Add offset to PlSymbol

It's useful for extension scripts to be able to get the file offset
of symbols in non-addressable regions.  One example of this is CHR
ROM data for an NES cartridge.  However, we were getting the offset
by doing an address-to-offset mapping on the plugin side, which by
definition doesn't work for non-addressable memory.

So we now add the offset to PlSymbol objects for user labels and
address region pre-labels.  The NES visualizer has been updated to
use the new field.

Also, fixed a bogus complaint about bank overruns for non-addressable
regions.

PluginCommon/PlSymbol.cs

@@ -81,6 +81,11 @@ namespace PluginCommon {
         /// </summary>
         public string Tag { get; private set; }
 
+        /// <summary>
+        /// Symbol offset, for user labels and pre-labels; -1 otherwise.
+        /// </summary>
+        public int Offset { get; private set; }
+
 
         /// <summary>
         /// Nullary constructor, for deserialization.
@@ -92,14 +97,20 @@ namespace PluginCommon {
         /// </summary>
         /// <param name="label">Symbol label.</param>
         /// <param name="value">Symbol value.</param>
+        /// <param name="width">Width, for platform/project symbols.</param>
+        /// <param name="source">Symbol source.</param>
+        /// <param name="type">Symbol type.</param>
         /// <param name="tag">Symbol group tag.</param>
-        public PlSymbol(string label, int value, int width, Source source, Type type, string tag) {
+        /// <param name="offset">Offset, for user labels and pre-labels; -1 otherwise.</param>
+        public PlSymbol(string label, int value, int width, Source source, Type type, string tag,
+                int offset) {
             Label = label;
             Value = value;
             Width = width;
             SymbolSource = source;
             SymbolType = type;
             Tag = tag;
+            Offset = offset;
         }
 
         /// <summary>

SourceGen/AsmGen/GenCommon.cs

@@ -407,6 +407,10 @@ namespace SourceGen.AsmGen {
             if (attr.Length != instrBytes) {
                 // This instruction has another instruction inside it.  Throw out what we
                 // computed and just output as bytes.
+                // TODO: in some odd situations we can split something that doesn't need
+                //   to be split (see note at end of #107).  Working around the problem at
+                //   this stage is a little awkward because I think we need to check for the
+                //   presence of labels on one or more later lines.
                 gen.GenerateShortSequence(offset, instrBytes, out opcodeStr, out operandStr);
             } else if (isPcRelBankWrap && gen.Quirks.NoPcRelBankWrap) {
                 // Some assemblers have trouble generating PC-relative operands that wrap

SourceGen/DisasmProject.cs

@@ -759,7 +759,7 @@ namespace SourceGen {
             IEnumerator<AddressMap.AddressChange> addrIter = AddrMap.AddressChangeIterator;
             while (addrIter.MoveNext()) {
                 AddressMap.AddressChange change = addrIter.Current;
-                if (!change.IsStart) {
+                if (!change.IsStart || change.Address == Address.NON_ADDR) {
                     continue;
                 }
                 AddressMap.AddressRegion region = change.Region;
@@ -1552,46 +1552,7 @@ namespace SourceGen {
                 }
             }
 
-            // Create a mapping from label (which must be unique) to file offset.  This
+            SortedList<string, int> labelList = CreateLabelToOffsetMap();
-            // is different from UserLabels (which only has user-created labels, and is
-            // sorted by offset) and SymbolTable (which has constants and platform symbols,
-            // and uses the address as the value rather than the offset).
-            SortedList<string, int> labelList = new SortedList<string, int>(mFileData.Length,
-                Asm65.Label.LABEL_COMPARER);
-            for (int offset = 0; offset < mAnattribs.Length; offset++) {
-                Anattrib attr = mAnattribs[offset];
-                if (attr.Symbol != null) {
-                    try {
-                        labelList.Add(attr.Symbol.Label, offset);
-                    } catch (ArgumentException ex) {
-                        // Duplicate UserLabel entries are stripped when projects are loaded, but
-                        // it might be possible to cause this by hiding/unhiding a label (e.g.
-                        // using a code start tag to place it in the middle of an instruction).
-                        // Just ignore the duplicate.
-                        Debug.WriteLine("Xref ignoring duplicate label '" + attr.Symbol.Label +
-                            "': " + ex.Message);
-                    }
-                }
-            }
-            // Add all valid address region pre-labels.  Duplicates of user labels will be
-            // rejected.  Note the references will appear on the line for the next file offset,
-            // not the pre-label itself, because we need to associate it with a file offset.
-            IEnumerator<AddressMap.AddressChange> addrIter = AddrMap.AddressChangeIterator;
-            while (addrIter.MoveNext()) {
-                AddressMap.AddressChange change = addrIter.Current;
-                if (!change.IsStart) {
-                    continue;
-                }
-                if (change.Region.HasValidPreLabel) {
-                    try {
-                        labelList.Add(change.Region.PreLabel, change.Region.Offset);
-                    } catch (ArgumentException ex) {
-                        Debug.WriteLine("Xref ignoring pre-label duplicate '" +
-                            change.Region.PreLabel + "': " + ex.Message);
-                    }
-
-                }
-            }
 
             // No particular reason to do this here, but it's convenient.
             ByteCounts.Reset();
@@ -1802,6 +1763,54 @@ namespace SourceGen {
             return xset;        // will be null if not found
         }
 
