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Implemented png_read_filter_up_vsx

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This commit is contained in:
Vadim Barkov 2017-01-15 20:20:29 +03:00
parent 6ff408d423
commit 91acd4baf8
1 changed files with 41 additions and 16 deletions
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57
powerpc/filter_vsx_intrinsics.c
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@ -18,18 +18,20 @@
/* This code requires -maltivec and -mabi=altivec on the command line: */
#if PNG_POWERPC_VSX_IMPLEMENTATION == 1 /* intrinsics code from pngpriv.h */
/* libpng row pointers are not necessarily aligned to any particular boundary,
* however this code will only work with appropriate alignment. arm/arm_init.c
* checks for this (and will not compile unless it is done). This code uses
* variants of png_aligncast to avoid compiler warnings.
*/
#define png_ptr(type,pointer) png_aligncast(type *,pointer)
#define png_ptrc(type,pointer) png_aligncastconst(const type *,pointer)
/*#include <altivec.h>*/
#include <altivec.h>
#if PNG_POWERPC_VSX_OPT > 0
/* Functions in this file look at most 3 pixels (a,b,c) to predict the 4th (d).
* They're positioned like this:
* prev: c b
* row: a d
* The Sub filter predicts d=a, Avg d=(a+b)/2, and Paeth predicts d to be
* whichever of a, b, or c is closest to p=a+b-c.
* ( this is taken from ../intel/filter_sse2_intrinsics.c )
*/
void png_read_filter_row_up_vsx(png_row_infop row_info, png_bytep row,
png_const_bytep prev_row)
{
@ -38,27 +40,50 @@ void png_read_filter_row_up_vsx(png_row_infop row_info, png_bytep row,
png_bytep rp = row;
png_const_bytep pp = prev_row;
for (i = 0; i < istop; i++)
vector unsigned char rp_vec;
vector unsigned char pp_vec;
/* Using SIMD while we can */
while( istop >= 16 )
{
*rp = (png_byte)(((int)(*rp) + (int)(*pp++)) & 0xff);
rp++;
rp_vec = vec_ld(0,rp);
pp_vec = vec_ld(0,pp);
rp_vec = vec_add(rp_vec,pp_vec);
vec_st(rp_vec,0,rp);
pp += 16;
rp += 16;
istop -= 16;
}
if(istop % 16 > 0)
{
/* If byte count of row is not divisible by 16
* we will process remaining part as usual
*/
for (i = 0; i < istop; i++)
{
*rp = (png_byte)(((int)(*rp) + (int)(*pp++)) & 0xff);
rp++;
}
}
}
void png_read_filter_row_sub4_vsx(png_row_infop row_info, png_bytep row,
png_const_bytep prev_row)
{
const unsigned int bpp = 4;
png_size_t i;
png_size_t istop = row_info->rowbytes;
unsigned int bpp = (row_info->pixel_depth + 7) >> 3;
png_bytep rp = row + bpp;
PNG_UNUSED(prev_row)
for (i = bpp; i < istop; i++)
{
*rp = (png_byte)(((int)(*rp) + (int)(*(rp-bpp))) & 0xff);
*rp = (png_byte)(((int)(*rp) + (int)(*(rp-4))) & 0xff);
rp++;
}
}
@ -66,16 +91,16 @@ void png_read_filter_row_sub4_vsx(png_row_infop row_info, png_bytep row,
void png_read_filter_row_sub3_vsx(png_row_infop row_info, png_bytep row,
png_const_bytep prev_row)
{
const unsigned int bpp = 4;
png_size_t i;
png_size_t istop = row_info->rowbytes;
unsigned int bpp = (row_info->pixel_depth + 7) >> 3;
png_bytep rp = row + bpp;
PNG_UNUSED(prev_row)
for (i = bpp; i < istop; i++)
{
*rp = (png_byte)(((int)(*rp) + (int)(*(rp-bpp))) & 0xff);
*rp = (png_byte)(((int)(*rp) + (int)(*(rp-3))) & 0xff);
rp++;
}
}