Sk4f: add floor()

bench/Sk4fBench.cpp

 /*
  * Copyright 2015 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "Benchmark.h"
 #include "SkColor.h"
 #include "SkNx.h"
@@ skipping 22 matching lines @@
         while (loops --> 0) {
             fs = SkNx_cast<float>(SkNx_cast<T>(fs));
         }
         fs.store((float*)blackhole);
     }
 };
 DEF_BENCH(return new Sk4fRoundtripBench<uint8_t>;)
 DEF_BENCH(return new Sk4fRoundtripBench<uint16_t>;)
 DEF_BENCH(return new Sk4fRoundtripBench<int>;)
 
+struct Sk4fFloorBench : public Benchmark {
+    Sk4fFloorBench() {}
+
+    const char* onGetName() override { return "Sk4f_floor"; }
+    bool isSuitableFor(Backend backend) override { return backend == kNonRendering_Backend; }
+
+    void onDraw(int loops, SkCanvas* canvas) override {
+        Sk4f fs(1,2,3,4);
+        while (loops --> 0) {
+            fs = fs.floor();
+        }
+        fs.store((float*)blackhole);
+    }
+};
+DEF_BENCH(return new Sk4fFloorBench;)
+
 struct Sk4fGradientBench : public Benchmark {
     const char* onGetName() override { return "Sk4f_gradient"; }
     bool isSuitableFor(Backend backend) override { return backend == kNonRendering_Backend; }
 
     SkPMColor fDevice[100];
     void onDraw(int loops, SkCanvas*) override {
         Sk4f c0(0,0,255,255),
              c1(255,0,0,255),
              dc = c1 - c0,
              fx(0.1f),
@@ skipping 10 matching lines @@
                 Sk4f_ToBytes((uint8_t*)(fDevice+i), a, b, c, d);
                 a = a + dcdx4;
                 b = b + dcdx4;
                 c = c + dcdx4;
                 d = d + dcdx4;
             }
         }
     }
 };
 DEF_BENCH(return new Sk4fGradientBench;)