Source file rmciltmps.ml
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open GoblintCil
open Cilint
open Liveness
module E = Errormsg
module RD = Reachingdefs
module AELV = Availexpslv
module UD = Usedef
module IH = Inthash
module S = Stats
module IS =
Set.Make(struct
type t = int
let compare = Stdlib.compare
end)
let debug = RD.debug
let doTime = ref false
let time s f a =
if !doTime then
S.time s f a
else f a
type nameform = Suffix of string | Prefix of string | Exact of string
let getDefRhs = RD.getDefRhs
RD.ReachingDef.defIdStmtHash
RD.ReachingDef.stmtStartData
let exp_ok = ref true
class memReadOrAddrOfFinderClass = object(self)
inherit nopCilVisitor
method! vexpr e = match e with
Lval(Mem _, _) ->
exp_ok := false;
SkipChildren
| _ -> DoChildren
method! vvrbl vi =
if vi.vglob then
(if !debug then ignore(E.log "memReadOrAddrOfFinder: %s is a global\n"
vi.vname);
exp_ok := false;
SkipChildren)
else if vi.vaddrof then
(if !debug then
ignore(E.log "memReadOrAddrOfFinder: %s has its address taken\n"
vi.vname);
exp_ok := false;
SkipChildren)
else (if !debug then ignore(E.log "memReadOrAddrOfFinder: %s does not have its address taken\n"
vi.vname);
DoChildren)
end
let memReadOrAddrOfFinder = new memReadOrAddrOfFinderClass
let exp_is_ok_replacement e =
if !debug then ignore(E.log "exp_is_ok_replacement: in exp_is_ok_replacement with %a\n"
d_exp e);
exp_ok := true;
ignore(visitCilExpr memReadOrAddrOfFinder e);
!exp_ok
let emptyStmt = mkEmptyStmt ()
let fsr = ref emptyStmt
class stmtFinderClass sid = object(self)
inherit nopCilVisitor
method! vstmt stm =
if stm.sid = sid
then (fsr := stm; SkipChildren)
else DoChildren
end
let find_statement f sid = RD.getStmt sid
let wbHtbl = Hashtbl.create 256
let writes_between f dsid sid =
if Hashtbl.mem wbHtbl (dsid,sid) then Hashtbl.find wbHtbl (dsid,sid) else
let dstmo = find_statement f dsid in
let stmo = find_statement f sid in
let find_write s = match s.skind with
Instr il -> List.exists (fun i ->
match i with
Set((Mem _,_),_,_,_) -> true
| Set((_,Index (_,_)),_,_,_) -> true
| Call(_,_,_,_,_) -> true
| _ -> false) il
| _ -> false
in
let visited_sid_isr = ref IS.empty in
let rec dfs goal b start =
if !debug then ignore(E.log "writes_between: dfs visiting %a\n" d_stmt start);
if start.sid = goal.sid then
let wh = find_write start in
(if !debug && b then ignore(E.log "writes_between: start=goal and found a write\n");
if !debug && (not b) then ignore(E.log "writes_between: start=goal and no write\n");
if !debug && wh then ignore(E.log "writes_between: start=goal and write here\n");
if !debug && (not wh) then ignore(E.log "writes_between: start=goal and no write here\n");
b || (find_write start))
else
if IS.mem start.sid (!visited_sid_isr) then false else
let w = find_write start in
if !debug && w then ignore(E.log "writes_between: found write %a\n" d_stmt start);
visited_sid_isr := IS.add start.sid (!visited_sid_isr);
let rec proc_succs sl = match sl with [] -> false
| s::rest -> if dfs goal (w || b) s then true else proc_succs rest
in
proc_succs start.succs
in
match stmo, dstmo with
None, _ | _, None ->
E.s (E.error "writes_between: defining stmt not an instr")
| Some stm, Some dstm ->
let _ = visited_sid_isr := IS.singleton stm.sid in
