(* * 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 *) 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; new_theory "llvm_to_llair_prop"; set_grammar_ancestry ["llvm", "llair", "llair_prop", "llvm_to_llair", "llvm_ssa"]; 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 Definition dest_llair_lab_def: dest_llair_lab (Lab_name f b) = (f, b) End Definition build_phi_block_def: build_phi_block gmap emap f entry from_l to_l phis = generate_move_block [(to_l, (translate_header (dest_fn f) gmap emap entry (Head phis ARB), (ARB:block)))] (translate_label_opt (dest_fn f) entry from_l) to_l End Definition build_phi_emap_def: build_phi_emap phis = map (\x. case x of Phi r t _ => (r, Var (translate_reg r t))) phis End Inductive pc_rel: (* LLVM side points to a normal instruction *) (∀prog emap ip bp d b idx b' prev_i fname gmap. (* Both are valid pointers to blocks in the same function *) dest_fn ip.f = fst (dest_llair_lab 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 *) (ip.i ≠ Offset 0 ⇒ get_instr prog (ip with i := Offset (idx - 1)) (Inl prev_i) ∧ is_call prev_i) ∧ ip.f = Fn fname ∧ (∃regs_to_keep. b' = fst (translate_instrs fname gmap emap regs_to_keep (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 bp from_l phis entry to_l. get_instr prog ip (Inr (from_l, phis)) ∧ (* 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 (build_phi_block gmap emap ip.f entry from_l to_l phis) ∧ pc_rel prog gmap (emap |++ build_phi_emap phis) (ip with i := inc_bip ip.i) to_l ⇒ pc_rel prog gmap emap ip bp) End Definition untranslate_reg_def: untranslate_reg (Var_name x t) = Reg x 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 ip locals locals' r = ∃v v' e. v_rel v.value v' ∧ flookup locals r = Some v ∧ flookup emap r = Some e ∧ eval_exp <| locals := locals' |> e v' ∧ (* Each register used in e is dominated by an assignment to that * register for the entire live range of r. *) (∀ip1 r'. ip1.f = ip.f ∧ r ∈ live prog ip1 ∧ r' ∈ exp_uses e ⇒ ∃ip2. untranslate_reg r' ∈ assigns prog ip2 ∧ dominates prog ip2 ip1) End Definition local_state_rel_def: local_state_rel prog emap ip locals locals' ⇔ (* Live LLVM registers are mapped and have a related value in the emap * (after evaluating) *) (∀r. r ∈ live prog ip ⇒ emap_invariant prog emap ip locals locals' r) End Definition mem_state_rel_def: mem_state_rel prog gmap emap (s:llvm$state) (s':llair$state) ⇔ local_state_rel prog emap s.ip s.locals s'.locals ∧ reachable prog s.ip ∧ fmap_rel (\(_,n) n'. w2n n = n') s.globals (s'.glob_addrs f_o translate_glob_var gmap) ∧ 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$state) with status := Complete code).locals = s.locals Proof rw [] QED Theorem mem_state_rel_exited: ∀prog gmap emap s s' code. mem_state_rel prog gmap emap s s' ⇒ mem_state_rel prog gmap emap (s with status := Complete code) (s' with status := Complete code) Proof rw [mem_state_rel_def, local_state_rel_def, emap_invariant_def] >> metis_tac [eval_exp_ignores, lemma] QED Theorem mem_state_rel_no_update: ∀prog gmap emap s1 s1' v res_v r i i'. assigns prog s1.ip = {} ∧ mem_state_rel prog gmap emap s1 s1' ∧ i ∈ next_ips prog s1.ip ⇒ mem_state_rel prog gmap emap (s1 with ip := i) s1' Proof rw [mem_state_rel_def, local_state_rel_def, emap_invariant_def] >- ( first_x_assum (qspec_then `r` mp_tac) >> simp [Once live_gen_kill, PULL_EXISTS] >> metis_tac [next_ips_same_func]) >- metis_tac [next_ips_reachable] QED Triviality record_lemma: (<|locals := x|> :llair$state).locals = x Proof rw [] QED Theorem mem_state_rel_update: ∀prog gmap emap s1 s1' v res_v r e i. is_ssa prog ∧ assigns prog s1.ip = {r} ∧ mem_state_rel prog gmap emap s1 s1' ∧ eval_exp s1' e res_v ∧ v_rel v.value res_v ∧ i ∈ next_ips prog s1.ip ∧ (∀r_use. r_use ∈ exp_uses e ⇒ ∃r_tmp. r_use ∈ exp_uses (translate_arg gmap emap (Variable r_tmp)) ∧ r_tmp ∈ live prog