(* * Copyright (c) Facebook, Inc. and its affiliates. * * This source code is licensed under the MIT license found in the * LICENSE file in the root directory of this source tree. *) (* Proofs about llvm to llair translation that do involve the semantics *) open HolKernel boolLib bossLib Parse lcsymtacs; open listTheory arithmeticTheory pred_setTheory finite_mapTheory wordsTheory integer_wordTheory; open optionTheory rich_listTheory pathTheory alistTheory pairTheory sumTheory; open settingsTheory miscTheory memory_modelTheory; open llvmTheory llvm_propTheory llvm_ssaTheory llairTheory llair_propTheory llvm_to_llairTheory; open llvm_to_llair_propTheory; new_theory "llvm_to_llair_sem_prop"; set_grammar_ancestry ["llvm", "llair", "llair_prop", "llvm_to_llair", "llvm_ssa", "llvm_to_llair_prop"]; numLib.prefer_num (); Definition translate_trace_def: (translate_trace gmap Tau = Tau) ∧ (translate_trace gmap Error = Error) ∧ (translate_trace gmap (Exit i) = (Exit i)) ∧ (translate_trace gmap (W gv bytes) = W (translate_glob_var gmap gv) bytes) End Inductive v_rel: (∀w. v_rel (FlatV (PtrV w)) (FlatV (IntV (w2i w) llair$pointer_size))) ∧ (∀w. v_rel (FlatV (W1V w)) (FlatV (IntV (w2i w) 1))) ∧ (∀w. v_rel (FlatV (W8V w)) (FlatV (IntV (w2i w) 8))) ∧ (∀w. v_rel (FlatV (W32V w)) (FlatV (IntV (w2i w) 32))) ∧ (∀w. v_rel (FlatV (W64V w)) (FlatV (IntV (w2i w) 64))) ∧ (∀vs1 vs2. list_rel v_rel vs1 vs2 ⇒ v_rel (AggV vs1) (AggV vs2)) End Definition take_to_call_def: (take_to_call [] = []) ∧ (take_to_call (i::is) = if terminator i ∨ is_call i then [i] else i :: take_to_call is) End Inductive pc_rel: (* LLVM side points to a normal instruction *) (∀prog emap ip bp d b idx b' prev_i gmap (*rest*). (* Both are valid pointers to blocks in the same function *) dest_fn ip.f = label_to_fname bp ∧ alookup prog ip.f = Some d ∧ alookup d.blocks ip.b = Some b ∧ ip.i = Offset idx ∧ idx < length b.body ∧ get_block (translate_prog prog) bp b' ∧ (* The LLVM side is at the start of a block, or immediately following a * call, which will also start a new block in llair *) (idx ≠ 0 ⇒ get_instr prog (ip with i := Offset (idx - 1)) (Inl prev_i) ∧ is_call prev_i) ∧ (bp, b')::rest = fst (translate_instrs (translate_label (dest_fn ip.f) ip.b (num_calls (take idx b.body))) gmap emap (get_regs_to_keep d) (take_to_call (drop idx b.body))) ⇒ pc_rel prog gmap emap ip bp) ∧ (* If the LLVM side points to phi instructions, the llair side * should point to a block generated from them *) (∀prog gmap emap ip from_l phis to_l bp. bp = Mov_name (dest_fn ip.f) (option_map dest_label from_l) to_l ∧ get_instr prog ip (Inr (from_l, phis)) ∧ ip.b = Some (Lab to_l) ∧ (* We should have just jumped here from block from_l *) (∃d b. alookup prog ip.f = Some d ∧ alookup d.blocks from_l = Some b ∧ ip.b ∈ set (map Some (instr_to_labs (last b.body)))) (*∧ get_block (translate_prog prog) bp (generate_move_block (dest_fn ip.f) gmap emap phis from_l (Lab to_l)) *) ⇒ pc_rel prog gmap emap ip bp) End (* Define when an LLVM state is related to a llair one. * Parameterised on a map for locals relating LLVM registers to llair * expressions that compute the value in that register. This corresponds to part * of the translation's state. *) Definition emap_invariant_def: emap_invariant prog emap s s' r = ∃v v' e. v_rel v.value v' ∧ flookup s.locals r = Some v ∧ flookup emap r = Some e ∧ eval_exp s' e v' End Definition local_state_rel_def: local_state_rel prog emap s s' ⇔ (* Live LLVM registers are mapped and have a related value in the emap * (after evaluating) *) (∀r. r ∈ live prog s.ip ⇒ emap_invariant prog emap s s' r) End Definition globals_rel_def: globals_rel gmap gl gl' ⇔ BIJ (translate_glob_var gmap) (fdom gl) (fdom gl') ∧ ∀k. k ∈ fdom gl ⇒ nfits (w2n (snd (gl ' k))) llair$pointer_size ∧ w2n (snd (gl ' k)) = gl' ' (translate_glob_var gmap k) End Definition mem_state_rel_def: mem_state_rel prog gmap emap (s:llvm$state) (s':llair$state) ⇔ local_state_rel prog emap s s' ∧ reachable prog s.ip ∧ globals_rel gmap s.globals s'.glob_addrs ∧ heap_ok s.heap ∧ erase_tags s.heap = s'.heap ∧ s.status = s'.status End (* Define when an LLVM state is related to a llair one * Parameterised on a map for locals relating LLVM registers to llair * expressions that compute the value in that register. This corresponds to part * of the translation's state. *) Definition state_rel_def: state_rel prog gmap emap (s:llvm$state) (s':llair$state) ⇔ (s.status = Partial ⇒ pc_rel prog gmap emap s.ip s'.bp) ∧ mem_state_rel prog gmap emap s s' End Theorem mem_state_ignore_bp[simp]: ∀prog gmap emap s s' b. mem_state_rel prog gmap emap s (s' with bp := b) ⇔ mem_state_rel prog gmap emap s s' Proof rw [local_state_rel_def, mem_state_rel_def, emap_invariant_def] >> eq_tac >> rw [] >> first_x_assum drule >> rw [] >> `eval_exp (s' with bp := b) e v' ⇔ eval_exp s' e v'` by (irule eval_exp_ignores >> rw []) >> metis_tac [] QED Triviality lemma: ((s:llair$state) with status := Complete code).locals = s.locals ∧ ((s:llair$state) with status := Complete code).glob_addrs = s.glob_addrs Proof rw [] QED Theorem mem_state_rel_exited: ∀prog gmap emap s s' code. mem_state_rel prog gmap emap s s' ⇒ mem_state_rel prog gmap emap (s with status := Complete code) (s' with status := Complete code) Proof rw [mem_state_rel_def, local_state_rel_def, emap_invariant_def] >> metis_tac [eval_exp_ignores, lemma] QED Theorem mem_state_rel_no_update: ∀prog gmap emap s1 s1' v res_v r i i'. assigns prog s1.ip = {} ∧ mem_state_rel prog gmap emap s1 s1' ∧ i ∈ next_ips prog s1.ip ⇒ mem_state_rel prog gmap emap (s1 with ip := i) s1' Proof rw [mem_state_rel_def, local_state_rel_def, emap_invariant_def] >- ( first_x_assum (qspec_then `r` mp_tac) >> simp [Once live_gen_kill, PULL_EXISTS] >> metis_tac [next_ips_same_func]) >- metis_tac [next_ips_reachable] QED Theorem exp_assigns_sing: ∀inst prog ip r t. get_instr prog ip (Inl inst) ∧ classify_instr inst = Exp r t ⇒ assigns prog ip = {(r,t)} Proof rw [get_instr_cases, EXTENSION, IN_DEF, assigns_cases, PULL_EXISTS] >> Cases_on `el idx b.body` >> fs [classify_instr_def, instr_assigns_def] >> Cases_on `p` >> fs [classify_instr_def, instr_assigns_def] QED Theorem mem_state_rel_update: ∀prog gmap emap s1 s1' regs_to_keep v res_v r e i inst. good_emap s1.ip.f prog regs_to_keep gmap emap ∧ get_instr prog s1.ip (Inl inst) ∧ classify_instr inst = Exp r t ∧ r ∉ regs_to_keep ∧ mem_state_rel prog gmap emap s1 s1' ∧ eval_exp s1' (translate_instr_to_exp gmap emap inst) res_v ∧ v_rel v.value res_v ∧ i ∈ next_ips prog s1.ip ⇒ mem_state_rel prog gmap emap (s1 with <|ip := i; locals := s1.locals |+ (r, v) |>) s1' Proof rw [mem_state_rel_def, local_state_rel_def, emap_invariant_def, good_emap_def] >- ( rw [FLOOKUP_UPDATE] >- ( HINT_EXISTS_TAC >> rw [] >> first_x_assum (qspec_then `s1.ip` mp_tac) >> simp [] >> rw [] >> first_x_assum (qspecl_then [`r`, `t`, `inst`] mp_tac) >> rw []) >> `i.f = s1.ip.f` by metis_tac [next_ips_same_func] >> simp [] >> first_x_assum irule >> simp [Once live_gen_kill, PULL_EXISTS, METIS_PROVE [] ``x ∨ y ⇔ (~y ⇒ x)``] >> drule exp_assigns_sing >> rw [] >> metis_tac [exp_assigns_sing]) >- metis_tac [next_ips_reachable] QED Theorem emap_inv_updates_keep_same_ip1: ∀prog emap ip s s' vs res_vs rtys r t. list_rel v_rel (map (\v. v.value) vs) res_vs ∧ length rtys = length vs ∧ (r,t) ∈ set rtys ∧ all_distinct (map fst rtys) ∧ flookup emap r = Some (Var (translate_reg r t) F) ⇒ emap_invariant prog emap (s with locals := s.locals |++ zip (map fst rtys, vs)) (s' with locals := s'.locals |++ zip (map (\(r,ty). translate_reg r ty) rtys, res_vs)) r Proof rw [emap_invariant_def, flookup_fupdate_list] >> CASE_TAC >> rw [] >- ( fs [ALOOKUP_NONE, MAP_REVERSE] >> rfs [MAP_ZIP] >> fs [MEM_MAP] >> metis_tac [FST]) >> rename [`alookup (reverse (zip _)) _ = Some v`] >> fs [Once MEM_SPLIT_APPEND_last] >> fs [alookup_some, MAP_EQ_APPEND, reverse_eq_append] >> rw [] >> rfs [zip_eq_append] >> rw [] >> rw [] >> fs [] >> rw [] >> qpat_x_assum `reverse _ ++ _ = zip _` (mp_tac o GSYM) >> rw [zip_eq_append] >> fs [] >> rw [] >> rename [`[_] = zip (x,y)`] >> Cases_on `x` >> Cases_on `y` >> fs [] >> rw [] >> fs [LIST_REL_SPLIT1] >> rw [] >> HINT_EXISTS_TAC >> rw [] >> rw [Once eval_exp_cases, flookup_fupdate_list] >> qmatch_goalsub_abbrev_tac `reverse (zip (a, b))` >> `length a = length b` by ( rw [Abbr `a`, Abbr `b`] >> metis_tac [LIST_REL_LENGTH, LENGTH_MAP, LENGTH_ZIP, LENGTH_REVERSE, ADD_COMM, ADD_ASSOC]) >> CASE_TAC >> rw [] >> fs [alookup_some, reverse_eq_append] >- (fs [ALOOKUP_NONE] >> rfs [MAP_REVERSE, MAP_ZIP] >> fs [Abbr `a`]) >> rfs [zip_eq_append] >> unabbrev_all_tac >> rw [] >> qpat_x_assum `reverse _ ++ _ = zip _` (mp_tac o GSYM) >> rw [zip_eq_append] >> fs [] >> rw [] >> rename [`[_] = zip (a,b)`] >> Cases_on `a` >> Cases_on `b` >> fs [] >> rw [] >> fs [] >> rw [] >> fs [ALOOKUP_NONE] >> fs [] >> rev_full_simp_tac pure_ss [SWAP_REVERSE_SYM] >> rw [] >> fs [MAP_REVERSE] >> rfs [MAP_ZIP] >> fs [MIN_DEF] >> BasicProvers.EVERY_CASE_TAC >> fs [] >> rfs [] >> rw [] >> fs [MAP_MAP_o, combinTheory.o_DEF, LAMBDA_PROD] >> rename [`map fst l1 ++ [_] ++ map fst l2 = l3 ++ [_] ++ l4`, `map _ l1 ++ [translate_reg _ _] ++ _ = l5 ++ _ ++ l6`, `l7 ++ [v1:llair$flat_v reg_v] ++ l8 = l9 ++ [v2] ++ l10`] >> `map fst l1 = l3 ∧ map fst l2 = l4` by ( irule append_split_last >> qexists_tac `h` >> rw [MEM_MAP] >> CCONTR_TAC >> fs [] >> `all_distinct (map fst l1 ++ [fst y] ++ map fst l2)` by metis_tac [] >> fs [ALL_DISTINCT_APPEND, MEM_MAP] >> metis_tac [FST, pair_CASES]) >> `length l2 = length l6` suffices_by metis_tac [append_split_eq, LIST_REL_LENGTH, LENGTH_MAP] >> rename1 `translate_reg r t` >> `~mem (translate_reg r t) (map (λ(r,ty). translate_reg r ty) l2)` by ( rw [MEM_MAP] >> pairarg_tac >> fs [] >> rename1 `translate_reg r1 t1 = translate_reg r2 t2` >> Cases_on `r1` >> Cases_on `r2` >> rw [translate_reg_def] >> metis_tac [MEM_MAP, FST]) >> metis_tac [append_split_last, LENGTH_MAP] QED Theorem emap_inv_updates_keep_same_ip2: ∀prog emap s s' vs res_vs rtys r regs_to_keep gmap. is_ssa prog ∧ good_emap s.ip.f prog regs_to_keep gmap emap ∧ r ∈ live prog s.ip ∧ assigns prog s.ip = set rtys ∧ emap_invariant prog emap s s' r ∧ list_rel v_rel (map (\v. v.value) vs) res_vs ∧ length rtys = length vs ∧ reachable prog s.ip ∧ ¬mem r (map fst rtys) ⇒ emap_invariant prog emap (s with locals := s.locals |++ zip (map fst rtys, vs)) (s' with locals := s'.locals |++ zip (map (\(r,ty). translate_reg r ty) rtys, res_vs)) r Proof rw [emap_invariant_def, alistTheory.flookup_fupdate_list] >> rw [] >> CASE_TAC >> rw [] >- ( qexists_tac `v'` >> rw [] >> qmatch_goalsub_abbrev_tac `eval_exp s_upd _ _` >> `DRESTRICT s_upd.locals (exp_uses e) = DRESTRICT s'.locals (exp_uses e) ∧ s_upd.glob_addrs = s'.glob_addrs` suffices_by metis_tac [eval_exp_ignores_unused] >> rw [Abbr `s_upd`] >> qmatch_goalsub_abbrev_tac `_ |++ l = _` >> `l = []` suffices_by rw [FUPDATE_LIST_THM] >> rw [Abbr `l`, FILTER_EQ_NIL, LAMBDA_PROD] >> `(λ(p1,p2:llair$flat_v reg_v). p1 ∉ exp_uses e) = (\x. fst x ∉ exp_uses e)` by (rw [EXTENSION, IN_DEF] >> pairarg_tac >> rw []) >> `length rtys = length res_vs` by metis_tac [LIST_REL_LENGTH, LENGTH_MAP] >> rw [every_zip_fst, EVERY_MAP] >> rw [LAMBDA_PROD] >> rw [EVERY_EL] >> pairarg_tac >> rw [] >> qmatch_goalsub_rename_tac `translate_reg r1 ty1 ∉ exp_uses _` >> fs [good_emap_def] >> first_x_assum (qspec_then `s.ip` mp_tac) >> rw [] >> first_x_assum drule >> simp [] >> disch_then (qspec_then `translate_reg r1 ty1` mp_tac) >> rw [] >> CCONTR_TAC >> fs [] >> `ip_equiv ip2 s.ip` by ( fs [is_ssa_def, EXTENSION, IN_DEF] >> Cases_on `r1` >> fs [translate_reg_def, untranslate_reg_def] >> rename1 `Reg reg = fst regty` >> Cases_on `regty` >> fs [] >> rw [] >> `assigns prog s.ip (Reg reg, ty1)` suffices_by metis_tac [reachable_dominates_same_func, FST] >> metis_tac [EL_MEM, IN_DEF]) >> metis_tac [dominates_irrefl, ip_equiv_dominates2]) >> drule ALOOKUP_MEM >> rw [MEM_MAP, MEM_ZIP] >> metis_tac [EL_MEM, LIST_REL_LENGTH, LENGTH_MAP] QED Theorem local_state_rel_next_ip: ∀prog emap ip2 s s'. local_state_rel prog emap s s' ∧ ip2 ∈ next_ips prog s.ip ∧ (∀r. r ∈ assigns prog s.ip ⇒ emap_invariant prog emap s s' (fst r)) ⇒ local_state_rel prog emap (s with ip := ip2) s' Proof rw [local_state_rel_def, emap_invariant_def] >> Cases_on `r ∈ live prog s.ip` >> fs [] >> pop_assum mp_tac >> simp [Once live_gen_kill, PULL_EXISTS] >> rw [] >> first_x_assum (qspec_then `ip2` mp_tac) >> rw [] >> first_x_assum drule >> rw [] >> ntac 3 HINT_EXISTS_TAC >> rw [] >> first_x_assum irule >> rw [] >> metis_tac [next_ips_same_func] QED Theorem local_state_rel_updates_keep: ∀rtys prog emap s s' vs res_vs i regs_to_keep gmap. is_ssa prog ∧ good_emap s.ip.f prog regs_to_keep gmap emap ∧ all_distinct (map fst rtys) ∧ set rtys = assigns prog s.ip ∧ (¬∃inst r t. get_instr prog s.ip (Inl inst) ∧ classify_instr inst = Exp r t ∧ r ∉ regs_to_keep) ∧ local_state_rel prog emap s s' ∧ length vs = length rtys ∧ list_rel v_rel (map (\v. v.value) vs) res_vs ∧ i ∈ next_ips prog s.ip ∧ reachable prog s.ip ⇒ local_state_rel prog emap (s with <| ip := i; locals := s.locals |++ zip (map fst rtys, vs) |>) (s' with locals := s'.locals |++ zip (map (\(r,ty). translate_reg r ty) rtys, res_vs)) Proof rw [] >> irule local_state_rel_next_ip >> fs [local_state_rel_def] >> rw [] >- ( irule emap_inv_updates_keep_same_ip1 >> rw [] >> fs [good_emap_def] >> first_x_assum (qspec_then `s.ip` mp_tac) >> rw [] >> qexists_tac `snd r` >> rw [] >> first_x_assum irule >> rw [] >> fs [assigns_cases, IN_DEF, not_exp_def] >> metis_tac []) >> Cases_on `mem r (map fst rtys)` >- ( irule emap_inv_updates_keep_same_ip1 >> rw [] >> `∃t. (r,t) ∈ set rtys` by (fs [MEM_MAP] >> metis_tac [FST, pair_CASES]) >> rfs [good_emap_def] >> first_x_assum (qspec_then `s.ip` mp_tac) >> rw [] >> `(∃inst. get_instr prog s.ip (Inl inst)) ∨ (∃phis. get_instr prog s.ip (Inr phis))` by (fs [IN_DEF, assigns_cases] >> metis_tac []) >> metis_tac [FST, PAIR_EQ, SND,not_exp_def]) >- ( irule emap_inv_updates_keep_same_ip2 >> rw [] >> metis_tac []) QED Theorem local_state_rel_update_keep: ∀prog emap s s' v res_v r i ty regs_to_keep gmap. is_ssa prog ∧ good_emap s.ip.f prog regs_to_keep gmap emap ∧ assigns prog s.ip = {(r,ty)} ∧ (¬∃inst r t. get_instr prog s.ip (Inl inst) ∧ classify_instr inst = Exp r t ∧ r ∉ regs_to_keep) ∧ local_state_rel prog emap s s' ∧ v_rel v.value res_v ∧ reachable prog s.ip ∧ i ∈ next_ips prog s.ip ⇒ local_state_rel prog emap (s with <| ip := i; locals := s.locals |+ (r, v) |>) (s' with locals := s'.locals |+ (translate_reg r ty, res_v)) Proof rw [] >> drule local_state_rel_updates_keep >> disch_then (qspecl_then [`[(r,ty)]`, `emap`, `s`, `s'`] mp_tac) >> simp [] >> disch_then drule >> disch_then (qspecl_then [`[v]`, `[res_v]`] mp_tac) >> simp [] >> disch_then drule >> rw [FUPDATE_LIST_THM] QED Theorem mem_state_rel_update_keep: ∀prog gmap emap s s' v res_v r ty i inst regs_to_keep. is_ssa prog ∧ good_emap s.ip.f prog regs_to_keep gmap emap ∧ assigns prog s.ip = {(r,ty)} ∧ (¬∃inst r t. get_instr prog s.ip (Inl inst) ∧ classify_instr inst = Exp r t ∧ r ∉ regs_to_keep) ∧ mem_state_rel prog gmap emap s s' ∧ v_rel v.value res_v ∧ reachable prog s.ip ∧ i ∈ next_ips prog s.ip ⇒ mem_state_rel prog gmap emap (s with <| ip := i; locals := s.locals |+ (r, v) |>) (s' with locals := s'.locals |+ (translate_reg r ty, res_v)) Proof rw [mem_state_rel_def] >- ( irule local_state_rel_update_keep >> rw [] >> metis_tac [get_instr_func, INL_11, instr_class_11, instr_class_distinct, classify_instr_def]) >- metis_tac [next_ips_reachable] QED Triviality lemma: ((s:llair$state) with heap := h).locals = s.locals ∧ ((s:llair$state) with heap := h).glob_addrs = s.glob_addrs Proof rw [] QED Theorem mem_state_rel_heap_update: ∀prog gmap emap s s' h h'. mem_state_rel prog gmap emap s s' ∧ heap_ok h ∧ erase_tags h = erase_tags h' ⇒ mem_state_rel prog gmap emap (s with heap := h) (s' with heap := h') Proof rw [mem_state_rel_def, erase_tags_def, local_state_rel_def] >> rw [heap_component_equality] >> fs [fmap_eq_flookup, FLOOKUP_o_f] >> rw [] >> first_x_assum (qspec_then `x` mp_tac) >> BasicProvers.EVERY_CASE_TAC >> rw [] >> fs [emap_invariant_def] >- metis_tac [eval_exp_ignores, lemma] >- metis_tac [eval_exp_ignores, lemma] >> Cases_on `x'` >> Cases_on `x''` >> fs [] QED Theorem v_rel_bytes: ∀v v'. v_rel v v' ⇒ llvm_value_to_bytes v = llair_value_to_bytes v' Proof ho_match_mp_tac v_rel_ind >> rw [v_rel_cases, llvm_value_to_bytes_def, llair_value_to_bytes_def] >> rw [value_to_bytes_def, llvmTheory.unconvert_value_def, w2n_i2n, llairTheory.unconvert_value_def, llairTheory.pointer_size_def, llvmTheory.pointer_size_def] >> pop_assum mp_tac >> qid_spec_tac `vs1` >> Induct_on `vs2` >> rw [] >> rw [] QED Theorem bytes_v_rel_lem: (∀f s bs t. f = (λn t w. convert_value t w) ∧ s = type_to_shape t ∧ first_class_type t ⇒ (quotient_pair$### v_rel $=) (bytes_to_value f s bs) (bytes_to_value (λn t w. convert_value t w) (type_to_shape (translate_ty t)) bs)) ∧ (∀f n s bs t. f = (λn t w. convert_value t w) ∧ s = type_to_shape t ∧ first_class_type t ⇒ (quotient_pair$### (list_rel v_rel) $=) (read_array f n s bs) (read_array (λn t w. convert_value t w) n (type_to_shape (translate_ty t)) bs)) ∧ (∀f ss bs ts. f = (λn t w. convert_value t w) ∧ ss = map type_to_shape ts ∧ every first_class_type ts ⇒ (quotient_pair$### (list_rel v_rel) $=) (read_str f ss bs) (read_str (λn t w. convert_value t w) (map (type_to_shape o translate_ty) ts) bs)) Proof ho_match_mp_tac bytes_to_value_ind >> rw [llvmTheory.type_to_shape_def, translate_ty_def, type_to_shape_def, sizeof_def, llvmTheory.sizeof_def, bytes_to_value_def, pointer_size_def, convert_value_def, llvmTheory.convert_value_def, quotient_pairTheory.PAIR_REL] >- ( Cases_on `t'` >> fs [llvmTheory.type_to_shape_def, llvmTheory.sizeof_def, llvmTheory.first_class_type_def] >> TRY (Cases_on `s`) >> rw [llvmTheory.sizeof_def, le_read_num_def, translate_size_def, convert_value_def, llvmTheory.convert_value_def, translate_ty_def, type_to_shape_def, bytes_to_value_def, sizeof_def, llvmTheory.sizeof_def] >> simp [v_rel_cases] >> rw [word_0_w2i, w2i_1] >> fs [pointer_size_def, llvmTheory.pointer_size_def] >> qmatch_goalsub_abbrev_tac `l2n 256 l` >> qmatch_goalsub_abbrev_tac `n2i n dim` >> `n < 2 ** dim` by ( qspecl_then [`l`, `256`] mp_tac numposrepTheory.l2n_lt >> rw [] >> `256 ** length l ≤ 2 ** dim` suffices_by decide_tac >> `256 = 2 ** 8` by rw [] >> full_simp_tac bool_ss [] >> REWRITE_TAC [GSYM EXP_EXP_MULT] >> rw [EXP_BASE_LE_MONO] >> unabbrev_all_tac >> rw []) >> metis_tac [w2i_n2w, dimword_def, dimindex_8, dimindex_32, dimindex_64]) >- ( Cases_on `t` >> fs [llvmTheory.type_to_shape_def, llvmTheory.sizeof_def, llvmTheory.first_class_type_def] >> rw [PAIR_MAP] >> pairarg_tac >> fs [type_to_shape_def, translate_ty_def, bytes_to_value_def] >> first_x_assum (qspec_then `t'` mp_tac) >> simp [] >> simp [v_rel_cases] >> pairarg_tac >> fs [] >> pairarg_tac >> fs [] >> rw []) >- ( Cases_on `t` >> fs [llvmTheory.type_to_shape_def, llvmTheory.sizeof_def, llvmTheory.first_class_type_def] >> rw [PAIR_MAP] >> fs [type_to_shape_def, translate_ty_def, bytes_to_value_def] >> pairarg_tac >> fs [PAIR_MAP] >> first_x_assum (qspec_then `l` mp_tac) >> simp [] >> simp [v_rel_cases] >> pairarg_tac >> fs [] >> pairarg_tac >> fs [MAP_MAP_o] >> rw [] >> fs [ETA_THM]) >- ( rpt (pairarg_tac >> fs []) >> first_x_assum (qspec_then `t` mp_tac) >> rw [] >> first_x_assum (qspec_then `t` mp_tac) >> rw []) >- ( Cases_on `ts` >> fs [bytes_to_value_def] >> rpt (pairarg_tac >> fs []) >> first_x_assum (qspec_then `h` mp_tac) >> simp [] >> strip_tac >> fs [] >> rfs [] >> fs [] >> first_x_assum (qspec_then `t` mp_tac) >> simp [] >> strip_tac >> fs [MAP_MAP_o] >> rw []) QED Theorem bytes_v_rel: ∀t bs. first_class_type t ⇒ v_rel (fst (bytes_to_llvm_value t bs)) (fst (bytes_to_llair_value (translate_ty t) bs)) Proof rw [bytes_to_llvm_value_def, bytes_to_llair_value_def] >> qspecl_then [`bs`, `t`] mp_tac (CONJUNCT1 (SIMP_RULE (srw_ss()) [] bytes_v_rel_lem)) >> rw [quotient_pairTheory.PAIR_REL] >> pairarg_tac >> fs [] >> pairarg_tac >> fs [] QED Triviality n2i_lem: ∀n. nfits n llair$pointer_size ⇒ n2i n llair$pointer_size = IntV (w2i (n2w n : word64)) llair$pointer_size Proof rw [pointer_size_def] >> `2 ** 64 = dimword (:64)` by rw [dimword_64] >> full_simp_tac bool_ss [nfits_def] >> drule w2i_n2w >> rw [] QED Theorem translate_constant_correct_lem: (∀c s prog gmap emap s' v. mem_state_rel prog gmap emap s s' ∧ eval_const s.globals c v ⇒ ∃v'. eval_exp s' (translate_const gmap c) v' ∧ v_rel v v') ∧ (∀(cs : (ty # const) list) s prog gmap emap s' vs. mem_state_rel prog gmap emap s s' ∧ list_rel (eval_const s.globals o snd) cs vs ⇒ ∃v'. list_rel (eval_exp s') (map (translate_const gmap o snd) cs) v' ∧ list_rel v_rel vs v') ∧ (∀(tc : ty # const) s prog gmap emap s' v. mem_state_rel prog gmap emap s s' ∧ eval_const s.globals (snd tc) v ⇒ ∃v'. eval_exp s' (translate_const gmap (snd tc)) v' ∧ v_rel v v') Proof ho_match_mp_tac const_induction >> rw [translate_const_def] >> pop_assum mp_tac >> simp [Once eval_const_cases] >- ( rw [Once eval_exp_cases] >> simp [Once eval_const_cases, translate_size_def, v_rel_cases] >> metis_tac [truncate_2comp_i2w_w2i, dimindex_1, dimindex_8, dimindex_32, dimindex_64]) >- ( rw [Once eval_exp_cases] >> simp [v_rel_cases, PULL_EXISTS, MAP_MAP_o] >> fs [combinTheory.o_DEF, LAMBDA_PROD] >> rw [] >> first_x_assum drule >> disch_then irule >> fs [LIST_REL_EL_EQN] >> rw [] >> rfs [] >> first_x_assum drule >> simp [EL_MAP] >> Cases_on `el n cs` >> simp []) >- ( rw [Once eval_exp_cases] >> simp [v_rel_cases, PULL_EXISTS, MAP_MAP_o] >> fs [combinTheory.o_DEF, LAMBDA_PROD] >> rw [] >> first_x_assum drule >> disch_then irule >> fs [LIST_REL_EL_EQN] >> rw [] >> rfs [] >> first_x_assum drule >> simp [EL_MAP] >> Cases_on `el n cs` >> simp []) (* TODO: unimplemented GEP stuff *) >- cheat >- ( rw [Once eval_exp_cases] >> simp [v_rel_cases] >> fs [mem_state_rel_def, globals_rel_def] >> first_x_assum (qspec_then `g` mp_tac) >> rw [] >> qexists_tac `w2n w` >> rw [] >> fs [FLOOKUP_DEF] >- ( rfs [] >> qpat_x_assum `w2n _ = _` (mp_tac o GSYM) >> rw [] >> simp [n2i_lem]) >- rfs [BIJ_DEF, INJ_DEF, SURJ_DEF]) >- metis_tac [] QED Theorem translate_constant_correct: ∀c s prog gmap emap s' g v. mem_state_rel prog gmap emap s s' ∧ eval_const s.globals c v ⇒ ∃v'. eval_exp s' (translate_const gmap c) v' ∧ v_rel v v' Proof metis_tac [translate_constant_correct_lem] QED Theorem translate_const_no_reg[simp]: ∀gmap c. r ∉ exp_uses (translate_const gmap c) Proof ho_match_mp_tac translate_const_ind >> rw [translate_const_def, exp_uses_def, MEM_MAP, METIS_PROVE [] ``x ∨ y ⇔ (~x ⇒ y)``] >- (pairarg_tac >> fs [] >> metis_tac []) >- (pairarg_tac >> fs [] >> metis_tac []) (* TODO: unimplemented GEP stuff *) >- cheat QED Theorem translate_arg_correct: ∀s a v prog gmap emap s'. mem_state_rel prog gmap emap s s' ∧ eval s a v ∧ arg_to_regs a ⊆ live prog s.ip ⇒ ∃v'. eval_exp s' (translate_arg gmap emap a) v' ∧ v_rel v.value v' Proof Cases_on `a` >> rw [eval_cases, translate_arg_def] >> rw [] >- metis_tac [translate_constant_correct] >> CASE_TAC >> fs [PULL_EXISTS, mem_state_rel_def, local_state_rel_def, emap_invariant_def, arg_to_regs_def] >> res_tac >> rfs [] >> metis_tac [eval_exp_ignores] QED Theorem is_allocated_mem_state_rel: ∀prog gmap emap s1 s1'. mem_state_rel prog gmap emap s1 s1' ⇒ (∀i. is_allocated i s1.heap ⇔ is_allocated i s1'.heap) Proof rw [mem_state_rel_def, is_allocated_def, erase_tags_def] >> pop_assum mp_tac >> pop_assum (mp_tac o GSYM) >> rw [] QED Theorem restricted_i2w_11: ∀i (w:'a word). INT_MIN (:'a) ≤ i ∧ i ≤ INT_MAX (:'a) ⇒ (i2w i : 'a word) = i2w (w2i w) ⇒ i = w2i w Proof rw [i2w_def] >- ( Cases_on `n2w (Num (-i)) = INT_MINw` >> rw [w2i_neg, w2i_INT_MINw] >> fs [word_L_def] >> `∃j. 0 ≤ j ∧ i = -j` by intLib.COOPER_TAC >> rw [] >> fs [] >> `INT_MIN (:'a) < dimword (:'a)` by metis_tac [INT_MIN_LT_DIMWORD] >> `Num j MOD dimword (:'a) = Num j` by (irule LESS_MOD >> intLib.COOPER_TAC) >> fs [] >- intLib.COOPER_TAC >- ( `Num j < INT_MIN (:'a)` by intLib.COOPER_TAC >> fs [w2i_n2w_pos, integerTheory.INT_OF_NUM])) >- ( fs [GSYM INT_MAX, INT_MAX_def] >> `Num i < INT_MIN (:'a)` by intLib.COOPER_TAC >> rw [w2i_n2w_pos, integerTheory.INT_OF_NUM] >> intLib.COOPER_TAC) QED Theorem translate_sub_correct: ∀prog gmap emap s1 s1' nsw nuw ty v1 v1' v2 v2' e2' e1' result. do_sub nuw nsw v1 v2 ty = Some result ∧ eval_exp s1' e1' v1' ∧ v_rel v1.value v1' ∧ eval_exp s1' e2' v2' ∧ v_rel v2.value v2' ⇒ ∃v3'. eval_exp s1' (Sub (translate_ty ty) e1' e2') v3' ∧ v_rel result.value v3' Proof rw [] >> simp [Once eval_exp_cases] >> fs [do_sub_def] >> rw [] >> rfs [v_rel_cases] >> rw [] >> fs [] >> BasicProvers.EVERY_CASE_TAC >> fs [PULL_EXISTS, translate_ty_def, translate_size_def] >> pairarg_tac >> fs [] >> fs [PAIR_MAP, wordsTheory.FST_ADD_WITH_CARRY] >> rw [] >> qmatch_goalsub_abbrev_tac `w2i (-1w * w1 + w2)` >> qexists_tac `w2i w2` >> qexists_tac `w2i w1` >> simp [] >> unabbrev_all_tac >> rw [] >- ( irule restricted_i2w_11 >> simp [word_sub_i2w] >> `dimindex (:1) = 1` by rw [] >> drule truncate_2comp_i2w_w2i >> rw [word_sub_i2w] >> metis_tac [w2i_ge, w2i_le, SIMP_CONV (srw_ss()) [] ``INT_MIN (:1)``, SIMP_CONV (srw_ss()) [] ``INT_MAX (:1)``]) >- ( irule restricted_i2w_11 >> simp [word_sub_i2w] >> `dimindex (:8) = 8` by rw [] >> drule truncate_2comp_i2w_w2i >> rw [word_sub_i2w] >> metis_tac [w2i_ge, w2i_le, SIMP_CONV (srw_ss()) [] ``INT_MIN (:8)``, SIMP_CONV (srw_ss()) [] ``INT_MAX (:8)``]) >- ( irule restricted_i2w_11 >> simp [word_sub_i2w] >> `dimindex (:32) = 32` by rw [] >> drule truncate_2comp_i2w_w2i >> rw [word_sub_i2w] >> metis_tac [w2i_ge, w2i_le, SIMP_CONV (srw_ss()) [] ``INT_MIN (:32)``, SIMP_CONV (srw_ss()) [] ``INT_MAX (:32)``]) >- ( irule restricted_i2w_11 >> simp [word_sub_i2w] >> `dimindex (:64) = 64` by rw [] >> drule truncate_2comp_i2w_w2i >> rw [word_sub_i2w] >> metis_tac [w2i_ge, w2i_le, SIMP_CONV (srw_ss()) [] ``INT_MIN (:64)``, SIMP_CONV (srw_ss()) [] ``INT_MAX (:64)``]) QED Theorem translate_extract_correct: ∀prog gmap emap s1 s1' a v v1' e1' cs vs ns result. mem_state_rel prog gmap emap s1 s1' ∧ list_rel (eval_const s1.globals) cs vs ∧ map signed_v_to_num vs = map Some ns ∧ extract_value v ns = Some result ∧ eval_exp s1' e1' v1' ∧ v_rel v v1' ⇒ ∃v2'. eval_exp s1' (foldl (λe c. Select e (translate_const gmap c)) e1' cs) v2' ∧ v_rel result v2' Proof Induct_on `cs` >> rw [] >> rfs [] >> fs [extract_value_def] >- metis_tac [] >> first_x_assum irule >> Cases_on `ns` >> fs [] >> qmatch_goalsub_rename_tac `translate_const gmap c` >> qmatch_assum_rename_tac `eval_const _ _ v3` >> `∃v2'. eval_exp s1' (translate_const gmap c) v2' ∧ v_rel v3 v2'` by metis_tac [translate_constant_correct] >> Cases_on `v` >> fs [extract_value_def] >> qpat_x_assum `v_rel (AggV _) _` mp_tac >> simp [Once v_rel_cases] >> rw [] >> simp [Once eval_exp_cases, PULL_EXISTS] >> fs [LIST_REL_EL_EQN] >> qmatch_assum_rename_tac `_ = map Some is` >> Cases_on `v3` >> fs [signed_v_to_num_def, signed_v_to_int_def] >> rw [] >> `∃i. v2' = FlatV i` by fs [v_rel_cases] >> fs [] >> qmatch_assum_rename_tac `option_join _ = Some x` >> `∃size. i = IntV (&x) size` suffices_by metis_tac [] >> rw [] >> qpat_x_assum `v_rel _ _` mp_tac >> simp [v_rel_cases] >> rw [] >> fs [signed_v_to_int_def] >> rw [] >> intLib.COOPER_TAC QED Theorem translate_update_correct: ∀prog gmap emap s1 s1' a v1 v1' v2 v2' e2 e2' e1' cs vs ns result. mem_state_rel prog gmap emap s1 s1' ∧ list_rel (eval_const s1.globals) cs vs ∧ map signed_v_to_num vs = map Some ns ∧ insert_value v1 v2 ns = Some result ∧ eval_exp s1' e1' v1' ∧ v_rel v1 v1' ∧ eval_exp s1' e2' v2' ∧ v_rel v2 v2' ⇒ ∃v3'. eval_exp s1' (translate_updatevalue gmap e1' e2' cs) v3' ∧ v_rel result v3' Proof Induct_on `cs` >> rw [] >> rfs [] >> fs [insert_value_def, translate_updatevalue_def] >- metis_tac [] >> simp [Once eval_exp_cases, PULL_EXISTS] >> Cases_on `ns` >> fs [] >> Cases_on `v1` >> fs [insert_value_def] >> rename [`insert_value (el x _) _ ns`] >> Cases_on `insert_value (el x l) v2 ns` >> fs [] >> rw [] >> qpat_x_assum `v_rel (AggV _) _` mp_tac >> simp [Once v_rel_cases] >> rw [] >> simp [v_rel_cases] >> qmatch_goalsub_rename_tac `translate_const gmap c` >> qexists_tac `vs2` >> simp [] >> qmatch_assum_rename_tac `eval_const _ _ v3` >> `∃v4'. eval_exp