Hint const in loops

Set const hints on statements inside preserved scf.For bodies.

The standard kirin pipeline runs const.Propagate once at the top-level method scope, so SSA values inside preserved scf.For bodies don't pick up const hints. This module fills that gap with a generic rule that mimics const.Propagate's pure-fallback logic (run each Pure statement's concrete impl on its const-hinted args, stamp the result back as a const hint), plus a few specialized rules for cases that need static-type info or scf.For-aware traversal.

HintConstInLoops `dataclass`

HintConstInLoops()

Bases: Pass


              flowchart TD
              bloqade.stim.passes.hint_const_in_loops.HintConstInLoops[HintConstInLoops]

              

              click bloqade.stim.passes.hint_const_in_loops.HintConstInLoops href "" "bloqade.stim.passes.hint_const_in_loops.HintConstInLoops"

Pass that sets const hints inside preserved scf.For loop bodies.

Composes PropagateInitializerHints (for For-level hint/type propagation) with per-statement hinting rules (HintConstant, HintTupleNew, etc.). Also installs the early-terminating constprop override for scf.For.

HintLen

Bases: RewriteRule


              flowchart TD
              bloqade.stim.passes.hint_const_in_loops.HintLen[HintLen]

              

              click bloqade.stim.passes.hint_const_in_loops.HintLen href "" "bloqade.stim.passes.hint_const_in_loops.HintLen"

Hint py.Len results as const from static IList type info.

Kept distinct from HintPureFromConcrete because the length comes from the operand's type (IList[X, Literal(N)]), not from a const-hinted operand value — useful when the IList itself isn't const but its length is statically known.

HintPureFromConcrete `dataclass`

HintPureFromConcrete(dialects: DialectGroup)

Bases: RewriteRule


              flowchart TD
              bloqade.stim.passes.hint_const_in_loops.HintPureFromConcrete[HintPureFromConcrete]

              

              click bloqade.stim.passes.hint_const_in_loops.HintPureFromConcrete href "" "bloqade.stim.passes.hint_const_in_loops.HintPureFromConcrete"

Generic const-folder mimicking const.Propagate's pure fallback.

For any Pure statement whose args all carry const.Value hints, run the concrete impl on the const data and stamp each result with a const.Value hint. Subsumes per-stmt hand-rolled folders for Constant, TupleNew, IListNew, Range, Slice, USub, and similar.

PropagateBodyArgTypes

Bases: RewriteRule


              flowchart TD
              bloqade.stim.passes.hint_const_in_loops.PropagateBodyArgTypes[PropagateBodyArgTypes]

              

              click bloqade.stim.passes.hint_const_in_loops.PropagateBodyArgTypes href "" "bloqade.stim.passes.hint_const_in_loops.PropagateBodyArgTypes"

For preserved scf.For loops where an iter_arg follows the concat accumulator pattern (acc = acc + ms or acc = ms + acc), refine the body block arg's type to IList[ms_elem_type, Any] and propagate through in-body uses. Enables partial rewrites to recognize fixed-size list literals and REPEAT-faithful slices derived from the accumulator (e.g., [acc[-1]], acc[-2:]).

PropagateInitializerHints

Bases: RewriteRule


              flowchart TD
              bloqade.stim.passes.hint_const_in_loops.PropagateInitializerHints[PropagateInitializerHints]

              

              click bloqade.stim.passes.hint_const_in_loops.PropagateInitializerHints href "" "bloqade.stim.passes.hint_const_in_loops.PropagateInitializerHints"

Propagate hints and types from For loop initializers to body block args and results.

Only applies to REPEAT-eligible For loops. Also propagates types through downstream GetItem and ilist.New use chains.

Hint const in loops