s1.ip) ⇒ mem_state_rel prog gmap (emap |+ (r, e)) (s1 with <|ip := i; locals := s1.locals |+ (r, v) |>) s1' Proof rw [mem_state_rel_def, local_state_rel_def, emap_invariant_def] >- ( rw [FLOOKUP_UPDATE] >- ( HINT_EXISTS_TAC >> rw [] >- metis_tac [eval_exp_ignores, record_lemma] >> first_x_assum drule >> rw [] >> first_x_assum drule >> rw [] >> fs [exp_uses_def, translate_arg_def] >> pop_assum (qspec_then `s1.ip` mp_tac) >> simp [] >> disch_then drule >> rw [] >> `dominates prog s1.ip ip1` by ( irule ssa_dominates_live_range_lem >> rw [] >> metis_tac [next_ips_same_func]) >> metis_tac [dominates_trans]) >> `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)``] >> metis_tac []) >- metis_tac [next_ips_reachable] QED Theorem emap_inv_updates_keep_same_ip1: ∀prog emap ip locals locals' vs res_vs rtys r. is_ssa prog ∧ list_rel v_rel (map (\v. v.value) vs) res_vs ∧ length rtys = length vs ∧ r ∈ set (map fst rtys) ⇒ emap_invariant prog (emap |++ map (\(r,ty). (r, Var (translate_reg r ty))) rtys) ip (locals |++ zip (map fst rtys, vs)) (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]) >> CASE_TAC >> rw [] >- ( fs [ALOOKUP_NONE, MAP_REVERSE, MAP_MAP_o, combinTheory.o_DEF] >> fs [MEM_MAP, FORALL_PROD] >> rw [] >> metis_tac [FST, pair_CASES]) >> rename [`alookup (reverse (zip _)) _ = Some v`, `alookup (reverse (map _ _)) _ = Some e`] >> fs [Once MEM_SPLIT_APPEND_last] >> fs [alookup_some, MAP_EQ_APPEND, reverse_eq_append] >> rw [] >> rfs [zip_eq_append] >> rw [] >> rw [] >> rename [`(fst rty, e)::reverse res = map _ rtys`] >> Cases_on `rtys` >> fs [] >> pairarg_tac >> fs [] >> 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 [] >> rfs [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] >> `(\(x:reg,y:ty). x) = fst` by (rw [FUN_EQ_THM] >> pairarg_tac >> rw []) >> fs [] >> rename [`map fst l1 ++ [fst _] ++ map fst l2 = l3 ++ [_] ++ l4`, `map _ l1 ++ [translate_reg _ _] ++ _ = l5 ++ _ ++ l6`, `l7 ++ [v1:llair$flat_v reg_v] ++ l8 = l9 ++ [v2] ++ l10`] >> `map fst l2 = l4` by metis_tac [append_split_last] >> `~mem (translate_reg (fst rty) ty) (map (λ(r,ty). translate_reg r ty) l2)` by ( rw [MEM_MAP] >> pairarg_tac >> fs [] >> Cases_on `rty` >> rename1 `fst (r2, ty2)` >> Cases_on `r2` >> Cases_on `r` >> fs [translate_reg_def, MEM_MAP] >> metis_tac [FST]) >> `map (λ(r,ty). translate_reg r ty) l2 = l6` by metis_tac [append_split_last] >> `length l8 = length l10` by metis_tac [LIST_REL_LENGTH, LENGTH_MAP] >> metis_tac [append_split_eq]) >- ( fs [exp_uses_def] >> rw [] >> Cases_on `fst rty` >> simp [translate_reg_def, untranslate_reg_def] >> `∃ip. ip.f = ip1.f ∧ Reg s ∈ uses prog ip` by ( qabbrev_tac `x = (ip1.f = ip.f)` >> fs [live_def] >> qexists_tac `last (ip1::path)` >> rw [] >> irule good_path_same_func >> qexists_tac `ip1::path` >> rw [MEM_LAST] >> metis_tac []) >> metis_tac [ssa_dominates_live_range]) QED Theorem emap_inv_updates_keep_same_ip2: ∀prog emap ip locals locals' vs res_vs rtys r. is_ssa prog ∧ r ∈ live prog ip ∧ assigns prog ip = set (map fst rtys) ∧ emap_invariant prog emap ip locals locals' r ∧ list_rel v_rel (map (\v. v.value) vs) res_vs ∧ length rtys = length vs ∧ reachable prog ip ∧ ¬mem r (map fst rtys) ⇒ emap_invariant prog (emap |++ map (\(r,ty). (r, Var (translate_reg r ty))) rtys) ip (locals |++ zip (map fst rtys, vs)) (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 [] >- ( CASE_TAC >> rw [] >- ( qexists_tac `v'` >> rw [] >> `DRESTRICT (locals' |++ zip (map (λ(r,ty). translate_reg r ty) rtys, res_vs)) (exp_uses e) = DRESTRICT locals' (exp_uses e)` suffices_by metis_tac [eval_exp_ignores_unused, record_lemma] >> rw [] >> 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 _` >> first_x_assum (qspecl_then [`ip`, `translate_reg r1 ty1`] mp_tac) >> rw [] >> CCONTR_TAC >> fs [] >> `ip2 = ip` by ( fs [is_ssa_def, EXTENSION, IN_DEF] >> Cases_on `r1` >> fs [translate_reg_def, untranslate_reg_def] >> `assigns prog ip (Reg s)` suffices_by metis_tac [reachable_dominates_same_func] >> rw [LIST_TO_SET_MAP, MEM_EL] >> metis_tac [FST]) >> metis_tac [dominates_irrefl]) >> drule ALOOKUP_MEM >> rw [MEM_MAP] >> pairarg_tac >> fs [MEM_MAP] >> rw [] >> metis_tac [FST]) >> 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 ip1 ip2 locals locals'. local_state_rel prog emap ip1 locals locals' ∧ ip2 ∈ next_ips prog ip1 ∧ (∀r. r ∈ assigns prog ip1 ⇒ emap_invariant prog emap ip1 locals locals' r) ⇒ local_state_rel prog emap ip2 locals locals' Proof rw [local_state_rel_def, emap_invariant_def] >> Cases_on `r ∈ live prog ip1` >> fs [] >- ( last_x_assum drule >> rw [] >> ntac 3 HINT_EXISTS_TAC >> rw [] >> first_x_assum irule >> rw [] >> metis_tac [next_ips_same_func]) >> 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 ip locals locals' vs res_vs i. is_ssa prog ∧ set (map fst rtys) = assigns prog ip ∧ local_state_rel prog emap ip locals locals' ∧ length vs = length rtys ∧ list_rel v_rel (map (\v. v.value) vs) res_vs ∧ i ∈ next_ips prog ip ∧ reachable prog ip ⇒ local_state_rel prog (emap |++ map (\(r,ty). (r, Var (translate_reg r ty))) rtys) i (locals |++ zip (map fst rtys, vs)) (locals' |++ zip (map (\(r,ty). translate_reg r ty) rtys, res_vs)) Proof rw [] >> irule local_state_rel_next_ip >> qexists_tac `ip` >> rw [] >> fs [local_state_rel_def] >> rw [] >- (irule emap_inv_updates_keep_same_ip1 >> rw []) >> fs [local_state_rel_def] >> rw [] >> Cases_on `mem r (map fst rtys)` >- (irule emap_inv_updates_keep_same_ip1 >> rw []) >> irule emap_inv_updates_keep_same_ip2 >> rw [] QED Theorem local_state_rel_update_keep: ∀prog emap ip locals locals' v res_v r i ty. is_ssa prog ∧ assigns prog ip = {r} ∧ local_state_rel prog emap ip locals locals' ∧ v_rel v.value res_v ∧ reachable prog ip ∧ i ∈ next_ips prog ip ⇒ local_state_rel prog (emap |+ (r, Var (translate_reg r ty))) i (locals |+ (r, v)) (locals' |+ (translate_reg r ty, res_v)) Proof rw [] >> drule local_state_rel_updates_keep >> disch_then (qspecl_then [`[(r,ty)]`, `emap`, `ip`] 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. is_ssa prog ∧ assigns prog s.ip = {r} ∧ 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 |+ (r, Var (translate_reg r ty))) (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] >- metis_tac [local_state_rel_update_keep] >> metis_tac [next_ips_reachable] QED Triviality lemma: ((s:llair$state) with heap := h).locals = s.locals Proof rw [] QED Theorem mem_state_rel_heap_update: ∀prog gmap emap s s' h h'. mem_state_rel prog gmap emap s s' ∧ heap_ok h ∧ erase_tags h = erase_tags h' ⇒ mem_state_rel prog gmap emap (s with heap := h) (s' with heap := h') Proof rw [mem_state_rel_def, erase_tags_def, local_state_rel_def] >> rw [heap_component_equality] >> fs [fmap_eq_flookup, FLOOKUP_o_f] >> rw [] >> first_x_assum (qspec_then `x` mp_tac) >> BasicProvers.EVERY_CASE_TAC >> rw [] >> Cases_on `x'` >> Cases_on `x''` >> fs [] QED Theorem v_rel_bytes: ∀v v'. v_rel v v' ⇒ llvm_value_to_bytes v = llair_value_to_bytes v' Proof ho_match_mp_tac v_rel_ind >> rw [v_rel_cases, llvm_value_to_bytes_def, llair_value_to_bytes_def] >> rw [value_to_bytes_def, llvmTheory.unconvert_value_def, w2n_i2n, llairTheory.unconvert_value_def, llairTheory.pointer_size_def, llvmTheory.pointer_size_def] >> pop_assum mp_tac >> qid_spec_tac `vs1` >> Induct_on `vs2` >> rw [] >> rw [] QED Theorem bytes_v_rel_lem: (∀f s bs t. f = (λn t w. convert_value t w) ∧ s = type_to_shape t ∧ first_class_type t ⇒ (quotient_pair$### 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 Theorem translate_constant_correct_lem: (∀c s prog gmap emap s'. mem_state_rel prog gmap emap s s' ⇒ ∃v'. eval_exp s' (translate_const gmap c) v' ∧ v_rel (eval_const s.globals c) v') ∧ (∀(cs : (ty # const) list) s prog gmap emap s'. mem_state_rel