Optimization: Introduction
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Gist: Optimizer makes a more efficient version of the intermediate or target code
1) Local optimization ´ Global optimization
• Local optimization – within a basic block
• Global optimization – span several basic blocks
Variants of optimizations:
2) Optimization for speed ´ Optimization for size
1) Constant folding
2) Constant propagation
3) Copy propagation
Optimization methods:
4) Loop invariant expressions
5) Loop unrolling
6) Dead code elimination