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Diffstat (limited to 'gcc-4.2.1/gcc/ada/s-hibaen.ads')
| -rw-r--r-- | gcc-4.2.1/gcc/ada/s-hibaen.ads | 101 |
1 files changed, 101 insertions, 0 deletions
diff --git a/gcc-4.2.1/gcc/ada/s-hibaen.ads b/gcc-4.2.1/gcc/ada/s-hibaen.ads new file mode 100644 index 000000000..90ba0155d --- /dev/null +++ b/gcc-4.2.1/gcc/ada/s-hibaen.ads @@ -0,0 +1,101 @@ +------------------------------------------------------------------------------ +-- -- +-- GNAT RUN-TIME COMPONENTS -- +-- -- +-- S Y S T E M . H I E _ B A C K _ E N D -- +-- -- +-- S p e c -- +-- -- +-- Copyright (C) 2001-2003 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- -- +-- ware Foundation; either version 2, or (at your option) any later ver- -- +-- sion. GNAT is distributed in the hope that it will be useful, but WITH- -- +-- OUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY -- +-- or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License -- +-- for more details. You should have received a copy of the GNU General -- +-- Public License distributed with GNAT; see file COPYING. If not, write -- +-- to the Free Software Foundation, 51 Franklin Street, Fifth Floor, -- +-- Boston, MA 02110-1301, USA. -- +-- -- +-- As a special exception, if other files instantiate generics from this -- +-- unit, or you link this unit with other files to produce an executable, -- +-- this unit does not by itself cause the resulting executable to be -- +-- covered by the GNU General Public License. This exception does not -- +-- however invalidate any other reasons why the executable file might be -- +-- covered by the GNU Public License. -- +-- -- +-- GNAT was originally developed by the GNAT team at New York University. -- +-- Extensive contributions were provided by Ada Core Technologies Inc. -- +-- -- +------------------------------------------------------------------------------ + +-- This package provides an interface used in HI-E mode to determine +-- whether or not the back end can handle certain constructs in a manner +-- that is consistent with certification requirements. + +-- The approach is to define entities which may or may not be present in +-- a HI-E configured library. If the entity is present then the compiler +-- operating in HI-E mode will allow the corresponding operation. If the +-- entity is not present, the corresponding construct will be flagged as +-- not permitted in High Integrity mode. + +-- The default version of this unit delivered with the HI-E compiler is +-- configured in a manner appropriate for the target, but it is possible +-- to reconfigure the run-time to change the settings as required. + +-- This unit is not used and never accessed by the compiler unless it is +-- operating in HI-E mode, so the settings are irrelevant. However, we +-- do include a standard version with all entities present in the standard +-- run-time for use when pragma No_Run_Time is specified. + +package System.HIE_Back_End is + + type Dummy is null record; + pragma Suppress_Initialization (Dummy); + -- This is the type used for the entities below. No properties of this + -- type are ever referenced, and in particular, the entities are defined + -- as variables, but their values are never referenced + + HIE_64_Bit_Divides : Dummy; + -- This entity controls whether the front end allows 64-bit integer + -- divide operations, including the case where division of 32-bit + -- fixed-point operands requires 64-bit arithmetic. This can safely + -- be set as High_Integrity on 64-bit machines which provide this + -- operation as a native instruction, but on most 32-bit machines + -- a run time call (e.g. to __divdi3 in gcclib) is required. If a + -- certifiable version of this routine is available, then setting + -- this entity to High_Integrity with a pragma will cause appropriate + -- calls to be generated, allowing 64-bit integer division operations. + + HIE_Long_Shifts : Dummy; + -- This entity controls whether the front end allows generation of + -- long shift instructions, i.e. shifts that operate on 64-bit values. + -- Such shifts are required for the implementation of fixed-point + -- types longer than 32 bits. This can safetly be set as High_Integrity + -- on 64-bit machines that provide this operation at the hardware level, + -- but on some 32-bit machines a run time call is required. If there + -- is a certifiable version available of the relevant run-time routines, + -- then setting this entity to High_Integrity with a pragma will cause + -- appropriate calls to be generated, allowing the declaration and use + -- of fixed-point types longer than 32 bits. + + HIE_Aggregates : Dummy; + -- In the general case, the use of aggregates may generate calls + -- to run-time routines in the C library, including memset, memcpy, + -- memmove, and bcopy. This entity can be set to High_Integrity with + -- a pragma if certifiable versions of all these routines are available, + -- in which case aggregates are permitted in HI-E mode. Otherwise the + -- HI-E compiler will reject any use of aggregates. + + HIE_Composite_Assignments : Dummy; + -- The assignment of composite objects other than small records and + -- arrays whose size is 64-bits or less and is set by an explicit + -- size clause may generate calls to memcpy, memmove, and bcopy. + -- If certifiable versions of all these routines are available, then + -- this entity may be set to High_Integrity using a pragma, in which + -- case such assignments are permitted. Otherwise the HI-E compiler + -- will reject any such composite assignments. + +end System.HIE_Back_End; |