FLOOR-COST-500MS: one home for the persisted frontier standing, and the absent arm of the share measurement

dag/gunbc/compiler_frontend_program_status.dag

@@ -33,8 +33,7 @@ import gunbc.self_host_compile_phase_frontier {
   CompilePhaseFrontierEmpty,
   CompilePhaseFrontierValidated,
   CompilePhaseFrontierInvalid,
-  compile_phase_frontier_standing,
-  self_host_compile_phase_frontier_receipts,
+  current_compile_phase_frontier_standing,
   self_host_compile_phase_ratchet_enrolment,
 }
 import v2.compiler.self_host.stage0_crate_layout { emitter_produced_divergent_registrations }
@@ -424,7 +423,7 @@ fn stage_subject_outstanding(stage: NamespaceCutStage) -> List<String> {
 fn milestone_status(m: ProgramMilestone) -> MilestoneStanding {
   match m {
     SelfHostWholeCorpusPopulationDerived =>
-      match compile_phase_frontier_standing(series: self_host_compile_phase_frontier_receipts) {
+      match current_compile_phase_frontier_standing() {
         CompilePhaseFrontierValidated { latest } => standing_from_evidence(e: observe_outstanding(
           subject: "self-host S2: whole-corpus compile-phase population derived from the latest validated frontier receipt" as NonEmptyStr,
           outstanding: if latest.board.partition_complete { [] } else { latest.unplaced_identities }
@@ -497,7 +496,7 @@ fn milestone_status(m: ProgramMilestone) -> MilestoneStanding {
         )
       )
     SelfHostCorpusEmitsCleanly =>
-      match compile_phase_frontier_standing(series: self_host_compile_phase_frontier_receipts) {
+      match current_compile_phase_frontier_standing() {
         CompilePhaseFrontierValidated { latest } => standing_from_evidence(e: observe_outstanding(
           subject: "self-host: error diagnostics in the latest validated whole-corpus compile-phase receipt (coded and codeless)" as NonEmptyStr,
           outstanding: latest.raw_error_diagnostic_identities

dag/gunbc/design_ledgers.dag

@@ -80,9 +80,8 @@ import gunbc.self_host_compile_phase_frontier {
   CompilePhaseFrontierEmpty,
   CompilePhaseFrontierValidated,
   CompilePhaseFrontierInvalid,
-  compile_phase_frontier_standing,
+  current_compile_phase_frontier_standing,
   render_phase_board,
-  self_host_compile_phase_frontier_receipts,
 }
 
 fn h1(text: String) -> MarkdownBlock { HeadingBlock { level: H1, inlines: [TextInline { text: text }] } }
@@ -138,7 +137,7 @@ fn failure_mode_document() -> MarkdownDocument {
 }
 
 fn compile_phase_frontier_blocks() -> List<MarkdownBlock> {
-  match compile_phase_frontier_standing(series: self_host_compile_phase_frontier_receipts) {
+  match current_compile_phase_frontier_standing() {
     CompilePhaseFrontierEmpty => [
       h3(text: "Whole-corpus compile-phase frontier receipts"),
       p(text: "No complete instrument observation has been appended; the next valid row must be the typed genesis receipt."),

dag/gunbc/instruments/compile_phase_frontier_live_gate.dag

@@ -9,7 +9,7 @@ import extdeps.cargo_build
 import gunbc.self_host_compile_phase_frontier {
   TargetPinnedOnInvocation,
   CompilePhaseInvocation,
-  self_host_compile_phase_frontier_receipts
+  current_compile_phase_frontier_standing
 }
 import extdeps.languages.rust.compiler_phases { rustc_phase_classification_policy_digest }
 import gunbc.self_host_compile_phase_live_gate {
@@ -142,7 +142,7 @@ fn write_gate_report(report: String, m: EmissionMeasurement, verdict_text: Strin
 // only other constructor for an observation does not exist.
 fn adjudicate(report: String, m: EmissionMeasurement, reading: LiveToolchainReading) -> ProcessExit {
   let verdict = live_tree_verdict_for_measurement(
-    series: self_host_compile_phase_frontier_receipts,
+    standing: current_compile_phase_frontier_standing(),
     m: m,
     toolchain: reading
   )

dag/gunbc/self_host_compile_phase_frontier.dag

@@ -1283,6 +1283,35 @@ fn compile_phase_frontier_standing(series: List<CompilePhaseFrontierReceipt>) ->
   }
 }
 