+        /// <summary>
+        /// Creates a mapping from label (which must be unique) to file offset.  This
+        /// is different from UserLabels (which only has user-created labels, and is
+        /// sorted by offset) and SymbolTable (which has constants and platform symbols,
+        /// and uses the address as the value rather than the offset).
+        ///
+        /// We use Anattribs to ensure that we only include visible labels.
+        /// </summary>
+        private SortedList<string, int> CreateLabelToOffsetMap() {
+            SortedList<string, int> labelList = new SortedList<string, int>(mFileData.Length,
+                Asm65.Label.LABEL_COMPARER);
+            for (int offset = 0; offset < mAnattribs.Length; offset++) {
+                Anattrib attr = mAnattribs[offset];
+                if (attr.Symbol != null) {
+                    try {
+                        labelList.Add(attr.Symbol.Label, offset);
+                    } catch (ArgumentException ex) {
+                        // Duplicate UserLabel entries are stripped when projects are loaded, but
+                        // it might be possible to cause this by hiding/unhiding a label (e.g.
+                        // using a code start tag to place it in the middle of an instruction).
+                        // Just ignore the duplicate.
+                        Debug.WriteLine("Xref ignoring duplicate label '" + attr.Symbol.Label +
+                            "': " + ex.Message);
+                    }
+                }
+            }
+            // Add all valid address region pre-labels.  Duplicates of user labels will be
+            // rejected.  Note the references will appear on the line for the next file offset,
+            // not the pre-label itself, because we need to associate it with a file offset.
+            IEnumerator<AddressMap.AddressChange> addrIter = AddrMap.AddressChangeIterator;
+            while (addrIter.MoveNext()) {
+                AddressMap.AddressChange change = addrIter.Current;
+                if (!change.IsStart) {
+                    continue;
+                }
+                if (change.Region.HasValidPreLabel) {
+                    try {
+                        labelList.Add(change.Region.PreLabel, change.Region.Offset);
+                    } catch (ArgumentException ex) {
+                        Debug.WriteLine("Xref ignoring pre-label duplicate '" +
+                            change.Region.PreLabel + "': " + ex.Message);
+                    }
+
+                }
+            }
+            return labelList;
+        }
+
         /// <summary>
         /// Replaces generic auto-labels with fancier versions generated from xrefs.
         /// </summary>

SourceGen/MainController.cs

@@ -3177,7 +3177,7 @@ namespace SourceGen {
         public void GoToLabel(Symbol sym) {
             int offset = mProject.FindLabelOffsetByName(sym.Label);
             if (offset >= 0) {
-                // TODO(someday): jump to correct line for address region pre-labels
+                // TODO(someday): jump to symbol line, not arstart, for address region pre-labels
                 GoToLocation(new NavStack.Location(offset, 0, NavStack.GoToMode.JumpToCodeData),
                     true);
             } else {

SourceGen/RuntimeData/Nintendo/VisNES.cs

@@ -115,8 +115,7 @@ namespace RuntimeData.Nintendo {
 
             foreach (PlSymbol sym in plSyms) {
                 if (sym.Label == CHR_ROM) {
-                    int addr = sym.Value;
+                    mChrRomOffset = sym.Offset;
-                    mChrRomOffset = mAddrTrans.AddressToOffset(0, addr);
                     break;
                 }
             }

SourceGen/Sandbox/ScriptManager.cs

@@ -327,18 +327,51 @@ namespace SourceGen.Sandbox {
         /// <summary>
         /// Gathers a list of symbols from the project's symbol table.
         /// </summary>
+        /// <remarks>
+        /// Remember that we need to set this up before code analysis runs, so many of the
+        /// secondary data structures (like Anattribs) won't be available.
+        /// </remarks>
         private List<PlSymbol> GeneratePlSymbolList() {
             List<PlSymbol> plSymbols = new List<PlSymbol>();
             SymbolTable symTab = mProject.SymbolTable;
 
+            // UserLabels maps offset to Symbol.  Create the reverse mapping.
+            Dictionary<Symbol, int> symbolOffsets =
+                new Dictionary<Symbol, int>(mProject.UserLabels.Count);
+            foreach (KeyValuePair<int, Symbol> kvp in mProject.UserLabels) {
+                symbolOffsets[kvp.Value] = kvp.Key;
+            }
+
+            // Add in the address region pre-labels.
+            IEnumerator<AddressMap.AddressChange> addrIter = mProject.AddrMap.AddressChangeIterator;
+            while (addrIter.MoveNext()) {
+                AddressMap.AddressChange change = addrIter.Current;
+                if (!change.IsStart) {
+                    continue;
+                }
+                if (change.Region.HasValidPreLabel) {
+                    Symbol newSym = new Symbol(change.Region.PreLabel,
+                        change.Region.PreLabelAddress, Symbol.Source.AddrPreLabel,
+                        Symbol.Type.ExternalAddr, Symbol.LabelAnnotation.None);
+                    symbolOffsets[newSym] = change.Region.Offset;
+                }
+            }
+
             foreach (Symbol sym in symTab) {
                 PlSymbol.Source plsSource;
+                int symOff, offset = -1;
                 switch (sym.SymbolSource) {
                     case Symbol.Source.User:
                         plsSource = PlSymbol.Source.User;
+                        if (symbolOffsets.TryGetValue(sym, out symOff)) {
+                            offset = symOff;
+                        }
                         break;
                     case Symbol.Source.AddrPreLabel:
                         plsSource = PlSymbol.Source.AddrPreLabel;
+                        if (symbolOffsets.TryGetValue(sym, out symOff)) {
+                            offset = symOff;
+                        }
                         break;
                     case Symbol.Source.Project:
                         plsSource = PlSymbol.Source.Project;
@@ -381,8 +414,8 @@ namespace SourceGen.Sandbox {
                     tag = defSym.Tag;
                 }
 
-
+                plSymbols.Add(new PlSymbol(sym.Label, sym.Value, width, plsSource, plsType, tag,
-                plSymbols.Add(new PlSymbol(sym.Label, sym.Value, width, plsSource, plsType, tag));
+                    offset));
             }
 
             return plSymbols;