This introduces support for width%4==2 in addition to width%4==0. For
odd widths, some more checks are needed, since the current code always
handles two luma items in a row, thus there is a possibility of an
overread by one.

Signed-off-by: Martin Storsjö <martin@martin.st>

Signed-off-by: Diego Biurrun <diego@biurrun.de>

Signed-off-by: Martin Storsjö <martin@martin.st>

To access data at multiple fixed offsets from a base address, this
code uses a single "m" operand and code of the form "32%0", relying on
the memory operand instantiation having no displacement, giving a final
result of the form "32(%rax)".  If the compiler uses a register and
displacement, e.g. "64(%rax)", the end result becomes "3264(%rax)",
which obviously does not work.

Replacing the "m" operands with "r" operands allows safe addition of a
displacement.  In theory, multiple memory operands could use a shared
base register with different index registers, "(%rax,%rbx)", potentially
making more efficient use of registers.  In the cases at hand, no such
sharing is possible since the addresses involved are entirely unrelated.

After this change, the code somewhat rudely accesses memory without
using a corresponding memory operand, which in some cases can lead to
unwanted "optimisations" of surrounding code.  However, the original
code also accesses memory not covered by a memory operand, so this is
not adding any defect not already present.  It is also hightly unlikely
that any such optimisations could be performed here since the memory
locations in questions are not accessed elsewhere in the same functions.

This fixes crashes with suncc.
Signed-off-by: Mans Rullgard <mans@mansr.com>

This code has been disabled since 2003.  Nobody will ever look at
it again.
Signed-off-by: Mans Rullgard <mans@mansr.com>

This puts x86-specific things in the x86/ subdirectory where they
belong.
Signed-off-by: Mans Rullgard <mans@mansr.com>

Refactoring mmx2/mmxext YASM code with cpuflags will force renames.
So switching to a consistent naming scheme beforehand is sensible.
The name "mmxext" is more official and widespread and also the name
of the CPU flag, as reported e.g. by the Linux kernel.

The function called in this block is under HAVE_INLINE_ASM itself also.

The files do not contain only MMX code.

Fixes compilation for compilers that do not support gcc inline assembly.
Signed-off-by: Diego Biurrun <diego@biurrun.de>

Signed-off-by: Ronald S. Bultje <rsbultje@gmail.com>

Signed-off-by: Mans Rullgard <mans@mansr.com>

Signed-off-by: Mans Rullgard <mans@mansr.com>

Fixes bug 282.
Signed-off-by: Anton Khirnov <anton@khirnov.net>

If coefficient A is 12-bits xixed-point number "X", then the other
coefficient is (1 << 12) - X, not (1 << 12) - X - 1.

Fixes bug 270.

Also adjust some comments including wording and typo fixes.

Add support for all x86-64 registers
Prefer caller-saved register over callee-saved on WIN64
Support up to 15 function arguments

Also (by Ronald S. Bultje)
Fix up our asm to work with new x86inc.asm.
Signed-off-by: Ronald S. Bultje <rsbultje@gmail.com>
Signed-off-by: Justin Ruggles <justin.ruggles@gmail.com>

Fixes bug 269.

Signed-off-by: Michael Niedermayer <michaelni@gmx.at>
Signed-off-by: Derek Buitenhuis <derek.buitenhuis@gmail.com>

This allows simplifying the Makefiles; it is no longer necessary to register
arch subdirectory Makefiles, just putting them in place is enough.

Fixes bug 240, as well as several integer overflows (visible as glitches)
in other scaling output routines, e.g. YUV422.

Fixes overflows for large image sizes.

Found-by: Mateusz "j00ru" Jurczyk and Gynvael Coldwind
CC: libav-stable@libav.org