POET

POET is a header-only C++ library for compile-time unrolling and runtime-to-compile-time specialization.

Core primitives

  • static_for: compile-time unrolled loops over integer ranges

  • dynamic_for: runtime loops emitted as compile-time unrolled blocks

  • dispatch / dispatch_set: runtime choice mapped to compile-time specializations

  • CPU detection: ISA, vector-width, and cache-line helpers (poet::available_registers(), poet::cache_line())

Quick start

Note

Try it online. Each example has a one-click Compiler Explorer link that pulls the single-header build from GitHub at compile time via Compiler Explorer’s URL-include feature.

Source for each example lives in examples/; regenerate the links with tools/make_godbolt_links.py.

Include the umbrella header:

#include <poet/poet.hpp>

Minimal examples:

poet::static_for<0, 4>([](auto I) {
    use_index(I);
});

poet::dynamic_for<4>(0u, n, [](std::size_t i) {
    out[i] = f(i);
});

auto y = poet::dispatch(
    Kernel{},
    poet::dispatch_param<poet::inclusive_range<0, 4>>{choice},
    x);

Notes

  • poet::inclusive_range<Start, End> is inclusive on both ends.

  • dynamic_for is most useful with the lane-aware callback form for multi-accumulator work.

  • The C++20 make_dynamic_for adaptor is eager.

Next reads

Getting Started

Guides

API Reference