T.shfl_sync, T.shfl_xor, T.shfl_down, and T.shfl_up lower to CUDA's raw
__shfl_*_sync builtins. CUDA has no exact overloads for the narrow
floating-point wrappers TileLang emits, so calls either resolved to the
float overload and returned a float that could not copy-initialize the
wrapper, or were ambiguous. Either way the shuffle failed to compile.
Add exact non-template overloads for half_t, bfloat16_t, float_e4m3_t, and
float_e5m2_t. The overloads carry the raw bits through CUDA's uint32_t
shuffle and preserve mask, lane, delta, and width semantics. A local macro
generates the four builtin overloads per type and is undefined immediately
after use, leaving codegen and native CUDA overload resolution unchanged.
Add exact lane-permutation coverage for all four shuffle operations and all
four wrapper types in both materialized-temporary and inline forms.
Fixes#2569
Chennes
e54cbabb12