neon code for bgra to rgba conversion for copyFTBitmap

neon code for bgra to rgba conversion for copyFTBitmap

Tested with below:

android_run_skia gm --match coloremo --resourcePath /data/local/tmp -w /data/local/tmp --config 8888

<adb pull imag /data/local/tmp/8888/gm/coloremoji.png>

Compared output is same.

Measurement show improvement of 90%.

BUG=skia:

[frederic.ma, 2015-01-29 15:37:15]

frederic.ma@samsung.com changed reviewers:
+ bungeman@google.com

[frederic.ma, 2015-01-29 15:37:50]

Please review the patch

[reed1, 2015-01-29 15:47:19]

reed@google.com changed reviewers:
+ reed@google.com

[reed1, 2015-01-29 15:47:20]

https://codereview.chromium.org/892453002/diff/1/src/opts/SkFontHost_FreeType...
File src/opts/SkFontHost_FreeType_common_opts_neon.cpp (right):

https://codereview.chromium.org/892453002/diff/1/src/opts/SkFontHost_FreeType...
src/opts/SkFontHost_FreeType_common_opts_neon.cpp:3: void BGRA2RGBA_Neon(const
uint8_t* src, uint8_t* dst, size_t height, const size_t width, const size_t
dstRowBytes, const int srcPitch)
1. col max is 100
2. why is dst..rowBytes and src..Pitch? Skia convention is to use rowBytes

https://codereview.chromium.org/892453002/diff/1/src/opts/SkFontHost_FreeType...
File src/opts/SkFontHost_FreeType_common_opts_neon.h (right):

https://codereview.chromium.org/892453002/diff/1/src/opts/SkFontHost_FreeType...
src/opts/SkFontHost_FreeType_common_opts_neon.h:1: void BGRA2RGBA_Neon(const
uint8_t* src, uint8_t* dst, size_t height, const size_t width, const size_t
dstRowBytes, const int srcPitch);
Please document this call:
- why does it take bytes instead of uint32_t?
- skia's convention is to use "int" for counts such as width and height, and
only use size_t for byte counts
- skia's convention reserves "const" for only refs and pointers.

https://codereview.chromium.org/892453002/diff/1/src/ports/SkFontHost_FreeTyp...
File src/ports/SkFontHost_FreeType_common.cpp (right):

https://codereview.chromium.org/892453002/diff/1/src/ports/SkFontHost_FreeTyp...
src/ports/SkFontHost_FreeType_common.cpp:234: {
SkPMColor (which is the desired output swizzle) can be either BGRA or RGBA,
depending on compile flags, so we can't always call the new function. The
existing code calls a macro for packing, which always does the correct thing.

[bungeman-skia, 2015-01-29 15:47:41]

bungeman@google.com changed reviewers:
+ djsollen@google.com

[bungeman-skia, 2015-01-29 15:47:41]

I'm pretty sure this isn't a hot spot in real use.

[frederic.ma, 2015-01-29 15:49:53]

On 2015/01/29 15:47:41, bungeman1 wrote:
> I'm pretty sure this isn't a hot spot in real use.

It seems to be only used for emoji content afaict

[frederic.ma, 2015-01-29 18:33:09]

Thanks for the review.
Just updated.

https://codereview.chromium.org/892453002/diff/1/src/opts/SkFontHost_FreeType...
File src/opts/SkFontHost_FreeType_common_opts_neon.cpp (right):

https://codereview.chromium.org/892453002/diff/1/src/opts/SkFontHost_FreeType...
src/opts/SkFontHost_FreeType_common_opts_neon.cpp:3: void BGRA2RGBA_Neon(const
uint8_t* src, uint8_t* dst, size_t height, const size_t width, const size_t
dstRowBytes, const int srcPitch)
On 2015/01/29 15:47:19, reed1 wrote:
> 1. col max is 100
> 2. why is dst..rowBytes and src..Pitch? Skia convention is to use rowBytes

1. Col max fixed
2. dst..rowBytes and src..Pitch renamed.

https://codereview.chromium.org/892453002/diff/1/src/opts/SkFontHost_FreeType...
File src/opts/SkFontHost_FreeType_common_opts_neon.h (right):

https://codereview.chromium.org/892453002/diff/1/src/opts/SkFontHost_FreeType...
src/opts/SkFontHost_FreeType_common_opts_neon.h:1: void BGRA2RGBA_Neon(const
uint8_t* src, uint8_t* dst, size_t height, const size_t width, const size_t
dstRowBytes, const int srcPitch);
On 2015/01/29 15:47:20, reed1 wrote:
> Please document this call:
> - why does it take bytes instead of uint32_t?
> - skia's convention is to use "int" for counts such as width and height, and
> only use size_t for byte counts
> - skia's convention reserves "const" for only refs and pointers.

Done.

https://codereview.chromium.org/892453002/diff/1/src/ports/SkFontHost_FreeTyp...
File src/ports/SkFontHost_FreeType_common.cpp (right):

https://codereview.chromium.org/892453002/diff/1/src/ports/SkFontHost_FreeTyp...
src/ports/SkFontHost_FreeType_common.cpp:234: {
On 2015/01/29 15:47:20, reed1 wrote:
> SkPMColor (which is the desired output swizzle) can be either BGRA or RGBA,
> depending on compile flags, so we can't always call the new function. The
> existing code calls a macro for packing, which always does the correct thing.

My bad. I added compile flag to handle SkPMColor formats.