let from_stm = List.fold_left (dfs stm) false stm.succs in
let _ = visited_sid_isr := IS.empty in
let from_dstm = dfs stm false dstm in
(Hashtbl.add wbHtbl (dsid,sid) (from_stm || from_dstm);
from_stm || from_dstm)
let verify_unmodified uses fdefs curiosh defiosh =
UD.VS.fold (fun vi b ->
let curido = RD.iosh_singleton_lookup curiosh vi in
let defido = RD.iosh_singleton_lookup defiosh vi in
match curido, defido with
Some(curid), Some(defid) ->
(if !debug then ignore (E.log "verify_unmodified: curido: %d defido: %d\n" curid defid);
curid = defid && b)
| None, None ->
if not(UD.VS.mem vi fdefs) then
(if !debug then ignore (E.log "verify_unmodified: %s not defined in function\n" vi.vname);
b)
else
let curios = try IH.find curiosh vi.vid
with Not_found -> RD.IOS.empty in
let defios = try IH.find defiosh vi.vid
with Not_found -> RD.IOS.empty in
RD.IOS.compare curios defios == 0 && b
| _, _ ->
(if !debug then ignore (E.log "verify_unmodified: %s has conflicting definitions. cur: %a\n def: %a\n"
vi.vname RD.ReachingDef.pretty ((),0,curiosh)
RD.ReachingDef.pretty ((),0,defiosh));
false))
uses true
let fdefs = ref UD.VS.empty
let udDeepSkindHtbl = IH.create 64
class defCollectorClass = object(self)
inherit nopCilVisitor
method! vstmt s =
let _,d = if IH.mem udDeepSkindHtbl s.sid
then IH.find udDeepSkindHtbl s.sid
else let u',d' = UD.computeDeepUseDefStmtKind s.skind in
IH.add udDeepSkindHtbl s.sid (u',d');
(u',d') in
fdefs := UD.VS.union !fdefs d;
DoChildren
end
let defCollector = new defCollectorClass
let collect_fun_defs fd =
fdefs := UD.VS.empty;
ignore(visitCilFunction defCollector fd);
!fdefs
let ok_to_replace vi curiosh sid defiosh dsid f r =
let uses, safe = match r with
RD.RDExp e -> (UD.computeUseExp e, exp_is_ok_replacement e)
| RD.RDCall (Call(_,_,el,_,_) as i) ->
let safe = List.fold_left (fun b e ->
(exp_is_ok_replacement e) && b) true el in
let u,d = UD.computeUseDefInstr i in
u, safe
| _ -> E.s (E.bug "ok_to_replace: got non Call in RDCall.")
in
let target_addrof = if vi.vaddrof || vi.vglob then
(if !debug then ignore(E.log "ok_to_replace: target %s had its address taken or is a global\n" vi.vname);
true)
else (if !debug then ignore(E.log "ok_to_replace: target %s does not have its address taken\n" vi.vname);
false) in
let writes = if safe && not(target_addrof) then false else (time "writes_between" (writes_between f dsid) sid) in
if (not safe || target_addrof) && writes
then
(if !debug then ignore (E.log "ok_to_replace: replacement not safe because of pointers or addrOf\n");
false)
else let fdefs = collect_fun_defs f in
let _ = if !debug then ignore (E.log "ok_to_replace: card fdefs = %d\n" (UD.VS.cardinal fdefs)) in
let _ = if !debug then ignore (E.log "ok_to_replace: card uses = %d\n" (UD.VS.cardinal uses)) in
verify_unmodified uses fdefs curiosh defiosh
let useList = ref []
class useListerClass (defid:int) (vi:varinfo) = object(self)
inherit RD.rdVisitorClass
method! vexpr e =
match e with
| Lval(Var vi', off) -> begin
match self#get_cur_iosh() with
Some iosh ->
let vido = RD.iosh_defId_find iosh defid in
let exists = match vido with Some _ -> true | None -> false in
if Util.equals vi vi' && exists
then (useList := sid::(!useList); DoChildren)
else DoChildren
| _ -> DoChildren
end
| _ -> DoChildren
end
