0; i < mScriptArray.Length; i++) {
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PluginCap cap = PluginCap.NONE;
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if (mScriptArray[i] is IPlugin_InlineJsr) {
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cap |= PluginCap.JSR;
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}
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if (mScriptArray[i] is IPlugin_InlineJsl) {
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cap |= PluginCap.JSL;
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}
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if (mScriptArray[i] is IPlugin_InlineBrk) {
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cap |= PluginCap.BRK;
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}
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mPluginCaps[i] = cap;
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}
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// Prep them.
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mScriptManager.PrepareScripts(mScriptSupport);
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}
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/// <summary>
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/// Sets the address for every byte in the input.
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/// </summary>
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private void SetAddresses() {
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// The AddressMap will have at least one entry, will start at offset 0, and
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// will exactly span the file.
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foreach (AddressMap.AddressMapEntry ent in mAddrMap) {
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int addr = ent.Addr;
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for (int i = ent.Offset; i < ent.Offset + ent.Length; i++) {
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mAnattribs[i].Address = addr++;
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}
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}
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}
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/// <summary>
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/// Sets the "is xxxxx" flags on type-hinted entries, so that the code analyzer
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/// can find them easily.
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/// </summary>
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private void UnpackTypeHints() {
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Debug.Assert(mTypeHints.Length == mAnattribs.Length);
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int offset = 0;
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foreach (TypeHint hint in mTypeHints) {
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switch (hint) {
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case TypeHint.Code:
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// Set the IsInstruction flag to prevent inline data from being
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// placed here.
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OpDef op = mCpuDef.GetOpDef(mFileData[offset]);
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if (op == OpDef.OpInvalid) {
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LogI(offset, "Ignoring code hint on illegal opcode");
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} else {
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mAnattribs[offset].IsHinted = true;
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mAnattribs[offset].IsInstruction = true;
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}
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break;
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case TypeHint.Data:
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// Tells the code analyzer to stop. Does not define a data analyzer
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// "uncategorized data" boundary.
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mAnattribs[offset].IsHinted = true;
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mAnattribs[offset].IsData = true;
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break;
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case TypeHint.InlineData:
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// Tells the code analyzer to walk across these.
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mAnattribs[offset].IsHinted = true;
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mAnattribs[offset].IsInlineData = true;
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break;
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case TypeHint.NoHint:
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break;
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default:
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Debug.Assert(false);
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break;
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}
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offset++;
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}
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}
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/// <summary>
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/// Finds the first offset that is hinted as code but hasn't yet been visited.
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///
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/// This might be in the middle of an already-visited instruction.
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/// </summary>
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/// <param name="start">Offset at which to start the search.</param>
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/// <returns>Offset found.</returns>
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private int FindFirstUnvisitedInstruction(int start) {
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for (int i = start; i < mAnattribs.Length; i++) {
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if (mAnattribs[i].IsHinted && mTypeHints[i] == TypeHint.Code &&
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!mAnattribs[i].IsVisited) {
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LogD(i, "Unvisited code hint");
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if (mAnattribs[i].IsData || mAnattribs[i].IsInlineData) {
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// Maybe the user put a code hint on something that was
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// later recognized as inline data? Shouldn't have been allowed.
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LogW(i, "Weird: code hint on data/inline");
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continue;
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}
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return i;
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}
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}
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return -1;
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}
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/// <summary>
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/// Finds bits of code that are part of embedded instructions but not actually
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/// executed, and marks them as inline data.
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/// </summary>
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private void MarkUnexecutedEmbeddedCode() {
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// The problem arises when you have a line like 4C 60 EA, with a branch to the
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// middle byte. The formatter will print "JMP $EA60", then "<label> RTS", and
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// then should print NOP. The problem is that the NOP wasn't reached by the
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// code analyzer, and so isn't tagged as an instruction start. It's effectively
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// inline data, so we need to mark it that way.
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//
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// We don't have a quick way to find these, so we just run through the list.
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for (int offset = 0; offset < mFileData.Length; ) {
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if (mAnattribs[offset].IsInstructionStart) {
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int len;
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for (len = 1; len < mAnattribs[offset].Length; len++) {
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if (mAnattribs[offset + len].IsInstructionStart) {
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break;
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}
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}
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offset += len;
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} else if (mAnattribs[offset].IsInstruction) {
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// bingo
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LogI(offset, "Fixing embedded orphan");
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mAnattribs[offset].IsInstruction = false;
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mAnattribs[offset].IsInlineData = true;
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mAnattribs[offset].DataDescriptor = FormatDescriptor.Create(1,
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FormatDescriptor.Type.NumericLE, FormatDescriptor.SubType.None);
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offset++;
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} else {
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offset++;
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}
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}
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}
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/// <summary>
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/// Analyzes a code segment. A code segment is a contiguous series of instructions.
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/// We halt if we encounter a return, always-taken branch, or the end of the
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/// current address map section.
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///
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/// If we find branches to unvisited code, or previously-visited code that has
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/// different status flags, we add that to the list of offsets to scan.