s1' (translate_const gmap c) v4' ∧ v_rel v3 v4'` by metis_tac [translate_constant_correct] >> `∃idx_size. v4' = FlatV (IntV (&x) idx_size)` by ( pop_assum mp_tac >> simp [Once v_rel_cases] >> rw [] >> fs [signed_v_to_num_def, signed_v_to_int_def] >> intLib.COOPER_TAC) >> first_x_assum drule >> disch_then drule >> disch_then drule >> disch_then drule >> disch_then (qspecl_then [`el x vs2`, `v2'`, `e2'`, `Select e1' (translate_const gmap c)`] mp_tac) >> simp [Once eval_exp_cases] >> metis_tac [EVERY2_LUPDATE_same, LIST_REL_LENGTH, LIST_REL_EL_EQN] QED val sizes = [``:1``, ``:8``, ``:32``, ``:64``]; val trunc_thms = LIST_CONJ (map (fn x => SIMP_RULE (srw_ss()) [] (INST_TYPE [``:'a`` |-> x] truncate_2comp_i2w_w2i)) sizes); val signed2unsigned_thms = LIST_CONJ (map (fn x => SIMP_RULE (srw_ss()) [] (INST_TYPE [``:'a`` |-> x] (GSYM w2n_signed2unsigned))) sizes); Definition good_cast_def: (good_cast Trunc (FlatV (IntV i size)) from_bits to_t ⇔ from_bits = size ∧ llair$sizeof_bits to_t < from_bits) ∧ (good_cast Zext (FlatV (IntV i size)) from_bits to_t ⇔ from_bits = size ∧ from_bits < sizeof_bits to_t) ∧ (good_cast Sext (FlatV (IntV i size)) from_bits to_t ⇔ from_bits = size ∧ from_bits < sizeof_bits to_t) ∧ (good_cast Ptrtoint _ _ _ ⇔ T) ∧ (good_cast Inttoptr _ _ _ ⇔ T) End Theorem translate_cast_correct: ∀prog gmap emap s1' cop from_bits to_ty v1 v1' e1' result. do_cast cop v1.value to_ty = Some result ∧ eval_exp s1' e1' v1' ∧ v_rel v1.value v1' ∧ good_cast cop v1' from_bits (translate_ty to_ty) ⇒ ∃v3'. eval_exp s1' ((if (cop = Zext) then Unsigned else Signed) (if cop = Trunc then sizeof_bits (translate_ty to_ty) else from_bits) e1' (translate_ty to_ty)) v3' ∧ v_rel result v3' Proof rw [] >> simp [Once eval_exp_cases, PULL_EXISTS, Once v_rel_cases] >- ( (* Zext *) fs [do_cast_def, OPTION_JOIN_EQ_SOME, unsigned_v_to_num_some, w64_cast_some, translate_ty_def, sizeof_bits_def, translate_size_def] >> rw [] >> rfs [v_rel_cases] >> rw [] >> qmatch_assum_abbrev_tac `eval_exp _ _ (FlatV (IntV i s))` >> qexists_tac `i` >> qexists_tac `s` >> rw [] >> unabbrev_all_tac >> fs [good_cast_def, translate_ty_def, sizeof_bits_def, translate_size_def] >> rw [trunc_thms, signed2unsigned_thms] >> rw [GSYM w2w_def, w2w_w2w, WORD_ALL_BITS] >> rw [w2i_w2w_expand]) >- ( (* Trunc *) fs [do_cast_def] >> rw [] >> fs [OPTION_JOIN_EQ_SOME, w64_cast_some, unsigned_v_to_num_some, signed_v_to_int_some, mk_ptr_some] >> rw [sizeof_bits_def, translate_ty_def, translate_size_def] >> rfs [] >> fs [v_rel_cases] >> rw [] >> qmatch_assum_abbrev_tac `eval_exp _ _ (FlatV (IntV i s))` >> qexists_tac `s` >> qexists_tac `i` >> rw [] >> unabbrev_all_tac >> fs [good_cast_def, translate_ty_def, sizeof_bits_def, translate_size_def] >> rw [w2w_n2w, GSYM w2w_def, trunc_thms, pointer_size_def] >> rw [i2w_w2i_extend, WORD_w2w_OVER_MUL] >> rw [w2w_w2w, WORD_ALL_BITS, word_bits_w2w] >> rw [word_mul_def]) >> Cases_on `cop` >> fs [] >> rw [] >- ( (* Sext *) fs [do_cast_def] >> rw [] >> fs [OPTION_JOIN_EQ_SOME, w64_cast_some, unsigned_v_to_num_some, signed_v_to_int_some, mk_ptr_some] >> rw [sizeof_bits_def, translate_ty_def, translate_size_def] >> rfs [] >> fs [v_rel_cases] >> rw [] >> qmatch_assum_abbrev_tac `eval_exp _ _ (FlatV (IntV i s))` >> qexists_tac `s` >> qexists_tac `i` >> rw [] >> unabbrev_all_tac >> fs [good_cast_def, translate_ty_def, sizeof_bits_def, translate_size_def] >> rw [trunc_thms, w2w_i2w] >> irule (GSYM w2i_i2w) >- ( `w2i w ≤ INT_MAX (:1) ∧ INT_MIN (:1) ≤ w2i w` by metis_tac [w2i_le, w2i_ge] >> fs [] >> intLib.COOPER_TAC) >- ( `w2i w ≤ INT_MAX (:1) ∧ INT_MIN (:1) ≤ w2i w` by metis_tac [w2i_le, w2i_ge] >> fs [] >> intLib.COOPER_TAC) >- ( `w2i w ≤ INT_MAX (:1) ∧ INT_MIN (:1) ≤ w2i w` by metis_tac [w2i_le, w2i_ge] >> fs [] >> intLib.COOPER_TAC) >- ( `w2i w ≤ INT_MAX (:8) ∧ INT_MIN (:8) ≤ w2i w` by metis_tac [w2i_le, w2i_ge] >> fs [] >> intLib.COOPER_TAC) >- ( `w2i w ≤ INT_MAX (:8) ∧ INT_MIN (:8) ≤ w2i w` by metis_tac [w2i_le, w2i_ge] >> fs [] >> intLib.COOPER_TAC) >- ( `w2i w ≤ INT_MAX (:32) ∧ INT_MIN (:32) ≤ w2i w` by metis_tac [w2i_le, w2i_ge] >> fs [] >> intLib.COOPER_TAC)) (* TODO: pointer to int and int to pointer casts *) >> cheat QED Theorem const_idx_uses[simp]: ∀cs gmap e. exp_uses (foldl (λe c. Select e (translate_const gmap c)) e cs) = exp_uses e Proof Induct_on `cs` >> rw [exp_uses_def] >> rw [EXTENSION] QED Theorem exp_uses_trans_upd_val[simp]: ∀cs gmap e1 e2. exp_uses (translate_updatevalue gmap e1 e2 cs) = (if cs = [] then {} else exp_uses e1) ∪ exp_uses e2 Proof Induct_on `cs` >> rw [exp_uses_def, translate_updatevalue_def] >> rw [EXTENSION] >> metis_tac [] QED (* TODO: identify some lemmas to cut down on the duplicated proof in the very * similar cases *) Theorem translate_instr_to_exp_correct: ∀gmap emap instr r t s1 s1' s2 prog l regs_to_keep. prog_ok prog ∧ is_ssa prog ∧ good_emap s1.ip.f prog regs_to_keep gmap emap ∧ classify_instr instr = Exp r t ∧ mem_state_rel prog gmap emap s1 s1' ∧ get_instr prog s1.ip (Inl instr) ∧ step_instr prog s1 instr l s2 ∧ is_implemented instr ⇒ ∃pv s2'. l = Tau ∧ s2.ip = inc_pc s1.ip ∧ mem_state_rel prog gmap emap s2 s2' ∧ (r ∉ regs_to_keep ⇒ s1' = s2') ∧ (r ∈ regs_to_keep ⇒ step_inst s1' (Move [(translate_reg r t, translate_instr_to_exp gmap emap instr)]) Tau s2') Proof recInduct translate_instr_to_exp_ind >> simp [translate_instr_to_exp_def, classify_instr_def] >> conj_tac >- ( (* Sub *) rw [step_instr_cases, get_instr_cases, update_result_def] >> qpat_x_assum `Sub _ _ _ _ _ _ = el _ _` (assume_tac o GSYM) >> `bigunion (image arg_to_regs {a1; a2}) ⊆ live prog s1.ip` by ( simp [Once live_gen_kill, SUBSET_DEF, uses_cases, IN_DEF, get_instr_cases, instr_uses_def] >> metis_tac []) >> fs [] >> first_x_assum (mp_then.mp_then mp_then.Any mp_tac translate_arg_correct) >> disch_then drule >> disch_then drule >> first_x_assum (mp_then.mp_then mp_then.Any mp_tac translate_arg_correct) >> disch_then drule >> disch_then drule >> rw [] >> drule translate_sub_correct >> simp [] >> disch_then (qspecl_then [`s1'`, `v'`, `v''`] mp_tac) >> simp [] >> disch_then drule >> disch_then drule >> rw [] >> rename1 `eval_exp _ (Sub _ _ _) res_v` >> rename1 `r ∈ _` >> simp [inc_pc_def, llvmTheory.inc_pc_def] >> `assigns prog s1.ip = {(r,ty)}` by rw [assigns_cases, EXTENSION, IN_DEF, get_instr_cases, instr_assigns_def] >> `reachable prog s1.ip` by fs [mem_state_rel_def] >> `s1.ip with i := inc_bip (Offset idx) ∈ next_ips prog s1.ip` by ( drule prog_ok_nonterm >> simp [get_instr_cases, PULL_EXISTS] >> ntac 3 (disch_then drule) >> simp [terminator_def, next_ips_cases, IN_DEF, inc_pc_def]) >> Cases_on `r ∉ regs_to_keep` >> rw [] >- ( irule mem_state_rel_update >> rw [] >- ( fs [get_instr_cases, classify_instr_def, translate_instr_to_exp_def] >> metis_tac []) >- metis_tac []) >- ( simp [step_inst_cases, PULL_EXISTS] >> qexists_tac `res_v` >> rw [] >> rw [update_results_def, GSYM FUPDATE_EQ_FUPDATE_LIST] >> irule mem_state_rel_update_keep >> rw [] >> qexists_tac `regs_to_keep` >> rw [] >> CCONTR_TAC >> fs [] >> drule exp_assigns_sing >> disch_then drule >> rw [] >> metis_tac [])) >> conj_tac >- ( (* Extractvalue *) rw [step_instr_cases, get_instr_cases, update_result_def] >> qpat_x_assum `Extractvalue _ _ _ = el _ _` (assume_tac o GSYM) >> `arg_to_regs a ⊆ live prog s1.ip` by ( simp [Once live_gen_kill, SUBSET_DEF, uses_cases, IN_DEF, get_instr_cases, instr_uses_def]) >> drule translate_extract_correct >> rpt (disch_then drule) >> drule translate_arg_correct >> disch_then drule >> simp [] >> strip_tac >> disch_then drule >> simp [] >> rw [] >> rename1 `eval_exp _ (foldl _ _ _) res_v` >> rw [inc_pc_def, llvmTheory.inc_pc_def] >> rename1 `r ∈ _` >> `assigns prog s1.ip = {(r,THE (extract_type t (map cidx_to_num cs)))}` by rw [assigns_cases, EXTENSION, IN_DEF, get_instr_cases, instr_assigns_def] >> `reachable prog s1.ip` by fs [mem_state_rel_def] >> `s1.ip with i := inc_bip (Offset idx) ∈ next_ips prog s1.ip` by ( drule prog_ok_nonterm >> simp [get_instr_cases, PULL_EXISTS] >> ntac 3 (disch_then drule) >> simp [terminator_def, next_ips_cases, IN_DEF, inc_pc_def]) >> Cases_on `r ∈ regs_to_keep` >> rw [] >- ( simp [step_inst_cases, PULL_EXISTS] >> qexists_tac `res_v` >> rw [] >> rw [update_results_def, GSYM FUPDATE_EQ_FUPDATE_LIST] >> irule mem_state_rel_update_keep >> rw [] >> qexists_tac `regs_to_keep` >> rw [] >> CCONTR_TAC >> fs [] >> drule exp_assigns_sing >> disch_then drule >> rw [] >> metis_tac []) >- ( irule mem_state_rel_update >> rw [] >- ( fs [get_instr_cases, classify_instr_def, translate_instr_to_exp_def] >> metis_tac []) >- metis_tac [])) >> conj_tac >- ( (* Updatevalue *) rw [step_instr_cases, get_instr_cases, update_result_def] >> qpat_x_assum `Insertvalue _ _ _ _ = el _ _` (assume_tac o GSYM) >> `arg_to_regs a1 ⊆ live prog s1.ip ∧ arg_to_regs a2 ⊆ live prog s1.ip` by ( ONCE_REWRITE_TAC [live_gen_kill] >> simp [SUBSET_DEF, uses_cases, IN_DEF, get_instr_cases, instr_uses_def]) >> drule translate_update_correct >> rpt (disch_then drule) >> first_x_assum (mp_then.mp_then mp_then.Any mp_tac translate_arg_correct) >> disch_then drule >> disch_then drule >> first_x_assum (mp_then.mp_then mp_then.Any mp_tac translate_arg_correct) >> disch_then drule >> disch_then drule >> simp [] >> strip_tac >> strip_tac >> disch_then (qspecl_then [`v'`, `v''`] mp_tac) >> simp [] >> disch_then drule >> disch_then drule >> rw [] >> rename1 `eval_exp _ (translate_updatevalue _ _ _ _) res_v` >> rw [inc_pc_def, llvmTheory.inc_pc_def] >> rename1 `r ∈ _` >> `assigns prog s1.ip = {(r,t1)}` by rw [assigns_cases, EXTENSION, IN_DEF, get_instr_cases, instr_assigns_def] >> `reachable prog s1.ip` by fs [mem_state_rel_def] >> `s1.ip with i := inc_bip (Offset idx) ∈ next_ips prog s1.ip` by ( drule prog_ok_nonterm >> simp [get_instr_cases, PULL_EXISTS] >> ntac 3 (disch_then drule) >> simp [terminator_def, next_ips_cases, IN_DEF, inc_pc_def]) >> Cases_on `r ∈ regs_to_keep` >> rw [] >- ( simp [step_inst_cases, PULL_EXISTS] >> qexists_tac `res_v` >> rw [] >> rw [update_results_def, GSYM FUPDATE_EQ_FUPDATE_LIST] >> irule mem_state_rel_update_keep >> rw [] >> qexists_tac `regs_to_keep` >> rw [] >> CCONTR_TAC >> fs [] >> drule exp_assigns_sing >> disch_then drule >> rw [] >> metis_tac []) >- ( irule mem_state_rel_update >> rw [] >- ( fs [get_instr_cases, classify_instr_def, translate_instr_to_exp_def] >> metis_tac []) >- metis_tac [])) >> conj_tac >- ( (* Cast *) simp [step_instr_cases, get_instr_cases, update_result_def] >> rpt strip_tac >> qpat_x_assum `Cast _ _ _ _ = el _ _` (assume_tac o GSYM) >> `arg_to_regs a1 ⊆ live prog s1.ip` by ( simp [Once live_gen_kill, SUBSET_DEF, uses_cases, IN_DEF, get_instr_cases, instr_uses_def] >> metis_tac []) >> fs [] >> first_x_assum (mp_then.mp_then mp_then.Any mp_tac translate_arg_correct) >> disch_then drule >> disch_then drule >> strip_tac >> drule translate_cast_correct >> ntac 2 (disch_then drule) >> simp [] >> disch_then (qspec_then `sizeof_bits (translate_ty t1)` mp_tac) >> impl_tac (* TODO: prog_ok should enforce that the type is consistent *) >- cheat >> strip_tac >> rename1 `eval_exp _ _ res_v` >> simp [inc_pc_def, llvmTheory.inc_pc_def] >> rename1 `r ∈ _` >> `assigns prog s1.ip = {(r,t)}` by rw [assigns_cases, EXTENSION, IN_DEF, get_instr_cases, instr_assigns_def] >> `reachable prog s1.ip` by fs [mem_state_rel_def] >> `s1.ip with i := inc_bip (Offset idx) ∈ next_ips prog s1.ip` by ( drule prog_ok_nonterm >> simp [get_instr_cases, PULL_EXISTS] >> ntac 3 (disch_then drule) >> simp [terminator_def, next_ips_cases, IN_DEF, inc_pc_def]) >> Cases_on `r ∈ regs_to_keep` >> simp [] >- ( simp [step_inst_cases, PULL_EXISTS] >> qexists_tac `res_v` >> rw [] >> fs [] >> rw [update_results_def, GSYM FUPDATE_EQ_FUPDATE_LIST] >> irule mem_state_rel_update_keep >> rw [] >> qexists_tac `regs_to_keep` >> rw [] >> CCONTR_TAC >> fs [] >> drule exp_assigns_sing >> disch_then drule >> rw [] >> metis_tac []) >- ( irule mem_state_rel_update >> rw [] >- ( fs [get_instr_cases, classify_instr_def, translate_instr_to_exp_def] >> metis_tac []) >- metis_tac [])) >> rw [is_implemented_def] QED Triviality eval_exp_help: (s1 with heap := h).locals = s1.locals Proof rw [] QED Theorem translate_instr_to_inst_correct: ∀gmap emap instr r t s1 s1' s2 prog l regs_to_keep. classify_instr instr = Non_exp ∧ prog_ok prog ∧ is_ssa prog ∧ good_emap s1.ip.f prog regs_to_keep gmap emap ∧ mem_state_rel prog gmap emap s1 s1' ∧ get_instr prog s1.ip (Inl instr) ∧ step_instr prog s1 instr l s2 ⇒ ∃pv s2'. s2.ip = inc_pc s1.ip ∧ mem_state_rel prog gmap emap s2 s2' ∧ step_inst s1' (translate_instr_to_inst gmap emap instr) (translate_trace gmap l) s2' Proof rw [step_instr_cases] >> fs [classify_instr_def, translate_instr_to_inst_def] >- ( (* Load *) fs [step_inst_cases, get_instr_cases, PULL_EXISTS] >> qpat_x_assum `Load _ _ _ = el _ _` (assume_tac o GSYM) >> `arg_to_regs a1 ⊆ live prog s1.ip` by ( simp [Once live_gen_kill, SUBSET_DEF, uses_cases, IN_DEF, get_instr_cases, instr_uses_def] >> metis_tac []) >> fs [] >> first_x_assum (mp_then.mp_then mp_then.Any mp_tac translate_arg_correct) >> disch_then drule >> disch_then drule >> rw [] >> qpat_x_assum `v_rel (FlatV _) _` mp_tac >> simp [Once v_rel_cases] >> rw [] >> `∃n. r = Reg n` by (Cases_on `r` >> metis_tac []) >> qexists_tac `n` >> qexists_tac `translate_ty t` >> HINT_EXISTS_TAC >> rw [] >> qexists_tac `freeable` >> rw [translate_trace_def] >- rw [inc_pc_def, llvmTheory.inc_pc_def, update_result_def] >- ( simp [GSYM translate_reg_def, llvmTheory.inc_pc_def, update_result_def, update_results_def, GSYM FUPDATE_EQ_FUPDATE_LIST, extend_emap_non_exp_def] >> irule mem_state_rel_update_keep >> rw [] >- rw [assigns_cases, IN_DEF, EXTENSION, get_instr_cases, instr_assigns_def] >- ( `s1.ip with i := inc_bip (Offset idx) = inc_pc s1.ip` by rw [inc_pc_def] >> simp [] >> irule prog_ok_nonterm >> simp [get_instr_cases, terminator_def]) >- metis_tac [next_ips_reachable, mem_state_rel_def] >- ( fs [w2n_i2n, pointer_size_def, mem_state_rel_def] >> metis_tac [bytes_v_rel, get_bytes_erase_tags]) >- ( qexists_tac `regs_to_keep` >> rw [] >> CCONTR_TAC >> fs [get_instr_cases] >> fs [] >> rw [] >> fs [] >> rw [] >> rfs [classify_instr_def])) >- rw [translate_reg_def] >- ( fs [w2n_i2n, pointer_size_def, mem_state_rel_def] >> metis_tac [is_allocated_erase_tags])) >- ( (* Store *) fs [step_inst_cases, get_instr_cases, PULL_EXISTS] >> qpat_x_assum `Store _ _ = el _ _` (assume_tac o GSYM) >> `bigunion (image arg_to_regs {a1; a2}) ⊆ live prog s1.ip` by ( simp [Once live_gen_kill, SUBSET_DEF, uses_cases, IN_DEF, get_instr_cases, instr_uses_def] >> metis_tac []) >> fs [] >> first_x_assum (mp_then.mp_then mp_then.Any mp_tac translate_arg_correct) >> disch_then drule >> disch_then drule >> first_x_assum (mp_then.mp_then mp_then.Any mp_tac translate_arg_correct) >> disch_then drule >> disch_then drule >> rw [] >> qpat_x_assum `v_rel (FlatV _) _` mp_tac >> simp [Once v_rel_cases] >> rw [] >> drule v_rel_bytes >> rw [] >> fs [w2n_i2n, pointer_size_def] >> HINT_EXISTS_TAC >> rw [] >> qexists_tac `freeable` >> rw [] >> qexists_tac `v'` >> rw [] >- rw [llvmTheory.inc_pc_def, inc_pc_def] >- ( simp [llvmTheory.inc_pc_def] >> irule mem_state_rel_no_update >> rw [] >- rw [assigns_cases, EXTENSION, IN_DEF, get_instr_cases, instr_assigns_def] >- ( `s1.ip with i := inc_bip (Offset idx) = inc_pc s1.ip` by rw [inc_pc_def] >> simp [] >> irule prog_ok_nonterm >> simp [get_instr_cases, terminator_def]) >> irule mem_state_rel_heap_update >> rw [set_bytes_unchanged, erase_tags_set_bytes] >> fs [mem_state_rel_def, extend_emap_non_exp_def] >> metis_tac [set_bytes_heap_ok]) >- ( fs [mem_state_rel_def] >> fs [is_allocated_def, heap_component_equality, erase_tags_def] >> metis_tac []) >- ( fs [get_obs_cases, llvmTheory.get_obs_cases] >> rw [translate_trace_def] >> fs [mem_state_rel_def, globals_rel_def] >- ( fs [FLOOKUP_DEF] >> first_x_assum drule >> rw [] >- metis_tac [BIJ_DEF, SURJ_DEF] >> pop_assum (mp_tac o GSYM) >> rw [w2n_i2n]) >- ( CCONTR_TAC >> fs [FRANGE_DEF] >> fs [BIJ_DEF, SURJ_DEF, INJ_DEF] >> first_x_assum drule >> rw [] >> CCONTR_TAC >> fs [] >> rw [] >> first_x_assum drule >> rw [] >> CCONTR_TAC >> fs [] >> rw [] >> `i2n (IntV (w2i w) (dimindex (:64))) = w2n w` by metis_tac [w2n_i2n, dimindex_64] >> fs [] >> rw [] >> fs [METIS_PROVE [] ``~x ∨ y ⇔ (x ⇒ y)``] >> first_x_assum drule >> rw [] >> metis_tac [pair_CASES, SND]))) QED Theorem classify_instr_term_call: ∀i. (classify_instr i = Term ⇒ terminator i) ∧ (classify_instr i = Call ⇒ is_call i ∨ terminator i) Proof Cases >> rw [classify_instr_def, is_call_def, terminator_def] >> Cases_on `p` >> rw [classify_instr_def] QED Definition untranslate_glob_var_def: untranslate_glob_var (Var_name n ty) = Glob_var n End Definition untranslate_trace_def: (untranslate_trace Tau = Tau) ∧ (untranslate_trace Error = Error) ∧ (untranslate_trace (Exit i) = (Exit i)) ∧ (untranslate_trace (W gv bytes) = W (untranslate_glob_var gv) bytes) End Theorem un_translate_glob_inv: ∀x t. untranslate_glob_var (translate_glob_var gmap x) = x Proof Cases_on `x` >> rw [translate_glob_var_def] >> CASE_TAC >> rw [untranslate_glob_var_def] QED Theorem un_translate_trace_inv: ∀x. untranslate_trace (translate_trace gmap x) = x Proof Cases >> rw [translate_trace_def, untranslate_trace_def] >> metis_tac [un_translate_glob_inv] QED Theorem take_to_call_lem: ∀i idx body. idx < length body ∧ el idx body = i ∧ ¬terminator i ∧ ¬is_call i ⇒ take_to_call (drop idx body) = i :: take_to_call (drop (idx + 1) body) Proof Induct_on `idx` >> rw [] >- (Cases_on `body` >> fs [take_to_call_def] >> rw []) >> Cases_on `body` >> fs [] >> simp [ADD1] QED Theorem inc_translate_label: ∀f l x. inc_label (translate_label f l x) = translate_label f l (x + 1) Proof rw [] >> Cases_on `l` >> rw [translate_label_def, inc_label_def] >> Cases_on `x'` >> rw [translate_label_def, inc_label_def] QED Theorem translate_instrs_correct1: ∀prog s1 tr s2. multi_step prog s1 tr s2 ⇒ ∀s1' regs_to_keep b' gmap emap d b idx rest l. prog_ok prog ∧ is_ssa prog ∧ mem_state_rel prog gmap emap s1 s1' ∧ good_emap s1.ip.f prog regs_to_keep gmap emap ∧ alookup prog s1.ip.f = Some d ∧ alookup d.blocks s1.ip.b = Some b ∧ s1.ip.i = Offset idx ∧ (l,b')::rest = fst (translate_instrs (translate_label (dest_fn s1.ip.f) s1.ip.b (num_calls (take idx b.body))) gmap emap regs_to_keep (take_to_call (drop idx b.body))) ∧ every is_implemented b.body ⇒ ∃s2' tr'. step_block (translate_prog prog) s1' b'.cmnd b'.term tr' s2' ∧ filter ($≠ Tau) tr' = filter ($≠ Tau) (map (translate_trace gmap) tr) ∧ state_rel prog gmap emap s2 s2' Proof ho_match_mp_tac multi_step_ind >> rw_tac std_ss [] >- ( fs [last_step_cases] >- ( (* Phi (not handled here) *) fs [get_instr_cases]) >- ( (* Terminator *) rename1 `Inl instr` >> `is_implemented instr` by (fs [get_instr_cases] >> metis_tac [EVERY_MEM, EL_MEM]) >> `(∃code. l = Exit code) ∨ l = Tau ` by ( fs [llvmTheory.step_cases] >> `i' = instr` by