let ok_to_replace_with_incdec curiosh defiosh f id vi r =
let num_uses () =
let _ = useList := [] in
let ulc = new useListerClass id vi in
let _ = visitCilFunction (ulc :> cilVisitor) f in
List.length (!useList)
in
let inc_or_dec e vi =
match e with
BinOp((PlusA|PlusPI|IndexPI), Lval(Var vi', NoOffset),
Const(CInt(a,_,_)),_) ->
if vi.vid = vi'.vid && compare_cilint a one_cilint = 0
then Some(PlusA)
else if vi.vid = vi'.vid && compare_cilint a mone_cilint = 0
then Some(MinusA)
else None
| BinOp((MinusA|MinusPI), Lval(Var vi', NoOffset),
Const(CInt(a,_,_)),_) ->
if vi.vid = vi'.vid && compare_cilint a one_cilint = 0
then Some(MinusA)
else None
| _ -> None
in
match r with
RD.RDExp(Lval(Var rhsvi, NoOffset)) ->
let curido = RD.iosh_singleton_lookup curiosh rhsvi in
let defido = RD.iosh_singleton_lookup defiosh rhsvi in
(match curido, defido with
Some(curid), _ ->
let defios = try IH.find defiosh rhsvi.vid
with Not_found -> RD.IOS.empty in
let redefrhso = getDefRhs curid in
(match redefrhso with
None -> (if !debug then ignore (E.log "ok_to_replace: couldn't get rhs for redef: %d\n" curid);
None)
| Some(redefrhs, _, redefiosh) ->
let tmprdido = RD.iosh_singleton_lookup redefiosh vi in
match tmprdido with
None -> (if !debug then ignore (E.log "ok_to_replace: conflicting defs of %s reach redef of %s\n" vi.vname rhsvi.vname);
None)
| Some tmprdid ->
if not (tmprdid = id) then
(if !debug then ignore (E.log "ok_to_replace: initial def of %s doesn't reach redef of %s\n" vi.vname rhsvi.vname);
None)
else let redefios = try IH.find redefiosh rhsvi.vid
with Not_found -> RD.IOS.empty in
let curdef_stmt = try IH.find RD.ReachingDef.defIdStmtHash curid
with Not_found -> E.s (E.error "ok_to_replace: couldn't find statement defining %d" curid) in
if not (RD.IOS.compare defios redefios = 0) then
(if !debug then ignore (E.log "ok_to_replace: different sets of definitions of %s reach the def of %s and the redef of %s\n"
rhsvi.vname vi.vname rhsvi.vname);
None)
else
(match redefrhs with
RD.RDExp(e) -> (match inc_or_dec e rhsvi with
Some(PlusA) ->
if num_uses () = 1 then
Some(curdef_stmt.sid, curid, rhsvi, PlusA)
else (if !debug then ignore (E.log "ok_to_replace: tmp used more than once\n");
None)
| Some(MinusA) ->
if num_uses () = 1 then
Some(curdef_stmt.sid, curid, rhsvi, MinusA)
else (if !debug then ignore (E.log "ok_to_replace: tmp used more than once\n");
None)
| None ->
(if !debug then ignore (E.log "ok_to_replace: redef isn't adding or subtracting one from itself\n");
None)
| _ -> E.s (E.error "ok_to_replace: unexpected op in inc/dec info."))
| _ -> (if !debug then ignore (E.log "ok_to_replace: redef a call\n");
None)))
| _ -> (if !debug then ignore (E.log "ok_to_replace: %s has conflicting definitions\n" rhsvi.vname);
None))
| _ -> (if !debug then ignore (E.log "ok_to_replace: rhs not of correct form\n");
None)
let iioh = IH.create 16
let incdecHash = IH.create 16
let idDefHash = IH.create 16
let id_dh_add vid p =
if IH.mem idDefHash vid then
let oldlist = IH.find idDefHash vid in
let newlist = p::oldlist in
IH.replace idDefHash vid newlist
else
IH.add idDefHash vid [p]
let check_form s f =
match f with
Suffix sfx ->
let frmlen = String.length sfx in
let slen = String.length s in
slen >= frmlen &&
compare (String.sub s (slen - frmlen) frmlen) sfx = 0
| Prefix pfx ->
let frmlen = String.length pfx in
String.length s >= frmlen &&
compare (String.sub s 0 frmlen) pfx = 0
| Exact ext ->
let frmlen = String.length ext in
String.length s = frmlen &&
compare s ext = 0
let check_forms s fl =
List.fold_left (fun b f -> b || check_form s f)
false fl
let forms = [Exact "tmp";
Prefix "tmp___";
Prefix "__cil_tmp";
Suffix "__e";
Suffix "__b";]
let varXformClass action data sid fd nofrm = object(self)
inherit nopCilVisitor
method! vexpr e = match e with
Lval(Var vi, NoOffset) ->
(match action data sid vi fd nofrm with
None -> DoChildren
| Some e' ->
let e'' = mkCast ~e:e' ~newt:vi.vtype in
ChangeTo e'')
| Lval(Mem e', off) ->
let post e = match e with
Lval(Mem(Const _),off') -> Lval(Mem e', off')
| _ -> e
in
ChangeDoChildrenPost(Lval(Mem e', off), post)
| _ -> DoChildren
end
let lvalXformClass action data sid fd nofrm = object(self)
inherit nopCilVisitor
method! vexpr e =
let castrm e = e
in
match e with
| Lval((Mem e', off) as lv)-> begin
match action data sid lv fd nofrm with
| None ->
let post e =
match e with
| Lval(Mem(Const _),off') -> Lval(Mem e', off')
| _ -> castrm e
in
ChangeDoChildrenPost(Lval(Mem e', off), post)
| Some e' ->
let e'' = mkCast ~e:e' ~newt:(typeOf(Lval lv)) in
ChangeDoChildrenPost(e'', castrm)
end
| Lval lv -> begin
match action data sid lv fd nofrm with
| None -> DoChildren
| Some e' -> begin
let e'' = mkCast ~e:e' ~newt:(typeOf(Lval lv)) in
ChangeDoChildrenPost(e'', castrm)
end
end
| e -> ChangeDoChildrenPost(castrm e, castrm)
end
let iosh_get_useful_def iosh vi =
if IH.mem iosh vi.vid then
let ios = IH.find iosh vi.vid in
let ios' = RD.IOS.filter (fun ido ->
match ido with None -> true | Some(id) ->
match time "getDefRhs" getDefRhs id with
Some(RD.RDExp(Lval(Var vi',NoOffset)),_,_)
| Some(RD.RDExp(CastE(_,Lval(Var vi',NoOffset))),_,_) ->
not(vi.vid = vi'.vid)
| _ -> true) ios
in
if not(RD.IOS.cardinal ios' = 1)
then (if !debug then ignore(E.log "iosh_get_useful_def: multiple different defs of %d:%s(%d)\n"
vi.vid vi.vname (RD.IOS.cardinal ios'));
None)
else RD.IOS.choose ios'
else (if !debug then ignore(E.log "iosh_get_useful_def: no def of %s reaches here\n" vi.vname);
None)
let ae_tmp_to_exp_change = ref false
let ae_tmp_to_exp eh sid vi fd nofrm =
if nofrm || (check_forms vi.vname forms)
then try begin
let e = IH.find eh vi.vid in
if !debug then ignore(E.log "tmp_to_exp: changing %s to %a\n"
vi.vname d_plainexp e);
match e with
| Const(CStr _)
| Const(CWStr _) -> None
| _ -> begin
ae_tmp_to_exp_change := true;
Some e
end
end
with Not_found -> None
else None
let ae_lval_to_exp_change = ref false
let ae_lval_to_exp ?(propStrings:bool = false) lvh sid lv fd nofrm =
match lv, nofrm with
| (Var vi, NoOffset), false ->
if check_forms vi.vname forms then begin
try
let e = AELV.LvExpHash.find lvh lv in
match e with
| Const(CStr _)
| Const(CWStr _) ->
if propStrings then (Some e) else None
| _ -> begin
ae_lval_to_exp_change := true;
if !debug then ignore(E.log "ae: replacing %a with %a\n"
d_lval lv d_exp e);
Some e
end
with Not_found -> None
end else None
| _, true -> begin
try
let e = AELV.LvExpHash.find lvh lv in
match e with
| Const(CStr _)
| Const(CWStr _) ->
if propStrings then (Some e) else None
