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mpv/cpudetect.c
diego 8c514af56c Wrap HAVE_XXX macros with RUNTIME_CPUDETECT, because when RUNTIME_CPUDETECT is 
enabled, checking HAVE_XXX and disabling that CPU feature is meaningless.
patch by KO Myung-Hun, komh chollian net


git-svn-id: svn://svn.mplayerhq.hu/mplayer/trunk@26094 b3059339-0415-0410-9bf9-f77b7e298cf2
2008-02-24 18:21:41 +00:00

615 lines
18 KiB
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#include "config.h"
#include "cpudetect.h"
#include "mp_msg.h"
CpuCaps gCpuCaps;
#ifdef HAVE_MALLOC_H
#include <malloc.h>
#endif
#include <stdlib.h>
#ifdef ARCH_X86
#include <stdio.h>
#include <string.h>
#if defined (__NetBSD__) || defined(__OpenBSD__)
#include <sys/param.h>
#include <sys/sysctl.h>
#include <machine/cpu.h>
#endif
#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || defined(__DragonFly__) || defined(__APPLE__)
#include <sys/types.h>
#include <sys/sysctl.h>
#endif
#ifdef __linux__
#include <signal.h>
#endif
#ifdef WIN32
#include <windows.h>
#endif
#ifdef __OS2__
#define INCL_DOS
#include <os2.h>
#endif
#ifdef __AMIGAOS4__
#include <proto/exec.h>
#endif
/* Thanks to the FreeBSD project for some of this cpuid code, and
* help understanding how to use it. Thanks to the Mesa
* team for SSE support detection and more cpu detect code.
*/
/* I believe this code works. However, it has only been used on a PII and PIII */
static void check_os_katmai_support( void );
#if 1
// return TRUE if cpuid supported
static int has_cpuid(void)
{
long a, c;
// code from libavcodec:
__asm__ __volatile__ (
/* See if CPUID instruction is supported ... */
/* ... Get copies of EFLAGS into eax and ecx */
"pushf\n\t"
"pop %0\n\t"
"mov %0, %1\n\t"
/* ... Toggle the ID bit in one copy and store */
/* to the EFLAGS reg */
"xor $0x200000, %0\n\t"
"push %0\n\t"
"popf\n\t"
/* ... Get the (hopefully modified) EFLAGS */
"pushf\n\t"
"pop %0\n\t"
: "=a" (a), "=c" (c)
:
: "cc"
);
return (a!=c);
}
#endif
static void
do_cpuid(unsigned int ax, unsigned int *p)
{
#if 0
__asm __volatile(
"cpuid;"
: "=a" (p[0]), "=b" (p[1]), "=c" (p[2]), "=d" (p[3])
: "0" (ax)
);
#else
// code from libavcodec:
__asm __volatile
("mov %%"REG_b", %%"REG_S"\n\t"
"cpuid\n\t"
"xchg %%"REG_b", %%"REG_S
: "=a" (p[0]), "=S" (p[1]),
"=c" (p[2]), "=d" (p[3])
: "0" (ax));
#endif
}
void GetCpuCaps( CpuCaps *caps)
{
unsigned int regs[4];
unsigned int regs2[4];
memset(caps, 0, sizeof(*caps));
caps->isX86=1;
caps->cl_size=32; /* default */
if (!has_cpuid()) {
mp_msg(MSGT_CPUDETECT,MSGL_WARN,"CPUID not supported!??? (maybe an old 486?)\n");
return;
}
do_cpuid(0x00000000, regs); // get _max_ cpuid level and vendor name
mp_msg(MSGT_CPUDETECT,MSGL_V,"CPU vendor name: %.4s%.4s%.4s max cpuid level: %d\n",
(char*) (regs+1),(char*) (regs+3),(char*) (regs+2), regs[0]);
if (regs[0]>=0x00000001)
{
char *tmpstr, *ptmpstr;
unsigned cl_size;
do_cpuid(0x00000001, regs2);
caps->cpuType=(regs2[0] >> 8)&0xf;
caps->cpuModel=(regs2[0] >> 4)&0xf;
// see AMD64 Architecture Programmer's Manual, Volume 3: General-purpose and
// System Instructions, Table 3-2: Effective family computation, page 120.
