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Track adding control flow passes for optimization level 1
See original GitHub issueWhat should we add?
This issue is to track the target set of passes to enable control flow handling for transpiler optimization_level=1.
- SetLayout (no change)
- TrivialLayout (no change)
- DenseLayout (#8742)
- EnlargeWithAncilla (no change)
- FullAncillaAllocation (no change)
- ApplyLayout (no change)
- VF2Layout (#8804)
- VF2PostLayout (#8804)
- CheckMap (#8793 )
- CheckGateDirection (#8822)
- GateDirection (#8822)
- StochasticSwap (#8418)
- ContainsInstruction (#8763)
- GatesInBasis (#8823)
- UnitarySynthesis (#8565 )
- Unroll3qOrMore (#8752 )
- UnrollCustomDefinitions (#8752)
- BasisTranslator(#7808)
- BarrierBeforeFinalMeasurements (no change)
- Depth (#8763)
- FixedPoint (no changes)
- Size (#8763)
- Optimize1qGatesDecomposition (#8766)
- CXCancellation (#8752)
- RemoveResetInZeroState (no change required)
We also need to update the preset pass managers (esp level 1) to suitably modify the defaults / reject scheduling_method != None if a given circuit has control flow:
- Update preset pass managers (#8830)
Time permitting:
- SabreSwap
- SabreLayout
- Layout2qDistance - we elected to swap the O1 PM to use
CheckMapinstead, to avoid adding the questionable “weighting” of control-flow blocks to another pass (#8733)
Issue Analytics
- State:
- Created a year ago
- Reactions:1
- Comments:7 (7 by maintainers)
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I’ll handle all the trivial passes in a PR that I’ll post tomorrow.
Just a note:
BarrierBeforeFinalMeasuredoesn’t need to recurse in, because any measurements in a control-flow block can’t be final measurements by the original definition.ResetInZeroStatecan’t trivially recurse, because the start of a block cannot be assumed to be zero.I found some more transpiler passes while trying to update the preset pass managers, so I’ve added them to the list.