Optimize instruction prefix extraction loops#88
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r0ny123 wants to merge 5 commits intodanielplohmann:masterfrom
Open
Optimize instruction prefix extraction loops#88r0ny123 wants to merge 5 commits intodanielplohmann:masterfrom
r0ny123 wants to merge 5 commits intodanielplohmann:masterfrom
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Replaced inefficient list comprehensions with inline generator-like behavior in `getByteWithoutPrefixes` and `escapeToOpcodeOnly`. By using a static, class-level set `_PREFIXES` and doing straight array slicing, we avoid intermediate memory allocations and improve iteration performance by roughly 2x. Co-authored-by: google-labs-jules[bot] <161369871+google-labs-jules[bot]@users.noreply.github.com>
Replace the for/else loop in escapeToOpcodeOnly with a more idiomatic next() expression as suggested in code review, and apply the same pattern to getByteWithoutPrefixes for consistency. Also bind the class-level _PREFIXES set to a local name to avoid repeated attribute lookups inside the generator.
Move _PREFIXES up next to the other class-level constants for consistency with the existing structure, and factor the duplicated prefix-length scan out of escapeToOpcodeOnly and getByteWithoutPrefixes into a shared _getPrefixLen helper.
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💡 What:
_PREFIXESset to cache prefix lookups insmda/intel/IntelInstructionEscaper.py.[ins_bytes[i: i+2] ...]ingetByteWithoutPrefixesandescapeToOpcodeOnlywith sequential string slicing directly.🎯 Why:
📊 Measured Improvement:
getByteWithoutPrefixesandescapeToOpcodeOnlyover 100k instructions showed approx a 2x overall runtime improvement:getByteWithoutPrefixes: 0.99s -> 0.41sescapeToOpcodeOnly: 1.38s -> 0.74s