if(caps->cpuType==0xf){
// use extended family (P4, IA64, K8)
caps->cpuType=0xf+((regs2[0]>>20)&255);
}
if(caps->cpuType==0xf || caps->cpuType==6)
caps->cpuModel |= ((regs2[0]>>16)&0xf) << 4;
caps->cpuStepping=regs2[0] & 0xf;
// general feature flags:
caps->hasTSC = (regs2[3] & (1 << 8 )) >> 8; // 0x0000010
caps->hasMMX = (regs2[3] & (1 << 23 )) >> 23; // 0x0800000
caps->hasSSE = (regs2[3] & (1 << 25 )) >> 25; // 0x2000000
caps->hasSSE2 = (regs2[3] & (1 << 26 )) >> 26; // 0x4000000
caps->hasMMX2 = caps->hasSSE; // SSE cpus supports mmxext too
cl_size = ((regs2[1] >> 8) & 0xFF)*8;
if(cl_size) caps->cl_size = cl_size;
ptmpstr=tmpstr=GetCpuFriendlyName(regs, regs2);
while(*ptmpstr == ' ') // strip leading spaces
ptmpstr++;
mp_msg(MSGT_CPUDETECT,MSGL_INFO,"CPU: %s ", ptmpstr);
free(tmpstr);
mp_msg(MSGT_CPUDETECT,MSGL_INFO,"(Family: %d, Model: %d, Stepping: %d)\n",
caps->cpuType, caps->cpuModel, caps->cpuStepping);
}
do_cpuid(0x80000000, regs);
if (regs[0]>=0x80000001) {
mp_msg(MSGT_CPUDETECT,MSGL_V,"extended cpuid-level: %d\n",regs[0]&0x7FFFFFFF);
do_cpuid(0x80000001, regs2);
caps->hasMMX |= (regs2[3] & (1 << 23 )) >> 23; // 0x0800000
caps->hasMMX2 |= (regs2[3] & (1 << 22 )) >> 22; // 0x400000
caps->has3DNow = (regs2[3] & (1 << 31 )) >> 31; //0x80000000
caps->has3DNowExt = (regs2[3] & (1 << 30 )) >> 30;
}
if(regs[0]>=0x80000006)
{
do_cpuid(0x80000006, regs2);
mp_msg(MSGT_CPUDETECT,MSGL_V,"extended cache-info: %d\n",regs2[2]&0x7FFFFFFF);
caps->cl_size = regs2[2] & 0xFF;
}
mp_msg(MSGT_CPUDETECT,MSGL_V,"Detected cache-line size is %u bytes\n",caps->cl_size);
#if 0
mp_msg(MSGT_CPUDETECT,MSGL_INFO,"cpudetect: MMX=%d MMX2=%d SSE=%d SSE2=%d 3DNow=%d 3DNowExt=%d\n",
gCpuCaps.hasMMX,
gCpuCaps.hasMMX2,
gCpuCaps.hasSSE,
gCpuCaps.hasSSE2,
gCpuCaps.has3DNow,
gCpuCaps.has3DNowExt );
#endif
/* FIXME: Does SSE2 need more OS support, too? */
#if defined(__linux__) || defined(__FreeBSD__) || defined(__FreeBSD_kernel__) \
|| defined(__NetBSD__) || defined(__OpenBSD__) || defined(__DragonFly__) \
|| defined(__APPLE__) || defined(__CYGWIN__) || defined(__MINGW32__) \
|| defined(__OS2__)
if (caps->hasSSE)
check_os_katmai_support();
if (!caps->hasSSE)
caps->hasSSE2 = 0;
#else
caps->hasSSE=0;
caps->hasSSE2 = 0;
#endif
// caps->has3DNow=1;
// caps->hasMMX2 = 0;
// caps->hasMMX = 0;
#ifndef RUNTIME_CPUDETECT
#ifndef HAVE_MMX
if(caps->hasMMX) mp_msg(MSGT_CPUDETECT,MSGL_WARN,"MMX supported but disabled\n");
caps->hasMMX=0;
#endif
#ifndef HAVE_MMX2
if(caps->hasMMX2) mp_msg(MSGT_CPUDETECT,MSGL_WARN,"MMX2 supported but disabled\n");
caps->hasMMX2=0;
#endif
#ifndef HAVE_SSE
if(caps->hasSSE) mp_msg(MSGT_CPUDETECT,MSGL_WARN,"SSE supported but disabled\n");
caps->hasSSE=0;
#endif
#ifndef HAVE_SSE2
if(caps->hasSSE2) mp_msg(MSGT_CPUDETECT,MSGL_WARN,"SSE2 supported but disabled\n");
