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Native 128-bit VSX implementations of the wavelet, colour, and codestream kernels and the HTJ2K block decoder, with runtime dispatch via hwcap. Supported targets are POWER9 (ISA 3.0) and newer, little-endian only; other PPC targets use the generic code paths. Beyond a straight port, the kernels use POWER-specific forms where measurement showed a win: xvrspi for round-to-nearest-away in the float-to-int conversions, vec_sel for masked selects, and a block decoder that destuffs the MagSgn bitstream upfront so per-quad bit consumption is a GPR add instead of a vector-window shift. The SIMD block decoder is dispatched everywhere on POWER10, and for irreversible tile components on POWER9, where it beats the scalar decoder; reversible content on POWER9 stays scalar, which is slightly faster there. Assisted-by: Lance Albertson <lance@osuosl.org> Assisted-by: Thushan Fernando <thushan@thushanfernando.com> Co-authored-by: Claude Fable 5 <noreply@anthropic.com>
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@runlevel5. Kind regards, |
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Adds support for powerpc64le.
The original contributor is @runlevel5 in #282.