[x264-devel] [PATCH 2/2] ppc: Add sub8x8_dct_dc

[Alexandra Hájková]

From: Alexandra Hajkova <alexandra at khirnov.net>

---
 common/dct.c     |  1 +
 common/ppc/dct.c | 53 +++++++++++++++++++++++++++++++++++++++++++++++++++++
 common/ppc/dct.h |  2 ++
 3 files changed, 56 insertions(+)

diff --git a/common/dct.c b/common/dct.c
index d59c2db..4052e3e 100644
--- a/common/dct.c
+++ b/common/dct.c
@@ -726,6 +726,7 @@ void x264_dct_init( int cpu, x264_dct_function_t *dctf )
         dctf->add8x8_idct   = x264_add8x8_idct_altivec;
         dctf->add16x16_idct = x264_add16x16_idct_altivec;
 
+        dctf->sub8x8_dct_dc = x264_sub8x8_dct_dc_altivec;
         dctf->sub8x8_dct8   = x264_sub8x8_dct8_altivec;
         dctf->sub16x16_dct8 = x264_sub16x16_dct8_altivec;
 
diff --git a/common/ppc/dct.c b/common/ppc/dct.c
index 3c04c77..6fd0a10 100644
--- a/common/ppc/dct.c
+++ b/common/ppc/dct.c
@@ -113,6 +113,59 @@ void x264_sub16x16_dct_altivec( int16_t dct[16][16], uint8_t *pix1, uint8_t *pix
  * 8x8 transform:
  ***************************************************************************/
 
+static void pix_diff(uint8_t *p1, uint8_t *p2, vec_s16_t *diff, int i)
+{
+    vec_s16_t pix1v, pix2v, tmp[4];
+    vec_u8_t pix1v8, pix2v8;
+    LOAD_ZERO;
+
+    for (int j = 0; j < 4; j++) {
+        pix1v8 = vec_vsx_ld( 0, p1 );
+        pix2v8 = vec_vsx_ld( 0, p2 );
+        pix1v = vec_u8_to_s16_h( pix1v8 );
+        pix2v = vec_u8_to_s16_h( pix2v8 );
+        tmp[j] = vec_sub( pix1v, pix2v);
+        p1 += FENC_STRIDE;
+        p2 += FDEC_STRIDE;
+    }
+    diff[i] = vec_add(tmp[0], tmp[1]);
+    diff[i] = vec_add(diff[i], tmp[2]);
+    diff[i] = vec_add(diff[i], tmp[3]);
+}
+
+void x264_sub8x8_dct_dc_altivec( int16_t dct[4], uint8_t *pix1, uint8_t *pix2 )
+{
+    vec_s16_t diff[2];
+    vec_s32_t sum[2];
+    vec_s32_t zero32 = vec_splat_s32(0);
+    vec_u8_t mask = { 0x00, 0x01, 0x02, 0x03, 0x04, 0x05, 0x06, 0x07,
+                      0x18, 0x19, 0x1A, 0x1B, 0x1C, 0x1D, 0x1E, 0x1F };
+
+    pix_diff(&pix1[0], &pix2[0], diff, 0);
+    pix_diff(&pix1[4*FENC_STRIDE], &pix2[4*FDEC_STRIDE], diff, 1);
+
+    sum[0] = vec_sum4s(diff[0], zero32);
+    sum[1] = vec_sum4s(diff[1], zero32);
+    diff[0] = vec_packs(sum[0], sum[1]);
+    sum[0] = vec_sum4s(diff[0], zero32);
+    diff[0] = vec_packs(sum[0], zero32);
+
+    diff[1] = vec_vsx_ld(0, dct);
+    diff[0] = vec_perm( diff[0], diff[1], mask);
+
+    vec_vsx_st(diff[0], 0, dct);
+
+    /* 2x2 DC transform */
+    int d0 = dct[0] + dct[1];
+    int d1 = dct[2] + dct[3];
+    int d2 = dct[0] - dct[1];
+    int d3 = dct[2] - dct[3];
+    dct[0] = d0 + d1;
+    dct[1] = d0 - d1;
+    dct[2] = d2 + d3;
+    dct[3] = d2 - d3;
+}
+
 /* DCT8_1D unrolled by 8 in Altivec */
 #define DCT8_1D_ALTIVEC( dct0v, dct1v, dct2v, dct3v, dct4v, dct5v, dct6v, dct7v ) \
 { \
diff --git a/common/ppc/dct.h b/common/ppc/dct.h
index 4011b8f..4f17c7f 100644
--- a/common/ppc/dct.h
+++ b/common/ppc/dct.h
@@ -37,6 +37,8 @@ void x264_add4x4_idct_altivec( uint8_t *p_dst, int16_t dct[16] );
 void x264_add8x8_idct_altivec( uint8_t *p_dst, int16_t dct[4][16] );
 void x264_add16x16_idct_altivec( uint8_t *p_dst, int16_t dct[16][16] );
 
+
+void x264_sub8x8_dct_dc_altivec( int16_t dct[4], uint8_t *pix1, uint8_t *pix2 );
 void x264_sub8x8_dct8_altivec( int16_t dct[64], uint8_t *pix1, uint8_t *pix2 );
 void x264_sub16x16_dct8_altivec( int16_t dct[4][64], uint8_t *pix1, uint8_t *pix2 );
 
-- 
2.7.4