avoid vectors for pnacl which cause linker failure.

avoid vectors for pnacl which cause linker failure.


R=sergeyu@chromium.org
BUG=chromium:538243
Committed: https://chromium.googlesource.com/libyuv/libyuv/+/c7c188379bb3698b734cbd4a8e5056fe893ad2a6

[Sergey Ulanov, 2015-10-13 00:10:54]

I don't think we need this. PNaCl toolchain supports vector_size() attribute, so
it should compile just fine. It's possible to workaround that issue by enabling
optimization and we don't need this second workaround.

[fbarchard, 2015-10-14 00:49:16]

On 2015/10/13 00:10:54, Sergey Ulanov wrote:
> I don't think we need this. PNaCl toolchain supports vector_size() attribute,
so
> it should compile just fine. It's possible to workaround that issue by
enabling
> optimization and we don't need this second workaround.

Theres 2 reasons for doing this change

1. the breakage is an unintentional regression.  Previously we used the C
definitions of these types
e.g. typedef uint8 uvec8[16];
a change for clangcl caused pnacl to switch to GCC style vectors, necessary for
inline SIMD.
typedef uint8 __attribute__((vector_size(16))) uvec8;

2. the fix so far is for GN only.
libyuv doesnt have GN builds yet, so we've used make files to test nacl.
fixing the code will work with any build system.

[Sergey Ulanov, 2015-10-14 21:06:25]

On 2015/10/14 00:49:16, fbarchard wrote:
> On 2015/10/13 00:10:54, Sergey Ulanov wrote:
> > I don't think we need this. PNaCl toolchain supports vector_size()
attribute,
> so
> > it should compile just fine. It's possible to workaround that issue by
> enabling
> > optimization and we don't need this second workaround.
> 
> Theres 2 reasons for doing this change
> 
> 1. the breakage is an unintentional regression.  Previously we used the C
> definitions of these types
> e.g. typedef uint8 uvec8[16];
> a change for clangcl caused pnacl to switch to GCC style vectors, necessary
for
> inline SIMD.
> typedef uint8 __attribute__((vector_size(16))) uvec8;
> 
> 2. the fix so far is for GN only.
> libyuv doesnt have GN builds yet, so we've used make files to test nacl.
> fixing the code will work with any build system.

FWIW in chromium PNaCl code is always compiled with -O2 when using GYP.
lgtm

[fbarchard1, 2015-10-14 21:49:55]

Committed patchset #1 (id:1) manually as
c7c188379bb3698b734cbd4a8e5056fe893ad2a6 (presubmit successful).