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/// </summary>
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/// <param name="offset">Starting offset.</param>
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/// <param name="scanOffsets">Collection to which additional offsets of interest will
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/// be added.</param>
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private void AnalyzeSegment(int offset, List<int> scanOffsets) {
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while (offset < mFileData.Length) {
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if (mAnattribs[offset].IsVisited && !mAnattribs[offset].IsChanged) {
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// already visited, not changed; nothing to do
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LogD(offset, "Visited and not changed, bailing");
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return;
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}
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bool firstVisit = !mAnattribs[offset].IsVisited;
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// Set "visited" flag, clear "changed".
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mAnattribs[offset].IsVisited = true;
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mAnattribs[offset].IsChanged = false;
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if (mAnattribs[offset].IsData) {
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// This area was declared to be data. Go no further. This shouldn't
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// usually happen -- either we should have stopped tracing, or we
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// should have identified the data area as code.
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LogI(offset, "Code ran into data section");
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Debug.Assert(false);
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return;
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} else if (mAnattribs[offset].IsInlineData) {
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// Generally this won't happen, because we ignore branches into inline data
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// areas, we reject attempts to convert code to inline data, and we can't
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// start in an inline area because the hint is wrong. However, it's possible
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// for a JSR to a new section to be registered, and then before we get to
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// it an extension script formats the area as inline data. In that case
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// the inline data "wins", and we stop here.
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LogW(offset, "Code ran into inline data section");
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return;
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}
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// Identify the instruction, and see if it runs off the end of the file.
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// If it does, treat it as data.
|
|
OpDef op = mCpuDef.GetOpDef(mFileData[offset]);
|
|
int instrLen = op.GetLength(mAnattribs[offset].StatusFlags);
|
|
LogV(offset, "OP $" + mFileData[offset].ToString("X2") + " len=" + instrLen);
|
|
if (offset + instrLen > mFileData.Length) {
|
|
// Instruction runs off the end. It's possible we visited here before with
|
|
// short M/X flags, or some other code jumps to code embedded in our
|
|
// operand. Whatever the case, we want to clear the instruction flag from
|
|
// the first byte. We can mark it as data so subsequent passes don't
|
|
// bump into this.
|
|
LogW(offset, "Instruction runs off end of file");
|
|
mAnattribs[offset].IsInstructionStart = false;
|
|
mAnattribs[offset].IsInstruction = false;
|
|
mAnattribs[offset].IsData = true;
|
|
return;
|
|
}
|
|
if (mAnattribs[offset + instrLen -1].Address !=
|
|
mAnattribs[offset].Address + instrLen - 1) {
|
|
// Address change happened mid-instruction. Mark it as data.
|
|
LogW(offset, "Detected address change mid-instruction");
|
|
mAnattribs[offset].IsInstructionStart = false;
|
|
mAnattribs[offset].IsInstruction = false;
|
|
mAnattribs[offset].IsData = true;
|
|
return;
|
|
}
|
|
|
|
// Instruction not defined for this CPU. Treat as data.
|
|
if (op.AddrMode == OpDef.AddressMode.Unknown) {
|
|
LogW(offset, "Instruction stream encountered invalid opcode ($" +
|
|
mFileData[offset].ToString("x2") + ")");
|
|
return;
|
|
}
|
|
|
|
// Flag as start of valid instruction, and mark all bytes as instructions.
|
|
// There's a possible conflict here if the first byte is marked as an
|
|
// instruction, but bytes within the instruction are marked as data. The
|
|
// easiest thing to do here is steamroll the data flags.
|
|
//
|
|
// (To cause this, hint a 3-byte instruction as data/inline-data, then
|
|
// hint the first byte of the instruction as code.)
|
|
mAnattribs[offset].IsInstructionStart = true;
|
|
mAnattribs[offset].Length = instrLen;
|
|
for (int i = offset; i < offset + instrLen; i++) {
|
|
if (mAnattribs[i].IsData) {
|
|
LogW(i, "Stripping mid-instruction data flag");
|
|
mAnattribs[i].IsData = false;
|
|
} else if (mAnattribs[i].IsInlineData) {
|
|
LogW(i, "Stripping mid-instruction inline-data flag");
|
|
mAnattribs[i].IsInlineData = false;
|
|
}
|
|
mAnattribs[i].IsInstruction = true;
|
|
}
|
|
|
|
// Compute the effect on the status flags.
|
|
StatusFlags newFlags, condBranchTakenFlags;
|
|
if (op == OpDef.OpPLP_StackPull) {
|
|
// PLP restores flags from the stack.
|
|
newFlags = condBranchTakenFlags = GuessFlagsForPLP(offset);
|
|
} else {
|
|
op.ComputeFlagChanges(mAnattribs[offset].StatusFlags, mFileData, offset,
|
|
out newFlags, out condBranchTakenFlags);
|
|
}
|
|
|
|
// Handle stuff that won't be different on a subsequent visit.
|
|
if (firstVisit) {
|
|
// Decode the operand for instructions that reference an address. If
|
|
// the target address is within the file's address space, record the
|
|
// offset as well. This doesn't examine immediate operands.
|
|
DecodeOperandAddress(offset, op);
|
|
}
|
|
|
|
int branchOffset = -1;
|
|
bool doBranch, doContinue;
|
|
|
|
// Check for branching.
