ImDebugger: fix stale symbol list after a game is reloaded

The disasm window cached the flattened symbol list and only rebuilt it when one
of three menu items said so. Nothing marked it dirty when a game booted or
exited, and a new SymbolMap is allocated per boot, so the list kept showing the
previous game's functions.

Give SymbolMap a version counter that every mutator bumps, and let the window
compare against it instead. The counter is process-wide rather than per-map, so
a fresh map can't hand out a version a cached copy already holds.

Also re-find the selected symbol by address after a rebuild (the index means
something else afterwards), and drop the unused symbol cache members in
ImMemWindow.

Co-Authored-By: Claude Opus 5 (1M context) <noreply@anthropic.com>
Claude-Session: https://claude.ai/code/session_01SfY7iFJEjmRXf1XGrTs4MF

Core/Debugger/SymbolMap.cpp

@@ -50,11 +50,24 @@
 
 SymbolMap *g_symbolMap;
 
+// Not per-instance, so that versions from a map that's been thrown away (one is created and
+// destroyed per game boot) can't collide with the current one's. See SymbolMap::Version.
+static uint32_t g_symbolMapVersionCounter;
+
+SymbolMap::SymbolMap() {
+	Bump();
+}
+
+void SymbolMap::Bump() {
+	version_ = ++g_symbolMapVersionCounter;
+}
+
 void SymbolMap::SortSymbols() {
 	AssignFunctionIndices();
 }
 
 void SymbolMap::Clear() {
+	Bump();
 	functions.clear();
 	labels.clear();
 	data.clear();
@@ -768,6 +781,8 @@ std::vector<SymbolEntry> SymbolMap::GetAllActiveSymbols(SymbolType symbolMask) {
 }
 
 void SymbolMap::AddModule(const char *name, u32 address, u32 size, u32 crc) {
+	Bump();
+
 	for (auto &module : modules) {
 		if (equals(module.name, name)) {
 			// A name match alone isn't proof it's really the same module reloading - some
@@ -803,6 +818,7 @@ void SymbolMap::AddModule(const char *name, u32 address, u32 size, u32 crc) {
 }
 
 void SymbolMap::UnloadModule(u32 address, u32 size) {
+	Bump();
 	activeModuleEnds.erase(address + size);
 	activeNeedUpdate_ = true;
 }
@@ -907,6 +923,8 @@ std::vector<LoadedModuleInfo> SymbolMap::getAllModules() const {
 }
 
 void SymbolMap::AddFunction(const char* name, u32 address, u32 size, int moduleIndex, bool updateName) {
+	Bump();
+
 	moduleIndex = ResolveModuleIndex(address, moduleIndex);
 
 	// Is there an existing one?
@@ -1116,6 +1134,8 @@ void SymbolMap::UpdateActiveSymbols() {
 }
 
 bool SymbolMap::SetFunctionSize(u32 startAddress, u32 newSize) {
+	Bump();
+
 	if (activeNeedUpdate_)
 		UpdateActiveSymbols();
 
@@ -1136,6 +1156,8 @@ bool SymbolMap::SetFunctionSize(u32 startAddress, u32 newSize) {
 }
 
 bool SymbolMap::RemoveFunction(u32 startAddress, bool removeName) {
+	Bump();
+
 	if (activeNeedUpdate_)
 		UpdateActiveSymbols();
 
@@ -1167,6 +1189,8 @@ bool SymbolMap::RemoveFunction(u32 startAddress, bool removeName) {
 }
 
 void SymbolMap::AddLabel(const char* name, u32 address, int moduleIndex, bool updateName) {
+	Bump();
+
 	moduleIndex = ResolveModuleIndex(address, moduleIndex);
 
 	// Is there an existing one?
@@ -1225,6 +1249,8 @@ void SymbolMap::AddLabel(const char* name, u32 address, int moduleIndex, bool up
 }
 
 void SymbolMap::SetLabelName(const char* name, u32 address) {
+	Bump();
+
 	if (activeNeedUpdate_)
 		UpdateActiveSymbols();
 
@@ -1289,6 +1315,8 @@ bool SymbolMap::GetLabelValue(const char* name, u32& dest) {
 }
 
 void SymbolMap::AddData(u32 address, u32 size, DataType type, int moduleIndex) {
+	Bump();
+
 	moduleIndex = ResolveModuleIndex(address, moduleIndex);
 
 	// Is there an existing one?
@@ -1395,6 +1423,8 @@ DataType SymbolMap::GetDataType(u32 startAddress) {
 }
 
 bool SymbolMap::RemoveData(u32 startAddress, bool removeName) {
+	Bump();
+
 	if (activeNeedUpdate_)
 		UpdateActiveSymbols();