caps->hasSSE2=0;
#endif
#ifndef HAVE_3DNOW
if(caps->has3DNow) mp_msg(MSGT_CPUDETECT,MSGL_WARN,"3DNow supported but disabled\n");
caps->has3DNow=0;
#endif
#ifndef HAVE_3DNOWEX
if(caps->has3DNowExt) mp_msg(MSGT_CPUDETECT,MSGL_WARN,"3DNowExt supported but disabled\n");
caps->has3DNowExt=0;
#endif
#endif // RUNTIME_CPUDETECT
}
#define CPUID_EXTFAMILY ((regs2[0] >> 20)&0xFF) /* 27..20 */
#define CPUID_EXTMODEL ((regs2[0] >> 16)&0x0F) /* 19..16 */
#define CPUID_TYPE ((regs2[0] >> 12)&0x04) /* 13..12 */
#define CPUID_FAMILY ((regs2[0] >> 8)&0x0F) /* 11..08 */
#define CPUID_MODEL ((regs2[0] >> 4)&0x0F) /* 07..04 */
#define CPUID_STEPPING ((regs2[0] >> 0)&0x0F) /* 03..00 */
char *GetCpuFriendlyName(unsigned int regs[], unsigned int regs2[]){
#include "cputable.h" /* get cpuname and cpuvendors */
char vendor[13];
char *retname;
int i;
if (NULL==(retname=malloc(256))) {
mp_msg(MSGT_CPUDETECT,MSGL_FATAL,"Error: GetCpuFriendlyName() not enough memory\n");
exit(1);
}
sprintf(vendor,"%.4s%.4s%.4s",(char*)(regs+1),(char*)(regs+3),(char*)(regs+2));
do_cpuid(0x80000000,regs);
if (regs[0] >= 0x80000004)
{
// CPU has built-in namestring
retname[0] = '\0';
for (i = 0x80000002; i <= 0x80000004; i++)
{
do_cpuid(i, regs);
strncat(retname, (char*)regs, 16);
}
return retname;
}
for(i=0; i<MAX_VENDORS; i++){
if(!strcmp(cpuvendors[i].string,vendor)){
if(cpuname[i][CPUID_FAMILY][CPUID_MODEL]){
snprintf(retname,255,"%s %s",cpuvendors[i].name,cpuname[i][CPUID_FAMILY][CPUID_MODEL]);
} else {
snprintf(retname,255,"unknown %s %d. Generation CPU",cpuvendors[i].name,CPUID_FAMILY);
mp_msg(MSGT_CPUDETECT,MSGL_WARN,"unknown %s CPU:\n",cpuvendors[i].name);
mp_msg(MSGT_CPUDETECT,MSGL_WARN,"Vendor: %s\n",cpuvendors[i].string);
mp_msg(MSGT_CPUDETECT,MSGL_WARN,"Type: %d\n",CPUID_TYPE);
mp_msg(MSGT_CPUDETECT,MSGL_WARN,"Family: %d (ext: %d)\n",CPUID_FAMILY,CPUID_EXTFAMILY);
mp_msg(MSGT_CPUDETECT,MSGL_WARN,"Model: %d (ext: %d)\n",CPUID_MODEL,CPUID_EXTMODEL);
mp_msg(MSGT_CPUDETECT,MSGL_WARN,"Stepping: %d\n",CPUID_STEPPING);
mp_msg(MSGT_CPUDETECT,MSGL_WARN,"Please send the above info along with the exact CPU name"
"to the MPlayer-Developers, so we can add it to the list!\n");
}
}
}
retname[255] = 0;
//printf("Detected CPU: %s\n", retname);
return retname;
}
#undef CPUID_EXTFAMILY
#undef CPUID_EXTMODEL
#undef CPUID_TYPE
#undef CPUID_FAMILY
#undef CPUID_MODEL
#undef CPUID_STEPPING
#if defined(__linux__) && defined(_POSIX_SOURCE) && !defined(ARCH_X86_64)
static void sigill_handler_sse( int signal, struct sigcontext sc )
{
mp_msg(MSGT_CPUDETECT,MSGL_V, "SIGILL, " );
/* Both the "xorps %%xmm0,%%xmm0" and "divps %xmm0,%%xmm1"
* instructions are 3 bytes long. We must increment the instruction
* pointer manually to avoid repeated execution of the offending
* instruction.