|
|
if (op.IsBranchOrSubCall) {
|
|
if (mAnattribs[offset].IsOperandOffsetDirect) {
|
|
branchOffset = mAnattribs[offset].OperandOffset;
|
|
}
|
|
if (branchOffset >= 0 && branchOffset < mFileData.Length) {
|
|
doBranch = true;
|
|
} else {
|
|
// External branch. Very common for JSR to ROM routines and JMP
|
|
// through an indirect address. Not usually expected for relative
|
|
// branches.
|
|
if (op.Effect != OpDef.FlowEffect.CallSubroutine) {
|
|
LogD(offset, "Branch goes external");
|
|
}
|
|
doBranch = false;
|
|
mAnattribs[offset].IsExternalBranch = true;
|
|
}
|
|
} else {
|
|
doBranch = false;
|
|
}
|
|
|
|
// Check continuation to next instruction.
|
|
switch (op.Effect) {
|
|
case OpDef.FlowEffect.Cont:
|
|
case OpDef.FlowEffect.CallSubroutine:
|
|
case OpDef.FlowEffect.ConditionalBranch:
|
|
doContinue = true;
|
|
break;
|
|
default:
|
|
doContinue = false;
|
|
break;
|
|
}
|
|
|
|
// Some 6502 code works around the lack of a branch-always instruction with
|
|
// a complement pair (e.g. BCC + BCS), so we don't want to continue past a branch
|
|
// always taken. The converse is also true: don't pursue a branch if it's
|
|
// never taken. An example from 6502.org:
|
|
// "... a common sequence on the 6502 family is:
|
|
// CLEAR_FLAG CLC
|
|
// DB $B0
|
|
// SET_FLAG SEC
|
|
// ROR FLAG
|
|
// RTS
|
|
// When entering via CLEAR_FLAG, the $B0 becomes a 2-cycle BCS instruction, which
|
|
// is not taken (since the carry is clear). Since BCS does not affect any flags,
|
|
// it serves, in this situation, as a two byte, two cycle NOP and provides a
|
|
// subtle, but useful way to efficiently skip the SEC instruction."
|
|
|
|
// Revise branch/cont for conditional branch instructions.
|
|
if (op.Effect == OpDef.FlowEffect.ConditionalBranch) {
|
|
OpDef.BranchTaken taken =
|
|
OpDef.IsBranchTaken(op, mAnattribs[offset].StatusFlags);
|
|
if (taken == OpDef.BranchTaken.Never) {
|
|
doBranch = false;
|
|
} else if (taken == OpDef.BranchTaken.Always) {
|
|
doContinue = false;
|
|
}
|
|
mAnattribs[offset].BranchTaken = taken;
|
|
}
|
|
|
|
// Make sure destination isn't already flagged as data.
|
|
if (doBranch) {
|
|
Debug.Assert(branchOffset >= 0);
|
|
if (mAnattribs[branchOffset].IsData || mAnattribs[branchOffset].IsInlineData) {
|
|
LogW(offset, "Ignoring branch to +" + branchOffset.ToString("x6") +
|
|
" (data region)");
|
|
doBranch = false;
|
|
branchOffset = -1;
|
|
}
|
|
}
|
|
|
|
LogV(offset, "doBranch=" + doBranch + ", doCont=" + doContinue);
|
|
|
|
if (doBranch) {
|
|
// Flag the destination offset as a branch target.
|
|
mAnattribs[branchOffset].IsBranchTarget = true;
|
|
|
|
// Merge our status flags with theirs.
|
|
StatusFlags branchStatusBefore = mAnattribs[branchOffset].StatusFlags;
|
|
mAnattribs[branchOffset].MergeStatusFlags(condBranchTakenFlags);
|
|
mAnattribs[branchOffset].ApplyStatusFlags(mStatusFlagOverrides[branchOffset]);
|
|
|
|
// If we need to (re-)scan this offset, add it to the list.
|
|
//AttribFlags branchFlags = mAnattribs[branchOffset].mAttribFlags;
|
|
bool addToScan = false;
|
|
string why;
|
|
if (!mAnattribs[branchOffset].IsVisited) {
|
|
// Not yet visited. Some flags may have been set by earlier branch.
|
|
// Merge status flags and add to scan list if not already present.
|
|
addToScan = true;
|
|
why = "(not visited)";
|
|
} else {
|
|
// Visited before. If the status flags changed, set "changed" and
|
|
// add to scan offsets.
|
|
if (branchStatusBefore != mAnattribs[branchOffset].StatusFlags) {
|
|
mAnattribs[branchOffset].IsChanged = true;
|
|
addToScan = true;
|
|
}
|
|
why = "(flags: " + branchStatusBefore + " -> " +
|
|
mAnattribs[branchOffset].StatusFlags + ")";
|
|
}
|
|
if (addToScan && !scanOffsets.Contains(branchOffset)) {
|
|
LogD(offset, "Adding " + branchOffset.ToString("x4") +
|
|
" to scan list " + why);
|
|
scanOffsets.Add(branchOffset);
|
|
}
|
|
}
|
|
|
|
// On first visit, check for BRK inline call.
|
|
if (firstVisit) {
|
|
if (op == OpDef.OpBRK_Implied) {
|
|
bool noContinue = CheckForInlineCall(op, offset, !doContinue);
|
|
if (!noContinue) {
|
|
// We're expected to continue execution past the BRK.
