diff --git a/lldb/source/Plugins/Language/CPlusPlus/LibCxx.cpp b/lldb/source/Plugins/Language/CPlusPlus/LibCxx.cpp
@@ -231,21 +231,22 @@ lldb_private::formatters::LibCxxMapIteratorSyntheticFrontEnd::
     Update();
 }
 
-bool lldb_private::formatters::LibCxxMapIteratorSyntheticFrontEnd::Update() {
+lldb::ChildCacheState
+lldb_private::formatters::LibCxxMapIteratorSyntheticFrontEnd::Update() {
   m_pair_sp.reset();
   m_pair_ptr = nullptr;
 
   ValueObjectSP valobj_sp = m_backend.GetSP();
   if (!valobj_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
   TargetSP target_sp(valobj_sp->GetTargetSP());
 
   if (!target_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
   if (!valobj_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
   // this must be a ValueObject* because it is a child of the ValueObject we
   // are producing children for it if were a ValueObjectSP, we would end up
@@ -278,7 +279,7 @@ bool lldb_private::formatters::LibCxxMapIteratorSyntheticFrontEnd::Update() {
       auto __i_(valobj_sp->GetChildMemberWithName("__i_"));
       if (!__i_) {
         m_pair_ptr = nullptr;
-        return false;
+        return lldb::ChildCacheState::eRefetch;
       }
       CompilerType pair_type(
           __i_->GetCompilerType().GetTypeTemplateArgument(0));
@@ -290,7 +291,7 @@ bool lldb_private::formatters::LibCxxMapIteratorSyntheticFrontEnd::Update() {
           0, name, &bit_offset_ptr, &bitfield_bit_size_ptr, &is_bitfield_ptr);
       if (!pair_type) {
         m_pair_ptr = nullptr;
-        return false;
+        return lldb::ChildCacheState::eRefetch;
       }
 
       auto addr(m_pair_ptr->GetValueAsUnsigned(LLDB_INVALID_ADDRESS));
@@ -299,7 +300,7 @@ bool lldb_private::formatters::LibCxxMapIteratorSyntheticFrontEnd::Update() {
         auto ts = pair_type.GetTypeSystem();
         auto ast_ctx = ts.dyn_cast_or_null<TypeSystemClang>();
         if (!ast_ctx)
-          return false;
+          return lldb::ChildCacheState::eRefetch;
 
         // Mimick layout of std::__tree_iterator::__ptr_ and read it in
         // from process memory.
@@ -328,14 +329,14 @@ bool lldb_private::formatters::LibCxxMapIteratorSyntheticFrontEnd::Update() {
              {"payload", pair_type}});
         std::optional<uint64_t> size = tree_node_type.GetByteSize(nullptr);
         if (!size)
-          return false;
+          return lldb::ChildCacheState::eRefetch;
         WritableDataBufferSP buffer_sp(new DataBufferHeap(*size, 0));
         ProcessSP process_sp(target_sp->GetProcessSP());
         Status error;
         process_sp->ReadMemory(addr, buffer_sp->GetBytes(),
                                buffer_sp->GetByteSize(), error);
         if (error.Fail())
-          return false;
+          return lldb::ChildCacheState::eRefetch;
         DataExtractor extractor(buffer_sp, process_sp->GetByteOrder(),
                                 process_sp->GetAddressByteSize());
         auto pair_sp = CreateValueObjectFromData(
@@ -347,7 +348,7 @@ bool lldb_private::formatters::LibCxxMapIteratorSyntheticFrontEnd::Update() {
     }
   }
 
-  return false;
+  return lldb::ChildCacheState::eRefetch;
 }
 
 size_t lldb_private::formatters::LibCxxMapIteratorSyntheticFrontEnd::
@@ -399,22 +400,22 @@ lldb_private::formatters::LibCxxUnorderedMapIteratorSyntheticFrontEnd::
     Update();
 }
 
-bool lldb_private::formatters::LibCxxUnorderedMapIteratorSyntheticFrontEnd::
-    Update() {
+lldb::ChildCacheState lldb_private::formatters::
+    LibCxxUnorderedMapIteratorSyntheticFrontEnd::Update() {
   m_pair_sp.reset();
   m_iter_ptr = nullptr;
 
   ValueObjectSP valobj_sp = m_backend.GetSP();
   if (!valobj_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
   TargetSP target_sp(valobj_sp->GetTargetSP());
 
   if (!target_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
   if (!valobj_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
   auto exprPathOptions = ValueObject::GetValueForExpressionPathOptions()
                              .DontCheckDotVsArrowSyntax()
@@ -437,7 +438,7 @@ bool lldb_private::formatters::LibCxxUnorderedMapIteratorSyntheticFrontEnd::
     auto iter_child(valobj_sp->GetChildMemberWithName("__i_"));
     if (!iter_child) {
       m_iter_ptr = nullptr;
-      return false;
+      return lldb::ChildCacheState::eRefetch;
     }
 
     CompilerType node_type(iter_child->GetCompilerType()
@@ -455,19 +456,19 @@ bool lldb_private::formatters::LibCxxUnorderedMapIteratorSyntheticFrontEnd::
         0, name, &bit_offset_ptr, &bitfield_bit_size_ptr, &is_bitfield_ptr);
     if (!pair_type) {
       m_iter_ptr = nullptr;
-      return false;
+      return lldb::ChildCacheState::eRefetch;
     }
 
     uint64_t addr = m_iter_ptr->GetValueAsUnsigned(LLDB_INVALID_ADDRESS);
     m_iter_ptr = nullptr;
 
     if (addr == 0 || addr == LLDB_INVALID_ADDRESS)
-      return false;
+      return lldb::ChildCacheState::eRefetch;
 
     auto ts = pair_type.GetTypeSystem();
     auto ast_ctx = ts.dyn_cast_or_null<TypeSystemClang>();
     if (!ast_ctx)
-      return false;
+      return lldb::ChildCacheState::eRefetch;
 
     // Mimick layout of std::__hash_iterator::__node_ and read it in
     // from process memory.
@@ -489,14 +490,14 @@ bool lldb_private::formatters::LibCxxUnorderedMapIteratorSyntheticFrontEnd::
          {"__value_", pair_type}});
     std::optional<uint64_t> size = tree_node_type.GetByteSize(nullptr);
     if (!size)
-      return false;
+      return lldb::ChildCacheState::eRefetch;
     WritableDataBufferSP buffer_sp(new DataBufferHeap(*size, 0));
     ProcessSP process_sp(target_sp->GetProcessSP());
     Status error;
     process_sp->ReadMemory(addr, buffer_sp->GetBytes(),
                            buffer_sp->GetByteSize(), error);
     if (error.Fail())
-      return false;
+      return lldb::ChildCacheState::eRefetch;
     DataExtractor extractor(buffer_sp, process_sp->GetByteOrder(),
                             process_sp->GetAddressByteSize());
     auto pair_sp = CreateValueObjectFromData(
@@ -505,7 +506,7 @@ bool lldb_private::formatters::LibCxxUnorderedMapIteratorSyntheticFrontEnd::
       m_pair_sp = pair_sp->GetChildAtIndex(2);
   }
 
-  return false;
+  return lldb::ChildCacheState::eRefetch;
 }
 
 size_t lldb_private::formatters::LibCxxUnorderedMapIteratorSyntheticFrontEnd::
@@ -600,22 +601,23 @@ lldb_private::formatters::LibcxxSharedPtrSyntheticFrontEnd::GetChildAtIndex(
   return lldb::ValueObjectSP();
 }
 
-bool lldb_private::formatters::LibcxxSharedPtrSyntheticFrontEnd::Update() {
+lldb::ChildCacheState
+lldb_private::formatters::LibcxxSharedPtrSyntheticFrontEnd::Update() {
   m_cntrl = nullptr;
 
   ValueObjectSP valobj_sp = m_backend.GetSP();
   if (!valobj_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
   TargetSP target_sp(valobj_sp->GetTargetSP());
   if (!target_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
   lldb::ValueObjectSP cntrl_sp(valobj_sp->GetChildMemberWithName("__cntrl_"));
 
   m_cntrl = cntrl_sp.get(); // need to store the raw pointer to avoid a circular
                             // dependency
-  return false;
+  return lldb::ChildCacheState::eRefetch;
 }
 
 bool lldb_private::formatters::LibcxxSharedPtrSyntheticFrontEnd::
@@ -689,14 +691,15 @@ lldb_private::formatters::LibcxxUniquePtrSyntheticFrontEnd::GetChildAtIndex(
   return lldb::ValueObjectSP();
 }
 
-bool lldb_private::formatters::LibcxxUniquePtrSyntheticFrontEnd::Update() {
+lldb::ChildCacheState
+lldb_private::formatters::LibcxxUniquePtrSyntheticFrontEnd::Update() {
   ValueObjectSP valobj_sp = m_backend.GetSP();
   if (!valobj_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
   ValueObjectSP ptr_sp(valobj_sp->GetChildMemberWithName("__ptr_"));
   if (!ptr_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
   // Retrieve the actual pointer and the deleter, and clone them to give them
   // user-friendly names.
@@ -708,7 +711,7 @@ bool lldb_private::formatters::LibcxxUniquePtrSyntheticFrontEnd::Update() {
   if (deleter_sp)
     m_deleter_sp = deleter_sp->Clone(ConstString("deleter"));
 
-  return false;
+  return lldb::ChildCacheState::eRefetch;
 }
 
 bool lldb_private::formatters::LibcxxUniquePtrSyntheticFrontEnd::

diff --git a/lldb/source/Plugins/Language/CPlusPlus/LibCxx.h b/lldb/source/Plugins/Language/CPlusPlus/LibCxx.h
@@ -91,7 +91,7 @@ class LibCxxMapIteratorSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
 
   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
 
-  bool Update() override;
+  lldb::ChildCacheState Update() override;
 
   bool MightHaveChildren() override;
 
@@ -139,7 +139,7 @@ class LibCxxUnorderedMapIteratorSyntheticFrontEnd
 
   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
 
-  bool Update() override;
+  lldb::ChildCacheState Update() override;
 
   bool MightHaveChildren() override;
 
@@ -170,7 +170,7 @@ class LibcxxSharedPtrSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
 
   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
 
-  bool Update() override;
+  lldb::ChildCacheState Update() override;
 
   bool MightHaveChildren() override;
 
@@ -190,7 +190,7 @@ class LibcxxUniquePtrSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
 
   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
 
-  bool Update() override;
+  lldb::ChildCacheState Update() override;
 
   bool MightHaveChildren() override;
 

diff --git a/lldb/source/Plugins/Language/CPlusPlus/LibCxxAtomic.cpp b/lldb/source/Plugins/Language/CPlusPlus/LibCxxAtomic.cpp
@@ -94,7 +94,7 @@ class LibcxxStdAtomicSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
 
   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
 
-  bool Update() override;
+  lldb::ChildCacheState Update() override;
 
   bool MightHaveChildren() override;
 
@@ -110,12 +110,13 @@ lldb_private::formatters::LibcxxStdAtomicSyntheticFrontEnd::
     LibcxxStdAtomicSyntheticFrontEnd(lldb::ValueObjectSP valobj_sp)
     : SyntheticChildrenFrontEnd(*valobj_sp) {}
 
-bool lldb_private::formatters::LibcxxStdAtomicSyntheticFrontEnd::Update() {
+lldb::ChildCacheState
+lldb_private::formatters::LibcxxStdAtomicSyntheticFrontEnd::Update() {
   ValueObjectSP atomic_value = GetLibCxxAtomicValue(m_backend);
   if (atomic_value)
     m_real_child = GetLibCxxAtomicValue(m_backend).get();
 
-  return false;
+  return lldb::ChildCacheState::eRefetch;
 }
 
 bool lldb_private::formatters::LibcxxStdAtomicSyntheticFrontEnd::

diff --git a/lldb/source/Plugins/Language/CPlusPlus/LibCxxInitializerList.cpp b/lldb/source/Plugins/Language/CPlusPlus/LibCxxInitializerList.cpp
@@ -30,7 +30,7 @@ class LibcxxInitializerListSyntheticFrontEnd
 
   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
 
-  bool Update() override;
+  lldb::ChildCacheState Update() override;
 
   bool MightHaveChildren() override;
 
@@ -82,21 +82,21 @@ lldb::ValueObjectSP lldb_private::formatters::
                                       m_element_type);
 }
 
-bool lldb_private::formatters::LibcxxInitializerListSyntheticFrontEnd::
-    Update() {
+lldb::ChildCacheState
+lldb_private::formatters::LibcxxInitializerListSyntheticFrontEnd::Update() {
   m_start = nullptr;
   m_num_elements = 0;
   m_element_type = m_backend.GetCompilerType().GetTypeTemplateArgument(0);
   if (!m_element_type.IsValid())
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
   if (std::optional<uint64_t> size = m_element_type.GetByteSize(nullptr)) {
     m_element_size = *size;
     // Store raw pointers or end up with a circular dependency.
     m_start = m_backend.GetChildMemberWithName("__begin_").get();
   }
 
-  return false;
+  return lldb::ChildCacheState::eRefetch;
 }
 
 bool lldb_private::formatters::LibcxxInitializerListSyntheticFrontEnd::

diff --git a/lldb/source/Plugins/Language/CPlusPlus/LibCxxList.cpp b/lldb/source/Plugins/Language/CPlusPlus/LibCxxList.cpp
@@ -109,7 +109,7 @@ class AbstractListFrontEnd : public SyntheticChildrenFrontEnd {
     return ExtractIndexFromString(name.GetCString());
   }
   bool MightHaveChildren() override { return true; }
-  bool Update() override;
+  lldb::ChildCacheState Update() override;
 
 protected:
   AbstractListFrontEnd(ValueObject &valobj)
@@ -138,7 +138,7 @@ class ForwardListFrontEnd : public AbstractListFrontEnd {
 
   size_t CalculateNumChildren() override;
   ValueObjectSP GetChildAtIndex(size_t idx) override;
-  bool Update() override;
+  lldb::ChildCacheState Update() override;
 };
 
 class ListFrontEnd : public AbstractListFrontEnd {
@@ -151,7 +151,7 @@ class ListFrontEnd : public AbstractListFrontEnd {
 
   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
 
-  bool Update() override;
+  lldb::ChildCacheState Update() override;
 
 private:
   lldb::addr_t m_node_address = 0;
@@ -160,7 +160,7 @@ class ListFrontEnd : public AbstractListFrontEnd {
 
 } // end anonymous namespace
 
-bool AbstractListFrontEnd::Update() {
+lldb::ChildCacheState AbstractListFrontEnd::Update() {
   m_loop_detected = 0;
   m_count = UINT32_MAX;
   m_head = nullptr;
@@ -180,10 +180,10 @@ bool AbstractListFrontEnd::Update() {
     list_type = list_type.GetNonReferenceType();
 
   if (list_type.GetNumTemplateArguments() == 0)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   m_element_type = list_type.GetTypeTemplateArgument(0);
 
-  return false;
+  return lldb::ChildCacheState::eRefetch;
 }
 
 bool AbstractListFrontEnd::HasLoop(size_t count) {
@@ -284,22 +284,22 @@ ValueObjectSP ForwardListFrontEnd::GetChildAtIndex(size_t idx) {
                                    m_element_type);
 }
 
-bool ForwardListFrontEnd::Update() {
+lldb::ChildCacheState ForwardListFrontEnd::Update() {
   AbstractListFrontEnd::Update();
 
