direct addressing in comparison

git-svn-id: http://caml.inria.fr/svn/ocaml/branches/newoolab@6098 f963ae5c-01c2-4b8c-9fe0-0dff7051ff02

7 files changed, 54 insertions, 0 deletions

diff --git a/asmcomp/i386/arch.ml b/asmcomp/i386/arch.ml
index bcbfb5f3f7..802d74ca28 100644
--- a/asmcomp/i386/arch.ml
+++ b/asmcomp/i386/arch.ml
@@ -48,6 +48,9 @@ type specific_operation =
                                         (* bool: true=64 bits, false=32 *)
   | Ifloatspecial of string
 
+and 'a specific_test =
+    Iinttests of 'a * bool * addressing_mode
+
 and float_operation =
     Ifloatadd | Ifloatsub | Ifloatsubrev | Ifloatmul | Ifloatdiv | Ifloatdivrev
 
@@ -78,6 +81,10 @@ let num_args_addressing = function
   | Iscaled(scale, n) -> 1
   | Iindexed2scaled(scale, n) -> 2
 
+let invert_specific_test negate = function
+    Iinttests (cmp, sgn, addr) ->
+      Iinttests (negate cmp, sgn, addr)
+
 (* Printing operations and addressing modes *)
 
 let print_addressing printreg addr ppf arg =
@@ -145,3 +152,12 @@ let print_specific_operation printreg op ppf arg =
         printreg ppf arg.(i)
       done
       
+let print_specific_test printreg printcmp tst ppf arg =
+  match tst with
+    Iinttests (cmp, sgn, addr) ->
+      fprintf ppf "%a %s%c %a"
+        printreg (arg.(0))
+        (printcmp cmp)
+        (if sgn then 'c' else 'u')
+        (print_addressing printreg addr)
+        (Array.sub arg 1 (Array.length arg - 1))
diff --git a/asmcomp/i386/emit.mlp b/asmcomp/i386/emit.mlp
index 17c0362f3e..0bdd992970 100644
--- a/asmcomp/i386/emit.mlp
+++ b/asmcomp/i386/emit.mlp
@@ -695,6 +695,12 @@ let emit_instr fallthrough i =
             `	cmpl	{emit_reg i.arg.(1)}, {emit_reg i.arg.(0)}\n`;
             let b = name_for_cond_branch cmp in
             `	j{emit_string b}	{emit_label lbl}\n`
+        | Ispectest (Iinttests (cmp, sgn, addr)) ->
+            `	cmpl	{emit_addressing addr i.arg 1}, {emit_reg i.arg.(0)}\n`;
+            let cmp = if sgn then Isigned cmp else Iunsigned cmp in
+            let b = name_for_cond_branch cmp in
+            `	j{emit_string b}	{emit_label lbl}\n`
+            
         | Iinttest_imm((Isigned Ceq | Isigned Cne | 
                         Iunsigned Ceq | Iunsigned Cne) as cmp, 0) ->
             output_test_zero i.arg.(0);
diff --git a/asmcomp/i386/selection.ml b/asmcomp/i386/selection.ml
index 621cb8de38..03c2c45ea4 100644
--- a/asmcomp/i386/selection.ml
+++ b/asmcomp/i386/selection.ml
@@ -260,6 +260,32 @@ method select_floatarith regular_op reversed_op mem_op mem_rev_op args =
   | _ ->
       fatal_error "Proc_i386: select_floatarith"
 
+(* Recognize direct addressing in comparisons *)
+method select_condition = function
+    Cop ((Ccmpi cmp | Ccmpa cmp as op), [arg1; arg2]) as exp ->
+      (* Format.printf "%a@." Printcmm.expression exp; *)
+      let sgn = (op = Ccmpi cmp) in
+      let make_test cmp addr arg arg1 =
+        match arg1 with
+          Cconst_int _ | Cconst_pointer _ -> super#select_condition exp
+        | _ -> (Ispectest(Iinttests(cmp, sgn, addr)), Ctuple [arg1; arg])
+      in
+      let get_addressing = function
+          Cop (Cload Word, [arg]) -> self#select_addressing arg
+        | _ -> (Iindexed 0, Ctuple[])
+      in
+      begin match get_addressing arg1 with
+        (Iindexed 0, _) ->
+          begin match get_addressing arg2 with
+            (Iindexed 0, _) -> super#select_condition exp
+          | (addr, arg)     -> make_test cmp addr arg arg1
+          end
+      | (addr, arg) ->
+          make_test (Cmm.swap_comparison cmp) addr arg arg2
+      end
+  | exp ->
+      super#select_condition exp
+
 (* Deal with register constraints *)
 
 method insert_op op rs rd =
diff --git a/asmcomp/linearize.ml b/asmcomp/linearize.ml
index 506f5a11c3..dbc7344280 100644
--- a/asmcomp/linearize.ml
+++ b/asmcomp/linearize.ml
@@ -69,6 +69,8 @@ let invert_test = function
   | Ifloattest(cmp, neg) -> Ifloattest(cmp, not neg)
   | Ieventest -> Ioddtest
   | Ioddtest -> Ieventest
+  | Ispectest tst ->
+      Ispectest (Arch.invert_specific_test Cmm.negate_comparison tst)
 
 (* The "end" instruction *)
 
diff --git a/asmcomp/mach.ml b/asmcomp/mach.ml
index 6417b5c40e..3458bcde58 100644
--- a/asmcomp/mach.ml
+++ b/asmcomp/mach.ml
@@ -32,6 +32,7 @@ type test =
   | Ifloattest of Cmm.comparison * bool
   | Ioddtest
   | Ieventest
+  | Ispectest of Cmm.comparison Arch.specific_test
 
 type operation =
     Imove
diff --git a/asmcomp/mach.mli b/asmcomp/mach.mli
index ec10ffb814..4804096cfe 100644
--- a/asmcomp/mach.mli
+++ b/asmcomp/mach.mli
@@ -32,6 +32,7 @@ type test =
   | Ifloattest of Cmm.comparison * bool
   | Ioddtest
   | Ieventest
+  | Ispectest of Cmm.comparison Arch.specific_test
 
 type operation =
     Imove
diff --git a/asmcomp/printmach.ml b/asmcomp/printmach.ml
index 17cf675b98..ba23b51a50 100644
--- a/asmcomp/printmach.ml
+++ b/asmcomp/printmach.ml
@@ -95,6 +95,8 @@ let test tst ppf arg =
        reg arg.(0) (floatcomp cmp) reg arg.(1)
   | Ieventest -> fprintf ppf "%a & 1 == 0" reg arg.(0)
   | Ioddtest -> fprintf ppf "%a & 1 == 1" reg arg.(0)
+  | Ispectest tst ->
+      Arch.print_specific_test reg Printcmm.comparison tst ppf arg
 
 let print_live = ref false