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SingularityViewer/indra/llmath/llv4math.h
2011-04-17 14:37:08 -04:00

150 lines
4.9 KiB
C++

/**
* @file llv4math.h
* @brief LLV4* class header file - vector processor enabled math
*
* $LicenseInfo:firstyear=2007&license=viewergpl$
*
* Copyright (c) 2007-2009, Linden Research, Inc.
*
* Second Life Viewer Source Code
* The source code in this file ("Source Code") is provided by Linden Lab
* to you under the terms of the GNU General Public License, version 2.0
* ("GPL"), unless you have obtained a separate licensing agreement
* ("Other License"), formally executed by you and Linden Lab. Terms of
* the GPL can be found in doc/GPL-license.txt in this distribution, or
* online at http://secondlifegrid.net/programs/open_source/licensing/gplv2
*
* There are special exceptions to the terms and conditions of the GPL as
* it is applied to this Source Code. View the full text of the exception
* in the file doc/FLOSS-exception.txt in this software distribution, or
* online at
* http://secondlifegrid.net/programs/open_source/licensing/flossexception
*
* By copying, modifying or distributing this software, you acknowledge
* that you have read and understood your obligations described above,
* and agree to abide by those obligations.
*
* ALL LINDEN LAB SOURCE CODE IS PROVIDED "AS IS." LINDEN LAB MAKES NO
* WARRANTIES, EXPRESS, IMPLIED OR OTHERWISE, REGARDING ITS ACCURACY,
* COMPLETENESS OR PERFORMANCE.
* $/LicenseInfo$
*/
#ifndef LL_LLV4MATH_H
#define LL_LLV4MATH_H
// *NOTE: We do not support SSE acceleration on Windows builds.
// Our minimum specification for the viewer includes 1 GHz Athlon processors,
// which covers the Athlon Thunderbird series that does not support SSE.
//
// Our header files include statements like this
// const F32 HAVOK_TIMESTEP = 1.f / 45.f;
// This creates "globals" that are included in each .obj file. If a single
// .cpp file has SSE code generation turned on (eg, llviewerjointmesh_sse.cpp)
// these globals will be initialized using SSE instructions. This causes SL
// to crash before main() on processors without SSE. Untangling all these
// headers/variables is too much work for the small performance gains of
// vectorization.
//
// Therefore we only support vectorization on builds where the everything is
// built with SSE or Altivec. See https://jira.secondlife.com/browse/VWR-1610
// and https://jira.lindenlab.com/browse/SL-47720 for details.
//
// Sorry the code is such a mess. JC
#include "llpreprocessor.h"
//-----------------------------------------------------------------------------
//-----------------------------------------------------------------------------
// LLV4MATH - GNUC
//-----------------------------------------------------------------------------
//-----------------------------------------------------------------------------
#if LL_GNUC && __GNUC__ >= 4 && __SSE__
#define LL_VECTORIZE 1
#if LL_DARWIN
#include <Accelerate/Accelerate.h>
#include <xmmintrin.h>
typedef vFloat V4F32;
#else
#include <xmmintrin.h>
typedef float V4F32 __attribute__((vector_size(16)));
#endif
#endif
#if LL_GNUC
#define LL_LLV4MATH_ALIGN_PREFIX
#define LL_LLV4MATH_ALIGN_POSTFIX __attribute__((aligned(16)))
#endif
//-----------------------------------------------------------------------------
//-----------------------------------------------------------------------------
// LLV4MATH - MSVC
//-----------------------------------------------------------------------------
//-----------------------------------------------------------------------------
// Only vectorize if the entire Windows build uses SSE.
// _M_IX86_FP is set when SSE code generation is turned on, and I have
// confirmed this in VS2003, VS2003 SP1, and VS2005. JC
#if LL_MSVC && _M_IX86_FP
#define LL_VECTORIZE 1
#include <xmmintrin.h>
typedef __m128 V4F32;
#endif
#if LL_MSVC
#define LL_LLV4MATH_ALIGN_PREFIX __declspec(align(16))
#define LL_LLV4MATH_ALIGN_POSTFIX
#endif
//-----------------------------------------------------------------------------
//-----------------------------------------------------------------------------
// LLV4MATH - default - no vectorization
//-----------------------------------------------------------------------------
//-----------------------------------------------------------------------------
#if !LL_VECTORIZE
#define LL_VECTORIZE 0
struct V4F32 { F32 __pad__[4]; };
inline F32 llv4lerp(F32 a, F32 b, F32 w) { return ( b - a ) * w + a; }
#endif
#ifndef LL_LLV4MATH_ALIGN_PREFIX
# define LL_LLV4MATH_ALIGN_PREFIX
#endif
#ifndef LL_LLV4MATH_ALIGN_POSTFIX
# define LL_LLV4MATH_ALIGN_POSTFIX
#endif
//-----------------------------------------------------------------------------
//-----------------------------------------------------------------------------
// LLV4MATH
//-----------------------------------------------------------------------------
//-----------------------------------------------------------------------------
#define LLV4_NUM_AXIS 4
class LLV4Vector3;
class LLV4Matrix3;
class LLV4Matrix4;
#endif