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Diffstat (limited to 'docs/coding.md')
| -rw-r--r-- | docs/coding.md | 2 |
1 files changed, 1 insertions, 1 deletions
diff --git a/docs/coding.md b/docs/coding.md index 355fe457..dc09bb3f 100644 --- a/docs/coding.md +++ b/docs/coding.md @@ -75,7 +75,7 @@ The job of the placer in nextpnr is to find a suitable bel for each cell in the Placers might want to create their own indices of bels (for example, bels by type and location) to speed up the search. -As nextpnr allows arbitrary constraints on bels for more advanced packer-free flows and complex real-world architectures; placements must be checked for legality using `isValidBelForCell` (before placement) or `isBelLocationValid` (after placement) and the placement rejected if invalid. For analytical placement algorithms; after creating a spread-out AP solution the legality of placing each cell needs to be checked. In practice, the cost of this is fairly low as the architecture should ensure these functions are as fast as possible. +As nextpnr allows arbitrary constraints on bels for more advanced packer-free flows and complex real-world architectures; placements must be checked for legality using `isBelLocationValid` (after placement) and the placement rejected if invalid. For analytical placement algorithms; after creating a spread-out AP solution the legality of placing each cell needs to be checked. In practice, the cost of this is fairly low as the architecture should ensure these functions are as fast as possible. There are several routes for timing information in the placer: - sink `PortRef`s have a `budget` value annotated by calling `assign_budget` which is an estimate of the maximum delay that an arc may have |