[clang] [clang][Interp] Implement dynamic memory allocation handling (PR #70306)

[Timm Baeder via cfe-commits]

================
@@ -2544,6 +2544,85 @@ bool ByteCodeExprGen<Emitter>::VisitCXXInheritedCtorInitExpr(
   return this->emitCall(F, 0, E);
 }
 
+template <class Emitter>
+bool ByteCodeExprGen<Emitter>::VisitCXXNewExpr(const CXXNewExpr *E) {
+  assert(classifyPrim(E->getType()) == PT_Ptr);
+  const Expr *Init = E->getInitializer();
+  QualType ElementType = E->getAllocatedType();
+  std::optional<PrimType> ElemT = classify(ElementType);
+
+  const Descriptor *Desc;
+  if (ElemT) {
+    if (E->isArray())
+      Desc = nullptr; // We're not going to use it in this case.
+    else
+      Desc = P.createDescriptor(E, *ElemT, Descriptor::InlineDescMD,
+                                /*IsConst=*/false, /*IsTemporary=*/false,
+                                /*IsMutable=*/false);
+  } else {
+    Desc = P.createDescriptor(
+        E, ElementType.getTypePtr(),
+        E->isArray() ? std::nullopt : Descriptor::InlineDescMD,
+        /*IsConst=*/false, /*IsTemporary=*/false, /*IsMutable=*/false, Init);
+  }
+
+  if (E->isArray()) {
+    std::optional<const Expr *> ArraySizeExpr = E->getArraySize();
+    if (!ArraySizeExpr)
+      return false;
+    assert(ArraySizeExpr);
+    PrimType SizeT = classifyPrim((*ArraySizeExpr)->getType());
+
+    if (!this->visit(*ArraySizeExpr))
+      return false;
+
+    if (ElemT) {
+      // N primitive elements.
+      if (!this->emitAllocN(SizeT, *ElemT, E, E))
+        return false;
+    } else {
+      // N Composite elements.
+      if (!this->emitAllocCN(SizeT, Desc, E))
+        return false;
+    }
+
----------------
tbaederr wrote:

Good catch

https://github.com/llvm/llvm-project/pull/70306