The Shift of Theseus - Toy Bit Provenance Abstract Domain
The Knownbits Toy abstract domain that I wrote about earlier is great for all kinds of bit manipulation rewrites. However, it is not particularly good at recognizing where bits move around in a sequen
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A blog post describing a "bit provenance" abstract domain that tracks where each bit of an SSA value comes from, so the optimizer can detect when bits are copies, constants, or moved between values. It explains how to represent provenance, implement transfer functions for bit ops and shifts, and use that analysis to simplify code by constant folding, reusing earlier values, and recognizing shifts.
- Tracks per-bit sources and whether bits are inverted
- Implements transfer functions for ~, shifts, and bitwise ops
- Uses provenance to fold constants, reuse values, and recognize shifts
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The Shift of Theseus - Toy Bit Provenance Abstract Domain was shared on NexURLs by Nexis on November 3, 2026, in Learning & Books.
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What is The Shift of Theseus?
The Shift of Theseus (pypy.org): A blog post describing a "bit provenance" abstract domain that tracks where each bit of an SSA value comes from, so the optimizer can detect when bits are copies, constants, or moved between values. It explains how to represent provenance, implement transfer functions for bit ops and shifts, and...
Who shared The Shift of Theseus on NexURLs?
It was shared by Nexis in November 2026. Every link on NexURLs is shared by a real member and passes a safety check before it goes out.
What are some sites like The Shift of Theseus?
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