+// THE STANDING OF THE PERSISTED SERIES -- one authority for the question five call sites were
+// each spelling out.
+//
+// WHY IT EXISTS AS A DECLARATION RATHER THAN AS A REPEATED ARGUMENT. `compile_phase_frontier_standing`
+// is general in its series: it judges ANY series of receipts, which is what its own witnesses
+// exercise with perturbed fixtures. But there is only ONE persisted series in this repository, and
+// "the standing of THAT series" is a distinct, singular fact that this module owns. Spelling the
+// pairing at every consumer made the fact positional -- five sites each re-asserting the join --
+// and DESIGN section 3 puts one fact in one place. Consumers that judge a HYPOTHETICAL series keep
+// calling the general function directly; that distinction is the whole reason both spellings stay.
+//
+// THE COST CONSEQUENCE IS A CONSEQUENCE AND NOT THE REASON, but it is why the rewire happened now.
+// The required floor builds a fresh evaluation frame per claim, so the eval-frame memo dies at
+// every claim boundary and each claim re-derived this standing from scratch. Measured on main run
+// 33664768371's `required_floor_cross_claim_demand.tsv`: 22 claims, 36 evaluations, 6508ms
+// inclusive-of-callees, with `phase_board_series_ratchet` (23/23) and `apply_regression_transition`
+// (23/23) nested underneath it. Being NULLARY, this declaration is preparation-forceable, so
+// `v2.workflow.floor_pure_producer_share` can serve it as a WARM row with an empty argument row --
+// no per-serve argument reification of the receipt series at all, which is the cost shape that
+// disqualified earlier candidates from that roster. THAT IS A PROPERTY OF THIS DECLARATION AND NOT
+// A CLAIM THAT A ROW EXISTS: no roster row is enrolled here, and the enrolment is held pending a
+// present-vs-absent measurement on a tree that includes gunbc#10133, which made the recompute side
+// of that comparison cheaper and so moved the denominator the earlier receipt was measured against.
+// The census figures above predate it for the same reason. Re-derive with the instruments the
+// roster names, never from these sentences.
+fn current_compile_phase_frontier_standing() -> CompilePhaseFrontierStanding {
+  compile_phase_frontier_standing(series: self_host_compile_phase_frontier_receipts)
+}
+
 // THE RATCHET ABOVE JUDGES RECEIPTS AGAINST EACH OTHER, AND NOTHING IN IT LOOKS AT THE TREE BEING
 // MERGED. compile_phase_frontier_standing answers Validated{latest} from the persisted series
 // alone, so its verdict is a claim about the TREE THE LATEST RECEIPT NAMES -- a past tree by

dag/gunbc/self_host_compile_phase_live_gate.dag

@@ -256,14 +256,14 @@ fn live_observation_from_measurement(
 // The verdict for a measurement, which is the only entry point a consumer should use: it cannot be
 // handed an observation that no measurement produced.
 fn live_tree_verdict_for_measurement(
-  series: List<CompilePhaseFrontierReceipt>,
+  standing: CompilePhaseFrontierStanding,
   m: EmissionMeasurement,
   toolchain: LiveToolchainReading
 ) -> LiveFrontierVerdict {
   match live_observation_from_measurement(m: m, toolchain: toolchain) {
     LiveObservationNotTaken { cause: why } => LiveFrontierUnmeasured { reason: why }
     LiveObservationTaken { observation: observation } =>
-      live_tree_frontier_verdict(series: series, observation: observation)
+      live_tree_frontier_verdict(standing: standing, observation: observation)
   }
 }
 
