Allow division and modulo operations on fixed-width bit (unsinged) types - #1414
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Allow division and modulo operations on fixed-width bit (unsinged) types#1414jaehyun1ee wants to merge 3 commits into
jaehyun1ee wants to merge 3 commits into
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Signed-off-by: jaehyun1ee <99jaehyunlee@kaist.ac.kr>
jafingerhut
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May 29, 2026
| and is computed by truncating the result to the output's width. | ||
| P4 architectures may impose additional restrictions --- e.g., they may only | ||
| allow multiplication by a non-negative integer power of two. | ||
| * Truncating integer division between positive values, denoted by `/`. |
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The numerator for division or modulo should be allowed to be 0, not only positive, yes? I agree it is reasonable to require the denominator to be positive, and not attempt to define the result of such an operation with a denominator of 0.
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Thank you for the suggestion, I made the following edit:
* Truncating integer division, denoted by `/`.
The denominator must be positive.
Signed-off-by: jaehyun1ee <99jaehyunlee@kaist.ac.kr>
Signed-off-by: jaehyun1ee <99jaehyunlee@kaist.ac.kr>
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This is a follow-up PR from #1327.
The current specification only allows division and modulo for arbitrary-precision integer types (
int), but not forbit<W>orint<S>types. Yet, there were uses of division and modulo onbit<W>andint<S>types in p4c tests (where p4c allows such, under certain p4c-specific restrictions).This was first discussed in Nov-2025 LDWG meeting, where @jonathan-dilorenzo summarized as:
However, no follow-up PR was made, thus this has gone through another round of discussion in May-2026 LDWG meeting. The consensus is the same: allow division and modulo for
bit<W>types, yet disallow forint<S>types since there is no clear consensus on how division and modulo should be defined regarding signedness and rounding.This PR adds division and modulo to 8.7. Operations on fixed-width bit types (unsigned integers), also mentioning that P4 architectures may restrict division and modulo.