Fix mcode for i386 Darwin.

5 files changed, 100 insertions, 48 deletions

diff --git a/ortho/mcode/ortho_code-exprs.adb b/ortho/mcode/ortho_code-exprs.adb
index a98facf45..ecab78283 100644
--- a/ortho/mcode/ortho_code-exprs.adb
+++ b/ortho/mcode/ortho_code-exprs.adb
@@ -181,6 +181,11 @@ package body Ortho_Code.Exprs is
       return O_Dnode (Enodes.Table (Enode).Arg1);
    end Get_Call_Subprg;
 
+   function Get_Stack_Adjust (Enode : O_Enode) return Int32 is
+   begin
+      return Int32 (Enodes.Table (Enode).Arg1);
+   end Get_Stack_Adjust;
+
    function Get_Arg_Link (Enode : O_Enode) return O_Enode is
    begin
       return Enodes.Table (Enode).Arg2;
@@ -1231,7 +1236,7 @@ package body Ortho_Code.Exprs is
 
       New_Enode_Stmt (OE_Ret, Get_Type_Mode (V_Type), Value, O_Enode_Null);
       if not Flag_Debug_Hli then
-         Emit_Jmp (OE_Jump, O_Enode_Null, Cur_Subprg.Exit_Label);
+         New_Allocb_Jump (Cur_Subprg.Exit_Label);
       end if;
    end New_Return_Stmt;
 
@@ -1244,7 +1249,7 @@ package body Ortho_Code.Exprs is
       end if;
 
       if not Flag_Debug_Hli then
-         Emit_Jmp (OE_Jump, O_Enode_Null, Cur_Subprg.Exit_Label);
+         New_Allocb_Jump (Cur_Subprg.Exit_Label);
       else
          New_Enode_Stmt (OE_Ret, Mode_Nil, O_Enode_Null, O_Enode_Null);
       end if;
diff --git a/ortho/mcode/ortho_code-exprs.ads b/ortho/mcode/ortho_code-exprs.ads
index 5c7da6199..9bd4596d7 100644
--- a/ortho/mcode/ortho_code-exprs.ads
+++ b/ortho/mcode/ortho_code-exprs.ads
@@ -111,11 +111,14 @@ package Ortho_Code.Exprs is
       --  ARG1 is subprogram
       --  ARG2 is arguments.
       OE_Call,
-      --  ARG1 is the subprogram.
-      OE_Setup_Frame,
       --  ARG1 is intrinsic operation.
       OE_Intrinsic,
 
+      --  Modify the stack pointer value, to align the stack before pushing
+      --  arguments, or to free the stack.
+      --  ARG1 is the signed offset.
+      OE_Stack_Adjust,
+
       --  Return ARG1 (if not mode_nil) from current subprogram.
       --  ARG1: expression.
       OE_Ret,
@@ -326,6 +329,12 @@ package Ortho_Code.Exprs is
    function Get_Addrl_Frame (Enode : O_Enode) return O_Enode;
    procedure Set_Addrl_Frame (Enode : O_Enode; Frame : O_Enode);
 
+   --  Return the stack adjustment. For positive values, this is the amount of
+   --  bytes to allocate on the stack before pushing arguments, so that the
+   --  stack pointer stays aligned. For negtive values, this is the amount of
+   --  bytes to release on the stack.
+   function Get_Stack_Adjust (Enode : O_Enode) return Int32;
+
    --  Get the subprogram called by ENODE.
    function Get_Call_Subprg (Enode : O_Enode) return O_Dnode;
 
