[clang][bytecode] Support ImplicitValueInitExpr for multi-dim arrays

clang/lib/AST/ByteCode/Compiler.cpp

@@ -1642,22 +1642,8 @@ bool Compiler<Emitter>::VisitImplicitValueInitExpr(
   if (QT->isIncompleteArrayType())
     return true;
 
-  if (QT->isArrayType()) {
-    const ArrayType *AT = QT->getAsArrayTypeUnsafe();
-    assert(AT);
-    const auto *CAT = cast<ConstantArrayType>(AT);
-    size_t NumElems = CAT->getZExtSize();
-    PrimType ElemT = classifyPrim(CAT->getElementType());
-
-    for (size_t I = 0; I != NumElems; ++I) {
-      if (!this->visitZeroInitializer(ElemT, CAT->getElementType(), E))
-        return false;
-      if (!this->emitInitElem(ElemT, I, E))
-        return false;
-    }
-
-    return true;
-  }
+  if (QT->isArrayType())
+    return this->visitZeroArrayInitializer(QT, E);
 
   if (const auto *ComplexTy = E->getType()->getAs<ComplexType>()) {
     assert(Initializing);
@@ -3916,18 +3902,9 @@ bool Compiler<Emitter>::visitZeroRecordInitializer(const Record *R,
           return false;
       }
     } else if (D->isCompositeArray()) {
-      const Record *ElemRecord = D->ElemDesc->ElemRecord;
-      assert(D->ElemDesc->ElemRecord);
-      for (uint32_t I = 0, N = D->getNumElems(); I != N; ++I) {
-        if (!this->emitConstUint32(I, E))
-          return false;
-        if (!this->emitArrayElemPtr(PT_Uint32, E))
-          return false;
-        if (!this->visitZeroRecordInitializer(ElemRecord, E))
-          return false;
-        if (!this->emitPopPtr(E))
-          return false;
-      }
+      // Can't be a vector or complex field.
+      if (!this->visitZeroArrayInitializer(D->getType(), E))
+        return false;
     } else if (D->isRecord()) {
       if (!this->visitZeroRecordInitializer(D->ElemRecord, E))
         return false;
@@ -3958,6 +3935,52 @@ bool Compiler<Emitter>::visitZeroRecordInitializer(const Record *R,
   return true;
 }
 
+template <class Emitter>
+bool Compiler<Emitter>::visitZeroArrayInitializer(QualType T, const Expr *E) {
+  assert(T->isArrayType() || T->isAnyComplexType() || T->isVectorType());
+  const ArrayType *AT = T->getAsArrayTypeUnsafe();
+  QualType ElemType = AT->getElementType();
+  size_t NumElems = cast<ConstantArrayType>(AT)->getZExtSize();
+
+  if (std::optional<PrimType> ElemT = classify(ElemType)) {
+    for (size_t I = 0; I != NumElems; ++I) {
+      if (!this->visitZeroInitializer(*ElemT, ElemType, E))
+        return false;
+      if (!this->emitInitElem(*ElemT, I, E))
+        return false;
+    }
+    return true;
+  } else if (ElemType->isRecordType()) {
+    const Record *R = getRecord(ElemType);
+
+    for (size_t I = 0; I != NumElems; ++I) {
+      if (!this->emitConstUint32(I, E))
+        return false;
+      if (!this->emitArrayElemPtr(PT_Uint32, E))
+        return false;
+      if (!this->visitZeroRecordInitializer(R, E))
+        return false;
+      if (!this->emitPopPtr(E))
+        return false;
+    }
+    return true;
+  } else if (ElemType->isArrayType()) {
+    for (size_t I = 0; I != NumElems; ++I) {
+      if (!this->emitConstUint32(I, E))
+        return false;
+      if (!this->emitArrayElemPtr(PT_Uint32, E))
+        return false;
+      if (!this->visitZeroArrayInitializer(ElemType, E))
+        return false;
+      if (!this->emitPopPtr(E))
+        return false;
+    }
+    return true;
+  }
+
+  return false;
+}
+
 template <class Emitter>
 template <typename T>
 bool Compiler<Emitter>::emitConst(T Value, PrimType Ty, const Expr *E) {

clang/lib/AST/ByteCode/Compiler.h

@@ -325,6 +325,7 @@ class Compiler : public ConstStmtVisitor<Compiler<Emitter>, bool>,
   /// Emits a zero initializer.
   bool visitZeroInitializer(PrimType T, QualType QT, const Expr *E);
   bool visitZeroRecordInitializer(const Record *R, const Expr *E);
+  bool visitZeroArrayInitializer(QualType T, const Expr *E);
 
   /// Emits an APSInt constant.
   bool emitConst(const llvm::APSInt &Value, PrimType Ty, const Expr *E);

clang/lib/AST/ByteCode/InterpFrame.cpp

@@ -234,7 +234,12 @@ SourceInfo InterpFrame::getSource(CodePtr PC) const {
   if (Func && !funcHasUsableBody(Func) && Caller)
     return Caller->getSource(RetPC);
 
-  return S.getSource(Func, PC);
+  // Similarly, if the resulting source location is invalid anyway,
+  // point to the caller instead.
+  SourceInfo Result = S.getSource(Func, PC);
+  if (Result.getLoc().isInvalid() && Caller)
+    return Caller->getSource(RetPC);
+  return Result;
 }
 
 const Expr *InterpFrame::getExpr(CodePtr PC) const {

clang/test/AST/ByteCode/placement-new.cpp

@@ -1,4 +1,4 @@
-// RUN: %clang_cc1 -std=c++2c -fcxx-exceptions -fexperimental-new-constant-interpreter -verify=expected,both %s
+// RUN: %clang_cc1 -std=c++2c -fcxx-exceptions -fexperimental-new-constant-interpreter -verify=expected,both %s -DBYTECODE
 // RUN: %clang_cc1 -std=c++2c -fcxx-exceptions -verify=ref,both %s
 
 namespace std {
@@ -338,3 +338,17 @@ namespace PR48606 {
   }
   static_assert(f());
 }
+
+#ifdef BYTECODE
+constexpr int N = [] // expected-error {{must be initialized by a constant expression}} \
+                     // expected-note {{assignment to dereferenced one-past-the-end pointer is not allowed in a constant expression}} \
+                     // expected-note {{in call to}}
+{
+    struct S {
+        int a[1];
+    };
+    S s;
+    ::new (s.a) int[1][2][3][4]();
+    return s.a[0];
+}();
+#endif