dhewm3-sdk/sys/platform.h
Daniel Gibson ba6ba086b2 Don't use GCC's __builtin_alloca_with_align(), fix #572
turns out that __builtin_alloca_with_align() might releases the
allocated memory at the end of the block it was allocated in, instead
of the end of the function (which is the behavior of regular alloca()
and __builtin_alloca()): "The lifetime of the allocated object ends at
 the end of the block in which the function was called. The allocated
 storage is released no later than just before the calling function
 returns to its caller, but may be released at the end of the block in
 which the function was called."
https://gcc.gnu.org/onlinedocs/gcc/Other-Builtins.html#index-_005f_005fbuiltin_005falloca_005fwith_005falign

Clang also supports __builtin_alloca_with_align(), but always releases
the memory at the end of the function.

And it seems that newer GCC versions also tend to release it at the
end of the function, but GCC 4.7.2 (that I use for the official Linux
release binaries) didn't, and that caused weird graphical glitches.
But as I don't want to rely on newer GCC versions behaving like this
(and the documentation explicitly says that it *may* be released at
 the end of the block, but will definitely be released at the end of
 the function), I removed all usage of __builtin_alloca_with_align().

(Side-Note: GCC only started documenting the behavior of
 __builtin_alloca and __builtin_alloca_with_align at all with GCC 6.1.0)
2024-04-19 07:39:56 +02:00

