x86: sbrdsp: Implement SSE sum64x5

698 to 174 cycles on Arrandale. Unrolling is a 6 cycles gain.
Signed-off-by: Diego Biurrun <diego@biurrun.de>

libavcodec/x86/sbrdsp.asm

@@ -181,3 +181,25 @@ cglobal sbr_hf_gen, 4,4,8, X_high, X_low, alpha0, alpha1, BW, S, E
     add     start, 16
     jnz         .loop2
     RET
+
+cglobal sbr_sum64x5, 1,2,4,z
+    lea    r1q, [zq+ 256]
+.loop:
+    mova    m0, [zq+   0]
+    mova    m2, [zq+  16]
+    mova    m1, [zq+ 256]
+    mova    m3, [zq+ 272]
+    addps   m0, [zq+ 512]
+    addps   m2, [zq+ 528]
+    addps   m1, [zq+ 768]
+    addps   m3, [zq+ 784]
+    addps   m0, [zq+1024]
+    addps   m2, [zq+1040]
+    addps   m0, m1
+    addps   m2, m3
+    mova  [zq], m0
+    mova  [zq+16], m2
+    add     zq, 32
+    cmp     zq, r1q
+    jne  .loop
+    REP_RET

libavcodec/x86/sbrdsp_init.c

@@ -25,6 +25,7 @@
 #include "libavcodec/sbrdsp.h"
 
 float ff_sbr_sum_square_sse(float (*x)[2], int n);
+void ff_sbr_sum64x5_sse(float *z);
 void ff_sbr_hf_g_filt_sse(float (*Y)[2], const float (*X_high)[40][2],
                           const float *g_filt, int m_max, intptr_t ixh);
 void ff_sbr_hf_gen_sse(float (*X_high)[2], const float (*X_low)[2],
@@ -37,6 +38,7 @@ void ff_sbrdsp_init_x86(SBRDSPContext *s)
 
     if (EXTERNAL_SSE(mm_flags)) {
         s->sum_square = ff_sbr_sum_square_sse;
+        s->sum64x5    = ff_sbr_sum64x5_sse;
         s->hf_g_filt  = ff_sbr_hf_g_filt_sse;
         s->hf_gen     = ff_sbr_hf_gen_sse;
     }