Fix analyzer regression reported in PR 4164:
- Update the old StoreManager::CastRegion to strip off 'ElementRegions' when
casting to void* (Zhongxing: please validate)
- Pass-by-reference argument invalidation logic in CFRefCount.cpp:
- Strip ElementRegions when the ElementRegion is just a 'raw data' view
on top of the underlying typed region.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@71094 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/CFRefCount.cpp b/lib/Analysis/CFRefCount.cpp
index ca42000..4c517fd 100644
--- a/lib/Analysis/CFRefCount.cpp
+++ b/lib/Analysis/CFRefCount.cpp
@@ -2606,7 +2606,29 @@
const TypedRegion* R = dyn_cast<TypedRegion>(MR->getRegion());
- if (R) {
+ if (R) {
+ // Are we dealing with an ElementRegion? If the element type is
+ // a basic integer type (e.g., char, int) and the underying region
+ // is also typed then strip off the ElementRegion.
+ // FIXME: We really need to think about this for the general case
+ // as sometimes we are reasoning about arrays and other times
+ // about (char*), etc., is just a form of passing raw bytes.
+ // e.g., void *p = alloca(); foo((char*)p);
+ if (const ElementRegion *ER = dyn_cast<ElementRegion>(R)) {
+ // Checking for 'integral type' is probably too promiscuous, but
+ // we'll leave it in for now until we have a systematic way of
+ // handling all of these cases. Eventually we need to come up
+ // with an interface to StoreManager so that this logic can be
+ // approriately delegated to the respective StoreManagers while
+ // still allowing us to do checker-specific logic (e.g.,
+ // invalidating reference counts), probably via callbacks.
+ if (ER->getElementType()->isIntegralType())
+ if (const TypedRegion *superReg =
+ dyn_cast<TypedRegion>(ER->getSuperRegion()))
+ R = superReg;
+ // FIXME: What about layers of ElementRegions?
+ }
+
// Is the invalidated variable something that we were tracking?
SymbolRef Sym = state.GetSValAsScalarOrLoc(R).getAsLocSymbol();
diff --git a/lib/Analysis/Store.cpp b/lib/Analysis/Store.cpp
index 32b186b..49411b4 100644
--- a/lib/Analysis/Store.cpp
+++ b/lib/Analysis/Store.cpp
@@ -44,18 +44,37 @@
QualType Pointee = PTy->getPointeeType();
if (Pointee->isVoidType()) {
- // Casts to void* only removes TypedViewRegion. If there is no
- // TypedViewRegion, leave the region untouched. This happens when:
- //
- // void foo(void*);
- // ...
- // void bar() {
- // int x;
- // foo(&x);
- // }
-
- if (const TypedViewRegion *TR = dyn_cast<TypedViewRegion>(R))
- R = TR->removeViews();
+ do {
+ if (const TypedViewRegion *TR = dyn_cast<TypedViewRegion>(R)) {
+ // Casts to void* removes TypedViewRegion. This happens when:
+ //
+ // void foo(void*);
+ // ...
+ // void bar() {
+ // int x;
+ // foo(&x);
+ // }
+ //
+ R = TR->removeViews();
+ continue;
+ }
+ else if (const ElementRegion *ER = dyn_cast<ElementRegion>(R)) {
+ // Casts to void* also removes ElementRegions. This happens when:
+ //
+ // void foo(void*);
+ // ...
+ // void bar() {
+ // int x;
+ // foo((char*)&x);
+ // }
+ //
+ R = ER->getSuperRegion();
+ continue;
+ }
+ else
+ break;
+ }
+ while (0);
return CastResult(state, R);
}