   Status err;
   ValueObjectSP backend_addr(m_backend.AddressOf(err));
   if (err.Fail() || !backend_addr)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
   ValueObjectSP impl_sp(m_backend.GetChildMemberWithName("__before_begin_"));
   if (!impl_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   impl_sp = GetFirstValueOfLibCXXCompressedPair(*impl_sp);
   if (!impl_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   m_head = impl_sp->GetChildMemberWithName("__next_").get();
-  return false;
+  return lldb::ChildCacheState::eRefetch;
 }
 
 ListFrontEnd::ListFrontEnd(lldb::ValueObjectSP valobj_sp)
@@ -394,24 +394,24 @@ lldb::ValueObjectSP ListFrontEnd::GetChildAtIndex(size_t idx) {
                                    m_element_type);
 }
 
-bool ListFrontEnd::Update() {
+lldb::ChildCacheState ListFrontEnd::Update() {
   AbstractListFrontEnd::Update();
   m_tail = nullptr;
   m_node_address = 0;
 
   Status err;
   ValueObjectSP backend_addr(m_backend.AddressOf(err));
   if (err.Fail() || !backend_addr)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   m_node_address = backend_addr->GetValueAsUnsigned(0);
   if (!m_node_address || m_node_address == LLDB_INVALID_ADDRESS)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   ValueObjectSP impl_sp(m_backend.GetChildMemberWithName("__end_"));
   if (!impl_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   m_head = impl_sp->GetChildMemberWithName("__next_").get();
   m_tail = impl_sp->GetChildMemberWithName("__prev_").get();
-  return false;
+  return lldb::ChildCacheState::eRefetch;
 }
 
 SyntheticChildrenFrontEnd *formatters::LibcxxStdListSyntheticFrontEndCreator(

diff --git a/lldb/source/Plugins/Language/CPlusPlus/LibCxxMap.cpp b/lldb/source/Plugins/Language/CPlusPlus/LibCxxMap.cpp
@@ -181,7 +181,7 @@ class LibcxxStdMapSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
 
   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
 
-  bool Update() override;
+  lldb::ChildCacheState Update() override;
 
   bool MightHaveChildren() override;
 
@@ -405,15 +405,16 @@ lldb_private::formatters::LibcxxStdMapSyntheticFrontEnd::GetChildAtIndex(
   return potential_child_sp;
 }
 
-bool lldb_private::formatters::LibcxxStdMapSyntheticFrontEnd::Update() {
+lldb::ChildCacheState
+lldb_private::formatters::LibcxxStdMapSyntheticFrontEnd::Update() {
   m_count = UINT32_MAX;
   m_tree = m_root_node = nullptr;
   m_iterators.clear();
   m_tree = m_backend.GetChildMemberWithName("__tree_").get();
   if (!m_tree)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   m_root_node = m_tree->GetChildMemberWithName("__begin_node_").get();
-  return false;
+  return lldb::ChildCacheState::eRefetch;
 }
 
 bool lldb_private::formatters::LibcxxStdMapSyntheticFrontEnd::

diff --git a/lldb/source/Plugins/Language/CPlusPlus/LibCxxQueue.cpp b/lldb/source/Plugins/Language/CPlusPlus/LibCxxQueue.cpp
@@ -26,7 +26,7 @@ class QueueFrontEnd : public SyntheticChildrenFrontEnd {
   }
 
   bool MightHaveChildren() override { return true; }
-  bool Update() override;
+  lldb::ChildCacheState Update() override;
 
   size_t CalculateNumChildren() override {
     return m_container_sp ? m_container_sp->GetNumChildren() : 0;
@@ -47,13 +47,13 @@ class QueueFrontEnd : public SyntheticChildrenFrontEnd {
 };
 } // namespace
 
-bool QueueFrontEnd::Update() {
+lldb::ChildCacheState QueueFrontEnd::Update() {
   m_container_sp = nullptr;
   ValueObjectSP c_sp = m_backend.GetChildMemberWithName("c");
   if (!c_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   m_container_sp = c_sp->GetSyntheticValue().get();
-  return false;
+  return lldb::ChildCacheState::eRefetch;
 }
 
 SyntheticChildrenFrontEnd *

diff --git a/lldb/source/Plugins/Language/CPlusPlus/LibCxxRangesRefView.cpp b/lldb/source/Plugins/Language/CPlusPlus/LibCxxRangesRefView.cpp
@@ -38,7 +38,7 @@ class LibcxxStdRangesRefViewSyntheticFrontEnd
     return m_range_sp;
   }
 
-  bool Update() override;
+  lldb::ChildCacheState Update() override;
 
   bool MightHaveChildren() override { return true; }
 
@@ -59,17 +59,18 @@ lldb_private::formatters::LibcxxStdRangesRefViewSyntheticFrontEnd::
     Update();
 }
 
-bool lldb_private::formatters::LibcxxStdRangesRefViewSyntheticFrontEnd::
-    Update() {
+lldb::ChildCacheState
+lldb_private::formatters::LibcxxStdRangesRefViewSyntheticFrontEnd::Update() {
   ValueObjectSP range_ptr =
       GetChildMemberWithName(m_backend, {ConstString("__range_")});
   if (!range_ptr)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
   lldb_private::Status error;
   m_range_sp = range_ptr->Dereference(error);
 
-  return error.Success();
+  return error.Success() ? lldb::ChildCacheState::eReuse
+                         : lldb::ChildCacheState::eRefetch;
 }
 
 lldb_private::SyntheticChildrenFrontEnd *

diff --git a/lldb/source/Plugins/Language/CPlusPlus/LibCxxSpan.cpp b/lldb/source/Plugins/Language/CPlusPlus/LibCxxSpan.cpp
@@ -53,7 +53,7 @@ class LibcxxStdSpanSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
   // This function checks for a '__size' member to determine the number
   // of elements in the span. If no such member exists, we get the size
   // from the only other place it can be: the template argument.
-  bool Update() override;
+  lldb::ChildCacheState Update() override;
 
   bool MightHaveChildren() override;
 
@@ -93,12 +93,13 @@ lldb_private::formatters::LibcxxStdSpanSyntheticFrontEnd::GetChildAtIndex(
                                       m_element_type);
 }
 
-bool lldb_private::formatters::LibcxxStdSpanSyntheticFrontEnd::Update() {
+lldb::ChildCacheState
+lldb_private::formatters::LibcxxStdSpanSyntheticFrontEnd::Update() {
   // Get element type.
   ValueObjectSP data_type_finder_sp = GetChildMemberWithName(
       m_backend, {ConstString("__data_"), ConstString("__data")});
   if (!data_type_finder_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
   m_element_type = data_type_finder_sp->GetCompilerType().GetPointeeType();
 
@@ -122,7 +123,7 @@ bool lldb_private::formatters::LibcxxStdSpanSyntheticFrontEnd::Update() {
     }
   }
 
-  return true;
+  return lldb::ChildCacheState::eReuse;
 }
 
 bool lldb_private::formatters::LibcxxStdSpanSyntheticFrontEnd::

diff --git a/lldb/source/Plugins/Language/CPlusPlus/LibCxxTuple.cpp b/lldb/source/Plugins/Language/CPlusPlus/LibCxxTuple.cpp
@@ -25,7 +25,7 @@ class TupleFrontEnd: public SyntheticChildrenFrontEnd {
   }
 
   bool MightHaveChildren() override { return true; }
-  bool Update() override;
+  lldb::ChildCacheState Update() override;
   size_t CalculateNumChildren() override { return m_elements.size(); }
   ValueObjectSP GetChildAtIndex(size_t idx) override;
 
@@ -40,7 +40,7 @@ class TupleFrontEnd: public SyntheticChildrenFrontEnd {
 };
 }
 
-bool TupleFrontEnd::Update() {
+lldb::ChildCacheState TupleFrontEnd::Update() {
   m_elements.clear();
   m_base = nullptr;
 
@@ -51,11 +51,11 @@ bool TupleFrontEnd::Update() {
     base_sp = m_backend.GetChildMemberWithName("base_");
   }
   if (!base_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   m_base = base_sp.get();
   m_elements.assign(base_sp->GetCompilerType().GetNumDirectBaseClasses(),
                     nullptr);
-  return false;
+  return lldb::ChildCacheState::eRefetch;
 }
 
 ValueObjectSP TupleFrontEnd::GetChildAtIndex(size_t idx) {

diff --git a/lldb/source/Plugins/Language/CPlusPlus/LibCxxUnorderedMap.cpp b/lldb/source/Plugins/Language/CPlusPlus/LibCxxUnorderedMap.cpp
@@ -37,7 +37,7 @@ class LibcxxStdUnorderedMapSyntheticFrontEnd
 
   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
 
-  bool Update() override;
+  lldb::ChildCacheState Update() override;
 
   bool MightHaveChildren() override;
 
@@ -193,41 +193,41 @@ lldb::ValueObjectSP lldb_private::formatters::
                                    m_element_type);
 }
 
-bool lldb_private::formatters::LibcxxStdUnorderedMapSyntheticFrontEnd::
-    Update() {
+lldb::ChildCacheState
+lldb_private::formatters::LibcxxStdUnorderedMapSyntheticFrontEnd::Update() {
   m_num_elements = 0;
   m_next_element = nullptr;
   m_elements_cache.clear();
   ValueObjectSP table_sp = m_backend.GetChildMemberWithName("__table_");
   if (!table_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
   ValueObjectSP p2_sp = table_sp->GetChildMemberWithName("__p2_");
   if (!p2_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
   ValueObjectSP num_elements_sp = GetFirstValueOfLibCXXCompressedPair(*p2_sp);
   if (!num_elements_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
   ValueObjectSP p1_sp = table_sp->GetChildMemberWithName("__p1_");
   if (!p1_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
   ValueObjectSP value_sp = GetFirstValueOfLibCXXCompressedPair(*p1_sp);
   if (!value_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
   m_tree = value_sp->GetChildMemberWithName("__next_").get();
   if (m_tree == nullptr)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
   m_num_elements = num_elements_sp->GetValueAsUnsigned(0);
 
   if (m_num_elements > 0)
     m_next_element = m_tree;
 
-  return false;
+  return lldb::ChildCacheState::eRefetch;
 }
 
 bool lldb_private::formatters::LibcxxStdUnorderedMapSyntheticFrontEnd::

diff --git a/lldb/source/Plugins/Language/CPlusPlus/LibCxxVariant.cpp b/lldb/source/Plugins/Language/CPlusPlus/LibCxxVariant.cpp
@@ -204,7 +204,7 @@ class VariantFrontEnd : public SyntheticChildrenFrontEnd {
   }
 
   bool MightHaveChildren() override { return true; }
-  bool Update() override;
+  lldb::ChildCacheState Update() override;
   size_t CalculateNumChildren() override { return m_size; }
   ValueObjectSP GetChildAtIndex(size_t idx) override;
 
@@ -213,24 +213,24 @@ class VariantFrontEnd : public SyntheticChildrenFrontEnd {
 };
 } // namespace
 
-bool VariantFrontEnd::Update() {
+lldb::ChildCacheState VariantFrontEnd::Update() {
   m_size = 0;
   ValueObjectSP impl_sp = formatters::GetChildMemberWithName(
       m_backend, {ConstString("__impl_"), ConstString("__impl")});
   if (!impl_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
   LibcxxVariantIndexValidity validity = LibcxxVariantGetIndexValidity(impl_sp);
 
   if (validity == LibcxxVariantIndexValidity::Invalid)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
   if (validity == LibcxxVariantIndexValidity::NPos)
-    return true;
+    return lldb::ChildCacheState::eReuse;
 
   m_size = 1;
 
-  return false;
+  return lldb::ChildCacheState::eRefetch;
 }
 
 ValueObjectSP VariantFrontEnd::GetChildAtIndex(size_t idx) {

diff --git a/lldb/source/Plugins/Language/CPlusPlus/LibCxxVector.cpp b/lldb/source/Plugins/Language/CPlusPlus/LibCxxVector.cpp
@@ -29,7 +29,7 @@ class LibcxxStdVectorSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
 
   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
 
-  bool Update() override;
+  lldb::ChildCacheState Update() override;
 
   bool MightHaveChildren() override;
 
@@ -50,7 +50,7 @@ class LibcxxVectorBoolSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
 
   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
 
-  bool Update() override;
+  lldb::ChildCacheState Update() override;
 
   bool MightHaveChildren() override { return true; }
 
@@ -116,17 +116,18 @@ lldb_private::formatters::LibcxxStdVectorSyntheticFrontEnd::GetChildAtIndex(
                                       m_element_type);
 }
 
-bool lldb_private::formatters::LibcxxStdVectorSyntheticFrontEnd::Update() {
+lldb::ChildCacheState
+lldb_private::formatters::LibcxxStdVectorSyntheticFrontEnd::Update() {
   m_start = m_finish = nullptr;
   ValueObjectSP data_type_finder_sp(
       m_backend.GetChildMemberWithName("__end_cap_"));
   if (!data_type_finder_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
   data_type_finder_sp =
       GetFirstValueOfLibCXXCompressedPair(*data_type_finder_sp);
   if (!data_type_finder_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
   m_element_type = data_type_finder_sp->GetCompilerType().GetPointeeType();
   if (std::optional<uint64_t> size = m_element_type.GetByteSize(nullptr)) {
@@ -138,7 +139,7 @@ bool lldb_private::formatters::LibcxxStdVectorSyntheticFrontEnd::Update() {
       m_finish = m_backend.GetChildMemberWithName("__end_").get();
     }
   }
-  return false;
+  return lldb::ChildCacheState::eRefetch;
 }
 
 bool lldb_private::formatters::LibcxxStdVectorSyntheticFrontEnd::
@@ -226,29 +227,30 @@ lldb_private::formatters::LibcxxVectorBoolSyntheticFrontEnd::GetChildAtIndex(
  }
  }*/
 
-bool lldb_private::formatters::LibcxxVectorBoolSyntheticFrontEnd::Update() {
+lldb::ChildCacheState
+lldb_private::formatters::LibcxxVectorBoolSyntheticFrontEnd::Update() {
   m_children.clear();
   ValueObjectSP valobj_sp = m_backend.GetSP();
   if (!valobj_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   m_exe_ctx_ref = valobj_sp->GetExecutionContextRef();
   ValueObjectSP size_sp(valobj_sp->GetChildMemberWithName("__size_"));
   if (!size_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   m_count = size_sp->GetValueAsUnsigned(0);
   if (!m_count)
-    return true;
+    return lldb::ChildCacheState::eReuse;
   ValueObjectSP begin_sp(valobj_sp->GetChildMemberWithName("__begin_"));
   if (!begin_sp) {
     m_count = 0;
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   }
   m_base_data_address = begin_sp->GetValueAsUnsigned(0);
   if (!m_base_data_address) {
     m_count = 0;
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   }
-  return false;
+  return lldb::ChildCacheState::eRefetch;
 }
 
 size_t lldb_private::formatters::LibcxxVectorBoolSyntheticFrontEnd::

diff --git a/lldb/source/Plugins/Language/CPlusPlus/LibStdcpp.cpp b/lldb/source/Plugins/Language/CPlusPlus/LibStdcpp.cpp
@@ -47,7 +47,7 @@ class LibstdcppMapIteratorSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
 
   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
 
-  bool Update() override;
+  lldb::ChildCacheState Update() override;
 
   bool MightHaveChildren() override;
 
@@ -68,7 +68,7 @@ class LibStdcppSharedPtrSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
 
