vp9: add 16x16 idct avx2 (8-bit).

checkasm --bench, 10k runs, for *_add_${bpc}_${sub_idct}_${opt}, shows
that it's about 1.65x as fast as the AVX version for the full IDCT, and
similar speedups for the sub-IDCTs:

nop: 24.6
vp9_inv_dct_dct_16x16_add_8_1_c: 6444.8
vp9_inv_dct_dct_16x16_add_8_1_sse2: 638.6
vp9_inv_dct_dct_16x16_add_8_1_ssse3: 484.4
vp9_inv_dct_dct_16x16_add_8_1_avx: 661.2
vp9_inv_dct_dct_16x16_add_8_1_avx2: 311.5
vp9_inv_dct_dct_16x16_add_8_2_c: 6665.7
vp9_inv_dct_dct_16x16_add_8_2_sse2: 646.9
vp9_inv_dct_dct_16x16_add_8_2_ssse3: 455.2
vp9_inv_dct_dct_16x16_add_8_2_avx: 521.9
vp9_inv_dct_dct_16x16_add_8_2_avx2: 304.3
vp9_inv_dct_dct_16x16_add_8_4_c: 7022.7
vp9_inv_dct_dct_16x16_add_8_4_sse2: 647.4
vp9_inv_dct_dct_16x16_add_8_4_ssse3: 467.1
vp9_inv_dct_dct_16x16_add_8_4_avx: 446.1
vp9_inv_dct_dct_16x16_add_8_4_avx2: 297.0
vp9_inv_dct_dct_16x16_add_8_8_c: 6800.4
vp9_inv_dct_dct_16x16_add_8_8_sse2: 598.6
vp9_inv_dct_dct_16x16_add_8_8_ssse3: 465.7
vp9_inv_dct_dct_16x16_add_8_8_avx: 440.9
vp9_inv_dct_dct_16x16_add_8_8_avx2: 290.2
vp9_inv_dct_dct_16x16_add_8_16_c: 6626.6
vp9_inv_dct_dct_16x16_add_8_16_sse2: 599.5
vp9_inv_dct_dct_16x16_add_8_16_ssse3: 475.0
vp9_inv_dct_dct_16x16_add_8_16_avx: 469.9
vp9_inv_dct_dct_16x16_add_8_16_avx2: 286.4

1 files changed, 68 insertions, 1 deletions

diff --git a/libavutil/x86/x86util.asm b/libavutil/x86/x86util.asm
index e7493f4883..44ed750ae5 100644
--- a/libavutil/x86/x86util.asm
+++ b/libavutil/x86/x86util.asm
@@ -30,7 +30,10 @@
 %include "libavutil/x86/x86inc.asm"
 
 %macro SBUTTERFLY 4
-%if avx_enabled == 0
+%ifidn %1, dqqq
+    vperm2i128  m%4, m%2, m%3, q0301
+    vinserti128 m%2, m%2, xm%3, 1
+%elif avx_enabled == 0
     mova      m%4, m%2
     punpckl%1 m%2, m%3
     punpckh%1 m%4, m%3
@@ -193,6 +196,70 @@
 %endif
 %endmacro
 
+%macro TRANSPOSE16x16W 18-19
+; in:  m0..m15, unless %19 in which case m6 is in %17
+; out: m0..m15, unless %19 in which case m4 is in %18
+; spills into %17 and %18
+%if %0 < 19
+    mova       %17, m%7
+%endif
+
+    SBUTTERFLY dqqq, %1,  %9, %7
+    SBUTTERFLY dqqq, %2, %10, %7
+    SBUTTERFLY dqqq, %3, %11, %7
+    SBUTTERFLY dqqq, %4, %12, %7
+    SBUTTERFLY dqqq, %5, %13, %7
+    SBUTTERFLY dqqq, %6, %14, %7
+    mova       %18, m%14
+    mova       m%7, %17
+    SBUTTERFLY dqqq, %7, %15, %14
+    SBUTTERFLY dqqq, %8, %16, %14
+
+    SBUTTERFLY  wd,  %1,  %2, %14
+    SBUTTERFLY  wd,  %3,  %4, %14
+    SBUTTERFLY  wd,  %5,  %6, %14
+    SBUTTERFLY  wd,  %7,  %8, %14
+    SBUTTERFLY  wd,  %9, %10, %14
+    SBUTTERFLY  wd, %11, %12, %14
+    mova       %17, m%12
+    mova      m%14, %18
+    SBUTTERFLY  wd, %13, %14, %12
+    SBUTTERFLY  wd, %15, %16, %12
+
+    SBUTTERFLY  dq,  %1,  %3, %12
+    SBUTTERFLY  dq,  %2,  %4, %12
+    SBUTTERFLY  dq,  %5,  %7, %12
+    SBUTTERFLY  dq,  %6,  %8, %12
+    SBUTTERFLY  dq,  %9, %11, %12
+    mova       %18, m%11
+    mova      m%12, %17
+    SBUTTERFLY  dq, %10, %12, %11
+    SBUTTERFLY  dq, %13, %15, %11
+    SBUTTERFLY  dq, %14, %16, %11
+
+    SBUTTERFLY qdq,  %1,  %5, %11
+    SBUTTERFLY qdq,  %2,  %6, %11
+    SBUTTERFLY qdq,  %3,  %7, %11
+    SBUTTERFLY qdq,  %4,  %8, %11
+
+    SWAP        %2, %5
+    SWAP        %4, %7
+
+    SBUTTERFLY qdq,  %9, %13, %11
+    SBUTTERFLY qdq, %10, %14, %11
+    mova      m%11, %18
+    mova       %18, m%5
+    SBUTTERFLY qdq, %11, %15, %5
+    SBUTTERFLY qdq, %12, %16, %5
+
+%if %0 < 19
+    mova       m%5, %18
+%endif
+
+    SWAP       %10, %13
+    SWAP       %12, %15
+%endmacro
+
 ; PABSW macro assumes %1 != %2, while ABS1/2 macros work in-place
 %macro PABSW 2
 %if cpuflag(ssse3)