|
|
doContinue = true;
|
|
}
|
|
}
|
|
}
|
|
|
|
if (!doContinue) {
|
|
mAnattribs[offset].DoesNotContinue = true;
|
|
break;
|
|
} else {
|
|
mAnattribs[offset].DoesNotContinue = false;
|
|
}
|
|
|
|
// Sanity check to avoid infinite loop.
|
|
if (instrLen <= 0) {
|
|
LogE(offset, "Internal error: instruction length " + instrLen);
|
|
throw new Exception("Instruction length was " + instrLen);
|
|
}
|
|
|
|
int nextOffset = offset + instrLen;
|
|
if (nextOffset >= mFileData.Length) {
|
|
// next instruction is off the end of the file
|
|
LogW(offset, "Execution ran off the end of the file");
|
|
break;
|
|
}
|
|
|
|
// On first visit, check for JSR/JSL inline call.
|
|
if (firstVisit) {
|
|
// Currently ignoring OpDef.OpJSR_AbsIndexXInd
|
|
if (op == OpDef.OpJSR_Abs || op == OpDef.OpJSR_AbsLong) {
|
|
bool noContinue = CheckForInlineCall(op, offset, false);
|
|
if (noContinue) {
|
|
LogD(offset, "Script declared inline call no-continue");
|
|
mAnattribs[offset].DoesNotContinue = true;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Are we about to walk into inline data?
|
|
int inlineDataGapLen = 0;
|
|
while (nextOffset < mFileData.Length && mAnattribs[nextOffset].IsInlineData) {
|
|
// Skip over it to find next instruction (or next inline data chunk).
|
|
// Note Anattrib.Length==0 unless a format has been applied, so we just
|
|
// walk forward a byte at a time.
|
|
inlineDataGapLen++;
|
|
nextOffset++;
|
|
}
|
|
|
|
// Re-check after inline data advance.
|
|
if (nextOffset >= mFileData.Length) {
|
|
// next instruction is off the end of the file
|
|
LogW(offset, "Execution ran off the end of the file");
|
|
break;
|
|
}
|
|
if (mAnattribs[nextOffset].IsData) {
|
|
// Drove into a data section
|
|
LogW(offset, "Execution ran into a data area");
|
|
break;
|
|
}
|
|
|
|
// Make sure we don't "continue" across an ORG.
|
|
// NOTE: it's possible to do some crazy things with multiple ORGs that will
|
|
// cause us to misinterpret things, but I don't think that matters. What's
|
|
// important is that the code analyzer doesn't drive into a data area.
|
|
int expectedAddr = mAnattribs[offset].Address + mAnattribs[offset].Length +
|
|
inlineDataGapLen;
|
|
if (mAnattribs[nextOffset].Address != expectedAddr) {
|
|
LogW(offset, "Execution ran across address change (" +
|
|
expectedAddr.ToString("x4") + " vs. " +
|
|
mAnattribs[nextOffset].Address.ToString("x4") + ")");
|
|
break;
|
|
}
|
|
|
|
// Merge the updated status flags into the next instruction.
|
|
StatusFlags nextStatusBefore = mAnattribs[nextOffset].StatusFlags;
|
|
mAnattribs[nextOffset].MergeStatusFlags(newFlags);
|
|
mAnattribs[nextOffset].ApplyStatusFlags(mStatusFlagOverrides[nextOffset]);
|
|
|
|
// If we've already visited the next offset, and the updated status flags are
|
|
// the same as the previous status flags, then there's nothing to gain by
|
|
// continuing forward.
|
|
if (mAnattribs[nextOffset].IsVisited && !mAnattribs[nextOffset].IsChanged) {
|
|
if (nextStatusBefore == mAnattribs[nextOffset].StatusFlags) {
|
|
// Instruction has been visited, hasn't been flagged as changed,
|
|
// and our status flag merge had no effect. No need to continue
|
|
// through.
|
|
LogV(offset, "Not re-examining " + nextOffset);
|
|
break;
|
|
} else {
|
|
// We changed the flags, need to re-evaluate conditional branches.
|
|
mAnattribs[nextOffset].IsChanged = true;
|
|
}
|
|
}
|
|
|
|
offset = nextOffset;
|
|
}
|
|
}
|
|
|
|
/// <summary>
|
|
/// Attempts to guess what the flags will be after a PLP instruction.
|
|
/// </summary>
|
|
/// <param name="plpOffset">Offset of PLP instruction.</param>
|
|
/// <returns>Best guess at status flags.</returns>
|
|
private StatusFlags GuessFlagsForPLP(int plpOffset) {
|
|
// We're not tracking stack contents or register contents, so this just
|
|
// generally won't work. However, there's a lot of code that uses PHP to
|
|
// save the current state and PLP to restore it, so if we can find a nearby
|
|
// PHP we can just grab from that.
|
|
//
|
|
// Failing that, we mark all flags as "indeterminate" and let the user sort
|
|
// out what it should be. It's unlikely to matter except for M/X flags on
|
|
// the 65816.
|
|
//
|
|
// The emulation flag is not part of the status register, even if we do carry
|
|
// it around like one. The E-flag is always carried over from the previous
|
|
// instruction.