@@ -279,11 +279,28 @@ fn live_phase_board(observation: LiveCompilePhaseObservation) -> PersistedPhaseB
 // board; a live tree carries no such authored disposition, so any identity the live board holds
 // and the latest receipt does not refuses here. The remedy is to append a receipt -- to make the
 // exposure a declared, checked fact -- and not to teach this gate to guess a cause.
+// THE PARAMETER IS THE STANDING AND NOT THE SERIES, and the distinction is the difference between
+// a parameter the body consumes and a parameter it merely passes through. Every use of `series`
+// below was one call to `compile_phase_frontier_standing`; nothing else in this fold ever looked at
+// a receipt list. Taking the series therefore declared a dependency wider than the body has, and
+// the width was not free: it forced the fold to be RE-DERIVED at every call even when every caller
+// meant the same persisted series, because the shared value was one level inside the parameter
+// rather than being the parameter.
+//
+// TAKING THE STANDING KEEPS EVERY CALLER HONEST IN BOTH DIRECTIONS. A caller judging the live tree
+// against THE persisted frontier passes `current_compile_phase_frontier_standing()`, which names
+// that subject exactly and is servable across claim frames. A caller judging a PERTURBED series --
+// which is what this module's witnesses exist to do -- passes
+// `compile_phase_frontier_standing(series: <perturbed>)` and gets a genuine re-derivation, because
+// its subject genuinely differs. Neither spelling can be mistaken for the other at a call site,
+// which the old signature could not say: `series: self_host_compile_phase_frontier_receipts` and
+// `series: self_host_compile_phase_frontier_receipts |> skip(n: 1)` are one character apart and
+// mean entirely different subjects.
 fn live_tree_frontier_verdict(
-  series: List<CompilePhaseFrontierReceipt>,
+  standing: CompilePhaseFrontierStanding,
   observation: LiveCompilePhaseObservation
 ) -> LiveFrontierVerdict {
-  match compile_phase_frontier_standing(series: series) {
+  match standing {
     CompilePhaseFrontierInvalid { reason: why } => LiveFrontierRefused {
       identities: [],
       reason: concat(

dag/test/claim/self_host_compile_phase_frontier_witness_test.dag

@@ -37,7 +37,6 @@ import gunbc.self_host_compile_phase_frontier {
   PhaseBoardSeriesRefused,
   ExposedByPhaseAdvance,
   PhaseBoardSeriesHeld,
-  phase_board_series_ratchet,
   self_host_compile_phase_frontier_receipts,
   PersistedPhaseBoardFold,
   phase_board_from_census_identities,
@@ -53,6 +52,7 @@ import gunbc.self_host_compile_phase_frontier {
   board_row,
   CompilePhaseFrontierValidated,
   compile_phase_frontier_standing,
+  current_compile_phase_frontier_standing,
   CompilePhaseFrontierCoverage,
   FrontierCoversSubjectTree,
   FrontierReceiptTreeStale,
@@ -180,10 +180,41 @@ fn fixture_board(resolve_ids: List<String>, typeck_ids: List<String>) -> RustcPh
 // The required witness executes over the persisted series, not a fixture or a copied count. The
 // genesis is the only row today; once a successor is appended this same call validates the link and
 // applies the phase/identity ratchet to the latest validated pair.
+// ASKED THROUGH THE STANDING RATHER THAN THROUGH THE RATCHET, and the two are not the same
+// question by a hair: `CompilePhaseFrontierValidated` is `PhaseBoardSeriesHeld` AND a latest
+// receipt existing, so this asserts strictly MORE than it did. The extra conjunct cannot go green
+// where the old one went red -- a held series with no latest would now refuse here, which is the
+// fail-closed direction.
+//
+// IT ALSO STOPS BEING THE MOST EXPENSIVE ROW IN THE CORPUS. Asking the ratchet directly re-derived
+// the whole fold in this claim's own frame; asking the standing reads the value
+// `v2.workflow.floor_pure_producer_share` already holds. Measured on this branch: 427ms on the
+// absent arm and 461ms with the share enrolled but this row still folding for itself -- the single
+// highest row in a 3499-row corpus at 92% of the 500ms ceiling.
+//
+// WHAT THIS ROW NOW TRUSTS, STATED PRECISELY, BECAUSE AN EARLIER REVISION OF THIS COMMENT OVERCLAIMED
+// IT. It said this row's safety rested on
+// `the_persisted_standing_accessor_agrees_with_the_general_fold_on_the_named_series` acting as the
+// corpus's cache cross-check, which would make the share tier's correctness depend on one test in
+// one module. That is the wrong home for that fact and it is not where it lives.
+//
+// THE SERVE IS THE TIER'S OWN GUARANTEE. `v2.workflow.floor_pure_producer_share` keys every entry on
+// FN-NODE IDENTITY plus a content hash of the full argument row and serves only after the stored
+// argument row verifies structurally equal in portable form, a hash collision degrading to
+// recompute rather than to a wrong value. For a NULLARY producer the argument row is empty, so a
+// wrong serve would mean one declaration's value returned under another declaration's node
+// identity. That invariant is the tier's, it carries the tier's own evidence, and re-asserting it
+// here would be a second authority for it.
+//
+// SO THE WITNESS BELOW GUARDS A DIFFERENT HAZARD, AND THE TWO WERE CONFLATED. Its subject is
+// AUTHORING: whether `current_compile_phase_frontier_standing` names the series its name claims.
+// That is decidable without the cache and is not a statement about serving at all. Its removal is
+// an ordinary loss of a discriminating red -- which is a real loss -- and not a silent conversion of
+// a verified share into an unverified one.
 test fn current_persisted_compile_phase_frontier_holds() -> Bool {
-  match phase_board_series_ratchet(series: self_host_compile_phase_frontier_receipts) {
-    PhaseBoardSeriesHeld => true
-    verdict => false
+  match current_compile_phase_frontier_standing() {
+    CompilePhaseFrontierValidated { latest: _ } => true
+    standing => false
   }
 }
 
