Use sse4.2 CRC32 instructions to hash when available.

bench/ChecksumBench.cpp

 /*
  * Copyright 2012 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 "SkCanvas.h"
 #include "SkChecksum.h"
+#include "SkOpts.h"
 #include "SkMD5.h"
 #include "SkRandom.h"
 #include "SkTemplates.h"
 
 enum ChecksumType {
     kMD5_ChecksumType,
-    kMurmur3_ChecksumType,
+    kHash_ChecksumType,
 };
 
 class ComputeChecksumBench : public Benchmark {
     enum {
         U32COUNT  = 256,
         SIZE      = U32COUNT * 4,
     };
     uint32_t    fData[U32COUNT];
     ChecksumType fType;
 
 public:
     ComputeChecksumBench(ChecksumType type) : fType(type) {
         SkRandom rand;
         for (int i = 0; i < U32COUNT; ++i) {
             fData[i] = rand.nextU();
         }
     }
 
     bool isSuitableFor(Backend backend) override {
         return backend == kNonRendering_Backend;
     }
 
 protected:
     const char* onGetName() override {
         switch (fType) {
             case kMD5_ChecksumType: return "compute_md5";
-            case kMurmur3_ChecksumType: return "compute_murmur3";
+            case kHash_ChecksumType: return "compute_hash";
 
             default: SK_ABORT("Invalid Type"); return "";
         }
     }
 
     void onDraw(int loops, SkCanvas*) override {
         switch (fType) {
             case kMD5_ChecksumType: {
                 for (int i = 0; i < loops; i++) {
                     SkMD5 md5;
                     md5.write(fData, sizeof(fData));
                     SkMD5::Digest digest;
                     md5.finish(digest);
                 }
             } break;
-            case kMurmur3_ChecksumType: {
+            case kHash_ChecksumType: {
                 for (int i = 0; i < loops; i++) {
-                    volatile uint32_t result = SkChecksum::Murmur3(fData, sizeof(fData));
+                    volatile uint32_t result = SkOpts::hash(fData, sizeof(fData));
                     sk_ignore_unused_variable(result);
                 }
             }break;
         }
 
     }
 
 private:
     typedef Benchmark INHERITED;
 };
 
 ///////////////////////////////////////////////////////////////////////////////
 
 DEF_BENCH( return new ComputeChecksumBench(kMD5_ChecksumType); )
-DEF_BENCH( return new ComputeChecksumBench(kMurmur3_ChecksumType); )
+DEF_BENCH( return new ComputeChecksumBench(kHash_ChecksumType); )