prog gmap emap s s' ⇒ ∃v'. list_rel (eval_exp s') (map (translate_const gmap o snd) cs) v' ∧ list_rel v_rel (map (eval_const s.globals o snd) cs) v') ∧ (∀(tc : ty # const) s prog gmap emap s'. mem_state_rel prog gmap emap s s' ⇒ ∃v'. eval_exp s' (translate_const gmap (snd tc)) v' ∧ v_rel (eval_const s.globals (snd tc)) v') Proof ho_match_mp_tac const_induction >> rw [translate_const_def] >> simp [Once eval_exp_cases, eval_const_def] >- ( Cases_on `s` >> simp [eval_const_def, translate_size_def, v_rel_cases] >> metis_tac [truncate_2comp_i2w_w2i, dimindex_1, dimindex_8, dimindex_32, dimindex_64]) >- ( simp [v_rel_cases, PULL_EXISTS, MAP_MAP_o] >> fs [combinTheory.o_DEF, LAMBDA_PROD] >> metis_tac []) >- ( simp [v_rel_cases, PULL_EXISTS, MAP_MAP_o] >> fs [combinTheory.o_DEF, LAMBDA_PROD] >> metis_tac []) (* TODO: unimplemented stuff *) >- cheat >- ( fs [mem_state_rel_def, fmap_rel_OPTREL_FLOOKUP] >> CASE_TAC >> fs [] >> first_x_assum (qspec_then `g` mp_tac) >> rw [] >> rename1 `option_rel _ _ opt` >> Cases_on `opt` >> fs [OPTREL_def] >> (* TODO: false at the moment, need to work out the llair story on globals *) cheat) (* TODO: unimplemented stuff *) >- cheat >- cheat QED Theorem translate_constant_correct: ∀c s prog gmap emap s' g. mem_state_rel prog gmap emap s s' ⇒ ∃v'. eval_exp s' (translate_const gmap c) v' ∧ v_rel (eval_const s.globals c) v' Proof metis_tac [translate_constant_correct_lem] QED (* TODO: This isn't true, since the translation turns LLVM globals into llair * locals *) 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 []) >- cheat >- cheat QED Theorem translate_arg_correct: ∀s a v prog gmap emap s'. mem_state_rel prog gmap emap s s' ∧ eval s a = Some 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_def, 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, record_lemma] 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 ns result. mem_state_rel prog gmap emap s1 s1' ∧ map (λci. signed_v_to_num (eval_const s1.globals ci)) cs = 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 [] >> fs [extract_value_def] >- metis_tac [] >> first_x_assum irule >> Cases_on `ns` >> fs [] >> qmatch_goalsub_rename_tac `translate_const gmap c` >> `?v2'. eval_exp s1' (translate_const gmap c) v2' ∧ v_rel (eval_const s1.globals c) 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 `eval_const s1.globals c` >> 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 ns result. mem_state_rel prog gmap emap s1 s1' ∧ map (λci. signed_v_to_num (eval_const s1.globals ci)) cs = 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 [] >> 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 [] >> `?v4'. eval_exp s1' (translate_const gmap c) v4' ∧ v_rel (eval_const s1.globals c) 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 (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 trunc_thms = LIST_CONJ (map (fn x => SIMP_RULE (srw_ss()) [] (INST_TYPE [``:'a`` |-> x] truncate_2comp_i2w_w2i)) [``:1``, ``:8``, ``:32``, ``:64``]); val i2n_thms = LIST_CONJ (map (fn x => SIMP_RULE (srw_ss()) [] (INST_TYPE [``:'a`` |-> x] (GSYM w2n_i2n))) [``:1``, ``:8``, ``:32``, ``:64``]); Theorem translate_cast_correct: ∀prog gmap emap s1' cop ty v1 v1' e1' result t2. do_cast cop v1.value ty = Some result ∧ eval_exp s1' e1' v1' ∧ v_rel v1.value v1' ∧ (cop = Inttoptr ⇒ ∃t. ty = PtrT t) ⇒ ∃v3'. eval_exp s1' (Convert (cop ≠ Sext) (translate_ty ty) t2 e1') v3' ∧ v_rel result v3' Proof rw [] >> simp [Once eval_exp_cases, PULL_EXISTS, Once v_rel_cases] >> Cases_on `cop ≠ Sext` >- ( Cases_on `cop` >> fs [do_cast_def] >> rw [] >> BasicProvers.EVERY_CASE_TAC >> fs [] >> fs [OPTION_JOIN_EQ_SOME, w64_cast_some, signed_v_to_int_some, unsigned_v_to_num_some, mk_ptr_some] >> rw [sizeof_bits_def, translate_ty_def, translate_size_def] >> rfs [] >> fs [v_rel_cases] >> HINT_EXISTS_TAC >> rw [w2w_n2w, trunc_thms, i2n_thms, w2w_def, pointer_size_def]) >> fs [do_cast_def, OPTION_JOIN_EQ_SOME, PULL_EXISTS, w64_cast_some, translate_ty_def, sizeof_bits_def, signed_v_to_int_some, translate_size_def] >> rfs [v_rel_cases, w2w_i2w] >> rw [trunc_thms] >> qmatch_assum_abbrev_tac `eval_exp _ _ (FlatV (IntV i s))` >> qexists_tac `s` >> qexists_tac `i` >> rw [] >> unabbrev_all_tac >> rw [] >> rw [i2w_w2i_extend, WORD_w2w_OVER_MUL, WORD_ALL_BITS] >> Cases_on `w2w w : word1` >> rw [] >> fs [dimword_1] >> Cases_on `n` >> rw [] >> fs [] >> Cases_on `n'` >> rw [] >> fs [] QED Theorem prog_ok_nonterm: ∀prog i ip. prog_ok prog ∧ get_instr prog ip (Inl i) ∧ ¬terminator i ⇒ inc_pc ip ∈ next_ips prog ip Proof rw [next_ips_cases, IN_DEF, get_instr_cases, PULL_EXISTS] >> `terminator (last b.body) ∧ b.body ≠ []` by metis_tac [prog_ok_def] >> Cases_on `length b.body = idx + 1` >- ( drule LAST_EL >> rw [] >> fs [DECIDE ``PRE (x + 1) = x``]) >> Cases_on `el idx b.body` >> fs [instr_next_ips_def, terminator_def] >> rw [EXISTS_OR_THM, inc_pc_def, inc_bip_def] 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 [translate_const_no_reg, 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 [translate_const_no_reg, 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. is_ssa prog ∧ prog_ok prog ∧ 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 ⇒ ∃pv emap' s2'. l = Tau ∧ s2.ip = inc_pc s1.ip ∧ mem_state_rel prog gmap emap' s2 s2' ∧ (r ∉ regs_to_keep ⇒ s1' = s2' ∧ emap' = emap |+ (r, translate_instr_to_exp gmap emap instr)) ∧ (r ∈ regs_to_keep ⇒ emap' = emap |+ (r,Var (translate_reg r t)) ∧ 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}` 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 []) >- ( irule mem_state_rel_update >> rw [] >- ( fs [exp_uses_def] >| [Cases_on `a1`, Cases_on `a2`] >> fs [translate_arg_def] >> rename1 `flookup _ r_tmp` >> qexists_tac `r_tmp` >> rw [] >> simp [Once live_gen_kill] >> disj2_tac >> simp [uses_cases, IN_DEF, get_instr_cases, instr_uses_def, arg_to_regs_def]) >> 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}` 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 []) >- ( irule mem_state_rel_update >> rw [] >- ( Cases_on `a` >> fs [translate_arg_def] >> rename1 `flookup _ r_tmp` >> qexists_tac `r_tmp` >> rw [] >> simp [Once live_gen_kill] >> disj2_tac >> simp [uses_cases, IN_DEF, get_instr_cases, instr_uses_def, arg_to_regs_def]) >> 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 >> first_x_assum (mp_then.mp_then mp_then.Any mp_tac translate_arg_correct) >> 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}` 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 []) >- ( irule mem_state_rel_update >> strip_tac >- ( Cases_on `a1` >> Cases_on `a2` >> rw [translate_arg_def] >> rename1 `flookup _ r_tmp` >> qexists_tac `r_tmp` >> rw [] >> simp [Once live_gen_kill] >> disj2_tac >> simp [uses_cases, IN_DEF, get_instr_cases, instr_uses_def, arg_to_regs_def]) >> rw [] >> metis_tac [] ))>> conj_tac >- ( (* Cast *) rw [step_instr_cases, get_instr_cases, update_result_def] >> 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 >> rw [] >> drule translate_cast_correct >> ntac 2 (disch_then drule) >> simp [] >> disch_then (qspec_then `translate_ty t1` mp_tac) >> impl_tac (* TODO: prog_ok should enforce that the type is consistent *) >- cheat >> rw [] >> rename1 `eval_exp _ (Convert _ _ _ _) res_v` >> rw [inc_pc_def, llvmTheory.inc_pc_def] >> rename1 `r ∈ _` >> `assigns prog s1.ip = {r}` 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 []) >- ( irule mem_state_rel_update >> rw [] >- ( fs [exp_uses_def] >> Cases_on `a1` >> fs [translate_arg_def] >> rename1 `flookup _ r_tmp` >> qexists_tac `r_tmp` >> rw [] >> simp [Once live_gen_kill] >> disj2_tac >> simp [uses_cases, IN_DEF, get_instr_cases, instr_uses_def, arg_to_regs_def]) >> metis_tac [])) >> (* TODO: unimplemented