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perf(FiveSql2): PcOpFieldTrim fused peephole — string WHERE at raw RDD parity

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Second pcode peephole to match the one added for FieldGet(literal).
SqlExprToPrg auto-wraps CHAR column references with AllTrim() to
match SqlCmpEq's CHAR-padding trim semantics, so every string WHERE
predicate evaluates `AllTrim(FieldGet(n)) == 'literal'` per row.

Before this commit each of those per-row evaluations did:
  1. PushSymbol ALLTRIM
  2. PushSymbol FIELDGET → Function(1)  [1 RTL Frame]
  3. parseCharField → MakeString       [alloc: copies raw bytes]
  4. Function(1) → AllTrim RTL         [1 RTL Frame]
  5. strings.TrimSpace                  [alloc: new string]
  6. Return, continue

New opcode `PcOpFieldTrim <idx>` (0x47) fuses the two RTL calls into
a single opcode that:
  1. Calls FastFieldGetter directly (no Frame/Function dispatch).
  2. Walks the returned string with ASCII-space trim in place.
  3. Pushes `s[lo:hi]` — a sub-slice, no new allocation.
  4. Short-circuits back to the same string if no trim needed.

genpc recognizes the shape `AllTrim(FieldGet(<int-literal>))` in
emitCall and emits the fused opcode automatically — no SQL-side
API change. Matches the existing FieldGet peephole's shape.

Bench impact (50k rows, 3-run steady state, vs raw RDD baseline 6.2ms):

  String WHERE          before 7.9ms → after 6.2ms   1.00x (parity!)
  Numeric WHERE         6.9ms (unchanged)            1.11x
  No WHERE              9.1ms (unchanged)            1.47x

String WHERE is now at parity with the raw Harbour-style RDD scan.
Compared to session start (119ms), that's a 19x speedup.

Validation:
  - FiveSql2 43/43
  - Harbour compat 51/51
  - go test ./... ALL PASS

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>
This commit is contained in:
CharlesKWON
2026-04-14 14:03:03 +09:00
parent af9e965bc6
commit b1d89b9783
3 changed files with 60 additions and 0 deletions
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6
hbrt/pcode.go
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@@ -74,6 +74,12 @@ const (
// peephole optimization. Operand: uint16 1-based field position.
PcOpFieldGet byte = 0x46
// `AllTrim(FieldGet(n))` peephole — fetch the field, trim the
// result in place, push one string. Skips two Function dispatches
// (FieldGet + AllTrim) and one intermediate string allocation
// per invocation. Operand: uint16 1-based field position.
PcOpFieldTrim byte = 0x47
// Self / OOP
PcOpPushSelf byte = 0x48
PcOpPushSelfField byte = 0x49 // + uint16 len + name