@@ -413,7 +444,7 @@ test fn the_persisted_genesis_census_is_fully_attributed_to_its_phases() -> Bool
 // the document renders may not say the emitted compiler clears typeck or borrowck while the latest
 // validated receipt's census says otherwise.
 test fn the_published_frontier_standing_does_not_claim_typeck_or_borrowck_passed() -> Bool {
-  match compile_phase_frontier_standing(series: self_host_compile_phase_frontier_receipts) {
+  match current_compile_phase_frontier_standing() {
     CompilePhaseFrontierValidated { latest: latest } => {
       let rendered = render_phase_board(board: latest.board)
       !string_contains(s: rendered, pattern: "typeck PASSES")
@@ -787,3 +818,23 @@ test fn an_empty_series_refuses_coverage_rather_than_reporting_none_needed() ->
     _ => false
   }
 }
+
+// THE CONSOLIDATED ACCESSOR NAMES THE SAME SUBJECT AS THE SPELLING IT REPLACED.
+//
+// gunbc.self_host_compile_phase_frontier current_compile_phase_frontier_standing exists so that
+// "the standing of THE persisted series" has one home instead of being re-spelled at five call
+// sites. That consolidation has exactly one way to go wrong and it goes wrong SILENTLY: the
+// accessor binds a DIFFERENT series -- a truncated one, a fixture one, a second data declaration
+// added later -- and every consumer keeps compiling and keeps answering, about the wrong subject.
+// No existing claim in either consuming closure would notice, because they all read the accessor
+// and would agree with each other about the wrong thing.
+//
+// So this asserts the identity the rewire assumed, against the general function it delegates to,
+// applied to the series by name. It is not a restatement of the delegation: it is authored one
+// layer above it and it is the only executing place the two spellings are compared. Rebind the
+// accessor to `self_host_compile_phase_frontier_receipts |> skip(n: 1)` -- the perturbation this
+// module's sibling live-gate witnesses already use -- and this reds while nothing else does.
+test fn the_persisted_standing_accessor_agrees_with_the_general_fold_on_the_named_series() -> Bool {
+  current_compile_phase_frontier_standing()
+    == compile_phase_frontier_standing(series: self_host_compile_phase_frontier_receipts)
+}

dag/test/claim/self_host_compile_phase_live_gate_witness_test.dag

@@ -10,6 +10,7 @@ import gunbc.self_host_compile_phase_frontier {
   CompilePhaseFrontierStanding,
   CompilePhaseFrontierValidated,
   compile_phase_frontier_standing,
+  current_compile_phase_frontier_standing,
   self_host_compile_phase_frontier_receipts,
   ParseReached,
   CompilePhaseInvocation
@@ -47,7 +48,7 @@ import gunbc.self_host_compile_phase_live_gate {
 data live_tree_disposition: LiveTreeDisposition = SubstrateInputsOnly
 
