[Analyzer] Support bodyfarming libstdc++ implementation of std::call_once.
Differential Revision: https://reviews.llvm.org/D38810
llvm-svn: 315508
diff --git a/clang/lib/Analysis/BodyFarm.cpp b/clang/lib/Analysis/BodyFarm.cpp
index 81ad999..ae89350 100644
--- a/clang/lib/Analysis/BodyFarm.cpp
+++ b/clang/lib/Analysis/BodyFarm.cpp
@@ -108,7 +108,7 @@
/// Returns a *first* member field of a record declaration with a given name.
/// \return an nullptr if no member with such a name exists.
- NamedDecl *findMemberField(const CXXRecordDecl *RD, StringRef Name);
+ ValueDecl *findMemberField(const RecordDecl *RD, StringRef Name);
private:
ASTContext &C;
@@ -234,7 +234,7 @@
OK_Ordinary);
}
-NamedDecl *ASTMaker::findMemberField(const CXXRecordDecl *RD, StringRef Name) {
+ValueDecl *ASTMaker::findMemberField(const RecordDecl *RD, StringRef Name) {
CXXBasePaths Paths(
/* FindAmbiguities=*/false,
@@ -246,7 +246,7 @@
DeclContextLookupResult Decls = RD->lookup(DeclName);
for (NamedDecl *FoundDecl : Decls)
if (!FoundDecl->getDeclContext()->isFunctionOrMethod())
- return FoundDecl;
+ return cast<ValueDecl>(FoundDecl);
return nullptr;
}
@@ -328,25 +328,31 @@
const ParmVarDecl *Callback = D->getParamDecl(1);
QualType CallbackType = Callback->getType().getNonReferenceType();
QualType FlagType = Flag->getType().getNonReferenceType();
- CXXRecordDecl *FlagCXXDecl = FlagType->getAsCXXRecordDecl();
- if (!FlagCXXDecl) {
- DEBUG(llvm::dbgs() << "Flag field is not a CXX record: "
- << "unknown std::call_once implementation."
- << "Ignoring the call.\n");
+ auto *FlagRecordDecl = dyn_cast_or_null<RecordDecl>(FlagType->getAsTagDecl());
+
+ if (!FlagRecordDecl) {
+ DEBUG(llvm::dbgs() << "Flag field is not a record: "
+ << "unknown std::call_once implementation, "
+ << "ignoring the call.\n");
return nullptr;
}
- // Note: here we are assuming libc++ implementation of call_once,
- // which has a struct with a field `__state_`.
- // Body farming might not work for other `call_once` implementations.
- NamedDecl *FoundDecl = M.findMemberField(FlagCXXDecl, "__state_");
- ValueDecl *FieldDecl;
- if (FoundDecl) {
- FieldDecl = dyn_cast<ValueDecl>(FoundDecl);
- } else {
+ // We initially assume libc++ implementation of call_once,
+ // where the once_flag struct has a field `__state_`.
+ ValueDecl *FlagFieldDecl = M.findMemberField(FlagRecordDecl, "__state_");
+
+ // Otherwise, try libstdc++ implementation, with a field
+ // `_M_once`
+ if (!FlagFieldDecl) {
DEBUG(llvm::dbgs() << "No field __state_ found on std::once_flag struct, "
- << "unable to synthesize call_once body, ignoring "
- << "the call.\n");
+ << "assuming libstdc++ implementation\n");
+ FlagFieldDecl = M.findMemberField(FlagRecordDecl, "_M_once");
+ }
+
+ if (!FlagFieldDecl) {
+ DEBUG(llvm::dbgs() << "No field _M_once found on std::once flag struct: "
+ << "unknown std::call_once implementation, "
+ << "ignoring the call");
return nullptr;
}
@@ -383,7 +389,7 @@
/* GetNonReferenceType=*/true);
- MemberExpr *Deref = M.makeMemberExpression(FlagDecl, FieldDecl);
+ MemberExpr *Deref = M.makeMemberExpression(FlagDecl, FlagFieldDecl);
assert(Deref->isLValue());
QualType DerefType = Deref->getType();