[llvm] [ADT] Add SmallVectorImpl::append_range (PR #93384)

[Jakub Kuderski via llvm-commits]

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@@ -701,6 +701,10 @@ class SmallVectorImpl : public SmallVectorTemplateBase<T> {
     this->set_size(this->size() + NumInputs);
   }
 
+  template <typename RangeTy> void append_range(RangeTy &&R) {
+    this->append(R.begin(), R.end());
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kuhar wrote:

We can't reuse the storage but we should be able to move the elements, no? E.g., skip allocations when appending a temporary range of `std::string`s. Maybe something based on `make_move_iterator` could work?

BTW, I think this should also use `adl_being`/`end`.

https://github.com/llvm/llvm-project/pull/93384