| _ -> begin
ae_lval_to_exp_change := true;
if !debug then ignore(E.log "ae: replacing %a with %a\n"
d_lval lv d_exp e);
Some e
end
with Not_found -> None
end
| _, _ -> None
let rd_tmp_to_exp_change = ref false
let rd_tmp_to_exp iosh sid vi fd nofrm =
if nofrm || (check_forms vi.vname forms)
then let ido = iosh_get_useful_def iosh vi in
match ido with None ->
if !debug then ignore(E.log "tmp_to_exp: non-single def: %s\n" vi.vname);
None
| Some(id) -> let defrhs = time "getDefRhs" getDefRhs id in
match defrhs with None ->
if !debug then ignore(E.log "tmp_to_exp: no def of %s\n" vi.vname);
None
| Some(RD.RDExp(e) as r, dsid , defiosh) ->
if time "ok_to_replace" (ok_to_replace vi iosh sid defiosh dsid fd) r
then
(if !debug then ignore(E.log "tmp_to_exp: changing %s to %a\n" vi.vname d_plainexp e);
match e with
| Const(CStr _)
| Const(CWStr _) -> None
| _ -> begin
rd_tmp_to_exp_change := true;
Some e
end)
else
(if !debug then ignore(E.log "tmp_to_exp: not ok to replace %s\n" vi.vname);
None)
| _ ->
if !debug then ignore(E.log "tmp_to_exp: rhs is call %s\n" vi.vname);
None
else
(if !debug then ignore(E.log "tmp_to_exp: %s didn't match form or nofrm\n" vi.vname);
None)
let rd_fwd_subst data sid e fd nofrm =
rd_tmp_to_exp_change := false;
let e' = visitCilExpr (varXformClass rd_tmp_to_exp data sid fd nofrm) e in
(e', !rd_tmp_to_exp_change)
let ae_fwd_subst data sid e fd nofrm =
ae_tmp_to_exp_change := false;
let e' = visitCilExpr (varXformClass ae_tmp_to_exp data sid fd nofrm) e in
(e', !ae_tmp_to_exp_change)
let ae_lv_fwd_subst ?(propStrings:bool = false) data sid e fd nofrm =
ae_lval_to_exp_change := false;
let e' = visitCilExpr (lvalXformClass (ae_lval_to_exp ~propStrings:propStrings)
data sid fd nofrm) e
in
(e', !ae_lval_to_exp_change)
let ae_simp_fwd_subst data e nofrm =
ae_fwd_subst data (-1) e dummyFunDec nofrm
let ae_lv_simp_fwd_subst data e nofrm =
ae_lv_fwd_subst data (-1) e dummyFunDec nofrm
let ae_tmp_to_const_change = ref false
let ae_tmp_to_const eh sid vi fd nofrm =
if nofrm || check_forms vi.vname forms then
try begin let e = IH.find eh vi.vid in
match e with Const c -> begin
ae_tmp_to_const_change := true;
Some(Const c) end
| _ -> None end
with Not_found -> None
else None
let tmp_to_const_change = ref false
let tmp_to_const iosh sid vi fd nofrm =
if nofrm || check_forms vi.vname forms then
match RD.iosh_lookup iosh vi with
None -> None
| Some(ios) ->
let defido =
try RD.IOS.choose ios
with Not_found -> None in
match defido with None -> None | Some defid ->
match time "getDefRhs" getDefRhs defid with
None -> None
| Some(RD.RDExp(Const c), _, defiosh) ->
(match RD.getDefIdStmt defid with
None -> E.s (E.error "tmp_to_const: defid has no statement")
| Some(stm) -> if ok_to_replace vi iosh sid defiosh stm.sid fd (RD.RDExp(Const c)) then
let same = RD.IOS.for_all (fun defido ->
match defido with None -> false | Some defid ->
match time "getDefRhs" getDefRhs defid with
None -> false
| Some(RD.RDExp(Const c'),_,defiosh) ->
if Util.equals c c' then
match RD.getDefIdStmt defid with
None -> E.s (E.error "tmp_to_const: defid has no statement")
| Some(stm) -> ok_to_replace vi iosh sid defiosh stm.sid fd (RD.RDExp(Const c'))
else false
| _ -> false) ios
in
if same
then (tmp_to_const_change := true; Some(Const c))
