vp9/x86: 16px MC functions (64bit only).

Cycle counts for large MCs (old -> new on ped1080p.webm, mx!=0&&my!=0):
16x8:    876 ->   870  (0.7%)
16x16:  1444 ->  1435  (0.7%)
16x32:  2784 ->  2748  (1.3%)
32x16:  2455 ->  2349  (4.5%)
32x32:  4641 ->  4084 (13.6%)
32x64:  9200 ->  7834 (17.4%)
64x32:  8980 ->  7197 (24.8%)
64x64: 17330 -> 13796 (25.6%)
Total decoding time goes from 9.326sec to 9.182sec.

libavcodec/x86/vp9dsp_init.c

@@ -56,6 +56,9 @@ mc_func(avg, sz, v, ssse3)
 
 mc_funcs(4);
 mc_funcs(8);
+#if ARCH_X86_64
+mc_funcs(16);
+#endif
 
 #undef mc_funcs
 #undef mc_func
@@ -78,7 +81,9 @@ mc_rep_func(avg, sz, hsz, h, ssse3); \
 mc_rep_func(put, sz, hsz, v, ssse3); \
 mc_rep_func(avg, sz, hsz, v, ssse3)
 
+#if ARCH_X86_32
 mc_rep_funcs(16, 8);
+#endif
 mc_rep_funcs(32, 16);
 mc_rep_funcs(64, 32);
 

libavcodec/x86/vp9mc.asm

@@ -145,6 +145,62 @@ INIT_XMM ssse3
 filter_h_fn put
 filter_h_fn avg
 
+%if ARCH_X86_64
+%macro filter_hx2_fn 1
+%assign %%px mmsize
+cglobal %1_8tap_1d_h_ %+ %%px, 6, 6, 14, dst, dstride, src, sstride, h, filtery
+    mova       m13, [pw_256]
+    mova        m8, [filteryq+ 0]
+    mova        m9, [filteryq+16]
+    mova       m10, [filteryq+32]
+    mova       m11, [filteryq+48]
+.loop:
+    movu        m0, [srcq-3]
+    movu        m1, [srcq-2]
+    movu        m2, [srcq-1]
+    movu        m3, [srcq+0]
+    movu        m4, [srcq+1]
+    movu        m5, [srcq+2]
+    movu        m6, [srcq+3]
+    movu        m7, [srcq+4]
+    add       srcq, sstrideq
+    SBUTTERFLY  bw, 0, 1, 12
+    SBUTTERFLY  bw, 2, 3, 12
+    SBUTTERFLY  bw, 4, 5, 12
+    SBUTTERFLY  bw, 6, 7, 12
+    pmaddubsw   m0, m8
+    pmaddubsw   m1, m8
+    pmaddubsw   m2, m9
+    pmaddubsw   m3, m9
+    pmaddubsw   m4, m10
+    pmaddubsw   m5, m10
+    pmaddubsw   m6, m11
+    pmaddubsw   m7, m11
+    paddw       m0, m2
+    paddw       m1, m3
+    paddw       m4, m6
+    paddw       m5, m7
+    paddsw      m0, m4
+    paddsw      m1, m5
+    pmulhrsw    m0, m13
+    pmulhrsw    m1, m13
+    packuswb    m0, m1
+%ifidn %1, avg
+    pavgb       m0, [dstq]
+%endif
+    mova    [dstq], m0
+    add       dstq, dstrideq
+    dec         hd
+    jg .loop
+    RET
+%endmacro
+
+INIT_XMM ssse3
+filter_hx2_fn put
+filter_hx2_fn avg
+
+%endif ; ARCH_X86_64
+
 %macro filter_v_fn 1
 %assign %%px mmsize/2
 %if ARCH_X86_64
@@ -220,6 +276,72 @@ INIT_XMM ssse3
 filter_v_fn put
 filter_v_fn avg
 
+%if ARCH_X86_64
+
+%macro filter_vx2_fn 1
+%assign %%px mmsize
+cglobal %1_8tap_1d_v_ %+ %%px, 6, 8, 14, dst, dstride, src, sstride, h, filtery, src4, sstride3
+    sub       srcq, sstrideq
+    lea  sstride3q, [sstrideq*3]
+    sub       srcq, sstrideq
+    mova       m13, [pw_256]
+    sub       srcq, sstrideq
+    mova        m8, [filteryq+ 0]
+    lea      src4q, [srcq+sstrideq*4]
+    mova        m9, [filteryq+16]
+    mova       m10, [filteryq+32]
+    mova       m11, [filteryq+48]
+.loop:
+    ; FIXME maybe reuse loads from previous rows, or just
+    ; more generally unroll this to prevent multiple loads of
+    ; the same data?
+    movu        m0, [srcq]
+    movu        m1, [srcq+sstrideq]
+    movu        m2, [srcq+sstrideq*2]
+    movu        m3, [srcq+sstride3q]
+    movu        m4, [src4q]
+    movu        m5, [src4q+sstrideq]
+    movu        m6, [src4q+sstrideq*2]
+    movu        m7, [src4q+sstride3q]
+    add       srcq, sstrideq
+    add      src4q, sstrideq
+    SBUTTERFLY  bw, 0, 1, 12
+    SBUTTERFLY  bw, 2, 3, 12
+    SBUTTERFLY  bw, 4, 5, 12
+    SBUTTERFLY  bw, 6, 7, 12
+    pmaddubsw   m0, m8
+    pmaddubsw   m1, m8
+    pmaddubsw   m2, m9
+    pmaddubsw   m3, m9
+    pmaddubsw   m4, m10
+    pmaddubsw   m5, m10
+    pmaddubsw   m6, m11
+    pmaddubsw   m7, m11
+    paddw       m0, m2
+    paddw       m1, m3
+    paddw       m4, m6
+    paddw       m5, m7
+    paddsw      m0, m4
+    paddsw      m1, m5
+    pmulhrsw    m0, m13
+    pmulhrsw    m1, m13
+    packuswb    m0, m1
+%ifidn %1, avg
+    pavgb       m0, [dstq]
+%endif
+    mova    [dstq], m0
+    add       dstq, dstrideq
+    dec         hd
+    jg .loop
+    RET
+%endmacro
+
+INIT_XMM ssse3
+filter_vx2_fn put
+filter_vx2_fn avg
+
+%endif ; ARCH_X86_64
+
 %macro fpel_fn 6
 %if %2 == 4
 %define %%srcfn movh