When retrieving an ElementRegion, if its super region is a StringRegion,
retrieve the string value.
git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@71430 91177308-0d34-0410-b5e6-96231b3b80d8
diff --git a/lib/Analysis/RegionStore.cpp b/lib/Analysis/RegionStore.cpp
index 84c8195..9d29a90 100644
--- a/lib/Analysis/RegionStore.cpp
+++ b/lib/Analysis/RegionStore.cpp
@@ -736,6 +736,24 @@
if (state.contains<RegionKills>(R))
return UnknownVal();
+ // Check if the region is an element region of a string literal.
+ if (const ElementRegion *ER = dyn_cast<ElementRegion>(R)) {
+ if (const StringRegion *StrR=dyn_cast<StringRegion>(ER->getSuperRegion())) {
+ const StringLiteral *Str = StrR->getStringLiteral();
+ SVal Idx = ER->getIndex();
+ if (nonloc::ConcreteInt *CI = dyn_cast<nonloc::ConcreteInt>(&Idx)) {
+ int64_t i = CI->getValue().getSExtValue();
+ char c;
+ if (i == Str->getByteLength())
+ c = '\0';
+ else
+ c = Str->getStrData()[i];
+ const llvm::APSInt &V = getBasicVals().getValue(c, getContext().CharTy);
+ return nonloc::ConcreteInt(V);
+ }
+ }
+ }
+
// If the region is an element or field, it may have a default value.
if (isa<ElementRegion>(R) || isa<FieldRegion>(R)) {
const MemRegion* SuperR = cast<SubRegion>(R)->getSuperRegion();