else None
else None)
| _ -> None
else None
let const_prop iosh sid e fd nofrm =
tmp_to_const_change := false;
let e' = visitCilExpr (varXformClass tmp_to_const iosh sid fd nofrm) e in
(e', !tmp_to_const_change)
let ae_const_prop eh sid e fd nofrm =
ae_tmp_to_const_change := false;
let e' = visitCilExpr (varXformClass ae_tmp_to_const eh sid fd nofrm) e in
(e', !ae_tmp_to_const_change)
class expTempElimClass (fd:fundec) = object (self)
inherit RD.rdVisitorClass
method! vexpr e =
let do_change iosh vi =
let ido = RD.iosh_singleton_lookup iosh vi in
(match ido with
Some id ->
let riviho = getDefRhs id in
(match riviho with
Some(RD.RDExp(e) as r, dsid, defiosh) ->
if !debug then ignore(E.log "Can I replace %s with %a?\n" vi.vname d_exp e);
if ok_to_replace vi iosh sid defiosh dsid fd r
then
(if !debug then ignore(E.log "Yes.\n");
ChangeTo(e))
else (if !debug then ignore(E.log "No.\n");
DoChildren)
| _ -> DoChildren)
| _ -> DoChildren)
in
match e with
Lval (Var vi,NoOffset) ->
(if check_forms vi.vname forms then
(match cur_rd_dat with
Some(_,s,iosh) -> do_change iosh vi
| None -> let iviho = RD.getRDs sid in
match iviho with
Some(_,s,iosh) ->
(if !debug then ignore (E.log "Try to change %s outside of instruction.\n" vi.vname);
do_change iosh vi)
| None ->
(if !debug then ignore (E.log "%s in statement w/o RD info\n" vi.vname);
DoChildren))
else DoChildren)
| _ -> DoChildren
end
class expLvTmpElimClass (fd : fundec) = object(self)
inherit AELV.aeVisitorClass
method! vexpr e =
match self#get_cur_eh () with
| None -> DoChildren
| Some eh -> begin
let e', _ = ae_lv_fwd_subst ~propStrings:true eh sid e fd false in
ChangeTo e'
end
end
class incdecTempElimClass (fd:fundec) = object (self)
inherit RD.rdVisitorClass
method! vexpr e =
let do_change iosh vi =
let ido = RD.iosh_singleton_lookup iosh vi in
(match ido with
Some id ->
let riviho = getDefRhs id in
(match riviho with
Some(RD.RDExp(e) as r, _, defiosh) ->
(match ok_to_replace_with_incdec iosh defiosh fd id vi r with
Some(curdef_stmt_id,redefid, rhsvi, b) ->
(if !debug then ignore(E.log "No, but I can replace it with a post-inc/dec\n");
if !debug then ignore(E.log "cdsi: %d redefid: %d name: %s\n"
curdef_stmt_id redefid rhsvi.vname);
IH.add incdecHash vi.vid (redefid, rhsvi, b);
id_dh_add rhsvi.vid (curdef_stmt_id, redefid);
DoChildren)
| None ->
(if !debug then ignore(E.log "No.\n");
DoChildren))
| _ -> DoChildren)
| _ -> DoChildren)
in
match e with
Lval (Var vi,NoOffset) ->
(if check_forms vi.vname forms then
(match cur_rd_dat with
Some(_,s,iosh) -> do_change iosh vi
| None -> let iviho = RD.getRDs sid in
match iviho with
Some(_,s,iosh) ->
(if !debug then ignore (E.log "Try to change %s outside of instruction.\n" vi.vname);
do_change iosh vi)
| None ->
(if !debug then ignore (E.log "%s in statement w/o RD info\n" vi.vname);
DoChildren))
else DoChildren)
| _ -> DoChildren
end
class callTempElimClass (fd:fundec) = object (self)
inherit RD.rdVisitorClass
method! vexpr e =
let do_change iosh vi =
let ido = RD.iosh_singleton_lookup iosh vi in
(match ido with
Some id ->
let riviho = getDefRhs id in
(match riviho with
Some(RD.RDCall(i) as r, dsid, defiosh) ->
if !debug then ignore(E.log "Can I replace %s with %a?\n" vi.vname d_instr i);