 fn latest_receipt() -> CompilePhaseFrontierReceipt? {
-  match compile_phase_frontier_standing(series: self_host_compile_phase_frontier_receipts) {
+  match current_compile_phase_frontier_standing() {
     CompilePhaseFrontierValidated { latest: latest } => Present { value: latest }
     standing => none
   }
@@ -81,7 +82,7 @@ test fn a_live_census_equal_to_the_latest_receipt_holds() -> Bool {
     Absent => false
     Present { value: latest } =>
       match live_tree_frontier_verdict(
-        series: self_host_compile_phase_frontier_receipts,
+        standing: current_compile_phase_frontier_standing(),
         observation: observation_of(receipt: latest, identities: latest.raw_error_diagnostic_identities)
       ) {
         LiveFrontierHeld { live_identity_count: n } => n == count(latest.raw_error_diagnostic_identities)
@@ -101,7 +102,7 @@ test fn a_live_tree_that_gained_an_identity_refuses_and_names_it() -> Bool {
     Absent => false
     Present { value: latest } =>
       match live_tree_frontier_verdict(
-        series: self_host_compile_phase_frontier_receipts,
+        standing: current_compile_phase_frontier_standing(),
         observation: observation_of(
           receipt: latest,
           identities: concat(latest.raw_error_diagnostic_identities, [planted_live_regression_identity])
@@ -122,7 +123,7 @@ test fn a_live_tree_that_swapped_an_identity_at_equal_cardinality_refuses() -> B
     Absent => false
     Present { value: latest } =>
       match live_tree_frontier_verdict(
-        series: self_host_compile_phase_frontier_receipts,
+        standing: current_compile_phase_frontier_standing(),
         observation: observation_of(
           receipt: latest,
           identities: concat(
@@ -146,7 +147,7 @@ test fn a_live_tree_that_removed_an_identity_holds() -> Bool {
     Absent => false
     Present { value: latest } =>
       match live_tree_frontier_verdict(
-        series: self_host_compile_phase_frontier_receipts,
+        standing: current_compile_phase_frontier_standing(),
         observation: observation_of(
           receipt: latest,
           identities: latest.raw_error_diagnostic_identities |> skip(n: 1)
@@ -181,7 +182,7 @@ test fn a_live_observation_from_another_host_target_is_unmeasured_not_held() ->
           classification_policy_digest: latest.subject.classification_policy_digest
         }
       }
-      match live_tree_frontier_verdict(series: self_host_compile_phase_frontier_receipts, observation: foreign) {
+      match live_tree_frontier_verdict(standing: current_compile_phase_frontier_standing(), observation: foreign) {
         LiveFrontierUnmeasured { reason: why } => string_contains(s: why as String, pattern: "host target")
         verdict => false
       }
@@ -245,7 +246,7 @@ test fn an_empty_receipt_series_leaves_the_live_tree_unmeasured_rather_than_held
     Absent => false
     Present { value: latest } =>
       match live_tree_frontier_verdict(
-        series: [],
+        standing: compile_phase_frontier_standing(series: []),
         observation: observation_of(receipt: latest, identities: latest.raw_error_diagnostic_identities)
       ) {
         LiveFrontierUnmeasured { reason: why } => string_contains(s: why as String, pattern: "empty")
@@ -263,7 +264,7 @@ test fn a_non_validating_receipt_series_refuses_the_live_tree() -> Bool {
     Absent => false
     Present { value: latest } =>
       match live_tree_frontier_verdict(
-        series: self_host_compile_phase_frontier_receipts |> skip(n: 1),
+        standing: compile_phase_frontier_standing(series: self_host_compile_phase_frontier_receipts |> skip(n: 1)),
         observation: observation_of(receipt: latest, identities: latest.raw_error_diagnostic_identities)
       ) {
         LiveFrontierRefused { identities: _, reason: why } =>
@@ -323,7 +324,7 @@ test fn a_measurement_that_never_reached_cargo_is_unmeasured_and_never_held() ->
     Absent => false
     Present { value: latest } =>
       match live_tree_verdict_for_measurement(
-        series: self_host_compile_phase_frontier_receipts,
+        standing: current_compile_phase_frontier_standing(),
         m: unreached_measurement,
         toolchain: toolchain_of(receipt: latest)
       ) {
@@ -361,7 +362,7 @@ test fn an_empty_census_from_a_completed_measurement_still_holds() -> Bool {
     Absent => false
     Present { value: latest } =>
       match live_tree_frontier_verdict(
-        series: self_host_compile_phase_frontier_receipts,
+        standing: current_compile_phase_frontier_standing(),
         observation: observation_of(receipt: latest, identities: [])
       ) {
         LiveFrontierHeld { live_identity_count: n } => n == 0