this moves the function outside the WEBP_USE_INTRINSICS check.
there's no alternative version and it's ~70% faster at the
function level and 1-2% faster overall
Change-Id: I59fb4918ec86b1ac3a47cbd5d05ce62f007461cb
generates a stub function when the specific architecture is not enabled,
exposing a symbol in the module, avoiding a compiler warning
Change-Id: Ia9336e57466a9b5241b85c1c95838e91c9283147
the standard vtbl functions are available there [1][2].
based on a patch from: aaroncrespo
fixes issue #243.
[1]
http://adcdownload.apple.com//Developer_Tools/Xcode_6.3_beta/Xcode_6.3_beta_Release_Notes.pdf
[2] Apple LLVM Compiler Version 6.1
- Xcode 6.3 updates the Apple LLVM compiler to version 6.1.0.
[...]
Support for the arm64 architecture has been significantly revised to
align with ARM's implementation, where the most visible impact is that a
few of the vector intrinsics have changed to match ARM's specifications.
Change-Id: I79a0016f44b9dbe36d0373f7f00a50ab3c2ca447
similar to:
1ba61b0 enable NEON intrinsics in aarch64 builds
vtbl1_u8 is available everywhere but Xcode-based iOS arm64 builds, use
vtbl1q_u8 there.
performance varies based on the input, 1-3% on encode was observed
Change-Id: Ifec35b37eb856acfcf69ed7f16fa078cd40b7034
move the attribute to the front of the function to quiet clang warning:
GCC does not allow no_sanitize_thread attribute in this position on a
function definition
Change-Id: Ie4cc6e35a07bd00eab67d9cd6801bd2be9cfe676
Verified OK, but right now they don't seem faster.
So they are disabled behind a USE_INTRINSICS flag (off for now)
Change-Id: I72a1c4fa3798f98c1e034f7ca781914c36d3392c
new file: lossless_neon.c
speedup is ~5%
gcc 4.6.3 seems to be doing some sub-optimal things here,
storing register on stack using 'vstmia' and such.
Looks similar to gcc.gnu.org/bugzilla/show_bug.cgi?id=51509
I've tried adding -fno-split-wide-types and it does help
the generated assembly. But the overall speed gets worse with
this flag. We should only compile lossless_neon.c with it -> urk.
Change-Id: I2ccc0929f5ef9dfb0105960e65c0b79b5f18d3b0