metis_tac [get_instr_func, INL_11] >> fs [step_instr_cases] >> rfs [terminator_def]) >> fs [get_instr_cases, translate_trace_def] >> rw [] >> `el idx b.body = el 0 (drop idx b.body)` by rw [EL_DROP] >> fs [] >> Cases_on `drop idx b.body` >> fs [DROP_NIL] >> rw [] >- ( (* Exit *) fs [llvmTheory.step_cases, get_instr_cases, step_instr_cases, translate_instrs_def, take_to_call_def, classify_instr_def, translate_instr_to_term_def, translate_instr_to_inst_def, llvmTheory.get_obs_cases] >> simp [Once step_block_cases, step_term_cases, PULL_EXISTS, step_inst_cases] >> drule translate_arg_correct >> disch_then drule >> impl_tac >- ( `get_instr prog s1.ip (Inl (Exit a))` by rw [get_instr_cases] >> drule get_instr_live >> simp [uses_cases, SUBSET_DEF, IN_DEF, PULL_EXISTS] >> rw [] >> first_x_assum irule >> disj1_tac >> metis_tac [instr_uses_def]) >> rw [] >> qexists_tac `s1' with status := Complete code` >> qexists_tac `[Exit code]` >> rw [] >- ( rfs [translate_instrs_def, classify_instr_def] >> rw [translate_instr_to_term_def] >> fs [v_rel_cases] >> fs [signed_v_to_int_def] >> metis_tac []) >> rw [state_rel_def] >> metis_tac [mem_state_rel_exited]) >> fs [take_to_call_def] >> rfs [] >> fs [translate_instrs_def] >> Cases_on `el idx b.body` >> fs [terminator_def, classify_instr_def, translate_trace_def] >> rw [] >- fs [is_implemented_def] >- ( (* Br *) simp [translate_instr_to_term_def, Once step_block_cases] >> simp [step_term_cases, PULL_EXISTS, RIGHT_AND_OVER_OR, EXISTS_OR_THM] >> pairarg_tac >> rw [] >> fs [llvmTheory.step_cases] >> drule get_instr_live >> disch_tac >> drule translate_arg_correct >> fs [step_instr_cases] >> fs [] >> TRY (fs [get_instr_cases] >> NO_TAC) >> `a = a'` by fs [get_instr_cases] >> disch_then drule >> impl_tac >- ( fs [SUBSET_DEF, IN_DEF] >> rfs [uses_cases, get_instr_cases, instr_uses_def] >> fs [IN_DEF]) >> disch_tac >> fs [] >> fs [v_rel_cases, GSYM PULL_EXISTS] >> GEN_EXISTS_TAC "idx'" `w2i tf` >> simp [GSYM PULL_EXISTS] >> conj_tac >- metis_tac [] >> rename1 `el _ _ = Br e lab1 lab2` >> qpat_abbrev_tac `target = if tf = 0w then l2 else l1` >> `last b.body = Br e l1 l2 ∧ <|f := s1.ip.f; b := Some target; i := Phi_ip s1.ip.b|> ∈ next_ips prog s1.ip` by ( fs [prog_ok_def, get_instr_cases] >> last_x_assum drule >> disch_then drule >> strip_tac >> conj_asm1_tac >- ( CCONTR_TAC >> `Br a l1 l2 ∈ set (front (b.body))` by ( `mem (Br a l1 l2) (front b.body ++ [last b.body])` by metis_tac [EL_MEM, APPEND_FRONT_LAST] >> fs [] >> metis_tac []) >> fs [EVERY_MEM] >> first_x_assum drule >> rw [terminator_def]) >- ( rw [next_ips_cases, IN_DEF, assigns_cases] >> disj1_tac >> qexists_tac `Br a l1 l2` >> rw [instr_next_ips_def, Abbr `target`] >> fs [get_instr_cases, instr_to_labs_def] >> metis_tac [blockHeader_nchotomy])) >> qmatch_goalsub_abbrev_tac `state_rel _ _ _ _ (_ with bp := target')` >> rw [state_rel_def] >- ( fs [get_instr_cases] >> `every (λlab. ∃b phis landing. alookup d.blocks (Some lab) = Some b ∧ b.h = Head phis landing) (instr_to_labs (last b.body))` by (fs [prog_ok_def, EVERY_MEM] >> metis_tac []) >> rfs [instr_to_labs_def] >> rw [Once pc_rel_cases, get_instr_cases, get_block_cases, PULL_EXISTS] >> fs [GSYM PULL_EXISTS, Abbr `target`] >> rw [MEM_MAP, instr_to_labs_def] >> `s1.ip.b = option_map Lab l' ∧ dest_fn s1.ip.f = f` by ( Cases_on `s1.ip.b` >> fs [translate_label_def] >> Cases_on `x` >> fs [translate_label_def]) >> rw [OPTION_MAP_COMPOSE, combinTheory.o_DEF, dest_label_def, Abbr `target'`, word_0_w2i, METIS_PROVE [w2i_eq_0] ``∀w. 0 = w2i w ⇔ w = 0w``] >> TRY (Cases_on `l'` >> rw [] >> NO_TAC)) >- ( fs [mem_state_rel_def, local_state_rel_def, emap_invariant_def] >> rw [] >- ( qpat_x_assum `∀r. r ∈ live _ _ ⇒ P r` mp_tac >> simp [Once live_gen_kill] >> disch_then (qspec_then `r` mp_tac) >> impl_tac >> rw [] >> rw [PULL_EXISTS] >> disj1_tac >> qexists_tac `<|f := s1.ip.f; b := Some target; i := Phi_ip s1.ip.b|>` >> rw [] >> rw [IN_DEF, assigns_cases] >> CCONTR_TAC >> fs [] >> imp_res_tac get_instr_func >> fs [] >> rw [] >> fs [instr_assigns_def]) >- ( fs [reachable_def] >> qexists_tac `path ++ [<|f := s1.ip.f; b := Some target; i := Phi_ip s1.ip.b|>]` >> rw_tac std_ss [good_path_append, GSYM APPEND] >> rw [] >- (rw [Once good_path_cases] >> fs [next_ips_cases, IN_DEF] >> metis_tac []) >- metis_tac [ip_equiv_next_ips, ip_equiv_sym] >- metis_tac [ip_equiv_refl]))) >- fs [is_implemented_def] >- fs [is_implemented_def] >- ( (* Exit *) fs [llvmTheory.step_cases, get_instr_cases, step_instr_cases]) >- fs [is_implemented_def]) >- ( (* Call *) rename1 `Inl instr` >> `is_implemented instr` by (fs [get_instr_cases] >> metis_tac [EVERY_MEM, EL_MEM]) >> Cases_on `instr` >> fs [is_call_def, is_implemented_def]) >- ( (* Stuck *) rw [translate_trace_def] >> (* TODO: need to know that stuck LLVM instructions translate to stuck * llair instructions. This will follow from knowing that when a llair * instruction takes a step, the LLVM source can take the same step, ie, * the backward direction of the proof. *) cheat)) >- ( (* Middle of the block *) fs [llvmTheory.step_cases] >> TRY (fs [get_instr_cases] >> NO_TAC) >> `i' = i` by metis_tac [get_instr_func, INL_11] >> fs [] >> rename [`step_instr _ _ _ _ s2`, `state_rel _ _ _ s3 _`, `mem_state_rel _ _ _ s1 s1'`] >> Cases_on `∃r t. classify_instr i = Exp r t` >> fs [] >> `is_implemented i` by (fs [get_instr_cases] >> metis_tac [EVERY_MEM, EL_MEM]) >- ( (* instructions that compile to expressions *) drule translate_instr_to_exp_correct >> ntac 6 (disch_then drule) >> rw [] >> fs [translate_trace_def] >> `reachable prog (inc_pc s1.ip)` by metis_tac [prog_ok_nonterm, next_ips_reachable, mem_state_rel_def] >> first_x_assum drule >> simp [inc_pc_def, inc_bip_def] >> disch_then drule >> `take_to_call (drop idx b.body) = i :: take_to_call (drop (idx + 1) b.body)` by ( irule take_to_call_lem >> simp [] >> fs [get_instr_cases]) >> `num_calls (take (idx + 1) b.body) = num_calls (take idx b.body)` by (fs [get_instr_cases] >> rw [num_calls_def, TAKE_EL_SNOC, FILTER_SNOC]) >> fs [translate_instrs_def, inc_translate_label] >> Cases_on `r ∉ regs_to_keep` >> fs [] >> rw [] >- ( `emap = emap |+ (r,translate_instr_to_exp gmap emap i)` by ( fs [good_emap_def, fmap_eq_flookup, FLOOKUP_UPDATE] >> rw [] >> metis_tac []) >> metis_tac []) >> pairarg_tac >> fs [] >> rw [] >> `emap |+ (r,Var (translate_reg r t) F) = emap` by ( fs [good_emap_def, fmap_eq_flookup, FLOOKUP_UPDATE] >> rw [] >> `(r,t) ∈ assigns prog s1.ip` by ( drule exp_assigns_sing >> disch_then drule >> rw []) >> metis_tac [FST, SND, not_exp_def]) >> fs [] >> rename1 `translate_instrs _ _ _ _ _ = (bs, emap1)` >> Cases_on `bs` >> fs [add_to_first_block_def] >> rename1 `translate_instrs _ _ _ _ _ = (b1::bs, _)` >> Cases_on `b1` >> fs [add_to_first_block_def] >> rw [] >> rename1 `state_rel prog gmap emap3 s3 s3'` >> qexists_tac `s3'` >> rw [] >> qexists_tac `Tau::tr'` >> rw [] >> simp [Once step_block_cases] >> metis_tac []) >- ( (* Non-expression instructions *) Cases_on `classify_instr i` >> fs [classify_instr_term_call] >- ( drule translate_instr_to_inst_correct >> ntac 6 (disch_then drule) >> strip_tac >> fs [] >> first_x_assum drule >> simp [inc_pc_def, inc_bip_def] >> disch_then (qspecl_then [`regs_to_keep`] mp_tac) >> simp [] >> strip_tac >> `take_to_call (drop idx b.body) = i :: take_to_call (drop (idx + 1) b.body)` by ( irule take_to_call_lem >> simp [] >> fs [get_instr_cases]) >> `num_calls (take (idx + 1) b.body) = num_calls (take idx b.body)` by (fs [get_instr_cases] >> rw [num_calls_def, TAKE_EL_SNOC, FILTER_SNOC]) >> fs [translate_instrs_def, inc_translate_label] >> pairarg_tac >> fs [] >> `extend_emap_non_exp emap i = emap` by ( Cases_on `∀r t. instr_assigns i ≠ {(r,t)}` >- metis_tac [extend_emap_non_exp_no_assigns] >> fs [] >> drule extend_emap_non_exp_assigns >> rw [] >> fs [good_emap_def] >> first_x_assum (qspec_then `s1.ip` mp_tac) >> rw [] >> last_x_assum (qspec_then `i` mp_tac) >> simp [not_exp_def] >> disch_then (qspec_then `(r,t)` mp_tac) >> impl_tac >- ( fs [IN_DEF, assigns_cases, EXTENSION] >> metis_tac []) >> rw [fmap_eq_flookup, FLOOKUP_UPDATE] >> rw [] >> rw []) >> fs [] >> rename1 `translate_instrs _ _ _ _ _ = (bs, emap1)` >> Cases_on `bs` >> fs [add_to_first_block_def] >> rename1 `translate_instrs _ _ _ _ _ = (b1::bs, _)` >> Cases_on `b1` >> fs [add_to_first_block_def] >> fs [] >> rw [] >> rename1 `state_rel prog gmap emap3 s3 s3'` >> qexists_tac `s3'` >> simp [] >> qexists_tac `translate_trace gmap l::tr'` >> rw [] >> simp [Once step_block_cases] >- (disj2_tac >> qexists_tac `s2'` >> rw []) >- (disj2_tac >> qexists_tac `s2'` >> rw []) >- metis_tac []) >- metis_tac [classify_instr_term_call])) QED Theorem do_phi_vals: ∀prog gmap emap from_l s s' phis updates. mem_state_rel prog gmap emap s s' ∧ list_rel (do_phi from_l s) phis updates ∧ BIGUNION (set (map (phi_uses from_l) phis)) ⊆ live prog s.ip ⇒ ∃es vs. list_rel v_rel (map (λx. (snd x).value) updates) vs ∧ list_rel (eval_exp s') es vs ∧ map fst updates = map fst (map phi_assigns phis) ∧ map (λx. case x of Phi r t largs => case option_map (λarg. translate_arg gmap emap arg) (alookup largs from_l) of None => (translate_reg r t,Nondet) | Some e => (translate_reg r t,e)) phis = map2 (\p. λe. case p of Phi r t largs => (translate_reg r t, e)) phis es Proof Induct_on `phis` >> rw [] >> fs [] >> first_x_assum drule >> disch_then drule >> rw [PULL_EXISTS] >> Cases_on `h` >> fs [do_phi_cases] >> drule