*
* If the SIGILL is caused by a divide-by-zero when unmasked
* exceptions aren't supported, the SIMD FPU status and control
* word will be restored at the end of the test, so we don't need
* to worry about doing it here. Besides, we may not be able to...
*/
sc.eip += 3;
gCpuCaps.hasSSE=0;
}
#endif /* __linux__ && _POSIX_SOURCE */
#ifdef WIN32
LONG CALLBACK win32_sig_handler_sse(EXCEPTION_POINTERS* ep)
{
if(ep->ExceptionRecord->ExceptionCode==EXCEPTION_ILLEGAL_INSTRUCTION){
mp_msg(MSGT_CPUDETECT,MSGL_V, "SIGILL, " );
ep->ContextRecord->Eip +=3;
gCpuCaps.hasSSE=0;
return EXCEPTION_CONTINUE_EXECUTION;
}
return EXCEPTION_CONTINUE_SEARCH;
}
#endif /* WIN32 */
#ifdef __OS2__
ULONG _System os2_sig_handler_sse( PEXCEPTIONREPORTRECORD p1,
PEXCEPTIONREGISTRATIONRECORD p2,
PCONTEXTRECORD p3,
PVOID p4 )
{
if(p1->ExceptionNum == XCPT_ILLEGAL_INSTRUCTION){
mp_msg(MSGT_CPUDETECT, MSGL_V, "SIGILL, ");
p3->ctx_RegEip += 3;
gCpuCaps.hasSSE = 0;
return XCPT_CONTINUE_EXECUTION;
}
return XCPT_CONTINUE_SEARCH;
}
#endif
/* If we're running on a processor that can do SSE, let's see if we
* are allowed to or not. This will catch 2.4.0 or later kernels that
* haven't been configured for a Pentium III but are running on one,
* and RedHat patched 2.2 kernels that have broken exception handling
* support for user space apps that do SSE.
*/
#if defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || defined(__DragonFly__)
#define SSE_SYSCTL_NAME "hw.instruction_sse"
#elif defined(__APPLE__)
#define SSE_SYSCTL_NAME "hw.optional.sse"
#endif
static void check_os_katmai_support( void )
{
#ifdef ARCH_X86_64
gCpuCaps.hasSSE=1;
gCpuCaps.hasSSE2=1;
#elif defined(__FreeBSD__) || defined(__FreeBSD_kernel__) || defined(__DragonFly__) || defined(__APPLE__)
int has_sse=0, ret;
size_t len=sizeof(has_sse);
ret = sysctlbyname(SSE_SYSCTL_NAME, &has_sse, &len, NULL, 0);
if (ret || !has_sse)
gCpuCaps.hasSSE=0;
#elif defined(__NetBSD__) || defined (__OpenBSD__)
#if __NetBSD_Version__ >= 105250000 || (defined __OpenBSD__)
int has_sse, has_sse2, ret, mib[2];
size_t varlen;
mib[0] = CTL_MACHDEP;
mib[1] = CPU_SSE;
varlen = sizeof(has_sse);
mp_msg(MSGT_CPUDETECT,MSGL_V, "Testing OS support for SSE... " );
ret = sysctl(mib, 2, &has_sse, &varlen, NULL, 0);
if (ret < 0 || !has_sse) {
gCpuCaps.hasSSE=0;
mp_msg(MSGT_CPUDETECT,MSGL_V, "no!\n" );
} else {
gCpuCaps.hasSSE=1;
mp_msg(MSGT_CPUDETECT,MSGL_V, "yes!\n" );
}
mib[1] = CPU_SSE2;
varlen = sizeof(has_sse2);
mp_msg(MSGT_CPUDETECT,MSGL_V, "Testing OS support for SSE2... " );
ret = sysctl(mib, 2, &has_sse2, &varlen, NULL, 0);