instruction translations *) cheat 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. classify_instr instr = Non_exp ∧ prog_ok prog ∧ is_ssa prog ∧ 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 (extend_emap_non_exp emap instr) 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])) >- 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 []) >- ( (* TODO: mem_state_rel needs to relate the globals *) fs [get_obs_cases, llvmTheory.get_obs_cases] >> rw [translate_trace_def] >> fs [mem_state_rel_def, fmap_rel_OPTREL_FLOOKUP] >- ( first_x_assum (qspec_then `x` mp_tac) >> rw [] >> rename1 `option_rel _ _ opt` >> Cases_on `opt` >> fs [OPTREL_def] >> cheat) >> cheat)) QED Theorem classify_instr_term_call: ∀i. (classify_instr i = Term ⇔ terminator i) ∧ (classify_instr i = Call ⇔ is_call 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 [] >> first_x_assum drule >> simp [ADD1] QED Theorem translate_instrs_correct1: ∀prog s1 tr s2. multi_step prog s1 tr s2 ⇒ ∀s1' b' gmap emap regs_to_keep d b idx. prog_ok prog ∧ is_ssa prog ∧ mem_state_rel prog gmap emap s1 s1' ∧ alookup prog s1.ip.f = Some d ∧ alookup d.blocks s1.ip.b = Some b ∧ s1.ip.i = Offset idx ∧ b' = fst (translate_instrs (dest_fn s1.ip.f) gmap emap regs_to_keep (take_to_call (drop idx b.body))) ⇒ ∃emap 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 *) `(∃code. l = Exit code) ∨ l = Tau ` by ( fs [llvmTheory.step_cases] >> `i' = i''` 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 `emap` >> qexists_tac `s1' with status := Complete code` >> qexists_tac `[Exit code]` >> rw [] >- (fs [v_rel_cases] >> fs [signed_v_to_int_def] >> metis_tac []) >> rw [state_rel_def] >> metis_tac [mem_state_rel_exited]) >> simp [take_to_call_def, translate_instrs_def] >> Cases_on `el idx b.body` >> fs [terminator_def, classify_instr_def, translate_trace_def] >> rw [] >- ( (* Ret *) cheat) >- ( (* Br *) simp [translate_instr_to_term_def, Once step_block_cases] >> simp [step_term_cases, PULL_EXISTS, RIGHT_AND_OVER_OR, EXISTS_OR_THM] >> 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] >> qexists_tac `emap` >> qexists_tac `w2i tf` >> simp [] >> conj_tac >- metis_tac [] >> Cases_on `s1'.bp` >> fs [dest_llair_lab_def] >> rename1 `el _ _ = Br e lab1 lab2` >> qexists_tac `dest_fn s1.ip.f` >> qexists_tac `if 0 = w2i tf then dest_label lab2 else dest_label lab1` >> simp [] >> qpat_abbrev_tac `target = if tf = 0w then l2 else l1` >> qpat_abbrev_tac `target' = if 0 = w2i tf then dest_label lab2 else dest_label lab1` >> `last b.body = Br a 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])) >> rw [] >> `translate_label (dest_fn s1.ip.f) target = Lab_name (dest_fn s1.ip.f) target' ` by ( fs [get_instr_cases] >> rw [] >> unabbrev_all_tac >> rw [] >> fs [word_0_w2i] >> Cases_on `l2` >> Cases_on `l1` >> rw [translate_label_def, dest_label_def] >> `0 = w2i (0w:word1)` by rw [word_0_w2i] >> fs [w2i_11]) >> rw [state_rel_def] >- (Cases_on `lab2` >> rw [Abbr `target'`, translate_label_def, dest_label_def]) >- (Cases_on `lab1` >> rw [Abbr `target'`, translate_label_def, dest_label_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] >> fs [translate_prog_def] >> `∀y z. dest_fn y = dest_fn z ⇒ y = z` by (Cases_on `y` >> Cases_on `z` >> rw [dest_fn_def]) >> rw [alookup_map_key] >> (* TODO *) cheat) >- ( 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 []))) >- ( (* Invoke *) cheat) >- ( (* Unreachable *) cheat) >- ( (* Exit *) fs [llvmTheory.step_cases, get_instr_cases, step_instr_cases]) >- ( (* Throw *) cheat)) >- ( (* Call *) cheat) >- ( (* 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 [] >- ( (* instructions that compile to expressions *) drule translate_instr_to_exp_correct >> ntac 5 (disch_then drule) >> disch_then (qspec_then `regs_to_keep` mp_tac) >> 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 (qspecl_then [`regs_to_keep`] mp_tac) >> rw [] >> rename1 `state_rel prog gmap emap3 s3 s3'` >> qexists_tac `emap3` >> qexists_tac `s3'` >> rw [] >> `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]) >> simp [translate_instrs_def] >> Cases_on `r ∉ regs_to_keep` >> fs [] >> rw [] >- metis_tac [] >> qexists_tac `Tau::tr'` >> rw [] >> simp [Once step_block_cases] >> disj2_tac >> pairarg_tac >> rw [] >> fs [] >> metis_tac []) >- ( (* Non-expression instructions *) Cases_on `classify_instr i` >> fs [classify_instr_term_call] >> drule translate_instr_to_inst_correct >> ntac 5 (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 >> rename1 `state_rel prog gmap emap3 s3 s3'` >> qexists_tac `emap3` >> qexists_tac `s3'` >> simp [] >> `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]) >> simp [translate_instrs_def] >> qexists_tac `translate_trace gmap l::tr'` >> rw [] >> simp [Once step_block_cases] >> pairarg_tac >> rw [] >> fs [] >> disj2_tac >> qexists_tac `s2'` >> rw [])) QED Theorem do_phi_vals: ∀prog gmap emap from_l s s' phis updates. mem_state_rel prog gmap emap s s' ∧ map (do_phi from_l s) phis = map Some 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 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 [] >> Cases_on `updates` >> fs [] >> first_x_assum drule >> disch_then drule >> rw [] >> Cases_on `h` >> fs [do_phi_def, OPTION_JOIN_EQ_SOME] >> drule translate_arg_correct >> disch_then drule >> impl_tac >- (fs [phi_uses_def] >> rfs []) >> rw [PULL_EXISTS, phi_assigns_def] >> metis_tac [] QED Triviality dest_phi_trip: ∀p f. (λ(x,y,z). f x y z) (dest_phi p) = (λx. case x of Phi x y z => f x y z) p Proof Cases >> rw [dest_phi_def] 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 Triviality map_fst_map2: ∀l1 l2 f g. length l1 = length l2 ⇒ map fst (map2 (λp e. case p of Phi r t largs => (f r t largs, g e)) l1 l2) = map (λp. case p of Phi r t largs => f r t largs) l1 Proof Induct_on `l1` >> rw [] >> Cases_on `l2` >> fs [] >> CASE_TAC >> rw [] QED Theorem build_phi_block_correct: ∀prog s1 s1' to_l from_l phis updates f gmap emap entry bloc. prog_ok prog ∧ is_ssa prog ∧ get_instr prog s1.ip (Inr (from_l,phis)) ∧ map (do_phi from_l s1) phis = map Some updates ∧ mem_state_rel prog gmap emap s1 s1' ∧ BIGUNION (set (map (phi_uses from_l) phis)) ⊆ live prog s1.ip ∧ bloc = build_phi_block gmap emap f entry from_l to_l phis ⇒ ?s2'. s2'.bp = to_l ∧ step_block (translate_prog prog) s1' bloc.cmnd bloc.term [Tau; Tau] s2' ∧ mem_state_rel prog gmap (emap |++ build_phi_emap phis) (inc_pc (s1 with locals := s1.locals |++ updates)) s2' Proof rw [build_phi_block_def, 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] >> simp [MAP_MAP_o, combinTheory.o_DEF, PULL_EXISTS, dest_phi_trip] >> simp [case_phi_lift, build_move_for_lab_def] >> (* TODO: This is false because of how the entry block label is translated. * Needs fixing. *) `∀l1 l2. translate_label_opt (dest_fn f) entry l1 = translate_label_opt (dest_fn f) entry l2 ⇒ l1 = l2` by cheat >> qspecl_then [`l`, `from_l`, `translate_label_opt (dest_fn f) entry`, `\x arg. translate_arg gmap emap arg`] (mp_tac o Q.GEN `l`) alookup_map_key >> simp [] >> disch_then kall_tac >> drule do_phi_vals >> ntac 2 (disch_then drule) >> rw [] >> rw [] >> pop_assum kall_tac >> simp [step_inst_cases, PULL_EXISTS] >> qexists_tac `0` >> qexists_tac `vs` >> rw [] >- ( simp [LIST_REL_MAP1] >> fs [LIST_REL_EL_EQN, EL_MAP2] >> rw [MIN_DEF] >- metis_tac [LENGTH_MAP, DECIDE ``(x:num) = y ⇒ ~(x < y)``] >> CASE_TAC >> simp []) >> simp [llvmTheory.inc_pc_def, update_results_def, MAP_ID, id2] >> `length phis = length es` by metis_tac [LENGTH_MAP, LIST_REL_LENGTH] >> rw [map_fst_map2] >> `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 [] >- ( `map fst (map (λx. case x of Phi r t v2 => (r,t)) phis) = map phi_assigns phis` by (rw [LIST_EQ_REWRITE, EL_MAP] >> CASE_TAC >> rw [phi_assigns_def]) >> 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 [] >- ( rw [assigns_cases, EXTENSION, IN_DEF] >> metis_tac [get_instr_func, sum_distinct, INR_11, PAIR_EQ]) >- metis_tac [LENGTH_MAP] >- rw [MAP_MAP_o, combinTheory.o_DEF] >> fs [MAP_MAP_o, combinTheory.o_DEF, case_phi_lift] >> `updates = zip (map fst updates,map snd updates)` suffices_by metis_tac [build_phi_emap_def] >> rw [ZIP_MAP] >> rw [LIST_EQ_REWRITE, EL_MAP]) >- (irule next_ips_reachable >> qexists_tac `s1.ip` >> rw []) QED Theorem multi_step_to_step_block: ∀prog gmap emap s1 tr s2 s1'. prog_ok prog ∧ is_ssa prog ∧ multi_step prog s1 tr s2 ∧ s1.status = Partial ∧ state_rel prog gmap emap s1 s1' ⇒ ∃s2' emap2 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 gmap) tr) ∧ state_rel prog gmap emap2 s2 s2' Proof rw [] >> 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 (qspecl_then [`regs_to_keep`] mp_tac) >> simp [] >> rw [] >> qexists_tac `s2'` >> simp [] >> ntac 3 HINT_EXISTS_TAC >> rw [] >> fs [dest_fn_def]) >> (* 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 [] >> qmatch_assum_abbrev_tac `get_block _ _ bloc` >> GEN_EXISTS_TAC "b" `bloc` >> drule build_phi_block_correct >> ntac 2 (disch_then drule) >> simp [Abbr `bloc`] >> disch_then (qspecl_then [`s1'`, `to_l`, `updates`, `s1.ip.f`, `gmap`, `emap`, `entry`] 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'` >> qexists_tac `emap |++ build_phi_emap phis` >> qexists_tac `[Tau; Tau]` >> rw [] >> fs [state_rel_def] >> rw [] >> fs [llvmTheory.inc_pc_def]) >- metis_tac [get_instr_func, sum_distinct] >- metis_tac [get_instr_func, sum_distinct] >- ( fs [llvmTheory.step_cases] >> rw [translate_trace_def] >> `!i. ¬get_instr prog s1.ip (Inl i)` by metis_tac [get_instr_func, sum_distinct] >> fs [METIS_PROVE [] ``~x ∨ y ⇔ (x ⇒ y)``] >> first_x_assum drule >> rw [] >> `¬every IS_SOME (map (do_phi from_l s1) phis)` by metis_tac [map_is_some] >> fs [get_instr_cases] >> rename [`alookup _ s1.ip.b = Some b_targ`, `alookup _ from_l = Some b_src`] >> `every (phi_contains_label from_l) phis` by ( fs [prog_ok_def, get_instr_cases] >> first_x_assum (qspecl_then [`s1.ip.f`, `d`, `from_l`] mp_tac) >> rw [] >> fs [EVERY_MEM, MEM_MAP] >> rfs [] >> rw [] >> first_x_assum drule >> rw [] >> first_x_assum irule >> fs [] >> rfs [] >> fs []) >> fs [EVERY_MEM, EXISTS_MEM, MEM_MAP] >> first_x_assum drule >> rw [] >> rename1 `phi_contains_label _ phi` >> Cases_on `phi` >> fs [do_phi_def, phi_contains_label_def] >> rename1 `alookup entries from_l ≠ None` >> Cases_on `alookup entries from_l` >> fs [] >> (* 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 = ($≠ Tau) Proof rw [FUN_EQ_THM] >> eq_tac >> rw [untranslate_trace_def] >> TRY (Cases_on `y`) >> fs [untranslate_trace_def] QED Theorem translate_prog_correct_lem1: ∀path. okpath (multi_step prog) path ∧ finite path ⇒ ∀gmap emap s1'. prog_ok prog ∧ is_ssa prog ∧ state_rel prog gmap emap (first path) s1' ⇒ ∃path' emap. finite path' ∧ okpath (step (translate_prog prog)) path' ∧ first path' = s1' ∧ LMAP (filter ($≠ Tau)) (labels path') = LMAP (map (translate_trace gmap) o filter ($≠ Tau)) (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 [] >> 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 >> ntac 4 (disch_then drule) >> rw [] >> first_x_assum drule >> rw [] >> qexists_tac `pcons s1' tr' path'` >> rw [] >> rw [FILTER_MAP, combinTheory.o_DEF, trans_trace_not_tau] >> HINT_EXISTS_TAC >> simp [] >> 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'. prog_ok prog ∧ is_ssa prog ∧ state_rel prog gmap emap s1 s1' ⇒ 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 >> ntac 4 (disch_then drule) >> rw [EXISTS_PROD] >> PairCases_on `x` >> rw [] >> qexists_tac `map (translate_trace gmap) 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 gmap) (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 ();