⚡ Bolt: Hoist static lookup tables and rely on LLVM branchless optimization#11
⚡ Bolt: Hoist static lookup tables and rely on LLVM branchless optimization#11shuwang1 wants to merge 1 commit into
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…zation * Extract `octList` and `hexList` in `GNSSCodes.swift` to `private static let` properties to eliminate repeated heap allocations. * Revert manual branchless bitwise logic in `GPS.swift` to standard conditional ternaries, allowing LLVM CMOV/CSEL compiler optimizations to handle branching performantly without sacrificing code readability. * Document learnings in `.jules/bolt.md`. Co-authored-by: shuwang1 <12467002+shuwang1@users.noreply.github.com>
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💡 What: Extracted
octListandhexListlocally instantiated array variables insideoct2bin/hex2binhelper functions intoprivate static letclass properties. Additionally, reverted an unreadable manual branchless bitwise math hack ingenerateL2Cback to standard conditional ternaries.🎯 Why: Instantiating multidimensional arrays inside frequently called generator loops causes massive, repeated heap allocations and garbage collection thrashing in Swift. Furthermore, manual bitwise hacks for branch prediction are unnecessary since modern Swift compilers (LLVM) natively compile simple ternary operators into branchless
CMOV/CSELCPU instructions, delivering the same performance with vastly better readability.📊 Impact: Reduces memory allocation overhead (heap pressure) to almost zero in the
oct2bin/hex2binpaths. Improves code maintainability without performance loss in PRN sequence generation loops.🔬 Measurement: Verify via memory profiling during GNSS code generation (heap allocations will be noticeably reduced for L1CO initialization). Verify LFSR output correctness through CI test suite runs.
PR created automatically by Jules for task 15435339998479644984 started by @shuwang1