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[Seq] Remove redundant enable mux in front of compreg.ce #8477

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Merged
merged 1 commit into from
May 12, 2025
Merged

[Seq] Remove redundant enable mux in front of compreg.ce #8477

merged 1 commit into from
May 12, 2025

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fabianschuiki
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Add a canonicalizer that removes comb.mux and arith.select ops on the data input of the register if those ops use the register's enable as select operand. For example:

%0 = comb.mux %enable, %a, %b
seq.compreg.ce %0, %clock, %enable

gets canonicalized to

seq.compreg.ce %a, %clock, %enable

@fabianschuiki
[Seq] Remove redundant enable mux in front of compreg.ce
28c13c3 
Add a canonicalizer that removes `comb.mux` and `arith.select` ops on
the data input of the register if those ops use the register's enable as
select operand. For example:

    %0 = comb.mux %enable, %a, %b
    seq.compreg.ce %0, %clock, %enable

gets canonicalized to

    seq.compreg.ce %a, %clock, %enable
@fabianschuiki fabianschuiki requested review from teqdruid and uenoku May 12, 2025 19:17
@fabianschuiki fabianschuiki added the Seq Involving the `seq` dialect label May 12, 2025
uenoku
uenoku approved these changes May 12, 2025
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LGTM

@fabianschuiki fabianschuiki merged commit b70b2bb into main May 12, 2025
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@fabianschuiki fabianschuiki deleted the fschuiki/compregce-drop-mux branch May 12, 2025 21:55
TaoBi22 pushed a commit to TaoBi22/circt that referenced this pull request Jul 17, 2025
@fabianschuiki @TaoBi22
[Seq] Remove redundant enable mux in front of compreg.ce (llvm#8477)
e697e05 
Add a canonicalizer that removes `comb.mux` and `arith.select` ops on
the data input of the register if those ops use the register's enable as
select operand. For example:

    %0 = comb.mux %enable, %a, %b
    seq.compreg.ce %0, %clock, %enable

gets canonicalized to

    seq.compreg.ce %a, %clock, %enable
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@teqdruid teqdruid teqdruid approved these changes

@uenoku uenoku uenoku approved these changes

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@fabianschuiki @teqdruid @uenoku