|
|
|
|
int backOffsetLimit = plpOffset - 128; // arbitrary 128-byte reach
|
|
if (backOffsetLimit < 0) {
|
|
backOffsetLimit = 0;
|
|
}
|
|
StatusFlags flags = StatusFlags.AllIndeterminate;
|
|
if (mAnalysisParameters.SmartPlpHandling) {
|
|
for (int offset = plpOffset - 1; offset >= backOffsetLimit; offset--) {
|
|
Anattrib attr = mAnattribs[offset];
|
|
if (!attr.IsInstructionStart || !attr.IsVisited) {
|
|
continue;
|
|
}
|
|
OpDef op = mCpuDef.GetOpDef(mFileData[offset]);
|
|
if (op == OpDef.OpPHP_StackPush) {
|
|
LogI(plpOffset, "Found visited PHP at +" + offset.ToString("x6"));
|
|
flags = mAnattribs[offset].StatusFlags;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
|
|
// Transfer the 'E' flag.
|
|
flags.E = mAnattribs[plpOffset].StatusFlags.E;
|
|
return flags;
|
|
}
|
|
|
|
/// <summary>
|
|
/// Extracts the address from the operand of an absolute or relative operation.
|
|
/// Anything that could be referenced by a label or address equate is appropriate.
|
|
/// The goal is to identify data and branch targets, not generate a second copy
|
|
/// of the operand.
|
|
///
|
|
/// The operand's address, and if applicable, the operand's file offset, are
|
|
/// stored in the Anattrib array.
|
|
///
|
|
/// For PC-relative operands (e.g. branches) it's tempting to simply adjust the file
|
|
/// offset by the specified amount and convert that to an address. If the file
|
|
/// has multiple ORGs, this can produce incorrect results. We need to convert the
|
|
/// opcode's offset to an address, adjust by the operand, and then find the file
|
|
/// offset that corresponds to the target address.
|
|
///
|
|
/// Doesn't do anything with immediate data.
|
|
/// </summary>
|
|
/// <param name="offset">Offset of the instruction opcode.</param>
|
|
/// <param name="op">Opcode being handled. (Passed in because the caller has it
|
|
/// handy.)</param>
|
|
private void DecodeOperandAddress(int offset, OpDef op) {
|
|
//StatusFlags flags = mAnattribs[offset].StatusFlags;
|
|
|
|
int operand = op.GetOperand(mFileData, offset, mAnattribs[offset].StatusFlags);
|
|
|
|
// Add the bank to get a 24-bit address. We're currently using the program bank
|
|
// (K) rather than the data bank (B), which is correct for absolute and relative
|
|
// branches but wrong for 16-bit data operations. We currently have no way to
|
|
// know what the value of B is, so we use K because there's some small chance
|
|
// of it being correct.
|
|
// TODO(someday): figure out how to get the correct value for the B reg
|
|
int bank = mAnattribs[offset].Address & 0x7fff0000;
|
|
|
|
// Extract target address.
|
|
switch (op.AddrMode) {
|
|
// These might refer to a location in the file, or might be external.
|
|
case OpDef.AddressMode.Abs:
|
|
case OpDef.AddressMode.AbsIndexX:
|
|
case OpDef.AddressMode.AbsIndexY:
|
|
case OpDef.AddressMode.AbsIndexXInd:
|
|
case OpDef.AddressMode.AbsInd:
|
|
case OpDef.AddressMode.AbsIndLong:
|
|
case OpDef.AddressMode.StackAbs:
|
|
mAnattribs[offset].OperandAddress = operand | bank;
|
|
break;
|
|
case OpDef.AddressMode.DP:
|
|
case OpDef.AddressMode.DPIndexX:
|
|
case OpDef.AddressMode.DPIndexY:
|
|
case OpDef.AddressMode.DPIndexXInd:
|
|
case OpDef.AddressMode.DPInd:
|
|
case OpDef.AddressMode.DPIndLong:
|
|
case OpDef.AddressMode.DPIndIndexY:
|
|
case OpDef.AddressMode.DPIndIndexYLong:
|
|
case OpDef.AddressMode.StackDPInd:
|
|
// always bank 0
|
|
mAnattribs[offset].OperandAddress = operand;
|
|
break;
|
|
case OpDef.AddressMode.AbsIndexXLong:
|
|
case OpDef.AddressMode.AbsLong:
|
|
// 24-bit address, don't add bank
|
|
mAnattribs[offset].OperandAddress = operand;
|
|
break;
|
|
case OpDef.AddressMode.PCRel: // rel operand; convert to absolute addr
|
|
mAnattribs[offset].OperandAddress =
|
|
Asm65.Helper.RelOffset8(mAnattribs[offset].Address,
|
|
(sbyte)operand) | bank;
|
|
break;
|
|
case OpDef.AddressMode.PCRelLong:
|
|
case OpDef.AddressMode.StackPCRelLong:
|
|
mAnattribs[offset].OperandAddress =
|
|
Asm65.Helper.RelOffset16(mAnattribs[offset].Address,
|
|
(short)operand) | bank;
|
|
break;
|
|
default:
|
|
// Immediate, implied, accumulator, stack relative. We can't do
|
|
// immediate yet because we won't necessarily have a final assessment
|
|
// of the operand width.
