snapshot: non-temporal memcpy #4869
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asiegel-jt
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Apr 25, 2025
| /* NT copy */ | ||
| while( sz>=512 ) { | ||
| # if FD_HAS_AVX512 | ||
| _mm512_stream_si512( (void *)( dst+ 0UL ), _mm512_loadu_si512( (void const *)( src+ 0UL ) ) ); |
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It's a bit faster to do the stores a few instructions after the loads. The secret is interleaving. This keeps the memory pipeline full.
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Doesn't the CPU's op reorder buffer already do this optimization for us? I'm almost certain the CPU should be able to schedule additional loads whenever it's waiting for a load to complete.
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How deep is the speculative execution buffer?
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Closes #4815