(* *********************************************************************)
(*                                                                     *)
(*              The Compcert verified compiler                         *)
(*                                                                     *)
(*          Xavier Leroy, INRIA Paris-Rocquencourt                     *)
(*                                                                     *)
(*  Copyright Institut National de Recherche en Informatique et en     *)
(*  Automatique.  All rights reserved.  This file is distributed       *)
(*  under the terms of the INRIA Non-Commercial License Agreement.     *)
(*                                                                     *)
(* *********************************************************************)
(** The whole compiler and its proof of semantic preservation *)
(** Libraries. *)
(** Languages (syntax and semantics). *)
Require Ctypes Csyntax Csem Cstrategy Cexec.
Require Clight.
Require Csharpminor.
Require Cminor.
Require CminorSel.
Require RTL.
Require LTL.
Require Linear.
Require Mach.
Require Asm.
(** Translation passes. *)
Require Initializers.
Require SimplExpr.
Require SimplLocals.
Require Cshmgen.
Require Cminorgen.
Require Selection.
Require RTLgen.
Require Tailcall.
Require Inlining.
Require Renumber.
Require Constprop.
Require CSE.
Require Deadcode.
Require Unusedglob.
Require Allocation.
Require Tunneling.
Require Linearize.
Require CleanupLabels.
Require Debugvar.
Require Stacking.
Require Asmgen.
(** Proofs of semantic preservation. *)
Require SimplExprproof.
Require SimplLocalsproof.
Require Cshmgenproof.
Require Cminorgenproof.
Require Selectionproof.
Require RTLgenproof.
Require Tailcallproof.
Require Inliningproof.
Require Renumberproof.
Require Constpropproof.
Require CSEproof.
Require Deadcodeproof.
Require Unusedglobproof.
Require Allocproof.
Require Tunnelingproof.
Require Linearizeproof.
Require CleanupLabelsproof.
Require Debugvarproof.
Require Stackingproof.
Require Asmgenproof.
(** Command-line flags. *)
(** Pretty-printers (defined in Caml). *)
Parameter print_Clight: Clight.program -> unit.
Parameter print_Cminor: Cminor.program -> unit.
Parameter print_RTL: Z -> RTL.program -> unit.
Parameter print_LTL: LTL.program -> unit.
Parameter print_Mach: Mach.program -> unit.
Local Open Scope string_scope.
(** * Composing the translation passes *)
(** We first define useful monadic composition operators, along with funny (but convenient) notations. *)
Definition apply_total (A B: Type) (x: res A) (f: A -> B) : res B :=
match x with Error msg => Error msg | OK x1 => OK (f x1) end.
Definition apply_partial (A B: Type)
(x: res A) (f: A -> res B) : res B :=
match x with Error msg => Error msg | OK x1 => f x1 end.
Notation "a @@@ b" :=
(apply_partial _ _ a b) (at level 50, left associativity).
Notation "a @@ b" :=
(apply_total _ _ a b) (at level 50, left associativity).
Definition print {A: Type} (printer: A -> unit) (prog: A) : A :=
let unused := printer prog in prog.
Definition time {A B: Type} (name: string) (f: A -> B) : A -> B := f.
Definition total_if {A: Type}
(flag: unit -> bool) (f: A -> A) (prog: A) : A :=
if flag tt then f prog else prog.
Definition partial_if {A: Type}
(flag: unit -> bool) (f: A -> res A) (prog: A) : res A :=
if flag tt then f prog else OK prog.
(** We define three translation functions for whole programs: one starting with a C program, one with a Cminor program, one with an RTL program.  The three translations produce Asm programs ready for pretty-printing and assembling. *)
Definition transf_rtl_program (f: RTL.program) : res Asm.program :=
OK f
@@ print (print_RTL 0)
@@ total_if Compopts.optim_tailcalls (time "Tail calls" Tailcall.transf_program)
@@ print (print_RTL 1)
@@@ time "Inlining" Inlining.transf_program
@@ print (print_RTL 2)
@@ time "Renumbering" Renumber.transf_program
@@ print (print_RTL 3)
@@ total_if Compopts.optim_constprop (time "Constant propagation" Constprop.transf_program)
@@ print (print_RTL 4)
@@ total_if Compopts.optim_constprop (time "Renumbering" Renumber.transf_program)
@@ print (print_RTL 5)
@@@ partial_if Compopts.optim_CSE (time "CSE" CSE.transf_program)
@@ print (print_RTL 6)
@@@ partial_if Compopts.optim_redundancy (time "Redundancy elimination" Deadcode.transf_program)
@@ print (print_RTL 7)
@@@ time "Unused globals" Unusedglob.transform_program
@@ print (print_RTL 8)
@@@ time "Register allocation" Allocation.transf_program
@@ print print_LTL
@@ time "Branch tunneling" Tunneling.tunnel_program
@@@ time "CFG linearization" Linearize.transf_program
@@ time "Label cleanup" CleanupLabels.transf_program
@@@ partial_if Compopts.debug (time "Debugging info for local variables" Debugvar.transf_program)
@@@ time "Mach generation" Stacking.transf_program
@@ print print_Mach
@@@ time "Asm generation" Asmgen.transf_program.
Definition transf_cminor_program (p: Cminor.program) : res Asm.program :=
OK p
@@ print print_Cminor
@@@ time "Instruction selection" Selection.sel_program
@@@ time "RTL generation" RTLgen.transl_program
@@@ transf_rtl_program.
Definition transf_clight_program (p: Clight.program) : res Asm.program :=
OK p
@@ print print_Clight
@@@ time "Simplification of locals" SimplLocals.transf_program
@@@ time "C#minor generation" Cshmgen.transl_program
@@@ time "Cminor generation" Cminorgen.transl_program
@@@ transf_cminor_program.
Definition transf_c_program (p: Csyntax.program) : res Asm.program :=
OK p
@@@ time "Clight generation" SimplExpr.transl_program
@@@ transf_clight_program.
(** Force [Initializers] and [Cexec] to be extracted as well. *)
Definition transl_init := Initializers.transl_init.
Definition cexec_do_step := Cexec.do_step.
(** The following lemmas help reason over compositions of passes. *)
(** * Relational specification of compilation *)
Definition match_if {A: Type} (flag: unit -> bool) (R: A -> A -> Prop): A -> A -> Prop :=
if flag tt then R else eq.

Lemma partial_if_match:
forall (A: Type) (flag: unit -> bool) (f: A -> res A) (rel: A -> A -> Prop) (prog tprog: A),
(forall p tp, f p = OK tp -> rel p tp) ->
partial_if flag f prog = OK tprog ->
match_if flag rel prog tprog.