diff options
Diffstat (limited to 'gcc/ada/layout.adb')
| -rw-r--r-- | gcc/ada/layout.adb | 100 |
1 files changed, 92 insertions, 8 deletions
diff --git a/gcc/ada/layout.adb b/gcc/ada/layout.adb index 2cf97cb2fb8..8245e9556d7 100644 --- a/gcc/ada/layout.adb +++ b/gcc/ada/layout.adb @@ -8,7 +8,7 @@ -- -- -- $Revision$ -- -- --- Copyright (C) 2001 Free Software Foundation, Inc. -- +-- Copyright (C) 2001-2002 Free Software Foundation, Inc. -- -- -- -- GNAT is free software; you can redistribute it and/or modify it under -- -- terms of the GNU General Public License as published by the Free Soft- -- @@ -171,6 +171,12 @@ package body Layout is -- E are set (either from previously given values, or from the newly -- computed values, as appropriate). + procedure Set_Composite_Alignment (E : Entity_Id); + -- This procedure is called for record types and subtypes, and also for + -- atomic array types and subtypes. If no alignment is set, and the size + -- is 2 or 4 (or 8 if the word size is 8), then the alignment is set to + -- match the size. + ---------------------------- -- Adjust_Esize_Alignment -- ---------------------------- @@ -930,16 +936,21 @@ package body Layout is Insert_Typ := E; end if; - -- Cannot do anything if Esize of component type unknown + -- Deal with component size if base type - if Unknown_Esize (Ctyp) then - return; - end if; + if Ekind (E) = E_Array_Type then + + -- Cannot do anything if Esize of component type unknown + + if Unknown_Esize (Ctyp) then + return; + end if; - -- Set component size if not set already + -- Set component size if not set already - if Unknown_Component_Size (E) then - Set_Component_Size (E, Esize (Ctyp)); + if Unknown_Component_Size (E) then + Set_Component_Size (E, Esize (Ctyp)); + end if; end if; -- (RM 13.3 (48)) says that the size of an unconstrained array @@ -2263,9 +2274,30 @@ package body Layout is if Frontend_Layout_On_Target then if Is_Array_Type (E) and then not Is_Bit_Packed_Array (E) then Layout_Array_Type (E); + return; elsif Is_Record_Type (E) then Layout_Record_Type (E); + return; end if; + + -- Special remaining processing for record types with a known size + -- of 16, 32, or 64 bits whose alignment is not yet set. For these + -- types, we set a corresponding alignment matching the size if + -- possible, or as large as possible if not. + + elsif Is_Record_Type (E) and not Debug_Flag_Q then + Set_Composite_Alignment (E); + + -- For arrays, we only do this processing for arrays that are + -- required to be atomic. Here, we really need to have proper + -- alignment, but for the normal case of non-atomic arrays it + -- seems better to use the component alignment as the default. + + elsif Is_Array_Type (E) + and then Is_Atomic (E) + and then not Debug_Flag_Q + then + Set_Composite_Alignment (E); end if; end Layout_Type; @@ -2379,6 +2411,58 @@ package body Layout is end if; end Set_And_Check_Static_Size; + ----------------------------- + -- Set_Composite_Alignment -- + ----------------------------- + + procedure Set_Composite_Alignment (E : Entity_Id) is + Siz : Uint; + Align : Nat; + + begin + if Unknown_Alignment (E) then + if Known_Static_Esize (E) then + Siz := Esize (E); + + elsif Unknown_Esize (E) + and then Known_Static_RM_Size (E) + then + Siz := RM_Size (E); + + else + return; + end if; + + -- Size is known, alignment is not set + + if Siz = System_Storage_Unit then + Align := 1; + elsif Siz = 2 * System_Storage_Unit then + Align := 2; + elsif Siz = 4 * System_Storage_Unit then + Align := 4; + elsif Siz = 8 * System_Storage_Unit then + Align := 8; + else + return; + end if; + + if Align > Maximum_Alignment then + Align := Maximum_Alignment; + end if; + + if Align > System_Word_Size / System_Storage_Unit then + Align := System_Word_Size / System_Storage_Unit; + end if; + + Set_Alignment (E, UI_From_Int (Align)); + + if Unknown_Esize (E) then + Set_Esize (E, UI_From_Int (Align * System_Storage_Unit)); + end if; + end if; + end Set_Composite_Alignment; + -------------------------- -- Set_Discrete_RM_Size -- -------------------------- |