   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
 
-  bool Update() override;
+  lldb::ChildCacheState Update() override;
 
   bool MightHaveChildren() override;
 
@@ -94,42 +94,42 @@ LibstdcppMapIteratorSyntheticFrontEnd::LibstdcppMapIteratorSyntheticFrontEnd(
     Update();
 }
 
-bool LibstdcppMapIteratorSyntheticFrontEnd::Update() {
+lldb::ChildCacheState LibstdcppMapIteratorSyntheticFrontEnd::Update() {
   ValueObjectSP valobj_sp = m_backend.GetSP();
   if (!valobj_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
   TargetSP target_sp(valobj_sp->GetTargetSP());
 
   if (!target_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
   bool is_64bit = (target_sp->GetArchitecture().GetAddressByteSize() == 8);
 
   if (!valobj_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   m_exe_ctx_ref = valobj_sp->GetExecutionContextRef();
 
   ValueObjectSP _M_node_sp(valobj_sp->GetChildMemberWithName("_M_node"));
   if (!_M_node_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
   m_pair_address = _M_node_sp->GetValueAsUnsigned(0);
   if (m_pair_address == 0)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
   m_pair_address += (is_64bit ? 32 : 16);
 
   CompilerType my_type(valobj_sp->GetCompilerType());
   if (my_type.GetNumTemplateArguments() >= 1) {
     CompilerType pair_type = my_type.GetTypeTemplateArgument(0);
     if (!pair_type)
-      return false;
+      return lldb::ChildCacheState::eRefetch;
     m_pair_type = pair_type;
   } else
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
-  return true;
+  return lldb::ChildCacheState::eReuse;
 }
 
 size_t LibstdcppMapIteratorSyntheticFrontEnd::CalculateNumChildren() {
@@ -193,30 +193,30 @@ lldb_private::formatters::VectorIteratorSyntheticFrontEnd::
     Update();
 }
 
-bool VectorIteratorSyntheticFrontEnd::Update() {
+lldb::ChildCacheState VectorIteratorSyntheticFrontEnd::Update() {
   m_item_sp.reset();
 
   ValueObjectSP valobj_sp = m_backend.GetSP();
   if (!valobj_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
   if (!valobj_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
   ValueObjectSP item_ptr =
       formatters::GetChildMemberWithName(*valobj_sp, m_item_names);
   if (!item_ptr)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   if (item_ptr->GetValueAsUnsigned(0) == 0)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   Status err;
   m_exe_ctx_ref = valobj_sp->GetExecutionContextRef();
   m_item_sp = CreateValueObjectFromAddress(
       "item", item_ptr->GetValueAsUnsigned(0), m_exe_ctx_ref,
       item_ptr->GetCompilerType().GetPointeeType());
   if (err.Fail())
     m_item_sp.reset();
-  return false;
+  return lldb::ChildCacheState::eRefetch;
 }
 
 size_t VectorIteratorSyntheticFrontEnd::CalculateNumChildren() { return 1; }
@@ -390,23 +390,23 @@ LibStdcppSharedPtrSyntheticFrontEnd::GetChildAtIndex(size_t idx) {
   return lldb::ValueObjectSP();
 }
 
-bool LibStdcppSharedPtrSyntheticFrontEnd::Update() {
+lldb::ChildCacheState LibStdcppSharedPtrSyntheticFrontEnd::Update() {
   auto backend = m_backend.GetSP();
   if (!backend)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
   auto valobj_sp = backend->GetNonSyntheticValue();
   if (!valobj_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
   auto ptr_obj_sp = valobj_sp->GetChildMemberWithName("_M_ptr");
   if (!ptr_obj_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
   m_ptr_obj = ptr_obj_sp->Clone(ConstString("pointer")).get();
   m_obj_obj = nullptr;
 
-  return false;
+  return lldb::ChildCacheState::eRefetch;
 }
 
 bool LibStdcppSharedPtrSyntheticFrontEnd::MightHaveChildren() { return true; }

diff --git a/lldb/source/Plugins/Language/CPlusPlus/LibStdcppTuple.cpp b/lldb/source/Plugins/Language/CPlusPlus/LibStdcppTuple.cpp
@@ -30,7 +30,7 @@ class LibStdcppTupleSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
 
   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
 
-  bool Update() override;
+  lldb::ChildCacheState Update() override;
 
   bool MightHaveChildren() override;
 
@@ -53,12 +53,12 @@ LibStdcppTupleSyntheticFrontEnd::LibStdcppTupleSyntheticFrontEnd(
   Update();
 }
 
-bool LibStdcppTupleSyntheticFrontEnd::Update() {
+lldb::ChildCacheState LibStdcppTupleSyntheticFrontEnd::Update() {
   m_members.clear();
 
   ValueObjectSP valobj_backend_sp = m_backend.GetSP();
   if (!valobj_backend_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
   ValueObjectSP next_child_sp = valobj_backend_sp->GetNonSyntheticValue();
   while (next_child_sp != nullptr) {
@@ -83,7 +83,7 @@ bool LibStdcppTupleSyntheticFrontEnd::Update() {
     }
   }
 
-  return false;
+  return lldb::ChildCacheState::eRefetch;
 }
 
 bool LibStdcppTupleSyntheticFrontEnd::MightHaveChildren() { return true; }

diff --git a/lldb/source/Plugins/Language/CPlusPlus/LibStdcppUniquePointer.cpp b/lldb/source/Plugins/Language/CPlusPlus/LibStdcppUniquePointer.cpp
@@ -30,7 +30,7 @@ class LibStdcppUniquePtrSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
 
   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
 
-  bool Update() override;
+  lldb::ChildCacheState Update() override;
 
   bool MightHaveChildren() override;
 
@@ -84,11 +84,11 @@ ValueObjectSP LibStdcppUniquePtrSyntheticFrontEnd::GetTuple() {
   return obj_child_sp;
 }
 
-bool LibStdcppUniquePtrSyntheticFrontEnd::Update() {
+lldb::ChildCacheState LibStdcppUniquePtrSyntheticFrontEnd::Update() {
   ValueObjectSP tuple_sp = GetTuple();
 
   if (!tuple_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
 
   std::unique_ptr<SyntheticChildrenFrontEnd> tuple_frontend(
       LibStdcppTupleSyntheticFrontEndCreator(nullptr, tuple_sp));
@@ -110,7 +110,7 @@ bool LibStdcppUniquePtrSyntheticFrontEnd::Update() {
   }
   m_obj_obj = nullptr;
 
-  return false;
+  return lldb::ChildCacheState::eRefetch;
 }
 
 bool LibStdcppUniquePtrSyntheticFrontEnd::MightHaveChildren() { return true; }

diff --git a/lldb/source/Plugins/Language/ObjC/Cocoa.cpp b/lldb/source/Plugins/Language/ObjC/Cocoa.cpp
@@ -1044,7 +1044,9 @@ class ObjCClassSyntheticChildrenFrontEnd : public SyntheticChildrenFrontEnd {
     return lldb::ValueObjectSP();
   }
 
-  bool Update() override { return false; }
+  lldb::ChildCacheState Update() override {
+    return lldb::ChildCacheState::eRefetch;
+  }
 
   bool MightHaveChildren() override { return false; }
 

diff --git a/lldb/source/Plugins/Language/ObjC/NSArray.cpp b/lldb/source/Plugins/Language/ObjC/NSArray.cpp
@@ -54,7 +54,7 @@ class NSArrayMSyntheticFrontEndBase : public SyntheticChildrenFrontEnd {
 
   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
 
-  bool Update() override = 0;
+  lldb::ChildCacheState Update() override = 0;
 
   bool MightHaveChildren() override;
 
@@ -81,7 +81,7 @@ class GenericNSArrayMSyntheticFrontEnd : public NSArrayMSyntheticFrontEndBase {
 
   ~GenericNSArrayMSyntheticFrontEnd() override;
 
-  bool Update() override;
+  lldb::ChildCacheState Update() override;
 
 protected:
   lldb::addr_t GetDataAddress() override;
@@ -218,7 +218,7 @@ class GenericNSArrayISyntheticFrontEnd : public SyntheticChildrenFrontEnd {
 
   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
 
-  bool Update() override;
+  lldb::ChildCacheState Update() override;
 
   bool MightHaveChildren() override;
 
@@ -306,7 +306,7 @@ class NSArray0SyntheticFrontEnd : public SyntheticChildrenFrontEnd {
 
   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
 
-  bool Update() override;
+  lldb::ChildCacheState Update() override;
 
   bool MightHaveChildren() override;
 
@@ -323,7 +323,7 @@ class NSArray1SyntheticFrontEnd : public SyntheticChildrenFrontEnd {
 
   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
 
-  bool Update() override;
+  lldb::ChildCacheState Update() override;
 
   bool MightHaveChildren() override;
 
@@ -500,23 +500,22 @@ lldb_private::formatters::NSArrayMSyntheticFrontEndBase::GetChildAtIndex(
 }
 
 template <typename D32, typename D64>
-bool
-lldb_private::formatters::
-  GenericNSArrayMSyntheticFrontEnd<D32, D64>::Update() {
+lldb::ChildCacheState
+lldb_private::formatters::GenericNSArrayMSyntheticFrontEnd<D32, D64>::Update() {
   ValueObjectSP valobj_sp = m_backend.GetSP();
   m_ptr_size = 0;
   delete m_data_32;
   m_data_32 = nullptr;
   delete m_data_64;
   m_data_64 = nullptr;
   if (!valobj_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   m_exe_ctx_ref = valobj_sp->GetExecutionContextRef();
   Status error;
   error.Clear();
   lldb::ProcessSP process_sp(valobj_sp->GetProcessSP());
   if (!process_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   m_ptr_size = process_sp->GetAddressByteSize();
   uint64_t data_location = valobj_sp->GetValueAsUnsigned(0) + m_ptr_size;
   if (m_ptr_size == 4) {
@@ -529,7 +528,8 @@ lldb_private::formatters::
                            error);
   }
 
-  return error.Success();
+  return error.Success() ? lldb::ChildCacheState::eReuse
+                         : lldb::ChildCacheState::eRefetch;
 }
 
 bool
@@ -641,23 +641,23 @@ lldb_private::formatters::GenericNSArrayISyntheticFrontEnd<D32, D64, Inline>::
 }
 
 template <typename D32, typename D64, bool Inline>
-bool
-lldb_private::formatters::GenericNSArrayISyntheticFrontEnd<D32, D64, Inline>::
-  Update() {
+lldb::ChildCacheState
+lldb_private::formatters::GenericNSArrayISyntheticFrontEnd<D32, D64,
+                                                           Inline>::Update() {
   ValueObjectSP valobj_sp = m_backend.GetSP();
   m_ptr_size = 0;
   delete m_data_32;
   m_data_32 = nullptr;
   delete m_data_64;
   m_data_64 = nullptr;
   if (!valobj_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   m_exe_ctx_ref = valobj_sp->GetExecutionContextRef();
   Status error;
   error.Clear();
   lldb::ProcessSP process_sp(valobj_sp->GetProcessSP());
   if (!process_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   m_ptr_size = process_sp->GetAddressByteSize();
   uint64_t data_location = valobj_sp->GetValueAsUnsigned(0) + m_ptr_size;
   if (m_ptr_size == 4) {
@@ -670,7 +670,8 @@ lldb_private::formatters::GenericNSArrayISyntheticFrontEnd<D32, D64, Inline>::
                            error);
   }
 
-  return error.Success();
+  return error.Success() ? lldb::ChildCacheState::eReuse
+                         : lldb::ChildCacheState::eRefetch;
 }
 
 template <typename D32, typename D64, bool Inline>
@@ -723,8 +724,9 @@ lldb_private::formatters::NSArray0SyntheticFrontEnd::CalculateNumChildren() {
   return 0;
 }
 
-bool lldb_private::formatters::NSArray0SyntheticFrontEnd::Update() {
-  return false;
+lldb::ChildCacheState
+lldb_private::formatters::NSArray0SyntheticFrontEnd::Update() {
+  return lldb::ChildCacheState::eRefetch;
 }
 
 bool lldb_private::formatters::NSArray0SyntheticFrontEnd::MightHaveChildren() {
@@ -757,8 +759,9 @@ lldb_private::formatters::NSArray1SyntheticFrontEnd::CalculateNumChildren() {
   return 1;
 }
 
-bool lldb_private::formatters::NSArray1SyntheticFrontEnd::Update() {
-  return false;
+lldb::ChildCacheState
+lldb_private::formatters::NSArray1SyntheticFrontEnd::Update() {
+  return lldb::ChildCacheState::eRefetch;
 }
 
 bool lldb_private::formatters::NSArray1SyntheticFrontEnd::MightHaveChildren() {

diff --git a/lldb/source/Plugins/Language/ObjC/NSDictionary.cpp b/lldb/source/Plugins/Language/ObjC/NSDictionary.cpp
@@ -107,7 +107,7 @@ class NSDictionaryISyntheticFrontEnd : public SyntheticChildrenFrontEnd {
 
   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
 
-  bool Update() override;
+  lldb::ChildCacheState Update() override;
 
   bool MightHaveChildren() override;
 
@@ -148,7 +148,7 @@ class NSConstantDictionarySyntheticFrontEnd : public SyntheticChildrenFrontEnd {
 
   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
 
-  bool Update() override;
+  lldb::ChildCacheState Update() override;
 
   bool MightHaveChildren() override;
 
@@ -180,7 +180,7 @@ class NSCFDictionarySyntheticFrontEnd : public SyntheticChildrenFrontEnd {
 
   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
 
-  bool Update() override;
+  lldb::ChildCacheState Update() override;
 
   bool MightHaveChildren() override;
 
@@ -213,7 +213,7 @@ class NSDictionary1SyntheticFrontEnd : public SyntheticChildrenFrontEnd {
 
   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
 
-  bool Update() override;
+  lldb::ChildCacheState Update() override;
 
   bool MightHaveChildren() override;
 
@@ -234,7 +234,7 @@ class GenericNSDictionaryMSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
 
   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
 
-  bool Update() override;
+  lldb::ChildCacheState Update() override;
 
   bool MightHaveChildren() override;
 
@@ -266,9 +266,9 @@ namespace Foundation1100 {
     size_t CalculateNumChildren() override;
 
     lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
-    
-    bool Update() override;
-    
+
+    lldb::ChildCacheState Update() override;
+
     bool MightHaveChildren() override;
 
     size_t GetIndexOfChildWithName(ConstString name) override;
@@ -613,7 +613,8 @@ size_t lldb_private::formatters::NSDictionaryISyntheticFrontEnd::
   return (m_data_32 ? m_data_32->_used : m_data_64->_used);
 }
 
-bool lldb_private::formatters::NSDictionaryISyntheticFrontEnd::Update() {
+lldb::ChildCacheState
+lldb_private::formatters::NSDictionaryISyntheticFrontEnd::Update() {
   m_children.clear();
   delete m_data_32;
   m_data_32 = nullptr;
@@ -622,13 +623,13 @@ bool lldb_private::formatters::NSDictionaryISyntheticFrontEnd::Update() {
   m_ptr_size = 0;
   ValueObjectSP valobj_sp = m_backend.GetSP();
   if (!valobj_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   m_exe_ctx_ref = valobj_sp->GetExecutionContextRef();
   Status error;
   error.Clear();
   lldb::ProcessSP process_sp(valobj_sp->GetProcessSP());
   if (!process_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   m_ptr_size = process_sp->GetAddressByteSize();
   m_order = process_sp->GetByteOrder();
   uint64_t data_location = valobj_sp->GetValueAsUnsigned(0) + m_ptr_size;
@@ -642,9 +643,9 @@ bool lldb_private::formatters::NSDictionaryISyntheticFrontEnd::Update() {
                            error);
   }
   if (error.Fail())
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   m_data_ptr = data_location + m_ptr_size;
-  return false;
+  return lldb::ChildCacheState::eRefetch;
 }
 
 bool lldb_private::formatters::NSDictionaryISyntheticFrontEnd::
@@ -750,20 +751,23 @@ size_t lldb_private::formatters::NSCFDictionarySyntheticFrontEnd::
   return m_hashtable.GetCount();
 }
 