if ok_to_replace vi iosh sid defiosh dsid fd r
then (if !debug then ignore(E.log "Yes.\n");
IH.add iioh vi.vid (Some(i));
DoChildren)
else (if !debug then ignore(E.log "No.\n");
DoChildren)
| _ -> DoChildren)
| _ -> DoChildren)
in
match e with
Lval (Var vi,NoOffset) ->
(if check_forms vi.vname forms then
if IH.mem iioh vi.vid
then (IH.replace iioh vi.vid None; DoChildren)
else
(match cur_rd_dat with
Some(_,s,iosh) -> do_change iosh vi
| None -> let iviho = RD.getRDs sid in
match iviho with
Some(_,s,iosh) ->
(if !debug then ignore (E.log "Try to change %s:%d outside of instruction.\n" vi.vname vi.vid);
do_change iosh vi)
| None ->
(if !debug then ignore (E.log "%s in statement w/o RD info\n" vi.vname);
DoChildren))
else DoChildren)
| _ -> DoChildren
method! vinst i =
if !debug then ignore(E.log "rdVis: before %a, rd_dat_lst is %d long\n"
d_instr i (List.length rd_dat_lst));
(try
cur_rd_dat <- Some(List.hd rd_dat_lst);
rd_dat_lst <- List.tl rd_dat_lst
with Failure _ ->
if !debug then ignore(E.log "rdVis: il rd_dat_lst mismatch\n"));
match i with
Set((Var vi,off),_,_,_) ->
if IH.mem iioh vi.vid
then (IH.replace iioh vi.vid None; DoChildren)
else (IH.add iioh vi.vid None; DoChildren)
| _ -> DoChildren
end
let rm_unused_locals fd =
let oldIgnoreSizeof = !UD.ignoreSizeof in
UD.ignoreSizeof := false;
let used = List.fold_left (fun u s ->
let u', d' = UD.computeDeepUseDefStmtKind s.skind in
UD.VS.union u (UD.VS.union u' d')) UD.VS.empty fd.sbody.bstmts in
UD.ignoreSizeof := oldIgnoreSizeof;
let good_var vi = UD.VS.mem vi used in
let good_locals = List.filter good_var fd.slocals in
fd.slocals <- good_locals
let is_volatile vi =
let vi_vol =
List.exists (function (Attr("volatile",_)) -> true
| _ -> false) vi.vattr in
let typ_vol =
List.exists (function (Attr("volatile",_)) -> true
| _ -> false) (typeAttrs vi.vtype) in
if !debug && (vi_vol || typ_vol) then
ignore(E.log "unusedRemover: %s is volatile\n" vi.vname);
if !debug && not(vi_vol || typ_vol) then
ignore(E.log "unusedRemover: %s is not volatile\n" vi.vname);
vi_vol || typ_vol
class unusedRemoverClass : cilVisitor = object(self)
inherit nopCilVisitor
val mutable unused_set = UD.VS.empty
val mutable cur_func = dummyFunDec
method! vfunc f =
cur_func <- f;
let used = List.fold_left (fun u s ->
let u', _ = UD.computeDeepUseDefStmtKind s.skind in
UD.VS.union u u') UD.VS.empty f.sbody.bstmts in
let used = UD.computeUseLocalTypes ~acc_used:used f in
let unused = List.fold_left (fun un vi ->
if UD.VS.mem vi used
then un
else (if !debug then ignore (E.log "unusedRemoverClass: %s is unused\n" vi.vname);
UD.VS.add vi un)) UD.VS.empty f.slocals in
let good_var vi =
(is_volatile vi) ||
(not(UD.VS.mem vi unused) &&
(not(IH.mem iioh vi.vid) ||
(match IH.find iioh vi.vid with
None -> true | Some _ -> false)) &&
not(IH.mem incdecHash vi.vid))
in
let good_locals = List.filter good_var f.slocals in
f.slocals <- good_locals;
unused_set <- unused;
DoChildren
method! vstmt stm =
let findf_in_pl f pl =
List.filter (fun (fst,snd) ->
if fst = f then true else false)
pl
in
let check_incdec vi e =
if IH.mem idDefHash vi.vid then
let pl = IH.find idDefHash vi.vid in
match findf_in_pl stm.sid pl with (sid,redefid)::l ->
let rhso = getDefRhs redefid in
(match rhso with
None -> (if !debug then ignore (E.log "check_incdec: couldn't find rhs for def %d\n" redefid);
false)
| Some(rhs, _, indiosh) ->
(match rhs with
RD.RDCall _ -> (if !debug then ignore (E.log "check_incdec: rhs not an expression\n");
false)
| RD.RDExp e' ->
if Util.equals e e' then true
else (if !debug then ignore (E.log "check_incdec: rhs of %d: %a, and needed redef %a not equal\n"
redefid d_plainexp e' d_plainexp e);
false)))
| [] -> (if !debug then ignore (E.log "check_incdec: current statement not in list: %d. %s = %a\n"
stm.sid vi.vname d_exp e);
false)
else (if !debug then ignore (E.log "check_incdec: %s not in idDefHash\n" vi.vname);
false)
in
let will_be_call e =
match e with
Lval(Var vi,NoOffset) ->
if not(IH.mem iioh vi.vid) then false
else (match IH.find iioh vi.vid with
None -> false | Some _ -> true)
| _ -> false
in
let good_instr i =
match i with
| Set((Var(vi),_),e,_,_) -> begin
if will_be_call e &&
not(List.mem vi cur_func.slocals) &&
not vi.vglob
then cur_func.slocals <- vi::cur_func.slocals;
is_volatile vi ||
(not (UD.VS.mem vi unused_set) &&
not (IH.mem incdecHash vi.vid) &&
not (check_incdec vi e)) ||
will_be_call e
end
| Call (Some(Var(vi),_),_,_,_,_) -> begin
not (IH.mem iioh vi.vid) ||
(match IH.find iioh vi.vid with
None -> true | Some _ -> false)
end
| Asm(_,_,slvlst,_,_,_) -> begin
List.iter (fun (_,s,lv) ->
match lv with (Var vi,_) ->
if List.mem vi cur_func.slocals
then ()
else cur_func.slocals <- vi::cur_func.slocals
|_ -> ()) slvlst;
true
end
| _ -> true
in
let call_fixer i =
match i with
Call (Some(Var(vi),_),e,el,l,eloc) as c ->
if UD.VS.mem vi unused_set then
Call(None,e,el,l,eloc)
else c
| _ -> i
in
match stm.skind with
Instr il ->
let newil = List.filter good_instr il in
let newil' = Util.list_map call_fixer newil in
stm.skind <- Instr(newil');
SkipChildren
| _ -> DoChildren
end
let rec fold_blocks b =
b.bstmts <- List.fold_right
(fun s acc ->
match s.skind with
Block ib ->
fold_blocks ib;
if (List.length ib.battrs = 0 &&
List.length s.labels = 0) then
ib.bstmts @ acc
else
s::acc
| Instr il when il = [] && s.labels = [] ->
acc
| _ -> s::acc)
b.bstmts
[]
class removeBrackets = object (self)
inherit nopCilVisitor
method! vblock b =
fold_blocks b;
DoChildren
end
let eliminate_temps f =
ignore(visitCilFunction (new removeBrackets) f);
Cfg.clearCFGinfo f;
ignore(Cfg.cfgFun f);
UD.ignoreSizeof := false;
RD.computeRDs f;
IH.clear iioh;
IH.clear incdecHash;
IH.clear idDefHash;
let etec = new expLvTmpElimClass f in
let f' = visitCilFunction (etec :> cilVisitor) f in
RD.clearMemos ();
let idtec = new incdecTempElimClass f' in
let f' = visitCilFunction (idtec :> cilVisitor) f' in
let ctec = new callTempElimClass f' in
let f' = visitCilFunction (ctec :> cilVisitor) f' in
let f' = visitCilFunction (new unusedRemoverClass) f' in
f'
let eliminateTempsForExpPrinting f =
Cfg.clearCFGinfo f;
ignore(Cfg.cfgFun f);
UD.ignoreSizeof := false;
RD.computeRDs f;
IH.clear iioh;
IH.clear incdecHash;
IH.clear idDefHash;
let etec = new expLvTmpElimClass f in
let f' = visitCilFunction (etec :> cilVisitor) f in
RD.clearMemos ();
let idtec = new incdecTempElimClass f' in
let f' = visitCilFunction (idtec :> cilVisitor) f' in
let ctec = new callTempElimClass f' in
let f' = visitCilFunction (ctec :> cilVisitor) f' in
f'