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Diffstat (limited to 'src/corelib/tools/qsimd.cpp')
| -rw-r--r-- | src/corelib/tools/qsimd.cpp | 246 |
1 files changed, 246 insertions, 0 deletions
diff --git a/src/corelib/tools/qsimd.cpp b/src/corelib/tools/qsimd.cpp new file mode 100644 index 0000000..52d2cea --- /dev/null +++ b/src/corelib/tools/qsimd.cpp @@ -0,0 +1,246 @@ +/**************************************************************************** +** +** Copyright (C) 2010 Nokia Corporation and/or its subsidiary(-ies). +** All rights reserved. +** Contact: Nokia Corporation (qt-info@nokia.com) +** +** This file is part of the QtCore module of the Qt Toolkit. +** +** $QT_BEGIN_LICENSE:LGPL$ +** No Commercial Usage +** This file contains pre-release code and may not be distributed. +** You may use this file in accordance with the terms and conditions +** contained in the Technology Preview License Agreement accompanying +** this package. +** +** GNU Lesser General Public License Usage +** Alternatively, this file may be used under the terms of the GNU Lesser +** General Public License version 2.1 as published by the Free Software +** Foundation and appearing in the file LICENSE.LGPL included in the +** packaging of this file. Please review the following information to +** ensure the GNU Lesser General Public License version 2.1 requirements +** will be met: http://www.gnu.org/licenses/old-licenses/lgpl-2.1.html. +** +** In addition, as a special exception, Nokia gives you certain additional +** rights. These rights are described in the Nokia Qt LGPL Exception +** version 1.1, included in the file LGPL_EXCEPTION.txt in this package. +** +** If you have questions regarding the use of this file, please contact +** Nokia at qt-info@nokia.com. +** +** +** +** +** +** +** +** +** $QT_END_LICENSE$ +** +****************************************************************************/ + +#include "qsimd_p.h" +#include <QByteArray> + +QT_BEGIN_NAMESPACE + +uint qDetectCPUFeatures() +{ + static uint features = 0xffffffff; + if (features != 0xffffffff) + return features; + +#if defined (Q_OS_WINCE) +#if defined (ARM) + if (IsProcessorFeaturePresent(PF_ARM_INTEL_WMMX)) { + features = IWMMXT; + return features; + } +#elif defined(_X86_) + features = 0; +#if defined QT_HAVE_MMX + if (IsProcessorFeaturePresent(PF_MMX_INSTRUCTIONS_AVAILABLE)) + features |= MMX; +#endif +#if defined QT_HAVE_3DNOW + if (IsProcessorFeaturePresent(PF_3DNOW_INSTRUCTIONS_AVAILABLE)) + features |= MMX3DNOW; +#endif + return features; +#endif + features = 0; + return features; +#elif defined(QT_HAVE_IWMMXT) + // runtime detection only available when running as a previlegied process + static const bool doIWMMXT = !qgetenv("QT_NO_IWMMXT").toInt(); + features = doIWMMXT ? IWMMXT : 0; + return features; +#elif defined(QT_HAVE_NEON) + static const bool doNEON = !qgetenv("QT_NO_NEON").toInt(); + features = doNEON ? NEON : 0; + return features; +#else + features = 0; +#if defined(__x86_64__) || defined(Q_OS_WIN64) + features = MMX|SSE|SSE2|CMOV; +#elif defined(__ia64__) + features = MMX|SSE|SSE2; +#elif defined(__i386__) || defined(_M_IX86) + unsigned int extended_result = 0; + uint result = 0; + /* see p. 118 of amd64 instruction set manual Vol3 */ +#if defined(Q_CC_GNU) + asm ("push %%ebx\n" + "pushf\n" + "pop %%eax\n" + "mov %%eax, %%ebx\n" + "xor $0x00200000, %%eax\n" + "push %%eax\n" + "popf\n" + "pushf\n" + "pop %%eax\n" + "xor %%edx, %%edx\n" + "xor %%ebx, %%eax\n" + "jz 1f\n" + + "mov $0x00000001, %%eax\n" + "cpuid\n" + "1:\n" + "pop %%ebx\n" + "mov %%edx, %0\n" + : "=r" (result) + : + : "%eax", "%ecx", "%edx" + ); + + asm ("push %%ebx\n" + "pushf\n" + "pop %%eax\n" + "mov %%eax, %%ebx\n" + "xor $0x00200000, %%eax\n" + "push %%eax\n" + "popf\n" + "pushf\n" + "pop %%eax\n" + "xor %%edx, %%edx\n" + "xor %%ebx, %%eax\n" + "jz 2f\n" + + "mov $0x80000000, %%eax\n" + "cpuid\n" + "cmp $0x80000000, %%eax\n" + "jbe 2f\n" + "mov $0x80000001, %%eax\n" + "cpuid\n" + "2:\n" + "pop %%ebx\n" + "mov %%edx, %0\n" + : "=r" (extended_result) + : + : "%eax", "%ecx", "%edx" + ); +#elif defined (Q_OS_WIN) + _asm { + push eax + push ebx + push ecx + push edx + pushfd + pop eax + mov ebx, eax + xor eax, 00200000h + push eax + popfd + pushfd + pop eax + mov edx, 0 + xor eax, ebx + jz skip + + mov eax, 1 + cpuid + mov result, edx + skip: + pop edx + pop ecx + pop ebx + pop eax + } + + _asm { + push eax + push ebx + push ecx + push edx + pushfd + pop eax + mov ebx, eax + xor eax, 00200000h + push eax + popfd + pushfd + pop eax + mov edx, 0 + xor eax, ebx + jz skip2 + + mov eax, 80000000h + cpuid + cmp eax, 80000000h + jbe skip2 + mov eax, 80000001h + cpuid + mov extended_result, edx + skip2: + pop edx + pop ecx + pop ebx + pop eax + } +#endif + + // result now contains the standard feature bits + if (result & (1u << 15)) + features |= CMOV; + if (result & (1u << 23)) + features |= MMX; + if (extended_result & (1u << 22)) + features |= MMXEXT; + if (extended_result & (1u << 31)) + features |= MMX3DNOW; + if (extended_result & (1u << 30)) + features |= MMX3DNOWEXT; + if (result & (1u << 25)) + features |= SSE; + if (result & (1u << 26)) + features |= SSE2; +#endif // i386 + +#if defined(QT_HAVE_MMX) + if (qgetenv("QT_NO_MMX").toInt()) + features ^= MMX; +#endif + if (qgetenv("QT_NO_MMXEXT").toInt()) + features ^= MMXEXT; + +#if defined(QT_HAVE_3DNOW) + if (qgetenv("QT_NO_3DNOW").toInt()) + features ^= MMX3DNOW; +#endif + if (qgetenv("QT_NO_3DNOWEXT").toInt()) + features ^= MMX3DNOWEXT; + +#if defined(QT_HAVE_SSE) + if (qgetenv("QT_NO_SSE").toInt()) + features ^= SSE; +#endif +#if defined(QT_HAVE_SSE2) + if (qgetenv("QT_NO_SSE2").toInt()) + features ^= SSE2; +#endif + + return features; +#endif +} + +QT_END_NAMESPACE |