-bool lldb_private::formatters::NSCFDictionarySyntheticFrontEnd::Update() {
+lldb::ChildCacheState
+lldb_private::formatters::NSCFDictionarySyntheticFrontEnd::Update() {
   m_children.clear();
   ValueObjectSP valobj_sp = m_backend.GetSP();
   m_ptr_size = 0;
   if (!valobj_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   m_exe_ctx_ref = valobj_sp->GetExecutionContextRef();
 
   lldb::ProcessSP process_sp(valobj_sp->GetProcessSP());
   if (!process_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   m_ptr_size = process_sp->GetAddressByteSize();
   m_order = process_sp->GetByteOrder();
-  return m_hashtable.Update(valobj_sp->GetValueAsUnsigned(0), m_exe_ctx_ref);
+  return m_hashtable.Update(valobj_sp->GetValueAsUnsigned(0), m_exe_ctx_ref)
+             ? lldb::ChildCacheState::eReuse
+             : lldb::ChildCacheState::eRefetch;
 }
 
 bool lldb_private::formatters::NSCFDictionarySyntheticFrontEnd::
@@ -881,30 +885,33 @@ size_t lldb_private::formatters::NSConstantDictionarySyntheticFrontEnd::
   return m_size;
 }
 
-bool lldb_private::formatters::NSConstantDictionarySyntheticFrontEnd::Update() {
+lldb::ChildCacheState
+lldb_private::formatters::NSConstantDictionarySyntheticFrontEnd::Update() {
   ValueObjectSP valobj_sp = m_backend.GetSP();
   if (!valobj_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   m_exe_ctx_ref = valobj_sp->GetExecutionContextRef();
   Status error;
   error.Clear();
   lldb::ProcessSP process_sp(valobj_sp->GetProcessSP());
   if (!process_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   m_ptr_size = process_sp->GetAddressByteSize();
   m_order = process_sp->GetByteOrder();
   uint64_t valobj_addr = valobj_sp->GetValueAsUnsigned(0);
   m_size = process_sp->ReadUnsignedIntegerFromMemory(
       valobj_addr + 2 * m_ptr_size, m_ptr_size, 0, error);
   if (error.Fail())
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   m_keys_ptr =
       process_sp->ReadPointerFromMemory(valobj_addr + 3 * m_ptr_size, error);
   if (error.Fail())
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   m_objects_ptr =
       process_sp->ReadPointerFromMemory(valobj_addr + 4 * m_ptr_size, error);
-  return !error.Fail();
+
+  return error.Success() ? lldb::ChildCacheState::eReuse
+                         : lldb::ChildCacheState::eRefetch;
 }
 
 bool lldb_private::formatters::NSConstantDictionarySyntheticFrontEnd::
@@ -992,9 +999,10 @@ size_t lldb_private::formatters::NSDictionary1SyntheticFrontEnd::
   return 1;
 }
 
-bool lldb_private::formatters::NSDictionary1SyntheticFrontEnd::Update() {
+lldb::ChildCacheState
+lldb_private::formatters::NSDictionary1SyntheticFrontEnd::Update() {
   m_pair.reset();
-  return false;
+  return lldb::ChildCacheState::eRefetch;
 }
 
 bool lldb_private::formatters::NSDictionary1SyntheticFrontEnd::
@@ -1087,9 +1095,9 @@ lldb_private::formatters::GenericNSDictionaryMSyntheticFrontEnd<D32,D64>::Calcul
 }
 
 template <typename D32, typename D64>
-bool
-lldb_private::formatters::GenericNSDictionaryMSyntheticFrontEnd<D32,D64>::
-  Update() {
+lldb::ChildCacheState
+lldb_private::formatters::GenericNSDictionaryMSyntheticFrontEnd<D32,
+                                                                D64>::Update() {
   m_children.clear();
   ValueObjectSP valobj_sp = m_backend.GetSP();
   m_ptr_size = 0;
@@ -1098,13 +1106,13 @@ lldb_private::formatters::GenericNSDictionaryMSyntheticFrontEnd<D32,D64>::
   delete m_data_64;
   m_data_64 = nullptr;
   if (!valobj_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   m_exe_ctx_ref = valobj_sp->GetExecutionContextRef();
   Status error;
   error.Clear();
   lldb::ProcessSP process_sp(valobj_sp->GetProcessSP());
   if (!process_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   m_ptr_size = process_sp->GetAddressByteSize();
   m_order = process_sp->GetByteOrder();
   uint64_t data_location = valobj_sp->GetValueAsUnsigned(0) + m_ptr_size;
@@ -1118,7 +1126,8 @@ lldb_private::formatters::GenericNSDictionaryMSyntheticFrontEnd<D32,D64>::
                            error);
   }
 
-  return error.Success();
+  return error.Success() ? lldb::ChildCacheState::eReuse
+                         : lldb::ChildCacheState::eRefetch;
 }
 
 template <typename D32, typename D64>
@@ -1249,9 +1258,8 @@ lldb_private::formatters::Foundation1100::
   return (m_data_32 ? m_data_32->_used : m_data_64->_used);
 }
 
-bool
-lldb_private::formatters::Foundation1100::
-  NSDictionaryMSyntheticFrontEnd::Update() {
+lldb::ChildCacheState lldb_private::formatters::Foundation1100::
+    NSDictionaryMSyntheticFrontEnd::Update() {
   m_children.clear();
   ValueObjectSP valobj_sp = m_backend.GetSP();
   m_ptr_size = 0;
@@ -1260,13 +1268,13 @@ lldb_private::formatters::Foundation1100::
   delete m_data_64;
   m_data_64 = nullptr;
   if (!valobj_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   m_exe_ctx_ref = valobj_sp->GetExecutionContextRef();
   Status error;
   error.Clear();
   lldb::ProcessSP process_sp(valobj_sp->GetProcessSP());
   if (!process_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   m_ptr_size = process_sp->GetAddressByteSize();
   m_order = process_sp->GetByteOrder();
   uint64_t data_location = valobj_sp->GetValueAsUnsigned(0) + m_ptr_size;
@@ -1280,7 +1288,8 @@ lldb_private::formatters::Foundation1100::
                            error);
   }
 
-  return error.Success();
+  return error.Success() ? lldb::ChildCacheState::eReuse
+                         : lldb::ChildCacheState::eRefetch;
 }
 
 bool

diff --git a/lldb/source/Plugins/Language/ObjC/NSError.cpp b/lldb/source/Plugins/Language/ObjC/NSError.cpp
@@ -133,17 +133,17 @@ class NSErrorSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
     return m_child_sp;
   }
 
-  bool Update() override {
+  lldb::ChildCacheState Update() override {
     m_child_ptr = nullptr;
     m_child_sp.reset();
 
     ProcessSP process_sp(m_backend.GetProcessSP());
     if (!process_sp)
-      return false;
+      return lldb::ChildCacheState::eRefetch;
 
     lldb::addr_t userinfo_location = DerefToNSErrorPointer(m_backend);
     if (userinfo_location == LLDB_INVALID_ADDRESS)
-      return false;
+      return lldb::ChildCacheState::eRefetch;
 
     size_t ptr_size = process_sp->GetAddressByteSize();
 
@@ -152,17 +152,17 @@ class NSErrorSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
     lldb::addr_t userinfo =
         process_sp->ReadPointerFromMemory(userinfo_location, error);
     if (userinfo == LLDB_INVALID_ADDRESS || error.Fail())
-      return false;
+      return lldb::ChildCacheState::eRefetch;
     InferiorSizedWord isw(userinfo, *process_sp);
     TypeSystemClangSP scratch_ts_sp =
         ScratchTypeSystemClang::GetForTarget(process_sp->GetTarget());
     if (!scratch_ts_sp)
-      return false;
+      return lldb::ChildCacheState::eRefetch;
     m_child_sp = CreateValueObjectFromData(
         "_userInfo", isw.GetAsData(process_sp->GetByteOrder()),
         m_backend.GetExecutionContextRef(),
         scratch_ts_sp->GetBasicType(lldb::eBasicTypeObjCID));
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   }
 
   bool MightHaveChildren() override { return true; }

diff --git a/lldb/source/Plugins/Language/ObjC/NSException.cpp b/lldb/source/Plugins/Language/ObjC/NSException.cpp
@@ -137,14 +137,17 @@ class NSExceptionSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
     return lldb::ValueObjectSP();
   }
 
-  bool Update() override {
+  lldb::ChildCacheState Update() override {
     m_name_sp.reset();
     m_reason_sp.reset();
     m_userinfo_sp.reset();
     m_reserved_sp.reset();
 
-    return ExtractFields(m_backend, &m_name_sp, &m_reason_sp, &m_userinfo_sp,
-                         &m_reserved_sp);
+    const auto ret = ExtractFields(m_backend, &m_name_sp, &m_reason_sp,
+                                   &m_userinfo_sp, &m_reserved_sp);
+
+    return ret ? lldb::ChildCacheState::eReuse
+               : lldb::ChildCacheState::eRefetch;
   }
 
   bool MightHaveChildren() override { return true; }

diff --git a/lldb/source/Plugins/Language/ObjC/NSIndexPath.cpp b/lldb/source/Plugins/Language/ObjC/NSIndexPath.cpp
@@ -46,17 +46,17 @@ class NSIndexPathSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
     return m_impl.GetIndexAtIndex(idx, m_uint_star_type);
   }
 
-  bool Update() override {
+  lldb::ChildCacheState Update() override {
     m_impl.Clear();
 
     auto type_system = m_backend.GetCompilerType().GetTypeSystem();
     if (!type_system)
-      return false;
+      return lldb::ChildCacheState::eRefetch;
 
     auto ast = ScratchTypeSystemClang::GetForTarget(
         *m_backend.GetExecutionContextRef().GetTargetSP());
     if (!ast)
-      return false;
+      return lldb::ChildCacheState::eRefetch;
 
     m_uint_star_type = ast->GetPointerSizedIntType(false);
 
@@ -65,18 +65,18 @@ class NSIndexPathSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
 
     ProcessSP process_sp = m_backend.GetProcessSP();
     if (!process_sp)
-      return false;
+      return lldb::ChildCacheState::eRefetch;
 
     ObjCLanguageRuntime *runtime = ObjCLanguageRuntime::Get(*process_sp);
 
     if (!runtime)
-      return false;
+      return lldb::ChildCacheState::eRefetch;
 
     ObjCLanguageRuntime::ClassDescriptorSP descriptor(
         runtime->GetClassDescriptor(m_backend));
 
     if (!descriptor.get() || !descriptor->IsValid())
-      return false;
+      return lldb::ChildCacheState::eRefetch;
 
     uint64_t info_bits(0), value_bits(0), payload(0);
 
@@ -119,7 +119,7 @@ class NSIndexPathSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
         }
       }
     }
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   }
 
   bool MightHaveChildren() override { return m_impl.m_mode != Mode::Invalid; }

diff --git a/lldb/source/Plugins/Language/ObjC/NSSet.cpp b/lldb/source/Plugins/Language/ObjC/NSSet.cpp
@@ -50,7 +50,7 @@ class NSSetISyntheticFrontEnd : public SyntheticChildrenFrontEnd {
 
   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
 
-  bool Update() override;
+  lldb::ChildCacheState Update() override;
 
   bool MightHaveChildren() override;
 
@@ -88,7 +88,7 @@ class NSCFSetSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
 
   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
 
-  bool Update() override;
+  lldb::ChildCacheState Update() override;
 
   bool MightHaveChildren() override;
 
@@ -121,7 +121,7 @@ class GenericNSSetMSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
 
   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
 
-  bool Update() override;
+  lldb::ChildCacheState Update() override;
 
   bool MightHaveChildren() override;
 
@@ -237,7 +237,7 @@ class NSSetCodeRunningSyntheticFrontEnd : public SyntheticChildrenFrontEnd {
 
   lldb::ValueObjectSP GetChildAtIndex(size_t idx) override;
 
-  bool Update() override;
+  lldb::ChildCacheState Update() override;
 
   bool MightHaveChildren() override;
 
@@ -426,7 +426,8 @@ lldb_private::formatters::NSSetISyntheticFrontEnd::CalculateNumChildren() {
   return (m_data_32 ? m_data_32->_used : m_data_64->_used);
 }
 
-bool lldb_private::formatters::NSSetISyntheticFrontEnd::Update() {
+lldb::ChildCacheState
+lldb_private::formatters::NSSetISyntheticFrontEnd::Update() {
   m_children.clear();
   delete m_data_32;
   m_data_32 = nullptr;
@@ -435,13 +436,13 @@ bool lldb_private::formatters::NSSetISyntheticFrontEnd::Update() {
   m_ptr_size = 0;
   ValueObjectSP valobj_sp = m_backend.GetSP();
   if (!valobj_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   if (!valobj_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   m_exe_ctx_ref = valobj_sp->GetExecutionContextRef();
   lldb::ProcessSP process_sp(valobj_sp->GetProcessSP());
   if (!process_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   m_ptr_size = process_sp->GetAddressByteSize();
   uint64_t data_location = valobj_sp->GetValueAsUnsigned(0) + m_ptr_size;
   Status error;
@@ -455,9 +456,9 @@ bool lldb_private::formatters::NSSetISyntheticFrontEnd::Update() {
                            error);
   }
   if (error.Fail())
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   m_data_ptr = data_location + m_ptr_size;
-  return true;
+  return lldb::ChildCacheState::eReuse;
 }
 
 bool lldb_private::formatters::NSSetISyntheticFrontEnd::MightHaveChildren() {
@@ -561,20 +562,23 @@ lldb_private::formatters::NSCFSetSyntheticFrontEnd::CalculateNumChildren() {
   return m_hashtable.GetCount();
 }
 
