Integrate premultiply/unpremultiply operations into libjpeg-turbo....

third_party/libjpeg_turbo/simd/jccolss2.asm

Index: third_party/libjpeg_turbo/simd/jccolss2.asm
===================================================================
--- third_party/libjpeg_turbo/simd/jccolss2.asm	(revision 69212)
+++ third_party/libjpeg_turbo/simd/jccolss2.asm	(working copy)
@@ -44,10 +44,12 @@
 PW_MF008_MF041	times 4 dw -F_0_081,-F_0_418
 PD_ONEHALFM1_CJ	times 4 dd  (1 << (SCALEBITS-1)) - 1 + (CENTERJSAMPLE << SCALEBITS)
 PD_ONEHALF	times 4 dd  (1 << (SCALEBITS-1))
+PF_255          times 4 dd 0x437f0000 ; 255.0f
 
 	alignz	16
 
 ; --------------------------------------------------------------------------
+%define PREMULTIPLY 0
 %include "jcclrss2.asm"
 
 %undef RGB_RED
@@ -58,6 +60,7 @@
 %define RGB_GREEN 1
 %define RGB_BLUE 2
 %define RGB_PIXELSIZE 3
+%define PREMULTIPLY 0
 %define jsimd_rgb_ycc_convert_sse2 jsimd_extrgb_ycc_convert_sse2
 %include "jcclrss2.asm"
 
@@ -115,3 +118,15 @@
 %define RGB_PIXELSIZE 4
 %define jsimd_rgb_ycc_convert_sse2 jsimd_extxrgb_ycc_convert_sse2
 %include "jcclrss2.asm"
+
+%define PREMULTIPLY 1
+%undef RGB_RED
+%undef RGB_GREEN
+%undef RGB_BLUE
+%undef RGB_PIXELSIZE
+%define RGB_RED 2
+%define RGB_GREEN 1
+%define RGB_BLUE 0
+%define RGB_PIXELSIZE 4
+%define jsimd_rgb_ycc_convert_sse2 jsimd_extbgra_ycc_convert_sse2
+%include "jcclrss2.asm"