srdatalog.ir.dialects.relation.d2l.ops

relation.d2l ops — Device2LevelIndex segment-aware nodes.

D2L FULL_VER reads expose two view slots (HEAD + FULL); operators that consume them have to visit both segments. The legacy emitter does this with a for (_seg = 0; _seg < view_count; ...) loop wrapping the join body, reassigning the view variable per iteration. D2lSegmentLoop captures that pattern as a first-class IIR op.

See also relation.d2l.__init__.view_count for the per-source slot arithmetic.

Module Contents

Classes

D2lSegmentLoop

Iterate over a D2L source’s segments (HEAD then FULL).

Data

__all__

API

class srdatalog.ir.dialects.relation.d2l.ops.D2lSegmentLoop[source]

Bases: srdatalog.ir.core.Op

Iterate over a D2L source’s segments (HEAD then FULL).

Two emit shapes:

Single-line (multi-source nested CJ — legacy _nested_column_join_multi): when local_view_var == '', lowers to

for (int <seg_var> = 0; <seg_var> < <view_count>; <seg_var>++) {
  [auto ]<view_var> = views[<base_slot> + <seg_var>];
  <body>
}

declare=False rebinds the kernel-start view_var; declare=True declares a fresh per-segment view (single-source nested CJ case, N5.3).

Two-line (root CJ multi non-first source — legacy _root_cj_multi phase 2): when local_view_var is non-empty, lowers to

for (int <seg_var> = 0; <seg_var> < <view_count>; <seg_var>++) {
  auto <local_view_var> = views[<base_slot> + <seg_var>];
  <view_var> = <local_view_var>;
  <body>
}

The local var is the SHORT name (view_<rel>_<src_idx>) the immediately-following prefix narrowing references; the fixed canonical kernel-start view is rebound so downstream code that uses the LONG name also sees the current segment’s array. The assignment line is omitted when local_view_var == view_var (matches legacy if fixed_view_var != view_var guard).

Indent semantics (both shapes): the wrapped body emits at one level deeper than the segment loop’s for preamble, but EmitCtx.segment_depth is bumped so any inner IntersectIter anchors its body lines / body op back to the outer indent — matching the legacy seg_indent-vs-ind(ctx) indent quirk.

base_slot: int

None

body: srdatalog.ir.core.Op

None

declare: bool

None

local_view_var: str

None

seg_var: str

None

view_count: int

None

view_var: str

None

srdatalog.ir.dialects.relation.d2l.ops.__all__

[‘D2lSegmentLoop’]