Bug 512865. qcms: Improve SSE2 performance, add SSE support. r=jrmuizel This patch greatly improves the performance of QCMS transformations on x86 & x86_64 systems. Some notes: 0. On 32-bit x86 systems it does runtime selection between non-SIMD, SSE, and SSE2 code paths. 1. On x86_64 systems the SSE2 code path is always taken. The non-SIMD and SSE code paths are left intact, but contemporary versions of the GCC and MSVC compilers will see that they cannot be reached and optimize them away. 2. The execution of the SSE2 code path is reduced by 67%, relative to the original Intel/Microsoft formatted ASM code. The relative performance is seen on a Pentium4 (Northwood) 2.4GHz CPU with DDR1 RAM. 3. The SSE code path provides a 80% reduction in execution time, relative to the non-SIMD code path. The relative performance is seen on a Pentium3 (Coppermine) 1.26GHz CPU with SDRAM. 4. The code has been split out into separate files so that it can be built with different cflags (-msse, and -msse2) when using gcc. 5. Try to land again, this time with __attribute__((__force_align_arg_pointer__)) to avoid crashes on linux.

/* The following defines are only used by the xpcom implementation */

#ifndef _XPCOM_PRIVATE_H_
#define _XPCOM_PRIVATE_H_

/* Define if getpagesize() is available */
#undef HAVE_GETPAGESIZE

/* Define if iconv() is available */
#undef HAVE_ICONV

/* Define if iconv() supports const input */
#undef HAVE_ICONV_WITH_CONST_INPUT

/* Define if mbrtowc() is available */
#undef HAVE_MBRTOWC

/* Define if <sys/mount.h> is present */
#undef HAVE_SYS_MOUNT_H

/* Define if <sys/vfs.h> is present */
#undef HAVE_SYS_VFS_H

/* Define if wcrtomb() is available */
#undef HAVE_WCRTOMB

#endif /* _XPCOM_PRIVATE_H_ */