Add MSA optimized ARGB scaling functions

source/scale_argb.cc

Index: source/scale_argb.cc
diff --git a/source/scale_argb.cc b/source/scale_argb.cc
index 09c6e0ae1fc47461341fd8e304d6083c5a787ae6..17e61ba708b4f58fb152541d1e5447caaa735bc9 100644
--- a/source/scale_argb.cc
+++ b/source/scale_argb.cc
@@ -92,6 +92,22 @@ static void ScaleARGBDown2(int src_width,
     }
   }
 #endif
+#if defined(HAS_SCALEARGBROWDOWN2_MSA)
+  if (TestCpuFlag(kCpuHasMSA)) {
+    ScaleARGBRowDown2 =
+        filtering == kFilterNone
+            ? ScaleARGBRowDown2_Any_MSA
+            : (filtering == kFilterLinear ? ScaleARGBRowDown2Linear_Any_MSA
+                                          : ScaleARGBRowDown2Box_Any_MSA);
+    if (IS_ALIGNED(dst_width, 4)) {
+      ScaleARGBRowDown2 =
+          filtering == kFilterNone
+              ? ScaleARGBRowDown2_MSA
+              : (filtering == kFilterLinear ? ScaleARGBRowDown2Linear_MSA
+                                            : ScaleARGBRowDown2Box_MSA);
+    }
+  }
+#endif
 
   if (filtering == kFilterLinear) {
     src_stride = 0;
@@ -203,6 +219,16 @@ static void ScaleARGBDownEven(int src_width,
     }
   }
 #endif
+#if defined(HAS_SCALEARGBROWDOWNEVEN_MSA)
+  if (TestCpuFlag(kCpuHasMSA)) {
+    ScaleARGBRowDownEven = filtering ? ScaleARGBRowDownEvenBox_Any_MSA
+                                     : ScaleARGBRowDownEven_Any_MSA;
+    if (IS_ALIGNED(dst_width, 4)) {
+      ScaleARGBRowDownEven =
+          filtering ? ScaleARGBRowDownEvenBox_MSA : ScaleARGBRowDownEven_MSA;
+    }
+  }
+#endif
 
   if (filtering == kFilterLinear) {
     src_stride = 0;