-bool lldb_private::formatters::NSCFSetSyntheticFrontEnd::Update() {
+lldb::ChildCacheState
+lldb_private::formatters::NSCFSetSyntheticFrontEnd::Update() {
   m_children.clear();
   ValueObjectSP valobj_sp = m_backend.GetSP();
   m_ptr_size = 0;
   if (!valobj_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   m_exe_ctx_ref = valobj_sp->GetExecutionContextRef();
 
   lldb::ProcessSP process_sp(valobj_sp->GetProcessSP());
   if (!process_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   m_ptr_size = process_sp->GetAddressByteSize();
   m_order = process_sp->GetByteOrder();
-  return m_hashtable.Update(valobj_sp->GetValueAsUnsigned(0), m_exe_ctx_ref);
+  return m_hashtable.Update(valobj_sp->GetValueAsUnsigned(0), m_exe_ctx_ref)
+             ? lldb::ChildCacheState::eReuse
+             : lldb::ChildCacheState::eRefetch;
 }
 
 bool lldb_private::formatters::NSCFSetSyntheticFrontEnd::MightHaveChildren() {
@@ -701,9 +705,8 @@ lldb_private::formatters::
 }
 
 template <typename D32, typename D64>
-bool
-lldb_private::formatters::
-  GenericNSSetMSyntheticFrontEnd<D32, D64>::Update() {
+lldb::ChildCacheState
+lldb_private::formatters::GenericNSSetMSyntheticFrontEnd<D32, D64>::Update() {
   m_children.clear();
   ValueObjectSP valobj_sp = m_backend.GetSP();
   m_ptr_size = 0;
@@ -712,13 +715,13 @@ lldb_private::formatters::
   delete m_data_64;
   m_data_64 = nullptr;
   if (!valobj_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   if (!valobj_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   m_exe_ctx_ref = valobj_sp->GetExecutionContextRef();
   lldb::ProcessSP process_sp(valobj_sp->GetProcessSP());
   if (!process_sp)
-    return false;
+    return lldb::ChildCacheState::eRefetch;
   m_ptr_size = process_sp->GetAddressByteSize();
   uint64_t data_location = valobj_sp->GetValueAsUnsigned(0) + m_ptr_size;
   Status error;
@@ -731,7 +734,8 @@ lldb_private::formatters::
     process_sp->ReadMemory(data_location, m_data_64, sizeof(D64),
                            error);
   }
-  return error.Success();
+  return error.Success() ? lldb::ChildCacheState::eReuse
+                         : lldb::ChildCacheState::eRefetch;
 }
 
 template <typename D32, typename D64>

diff --git a/lldb/source/Plugins/SymbolVendor/MacOSX/SymbolVendorMacOSX.cpp b/lldb/source/Plugins/SymbolVendor/MacOSX/SymbolVendorMacOSX.cpp
@@ -118,7 +118,13 @@ SymbolVendorMacOSX::CreateInstance(const lldb::ModuleSP &module_sp,
     FileSpec dsym_fspec(module_sp->GetSymbolFileFileSpec());
 
     ObjectFileSP dsym_objfile_sp;
-    if (!dsym_fspec) {
+    // On Darwin, we store the debug information either in object files,
+    // using the debug map to tie them to the executable, or in a dSYM.  We
+    // pass through this routine both for binaries and for .o files, but in the
+    // latter case there will never be an external debug file.  So we shouldn't
+    // do all the stats needed to find it.
+    if (!dsym_fspec && module_sp->GetObjectFile()->CalculateType() !=
+        ObjectFile::eTypeObjectFile) {
       // No symbol file was specified in the module, lets try and find one
       // ourselves.
       FileSpec file_spec = obj_file->GetFileSpec();

diff --git a/lldb/tools/debugserver/source/RNBRemote.cpp b/lldb/tools/debugserver/source/RNBRemote.cpp
@@ -3575,8 +3575,6 @@ rnb_err_t RNBRemote::HandlePacket_qSupported(const char *p) {
 
   if (enable_compression) {
     reply << "SupportedCompressions=lzfse,zlib-deflate,lz4,lzma;";
-    reply << "DefaultCompressionMinSize=" << std::dec << m_compression_minsize
-          << ";";
   }
 
 #if (defined(__arm64__) || defined(__aarch64__))
@@ -4482,46 +4480,25 @@ rnb_err_t RNBRemote::HandlePacket_SetEnableAsyncProfiling(const char *p) {
   return SendPacket("OK");
 }
 
-// QEnableCompression:type:<COMPRESSION-TYPE>;minsize:<MINIMUM PACKET SIZE TO
-// COMPRESS>;
+// QEnableCompression:type:<COMPRESSION-TYPE>;
 //
 // type: must be a type previously reported by the qXfer:features:
 // SupportedCompressions list
-//
-// minsize: is optional; by default the qXfer:features:
-// DefaultCompressionMinSize value is used
-// debugserver may have a better idea of what a good minimum packet size to
-// compress is than lldb.
 
 rnb_err_t RNBRemote::HandlePacket_QEnableCompression(const char *p) {
   p += sizeof("QEnableCompression:") - 1;
 
-  size_t new_compression_minsize = m_compression_minsize;
-  const char *new_compression_minsize_str = strstr(p, "minsize:");
-  if (new_compression_minsize_str) {
-    new_compression_minsize_str += strlen("minsize:");
-    errno = 0;
-    new_compression_minsize = strtoul(new_compression_minsize_str, NULL, 10);
-    if (errno != 0 || new_compression_minsize == ULONG_MAX) {
-      new_compression_minsize = m_compression_minsize;
-    }
-  }
-
   if (strstr(p, "type:zlib-deflate;") != nullptr) {
     EnableCompressionNextSendPacket(compression_types::zlib_deflate);
-    m_compression_minsize = new_compression_minsize;
     return SendPacket("OK");
   } else if (strstr(p, "type:lz4;") != nullptr) {
     EnableCompressionNextSendPacket(compression_types::lz4);
-    m_compression_minsize = new_compression_minsize;
     return SendPacket("OK");
   } else if (strstr(p, "type:lzma;") != nullptr) {
     EnableCompressionNextSendPacket(compression_types::lzma);
-    m_compression_minsize = new_compression_minsize;
     return SendPacket("OK");
   } else if (strstr(p, "type:lzfse;") != nullptr) {
     EnableCompressionNextSendPacket(compression_types::lzfse);
-    m_compression_minsize = new_compression_minsize;
     return SendPacket("OK");
   }
 

diff --git a/llvm/include/llvm/Analysis/ValueTracking.h b/llvm/include/llvm/Analysis/ValueTracking.h
@@ -248,6 +248,10 @@ struct KnownFPClass {
   /// definitely set or false if the sign bit is definitely unset.
   std::optional<bool> SignBit;
 
+  bool operator==(KnownFPClass Other) const {
+    return KnownFPClasses == Other.KnownFPClasses && SignBit == Other.SignBit;
+  }
+
   /// Return true if it's known this can never be one of the mask entries.
   bool isKnownNever(FPClassTest Mask) const {
     return (KnownFPClasses & Mask) == fcNone;

diff --git a/llvm/include/llvm/CodeGen/GlobalISel/Utils.h b/llvm/include/llvm/CodeGen/GlobalISel/Utils.h
@@ -368,7 +368,10 @@ LLT getCoverTy(LLT OrigTy, LLT TargetTy);
 /// If these are vectors with different element types, this will try to produce
 /// a vector with a compatible total size, but the element type of \p OrigTy. If
 /// this can't be satisfied, this will produce a scalar smaller than the
-/// original vector elements.
+/// original vector elements. It is an error to call this function where
+/// one argument is a fixed vector and the other is a scalable vector, since it
+/// is illegal to build a G_{MERGE|UNMERGE}_VALUES between fixed and scalable
+/// vectors.
 ///
 /// In the worst case, this returns LLT::scalar(1)
 LLVM_READNONE

diff --git a/llvm/include/llvm/CodeGen/MachineFunction.h b/llvm/include/llvm/CodeGen/MachineFunction.h
@@ -1423,9 +1423,7 @@ template <> struct GraphTraits<Inverse<const MachineFunction*>> :
   }
 };
 
-class MachineFunctionAnalysisManager;
-void verifyMachineFunction(MachineFunctionAnalysisManager *,
-                           const std::string &Banner,
+void verifyMachineFunction(const std::string &Banner,
                            const MachineFunction &MF);
 
 } // end namespace llvm

diff --git a/llvm/include/llvm/CodeGen/MachineModuleInfo.h b/llvm/include/llvm/CodeGen/MachineModuleInfo.h
@@ -192,12 +192,6 @@ class MachineModuleInfo {
   unsigned getCurrentCallSite() { return CurCallSite; }
 
   /// \}
-
-  // MMI owes MCContext. It should never be invalidated.
-  bool invalidate(Module &, const PreservedAnalyses &,
-                  ModuleAnalysisManager::Invalidator &) {
-    return false;
-  }
 }; // End class MachineModuleInfo
 
 class MachineModuleInfoWrapperPass : public ImmutablePass {
@@ -218,21 +212,37 @@ class MachineModuleInfoWrapperPass : public ImmutablePass {
   const MachineModuleInfo &getMMI() const { return MMI; }
 };
 
-/// An analysis that produces \c MachineInfo for a module.
+/// An analysis that produces \c MachineModuleInfo for a module.
+/// This does not produce its own MachineModuleInfo because we need a consistent
+/// MachineModuleInfo to keep ownership of MachineFunctions regardless of
+/// analysis invalidation/clearing. So something outside the analysis
+/// infrastructure must own the MachineModuleInfo.
 class MachineModuleAnalysis : public AnalysisInfoMixin<MachineModuleAnalysis> {
   friend AnalysisInfoMixin<MachineModuleAnalysis>;
   static AnalysisKey Key;
 
-  const LLVMTargetMachine *TM;
+  MachineModuleInfo &MMI;
 
 public:
-  /// Provide the result type for this analysis pass.
-  using Result = MachineModuleInfo;
+  class Result {
+    MachineModuleInfo &MMI;
+    Result(MachineModuleInfo &MMI) : MMI(MMI) {}
+    friend class MachineModuleAnalysis;
+
+  public:
+    MachineModuleInfo &getMMI() { return MMI; }
+
+    // MMI owes MCContext. It should never be invalidated.
+    bool invalidate(Module &, const PreservedAnalyses &,
+                    ModuleAnalysisManager::Invalidator &) {
+      return false;
+    }
+  };
 
-  MachineModuleAnalysis(const LLVMTargetMachine *TM) : TM(TM) {}
+  MachineModuleAnalysis(MachineModuleInfo &MMI) : MMI(MMI) {}
 
   /// Run the analysis pass and produce machine module information.
-  MachineModuleInfo run(Module &M, ModuleAnalysisManager &);
+  Result run(Module &M, ModuleAnalysisManager &);
 };
 
 } // end namespace llvm

diff --git a/llvm/include/llvm/CodeGen/Register.h b/llvm/include/llvm/CodeGen/Register.h
@@ -36,7 +36,7 @@ class Register {
   static_assert(std::numeric_limits<decltype(Reg)>::max() >= 0xFFFFFFFF,
                 "Reg isn't large enough to hold full range.");
 
-  /// isStackSlot - Sometimes it is useful the be able to store a non-negative
+  /// isStackSlot - Sometimes it is useful to be able to store a non-negative
   /// frame index in a variable that normally holds a register. isStackSlot()
   /// returns true if Reg is in the range used for stack slots.
   ///

diff --git a/llvm/include/llvm/CodeGen/SelectionDAG.h b/llvm/include/llvm/CodeGen/SelectionDAG.h
@@ -1613,10 +1613,10 @@ class SelectionDAG {
   /// Expand the specified \c ISD::VACOPY node as the Legalize pass would.
   SDValue expandVACopy(SDNode *Node);
 
-  /// Returs an GlobalAddress of the function from the current module with
+  /// Return a GlobalAddress of the function from the current module with
   /// name matching the given ExternalSymbol. Additionally can provide the
   /// matched function.
-  /// Panics the function doesn't exists.
+  /// Panic if the function doesn't exist.
   SDValue getSymbolFunctionGlobalAddress(SDValue Op,
                                          Function **TargetFunction = nullptr);
 
@@ -2255,7 +2255,7 @@ class SelectionDAG {
   std::pair<EVT, EVT> GetDependentSplitDestVTs(const EVT &VT, const EVT &EnvVT,
                                                bool *HiIsEmpty) const;
 
-  /// Split the vector with EXTRACT_SUBVECTOR using the provides
+  /// Split the vector with EXTRACT_SUBVECTOR using the provided
   /// VTs and return the low/high part.
   std::pair<SDValue, SDValue> SplitVector(const SDValue &N, const SDLoc &DL,
                                           const EVT &LoVT, const EVT &HiVT);

diff --git a/llvm/include/llvm/Frontend/Offloading/OffloadWrapper.h b/llvm/include/llvm/Frontend/Offloading/OffloadWrapper.h
@@ -20,10 +20,13 @@ using EntryArrayTy = std::pair<GlobalVariable *, GlobalVariable *>;
 /// \param EntryArray Optional pair pointing to the `__start` and `__stop`
 /// symbols holding the `__tgt_offload_entry` array.
 /// \param Suffix An optional suffix appended to the emitted symbols.
+/// \param Relocatable Indicate if we need to change the offloading section to
+/// create a relocatable object.
 llvm::Error wrapOpenMPBinaries(llvm::Module &M,
                                llvm::ArrayRef<llvm::ArrayRef<char>> Images,
                                EntryArrayTy EntryArray,
-                               llvm::StringRef Suffix = "");
+                               llvm::StringRef Suffix = "",
+                               bool Relocatable = false);
 
 /// Wraps the input fatbinary image into the module \p M as global symbols and
 /// registers the images with the CUDA runtime.

diff --git a/llvm/include/llvm/IR/ModuleSummaryIndex.h b/llvm/include/llvm/IR/ModuleSummaryIndex.h
@@ -1377,7 +1377,7 @@ class ModuleSummaryIndex {
 
   // Temporary map while building StackIds list. Clear when index is completely
   // built via releaseTemporaryMemory.
-  std::map<uint64_t, unsigned> StackIdToIndex;
+  DenseMap<uint64_t, unsigned> StackIdToIndex;
 
   // YAML I/O support.
   friend yaml::MappingTraits<ModuleSummaryIndex>;

diff --git a/llvm/include/llvm/IR/PatternMatch.h b/llvm/include/llvm/IR/PatternMatch.h
@@ -1711,6 +1711,34 @@ m_BitCast(const OpTy &Op) {
   return CastOperator_match<OpTy, Instruction::BitCast>(Op);
 }
 
+template <typename Op_t> struct ElementWiseBitCast_match {
+  Op_t Op;
+
+  ElementWiseBitCast_match(const Op_t &OpMatch) : Op(OpMatch) {}
+
+  template <typename OpTy> bool match(OpTy *V) {
+    BitCastInst *I = dyn_cast<BitCastInst>(V);
+    if (!I)
+      return false;
+    Type *SrcType = I->getSrcTy();
+    Type *DstType = I->getType();
+    // Make sure the bitcast doesn't change between scalar and vector and
+    // doesn't change the number of vector elements.
+    if (SrcType->isVectorTy() != DstType->isVectorTy())
+      return false;
+    if (VectorType *SrcVecTy = dyn_cast<VectorType>(SrcType);
+        SrcVecTy && SrcVecTy->getElementCount() !=
+                        cast<VectorType>(DstType)->getElementCount())
+      return false;
+    return Op.match(I->getOperand(0));
+  }
+};
+
+template <typename OpTy>
+inline ElementWiseBitCast_match<OpTy> m_ElementWiseBitCast(const OpTy &Op) {
+  return ElementWiseBitCast_match<OpTy>(Op);
+}
+
 /// Matches PtrToInt.
 template <typename OpTy>
 inline CastOperator_match<OpTy, Instruction::PtrToInt>

diff --git a/llvm/include/llvm/ProfileData/InstrProf.h b/llvm/include/llvm/ProfileData/InstrProf.h
@@ -195,7 +195,7 @@ std::string getIRPGOFuncName(const Function &F, bool InLTO = false);
 
 /// \return the filename and the function name parsed from the output of
 /// \c getIRPGOFuncName()
-std::pair<StringRef, StringRef> getParsedIRPGOFuncName(StringRef IRPGOFuncName);
+std::pair<StringRef, StringRef> getParsedIRPGOName(StringRef IRPGOName);
 
