What Is Peephole Optimization?
Peephole optimization is a local transformation that looks at a short sequence of adjacent instructions and rewrites recognizable inefficient patterns into faster ones. Typical examples include removing redundant loads, collapsing jumps to jumps, and replacing a multiply by a power of two with a shift. It works on the small window rather than the whole program.
Why it matters
Many small inefficiencies survive earlier passes and are easiest to catch by pattern-matching a few instructions at a time. Peephole passes clean these up cheaply right before final code emission.
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