|
|
Debug.Assert(mAnattribs[offset].OperandAddress == -1);
|
|
break;
|
|
}
|
|
|
|
if (mAnattribs[offset].OperandAddress >= 0) {
|
|
int operandOffset = mAddrMap.AddressToOffset(offset,
|
|
mAnattribs[offset].OperandAddress);
|
|
if (operandOffset >= 0) {
|
|
mAnattribs[offset].OperandOffset = operandOffset;
|
|
|
|
// Set a flag if this is a direct offset. This is used when tracing
|
|
// through jump instructions, as we can't necessarily decode an indirect
|
|
// jump. (There are *some* indirect JMPs we can handle, if the operand
|
|
// is an address in the file data area.)
|
|
switch (op.AddrMode) {
|
|
case OpDef.AddressMode.Abs:
|
|
case OpDef.AddressMode.AbsLong:
|
|
case OpDef.AddressMode.DP:
|
|
case OpDef.AddressMode.PCRel:
|
|
case OpDef.AddressMode.PCRelLong:
|
|
case OpDef.AddressMode.StackPCRelLong:
|
|
case OpDef.AddressMode.StackAbs:
|
|
mAnattribs[offset].IsOperandOffsetDirect = true;
|
|
break;
|
|
default:
|
|
mAnattribs[offset].IsOperandOffsetDirect = false;
|
|
break;
|
|
}
|
|
}
|
|
} else {
|
|
Debug.Assert(mAnattribs[offset].OperandOffset == -1);
|
|
Debug.Assert(!mAnattribs[offset].IsOperandOffsetDirect);
|
|
}
|
|
}
|
|
|
|
/// <summary>
|
|
/// Queries script extensions to check to see if a JSR or JSL is actually an inline call.
|
|
/// </summary>
|
|
/// <param name="op">Instruction being examined.</param>
|
|
/// <param name="offset">File offset of start of instruction.</param>
|
|
/// <param name="noContinue">Set if any plugin declares the call to be no-continue.</param>
|
|
/// <returns>Updated value for noContinue.</returns>
|
|
private bool CheckForInlineCall(OpDef op, int offset, bool noContinue) {
|
|
for (int i = 0; i < mScriptArray.Length; i++) {
|
|
try {
|
|
IPlugin script = mScriptArray[i];
|
|
// The IPlugin object is a MarshalByRefObject, which doesn't define the
|
|
// interface directly. A simple test showed it was fairly quick when the
|
|
// interface was implemented but a bit slow when it wasn't. For performance
|
|
// we query the capability flags instead.
|
|
if (op == OpDef.OpJSR_Abs && (mPluginCaps[i] & PluginCap.JSR) != 0) {
|
|
((IPlugin_InlineJsr)script).CheckJsr(offset, out bool noCont);
|
|
noContinue |= noCont;
|
|
} else if (op == OpDef.OpJSR_AbsLong && (mPluginCaps[i] & PluginCap.JSL) != 0) {
|
|
((IPlugin_InlineJsl)script).CheckJsl(offset, out bool noCont);
|
|
noContinue |= noCont;
|
|
} else if (op == OpDef.OpBRK_Implied && (mPluginCaps[i] & PluginCap.BRK) != 0) {
|
|
((IPlugin_InlineBrk)script).CheckBrk(offset, out bool noCont);
|
|
noContinue &= noCont;
|
|
}
|
|
} catch (PluginException plex) {
|
|
LogW(offset, "Uncaught PluginException: " + plex.Message);
|
|
} catch (Exception ex) {
|
|
LogW(offset, "Plugin threw exception: " + ex);
|
|
}
|
|
}
|
|
return noContinue;
|
|
}
|
|
|
|
/// <summary>
|
|
/// Sets the format of an instruction operand.
|
|
/// </summary>
|
|
/// <param name="offset">Offset of opcode.</param>
|
|
/// <param name="subType">Format sub-type.</param>
|
|
/// <param name="label">Label, for subType=Symbol.</param>
|
|
/// <returns>True if the format was applied.</returns>
|
|
private bool SetOperandFormat(int offset, DataSubType subType, string label) {
|
|
if (offset <= 0 || offset > mFileData.Length) {
|
|
throw new PluginException("SOF: bad args: offset=+" + offset.ToString("x6") +
|
|
" subType=" + subType + " label='" + label + "'; file length is" +
|
|
mFileData.Length);
|
|
}
|
|
|
|
// Don't overwrite existing format.
|
|
if (mAnattribs[offset].DataDescriptor != null) {
|
|
LogW(offset, "SOF: already have a descriptor here");
|
|
return false;
|
|
}
|
|
|
|
// Must be the start of an instruction.