diff --git a/ortho/mcode/ortho_code-x86-abi.adb b/ortho/mcode/ortho_code-x86-abi.adb
index a915f9235..99b75e945 100644
--- a/ortho/mcode/ortho_code-x86-abi.adb
+++ b/ortho/mcode/ortho_code-x86-abi.adb
@@ -463,6 +463,10 @@ package body Ortho_Code.X86.Abi is
             end if;
             Disp_Decl_Name (Get_Call_Subprg (Stmt));
             New_Line;
+         when OE_Stack_Adjust =>
+            Put ("  stack_adjust: ");
+            Put (Int32'Image (Get_Stack_Adjust (Stmt)));
+            New_Line;
          when OE_Intrinsic =>
             Disp_Reg_Op_Name ("intrinsic");
             --Disp_Decl_Name (Get_Call_Subprg (Stmt));
diff --git a/ortho/mcode/ortho_code-x86-emits.adb b/ortho/mcode/ortho_code-x86-emits.adb
index 4a9040190..12f1587b0 100644
--- a/ortho/mcode/ortho_code-x86-emits.adb
+++ b/ortho/mcode/ortho_code-x86-emits.adb
@@ -792,20 +792,28 @@ package body Ortho_Code.X86.Emits is
 
    procedure Emit_Setup_Frame (Stmt : O_Enode)
    is
-      use Ortho_Code.Decls;
-      Subprg : O_Dnode;
-      Val : Unsigned_32;
+      Val : constant Int32 := Get_Stack_Adjust (Stmt);
    begin
-      Subprg := Get_Call_Subprg (Stmt);
-      Val := Unsigned_32 (Get_Subprg_Stack (Subprg));
-      --  Pad the stack if necessary.
-      Val := Val and (Flags.Stack_Boundary - 1);
-      if Val /= 0 then
+      if Val > 0 then
          Start_Insn;
          --  subl esp, val
          Gen_B8 (2#100000_11#);
          Gen_B8 (2#11_101_100#);
-         Gen_B8 (Byte (Flags.Stack_Boundary - Val));
+         Gen_B8 (Byte (Val));
+         End_Insn;
+      elsif Val < 0 then
+         Start_Insn;
+         if -Val <= 127 then
+            --  addl esp, val
+            Gen_B8 (2#100000_11#);
+            Gen_B8 (2#11_000_100#);
+            Gen_B8 (Byte (-Val));
+         else
+            --  addl esp, val
+            Gen_B8 (2#100000_01#);
+            Gen_B8 (2#11_000_100#);
+            Gen_Le32 (Unsigned_32 (-Val));
+         end if;
          End_Insn;
       end if;
    end Emit_Setup_Frame;
@@ -815,29 +823,10 @@ package body Ortho_Code.X86.Emits is
       use Ortho_Code.Decls;
       Subprg : O_Dnode;
       Sym : Symbol;
-      Val : Unsigned_32;
    begin
       Subprg := Get_Call_Subprg (Stmt);
       Sym := Get_Decl_Symbol (Subprg);
       Gen_Call (Sym);
-      Val := Unsigned_32 (Get_Subprg_Stack (Subprg));
-      Val := (Val + Flags.Stack_Boundary - 1)
-        and not (Flags.Stack_Boundary - 1);
-      if Val /= 0 then
-         Start_Insn;
-         if Val <= 127 then
-            --  addl esp, val
-            Gen_B8 (2#100000_11#);
-            Gen_B8 (2#11_000_100#);
-            Gen_B8 (Byte (Val));
-         else
-            --  addl esp, val
-            Gen_B8 (2#100000_01#);
-            Gen_B8 (2#11_000_100#);
-            Gen_Le32 (Val);
-         end if;
-         End_Insn;
-      end if;
    end Emit_Call;
 
