SymbolReaper::isLive(SymbolRef) now always returns true for SymbolRegionRvalues because these represent the symbolic values for parameters/globals upon entry to the function. These values are always ;live' because they represent constraints on the context of how the function was called. This will be useful for both summary generation but is also necessary to get RegionStore's lazy-binding of locations to symbols to work in practice with RemoveDeadBindings.

llvm-svn: 62771

clang/lib/Analysis/SymbolManager.cpp

@@ -92,6 +92,11 @@ bool SymbolReaper::maybeDead(SymbolRef sym) {
 }
 
 bool SymbolReaper::isLive(SymbolRef sym) {
-  return TheLiving.contains(sym);
+  if (TheLiving.contains(sym))
+    return true;
+  
+  // Interogate the symbol.  It may derive from an input value to
+  // the analyzed function/method.
+  return isa<SymbolRegionRValue>(SymMgr.getSymbolData(sym));
 }