 /// Return the name of the global variable used to store a function
 /// name in PGO instrumentation. \c FuncName is the IRPGO function name

diff --git a/llvm/include/llvm/Support/AMDGPUMetadata.h b/llvm/include/llvm/Support/AMDGPUMetadata.h
@@ -47,7 +47,7 @@ constexpr uint32_t VersionMinorV5 = 2;
 /// HSA metadata major version for code object V6.
 constexpr uint32_t VersionMajorV6 = 1;
 /// HSA metadata minor version for code object V6.
-constexpr uint32_t VersionMinorV6 = 3;
+constexpr uint32_t VersionMinorV6 = 2;
 
 /// Old HSA metadata beginning assembler directive for V2. This is only used for
 /// diagnostics now.

diff --git a/llvm/lib/Analysis/BasicAliasAnalysis.cpp b/llvm/lib/Analysis/BasicAliasAnalysis.cpp
@@ -1170,6 +1170,27 @@ AliasResult BasicAAResult::aliasGEP(
     }
   }
 
+  // VScale Alias Analysis - Given one scalable offset between accesses and a
+  // scalable typesize, we can divide each side by vscale, treating both values
+  // as a constant. We prove that Offset/vscale >= TypeSize/vscale.
+  if (DecompGEP1.VarIndices.size() == 1 && DecompGEP1.VarIndices[0].IsNSW &&
+      DecompGEP1.VarIndices[0].Val.TruncBits == 0 &&
+      DecompGEP1.Offset.isZero() &&
+      PatternMatch::match(DecompGEP1.VarIndices[0].Val.V,
+                          PatternMatch::m_VScale())) {
+    const VariableGEPIndex &ScalableVar = DecompGEP1.VarIndices[0];
+    APInt Scale =
+        ScalableVar.IsNegated ? -ScalableVar.Scale : ScalableVar.Scale;
+    LocationSize VLeftSize = Scale.isNegative() ? V1Size : V2Size;
+
+    // Note that we do not check that the typesize is scalable, as vscale >= 1
+    // so noalias still holds so long as the dependency distance is at least as
+    // big as the typesize.
+    if (VLeftSize.hasValue() &&
+        Scale.uge(VLeftSize.getValue().getKnownMinValue()))
+      return AliasResult::NoAlias;
+  }
+
   // Bail on analysing scalable LocationSize
   if (V1Size.isScalable() || V2Size.isScalable())
     return AliasResult::MayAlias;

diff --git a/llvm/lib/Analysis/DomConditionCache.cpp b/llvm/lib/Analysis/DomConditionCache.cpp
@@ -34,23 +34,39 @@ static void findAffectedValues(Value *Cond,
     }
   };
 
-  ICmpInst::Predicate Pred;
-  Value *A;
-  if (match(Cond, m_ICmp(Pred, m_Value(A), m_Constant()))) {
-    AddAffected(A);
+  bool TopLevelIsAnd = match(Cond, m_LogicalAnd());
+  SmallVector<Value *, 8> Worklist;
+  SmallPtrSet<Value *, 8> Visited;
+  Worklist.push_back(Cond);
+  while (!Worklist.empty()) {
+    Value *V = Worklist.pop_back_val();
+    if (!Visited.insert(V).second)
+      continue;
 
-    if (ICmpInst::isEquality(Pred)) {
-      Value *X;
-      // (X & C) or (X | C) or (X ^ C).
-      // (X << C) or (X >>_s C) or (X >>_u C).
-      if (match(A, m_BitwiseLogic(m_Value(X), m_ConstantInt())) ||
-          match(A, m_Shift(m_Value(X), m_ConstantInt())))
-        AddAffected(X);
-    } else {
-      Value *X;
-      // Handle (A + C1) u< C2, which is the canonical form of A > C3 && A < C4.
-      if (match(A, m_Add(m_Value(X), m_ConstantInt())))
-        AddAffected(X);
+    ICmpInst::Predicate Pred;
+    Value *A, *B;
+    // Only recurse into and/or if it matches the top-level and/or type.
+    if (TopLevelIsAnd ? match(V, m_LogicalAnd(m_Value(A), m_Value(B)))
+                      : match(V, m_LogicalOr(m_Value(A), m_Value(B)))) {
+      Worklist.push_back(A);
+      Worklist.push_back(B);
+    } else if (match(V, m_ICmp(Pred, m_Value(A), m_Constant()))) {
+      AddAffected(A);
+
+      if (ICmpInst::isEquality(Pred)) {
+        Value *X;
+        // (X & C) or (X | C) or (X ^ C).
+        // (X << C) or (X >>_s C) or (X >>_u C).
+        if (match(A, m_BitwiseLogic(m_Value(X), m_ConstantInt())) ||
+            match(A, m_Shift(m_Value(X), m_ConstantInt())))
+          AddAffected(X);
+      } else {
+        Value *X;
+        // Handle (A + C1) u< C2, which is the canonical form of
+        // A > C3 && A < C4.
+        if (match(A, m_Add(m_Value(X), m_ConstantInt())))
+          AddAffected(X);
+      }
     }
   }
 }

diff --git a/llvm/lib/Analysis/InstructionSimplify.cpp b/llvm/lib/Analysis/InstructionSimplify.cpp
@@ -1853,35 +1853,36 @@ static Value *simplifyAndOrOfFCmps(const SimplifyQuery &Q, FCmpInst *LHS,
     return nullptr;
 
   FCmpInst::Predicate PredL = LHS->getPredicate(), PredR = RHS->getPredicate();
-  if ((PredL == FCmpInst::FCMP_ORD && PredR == FCmpInst::FCMP_ORD && IsAnd) ||
-      (PredL == FCmpInst::FCMP_UNO && PredR == FCmpInst::FCMP_UNO && !IsAnd)) {
-    // (fcmp ord NNAN, X) & (fcmp ord X, Y) --> fcmp ord X, Y
-    // (fcmp ord NNAN, X) & (fcmp ord Y, X) --> fcmp ord Y, X
-    // (fcmp ord X, NNAN) & (fcmp ord X, Y) --> fcmp ord X, Y
-    // (fcmp ord X, NNAN) & (fcmp ord Y, X) --> fcmp ord Y, X
-    // (fcmp uno NNAN, X) | (fcmp uno X, Y) --> fcmp uno X, Y
-    // (fcmp uno NNAN, X) | (fcmp uno Y, X) --> fcmp uno Y, X
-    // (fcmp uno X, NNAN) | (fcmp uno X, Y) --> fcmp uno X, Y
-    // (fcmp uno X, NNAN) | (fcmp uno Y, X) --> fcmp uno Y, X
+  if ((PredL == FCmpInst::FCMP_ORD || PredL == FCmpInst::FCMP_UNO) &&
+      ((FCmpInst::isOrdered(PredR) && IsAnd) ||
+       (FCmpInst::isUnordered(PredR) && !IsAnd))) {
+    // (fcmp ord X, NNAN) & (fcmp o** X, Y) --> fcmp o** X, Y
+    // (fcmp uno X, NNAN) & (fcmp o** X, Y) --> false
+    // (fcmp uno X, NNAN) | (fcmp u** X, Y) --> fcmp u** X, Y
+    // (fcmp ord X, NNAN) | (fcmp u** X, Y) --> true
     if (((LHS1 == RHS0 || LHS1 == RHS1) &&
          isKnownNeverNaN(LHS0, /*Depth=*/0, Q)) ||
         ((LHS0 == RHS0 || LHS0 == RHS1) &&
          isKnownNeverNaN(LHS1, /*Depth=*/0, Q)))
-      return RHS;
-
-    // (fcmp ord X, Y) & (fcmp ord NNAN, X) --> fcmp ord X, Y
-    // (fcmp ord Y, X) & (fcmp ord NNAN, X) --> fcmp ord Y, X
-    // (fcmp ord X, Y) & (fcmp ord X, NNAN) --> fcmp ord X, Y
-    // (fcmp ord Y, X) & (fcmp ord X, NNAN) --> fcmp ord Y, X
-    // (fcmp uno X, Y) | (fcmp uno NNAN, X) --> fcmp uno X, Y
-    // (fcmp uno Y, X) | (fcmp uno NNAN, X) --> fcmp uno Y, X
-    // (fcmp uno X, Y) | (fcmp uno X, NNAN) --> fcmp uno X, Y
-    // (fcmp uno Y, X) | (fcmp uno X, NNAN) --> fcmp uno Y, X
+      return FCmpInst::isOrdered(PredL) == FCmpInst::isOrdered(PredR)
+                 ? static_cast<Value *>(RHS)
+                 : ConstantInt::getBool(LHS->getType(), !IsAnd);
+  }
+
+  if ((PredR == FCmpInst::FCMP_ORD || PredR == FCmpInst::FCMP_UNO) &&
+      ((FCmpInst::isOrdered(PredL) && IsAnd) ||
+       (FCmpInst::isUnordered(PredL) && !IsAnd))) {
+    // (fcmp o** X, Y) & (fcmp ord X, NNAN) --> fcmp o** X, Y
+    // (fcmp o** X, Y) & (fcmp uno X, NNAN) --> false
+    // (fcmp u** X, Y) | (fcmp uno X, NNAN) --> fcmp u** X, Y
+    // (fcmp u** X, Y) | (fcmp ord X, NNAN) --> true
     if (((RHS1 == LHS0 || RHS1 == LHS1) &&
          isKnownNeverNaN(RHS0, /*Depth=*/0, Q)) ||
         ((RHS0 == LHS0 || RHS0 == LHS1) &&
          isKnownNeverNaN(RHS1, /*Depth=*/0, Q)))
-      return LHS;
+      return FCmpInst::isOrdered(PredL) == FCmpInst::isOrdered(PredR)
+                 ? static_cast<Value *>(LHS)
+                 : ConstantInt::getBool(LHS->getType(), !IsAnd);
   }
 
   return nullptr;
@@ -3034,7 +3035,7 @@ static Value *simplifyICmpWithConstant(CmpInst::Predicate Pred, Value *LHS,
   // floating-point casts:
   // icmp slt (bitcast (uitofp X)),  0 --> false
   // icmp sgt (bitcast (uitofp X)), -1 --> true
-  if (match(LHS, m_BitCast(m_UIToFP(m_Value(X))))) {
+  if (match(LHS, m_ElementWiseBitCast(m_UIToFP(m_Value(X))))) {
     if (Pred == ICmpInst::ICMP_SLT && match(RHS, m_Zero()))
       return ConstantInt::getFalse(ITy);
     if (Pred == ICmpInst::ICMP_SGT && match(RHS, m_AllOnes()))

diff --git a/llvm/lib/Analysis/ValueTracking.cpp b/llvm/lib/Analysis/ValueTracking.cpp
@@ -706,28 +706,40 @@ static void computeKnownBitsFromCmp(const Value *V, CmpInst::Predicate Pred,
   }
 }
 
+static void computeKnownBitsFromCond(const Value *V, Value *Cond,
+                                     KnownBits &Known, unsigned Depth,
+                                     const SimplifyQuery &SQ, bool Invert) {
+  Value *A, *B;
+  if (Depth < MaxAnalysisRecursionDepth &&
+      (Invert ? match(Cond, m_LogicalOr(m_Value(A), m_Value(B)))
+              : match(Cond, m_LogicalAnd(m_Value(A), m_Value(B))))) {
+    computeKnownBitsFromCond(V, A, Known, Depth + 1, SQ, Invert);
+    computeKnownBitsFromCond(V, B, Known, Depth + 1, SQ, Invert);
+  }
+
+  if (auto *Cmp = dyn_cast<ICmpInst>(Cond))
+    computeKnownBitsFromCmp(
+        V, Invert ? Cmp->getInversePredicate() : Cmp->getPredicate(),
+        Cmp->getOperand(0), Cmp->getOperand(1), Known, SQ);
+}
+
 void llvm::computeKnownBitsFromContext(const Value *V, KnownBits &Known,
-                                      unsigned Depth, const SimplifyQuery &Q) {
+                                       unsigned Depth, const SimplifyQuery &Q) {
   if (!Q.CxtI)
     return;
 
   if (Q.DC && Q.DT) {
     // Handle dominating conditions.
     for (BranchInst *BI : Q.DC->conditionsFor(V)) {
-      auto *Cmp = dyn_cast<ICmpInst>(BI->getCondition());
-      if (!Cmp)
-        continue;
-
       BasicBlockEdge Edge0(BI->getParent(), BI->getSuccessor(0));
       if (Q.DT->dominates(Edge0, Q.CxtI->getParent()))
-        computeKnownBitsFromCmp(V, Cmp->getPredicate(), Cmp->getOperand(0),
-                                Cmp->getOperand(1), Known, Q);
+        computeKnownBitsFromCond(V, BI->getCondition(), Known, Depth, Q,
+                                 /*Invert*/ false);
 
       BasicBlockEdge Edge1(BI->getParent(), BI->getSuccessor(1));
       if (Q.DT->dominates(Edge1, Q.CxtI->getParent()))
-        computeKnownBitsFromCmp(V, Cmp->getInversePredicate(),
-                                Cmp->getOperand(0), Cmp->getOperand(1), Known,
-                                Q);
+        computeKnownBitsFromCond(V, BI->getCondition(), Known, Depth, Q,
+                                 /*Invert*/ true);
     }
 
     if (Known.hasConflict())

diff --git a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
@@ -6632,9 +6632,6 @@ Error BitcodeReader::materialize(GlobalValue *GV) {
   if (Error Err = materializeMetadata())
     return Err;
 
-  bool NewDebugInfoRequested = F->IsNewDbgInfoFormat;
-  F->IsNewDbgInfoFormat = false;
-
   // Move the bit stream to the saved position of the deferred function body.
   if (Error JumpFailed = Stream.JumpToBit(DFII->second))
     return JumpFailed;
@@ -6710,14 +6707,6 @@ Error BitcodeReader::materialize(GlobalValue *GV) {
   // Look for functions that rely on old function attribute behavior.
   UpgradeFunctionAttributes(*F);
 
-  // If we've materialized a function set up in "new" debug-info mode, the
-  // contents just loaded will still be in dbg.value mode. Switch to the new
-  // mode now. NB: we can add more complicated logic here in the future to
-  // correctly identify when we do and don't need to autoupgrade.
-  if (NewDebugInfoRequested) {
-    F->convertToNewDbgValues();
-  }
-
   // Bring in any functions that this function forward-referenced via
   // blockaddresses.
   return materializeForwardReferencedFunctions();
@@ -8042,14 +8031,6 @@ BitcodeModule::getModuleImpl(LLVMContext &Context, bool MaterializeAll,
       return std::move(Err);
   }
 