|
|
if (!mAnattribs[offset].IsInstructionStart) {
|
|
LogW(offset, "SOF: not an instruction start");
|
|
return false;
|
|
}
|
|
|
|
if (subType == DataSubType.Symbol && string.IsNullOrEmpty(label)) {
|
|
LogW(offset, "SOF rej: label required for subType=" + subType);
|
|
return false;
|
|
}
|
|
|
|
FormatDescriptor.SubType subFmt = ConvertPluginSubType(subType, out bool isStringSub);
|
|
if (subFmt == FormatDescriptor.SubType.None) {
|
|
LogW(offset, "SOF: bad sub-type " + subType);
|
|
return false;
|
|
}
|
|
|
|
int instrLen = mAnattribs[offset].Length;
|
|
Debug.Assert(instrLen > 0);
|
|
|
|
FormatDescriptor fd;
|
|
if (subType == DataSubType.Symbol) {
|
|
fd = FormatDescriptor.Create(instrLen,
|
|
new WeakSymbolRef(label, WeakSymbolRef.Part.Low),
|
|
false);
|
|
} else {
|
|
fd = FormatDescriptor.Create(instrLen, FormatDescriptor.Type.NumericLE, subFmt);
|
|
}
|
|
mAnattribs[offset].DataDescriptor = fd;
|
|
return true;
|
|
}
|
|
|
|
/// <summary>
|
|
/// Handles a set inline data format call from an extension script.
|
|
/// </summary>
|
|
/// <param name="offset">Offset of start of data item.</param>
|
|
/// <param name="length">Length of data item. Must be greater than zero.</param>
|
|
/// <param name="type">Data type.</param>
|
|
/// <param name="subType">Data sub-type.</param>
|
|
/// <param name="label">Label, for type=Symbol.</param>
|
|
private bool SetInlineDataFormat(int offset, int length, DataType type,
|
|
DataSubType subType, string label) {
|
|
if (offset <= 0 || length <= 0 || offset + length > mFileData.Length) {
|
|
throw new PluginException("SIDF: bad args: offset=+" + offset.ToString("x6") +
|
|
" len=" + length + " type=" + type + " subType=" + subType +
|
|
" label='" + label + "'; file length is" + mFileData.Length);
|
|
}
|
|
|
|
if (!mAddrMap.IsContiguous(offset, length)) {
|
|
LogW(offset, "SIDF: format crosses address map boundary (len=" + length + ")");
|
|
return false;
|
|
}
|
|
|
|
// Already formatted? We only check the initial offset -- overlapping format
|
|
// descriptors aren't strictly illegal.
|
|
if (mAnattribs[offset].DataDescriptor != null) {
|
|
LogW(offset, "SIDF: already have a descriptor here");
|
|
return false;
|
|
}
|
|
|
|
// Don't allow formatting of any bytes that are identified as instructions or
|
|
// were hinted by the user as something other than inline data. If the code
|
|
// analyzer comes crashing through later they'll just stomp on what we've done.
|
|
for (int i = offset; i < offset + length; i++) {
|
|
if (mTypeHints[i] != TypeHint.NoHint && mTypeHints[i] != TypeHint.InlineData) {
|
|
LogW(offset, "SIDF rej: already a hint at " + i.ToString("x6") +
|
|
" (" + mTypeHints[i] + ")");
|
|
return false;
|
|
}
|
|
if (mAnattribs[offset].IsInstruction) {
|
|
LogW(offset, "SIDF rej: not for use with instructions");
|
|
return false;
|
|
}
|
|
}
|
|
|
|
//
|
|
// Convert types to FormatDescriptor types, and do some validity checks.
|
|
//
|
|
FormatDescriptor.Type fmt = ConvertPluginType(type, out bool isStringType);
|
|
FormatDescriptor.SubType subFmt = ConvertPluginSubType(subType, out bool isStringSub);
|
|
|
|
if (type == DataType.Dense && subType != DataSubType.None) {
|
|
throw new PluginException("SIDF rej: dense data must use subType=None");
|
|
}
|
|
if (type == DataType.Fill && subType != DataSubType.None) {
|
|
throw new PluginException("SIDF rej: fill data must use subType=None");
|
|
}
|
|
|
|
if (isStringType && !isStringSub) {
|
|
throw new PluginException("SIDF rej: bad type/subType combo: type=" +
|
|
type + " subType= " + subType);
|
|
}
|
|
if ((type == DataType.NumericLE || type == DataType.NumericBE) &&
|
|
(length < 1 || length > 4)) {
|
|
throw new PluginException("SIDF rej: bad length for numeric item (" +
|
|
length + ")");
|
|
}
|
|
if (subType == DataSubType.Symbol && string.IsNullOrEmpty(label)) {
|
|
throw new PluginException("SIDF rej: label required for subType=" + subType);
|
|
}
|
|
|
|
if (isStringType) {
|
|
if (!VerifyStringData(offset, length, fmt)) {
|
|
return false;
|
|
}
|
|
} else if (type == DataType.Fill) {
|
|
if (!VerifyFillData(offset, length)) {
|
|
return false;
|
|
}
|
|
}
|
|
|
|
// Looks good, create a descriptor, and mark all bytes as inline data.
|
|
FormatDescriptor fd;
|
|
if (subType == DataSubType.Symbol) {
|
|
fd = FormatDescriptor.Create(length,
|
|
new WeakSymbolRef(label, WeakSymbolRef.Part.Low),
|
|
type == DataType.NumericBE);
|
|
} else {
|
|
fd = FormatDescriptor.Create(length, fmt, subFmt);
|
|
}
|
|
mAnattribs[offset].DataDescriptor = fd;
|
|
for (int i = offset; i < offset + length; i++) {
|
|
mAnattribs[i].IsInlineData = true;
|
|
}
|
|
return true;
|
|
}
|
|
|
|
/// <summary>
|
|
/// Verifies that the string data is what is expected. Does not attempt to check
|
|
/// the character encoding, just the structure.
