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Complexitylib.Models.RandomAccessMachine.Simulation.RegisterStore.Machine.EntryMatch

RAM sparse-entry matching #

This module exposes the exact framed semantics of the concrete decode-and-match unit used by a bounded sparse register-store scan.

theorem Complexity.RAM.RegisterStore.Machine.entryMatchTM_reachesIn_frame {n : } (tapes : EntryMatchTapes n) (entry : Entry) (rest queryBits : List Bool) (inp₀ : Tape) (work₀ : Fin nTape) (out₀ : Tape) (hsource : (work₀ tapes.source).HasBinarySuffix (entry.encode ++ rest)) (haddress : (work₀ tapes.address).HasBinaryPrefix []) (hvalue : (work₀ tapes.value).HasBinaryPrefix []) (haddressStart : (work₀ tapes.address).cells 0 = Γ.start) (hvalueStart : (work₀ tapes.value).cells 0 = Γ.start) (haddressCounter : (work₀ tapes.addressCounter).HasBinaryNat 0) (haddressWidth : (work₀ tapes.addressWidth).HasBinaryNat 0) (hvalueCounter : (work₀ tapes.valueCounter).HasBinaryNat 0) (hvalueWidth : (work₀ tapes.valueWidth).HasBinaryNat 0) (hquery : (work₀ tapes.query).HasBinaryString queryBits) (hqueryStart : (work₀ tapes.query).cells 0 = Γ.start) (hresult : (work₀ tapes.result).HasBinaryPrefix []) (hresultStart : (work₀ tapes.result).cells 0 = Γ.start) (hinput : TM.Parked inp₀) (hwork : ∀ (i : Fin n), TM.Parked (work₀ i)) (houtput : TM.Parked out₀) :
∃ (c' : Complexity.Cfg n (entryMatchTM tapes).Q), tentryMatchTime entry queryBits, (entryMatchTM tapes).reachesIn t { state := (entryMatchTM tapes).qstart, input := inp₀, work := work₀, output := out₀ } c' (entryMatchTM tapes).halted c' c'.input = inp₀ (c'.work tapes.source).HasBinarySuffix rest (c'.work tapes.address).HasBinaryContent entry.1.bits 1 (c'.work tapes.address).head (c'.work tapes.address).cells 0 = Γ.start (c'.work tapes.value).HasBinaryPrefix entry.2.bits (c'.work tapes.value).cells 0 = Γ.start (c'.work tapes.addressCounter).HasBinaryPrefix (List.replicate (bitlen entry.1) true) (c'.work tapes.addressCounter).cells 0 = Γ.start (c'.work tapes.addressWidth).HasBinaryNat 0 (c'.work tapes.valueCounter).HasBinaryPrefix (List.replicate (bitlen entry.2) true) (c'.work tapes.valueCounter).cells 0 = Γ.start (c'.work tapes.valueWidth).HasBinaryNat 0 (c'.work tapes.query).HasBinaryContent queryBits 1 (c'.work tapes.query).head (c'.work tapes.query).cells 0 = Γ.start (c'.work tapes.result).HasBinaryPrefix [decide (entry.1.bits = queryBits)] (c'.work tapes.result).cells 0 = Γ.start (∀ (i : Fin n), TM.Parked (c'.work i)) (∀ (i : Fin n), i tapes.sourcei tapes.addressi tapes.valuei tapes.addressCounteri tapes.addressWidthi tapes.valueCounteri tapes.valueWidthi tapes.queryi tapes.resultc'.work i = work₀ i) c'.output = out₀

Decode one canonical sparse entry and compare its address with a preserved canonical query, leaving the next entry under the source head.