-  // If we are operating in a "new debug-info" context, upgrade the debug-info
-  // in the loaded module. This is a transitional approach as we enable "new"
-  // debug-info in LLVM, which will eventually be pushed down into the
-  // autoupgrade path once the bitcode-encoding is finalised. Non-materialised
-  // functions will be upgraded in the materialize method.
-  if (UseNewDbgInfoFormat && !M->IsNewDbgInfoFormat)
-    M->convertToNewDbgValues();
-
   return std::move(M);
 }
 

diff --git a/llvm/lib/CodeGen/AtomicExpandPass.cpp b/llvm/lib/CodeGen/AtomicExpandPass.cpp
@@ -322,16 +322,6 @@ bool AtomicExpand::runOnFunction(Function &F) {
       if (isIdempotentRMW(RMWI) && simplifyIdempotentRMW(RMWI)) {
         MadeChange = true;
       } else {
-        AtomicRMWInst::BinOp Op = RMWI->getOperation();
-        unsigned MinCASSize = TLI->getMinCmpXchgSizeInBits() / 8;
-        unsigned ValueSize = getAtomicOpSize(RMWI);
-        if (ValueSize < MinCASSize &&
-            (Op == AtomicRMWInst::Or || Op == AtomicRMWInst::Xor ||
-             Op == AtomicRMWInst::And)) {
-          RMWI = widenPartwordAtomicRMW(RMWI);
-          MadeChange = true;
-        }
-
         MadeChange |= tryExpandAtomicRMW(RMWI);
       }
     } else if (CASI)
@@ -607,6 +597,17 @@ bool AtomicExpand::tryExpandAtomicRMW(AtomicRMWInst *AI) {
     return true;
   }
   case TargetLoweringBase::AtomicExpansionKind::MaskedIntrinsic: {
+    unsigned MinCASSize = TLI->getMinCmpXchgSizeInBits() / 8;
+    unsigned ValueSize = getAtomicOpSize(AI);
+    if (ValueSize < MinCASSize) {
+      AtomicRMWInst::BinOp Op = AI->getOperation();
+      // Widen And/Or/Xor and give the target another chance at expanding it.
+      if (Op == AtomicRMWInst::Or || Op == AtomicRMWInst::Xor ||
+          Op == AtomicRMWInst::And) {
+        tryExpandAtomicRMW(widenPartwordAtomicRMW(AI));
+        return true;
+      }
+    }
     expandAtomicRMWToMaskedIntrinsic(AI);
     return true;
   }
@@ -845,6 +846,14 @@ static Value *performMaskedAtomicOp(AtomicRMWInst::BinOp Op,
 /// part of the value.
 void AtomicExpand::expandPartwordAtomicRMW(
     AtomicRMWInst *AI, TargetLoweringBase::AtomicExpansionKind ExpansionKind) {
+  // Widen And/Or/Xor and give the target another chance at expanding it.
+  AtomicRMWInst::BinOp Op = AI->getOperation();
+  if (Op == AtomicRMWInst::Or || Op == AtomicRMWInst::Xor ||
+      Op == AtomicRMWInst::And) {
+    tryExpandAtomicRMW(widenPartwordAtomicRMW(AI));
+    return;
+  }
+
   AtomicOrdering MemOpOrder = AI->getOrdering();
   SyncScope::ID SSID = AI->getSyncScopeID();
 
@@ -855,18 +864,16 @@ void AtomicExpand::expandPartwordAtomicRMW(
                        AI->getAlign(), TLI->getMinCmpXchgSizeInBits() / 8);
 
   Value *ValOperand_Shifted = nullptr;
-  if (AI->getOperation() == AtomicRMWInst::Xchg ||
-      AI->getOperation() == AtomicRMWInst::Add ||
-      AI->getOperation() == AtomicRMWInst::Sub ||
-      AI->getOperation() == AtomicRMWInst::Nand) {
+  if (Op == AtomicRMWInst::Xchg || Op == AtomicRMWInst::Add ||
+      Op == AtomicRMWInst::Sub || Op == AtomicRMWInst::Nand) {
     ValOperand_Shifted =
         Builder.CreateShl(Builder.CreateZExt(AI->getValOperand(), PMV.WordType),
                           PMV.ShiftAmt, "ValOperand_Shifted");
   }
 
   auto PerformPartwordOp = [&](IRBuilderBase &Builder, Value *Loaded) {
-    return performMaskedAtomicOp(AI->getOperation(), Builder, Loaded,
-                                 ValOperand_Shifted, AI->getValOperand(), PMV);
+    return performMaskedAtomicOp(Op, Builder, Loaded, ValOperand_Shifted,
+                                 AI->getValOperand(), PMV);
   };
 
   Value *OldResult;

diff --git a/llvm/lib/CodeGen/CodeGenPrepare.cpp b/llvm/lib/CodeGen/CodeGenPrepare.cpp
@@ -8455,7 +8455,8 @@ bool CodeGenPrepare::fixupDPValuesOnInst(Instruction &I) {
 // FIXME: should updating debug-info really cause the "changed" flag to fire,
 // which can cause a function to be reprocessed?
 bool CodeGenPrepare::fixupDPValue(DPValue &DPV) {
-  if (DPV.Type != DPValue::LocationType::Value)
+  if (DPV.Type != DPValue::LocationType::Value &&
+      DPV.Type != DPValue::LocationType::Assign)
     return false;
 
   // Does this DPValue refer to a sunk address calculation?

diff --git a/llvm/lib/CodeGen/GlobalISel/IRTranslator.cpp b/llvm/lib/CodeGen/GlobalISel/IRTranslator.cpp
@@ -2120,6 +2120,13 @@ bool IRTranslator::translateKnownIntrinsic(const CallInst &CI, Intrinsic::ID ID,
                                                 ListSize, Alignment));
     return true;
   }
+  case Intrinsic::dbg_assign:
+    // A dbg.assign is a dbg.value with more information about stack locations,
+    // typically produced during optimisation of variables with leaked
+    // addresses. We can treat it like a normal dbg_value intrinsic here; to
+    // benefit from the full analysis of stack/SSA locations, GlobalISel would
+    // need to register for and use the AssignmentTrackingAnalysis pass.
+    LLVM_FALLTHROUGH;
   case Intrinsic::dbg_value: {
     // This form of DBG_VALUE is target-independent.
     const DbgValueInst &DI = cast<DbgValueInst>(CI);

diff --git a/llvm/lib/CodeGen/GlobalISel/Utils.cpp b/llvm/lib/CodeGen/GlobalISel/Utils.cpp
@@ -1159,45 +1159,56 @@ LLT llvm::getCoverTy(LLT OrigTy, LLT TargetTy) {
 }
 
 LLT llvm::getGCDType(LLT OrigTy, LLT TargetTy) {
-  const unsigned OrigSize = OrigTy.getSizeInBits();
-  const unsigned TargetSize = TargetTy.getSizeInBits();
-
-  if (OrigSize == TargetSize)
+  if (OrigTy.getSizeInBits() == TargetTy.getSizeInBits())
     return OrigTy;
 
-  if (OrigTy.isVector()) {
+  if (OrigTy.isVector() && TargetTy.isVector()) {
     LLT OrigElt = OrigTy.getElementType();
-    if (TargetTy.isVector()) {
-      LLT TargetElt = TargetTy.getElementType();
-      if (OrigElt.getSizeInBits() == TargetElt.getSizeInBits()) {
-        int GCD = std::gcd(OrigTy.getNumElements(), TargetTy.getNumElements());
-        return LLT::scalarOrVector(ElementCount::getFixed(GCD), OrigElt);
-      }
-    } else {
-      // If the source is a vector of pointers, return a pointer element.
-      if (OrigElt.getSizeInBits() == TargetSize)
-        return OrigElt;
-    }
 
-    unsigned GCD = std::gcd(OrigSize, TargetSize);
+    // TODO: The docstring for this function says the intention is to use this
+    // function to build MERGE/UNMERGE instructions. It won't be the case that
+    // we generate a MERGE/UNMERGE between fixed and scalable vector types. We
+    // could implement getGCDType between the two in the future if there was a
+    // need, but it is not worth it now as this function should not be used in
+    // that way.
+    assert(((OrigTy.isScalableVector() && !TargetTy.isFixedVector()) ||
+            (OrigTy.isFixedVector() && !TargetTy.isScalableVector())) &&
+           "getGCDType not implemented between fixed and scalable vectors.");
+
+    unsigned GCD = std::gcd(OrigTy.getSizeInBits().getKnownMinValue(),
+                            TargetTy.getSizeInBits().getKnownMinValue());
     if (GCD == OrigElt.getSizeInBits())
-      return OrigElt;
+      return LLT::scalarOrVector(ElementCount::get(1, OrigTy.isScalable()),
+                                 OrigElt);
 
-    // If we can't produce the original element type, we have to use a smaller
-    // scalar.
+    // Cannot produce original element type, but both have vscale in common.
     if (GCD < OrigElt.getSizeInBits())
-      return LLT::scalar(GCD);
-    return LLT::fixed_vector(GCD / OrigElt.getSizeInBits(), OrigElt);
-  }
+      return LLT::scalarOrVector(ElementCount::get(1, OrigTy.isScalable()),
+                                 GCD);
 
-  if (TargetTy.isVector()) {
-    // Try to preserve the original element type.
-    LLT TargetElt = TargetTy.getElementType();
-    if (TargetElt.getSizeInBits() == OrigSize)
-      return OrigTy;
+    return LLT::vector(
+        ElementCount::get(GCD / OrigElt.getSizeInBits().getFixedValue(),
+                          OrigTy.isScalable()),
+        OrigElt);
   }
 
-  unsigned GCD = std::gcd(OrigSize, TargetSize);
+  // If one type is vector and the element size matches the scalar size, then
+  // the gcd is the scalar type.
+  if (OrigTy.isVector() &&
+      OrigTy.getElementType().getSizeInBits() == TargetTy.getSizeInBits())
+    return OrigTy.getElementType();
+  if (TargetTy.isVector() &&
+      TargetTy.getElementType().getSizeInBits() == OrigTy.getSizeInBits())
+    return OrigTy;
+
+  // At this point, both types are either scalars of different type or one is a
+  // vector and one is a scalar. If both types are scalars, the GCD type is the
+  // GCD between the two scalar sizes. If one is vector and one is scalar, then
+  // the GCD type is the GCD between the scalar and the vector element size.
+  LLT OrigScalar = OrigTy.getScalarType();
+  LLT TargetScalar = TargetTy.getScalarType();
+  unsigned GCD = std::gcd(OrigScalar.getSizeInBits().getFixedValue(),
+                          TargetScalar.getSizeInBits().getFixedValue());
   return LLT::scalar(GCD);
 }
 

diff --git a/llvm/lib/CodeGen/MachineModuleInfo.cpp b/llvm/lib/CodeGen/MachineModuleInfo.cpp
@@ -237,11 +237,10 @@ bool MachineModuleInfoWrapperPass::doFinalization(Module &M) {
 
 AnalysisKey MachineModuleAnalysis::Key;
 
-MachineModuleInfo MachineModuleAnalysis::run(Module &M,
-                                             ModuleAnalysisManager &) {
-  MachineModuleInfo MMI(TM);
+MachineModuleAnalysis::Result
+MachineModuleAnalysis::run(Module &M, ModuleAnalysisManager &) {
   MMI.TheModule = &M;
-  MMI.DbgInfoAvailable = !DisableDebugInfoPrinting &&
-                         !M.debug_compile_units().empty();
-  return MMI;
+  MMI.DbgInfoAvailable =
+      !DisableDebugInfoPrinting && !M.debug_compile_units().empty();
+  return Result(MMI);
 }
diff --git a/llvm/lib/CodeGen/MachinePassManager.cpp b/llvm/lib/CodeGen/MachinePassManager.cpp
@@ -29,7 +29,7 @@ Error MachineFunctionPassManager::run(Module &M,
   // because we don't run any module pass in codegen pipeline. This is very
   // important because the codegen state is stored in MMI which is the analysis
   // result of MachineModuleAnalysis. MMI should not be recomputed.
-  auto &MMI = MFAM.getResult<MachineModuleAnalysis>(M);
+  auto &MMI = MFAM.getResult<MachineModuleAnalysis>(M).getMMI();
 
   (void)RequireCodeGenSCCOrder;
   assert(!RequireCodeGenSCCOrder && "not implemented");
@@ -42,12 +42,12 @@ Error MachineFunctionPassManager::run(Module &M,
     // No need to pop this callback later since MIR pipeline is flat which means
     // current pipeline is the top-level pipeline. Callbacks are not used after
     // current pipeline.
-    PI.pushBeforeNonSkippedPassCallback([&MFAM](StringRef PassID, Any IR) {
+    PI.pushBeforeNonSkippedPassCallback([](StringRef PassID, Any IR) {
       assert(llvm::any_cast<const MachineFunction *>(&IR));
       const MachineFunction *MF = llvm::any_cast<const MachineFunction *>(IR);
       assert(MF && "Machine function should be valid for printing");
       std::string Banner = std::string("After ") + std::string(PassID);
-      verifyMachineFunction(&MFAM, Banner, *MF);
+      verifyMachineFunction(Banner, *MF);
     });
   }
 

diff --git a/llvm/lib/CodeGen/MachineVerifier.cpp b/llvm/lib/CodeGen/MachineVerifier.cpp
@@ -339,8 +339,7 @@ FunctionPass *llvm::createMachineVerifierPass(const std::string &Banner) {
   return new MachineVerifierPass(Banner);
 }
 
-void llvm::verifyMachineFunction(MachineFunctionAnalysisManager *,
-                                 const std::string &Banner,
+void llvm::verifyMachineFunction(const std::string &Banner,
                                  const MachineFunction &MF) {
   // TODO: Use MFAM after porting below analyses.
   // LiveVariables *LiveVars;

diff --git a/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp b/llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp
@@ -334,16 +334,11 @@ namespace {
     }
 
     bool SimplifyDemandedBits(SDValue Op, const APInt &DemandedBits) {
-      TargetLowering::TargetLoweringOpt TLO(DAG, LegalTypes, LegalOperations);
-      KnownBits Known;
-      if (!TLI.SimplifyDemandedBits(Op, DemandedBits, Known, TLO, 0, false))
-        return false;
-
-      // Revisit the node.
-      AddToWorklist(Op.getNode());
-
-      CommitTargetLoweringOpt(TLO);
-      return true;
+      EVT VT = Op.getValueType();
+      APInt DemandedElts = VT.isFixedLengthVector()
+                               ? APInt::getAllOnes(VT.getVectorNumElements())
+                               : APInt(1, 1);
+      return SimplifyDemandedBits(Op, DemandedBits, DemandedElts, false);
     }
 
     /// Check the specified vector node value to see if it can be simplified or
@@ -12744,12 +12739,12 @@ static SDValue tryToFoldExtendSelectLoad(SDNode *N, const TargetLowering &TLI,
 /// dag nodes (see for example method DAGCombiner::visitSIGN_EXTEND).
 /// Vector extends are not folded if operations are legal; this is to
 /// avoid introducing illegal build_vector dag nodes.
-static SDValue tryToFoldExtendOfConstant(SDNode *N, const TargetLowering &TLI,
+static SDValue tryToFoldExtendOfConstant(SDNode *N, const SDLoc &DL,
+                                         const TargetLowering &TLI,
                                          SelectionDAG &DAG, bool LegalTypes) {
   unsigned Opcode = N->getOpcode();
   SDValue N0 = N->getOperand(0);
   EVT VT = N->getValueType(0);
-  SDLoc DL(N);
 
   assert((ISD::isExtOpcode(Opcode) || ISD::isExtVecInRegOpcode(Opcode)) &&
          "Expected EXTEND dag node in input!");
@@ -13405,7 +13400,7 @@ SDValue DAGCombiner::visitSIGN_EXTEND(SDNode *N) {
   if (N0.isUndef())
     return DAG.getConstant(0, DL, VT);
 
-  if (SDValue Res = tryToFoldExtendOfConstant(N, TLI, DAG, LegalTypes))
+  if (SDValue Res = tryToFoldExtendOfConstant(N, DL, TLI, DAG, LegalTypes))
     return Res;
 
