[Synth] Add GenericLUTMapper pass for LUT mapping #8888
Merged
Conversation
This file contains hidden or bidirectional Unicode text that may be interpreted or compiled differently than what appears below. To review, open the file in an editor that reveals hidden Unicode characters.
Learn more about bidirectional Unicode characters
This commit introduces a new synthesis pass that performs technology-independent LUT mapping from AIG representation to generic lookup tables. The pass is primarily designed for benchmarking purposes and provides functionality equivalent to ABC's `if -K 6` command for K-LUT mapping. The pass supports configurable LUT sizes and uses a cut-based rewriting approach to efficiently map combinational logic from AIG nodes to truth tables. It includes options for maximum LUT size and maximum cuts per root node to control the mapping quality and compilation time. The implementation provides technology-independent LUT mapping with configurable K-LUT support (default K=6), cut enumeration with configurable limits, truth table generation for optimal LUT utilization, and seamless integration with the existing synthesis pipeline. This enables efficient FPGA synthesis flows by providing a clean mapping from optimized AIG representations to generic LUT structures that can be further processed by technology-specific mappers, while also serving as a benchmarking tool to compare synthesis results.
a7e4065 to
2076fe7
Compare
fabianschuiki
approved these changes
Aug 25, 2025
Comment on lines
+59
to
+64
| // LUT: hw.module @mul | ||
| // LUT: comb.truth_table | ||
| // LUT-NOT: aig.and_inv | ||
| // LUT-NOT: comb.and | ||
| // LUT-NOT: comb.xor | ||
| // LUT-NOT: hw.instance |
There was a problem hiding this comment.
I love how much the LEC tool simplifies these synthesis tests 😅
There was a problem hiding this comment.
Yeah otherwise it's impossible to keep correctness...
Comment on lines
+592
to
+594
| // If the pattern does not provide NPN classes, we use a special key | ||
| // to indicate that it should be considered for all cuts. | ||
| nonTruthTablePatterns.push_back(pattern.get()); |
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
2 participants
Add this suggestion to a batch that can be applied as a single commit.
This suggestion is invalid because no changes were made to the code.
Suggestions cannot be applied while the pull request is closed.
Suggestions cannot be applied while viewing a subset of changes.
Only one suggestion per line can be applied in a batch.
Add this suggestion to a batch that can be applied as a single commit.
Applying suggestions on deleted lines is not supported.
You must change the existing code in this line in order to create a valid suggestion.
Outdated suggestions cannot be applied.
This suggestion has been applied or marked resolved.
Suggestions cannot be applied from pending reviews.
Suggestions cannot be applied on multi-line comments.
Suggestions cannot be applied while the pull request is queued to merge.
Suggestion cannot be applied right now. Please check back later.
This is a follow-up to #8868.
This commit introduces a pass that performs technology-independent LUT mapping from logic network to generic lookup tables (comb.truth_table). The pass is primarily designed for benchmarking purposes and provides functionality equivalent to ABC's
if -K 6command for K-LUT mapping.The pass supports configurable LUT sizes and uses a cut-based rewriting approach to efficiently map combinational logic from AIG nodes to truth tables. It includes options for maximum LUT size and maximum cuts per root node to control the mapping quality and compilation time. The implementation provides technology-independent LUT mapping with configurable K-LUT support (default K=6), cut enumeration with configurable limits, truth table generation for optimal LUT utilization, and seamless integration with the existing synthesis pipeline.