[file head]:
/* pnggccrd.c - mixed C/assembler version of utilities to read a PNG file
*
* For Intel x86 CPU (Pentium-MMX or later) and GNU C compiler.
*
* See http://www.intel.com/drg/pentiumII/appnotes/916/916.htm
* and http://www.intel.com/drg/pentiumII/appnotes/923/923.htm
* for Intel's performance analysis of the MMX vs. non-MMX code.
*
* libpng version 1.0.12 - June 8, 2001
* For conditions of distribution and use, see copyright notice in png.h
* Copyright (c) 1998-2001 Glenn Randers-Pehrson
* Copyright (c) 1998, Intel Corporation
*
* Based on MSVC code contributed by Nirav Chhatrapati, Intel Corp., 1998.
* Interface to libpng contributed by Gilles Vollant, 1999.
* GNU C port by Greg Roelofs, 1999-2001.
*
* Lines 2350-4300 converted in place with intel2gas 1.3.1:
*
* intel2gas -mdI pnggccrd.c.partially-msvc -o pnggccrd.c
*
* and then cleaned up by hand. See http://hermes.terminal.at/intel2gas/ .
*
* NOTE: A sufficiently recent vers
... ...

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... ...
o 0
".RETURN: \n\t" // target label for jump instructions
"movl >>eax, _mmx_supported \n\t" // save in global static variable, too
"popl >>edx \n\t" // restore edx
"popl >>ecx \n\t" // restore ecx
"popl >>ebx \n\t" // restore ebx

// "ret \n\t" // DONE: no MMX support
// (fall through to standard C "ret")

: // output list (none)

: // any variables used on input (none)

: ">eax" // clobber list
// , ">ebx", ">ecx", ">edx" // GRR: we handle these manually
// , "memory" // if write to a variable gcc thought was in a reg
// , "cc" // "condition codes" (flag bits)
);
#else
_mmx_supported = 0;
#endif /* PNG_MMX_CODE_SUPPORTED */

return _mmx_supported;
}

#endif /* PNG_USE_PNGGCCRD */