[CK] Replace tuple value construction with tuple_element_t
type extraction [1A] (#5030)
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## Summary
### Rationale
CK's device operation instance registration uses
`add_device_operation_instances` at ~1,850
call sites to register GPU kernel configurations. The existing
implementation constructs
`std::tuple` values just to extract their types via `decltype`, then
copy-constructs each
instance into `make_unique`. This is wasteful — only the types matter,
not the values — and
forces the compiler to instantiate the full `std::tuple` constructor and
`std::get` machinery
at every call site.
### What changed
- Replace `remove_cvref_t<decltype(std::get<i>(tuple_obj))>` with
`std::tuple_element_t<i.value, TupleType>`, which extracts the type
directly without constructing any values
- Replace copy-from-default `make_unique<T>(value)` with direct default
construction `make_unique<T>()` — all CK device operation instances are
stateless structs with configuration encoded in template parameters
- Add `static_assert(std::is_default_constructible_v<NewOpInstance>)` to
enforce this contract at compile time with a clear error message
- Add Doxygen documentation for this high-traffic public API
### Value
- Eliminates unnecessary template instantiation of `std::tuple`
constructors and `std::get` across ~1,850 call sites
- Establishes a cleaner, more intention-revealing pattern for type-only
tuple usage
- The `static_assert` prevents silent breakage if a
non-default-constructible type is ever added
- No runtime behavior change — zero risk
### Files changed (9)
- `add_device_operation_instance.hpp`: Core pattern change
- 3 example files, 3 reduce instance headers, 1 convolution header, 1
profiler header
## Test plan
- [ ] Existing CI tests cover all ~1,850 call sites (GEMM, reduce,
softmax, convolution)
- [ ] `static_assert` provides compile-time validation stronger than
runtime tests
- [ ] No runtime behavior change — stateless struct default construction
is identical to copy-from-default
- [ ] Compatible with both `std::tuple` and `ck::type_list` containers
🤖 Generated with [Claude Code](https://claude.com/claude-code)
## Submission Checklist
- [ ] Look over the contributing guidelines at
https://github.com/ROCm/ROCm/blob/develop/CONTRIBUTING.md#pull-requests.
* Simplify the macros for declaring and defining the add_device_reduce_instance_xxxx() instances
* Change the types of lengths and strides from std::vector to std::array for the reduction device interfaces
* Remove DeviceSoftmaxImpl's depending on DeviceReduceMultiblock
* Split the cpp and hpp files for reduction instances to enable more parallel compiling
* Remove the using of macros for declaring reduction instances and instance references
* Update to add_device_reduce_instance_xxxx templated functions
* Use ReduceOperation+InElementwiseOp+AccElementwiseOp to repace the ReduceOpId in defining add_reduce_instance_xxxx() templates
* Change return format
* Update the reduce_blockwise example to support user specified data type and input+reducing dimensions
* Add examples for using reduce_multiblock_atomic_add
* Add more running examples to the default command-line
* Remove un-necessary header including
* Update to the example README.md
