perf: split append attribution

.phrase/phases/phase-kp-overhaul-20260726/change_post_audit_hardening_20260820.md

@@ -66,6 +66,18 @@
   yet because the measured DP/append owners require an exact redesign.
 - **Commit:** `db6e6b9`.
 
+## 2026-08-20 — Split append preparation, assembly, and DP timings
+
+- **Modify** the evaluator to time `ekp--append-para` and
+  `ekp--layout-plan-from-para` independently, fixing a wrapper-name collision
+  found by the first red run.
+- **Evidence:** latest source-fresh candidate p95 is C append/append-DP
+  16.953/1.015 ms and Elisp append/append-DP 71.896/55.970 ms; both engines
+  spend about 9.753 ms in append preparation and 5.663 ms in plan assembly.
+  The report remains red, raw JSONL is nonempty, and the wrapper itself now
+  passes the same matrix without argument errors.
+- **Commit:** Pending measurement commit.
+
 ## Verification
 
 - Source-first normal ERT: 295/295.

.phrase/phases/phase-kp-overhaul-20260726/task_post_audit_hardening_20260820.md

@@ -59,3 +59,7 @@
     nonempty raw JSONL per run. Current source-fresh p95 is 17.161/1.187 ms
     for C append/append-DP and 73.293/57.063 ms for Elisp; choose a
     production optimization only after this attribution remains stable.
+  - It now also records append preparation/assembly separately: latest p95
+    is 9.753/5.663 ms for both engines, while Elisp append-DP is 55.970 ms
+    and C append-DP is 1.015 ms. The evaluator wrapper collision was fixed and
+    the same source matrix passes the harness without argument errors.

postmortem/20260820-source-fresh-live-commit-gate.md

@@ -35,6 +35,11 @@ one-line optimization. A broad DP or projection rewrite would need a new
 red/green parity matrix and architecture decision; it is not smuggled into
 this measurement change.
 
+The finer attribution separates the latest source-fresh append p95 into
+`append_para`/`append_plan`: C 9.753/5.663 ms and Elisp 9.753/5.663 ms. The
+Elisp `append_dp` remains 55.970 ms; C `append_dp` remains 1.015 ms. This is
+why a C-only change cannot close the locked gate.
+
 ## Consequences
 
 - `issue028` is closed as an evaluator-integrity defect.

tests/ekp-live-commit-evaluator.el

@@ -51,6 +51,8 @@
 (defvar ekp-live-commit-evaluator--dp-ms 0.0)
 (defvar ekp-live-commit-evaluator--append-ms 0.0)
 (defvar ekp-live-commit-evaluator--append-dp-ms 0.0)
+(defvar ekp-live-commit-evaluator--append-para-ms 0.0)
+(defvar ekp-live-commit-evaluator--append-plan-ms 0.0)
 (defvar ekp-live-commit-evaluator--module-ms 0.0)
 (defvar ekp-live-commit-evaluator--install-ms 0.0)
 (defvar ekp-live-commit-evaluator--clear-ms 0.0)
@@ -99,6 +101,8 @@
         ekp-live-commit-evaluator--dp-ms 0.0
         ekp-live-commit-evaluator--append-ms 0.0
         ekp-live-commit-evaluator--append-dp-ms 0.0
+        ekp-live-commit-evaluator--append-para-ms 0.0
+        ekp-live-commit-evaluator--append-plan-ms 0.0
         ekp-live-commit-evaluator--module-ms 0.0
         ekp-live-commit-evaluator--install-ms 0.0
         ekp-live-commit-evaluator--clear-ms 0.0
@@ -171,6 +175,8 @@
         (para (symbol-function 'ekp--get-para))
         (dp (symbol-function 'ekp--dp-cache-para))
         (append-dp (symbol-function 'ekp--dp-cache-append))
+        (append-para (symbol-function 'ekp--append-para))
+        (append-layout (symbol-function 'ekp--layout-plan-from-para))
         (module (symbol-function 'ekp-c-break-with-arrays))
         (install (symbol-function 'ekp-buffer--install-live-prefix))
         (suffix (symbol-function 'ekp-buffer--clear-live-suffix))
@@ -199,6 +205,12 @@
          ((symbol-function 'ekp--dp-cache-append)
           (ekp-live-commit-evaluator--timed-wrapper
            'ekp-live-commit-evaluator--append-dp-ms nil append-dp))
+         ((symbol-function 'ekp--append-para)
+          (ekp-live-commit-evaluator--timed-wrapper
+           'ekp-live-commit-evaluator--append-para-ms nil append-para))
+         ((symbol-function 'ekp--layout-plan-from-para)
+          (ekp-live-commit-evaluator--timed-wrapper
+           'ekp-live-commit-evaluator--append-plan-ms nil append-layout))
          ((symbol-function 'ekp-c-break-with-arrays)
           (ekp-live-commit-evaluator--timed-wrapper
            'ekp-live-commit-evaluator--module-ms
@@ -257,6 +269,8 @@
          (dp_ms . ,ekp-live-commit-evaluator--dp-ms)
          (append_ms . ,ekp-live-commit-evaluator--append-ms)
          (append_dp_ms . ,ekp-live-commit-evaluator--append-dp-ms)
+         (append_para_ms . ,ekp-live-commit-evaluator--append-para-ms)
+         (append_plan_ms . ,ekp-live-commit-evaluator--append-plan-ms)
          (module_ms . ,ekp-live-commit-evaluator--module-ms)
          (publication_ms
           . ,(+ ekp-live-commit-evaluator--install-ms
@@ -489,6 +503,10 @@
                                baseline 'append_ms))
                    (append_dp . ,(ekp-live-commit-evaluator--statistics
                                   baseline 'append_dp_ms))
+                   (append_para . ,(ekp-live-commit-evaluator--statistics
+                                    baseline 'append_para_ms))
+                   (append_plan . ,(ekp-live-commit-evaluator--statistics
+                                    baseline 'append_plan_ms))
                    (module . ,(ekp-live-commit-evaluator--statistics
                                baseline 'module_ms))
                    (publication
@@ -509,6 +527,10 @@
                                 candidate 'append_ms))
                     (append_dp . ,(ekp-live-commit-evaluator--statistics
                                    candidate 'append_dp_ms))
+                    (append_para . ,(ekp-live-commit-evaluator--statistics
+                                     candidate 'append_para_ms))
+                    (append_plan . ,(ekp-live-commit-evaluator--statistics
+                                     candidate 'append_plan_ms))
                     (module . ,(ekp-live-commit-evaluator--statistics
                                 candidate 'module_ms))
                     (publication