mirror of https://github.com/YosysHQ/yosys.git
643427d9c9
This commit introduces the negopt pass with pre/post optimization modes for handling negation patterns in arithmetic circuits. Pre-optimization patterns (expose for tree balancing): - manual2sub: (a + ~b) + 1 → a - b - sub2neg: a - b → a + (-b) - negexpand: -(a + b) → (-a) + (-b) [with output width fix] - negneg: -(-a) → a - negmux: -(s ? a : b) → s ? (-a) : (-b) Post-optimization patterns (cleanup/rebuild): - negrebuild: (-a) + (-b) → -(a + b) - muxneg: s ? (-a) : (-b) → -(s ? a : b) - neg2sub: a + (-b) → a - b All patterns use nusers() for fanout checking (standard Yosys style). Comprehensive test coverage with positive/negative cases and formal verification via equiv_opt. |
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| .. | ||
| cmds | ||
| equiv | ||
| fsm | ||
| hierarchy | ||
| memory | ||
| opt | ||
| pmgen | ||
| proc | ||
| sat | ||
| silimate | ||
| techmap | ||
| tests | ||