[clang-tools-extra] [clang-tidy] Add check performance-lost-std-move (PR #139525)

[Vasiliy Kulikov via cfe-commits]

================
@@ -0,0 +1,32 @@
+.. title:: clang-tidy - performance-lost-std-move
+
+performance-lost-std-move
+=========================
+
+Warns if copy constructor is used instead of std::move() and suggests a fix.
+It honours cycles, lambdas, and unspecified call order in compound expressions.
+
+.. code-block:: c++
+
+   void f(X);
+
+   void g(X x) {
+     f(x);  // warning: Could be std::move() [performance-lost-std-move]
+   }
+
+It finds the last local variable usage, and if it is a copy, emits a warning.
+The check is based on pure AST matching and doesn't take into account any data flow information.
+Thus, it doesn't catch assign-after-copy cases.
+Also it doesn't notice variable references "behind the scenes":
+
+.. code-block:: c++
+
+   void f(X);
+
+   void g(X x) {
+     auto &y = x;
+     f(x);  // emits a warning...
+     y.f();  // ...but it is still used
+   }
----------------
segoon wrote:

The problem is that any binding to a reference should skip the check. E.g.
```
void f(X);
void g(X&);

void func(X x) {
  g(x); // reference is created, we may not move from x anymore
  f(x); // no fix
}
```
I'm afraid too many cases are skipped due to this problem.

https://github.com/llvm/llvm-project/pull/139525