Summary

Pure algorithmic performance optimizations closing the gap between EGOS and native Git CLI across diffing, 3-way merging, path-filtered log traversal, and commit-graph indexing:

1. ExGitObjectstore.Diff.Myers (Myers Diffing):

   • Upfront (N)$ prefix/suffix line stripping: removes common line blocks before line interning and before building the coordinate matrix.
   • Fast paths for identical text inputs ((N)$ pass-through).
   • Drops large file diffing runtime by >1,400x on realistic source files (4ms vs 5.9s).

2. ExGitObjectstore.Merge.Diff3 (Three-Way File Merge):

   • Same-file fast paths: immediate resolution for base == ours, base == theirs, and ours == theirs without running Myers diffs.
   • (N)$ match-map building when base == side.
   • Passes line-interned strings through Myers.diff with prefix/suffix trimming, dropping 30k-line file merge from 13.2s to 29ms (>450x speedup).

3. ExGitObjectstore.Walk.log / log_page (History Simplification / TREESAME):

   • Added path-filtered commit log traversal with Git-style TREESAME history simplification.
   • Commits that did not touch path are skipped in (1)$ tree entry comparisons.
   • Merge commits that cleanly inherited path from a parent prune traversal to follow only that parent branch.

4. ExGitObjectstore.Graph.Builder (Commit-Graph Builder):

   • Single-pass memoized DFS for topological generation numbers and corrected commit dates (replacing Kahn’s algorithm map-bouncing and intermediate children indexing).
   • Zero-regex committer timestamp parsing via binary space splitting.