1 files changed, 64 insertions, 3 deletions

diff --git a/contrib/llvm-project/clang/lib/AST/Interp/Context.cpp b/contrib/llvm-project/clang/lib/AST/Interp/Context.cpp
index 16471242f328..eeb7fa9379f5 100644
--- a/contrib/llvm-project/clang/lib/AST/Interp/Context.cpp
+++ b/contrib/llvm-project/clang/lib/AST/Interp/Context.cpp
@@ -42,6 +42,11 @@ bool Context::isPotentialConstantExpr(State &Parent, const FunctionDecl *FD) {
     }
   }
 
+  APValue DummyResult;
+  if (!Run(Parent, Func, DummyResult)) {
+    return false;
+  }
+
   return Func->isConstexpr();
 }
 
@@ -50,6 +55,11 @@ bool Context::evaluateAsRValue(State &Parent, const Expr *E, APValue &Result) {
   ByteCodeExprGen<EvalEmitter> C(*this, *P, Parent, Stk, Result);
   if (Check(Parent, C.interpretExpr(E))) {
     assert(Stk.empty());
+#ifndef NDEBUG
+    // Make sure we don't rely on some value being still alive in
+    // InterpStack memory.
+    Stk.clear();
+#endif
     return true;
   }
 
@@ -63,6 +73,11 @@ bool Context::evaluateAsInitializer(State &Parent, const VarDecl *VD,
   ByteCodeExprGen<EvalEmitter> C(*this, *P, Parent, Stk, Result);
   if (Check(Parent, C.interpretDecl(VD))) {
     assert(Stk.empty());
+#ifndef NDEBUG
+    // Make sure we don't rely on some value being still alive in
+    // InterpStack memory.
+    Stk.clear();
+#endif
     return true;
   }
 
@@ -73,9 +88,11 @@ bool Context::evaluateAsInitializer(State &Parent, const VarDecl *VD,
 const LangOptions &Context::getLangOpts() const { return Ctx.getLangOpts(); }
 
 std::optional<PrimType> Context::classify(QualType T) const {
-  if (T->isReferenceType() || T->isPointerType()) {
+  if (T->isFunctionPointerType() || T->isFunctionReferenceType())
+    return PT_FnPtr;
+
+  if (T->isReferenceType() || T->isPointerType())
     return PT_Ptr;
-  }
 
   if (T->isBooleanType())
     return PT_Bool;
@@ -113,6 +130,9 @@ std::optional<PrimType> Context::classify(QualType T) const {
   if (T->isNullPtrType())
     return PT_Ptr;
 
+  if (T->isFloatingType())
+    return PT_Float;
+
   if (auto *AT = dyn_cast<AtomicType>(T))
     return classify(AT->getValueType());
 
@@ -123,7 +143,13 @@ unsigned Context::getCharBit() const {
   return Ctx.getTargetInfo().getCharWidth();
 }
 
-bool Context::Run(State &Parent, Function *Func, APValue &Result) {
+/// Simple wrapper around getFloatTypeSemantics() to make code a
+/// little shorter.
+const llvm::fltSemantics &Context::getFloatSemantics(QualType T) const {
+  return Ctx.getFloatTypeSemantics(T);
+}
+
+bool Context::Run(State &Parent, const Function *Func, APValue &Result) {
   InterpState State(Parent, *P, Stk, *this);
   State.Current = new InterpFrame(State, Func, /*Caller=*/nullptr, {});
   if (Interpret(State, Result))
@@ -142,3 +168,38 @@ bool Context::Check(State &Parent, llvm::Expected<bool> &&Flag) {
   });
   return false;
 }
+
+// TODO: Virtual bases?
+const CXXMethodDecl *
+Context::getOverridingFunction(const CXXRecordDecl *DynamicDecl,
+                               const CXXRecordDecl *StaticDecl,
+                               const CXXMethodDecl *InitialFunction) const {
+
+  const CXXRecordDecl *CurRecord = DynamicDecl;
+  const CXXMethodDecl *FoundFunction = InitialFunction;
+  for (;;) {
+    const CXXMethodDecl *Overrider =
+        FoundFunction->getCorrespondingMethodDeclaredInClass(CurRecord, false);
+    if (Overrider)
+      return Overrider;
+
+    // Common case of only one base class.
+    if (CurRecord->getNumBases() == 1) {
+      CurRecord = CurRecord->bases_begin()->getType()->getAsCXXRecordDecl();
+      continue;
+    }
+
+    // Otherwise, go to the base class that will lead to the StaticDecl.
+    for (const CXXBaseSpecifier &Spec : CurRecord->bases()) {
+      const CXXRecordDecl *Base = Spec.getType()->getAsCXXRecordDecl();
+      if (Base == StaticDecl || Base->isDerivedFrom(StaticDecl)) {
+        CurRecord = Base;
+        break;
+      }
+    }
+  }
+
+  llvm_unreachable(
+      "Couldn't find an overriding function in the class hierarchy?");
+  return nullptr;
+}