[LLHD] Add llhd.sig.extract support to Mem2Reg #8542
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
Extend LLHD's Mem2Reg pass to support `llhd.sig.extract` projections. To implement the extraction and injection of bit ranges at dynamic offsets, add a few helper functions to `CombOps.h` that assemble the necessary operations. We may want to add a `comb.inject` op in the future to simplify this.
maerhart
approved these changes
Jun 6, 2025
| #include "mlir/IR/PatternMatch.h" | ||
| #include "llvm/Support/FormatVariadic.h" | ||
|
|
||
| using namespace circt; | ||
| using namespace comb; | ||
|
|
||
| Value comb::createZExt(OpBuilder &builder, Location loc, Value value, | ||
| unsigned targetWidth) { | ||
| assert(value.getType().isInteger()); |
There was a problem hiding this comment.
Nit: could also use isSignlessInteger() as comb only uses signless
| return builder.createOrFold<comb::OrOp>(loc, value, replacement, twoState); | ||
| } | ||
|
|
||
| Value comb::createInject(OpBuilder &builder, Location loc, Value value, |
There was a problem hiding this comment.
This function doesn't have a test or am I missing something?
| if (end < largeWidth) | ||
| fragments.push_back( | ||
| builder.create<comb::ExtractOp>(loc, value, end, largeWidth - end)); | ||
| fragments.push_back(replacement); |
There was a problem hiding this comment.
What if end > largeWidth? Should we extract from replacement and ignore the non-overlapping part?
Sign up for free
to join this conversation on GitHub.
Already have an account?
Sign in to comment
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Outdated suggestions cannot be applied.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.
Extend LLHD's Mem2Reg pass to support
llhd.sig.extractprojections. To implement the extraction and injection of bit ranges at dynamic offsets, add a few helper functions toCombOps.hthat assemble the necessary operations. We may want to add acomb.injectop in the future to simplify this.