c2pkg — C2SIMD Sovereign Transpiled Packages (Pure Go / CGO=0)

c2pkg provides high-performance, pure-Go algorithmic packages mechanically transpiled from C99/C23 reference implementations by the sgoiter compiler (Go 1.27+ with GOEXPERIMENT=simd).

All packages provide strict invariants:

• Zero CGO / 100% Pure Go: No dynamic C runtime dependencies.
• Bit-Exact Parity: Verified against C99 oracles compiled with gcc -O2 under ASan/UBSan.
• Zero Heap Allocations: On hot compute paths.
• Hardware Acceleration: Native SIMD intrinsics (AVX2, AVX-512, ARM NEON).

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Package Catalog

Package	Upstream C Source	Description & Invariants
c2archtsim	c2archsimd.c	ARCHTIME .rodata tables, LUT16/LUT256 shuffles, vectorized hex codec.
c2chacha1-8	monocypher.c / RFC 8439	Constant-time ChaCha stream ciphers (1, 2, 4, 8 rounds) with 0-alloc state.
c2poly1305	poly1305.c	RFC 8439 Poly1305 authenticator with 128-bit fused carry arithmetic.
c2poly1305x8	poly1305.c	8-way parallel Poly1305 pipelined vector implementation.
c2blake2b	blake2b.c	High-throughput BLAKE2b cryptographic hashing with SIMD round unrolling.
blake3archtsim	blake3.c	Parallel tree-hashing BLAKE3 implementation with AVX2 backend.
c2lz4	lz4.c	High-speed compression / decompression with zero heap churn.
c2ryu	ryu.c	Ultra-fast float-to-string conversion with constant-table lookup.
c2json	simdjson.c	Vectorized structural JSON parser with stage 1/stage 2 bitmask sweeps.
c2pcre	pcre.c	Regular expression matching engine with DFA fast-path.
c2ordered_swiss	abseil/swiss_table	Cache-friendly ordered hash map with SIMD metadata group probing.
c2uuidv7	uuidv7.c	Monotonic UUIDv7 timestamp generator (0 allocs).
c2vtparser	vtparser.c	State-machine ANSI/VT500 escape sequence parser (Paul Flo Williams tables).
c2myers	myers.c	Vectorized Myers O(ND) diffing algorithm for text buffers.
c2swizzle	swizzle.c	RGBA <-> BGRA pixel transposition via vpshufb (>= 36 GB/s).
c2ssim	ssim.c	Separable 11x11 Gaussian blur and structural similarity index calculation.

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Probes & Research

• probes/abi_sroa_bench: Isolated micro-benchmarks comparing parameter passing overhead ([2]uint64 array stack spill vs struct{Lo, Hi uint64} register ABI in Go 1.27).

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Validation & Verification

All packages are validated under race detection:

GOEXPERIMENT=simd go test -v -race ./...

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License

Apache-2.0 OR MIT (with respective upstream attribution in COPYRIGHT.md).