290 lines
8.4 KiB
C

/*
===========================================================================
Doom 3 GPL Source Code
Copyright (C) 1999-2011 id Software LLC, a ZeniMax Media company.
This file is part of the Doom 3 GPL Source Code ("Doom 3 Source Code").
Doom 3 Source Code 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 of the License, or
(at your option) any later version.
Doom 3 Source Code 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 Doom 3 Source Code. If not, see <http://www.gnu.org/licenses/>.
In addition, the Doom 3 Source Code is also subject to certain additional terms. You should have received a copy of these additional terms immediately following the terms and conditions of the GNU General Public License which accompanied the Doom 3 Source Code. If not, please request a copy in writing from id Software at the address below.
If you have questions concerning this license or the applicable additional terms, you may contact in writing id Software LLC, c/o ZeniMax Media Inc., Suite 120, Rockville, Maryland 20850 USA.
===========================================================================
*/
#ifndef __PLATFORM__
#define __PLATFORM__
#include "config.h"
#include "framework/BuildDefines.h"
#ifdef _WIN32
#include <malloc.h> // _alloca()
#endif
// NOTE: By default Win32 uses a 1MB stack. Doom3 1.3.1 uses 4MB (probably set after compiling with EDITBIN /STACK
// dhewm3 now uses a 8MB stack, set with a linker flag in CMakeLists.txt (/STACK:8388608 for MSVC, -Wl,--stack,8388608 for mingw)
// Linux has a 8MB stack by default, and so does macOS, at least for the main thread
// anyway, a 2MB limit alloca should be safe even when using it multiple times in the same function
#define ID_MAX_ALLOCA_SIZE 2097152 // 2MB
/*
===============================================================================
Non-portable system services.
===============================================================================
*/
// AROS
#if defined(__AROS__)
#define _alloca alloca
#define _alloca16( x ) ((void *)((((uintptr_t)alloca( (x)+15 )) + 15) & ~15))
#ifdef GAME_DLL
#define ID_GAME_API __attribute__((visibility ("default")))
#else
#define ID_GAME_API
#endif
#define ALIGN16( x ) x __attribute__ ((aligned (16)))
#define PACKED __attribute__((packed))
#define PATHSEPERATOR_STR "/"
#define PATHSEPERATOR_CHAR '/'
#define __cdecl
#define ASSERT assert
#define ID_INLINE inline
#define ID_STATIC_TEMPLATE
#define assertmem( x, y )
#endif
// Win32
#if defined(WIN32) || defined(_WIN32)
#ifdef __MINGW32__
#undef _alloca // in mingw _alloca is a #define
// NOTE: Do *not* use __builtin_alloca_with_align(), unlike regular alloca it frees at end of block instead of end of function !
#define _alloca16( x ) ( (void *) ( (assert((x)<ID_MAX_ALLOCA_SIZE)), ((((uintptr_t)__builtin_alloca( (x)+15 )) + 15) & ~15) ) )
#define _alloca( x ) ( (assert((x)<ID_MAX_ALLOCA_SIZE)), __builtin_alloca( (x) ) )
#else
#define _alloca16( x ) ( (void *) ( (assert((x)<ID_MAX_ALLOCA_SIZE)), ((((uintptr_t)_alloca( (x)+15 )) + 15) & ~15) ) )
#define _alloca( x ) ( (void *) ( (assert((x)<ID_MAX_ALLOCA_SIZE)), _alloca( (x) ) ) )
#endif
#define PATHSEPERATOR_STR "\\"
#define PATHSEPERATOR_CHAR '\\'
#ifdef _MSC_VER
#ifdef GAME_DLL
#define ID_GAME_API __declspec(dllexport)
#else
#define ID_GAME_API
#endif
#define ALIGN16( x ) __declspec(align(16)) x
#define PACKED
#define ID_INLINE __forceinline
// DG: alternative to forced inlining of ID_INLINE for functions that do alloca()
// and are called in a loop so inlining them might cause stack overflow
#define ID_MAYBE_INLINE __inline
#define ID_STATIC_TEMPLATE static
#define assertmem( x, y ) assert( _CrtIsValidPointer( x, y, true ) )
#else
#ifdef GAME_DLL
#define ID_GAME_API __attribute__((visibility ("default")))
#else
#define ID_GAME_API
#endif
#define ALIGN16( x ) x __attribute__ ((aligned (16)))
#define PACKED __attribute__((packed))
#define ID_INLINE inline
#define ID_STATIC_TEMPLATE
#define assertmem( x, y )
#endif
#endif
// Setting D3_ARCH for VisualC++ from CMake doesn't work when using VS integrated CMake
// so set it in code instead
#ifdef _MSC_VER
#ifdef D3_ARCH
#undef D3_ARCH
#endif // D3_ARCH
#ifdef _M_X64
// this matches AMD64 and ARM64EC (but not regular ARM64), but they're supposed to be binary-compatible somehow, so whatever
#define D3_ARCH "x86_64"
#elif defined(_M_ARM64)
#define D3_ARCH "arm64"
#elif defined(_M_ARM)
#define D3_ARCH "arm"
#elif defined(_M_IX86)
#define D3_ARCH "x86"
#else
// if you're not targeting one of the aforementioned architectures,
// check https://learn.microsoft.com/en-us/cpp/preprocessor/predefined-macros
// to find out how to detect yours and add it here - and please send a patch :)
#error "Unknown CPU architecture!"
// (for a quick and dirty solution, comment out the previous line, but keep in mind
// that savegames may not be compatible with other builds of dhewm3)
#define D3_ARCH "UNKNOWN"
#endif // _M_X64 etc
#endif // _MSC_VER
// Mac OSX
#if defined(MACOS_X) || defined(__APPLE__)
#ifdef GAME_DLL
#define ID_GAME_API __attribute__((visibility ("default")))
#else
#define ID_GAME_API
#endif
#define ALIGN16( x ) x __attribute__ ((aligned (16)))
#define PACKED __attribute__((packed))
#define _alloca alloca
#define _alloca16( x ) ((void *)((((uintptr_t)alloca( (x)+15 )) + 15) & ~15))
#define PATHSEPERATOR_STR "/"
#define PATHSEPERATOR_CHAR '/'
#define __cdecl
#define ASSERT assert
#define ID_INLINE inline
#define ID_STATIC_TEMPLATE
#define assertmem( x, y )
#endif
// Unix
#ifdef __unix__
#ifdef __GNUC__
// NOTE: Do *not* use __builtin_alloca_with_align(), unlike regular alloca it frees at end of block instead of end of function !
#define _alloca16( x ) (({assert( (x)<ID_MAX_ALLOCA_SIZE );}),((void *)((((uintptr_t)__builtin_alloca( (x)+15 )) + 15) & ~15)))
#define _alloca( x ) ( ({assert((x)<ID_MAX_ALLOCA_SIZE);}), __builtin_alloca( (x) ) )
#else
#define _alloca( x ) (({assert( (x)<ID_MAX_ALLOCA_SIZE );}), alloca( (x) ))
#define _alloca16( x ) (({assert( (x)<ID_MAX_ALLOCA_SIZE );}),((void *)((((uintptr_t)alloca( (x)+15 )) + 15) & ~15)))
#endif
#ifdef GAME_DLL
#define ID_GAME_API __attribute__((visibility ("default")))
#else
#define ID_GAME_API
#endif
#define ALIGN16( x ) x
#define PACKED __attribute__((packed))
#define PATHSEPERATOR_STR "/"
#define PATHSEPERATOR_CHAR '/'
#define __cdecl
#define ASSERT assert
#define ID_INLINE inline
#define ID_STATIC_TEMPLATE
#define assertmem( x, y )
#endif
#ifndef ID_MAYBE_INLINE
// for MSVC it's __inline, otherwise just inline should work
#define ID_MAYBE_INLINE inline
#endif // ID_MAYBE_INLINE
#ifdef __GNUC__
#define id_attribute(x) __attribute__(x)
#else
#define id_attribute(x)
#endif
#if !defined(_MSC_VER)
// MSVC does not provide this C99 header
#include <inttypes.h>
#endif
#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <string.h>
#include <assert.h>
#include <time.h>
#include <ctype.h>
#include <cstddef>
#include <typeinfo>
#include <errno.h>
#include <math.h>
#ifdef _WIN32
#define WIN32_LEAN_AND_MEAN
#include <windows.h>
#undef FindText // stupid namespace poluting Microsoft monkeys
#endif
// Apple legacy
#ifdef __APPLE__
#include <Availability.h>
#ifdef __MAC_OS_X_VERSION_MIN_REQUIRED
#if __MAC_OS_X_VERSION_MIN_REQUIRED == 1040
#define OSX_TIGER
#elif __MAC_OS_X_VERSION_MIN_REQUIRED < 1060
#define OSX_LEOPARD
#endif
#endif
#endif
#define ID_TIME_T time_t
typedef unsigned char byte; // 8 bits
typedef unsigned short word; // 16 bits
typedef unsigned int dword; // 32 bits
typedef unsigned int uint;
typedef unsigned long ulong;
typedef int qhandle_t;
#ifndef NULL
#define NULL ((void *)0)
#endif
#ifndef BIT
#define BIT( num ) ( 1 << ( num ) )
#endif
#define MAX_STRING_CHARS 1024 // max length of a string
// maximum world size
#define MAX_WORLD_COORD ( 128 * 1024 )
#define MIN_WORLD_COORD ( -128 * 1024 )
#define MAX_WORLD_SIZE ( MAX_WORLD_COORD - MIN_WORLD_COORD )
#endif