kill useless moves (not yet connected)

1 files changed, 40 insertions, 0 deletions

diff --git a/backend/KillUselessMoves.v b/backend/KillUselessMoves.v
new file mode 100644
index 00000000..bdd7ec60
--- /dev/null
+++ b/backend/KillUselessMoves.v
@@ -0,0 +1,40 @@
+(* *************************************************************)
+(*                                                             *)
+(*             The Compcert verified compiler                  *)
+(*                                                             *)
+(*           David Monniaux     CNRS, VERIMAG                  *)
+(*                                                             *)
+(*  Copyright VERIMAG. All rights reserved.                    *)
+(*  This file is distributed under the terms of the INRIA      *)
+(*  Non-Commercial License Agreement.                          *)
+(*                                                             *)
+(* *************************************************************)
+
+Require Import Coqlib Maps Errors Integers Floats Lattice Kildall.
+Require Import AST Linking.
+Require Import Memory Registers Op RTL.
+Require List.
+
+Definition transf_ros (ros: reg + ident) : reg + ident := ros.
+
+Definition transf_instr (pc: node) (instr: instruction) :=
+  match instr with
+  | Iop op args res s =>
+    if (eq_operation op Omove) && (List.list_eq_dec peq args (res :: nil))
+    then Inop s
+    else instr
+  | _ => instr
+  end.
+
+Definition transf_function (f: function) : function :=
+  {| fn_sig := f.(fn_sig);
+     fn_params := f.(fn_params);
+     fn_stacksize := f.(fn_stacksize);
+     fn_code := PTree.map transf_instr f.(fn_code);
+     fn_entrypoint := f.(fn_entrypoint) |}.
+
+Definition transf_fundef (fd: fundef) : fundef :=
+  AST.transf_fundef transf_function fd.
+
+Definition transf_program (p: program) : program :=
+  transform_program transf_fundef p.