    procedure Emit_Intrinsic (Stmt : O_Enode)
@@ -1853,12 +1842,8 @@ package body Ortho_Code.X86.Emits is
                when others =>
                   Error_Emit ("emit_insn: oe_arg", Stmt);
             end case;
-         when OE_Setup_Frame =>
-            pragma Warnings (Off);
-            if Flags.Stack_Boundary > 4 then
-               Emit_Setup_Frame (Stmt);
-            end if;
-            pragma Warnings (On);
+         when OE_Stack_Adjust =>
+            Emit_Setup_Frame (Stmt);
          when OE_Call =>
             Emit_Call (Stmt);
          when OE_Intrinsic =>
@@ -2007,7 +1992,11 @@ package body Ortho_Code.X86.Emits is
       Frame_Size : Unsigned_32;
       Saved_Regs_Size : Unsigned_32;
    begin
+      --  Switch to .text section and align the function (to avoid the nested
+      --  function trick and for performance).
       Set_Current_Section (Sect_Text);
+      Gen_Pow_Align (2);
+
       Subprg_Decl := Subprg.D_Decl;
       Sym := Get_Decl_Symbol (Subprg_Decl);
       case Get_Decl_Storage (Subprg_Decl) is
diff --git a/ortho/mcode/ortho_code-x86-insns.adb b/ortho/mcode/ortho_code-x86-insns.adb
index d3ea79233..9ef638505 100644
--- a/ortho/mcode/ortho_code-x86-insns.adb
+++ b/ortho/mcode/ortho_code-x86-insns.adb
@@ -15,6 +15,7 @@
 --  along with GCC; see the file COPYING.  If not, write to the Free
 --  Software Foundation, 59 Temple Place - Suite 330, Boston, MA
 --  02111-1307, USA.
+with Interfaces;
 with Ada.Text_IO;
 with Ortho_Code.Abi;
 with Ortho_Code.Decls; use Ortho_Code.Decls;
@@ -72,6 +73,10 @@ package body Ortho_Code.X86.Insns is
    Stack_Offset : Uns32 := 0;
    Stack_Max : Uns32 := 0;
 
+   --  Count how many bytes have been pushed on the stack, during a call. This
+   --  is used to correctly align the stack for nested calls.
+   Push_Offset : Uns32 := 0;
+
    --  STMT is an OE_END statement.
    --  Swap Stack_Offset with Max_Stack of STMT.
    procedure Swap_Stack_Offset (Blk : O_Dnode)
@@ -1004,15 +1009,30 @@ package body Ortho_Code.X86.Insns is
    function Gen_Call (Stmt : O_Enode; Reg : O_Reg; Pnum : O_Inum)
                      return O_Enode
    is
+      use Interfaces;
       Left : O_Enode;
       Reg_Res : O_Reg;
+      Subprg : O_Dnode;
+      Push_Size : Uns32;
+      Pad : Uns32;
+      Res_Stmt : O_Enode;
    begin
-      Link_Stmt
-        (New_Enode (OE_Setup_Frame, Mode_Nil, O_Tnode_Null,
-                    O_Enode (Get_Call_Subprg (Stmt)), O_Enode_Null));
+      --  Emit Setup_Frame (to align stack).
+      Subprg := Get_Call_Subprg (Stmt);
+      Push_Size := Uns32 (Get_Subprg_Stack (Subprg));
+      --  Pad the stack if necessary.
+      Pad := (Push_Size + Push_Offset) and Uns32 (Flags.Stack_Boundary - 1);
+      if Pad /= 0 then
+         Pad := Uns32 (Flags.Stack_Boundary) - Pad;
+         Link_Stmt (New_Enode (OE_Stack_Adjust, Mode_Nil, O_Tnode_Null,
+                               O_Enode (Pad), O_Enode_Null));
+      end if;
+      --  The stack has been adjusted by Pad bytes.
+      Push_Offset := Push_Offset + Pad;
+
+      --  Generate code for arguments (if any).
       Left := Get_Arg_Link (Stmt);
       if Left /= O_Enode_Null then
-         --  Generate code for arguments.
          Left := Gen_Insn (Left, R_None, Pnum);
       end if;
 
@@ -1022,9 +1042,22 @@ package body Ortho_Code.X86.Insns is
       Clobber_R32 (R_Cx);
       --  FIXME: fp regs.
 