if (ret < 0 || !has_sse2) {
gCpuCaps.hasSSE2=0;
mp_msg(MSGT_CPUDETECT,MSGL_V, "no!\n" );
} else {
gCpuCaps.hasSSE2=1;
mp_msg(MSGT_CPUDETECT,MSGL_V, "yes!\n" );
}
#else
gCpuCaps.hasSSE = 0;
mp_msg(MSGT_CPUDETECT,MSGL_WARN, "No OS support for SSE, disabling to be safe.\n" );
#endif
#elif defined(WIN32)
LPTOP_LEVEL_EXCEPTION_FILTER exc_fil;
if ( gCpuCaps.hasSSE ) {
mp_msg(MSGT_CPUDETECT,MSGL_V, "Testing OS support for SSE... " );
exc_fil = SetUnhandledExceptionFilter(win32_sig_handler_sse);
__asm __volatile ("xorps %xmm0, %xmm0");
SetUnhandledExceptionFilter(exc_fil);
if ( gCpuCaps.hasSSE ) mp_msg(MSGT_CPUDETECT,MSGL_V, "yes.\n" );
else mp_msg(MSGT_CPUDETECT,MSGL_V, "no!\n" );
}
#elif defined(__OS2__)
EXCEPTIONREGISTRATIONRECORD RegRec = { 0, &os2_sig_handler_sse };
if ( gCpuCaps.hasSSE ) {
mp_msg(MSGT_CPUDETECT,MSGL_V, "Testing OS support for SSE... " );
DosSetExceptionHandler( &RegRec );
__asm __volatile ("xorps %xmm0, %xmm0");
DosUnsetExceptionHandler( &RegRec );
if ( gCpuCaps.hasSSE ) mp_msg(MSGT_CPUDETECT,MSGL_V, "yes.\n" );
else mp_msg(MSGT_CPUDETECT,MSGL_V, "no!\n" );
}
#elif defined(__linux__)
#if defined(_POSIX_SOURCE)
struct sigaction saved_sigill;
/* Save the original signal handlers.
*/
sigaction( SIGILL, NULL, &saved_sigill );
signal( SIGILL, (void (*)(int))sigill_handler_sse );
/* Emulate test for OSFXSR in CR4. The OS will set this bit if it
* supports the extended FPU save and restore required for SSE. If
* we execute an SSE instruction on a PIII and get a SIGILL, the OS
* doesn't support Streaming SIMD Exceptions, even if the processor
* does.
*/
if ( gCpuCaps.hasSSE ) {
mp_msg(MSGT_CPUDETECT,MSGL_V, "Testing OS support for SSE... " );
// __asm __volatile ("xorps %%xmm0, %%xmm0");
__asm __volatile ("xorps %xmm0, %xmm0");
if ( gCpuCaps.hasSSE ) {
mp_msg(MSGT_CPUDETECT,MSGL_V, "yes.\n" );
} else {
mp_msg(MSGT_CPUDETECT,MSGL_V, "no!\n" );
}
}
/* Restore the original signal handlers.
*/
sigaction( SIGILL, &saved_sigill, NULL );
/* If we've gotten to here and the XMM CPUID bit is still set, we're
* safe to go ahead and hook out the SSE code throughout Mesa.
*/
if ( gCpuCaps.hasSSE ) {
mp_msg(MSGT_CPUDETECT,MSGL_V, "Tests of OS support for SSE passed.\n" );
} else {
mp_msg(MSGT_CPUDETECT,MSGL_V, "Tests of OS support for SSE failed!\n" );
}
#else
/* We can't use POSIX signal handling to test the availability of
* SSE, so we disable it by default.
*/
mp_msg(MSGT_CPUDETECT,MSGL_WARN, "Cannot test OS support for SSE, disabling to be safe.\n" );
gCpuCaps.hasSSE=0;
#endif /* _POSIX_SOURCE */
#else
/* Do nothing on other platforms for now.
*/
mp_msg(MSGT_CPUDETECT,MSGL_WARN, "Cannot test OS support for SSE, leaving disabled.\n" );
gCpuCaps.hasSSE=0;
#endif /* __linux__ */
}
#else /* ARCH_X86 */
#ifdef __APPLE__
#include <sys/sysctl.h>
#elif __AMIGAOS4__
/* nothing */
#else
#include <signal.h>
#include <setjmp.h>
static sigjmp_buf jmpbuf;
static volatile sig_atomic_t canjump = 0;
static void sigill_handler (int sig)
{
if (!canjump) {
signal (sig, SIG_DFL);
raise (sig);
}
canjump = 0;
siglongjmp (jmpbuf, 1);
}
#endif /* __APPLE__ */
void GetCpuCaps( CpuCaps *caps)
{
caps->cpuType=0;
caps->cpuModel=0;
caps->cpuStepping=0;
caps->hasMMX=0;
caps->hasMMX2=0;
caps->has3DNow=0;
caps->has3DNowExt=0;
caps->hasSSE=0;
caps->hasSSE2=0;
caps->isX86=0;
caps->hasAltiVec = 0;
#ifdef HAVE_ALTIVEC
#ifdef __APPLE__
/*
rip-off from ffmpeg altivec detection code.
this code also appears on Apple's AltiVec pages.
*/
{
int sels[2] = {CTL_HW, HW_VECTORUNIT};
int has_vu = 0;
size_t len = sizeof(has_vu);
int err;
err = sysctl(sels, 2, &has_vu, &len, NULL, 0);
if (err == 0)
if (has_vu != 0)
caps->hasAltiVec = 1;
}
#elif __AMIGAOS4__
ULONG result = 0;
GetCPUInfoTags(GCIT_VectorUnit, &result, TAG_DONE);
if (result == VECTORTYPE_ALTIVEC)
caps->hasAltiVec = 1;
#else
/* no Darwin, do it the brute-force way */
/* this is borrowed from the libmpeg2 library */
{
signal (SIGILL, sigill_handler);
if (sigsetjmp (jmpbuf, 1)) {
signal (SIGILL, SIG_DFL);
} else {
canjump = 1;
asm volatile ("mtspr 256, %0\n\t"
"vand %%v0, %%v0, %%v0"
:
: "r" (-1));
signal (SIGILL, SIG_DFL);
caps->hasAltiVec = 1;
}
}
#endif /* __APPLE__ */
mp_msg(MSGT_CPUDETECT,MSGL_INFO,"AltiVec %sfound\n", (caps->hasAltiVec ? "" : "not "));
#endif /* HAVE_ALTIVEC */
#ifdef ARCH_IA64
mp_msg(MSGT_CPUDETECT,MSGL_INFO,"CPU: Intel Itanium\n");
#endif
#ifdef ARCH_SPARC
mp_msg(MSGT_CPUDETECT,MSGL_INFO,"CPU: Sun Sparc\n");
#endif
#ifdef ARCH_ARMV4L
mp_msg(MSGT_CPUDETECT,MSGL_INFO,"CPU: ARM\n");
#endif
#ifdef ARCH_POWERPC
mp_msg(MSGT_CPUDETECT,MSGL_INFO,"CPU: PowerPC\n");
#endif
#ifdef ARCH_ALPHA
mp_msg(MSGT_CPUDETECT,MSGL_INFO,"CPU: Digital Alpha\n");
#endif
#ifdef ARCH_SGI_MIPS
mp_msg(MSGT_CPUDETECT,MSGL_INFO,"CPU: SGI MIPS\n");
#endif
#ifdef ARCH_PA_RISC
mp_msg(MSGT_CPUDETECT,MSGL_INFO,"CPU: Hewlett-Packard PA-RISC\n");
#endif
#ifdef ARCH_S390
mp_msg(MSGT_CPUDETECT,MSGL_INFO,"CPU: IBM S/390\n");
#endif
#ifdef ARCH_S390X
mp_msg(MSGT_CPUDETECT,MSGL_INFO,"CPU: IBM S/390X\n");
#endif
#ifdef ARCH_VAX
mp_msg(MSGT_CPUDETECT,MSGL_INFO, "CPU: Digital VAX\n" );
#endif
#ifdef ARCH_XTENSA
mp_msg(MSGT_CPUDETECT,MSGL_INFO, "CPU: Tensilica Xtensa\n" );
#endif
}
#endif /* !ARCH_X86 */
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