   // fold (sext (sext x)) -> (sext x)
@@ -13674,7 +13669,7 @@ SDValue DAGCombiner::visitZERO_EXTEND(SDNode *N) {
   if (N0.isUndef())
     return DAG.getConstant(0, DL, VT);
 
-  if (SDValue Res = tryToFoldExtendOfConstant(N, TLI, DAG, LegalTypes))
+  if (SDValue Res = tryToFoldExtendOfConstant(N, DL, TLI, DAG, LegalTypes))
     return Res;
 
   // fold (zext (zext x)) -> (zext x)
@@ -13942,12 +13937,13 @@ SDValue DAGCombiner::visitZERO_EXTEND(SDNode *N) {
 SDValue DAGCombiner::visitANY_EXTEND(SDNode *N) {
   SDValue N0 = N->getOperand(0);
   EVT VT = N->getValueType(0);
+  SDLoc DL(N);
 
   // aext(undef) = undef
   if (N0.isUndef())
     return DAG.getUNDEF(VT);
 
-  if (SDValue Res = tryToFoldExtendOfConstant(N, TLI, DAG, LegalTypes))
+  if (SDValue Res = tryToFoldExtendOfConstant(N, DL, TLI, DAG, LegalTypes))
     return Res;
 
   // fold (aext (aext x)) -> (aext x)
@@ -13956,15 +13952,15 @@ SDValue DAGCombiner::visitANY_EXTEND(SDNode *N) {
   if (N0.getOpcode() == ISD::ANY_EXTEND  ||
       N0.getOpcode() == ISD::ZERO_EXTEND ||
       N0.getOpcode() == ISD::SIGN_EXTEND)
-    return DAG.getNode(N0.getOpcode(), SDLoc(N), VT, N0.getOperand(0));
+    return DAG.getNode(N0.getOpcode(), DL, VT, N0.getOperand(0));
 
   // fold (aext (aext_extend_vector_inreg x)) -> (aext_extend_vector_inreg x)
   // fold (aext (zext_extend_vector_inreg x)) -> (zext_extend_vector_inreg x)
   // fold (aext (sext_extend_vector_inreg x)) -> (sext_extend_vector_inreg x)
   if (N0.getOpcode() == ISD::ANY_EXTEND_VECTOR_INREG ||
       N0.getOpcode() == ISD::ZERO_EXTEND_VECTOR_INREG ||
       N0.getOpcode() == ISD::SIGN_EXTEND_VECTOR_INREG)
-    return DAG.getNode(N0.getOpcode(), SDLoc(N), VT, N0.getOperand(0));
+    return DAG.getNode(N0.getOpcode(), DL, VT, N0.getOperand(0));
 
   // fold (aext (truncate (load x))) -> (aext (smaller load x))
   // fold (aext (truncate (srl (load x), c))) -> (aext (small load (x+c/n)))
@@ -13982,15 +13978,14 @@ SDValue DAGCombiner::visitANY_EXTEND(SDNode *N) {
 
   // fold (aext (truncate x))
   if (N0.getOpcode() == ISD::TRUNCATE)
-    return DAG.getAnyExtOrTrunc(N0.getOperand(0), SDLoc(N), VT);
+    return DAG.getAnyExtOrTrunc(N0.getOperand(0), DL, VT);
 
   // Fold (aext (and (trunc x), cst)) -> (and x, cst)
   // if the trunc is not free.
   if (N0.getOpcode() == ISD::AND &&
       N0.getOperand(0).getOpcode() == ISD::TRUNCATE &&
       N0.getOperand(1).getOpcode() == ISD::Constant &&
       !TLI.isTruncateFree(N0.getOperand(0).getOperand(0), N0.getValueType())) {
-    SDLoc DL(N);
     SDValue X = DAG.getAnyExtOrTrunc(N0.getOperand(0).getOperand(0), DL, VT);
     SDValue Y = DAG.getNode(ISD::ANY_EXTEND, DL, VT, N0.getOperand(1));
     assert(isa<ConstantSDNode>(Y) && "Expected constant to be folded!");
@@ -14016,9 +14011,9 @@ SDValue DAGCombiner::visitANY_EXTEND(SDNode *N) {
           ExtendUsesToFormExtLoad(VT, N, N0, ISD::ANY_EXTEND, SetCCs, TLI);
     if (DoXform) {
       LoadSDNode *LN0 = cast<LoadSDNode>(N0);
-      SDValue ExtLoad = DAG.getExtLoad(ISD::EXTLOAD, SDLoc(N), VT,
-                                       LN0->getChain(), LN0->getBasePtr(),
-                                       N0.getValueType(), LN0->getMemOperand());
+      SDValue ExtLoad = DAG.getExtLoad(ISD::EXTLOAD, DL, VT, LN0->getChain(),
+                                       LN0->getBasePtr(), N0.getValueType(),
+                                       LN0->getMemOperand());
       ExtendSetCCUses(SetCCs, N0, ExtLoad, ISD::ANY_EXTEND);
       // If the load value is used only by N, replace it via CombineTo N.
       bool NoReplaceTrunc = N0.hasOneUse();
@@ -14044,9 +14039,9 @@ SDValue DAGCombiner::visitANY_EXTEND(SDNode *N) {
     ISD::LoadExtType ExtType = LN0->getExtensionType();
     EVT MemVT = LN0->getMemoryVT();
     if (!LegalOperations || TLI.isLoadExtLegal(ExtType, VT, MemVT)) {
-      SDValue ExtLoad = DAG.getExtLoad(ExtType, SDLoc(N),
-                                       VT, LN0->getChain(), LN0->getBasePtr(),
-                                       MemVT, LN0->getMemOperand());
+      SDValue ExtLoad =
+          DAG.getExtLoad(ExtType, DL, VT, LN0->getChain(), LN0->getBasePtr(),
+                         MemVT, LN0->getMemOperand());
       CombineTo(N, ExtLoad);
       DAG.ReplaceAllUsesOfValueWith(SDValue(LN0, 1), ExtLoad.getValue(1));
       recursivelyDeleteUnusedNodes(LN0);
@@ -14074,23 +14069,20 @@ SDValue DAGCombiner::visitANY_EXTEND(SDNode *N) {
       // we know that the element size of the sext'd result matches the
       // element size of the compare operands.
       if (VT.getSizeInBits() == N00VT.getSizeInBits())
-        return DAG.getSetCC(SDLoc(N), VT, N0.getOperand(0),
-                             N0.getOperand(1),
-                             cast<CondCodeSDNode>(N0.getOperand(2))->get());
+        return DAG.getSetCC(DL, VT, N0.getOperand(0), N0.getOperand(1),
+                            cast<CondCodeSDNode>(N0.getOperand(2))->get());
 
       // If the desired elements are smaller or larger than the source
       // elements we can use a matching integer vector type and then
       // truncate/any extend
       EVT MatchingVectorType = N00VT.changeVectorElementTypeToInteger();
-      SDValue VsetCC =
-        DAG.getSetCC(SDLoc(N), MatchingVectorType, N0.getOperand(0),
-                      N0.getOperand(1),
-                      cast<CondCodeSDNode>(N0.getOperand(2))->get());
-      return DAG.getAnyExtOrTrunc(VsetCC, SDLoc(N), VT);
+      SDValue VsetCC = DAG.getSetCC(
+          DL, MatchingVectorType, N0.getOperand(0), N0.getOperand(1),
+          cast<CondCodeSDNode>(N0.getOperand(2))->get());
+      return DAG.getAnyExtOrTrunc(VsetCC, DL, VT);
     }
 
     // aext(setcc x,y,cc) -> select_cc x, y, 1, 0, cc
-    SDLoc DL(N);
     if (SDValue SCC = SimplifySelectCC(
             DL, N0.getOperand(0), N0.getOperand(1), DAG.getConstant(1, DL, VT),
             DAG.getConstant(0, DL, VT),
@@ -14642,10 +14634,9 @@ SDValue DAGCombiner::visitSIGN_EXTEND_INREG(SDNode *N) {
   return SDValue();
 }
 
-static SDValue
-foldExtendVectorInregToExtendOfSubvector(SDNode *N, const TargetLowering &TLI,
-                                         SelectionDAG &DAG,
-                                         bool LegalOperations) {
+static SDValue foldExtendVectorInregToExtendOfSubvector(
+    SDNode *N, const SDLoc &DL, const TargetLowering &TLI, SelectionDAG &DAG,
+    bool LegalOperations) {
   unsigned InregOpcode = N->getOpcode();
   unsigned Opcode = DAG.getOpcode_EXTEND(InregOpcode);
 
@@ -14672,28 +14663,29 @@ foldExtendVectorInregToExtendOfSubvector(SDNode *N, const TargetLowering &TLI,
   if (LegalOperations && !TLI.isOperationLegal(Opcode, VT))
     return SDValue();
 
-  return DAG.getNode(Opcode, SDLoc(N), VT, Src);
+  return DAG.getNode(Opcode, DL, VT, Src);
 }
 
 SDValue DAGCombiner::visitEXTEND_VECTOR_INREG(SDNode *N) {
   SDValue N0 = N->getOperand(0);
   EVT VT = N->getValueType(0);
+  SDLoc DL(N);
 
   if (N0.isUndef()) {
     // aext_vector_inreg(undef) = undef because the top bits are undefined.
     // {s/z}ext_vector_inreg(undef) = 0 because the top bits must be the same.
     return N->getOpcode() == ISD::ANY_EXTEND_VECTOR_INREG
                ? DAG.getUNDEF(VT)
-               : DAG.getConstant(0, SDLoc(N), VT);
+               : DAG.getConstant(0, DL, VT);
   }
 
-  if (SDValue Res = tryToFoldExtendOfConstant(N, TLI, DAG, LegalTypes))
+  if (SDValue Res = tryToFoldExtendOfConstant(N, DL, TLI, DAG, LegalTypes))
     return Res;
 
   if (SimplifyDemandedVectorElts(SDValue(N, 0)))
     return SDValue(N, 0);
 
-  if (SDValue R = foldExtendVectorInregToExtendOfSubvector(N, TLI, DAG,
+  if (SDValue R = foldExtendVectorInregToExtendOfSubvector(N, DL, TLI, DAG,
                                                            LegalOperations))
     return R;
 

diff --git a/llvm/lib/CodeGen/SelectionDAG/FastISel.cpp b/llvm/lib/CodeGen/SelectionDAG/FastISel.cpp
@@ -1197,7 +1197,8 @@ void FastISel::handleDbgInfo(const Instruction *II) {
       V = DPV.getVariableLocationOp(0);
 
     bool Res = false;
-    if (DPV.getType() == DPValue::LocationType::Value) {
+    if (DPV.getType() == DPValue::LocationType::Value ||
+        DPV.getType() == DPValue::LocationType::Assign) {
       Res = lowerDbgValue(V, DPV.getExpression(), DPV.getVariable(),
                           DPV.getDebugLoc());
     } else {
@@ -1393,6 +1394,13 @@ bool FastISel::selectIntrinsicCall(const IntrinsicInst *II) {
 
     return true;
   }
+  case Intrinsic::dbg_assign:
+    // A dbg.assign is a dbg.value with more information, typically produced
+    // during optimisation. If one reaches fastisel then something odd has
+    // happened (such as an optimised function being always-inlined into an
+    // optnone function). We will not be using the extra information in the
+    // dbg.assign in that case, just use its dbg.value fields.
+    LLVM_FALLTHROUGH;
   case Intrinsic::dbg_value: {
     // This form of DBG_VALUE is target-independent.
     const DbgValueInst *DI = cast<DbgValueInst>(II);

diff --git a/llvm/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp b/llvm/lib/CodeGen/SelectionDAG/LegalizeIntegerTypes.cpp
@@ -2897,6 +2897,8 @@ void DAGTypeLegalizer::ExpandShiftByConstant(SDNode *N, const APInt &Amt,
 /// shift amount.
 bool DAGTypeLegalizer::
 ExpandShiftWithKnownAmountBit(SDNode *N, SDValue &Lo, SDValue &Hi) {
+  unsigned Opc = N->getOpcode();
+  SDValue In = N->getOperand(0);
   SDValue Amt = N->getOperand(1);
   EVT NVT = TLI.getTypeToTransformTo(*DAG.getContext(), N->getValueType(0));
   EVT ShTy = Amt.getValueType();
@@ -2907,15 +2909,15 @@ ExpandShiftWithKnownAmountBit(SDNode *N, SDValue &Lo, SDValue &Hi) {
   SDLoc dl(N);
 
   APInt HighBitMask = APInt::getHighBitsSet(ShBits, ShBits - Log2_32(NVTBits));
-  KnownBits Known = DAG.computeKnownBits(N->getOperand(1));
+  KnownBits Known = DAG.computeKnownBits(Amt);
 
   // If we don't know anything about the high bits, exit.
-  if (((Known.Zero|Known.One) & HighBitMask) == 0)
+  if (((Known.Zero | Known.One) & HighBitMask) == 0)
     return false;
 
   // Get the incoming operand to be shifted.
   SDValue InL, InH;
-  GetExpandedInteger(N->getOperand(0), InL, InH);
+  GetExpandedInteger(In, InL, InH);
 
   // If we know that any of the high bits of the shift amount are one, then we
   // can do this as a couple of simple shifts.
@@ -2924,7 +2926,7 @@ ExpandShiftWithKnownAmountBit(SDNode *N, SDValue &Lo, SDValue &Hi) {
     Amt = DAG.getNode(ISD::AND, dl, ShTy, Amt,
                       DAG.getConstant(~HighBitMask, dl, ShTy));
 
-    switch (N->getOpcode()) {
+    switch (Opc) {
     default: llvm_unreachable("Unknown shift");
     case ISD::SHL:
       Lo = DAG.getConstant(0, dl, NVT);              // Low part is zero.
@@ -2952,15 +2954,15 @@ ExpandShiftWithKnownAmountBit(SDNode *N, SDValue &Lo, SDValue &Hi) {
                                DAG.getConstant(NVTBits - 1, dl, ShTy));
 
     unsigned Op1, Op2;
-    switch (N->getOpcode()) {
+    switch (Opc) {
     default: llvm_unreachable("Unknown shift");
     case ISD::SHL:  Op1 = ISD::SHL; Op2 = ISD::SRL; break;
     case ISD::SRL:
     case ISD::SRA:  Op1 = ISD::SRL; Op2 = ISD::SHL; break;
     }
 
     // When shifting right the arithmetic for Lo and Hi is swapped.
-    if (N->getOpcode() != ISD::SHL)
+    if (Opc != ISD::SHL)
       std::swap(InL, InH);
 
     // Use a little trick to get the bits that move from Lo to Hi. First
@@ -2969,10 +2971,10 @@ ExpandShiftWithKnownAmountBit(SDNode *N, SDValue &Lo, SDValue &Hi) {
     // Then compute the remaining shift with amount-1.
     SDValue Sh2 = DAG.getNode(Op2, dl, NVT, Sh1, Amt2);
 
-    Lo = DAG.getNode(N->getOpcode(), dl, NVT, InL, Amt);
+    Lo = DAG.getNode(Opc, dl, NVT, InL, Amt);
     Hi = DAG.getNode(ISD::OR, dl, NVT, DAG.getNode(Op1, dl, NVT, InH, Amt),Sh2);
 
-    if (N->getOpcode() != ISD::SHL)
+    if (Opc != ISD::SHL)
       std::swap(Hi, Lo);
     return true;
   }