+      --  Add the call.
       Reg_Res := Get_Call_Register (Get_Expr_Mode (Stmt));
       Set_Expr_Reg (Stmt, Reg_Res);
       Link_Stmt (Stmt);
+      Res_Stmt := Stmt;
+
+      if Push_Size + Pad /= 0 then
+         Res_Stmt :=
+           New_Enode (OE_Stack_Adjust, Get_Expr_Mode (Stmt), O_Tnode_Null,
+                      O_Enode (-Int32 (Push_Size + Pad)), O_Enode_Null);
+         Set_Expr_Reg (Res_Stmt, Reg_Res);
+         Link_Stmt (Res_Stmt);
+      end if;
+
+      --  The stack has been restored (just after the call).
+      Push_Offset := Push_Offset - (Push_Size + Pad);
 
       case Reg is
          when R_Any32
@@ -1037,18 +1070,18 @@ package body Ortho_Code.X86.Insns is
            | R_Ax
            | R_St0
            | R_Edx_Eax =>
-            Reg_Res := Alloc_Reg (Reg_Res, Stmt, Pnum);
-            return Stmt;
+            Reg_Res := Alloc_Reg (Reg_Res, Res_Stmt, Pnum);
+            return Res_Stmt;
          when R_Any_Cc =>
             --  Move to register.
             --  (use the 'test' instruction).
-            Alloc_Cc (Stmt, Pnum);
-            return Insert_Move (Stmt, R_Ne);
+            Alloc_Cc (Res_Stmt, Pnum);
+            return Insert_Move (Res_Stmt, R_Ne);
          when R_None =>
             if Reg_Res /= R_None then
                raise Program_Error;
             end if;
-            return Stmt;
+            return Res_Stmt;
          when others =>
             Error_Gen_Insn (Stmt, Reg);
       end case;
@@ -1621,6 +1654,7 @@ package body Ortho_Code.X86.Insns is
                      return Reload (Stmt, Reg, Pnum);
                   when Mode_U64
                     | Mode_I64 =>
+                     --  FIXME: align stack
                      Insert_Arg (Gen_Insn (Right, R_Irm, Num));
                      Insert_Arg (Gen_Insn (Left, R_Irm, Num));
                      return Insert_Intrinsic (Stmt, R_Edx_Eax, Pnum);
@@ -1821,9 +1855,11 @@ package body Ortho_Code.X86.Insns is
             end if;
             Left := Get_Arg_Link (Stmt);
             if Left /= O_Enode_Null then
-               --  Previous argument.
+               --  Recurse on next argument, so the first argument is pushed
+               --  the last one.
                Left := Gen_Insn (Left, R_None, Pnum);
             end if;
+
             Left := Get_Expr_Operand (Stmt);
             case Get_Expr_Mode (Left) is
                when Mode_F32 .. Mode_F64 =>
@@ -1835,6 +1871,8 @@ package body Ortho_Code.X86.Insns is
             end case;
             Left := Gen_Insn (Left, Reg_Res, Pnum);
             Set_Expr_Operand (Stmt, Left);
+            Push_Offset := Push_Offset +
+              Do_Align (Get_Mode_Size (Get_Expr_Mode (Left)), Mode_U32);
             Link_Stmt (Stmt);
             Free_Insn_Regs (Left);
             return Stmt;
@@ -2010,7 +2048,14 @@ package body Ortho_Code.X86.Insns is
          exit when Get_Expr_Kind (Stmt) = OE_Leave;
          Stmt := N_Stmt;
       end loop;
+
+      --  Keep stack depth for this subprogram.
       Subprg.Stack_Max := Stack_Max;
+
+      --  Sanity check: there must be no remaining pushed bytes.
+      if Push_Offset /= 0 then
+         raise Program_Error with "gen_subprg_insn: push_offset not 0";
+      end if;
    end Gen_Subprg_Insns;
 
 end Ortho_Code.X86.Insns;