1.1 --- /dev/null	Thu Jan 01 00:00:00 1970 +0000
     1.2 +++ b/libs/libpng/pnggccrd.c	Sun Nov 01 00:36:56 2015 +0200
     1.3 @@ -0,0 +1,103 @@
     1.4 +/* pnggccrd.c was removed from libpng-1.2.20. */
     1.5 +
     1.6 +/* This code snippet is for use by configure's compilation test. */
     1.7 +
     1.8 +#if (!defined _MSC_VER) && \
     1.9 +    defined(PNG_ASSEMBLER_CODE_SUPPORTED) && \
    1.10 +    defined(PNG_MMX_CODE_SUPPORTED)
    1.11 +
    1.12 +int PNGAPI png_dummy_mmx_support(void);
    1.13 +
    1.14 +static int _mmx_supported = 2; // 0: no MMX; 1: MMX supported; 2: not tested
    1.15 +
    1.16 +int PNGAPI
    1.17 +png_dummy_mmx_support(void) __attribute__((noinline));
    1.18 +
    1.19 +int PNGAPI
    1.20 +png_dummy_mmx_support(void)
    1.21 +{
    1.22 +   int result;
    1.23 +#if defined(PNG_MMX_CODE_SUPPORTED)  // superfluous, but what the heck
    1.24 +    __asm__ __volatile__ (
    1.25 +#if defined(__x86_64__)
    1.26 +        "pushq %%rbx          \n\t"  // rbx gets clobbered by CPUID instruction
    1.27 +        "pushq %%rcx          \n\t"  // so does rcx...
    1.28 +        "pushq %%rdx          \n\t"  // ...and rdx (but rcx & rdx safe on Linux)
    1.29 +        "pushfq               \n\t"  // save Eflag to stack
    1.30 +        "popq %%rax           \n\t"  // get Eflag from stack into rax
    1.31 +        "movq %%rax, %%rcx    \n\t"  // make another copy of Eflag in rcx
    1.32 +        "xorl $0x200000, %%eax \n\t" // toggle ID bit in Eflag (i.e., bit 21)
    1.33 +        "pushq %%rax          \n\t"  // save modified Eflag back to stack
    1.34 +        "popfq                \n\t"  // restore modified value to Eflag reg
    1.35 +        "pushfq               \n\t"  // save Eflag to stack
    1.36 +        "popq %%rax           \n\t"  // get Eflag from stack
    1.37 +        "pushq %%rcx          \n\t"  // save original Eflag to stack
    1.38 +        "popfq                \n\t"  // restore original Eflag
    1.39 +#else
    1.40 +        "pushl %%ebx          \n\t"  // ebx gets clobbered by CPUID instruction
    1.41 +        "pushl %%ecx          \n\t"  // so does ecx...
    1.42 +        "pushl %%edx          \n\t"  // ...and edx (but ecx & edx safe on Linux)
    1.43 +        "pushfl               \n\t"  // save Eflag to stack
    1.44 +        "popl %%eax           \n\t"  // get Eflag from stack into eax
    1.45 +        "movl %%eax, %%ecx    \n\t"  // make another copy of Eflag in ecx
    1.46 +        "xorl $0x200000, %%eax \n\t" // toggle ID bit in Eflag (i.e., bit 21)
    1.47 +        "pushl %%eax          \n\t"  // save modified Eflag back to stack
    1.48 +        "popfl                \n\t"  // restore modified value to Eflag reg
    1.49 +        "pushfl               \n\t"  // save Eflag to stack
    1.50 +        "popl %%eax           \n\t"  // get Eflag from stack
    1.51 +        "pushl %%ecx          \n\t"  // save original Eflag to stack
    1.52 +        "popfl                \n\t"  // restore original Eflag
    1.53 +#endif
    1.54 +        "xorl %%ecx, %%eax    \n\t"  // compare new Eflag with original Eflag
    1.55 +        "jz 0f                \n\t"  // if same, CPUID instr. is not supported
    1.56 +
    1.57 +        "xorl %%eax, %%eax    \n\t"  // set eax to zero
    1.58 +//      ".byte  0x0f, 0xa2    \n\t"  // CPUID instruction (two-byte opcode)
    1.59 +        "cpuid                \n\t"  // get the CPU identification info
    1.60 +        "cmpl $1, %%eax       \n\t"  // make sure eax return non-zero value
    1.61 +        "jl 0f                \n\t"  // if eax is zero, MMX is not supported
    1.62 +
    1.63 +        "xorl %%eax, %%eax    \n\t"  // set eax to zero and...
    1.64 +        "incl %%eax           \n\t"  // ...increment eax to 1.  This pair is
    1.65 +                                     // faster than the instruction "mov eax, 1"
    1.66 +        "cpuid                \n\t"  // get the CPU identification info again
    1.67 +        "andl $0x800000, %%edx \n\t" // mask out all bits but MMX bit (23)
    1.68 +        "cmpl $0, %%edx       \n\t"  // 0 = MMX not supported
    1.69 +        "jz 0f                \n\t"  // non-zero = yes, MMX IS supported
    1.70 +
    1.71 +        "movl $1, %%eax       \n\t"  // set return value to 1
    1.72 +        "jmp  1f              \n\t"  // DONE:  have MMX support
    1.73 +
    1.74 +    "0:                       \n\t"  // .NOT_SUPPORTED: target label for jump instructions
    1.75 +        "movl $0, %%eax       \n\t"  // set return value to 0
    1.76 +    "1:                       \n\t"  // .RETURN: target label for jump instructions
    1.77 +#if defined(__x86_64__)
    1.78 +        "popq %%rdx           \n\t"  // restore rdx
    1.79 +        "popq %%rcx           \n\t"  // restore rcx
    1.80 +        "popq %%rbx           \n\t"  // restore rbx
    1.81 +#else
    1.82 +        "popl %%edx           \n\t"  // restore edx
    1.83 +        "popl %%ecx           \n\t"  // restore ecx
    1.84 +        "popl %%ebx           \n\t"  // restore ebx
    1.85 +#endif
    1.86 +
    1.87 +//      "ret                  \n\t"  // DONE:  no MMX support
    1.88 +                                     // (fall through to standard C "ret")
    1.89 +
    1.90 +        : "=a" (result)              // output list
    1.91 +
    1.92 +        :                            // any variables used on input (none)
    1.93 +
    1.94 +                                     // no clobber list
    1.95 +//      , "%ebx", "%ecx", "%edx"     // GRR:  we handle these manually
    1.96 +//      , "memory"   // if write to a variable gcc thought was in a reg
    1.97 +//      , "cc"       // "condition codes" (flag bits)
    1.98 +    );
    1.99 +    _mmx_supported = result;
   1.100 +#else
   1.101 +    _mmx_supported = 0;
   1.102 +#endif /* PNG_MMX_CODE_SUPPORTED */
   1.103 +
   1.104 +    return _mmx_supported;
   1.105 +}
   1.106 +#endif