translate_arg_correct >> disch_then drule >> impl_tac >- (fs [phi_uses_def] >> rfs []) >> rw [PULL_EXISTS, phi_assigns_def] >> metis_tac [] QED Triviality case_phi_lift: ∀f g. f (case x of Phi x y z => g x y z) = case x of Phi x y z => f (g x y z) Proof Cases_on `x` >> rw [] QED Triviality id2: (λ(v,r). (v,r)) = I Proof rw [FUN_EQ_THM] >> Cases_on `x` >> rw [] QED Theorem build_phi_block_correct_helper[local]: ∀phis es. map (λx. case x of Phi r t largs => case option_map (λarg. translate_arg gmap emap arg) (alookup largs from_l) of None => (translate_reg r t,Nondet) | Some e => (translate_reg r t,e)) phis = map2 (λp e. case p of Phi r t largs => (translate_reg r t,e)) phis es ∧ length phis = length es ⇒ es = map (λx. case x of Phi r t largs => case option_map (λarg. translate_arg gmap emap arg) (alookup largs from_l) of None => Nondet | Some e => e) phis Proof Induct >> rw [] >> Cases_on `es` >> fs [] >> CASE_TAC >> fs [] >> CASE_TAC >> fs [] QED Theorem build_phi_block_correct: ∀prog s1 s1' to_l from_l phis updates f gmap emap entry bloc regs_to_keep. prog_ok prog ∧ is_ssa prog ∧ good_emap s1.ip.f prog regs_to_keep gmap emap ∧ get_instr prog s1.ip (Inr (from_l,phis)) ∧ list_rel (do_phi from_l s1) phis updates ∧ mem_state_rel prog gmap emap s1 s1' ∧ BIGUNION (set (map (phi_uses from_l) phis)) ⊆ live prog s1.ip ∧ bloc = generate_move_block f gmap emap phis from_l to_l ⇒ ∃s2'. s2'.bp = translate_label f (Some to_l) 0 ∧ step_block (translate_prog prog) s1' bloc.cmnd bloc.term [Tau; Tau] s2' ∧ mem_state_rel prog gmap emap (inc_pc (s1 with locals := s1.locals |++ updates)) s2' Proof rw [translate_header_def, generate_move_block_def] >> rw [Once step_block_cases] >> rw [Once step_block_cases] >> rw [step_term_cases, PULL_EXISTS] >> simp [Once eval_exp_cases, truncate_2comp_def] >> drule do_phi_vals >> ntac 2 (disch_then drule) >> rw [] >> drule build_phi_block_correct_helper >> pop_assum kall_tac >> `length phis = length es` by metis_tac [LENGTH_MAP, LIST_REL_LENGTH] >> disch_then drule >> rw [] >> fs [LIST_REL_MAP1, combinTheory.o_DEF, case_phi_lift] >> simp [step_inst_cases, PULL_EXISTS] >> qexists_tac `0` >> qexists_tac `vs` >> rw [] >- ( simp [LIST_REL_MAP1, combinTheory.o_DEF] >> fs [LIST_REL_EL_EQN] >> rw [] >> first_x_assum (qspec_then `n` mp_tac) >> simp [] >> CASE_TAC >> simp [] >> CASE_TAC >> simp [build_move_for_lab_def] >> CASE_TAC >> simp [] >> fs []) >> fs [header_to_emap_upd_def] >> simp [llvmTheory.inc_pc_def, update_results_def] >> `s1.ip with i := inc_bip s1.ip.i ∈ next_ips prog s1.ip` by ( simp [next_ips_cases, IN_DEF, inc_pc_def] >> disj2_tac >> qexists_tac `from_l` >> qexists_tac `phis` >> fs [get_instr_cases, EXISTS_OR_THM, inc_bip_def, prog_ok_def] >> res_tac >> Cases_on `b.body` >> fs []) >> fs [mem_state_rel_def] >> rw [] >- ( first_assum (mp_then.mp_then mp_then.Any mp_tac local_state_rel_updates_keep) >> rpt (disch_then (fn x => first_assum (mp_then.mp_then mp_then.Any mp_tac x))) >> disch_then (qspecl_then [`map (λ(x:phi). case x of Phi r t _ => (r,t)) phis`, `map snd updates`, `vs`] mp_tac) >> simp [] >> impl_tac >> rw [id2] >- ( fs [prog_ok_def] >> first_x_assum drule >> simp [MAP_MAP_o, combinTheory.o_DEF] >> `(λp. case p of Phi r v1 v2 => r) = (λx. fst (case x of Phi r t v2 => (r,t)))` by (rw [FUN_EQ_THM] >> CASE_TAC >> rw []) >> rw []) >- ( rw [EXTENSION, IN_DEF, assigns_cases] >> eq_tac >> rw [] >> fs [LIST_TO_SET_MAP] >- ( disj2_tac >> qexists_tac `from_l` >> qexists_tac `phis` >> rw [] >> HINT_EXISTS_TAC >> CASE_TAC >> rw [phi_assigns_def]) >- metis_tac [get_instr_func, sum_distinct] >- ( rw [] >> rename1 `mem x1 phis1` >> qexists_tac `x1` >> Cases_on `x1` >> rw [phi_assigns_def] >> metis_tac [get_instr_func, INR_11, PAIR_EQ])) >- ( rw [assigns_cases, EXTENSION, IN_DEF] >> metis_tac [get_instr_func, sum_distinct, INR_11, PAIR_EQ]) >- metis_tac [LENGTH_MAP] >- rw [LIST_REL_MAP1, combinTheory.o_DEF] >> `map fst (map (λx. case x of Phi r t v2 => (r,t)) phis) = map fst (map phi_assigns phis)` by (rw [LIST_EQ_REWRITE, EL_MAP] >> CASE_TAC >> rw [phi_assigns_def]) >> fs [MAP_MAP_o, combinTheory.o_DEF, case_phi_lift] >> `zip (map (λx. fst (phi_assigns x)) phis, map snd updates) = updates` by ( qpat_x_assum `map fst _ = map (λx. fst (phi_assigns x)) _` mp_tac >> simp [LIST_EQ_REWRITE, EL_MAP] >> `length phis = length updates` by metis_tac [LIST_REL_LENGTH] >> rw [EL_ZIP, LENGTH_MAP, EL_MAP] >> rename1 `_ = el n updates` >> first_x_assum drule >> Cases_on `el n updates` >> rw []) >> `(λx. case x of Phi r t v2 => translate_reg r t) = (λx. fst (build_move_for_lab gmap emap from_l x))` by ( rw [FUN_EQ_THM] >> CASE_TAC >> rw [build_move_for_lab_def] >> CASE_TAC >> rw []) >> fs []) >- (irule next_ips_reachable >> qexists_tac `s1.ip` >> rw []) QED Theorem translate_instrs_take_to_call: ∀l gmap emap regs body. body ≠ [] ∧ terminator (last body) ⇒ fst (translate_instrs l gmap emap regs (take_to_call body)) = [HD (fst (translate_instrs l gmap emap regs body))] Proof Induct_on `body` >> rw [translate_instrs_def, take_to_call_def] >> rename1 `classify_instr inst` >> Cases_on `classify_instr inst` >> fs [] >> fs [] >> rw [] >> fs [] >- metis_tac [classify_instr_lem, instr_class_distinct] >- metis_tac [classify_instr_lem, instr_class_distinct] >- metis_tac [classify_instr_lem, instr_class_distinct] >- ( Cases_on `body` >> fs [] >- rw [translate_instrs_def] >> pairarg_tac >> rw []) >- metis_tac [classify_instr_lem, instr_class_distinct] >- metis_tac [classify_instr_lem, instr_class_distinct] >- metis_tac [classify_instr_lem, instr_class_distinct] >- ( Cases_on `body` >> fs [] >- rw [translate_instrs_def] >> pairarg_tac >> rw []) >- ( `body ≠ []` by (Cases_on `body` >> fs []) >> fs [LAST_DEF] >> pairarg_tac >> fs [] >> pairarg_tac >> fs [] >> `bs = [HD bs']` by metis_tac [FST] >> Cases_on `bs'` >> fs [] >- metis_tac [translate_instrs_not_empty] >> Cases_on `h` >> fs [add_to_first_block_def]) >- ( `body ≠ []` by (Cases_on `body` >> fs []) >> fs [LAST_DEF] >> pairarg_tac >> fs []) >- ( `body ≠ []` by (Cases_on `body` >> fs []) >> fs [LAST_DEF] >> pairarg_tac >> fs [] >> pairarg_tac >> fs [] >> `bs = [HD bs']` by metis_tac [FST] >> Cases_on `bs'` >> fs [] >- metis_tac [translate_instrs_not_empty] >> Cases_on `h` >> fs [add_to_first_block_def]) >- metis_tac [classify_instr_lem, instr_class_distinct] QED Theorem multi_step_to_step_block: ∀prog emap s1 tr s2 s1'. prog_ok prog ∧ is_ssa prog ∧ dominator_ordered prog ∧ good_emap s1.ip.f prog (get_regs_to_keep (THE (alookup prog s1.ip.f))) (get_gmap prog) emap ∧ multi_step prog s1 tr s2 ∧ s1.status = Partial ∧ state_rel prog (get_gmap prog) emap s1 s1' ∧ every (\(l, d). every (\(l, b). every is_implemented b.body) d.blocks) prog ⇒ ∃s2' b tr'. get_block (translate_prog prog) s1'.bp b ∧ step_block (translate_prog prog) s1' b.cmnd b.term tr' s2' ∧ filter ($≠ Tau) tr' = filter ($≠ Tau) (map (translate_trace (get_gmap prog)) tr) ∧ state_rel prog (get_gmap prog) emap s2 s2' Proof rw [] >> ntac 2 (pop_assum mp_tac) >> simp [Once state_rel_def] >> rw [Once pc_rel_cases] >- ( (* Non-phi instruction *) drule translate_instrs_correct1 >> simp [] >> disch_then drule >> disch_then drule >> rfs [] >> disch_then drule >> impl_tac >- ( fs [EVERY_MEM] >> rw [] >> `mem (s1.ip.f, d) prog` by fs [alookup_some] >> first_x_assum drule >> rw [] >> `mem (s1.ip.b, b) d.blocks` by fs [alookup_some] >> first_x_assum drule >> rw []) >> rw [] >> rename1 `step_block _ s1' b1.cmnd b1.term tr1 s2'` >> qexists_tac `s2'` >> qexists_tac `b1` >> qexists_tac `tr1` >> simp []) >> (* Phi instruction *) reverse (fs [Once multi_step_cases]) >- metis_tac [get_instr_func, sum_distinct] >> qpat_x_assum `last_step _ _ _ _` mp_tac >> simp [last_step_cases] >> strip_tac >- ( fs [llvmTheory.step_cases] >- metis_tac [get_instr_func, sum_distinct] >> fs [translate_trace_def] >> rw [] >> `(from_l', phis') = (from_l, phis) ∧ x = (from_l, phis)` by metis_tac [get_instr_func, INR_11] >> fs [] >> rw [] >> rfs [MEM_MAP] >> Cases_on `s1.ip.f` >> fs [dest_fn_def] >> drule get_block_translate_prog_mov >> rpt (disch_then drule) >> rw [PULL_EXISTS] >> `∃block l. alookup d.blocks (Some (Lab to_l)) = Some block ∧ block.h = Head phis l` by ( fs [prog_ok_def, EVERY_MEM] >> last_x_assum drule >> disch_then drule >> rw [] >> first_x_assum drule >> rw [] >> rw [] >> fs [get_instr_cases] >> rfs [] >> rw [] >> fs []) >> `every (λ(l,b). every is_implemented b.body) d.blocks` by ( `mem (Fn s, d) prog` by fs [alookup_some] >> fs [EVERY_MEM] >> rw [] >> pairarg_tac >> fs [] >> rw [] >> first_x_assum drule >> simp [] >> disch_then drule >> simp []) >> first_x_assum drule >> rw [] >> qmatch_assum_abbrev_tac `get_block _ _ bloc` >> GEN_EXISTS_TAC "b" `bloc` >> rw [] >> qpat_x_assum `_ = Fn _` (assume_tac o GSYM) >> fs [] >> drule build_phi_block_correct >> rpt (disch_then drule) >> simp [Abbr `bloc`] >> disch_then (qspecl_then [`Lab to_l`, `s`] mp_tac) >> simp [] >> impl_tac >- ( drule get_instr_live >> rw [SUBSET_DEF, uses_cases, IN_DEF] >> first_x_assum irule >> disj2_tac >> metis_tac []) >> rw [] >> qexists_tac `s2'` >> rw [CONJ_ASSOC, LEFT_EXISTS_AND_THM, RIGHT_EXISTS_AND_THM] >- (qexists_tac `[Tau; Tau]` >> rw []) >> fs [state_rel_def] >> rw [] >> fs [llvmTheory.inc_pc_def] >> fs [pc_rel_cases, get_instr_cases, PULL_EXISTS, translate_label_def, dest_fn_def, inc_bip_def, label_to_fname_def] >> fs [] >> rw [] >> fs [get_block_cases, PULL_EXISTS, label_to_fname_def] >> rfs [] >> rw [] >> qpat_x_assum `Fn _ = _` (assume_tac o GSYM) >> fs [] >> drule alookup_translate_prog >> rw [] >> rw [GSYM PULL_EXISTS, dest_fn_def] >- (fs [prog_ok_def] >> res_tac >> fs [] >> Cases_on `b'.body` >> fs []) >> rw [PULL_EXISTS, translate_def_def] >> `b'.body ≠ [] ∧ terminator (last b'.body) ∧ every (λi. ¬terminator i) (front b'.body) ∧ every (λb. (snd b).h = Entry ⇔ fst b = None) d.blocks ∧ 0 ≤ num_calls b'.body` by ( fs [prog_ok_def] >> res_tac >> fs [] >> fs [EVERY_MEM]) >> qmatch_goalsub_abbrev_tac `translate_blocks f gmap _ regs edg _` >> `translate_blocks f gmap fempty regs edg d.blocks = translate_blocks f gmap emap regs edg d.blocks` by ( irule translate_blocks_emap_restr_live >> unabbrev_all_tac >> rw [] >- metis_tac [prog_ok_terminator_last] >- ( fs [prog_ok_def] >> fs [EVERY_MEM] >> rw [] >> pairarg_tac >> rw [] >> metis_tac [FST, SND]) >- metis_tac [dominator_ordered_linear_live, similar_emap_def, DRESTRICT_IS_FEMPTY]) >> rw [] >> drule alookup_translate_blocks >> rpt (disch_then drule) >> impl_tac >- ( fs [prog_ok_def, EVERY_MEM] >> rw [] >> irule ALOOKUP_ALL_DISTINCT_MEM >> rw [] >> imp_res_tac ALOOKUP_MEM >> res_tac >> fs []) >> simp [translate_label_def] >> rw [] >> rw [dest_label_def, num_calls_def] >> rw [translate_instrs_take_to_call] >> qmatch_goalsub_abbrev_tac `_ = HD (fst (translate_instrs a1 b1 c1 d1 e1))` >> Cases_on `translate_instrs a1 b1 c1 d1 e1` >> rw [] >> rename1 `_ = HD bl` >> Cases_on `bl` >> rw [] >- metis_tac [translate_instrs_not_empty, classify_instr_lem] >> rename1 `(_,_) = bl` >> Cases_on `bl` >> rw [] >> metis_tac [translate_instrs_first_lab]) >- metis_tac [get_instr_func, sum_distinct] >- metis_tac [get_instr_func, sum_distinct] >- ( (* TODO: LLVM "eval" gets stuck *) cheat) QED Theorem step_block_to_multi_step: ∀prog s1 s1' tr s2' b. state_rel prog gmap emap s1 s1' ∧ get_block (translate_prog prog) s1'.bp b ∧ step_block (translate_prog prog) s1' b.cmnd b.term tr s2' ⇒ ∃s2. multi_step prog s1 (map untranslate_trace tr) s2 ∧ state_rel prog gmap emap s2 s2' Proof (* TODO, LLVM can simulate llair direction *) cheat QED Theorem trans_trace_not_tau: ∀types. ($≠ Tau) ∘ translate_trace types = ($≠ Tau) Proof rw [FUN_EQ_THM] >> eq_tac >> rw [translate_trace_def] >> TRY (Cases_on `y`) >> fs [translate_trace_def] QED Theorem untrans_trace_not_tau: ∀types. ($≠ Tau) ∘ untranslate_trace = ($≠ Tau) Proof rw [FUN_EQ_THM] >> eq_tac >> rw [untranslate_trace_def] >> TRY (Cases_on `y`) >> fs [untranslate_trace_def] QED Theorem translate_prog_correct_lem1: ∀path. okpath (multi_step prog) path ∧ finite path ⇒ ∀emap s1'. prog_ok prog ∧ is_ssa prog ∧ dominator_ordered prog ∧ good_emap (first path).ip.f prog (get_regs_to_keep (THE (alookup prog (first path).ip.f))) (get_gmap prog) emap ∧ state_rel prog (get_gmap prog) emap (first path) s1' ∧ every (\(l, d). every (\(l, b). every is_implemented b.body) d.blocks) prog ⇒ ∃path'. finite path' ∧ okpath (step (translate_prog prog)) path' ∧ first path' = s1' ∧ LMAP (filter ($≠ Tau)) (labels path') = LMAP (map (translate_trace (get_gmap prog)) o filter ($≠ Tau)) (labels path) ∧ state_rel prog (get_gmap prog) emap (last path) (last path') Proof ho_match_mp_tac finite_okpath_ind >> rw [] >- (qexists_tac `stopped_at s1'` >> rw [] >> metis_tac []) >> fs [] >> rename1 `state_rel _ _ _ s1 s1'` >> Cases_on `s1.status ≠ Partial` >- fs [Once multi_step_cases, llvmTheory.step_cases, last_step_cases] >> fs [] >> drule multi_step_to_step_block >> simp [] >> rpt (disch_then drule) >> rw [] >> (* TODO: this won't be true once calls are added *) `s1.ip.f = (first path).ip.f` by cheat >> fs [] >> first_x_assum drule >> disch_then drule >> rw [] >> qexists_tac `pcons s1' tr' path'` >> rw [] >> rw [FILTER_MAP, combinTheory.o_DEF, trans_trace_not_tau] >> simp [step_cases] >> qexists_tac `b` >> simp [] >> qpat_x_assum `state_rel _ _ _ _ s1'` mp_tac >> rw [state_rel_def, mem_state_rel_def] QED Theorem translate_prog_correct_lem2: ∀path'. okpath (step (translate_prog prog)) path' ∧ finite path' ⇒ ∀s1. prog_ok prog ∧ state_rel prog gmap emap s1 (first path') ⇒ ∃path. finite path ∧ okpath (multi_step prog) path ∧ first path = s1 ∧ labels path = LMAP (map untranslate_trace) (labels path') ∧ state_rel prog gmap emap (last path) (last path') Proof ho_match_mp_tac finite_okpath_ind >> rw [] >- (qexists_tac `stopped_at s1` >> rw []) >> fs [step_cases] >> drule step_block_to_multi_step >> ntac 2 (disch_then drule) >> rw [] >> first_x_assum drule >> rw [] >> qexists_tac `pcons s1 (map untranslate_trace r) path` >> rw [] QED Theorem translate_global_var_11: ∀path. okpath (step (translate_prog prog)) path ∧ finite path ⇒ ∀x t1 bytes t2 l. labels path = fromList l ∧ MEM (W (Var_name x t1) bytes) (flat l) ∧ MEM (W (Var_name x t2) bytes) (flat l) ⇒ t1 = t2 Proof (* TODO, LLVM can simulate llair direction *) cheat QED Theorem prefix_take_filter_lemma: ∀l lsub. lsub ≼ l ⇒ filter (λy. Tau ≠ y) lsub = take (length (filter (λy. Tau ≠ y) lsub)) (filter (λy. Tau ≠ y) l) Proof Induct_on `lsub` >> rw [] >> Cases_on `l` >> fs [] >> rw [] QED Theorem multi_step_lab_label: ∀prog s1 ls s2. multi_step prog s1 ls s2 ⇒ s2.status ≠ Partial ⇒ ∃ls'. (∃i. ls = ls' ++ [Exit i]) ∨ ls = ls' ++ [Error] Proof ho_match_mp_tac multi_step_ind >> rw [] >> fs [] >> fs [last_step_cases, llvmTheory.step_cases, step_instr_cases, update_result_def, llvmTheory.inc_pc_def] >> rw [] >> fs [] QED Theorem prefix_filter_len_eq: ∀l1 l2 x. l1 ≼ l2 ++ [x] ∧ length (filter P l1) = length (filter P (l2 ++ [x])) ∧ P x ⇒ l1 = l2 ++ [x] Proof Induct_on `l1` >> rw [FILTER_APPEND] >> Cases_on `l2` >> fs [] >> rw [] >> rfs [ADD1] >> first_x_assum irule >> rw [FILTER_APPEND] QED Theorem translate_prog_correct: ∀prog s1 s1' emap. prog_ok prog ∧ is_ssa prog ∧ dominator_ordered prog ∧ good_emap s1.ip.f prog (get_regs_to_keep (THE (alookup prog s1.ip.f))) (get_gmap prog) emap ∧ state_rel prog (get_gmap prog) emap s1 s1' ∧ every (\(l, d). every (\(l, b). every is_implemented b.body) d.blocks) prog ⇒ multi_step_sem prog s1 = image (I ## map untranslate_trace) (sem (translate_prog prog) s1') Proof rw [sem_def, multi_step_sem_def, EXTENSION] >> eq_tac >> rw [] >- ( drule translate_prog_correct_lem1 >> simp [] >> rpt (disch_then drule) >> rw [EXISTS_PROD] >> PairCases_on `x` >> rw [] >> qexists_tac `map (translate_trace (get_gmap prog)) x1` >> rw [] >- rw [MAP_MAP_o, combinTheory.o_DEF, un_translate_trace_inv] >> qexists_tac `path'` >> rw [] >> fs [IN_DEF, observation_prefixes_cases, toList_some] >> rw [] >> `∃labs. labels path' = fromList labs` by ( fs [GSYM finite_labels] >> imp_res_tac llistTheory.LFINITE_toList >> fs [toList_some]) >> fs [] >> rfs [lmap_fromList, combinTheory.o_DEF, MAP_MAP_o] >> simp [FILTER_FLAT, MAP_FLAT, MAP_MAP_o, combinTheory.o_DEF, FILTER_MAP] >- fs [state_rel_def, mem_state_rel_def] >- fs [state_rel_def, mem_state_rel_def] >> rename [`labels path' = fromList l'`, `labels path = fromList l`, `state_rel _ _ _ (last path) (last path')`, `lsub ≼ flat l`] >> Cases_on `lsub = flat l` >> fs [] >- ( qexists_tac `flat l'` >> rw [FILTER_FLAT, MAP_FLAT, MAP_MAP_o, combinTheory.o_DEF] >> fs [state_rel_def, mem_state_rel_def]) >> `filter (λy. Tau ≠ y) (flat l') = map (translate_trace (get_gmap prog)) (filter (λy. Tau ≠ y) (flat l))` by rw [FILTER_FLAT, MAP_FLAT, MAP_MAP_o, combinTheory.o_DEF, FILTER_MAP] >> qexists_tac `take_prop ($≠ Tau) (length (filter ($≠ Tau) lsub)) (flat l')` >> rw [] >> rw [GSYM MAP_TAKE] >- metis_tac [prefix_take_filter_lemma] >> CCONTR_TAC >> fs [] >> `(last path).status = (last path').status` by fs [state_rel_def, mem_state_rel_def] >> drule take_prop_eq >> strip_tac >> `length (filter (λy. Tau ≠ y) (flat l')) = length (filter (λy. Tau ≠ y) (flat l))` by rw [] >> fs [] >> drule filter_is_prefix >> disch_then (qspec_then `$≠ Tau` assume_tac) >> drule IS_PREFIX_LENGTH >> strip_tac >> fs [] >> `length (filter (λy. Tau ≠ y) lsub) = length (filter (λy. Tau ≠ y) (flat l))` by rw [] >> fs [] >> rw [] >> qspec_then `path` assume_tac finite_path_end_cases >> rfs [] >> fs [] >> rw [] >- (`l = []` by metis_tac [llistTheory.fromList_EQ_LNIL] >> fs [] >> rfs []) >> rfs [labels_plink] >> rename1 `LAPPEND (labels path) [|last_l'|] = _` >> `toList (LAPPEND (labels path) [|last_l'|]) = Some l` by metis_tac [llistTheory.from_toList] >> drule llistTheory.toList_LAPPEND_APPEND >> strip_tac >> fs [llistTheory.toList_THM] >> rw [] >> drule multi_step_lab_label >> strip_tac >> rfs [] >> fs [] >> drule prefix_filter_len_eq >> rw [] >> qexists_tac `$≠ Tau` >> rw []) >- ( fs [toList_some] >> drule translate_prog_correct_lem2 >> simp [] >> disch_then drule >> rw [] >> qexists_tac `path'` >> rw [] >> fs [IN_DEF, observation_prefixes_cases, toList_some] >> rw [] >> rfs [lmap_fromList] >> simp [GSYM MAP_FLAT, FILTER_MAP, untrans_trace_not_tau] >- fs [state_rel_def, mem_state_rel_def] >- fs [state_rel_def, mem_state_rel_def] >> qexists_tac `map untranslate_trace l2'` >> simp [GSYM MAP_FLAT, FILTER_MAP, untrans_trace_not_tau] >> `INJ untranslate_trace (set l2' ∪ set (flat l2)) UNIV` by ( drule is_prefix_subset >> rw [SUBSET_DEF] >> `set l2' ∪ set (flat l2) = set (flat l2)` by (rw [EXTENSION] >> metis_tac []) >> simp [] >> simp [INJ_DEF] >> rpt gen_tac >> Cases_on `x` >> Cases_on `y` >> simp [untranslate_trace_def] >> Cases_on `a` >> Cases_on `a'` >> simp [untranslate_glob_var_def] >> metis_tac [translate_global_var_11]) >> fs [INJ_MAP_EQ_IFF, inj_map_prefix_iff] >> rw [] >> fs [state_rel_def, mem_state_rel_def]) QED export_theory ();