⚡ Bolt: Optimize generateL5 with branchless arithmetic#5
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- Replaced conditional ternary with branchless math in L5 PRN generation loop. - Avoids pipeline flushes from branch mispredictions. Co-authored-by: shuwang1 <12467002+shuwang1@users.noreply.github.com>
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💡 What: Replaced the conditional ternary operator (
!= 0 ? 1 : -1) inside thegenerateL5inner loop with branchless bitwise arithmetic(output << 1) - 1.🎯 Why: The loop runs 10,230 times per L5 code generation. Conditional logic inside such hot loops can lead to CPU branch mispredictions and costly pipeline flushes, acting as a performance bottleneck as documented in
.jules/bolt.md.📊 Impact: Reduces cycle time by preventing pipeline flushes in LFSR loops, resulting in faster and more consistent execution time for GPS L5 code generation.
🔬 Measurement: Profile the execution time of
GNSSCodes.generateL5IandGNSSCodes.generateL5Qfor large batches of codes before and after this optimization. Verify that generatedGNSSCodesare identical.PR created automatically by Jules for task 8127367969914533086 started by @shuwang1