theorem Complexity.RAM.RegisterStore.Machine.entryMatchReadTM_reachesIn_frame {n : } (tapes : EntryMatchTapes n) (entry : Entry) (rest queryBits : List Bool) (inp₀ : Tape) (work₀ : Fin nTape) (out₀ : Tape) (hsource : (work₀ tapes.source).HasBinarySuffix (entry.encode ++ rest)) (haddress : (work₀ tapes.address).HasBinaryPrefix []) (hvalue : (work₀ tapes.value).HasBinaryPrefix []) (haddressStart : (work₀ tapes.address).cells 0 = Γ.start) (hvalueStart : (work₀ tapes.value).cells 0 = Γ.start) (haddressCounter : (work₀ tapes.addressCounter).HasBinaryNat 0) (haddressWidth : (work₀ tapes.addressWidth).HasBinaryNat 0) (hvalueCounter : (work₀ tapes.valueCounter).HasBinaryNat 0) (hvalueWidth : (work₀ tapes.valueWidth).HasBinaryNat 0) (hquery : (work₀ tapes.query).HasBinaryString queryBits) (hqueryStart : (work₀ tapes.query).cells 0 = Γ.start) (hresult : (work₀ tapes.result).HasBinaryPrefix []) (hresultStart : (work₀ tapes.result).cells 0 = Γ.start) (hinput : TM.Parked inp₀) (hwork : ∀ (i : Fin n), TM.Parked (work₀ i)) (houtput : TM.Parked out₀) :
∃ (c' : Complexity.Cfg n (entryMatchReadTM tapes).Q), tentryMatchReadTime entry queryBits, (entryMatchReadTM tapes).reachesIn t { state := (entryMatchReadTM tapes).qstart, input := inp₀, work := work₀, output := out₀ } c' (entryMatchReadTM tapes).halted c' c'.input = inp₀ ReadableEntryMatch tapes entry rest queryBits work₀ c'.work c'.output = out₀

Decode and compare one canonical sparse entry, then rewind the one-bit result to cell one so that the enclosing bounded scan can branch on it.

theorem Complexity.RAM.RegisterStore.Machine.ReadableEntryMatch.result_read {n : } {tapes : EntryMatchTapes n} {entry : Entry} {rest queryBits : List Bool} {initialWork finalWork : Fin nTape} (h : ReadableEntryMatch tapes entry rest queryBits initialWork finalWork) :
(finalWork tapes.result).read = Γ.ofBool (decide (entry.1.bits = queryBits))

A readable entry-match endpoint exposes its Boolean answer directly under the result-tape head.

theorem Complexity.RAM.RegisterStore.Machine.ReadableEntryMatch.result_read_eq_one_iff {n : } {tapes : EntryMatchTapes n} {entry : Entry} {rest queryBits : List Bool} {initialWork finalWork : Fin nTape} (h : ReadableEntryMatch tapes entry rest queryBits initialWork finalWork) :
(finalWork tapes.result).read = Γ.one entry.1.bits = queryBits

The result head reads one exactly when the decoded address equals the query.

theorem Complexity.RAM.RegisterStore.Machine.entryMatchReadTime_eq (entry : Entry) (queryBits : List Bool) :
entryMatchReadTime entry queryBits = 4 * entry.1.bits.length + 3 * entry.2.bits.length + max entry.1.bits.length queryBits.length + 18

Exact closed form for the readable unary-marker entry-match runtime.

theorem Complexity.RAM.RegisterStore.Machine.entryMatchReadTime_le_linear (entry : Entry) (queryBits : List Bool) :
entryMatchReadTime entry queryBits 5 * entry.1.bits.length + 3 * entry.2.bits.length + queryBits.length + 18

One readable entry match is linear in the serialized entry and query widths.

theorem Complexity.RAM.RegisterStore.Machine.entryMatchTM_prefix_withinAuxSpace {n : } (tapes : EntryMatchTapes n) (entry : Entry) (queryBits : List Bool) (inputLength initialSpace time : ) (start current : Complexity.Cfg n (entryMatchTM tapes).Q) (hinitial : start.WithinAuxSpace inputLength initialSpace) (hreach : (entryMatchTM tapes).reachesIn time start current) (htime : time entryMatchTime entry queryBits) :
current.WithinAuxSpace inputLength (initialSpace + entryMatchTime entry queryBits)

Coarse all-prefix auxiliary-space envelope for one entry match.

Entry matching preserves one-way output safety.

Readable entry matching preserves one-way output safety.

theorem Complexity.RAM.RegisterStore.Machine.entryMatchReadTM_prefix_withinAuxSpace {n : } (tapes : EntryMatchTapes n) (entry : Entry) (queryBits : List Bool) (inputLength initialSpace time : ) (start current : Complexity.Cfg n (entryMatchReadTM tapes).Q) (hinitial : start.WithinAuxSpace inputLength initialSpace) (hreach : (entryMatchReadTM tapes).reachesIn time start current) (htime : time entryMatchReadTime entry queryBits) :
current.WithinAuxSpace inputLength (initialSpace + entryMatchReadTime entry queryBits)

Coarse all-prefix auxiliary-space envelope for readable entry matching.