[x265] [PATCH Only Review] ASM routine for luma filter for 8x8 block

[nabajit at multicorewareinc.com]

# HG changeset patch
# User Nabajit Deka
# Date 1381153349 -19800
#      Mon Oct 07 19:12:29 2013 +0530
# Node ID 2f32b808deb2bb50064bde859adcc538f48a92f5
# Parent  c010342f7605c86867824f5b525a8f84c0d2de1c
ASM routine for luma filter for 8x8 block.

diff -r c010342f7605 -r 2f32b808deb2 source/common/x86/ipfilter8.asm
--- a/source/common/x86/ipfilter8.asm	Sun Oct 06 02:09:00 2013 -0500
+++ b/source/common/x86/ipfilter8.asm	Mon Oct 07 19:12:29 2013 +0530
@@ -130,3 +130,57 @@
     RET
 
 %endif  ; ARCH_X86_64 == 0
+
+
+SECTION_RODATA 32
+
+tab_Tm8:    db 0, 1, 2, 3, 4, 5, 6, 7, 1, 2, 3, 4, 5, 6, 7, 8
+            db 2, 3, 4, 5, 6, 7, 8, 9, 3, 4, 5, 6, 7, 8, 9, 10
+            db 4, 5, 6, 7, 8, 9, 10, 11, 5, 6, 7, 8, 9, 10, 11, 12
+            db 6, 7, 8, 9, 10, 11, 12, 13, 7, 8, 9, 10, 11, 12, 13, 14
+
+tab_c_512:  times 8 dw 512
+
+SECTION .text
+
+%macro FILTER_H8 3
+    movu        %1, [r0 - 3]
+    pshufb      %2, %1, [tab_Tm8]
+    pmaddubsw   %2, m3
+    pshufb      m7, %1, [tab_Tm8 + 16]
+    pmaddubsw   m7, m3
+    phaddw      %2, m7
+    pshufb      m7, %1, [tab_Tm8 + 32]
+    pmaddubsw   m7, m3
+    pshufb      %1, %1, [tab_Tm8 + 48]
+    pmaddubsw   %1, m3
+    phaddw      m7, %1
+    phaddw      %2, m7
+    pmulhrsw    %2, %3
+    packuswb    %2, %2
+%endmacro
+
+;-----------------------------------------------------------------------------
+; void filterHorizontal_p_p_8(pixel *src, intptr_t srcStride, pixel *dst, intptr_t dstStride, int width, int height, short const *coeff)
+;-----------------------------------------------------------------------------
+INIT_XMM sse4
+cglobal filterHorizontal_p_p_8, 4, 5, 5
+
+    mov       r4, r6m
+    movu      m3, [r4]
+    packsswb  m3, m3
+
+    mova      m2, [tab_c_512]
+
+%rep 7
+    FILTER_H8   m0, m1, m2
+    movh        [r2], m1
+          
+    add         r0, r1
+    add         r2, r3
+%endrep
+
+    FILTER_H8   m0, m1, m2
+    movh        [r2], m1
+
+    RET