Fix sx resynthesis of negative angles in CommutativeCancellation (backport #16599)#16615
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…16599) * Fix `sx` resynthesis of negative angles in `CommutativeCancellation` `%` maintains the sign of the left operand, so `0..(num_sx as i64 % 4)` is an empty iterator for non-positive `num_sx`. If the calculated rotation angle was negative (such as from a chain of `sxdg`), non-identity, and we go down the `sx`-like synthesis path, we would miscompile. This is a minimal fix to be backport stable, rather than a greater reworking. Introduced in 91081cc: Add additional Z and X rotation gate handling to CommutativeCancellation (#16191) * Use `ddt` test parametrisaion (cherry picked from commit 33d90a9)
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%maintains the sign of the left operand, so0..(num_sx as i64 % 4)is an empty iterator for non-positivenum_sx. If the calculated rotation angle was negative (such as from a chain ofsxdg), non-identity, and we go down thesx-like synthesis path, we would miscompile.This is a minimal fix to be backport stable, rather than a greater reworking.
Introduced in 91081cc: Add additional Z and X rotation gate handling to CommutativeCancellation (#16191)
Fix #16594
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This is an automatic backport of pull request #16599 done by [Mergify](https://mergify.com).