Add optional record of "location" SVals in the environment. When we analyzing loads/stores, we lose the location SVal, which makes it difficult to recover in some cases (e.g., for post diagnostics). This is prep for pending changes to GRExprEngine.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@112930 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Checker/Environment.cpp b/lib/Checker/Environment.cpp
index 48152ce..02291f4 100644
--- a/lib/Checker/Environment.cpp
+++ b/lib/Checker/Environment.cpp
@@ -80,7 +80,7 @@
return LookupExpr(E);
}
-Environment EnvironmentManager::BindExpr(Environment Env, const Stmt *S,
+Environment EnvironmentManager::bindExpr(Environment Env, const Stmt *S,
SVal V, bool Invalidate) {
assert(S);
@@ -94,6 +94,16 @@
return Environment(F.Add(Env.ExprBindings, S, V));
}
+static inline const Stmt *MakeLocation(const Stmt *S) {
+ return (const Stmt*) (((uintptr_t) S) | 0x1);
+}
+
+Environment EnvironmentManager::bindExprAndLocation(Environment Env,
+ const Stmt *S,
+ SVal location, SVal V) {
+ return Environment(F.Add(F.Add(Env.ExprBindings, MakeLocation(S), V), S, V));
+}
+
namespace {
class MarkLiveCallback : public SymbolVisitor {
SymbolReaper &SymReaper;
@@ -115,6 +125,12 @@
return false;
}
+// In addition to mapping from Stmt * - > SVals in the Environment, we also
+// maintain a mapping from Stmt * -> SVals (locations) that were used during
+// a load and store.
+static inline bool IsLocation(const Stmt *S) {
+ return (bool) (((uintptr_t) S) & 0x1);
+}
// RemoveDeadBindings:
// - Remove subexpression bindings.
@@ -123,7 +139,6 @@
// - Mark their reachable symbols live in SymbolReaper,
// see ScanReachableSymbols.
// - Mark the region in DRoots if the binding is a loc::MemRegionVal.
-
Environment
EnvironmentManager::RemoveDeadBindings(Environment Env,
SymbolReaper &SymReaper,
@@ -136,12 +151,25 @@
// individually removing all the subexpression bindings (which will greatly
// outnumber block-level expression bindings).
Environment NewEnv = getInitialEnvironment();
+
+ llvm::SmallVector<std::pair<const Stmt*, SVal>, 10> deferredLocations;
// Iterate over the block-expr bindings.
for (Environment::iterator I = Env.begin(), E = Env.end();
I != E; ++I) {
const Stmt *BlkExpr = I.getKey();
+
+ // For recorded locations (used when evaluating loads and stores), we
+ // consider them live only when their associated normal expression is
+ // also live.
+ // NOTE: This assumes that loads/stores that evaluated to UnknownVal
+ // still have an entry in the map.
+ if (IsLocation(BlkExpr)) {
+ deferredLocations.push_back(std::make_pair(BlkExpr, I.getData()));
+ continue;
+ }
+
const SVal &X = I.getData();
// Block-level expressions in callers are assumed always live.
@@ -186,6 +214,15 @@
if (X.isUndef() && cast<UndefinedVal>(X).getData())
NewEnv.ExprBindings = F.Add(NewEnv.ExprBindings, BlkExpr, X);
}
+
+ // Go through he deferred locations and add them to the new environment if
+ // the correspond Stmt* is in the map as well.
+ for (llvm::SmallVectorImpl<std::pair<const Stmt*, SVal> >::iterator
+ I = deferredLocations.begin(), E = deferredLocations.end(); I != E; ++I) {
+ const Stmt *S = (Stmt*) (((uintptr_t) I->first) & (uintptr_t) ~0x1);
+ if (NewEnv.ExprBindings.lookup(S))
+ NewEnv.ExprBindings = F.Add(NewEnv.ExprBindings, I->first, I->second);
+ }
return NewEnv;
}