[gimp] app: slight optimization of sse2 for src_atop

[Øyvind Kolås <ok src gnome org>]

commit 09af8dbca5316e2dfc979833e1d38ec830ec3c4f
Author: Øyvind Kolås <pippin gimp org>
Date:   Wed Jan 25 20:24:50 2017 +0100

    app: slight optimization of sse2 for src_atop

 .../layer-modes/gimpoperationlayermode.c           |    6 +++---
 1 files changed, 3 insertions(+), 3 deletions(-)
---
diff --git a/app/operations/layer-modes/gimpoperationlayermode.c 
b/app/operations/layer-modes/gimpoperationlayermode.c
index 6af2bb1..15d27f1 100644
--- a/app/operations/layer-modes/gimpoperationlayermode.c
+++ b/app/operations/layer-modes/gimpoperationlayermode.c
@@ -572,13 +572,12 @@ compfun_src_atop_sse2 (gfloat *in,
      
       while (samples--)
       {
-        __v4sf  alpha, rgba_in, rgba_layer, out_alpha;
+        __v4sf  alpha, rgba_in, rgba_layer;
 
         rgba_in    = *v_in ++;
         rgba_layer = *v_layer++;
 
         alpha = (__v4sf)_mm_shuffle_epi32((__m128i)rgba_layer,_MM_SHUFFLE(3,3,3,3)) * v_opacity;
-        out_alpha = (__v4sf)_mm_shuffle_epi32((__m128i)rgba_in,_MM_SHUFFLE(3,3,3,3));
 
         if (mask)
           {
@@ -587,8 +586,9 @@ compfun_src_atop_sse2 (gfloat *in,
 
         if (_mm_ucomigt_ss (alpha, _mm_setzero_ps ()))
           {
-            __v4sf out_pixel, out_pixel_rbaa;
+            __v4sf out_pixel, out_pixel_rbaa, out_alpha;
 
+            out_alpha      = (__v4sf)_mm_shuffle_epi32((__m128i)rgba_in,_MM_SHUFFLE(3,3,3,3));
             out_pixel      = rgba_layer * alpha + rgba_in * (v_one - alpha);
             out_pixel_rbaa = _mm_shuffle_ps (out_pixel, out_alpha, _MM_SHUFFLE (3, 3, 2, 0));
             out_pixel      = _mm_shuffle_ps (out_pixel, out_pixel_rbaa, _MM_SHUFFLE (2, 1, 1, 0));