GCC Middle and Back End API Reference
Data Fields
cumulative_args_t Union Reference

#include <target.h>

Data Fields

void * p

Detailed Description

Data structure definitions for a generic GCC target. Copyright (C) 2001-2013 Free Software Foundation, Inc.

This program is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 3, or (at your option) any later version.

This program is distributed in the hope that it will be useful, but WITHOUT 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 along with this program; see the file COPYING3. If not see http://www.gnu.org/licenses/.

In other words, you are welcome to use, share and improve this program. You are forbidden to forbid anyone else to use, share and improve what you give them. Help stamp out software-hoarding! This file contains a data structure that describes a GCC target. At present it is incomplete, but in future it should grow to contain most or all target machine and target O/S specific information.

This structure has its initializer declared in target-def.h in the form of large macro TARGET_INITIALIZER that expands to many smaller macros.

The smaller macros each initialize one component of the structure, and each has a default. Each target should have a file that includes target.h and target-def.h, and overrides any inappropriate defaults by undefining the relevant macro and defining a suitable replacement. That file should then contain the definition of "targetm" like so:

struct gcc_target targetm = TARGET_INITIALIZER;

Doing things this way allows us to bring together everything that defines a GCC target. By supplying a default that is appropriate to most targets, we can easily add new items without needing to edit dozens of target configuration files. It should also allow us to gradually reduce the amount of conditional compilation that is scattered throughout GCC. When using a GCC build compiler, we could use attribute((transparent_union)) to get cumulative_args_t function arguments passed like scalars where the ABI would mandate a less efficient way of argument passing otherwise. However, that would come at the cost of less type-safe !ENABLE_CHECKING compilation.

Field Documentation

void* cumulative_args_t::p
The documentation for this union was generated from the following file: