The Tor Browser / file revision

 /*

  * Copyright © 2000 SuSE, Inc.

  * Copyright © 2007 Red Hat, Inc.

  *

  * Permission to use, copy, modify, distribute, and sell this software and its

  * documentation for any purpose is hereby granted without fee, provided that

  * the above copyright notice appear in all copies and that both that

  * copyright notice and this permission notice appear in supporting

  * documentation, and that the name of SuSE not be used in advertising or

  * publicity pertaining to distribution of the software without specific,

  * written prior permission.  SuSE makes no representations about the

  * suitability of this software for any purpose.  It is provided "as is"

  * without express or implied warranty.

  *

  * SuSE DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING ALL

  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL SuSE

  * BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES

  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION

  * OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN

  * CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.

  */

 #ifdef HAVE_CONFIG_H

 #include <config.h>

 #endif

 #include <string.h>

 #include <stdlib.h>

 #if defined(USE_ARM_SIMD) && defined(_MSC_VER)

 /* Needed for EXCEPTION_ILLEGAL_INSTRUCTION */

 #include <windows.h>

 #endif

 #if defined(__APPLE__)

 #include "TargetConditionals.h"

 #endif

 #include "pixman-private.h"

 #ifdef USE_VMX

 /* The CPU detection code needs to be in a file not compiled with

  * "-maltivec -mabi=altivec", as gcc would try to save vector register

  * across function calls causing SIGILL on cpus without Altivec/vmx.

  */

 static pixman_bool_t initialized = FALSE;

 static volatile pixman_bool_t have_vmx = TRUE;

 #ifdef __APPLE__

 #include <sys/sysctl.h>

 static pixman_bool_t

 pixman_have_vmx (void)

 {

     if (!initialized)

     {

 	size_t length = sizeof(have_vmx);

 	int error =

 	    sysctlbyname ("hw.optional.altivec", &have_vmx, &length, NULL, 0);

 	if (error)

 	    have_vmx = FALSE;

 	initialized = TRUE;

     }

     return have_vmx;

 }

 #elif defined (__OpenBSD__)

 #include <sys/param.h>

 #include <sys/sysctl.h>

 #include <machine/cpu.h>

 static pixman_bool_t

 pixman_have_vmx (void)

 {

     if (!initialized)

     {

 	int mib[2] = { CTL_MACHDEP, CPU_ALTIVEC };

 	size_t length = sizeof(have_vmx);

 	int error =

 	    sysctl (mib, 2, &have_vmx, &length, NULL, 0);

 	if (error != 0)

 	    have_vmx = FALSE;

 	initialized = TRUE;

     }

     return have_vmx;

 }

 #elif defined (__linux__)

 #include <sys/types.h>

 #include <sys/stat.h>

 #include <fcntl.h>

 #include <unistd.h>

 #include <stdio.h>

 #include <linux/auxvec.h>

 #include <asm/cputable.h>

 static pixman_bool_t

 pixman_have_vmx (void)

 {

     if (!initialized)

     {

 	char fname[64];

 	unsigned long buf[64];

 	ssize_t count = 0;

 	pid_t pid;

 	int fd, i;

 	pid = getpid ();

 	snprintf (fname, sizeof(fname) - 1, "/proc/%d/auxv", pid);

 	fd = open (fname, O_RDONLY);

 	if (fd >= 0)

 	{

 	    for (i = 0; i <= (count / sizeof(unsigned long)); i += 2)

 	    {

 		/* Read more if buf is empty... */

 		if (i == (count / sizeof(unsigned long)))

 		{

 		    count = read (fd, buf, sizeof(buf));

 		    if (count <= 0)

 			break;

 		    i = 0;

 		}

 		if (buf[i] == AT_HWCAP)

 		{

 		    have_vmx = !!(buf[i + 1] & PPC_FEATURE_HAS_ALTIVEC);

 		    initialized = TRUE;

 		    break;

 		}

 		else if (buf[i] == AT_NULL)

 		{

 		    break;

 		}

 	    }

 	    close (fd);

 	}

     }

     if (!initialized)

     {

 	/* Something went wrong. Assume 'no' rather than playing

 	   fragile tricks with catching SIGILL. */

 	have_vmx = FALSE;

 	initialized = TRUE;

     }

     return have_vmx;

 }

 #else /* !__APPLE__ && !__OpenBSD__ && !__linux__ */

 #include <signal.h>

 #include <setjmp.h>

 static jmp_buf jump_env;

 static void

 vmx_test (int        sig,

 	  siginfo_t *si,

 	  void *     unused)

 {

     longjmp (jump_env, 1);

 }

 static pixman_bool_t

 pixman_have_vmx (void)

 {

     struct sigaction sa, osa;

     int jmp_result;

     if (!initialized)

     {

 	sa.sa_flags = SA_SIGINFO;

 	sigemptyset (&sa.sa_mask);

 	sa.sa_sigaction = vmx_test;

 	sigaction (SIGILL, &sa, &osa);

 	jmp_result = setjmp (jump_env);

 	if (jmp_result == 0)

 	{

 	    asm volatile ( "vor 0, 0, 0" );

 	}

 	sigaction (SIGILL, &osa, NULL);

 	have_vmx = (jmp_result == 0);

 	initialized = TRUE;

     }

     return have_vmx;

 }

 #endif /* __APPLE__ */

 #endif /* USE_VMX */

 #if defined(USE_ARM_SIMD) || defined(USE_ARM_NEON) || defined(USE_ARM_IWMMXT)

 #if defined(_MSC_VER)

 #if defined(USE_ARM_SIMD)

 extern int pixman_msvc_try_arm_simd_op ();

 pixman_bool_t

 pixman_have_arm_simd (void)

 {

     static pixman_bool_t initialized = FALSE;

     static pixman_bool_t have_arm_simd = FALSE;

     if (!initialized)

     {

 	__try {

 	    pixman_msvc_try_arm_simd_op ();

 	    have_arm_simd = TRUE;

 	} __except (GetExceptionCode () == EXCEPTION_ILLEGAL_INSTRUCTION) {

 	    have_arm_simd = FALSE;

 	}

 	initialized = TRUE;

     }

     return have_arm_simd;

 }

 #endif /* USE_ARM_SIMD */

 #if defined(USE_ARM_NEON)

 extern int pixman_msvc_try_arm_neon_op ();

 pixman_bool_t

 pixman_have_arm_neon (void)

 {

     static pixman_bool_t initialized = FALSE;

     static pixman_bool_t have_arm_neon = FALSE;

     if (!initialized)

     {

 	__try

 	{

 	    pixman_msvc_try_arm_neon_op ();

 	    have_arm_neon = TRUE;

 	}

 	__except (GetExceptionCode () == EXCEPTION_ILLEGAL_INSTRUCTION)

 	{

 	    have_arm_neon = FALSE;

 	}

 	initialized = TRUE;

     }

     return have_arm_neon;

 }

 #endif /* USE_ARM_NEON */

 #elif (defined (__APPLE__) && defined(TARGET_OS_IPHONE)) /* iOS (iPhone/iPad/iPod touch) */

 /* Detection of ARM NEON on iOS is fairly simple because iOS binaries

  * contain separate executable images for each processor architecture.

  * So all we have to do is detect the armv7 architecture build. The

  * operating system automatically runs the armv7 binary for armv7 devices

  * and the armv6 binary for armv6 devices.

  */

 pixman_bool_t

 pixman_have_arm_simd (void)

 {

 #if defined(USE_ARM_SIMD)

     return TRUE;

 #else

     return FALSE;

 #endif

 }

 pixman_bool_t

 pixman_have_arm_neon (void)

 {

 #if defined(USE_ARM_NEON) && defined(__ARM_NEON__)

     /* This is an armv7 cpu build */

     return TRUE;

 #else

     /* This is an armv6 cpu build */

     return FALSE;

 #endif

 }

 pixman_bool_t

 pixman_have_arm_iwmmxt (void)

 {

 #if defined(USE_ARM_IWMMXT)

     return FALSE;

 #else

     return FALSE;

 #endif

 }

 #elif defined (__linux__) || defined(__ANDROID__) || defined(ANDROID) /* linux ELF or ANDROID */

 static pixman_bool_t arm_has_v7 = FALSE;

 static pixman_bool_t arm_has_v6 = FALSE;

 static pixman_bool_t arm_has_vfp = FALSE;

 static pixman_bool_t arm_has_neon = FALSE;

 static pixman_bool_t arm_has_iwmmxt = FALSE;

 static pixman_bool_t arm_tests_initialized = FALSE;

 #if defined(__ANDROID__) || defined(ANDROID) /* Android device support */

 static void

 pixman_arm_read_auxv_or_cpu_features ()

 {

     char buf[1024];

     char* pos;

     const char* ver_token = "CPU architecture: ";

     FILE* f = fopen("/proc/cpuinfo", "r");

     if (!f) {

 	arm_tests_initialized = TRUE;

 	return;

     }

     fread(buf, sizeof(char), sizeof(buf), f);

     fclose(f);

     pos = strstr(buf, ver_token);

     if (pos) {

 	char vchar = *(pos + strlen(ver_token));

 	if (vchar >= '0' && vchar <= '9') {

 	    int ver = vchar - '0';

 	    arm_has_v7 = ver >= 7;

 	    arm_has_v6 = ver >= 6;

 	}

     }

     arm_has_neon = strstr(buf, "neon") != NULL;

     arm_has_vfp = strstr(buf, "vfp") != NULL;

     arm_has_iwmmxt = strstr(buf, "iwmmxt") != NULL;

     arm_tests_initialized = TRUE;

 }

 #elif defined (__linux__) /* linux ELF */

 #include <unistd.h>

 #include <sys/types.h>

 #include <sys/stat.h>

 #include <sys/mman.h>

 #include <fcntl.h>

 #include <string.h>

 #include <elf.h>

 static void

 pixman_arm_read_auxv_or_cpu_features ()

 {

     int fd;

     Elf32_auxv_t aux;

     fd = open ("/proc/self/auxv", O_RDONLY);

     if (fd >= 0)

     {

 	while (read (fd, &aux, sizeof(Elf32_auxv_t)) == sizeof(Elf32_auxv_t))

 	{

 	    if (aux.a_type == AT_HWCAP)

 	    {

 		uint32_t hwcap = aux.a_un.a_val;

 		/* hardcode these values to avoid depending on specific

 		 * versions of the hwcap header, e.g. HWCAP_NEON

 		 */

 		arm_has_vfp = (hwcap & 64) != 0;

 		arm_has_iwmmxt = (hwcap & 512) != 0;

 		/* this flag is only present on kernel 2.6.29 */

 		arm_has_neon = (hwcap & 4096) != 0;

 	    }

 	    else if (aux.a_type == AT_PLATFORM)

 	    {

 		const char *plat = (const char*) aux.a_un.a_val;

 		if (strncmp (plat, "v7l", 3) == 0)

 		{

 		    arm_has_v7 = TRUE;

 		    arm_has_v6 = TRUE;

 		}

 		else if (strncmp (plat, "v6l", 3) == 0)

 		{

 		    arm_has_v6 = TRUE;

 		}

 	    }

 	}

 	close (fd);

     }

     arm_tests_initialized = TRUE;

 }

 #endif /* Linux elf */

 #if defined(USE_ARM_SIMD)

 pixman_bool_t

 pixman_have_arm_simd (void)

 {

     if (!arm_tests_initialized)

 	pixman_arm_read_auxv_or_cpu_features ();

     return arm_has_v6;

 }

 #endif /* USE_ARM_SIMD */

 #if defined(USE_ARM_NEON)

 pixman_bool_t

 pixman_have_arm_neon (void)

 {

     if (!arm_tests_initialized)

 	pixman_arm_read_auxv_or_cpu_features ();

     return arm_has_neon;

 }

 #endif /* USE_ARM_NEON */

 #if defined(USE_ARM_IWMMXT)

 pixman_bool_t

 pixman_have_arm_iwmmxt (void)

 {

     if (!arm_tests_initialized)

 	pixman_arm_read_auxv_or_cpu_features ();

     return arm_has_iwmmxt;

 }

 #endif /* USE_ARM_IWMMXT */

 #else /* !_MSC_VER && !Linux elf && !Android */

 #define pixman_have_arm_simd() FALSE

 #define pixman_have_arm_neon() FALSE

 #define pixman_have_arm_iwmmxt() FALSE

 #endif

 #endif /* USE_ARM_SIMD || USE_ARM_NEON || USE_ARM_IWMMXT */

 #if defined(USE_MIPS_DSPR2)

 #if defined (__linux__) /* linux ELF */

 pixman_bool_t

 pixman_have_mips_dspr2 (void)

 {

     const char *search_string = "MIPS 74K";

     const char *file_name = "/proc/cpuinfo";

     /* Simple detection of MIPS DSP ASE (revision 2) at runtime for Linux.

      * It is based on /proc/cpuinfo, which reveals hardware configuration

      * to user-space applications.  According to MIPS (early 2010), no similar

      * facility is universally available on the MIPS architectures, so it's up

      * to individual OSes to provide such.

      *

      * Only currently available MIPS core that supports DSPr2 is 74K.

      */

     char cpuinfo_line[256];

     FILE *f = NULL;

     if ((f = fopen (file_name, "r")) == NULL)

         return FALSE;

     while (fgets (cpuinfo_line, sizeof (cpuinfo_line), f) != NULL)

     {

         if (strstr (cpuinfo_line, search_string) != NULL)

         {

             fclose (f);

             return TRUE;

         }

     }

     fclose (f);

     /* Did not find string in the proc file. */

     return FALSE;

 }

 #else /* linux ELF */

 #define pixman_have_mips_dspr2() FALSE

 #endif /* linux ELF */

 #endif /* USE_MIPS_DSPR2 */

 #if defined(USE_X86_MMX) || defined(USE_SSE2)

 /* The CPU detection code needs to be in a file not compiled with

  * "-mmmx -msse", as gcc would generate CMOV instructions otherwise

  * that would lead to SIGILL instructions on old CPUs that don't have

  * it.

  */

 #if !defined(__amd64__) && !defined(__x86_64__) && !defined(_M_AMD64)

 #ifdef HAVE_GETISAX

 #include <sys/auxv.h>

 #endif

 typedef enum

 {

     NO_FEATURES = 0,

     MMX = 0x1,

     MMX_EXTENSIONS = 0x2,

     SSE = 0x6,

     SSE2 = 0x8,

     CMOV = 0x10

 } cpu_features_t;

 static unsigned int

 detect_cpu_features (void)

 {

     unsigned int features = 0;

     unsigned int result = 0;

 #ifdef HAVE_GETISAX

     if (getisax (&result, 1))

     {

 	if (result & AV_386_CMOV)

 	    features |= CMOV;

 	if (result & AV_386_MMX)

 	    features |= MMX;

 	if (result & AV_386_AMD_MMX)

 	    features |= MMX_EXTENSIONS;

 	if (result & AV_386_SSE)

 	    features |= SSE;

 	if (result & AV_386_SSE2)

 	    features |= SSE2;

     }

 #else

     char vendor[13];

 #ifdef _MSC_VER

     int vendor0 = 0, vendor1, vendor2;

 #endif

     vendor[0] = 0;

     vendor[12] = 0;

 #ifdef __GNUC__

     /* see p. 118 of amd64 instruction set manual Vol3 */

     /* We need to be careful about the handling of %ebx and

      * %esp here. We can't declare either one as clobbered

      * since they are special registers (%ebx is the "PIC

      * register" holding an offset to global data, %esp the

      * stack pointer), so we need to make sure they have their

      * original values when we access the output operands.

      */

     __asm__ (

         "pushf\n"

         "pop %%eax\n"

         "mov %%eax, %%ecx\n"

         "xor $0x00200000, %%eax\n"

         "push %%eax\n"

         "popf\n"

         "pushf\n"

         "pop %%eax\n"

         "mov $0x0, %%edx\n"

         "xor %%ecx, %%eax\n"

         "jz 1f\n"

         "mov $0x00000000, %%eax\n"

         "push %%ebx\n"

         "cpuid\n"

         "mov %%ebx, %%eax\n"

         "pop %%ebx\n"

         "mov %%eax, %1\n"

         "mov %%edx, %2\n"

         "mov %%ecx, %3\n"

         "mov $0x00000001, %%eax\n"

         "push %%ebx\n"

         "cpuid\n"

         "pop %%ebx\n"

         "1:\n"

         "mov %%edx, %0\n"

 	: "=r" (result),

         "=m" (vendor[0]),

         "=m" (vendor[4]),

         "=m" (vendor[8])

 	:

 	: "%eax", "%ecx", "%edx"

         );

 #elif defined (_MSC_VER)

     _asm {

 	pushfd

 	pop eax

 	mov ecx, eax

 	xor eax, 00200000h

 	push eax

 	popfd

 	pushfd

 	pop eax

 	mov edx, 0

 	xor eax, ecx

 	jz nocpuid

 	mov eax, 0

 	push ebx

 	cpuid

 	mov eax, ebx

 	pop ebx

 	mov vendor0, eax

 	mov vendor1, edx

 	mov vendor2, ecx

 	mov eax, 1

 	push ebx

 	cpuid

 	pop ebx

     nocpuid:

 	mov result, edx

     }

     memmove (vendor + 0, &vendor0, 4);

     memmove (vendor + 4, &vendor1, 4);

     memmove (vendor + 8, &vendor2, 4);

 #else

 #   error unsupported compiler

 #endif

     features = 0;

     if (result)

     {

 	/* result now contains the standard feature bits */

 	if (result & (1 << 15))

 	    features |= CMOV;

 	if (result & (1 << 23))

 	    features |= MMX;

 	if (result & (1 << 25))

 	    features |= SSE;

 	if (result & (1 << 26))

 	    features |= SSE2;

 	if ((features & MMX) && !(features & SSE) &&

 	    (strcmp (vendor, "AuthenticAMD") == 0 ||

 	     strcmp (vendor, "Geode by NSC") == 0))

 	{

 	    /* check for AMD MMX extensions */

 #ifdef __GNUC__

 	    __asm__ (

 	        "	push %%ebx\n"

 	        "	mov $0x80000000, %%eax\n"

 	        "	cpuid\n"

 	        "	xor %%edx, %%edx\n"

 	        "	cmp $0x1, %%eax\n"

 	        "	jge 2f\n"

 	        "	mov $0x80000001, %%eax\n"

 	        "	cpuid\n"

 	        "2:\n"

 	        "	pop %%ebx\n"

 	        "	mov %%edx, %0\n"

 		: "=r" (result)

 		:

 		: "%eax", "%ecx", "%edx"

 	        );

 #elif defined _MSC_VER

 	    _asm {

 		push ebx

 		mov eax, 80000000h

 		cpuid

 		xor edx, edx

 		cmp eax, 1

 		jge notamd

 		mov eax, 80000001h

 		cpuid

 	    notamd:

 		pop ebx

 		mov result, edx

 	    }

 #endif

 	    if (result & (1 << 22))

 		features |= MMX_EXTENSIONS;

 	}

     }

 #endif /* HAVE_GETISAX */

     return features;

 }

 #ifdef USE_X86_MMX

 static pixman_bool_t

 pixman_have_mmx (void)

 {

     static pixman_bool_t initialized = FALSE;

     static pixman_bool_t mmx_present;

     if (!initialized)

     {

 	unsigned int features = detect_cpu_features ();

 	mmx_present = (features & (MMX | MMX_EXTENSIONS)) == (MMX | MMX_EXTENSIONS);

 	initialized = TRUE;

     }

     return mmx_present;

 }

 #endif

 #ifdef USE_SSE2

 static pixman_bool_t

 pixman_have_sse2 (void)

 {

     static pixman_bool_t initialized = FALSE;

     static pixman_bool_t sse2_present;

     if (!initialized)

     {

 	unsigned int features = detect_cpu_features ();

 	sse2_present = (features & (MMX | MMX_EXTENSIONS | SSE | SSE2)) == (MMX | MMX_EXTENSIONS | SSE | SSE2);

 	initialized = TRUE;

     }

     return sse2_present;

 }

 #endif

 #else /* __amd64__ */

 #ifdef USE_X86_MMX

 #define pixman_have_mmx() TRUE

 #endif

 #ifdef USE_SSE2

 #define pixman_have_sse2() TRUE

 #endif

 #endif /* __amd64__ */

 #endif

 static pixman_bool_t

 disabled (const char *name)

 {

     const char *env;

     if ((env = getenv ("PIXMAN_DISABLE")))

     {

 	do

 	{

 	    const char *end;

 	    int len;

 	    if ((end = strchr (env, ' ')))

 		len = end - env;

 	    else

 		len = strlen (env);

 	    if (strlen (name) == len && strncmp (name, env, len) == 0)

 	    {

 		printf ("pixman: Disabled %s implementation\n", name);

 		return TRUE;

 	    }

 	    env += len;

 	}

 	while (*env++);

     }

     return FALSE;

 }

 pixman_implementation_t *

 _pixman_choose_implementation (void)

 {

     pixman_implementation_t *imp;

     imp = _pixman_implementation_create_general();

     if (!disabled ("fast"))

 	imp = _pixman_implementation_create_fast_path (imp);

 #ifdef USE_X86_MMX

     if (!disabled ("mmx") && pixman_have_mmx ())

 	imp = _pixman_implementation_create_mmx (imp);

 #endif

 #ifdef USE_SSE2

     if (!disabled ("sse2") && pixman_have_sse2 ())

 	imp = _pixman_implementation_create_sse2 (imp);

 #endif

 #ifdef USE_ARM_SIMD

     if (!disabled ("arm-simd") && pixman_have_arm_simd ())

 	imp = _pixman_implementation_create_arm_simd (imp);

 #endif

 #ifdef USE_ARM_IWMMXT

     if (!disabled ("arm-iwmmxt") && pixman_have_arm_iwmmxt ())

 	imp = _pixman_implementation_create_mmx (imp);

 #endif

 #ifdef USE_ARM_NEON

     if (!disabled ("arm-neon") && pixman_have_arm_neon ())

 	imp = _pixman_implementation_create_arm_neon (imp);

 #endif

 #ifdef USE_MIPS_DSPR2

     if (!disabled ("mips-dspr2") && pixman_have_mips_dspr2 ())

 	imp = _pixman_implementation_create_mips_dspr2 (imp);

 #endif

 #ifdef USE_VMX

     if (!disabled ("vmx") && pixman_have_vmx ())

 	imp = _pixman_implementation_create_vmx (imp);

 #endif

     imp = _pixman_implementation_create_noop (imp);

     return imp;

 }