|
|
/// </summary>
|
|
/// <returns>True if all is well.</returns>
|
|
private bool VerifyStringData(int offset, int length, FormatDescriptor.Type type) {
|
|
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 = mFileData[chk++];
|
|
if (val == 0x00) {
|
|
if (length != 0) {
|
|
LogW(offset, "found null in middle of null-term string");
|
|
return false;
|
|
} else {
|
|
return true;
|
|
}
|
|
}
|
|
}
|
|
LogW(offset, "no null at end of null-term string");
|
|
return false;
|
|
case FormatDescriptor.Type.StringL8:
|
|
if (mFileData[offset] != length - 1) {
|
|
LogW(offset, "L1 string with mismatched length");
|
|
return false;
|
|
}
|
|
return true;
|
|
case FormatDescriptor.Type.StringL16:
|
|
int len = RawData.GetWord(mFileData, offset, 2, false);
|
|
if (len != length - 2) {
|
|
LogW(offset, "L2 string with mismatched length");
|
|
return false;
|
|
}
|
|
return true;
|
|
case FormatDescriptor.Type.StringDci:
|
|
if (length < 2) {
|
|
LogW(offset, "DCI string is too short");
|
|
return false;
|
|
}
|
|
byte first = (byte) (mFileData[offset] & 0x80);
|
|
for (int i = offset + 1; i < offset + length - 1; i++) {
|
|
if ((mFileData[i] & 0x80) != first) {
|
|
LogW(offset, "mixed DCI string");
|
|
return false;
|
|
}
|
|
}
|
|
if ((mFileData[offset + length - 1] & 0x80) == first) {
|
|
LogW(offset, "DCI string did not end");
|
|
return false;
|
|
}
|
|
return true;
|
|
default:
|
|
Debug.Assert(false);
|
|
return false;
|
|
}
|
|
}
|
|
|
|
private bool VerifyFillData(int offset, int length) {
|
|
byte first = mFileData[offset];
|
|
while (--length != 0) {
|
|
if (mFileData[++offset] != first) {
|
|
LogW(offset, "SIDF: mismatched fill data");
|
|
return false;
|
|
}
|
|
}
|
|
return true;
|
|
}
|
|
|
|
private FormatDescriptor.Type ConvertPluginType(DataType pluginType,
|
|
out bool isStringType) {
|
|
isStringType = false;
|
|
switch (pluginType) {
|
|
case DataType.NumericLE:
|
|
return FormatDescriptor.Type.NumericLE;
|
|
case DataType.NumericBE:
|
|
return FormatDescriptor.Type.NumericBE;
|
|
case DataType.StringGeneric:
|
|
isStringType = true;
|
|
return FormatDescriptor.Type.StringGeneric;
|
|
case DataType.StringReverse:
|
|
isStringType = true;
|
|
return FormatDescriptor.Type.StringReverse;
|
|
case DataType.StringNullTerm:
|
|
isStringType = true;
|
|
return FormatDescriptor.Type.StringNullTerm;
|
|
case DataType.StringL8:
|
|
isStringType = true;
|
|
return FormatDescriptor.Type.StringL8;
|
|
case DataType.StringL16:
|
|
isStringType = true;
|
|
return FormatDescriptor.Type.StringL16;
|
|
case DataType.StringDci:
|
|
isStringType = true;
|
|
return FormatDescriptor.Type.StringDci;
|
|
case DataType.Fill:
|
|
return FormatDescriptor.Type.Fill;
|
|
case DataType.Dense:
|
|
return FormatDescriptor.Type.Dense;
|
|
default:
|
|
Debug.Assert(false);
|
|
throw new PluginException("Instr format rej: unknown format type " + pluginType);
|
|
}
|
|
}
|
|
|
|
private FormatDescriptor.SubType ConvertPluginSubType(DataSubType pluginSubType,
|
|
out bool isStringSub) {
|
|
isStringSub = false;
|
|
switch (pluginSubType) {
|
|
case DataSubType.None:
|
|
return FormatDescriptor.SubType.None;
|
|
case DataSubType.Hex:
|
|
return FormatDescriptor.SubType.Hex;
|
|
case DataSubType.Decimal:
|
|
return FormatDescriptor.SubType.Decimal;
|
|
case DataSubType.Binary:
|
|
return FormatDescriptor.SubType.Binary;
|
|
case DataSubType.Address:
|
|
return FormatDescriptor.SubType.Address;
|
|
case DataSubType.Symbol:
|
|
return FormatDescriptor.SubType.Symbol;
|
|
case DataSubType.Ascii:
|
|
isStringSub = true;
|
|
return FormatDescriptor.SubType.Ascii;
|
|
case DataSubType.HighAscii:
|
|
isStringSub = true;
|
|
return FormatDescriptor.SubType.HighAscii;
|
|
case DataSubType.C64Petscii:
|
|
isStringSub = true;
|
|
return FormatDescriptor.SubType.C64Petscii;
|
|
case DataSubType.C64Screen:
|
|
isStringSub = true;
|
|
return FormatDescriptor.SubType.C64Screen;
|
|
default:
|
|
throw new PluginException("Instr format rej: unknown sub type " + pluginSubType);
|
|
}
|
|
}
|
|
}
|
|
} |