Add sk_parallel_for()

tools/skpdiff/SkDiffContext.cpp

 /*
  * Copyright 2013 Google Inc.
  *
  * Use of this source code is governed by a BSD-style license that can be
  * found in the LICENSE file.
  */
 
 #include "SkBitmap.h"
 #include "SkImageDecoder.h"
 #include "SkOSFile.h"
@@ skipping 191 matching lines @@
                                                        newRecord->fCommonName.c_str());
             SkImageEncoder::EncodeFile(newRecord->fWhiteDiffPath.c_str(),
                                        diffData.fResult.whiteDiffBitmap,
                                        SkImageEncoder::kPNG_Type, 100);
             diffData.fResult.whiteDiffBitmap.reset();
             bitmapsToCreate.whiteDiff = false;
         }
     }
 }
 
-class SkThreadedDiff : public SkRunnable {
-public:
-    SkThreadedDiff() : fDiffContext(NULL) { }
-
-    void setup(SkDiffContext* diffContext, const SkString& baselinePath, const SkString& testPath) {
-        fDiffContext = diffContext;
-        fBaselinePath = baselinePath;
-        fTestPath = testPath;
-    }
-
-    void run() override {
-        fDiffContext->addDiff(fBaselinePath.c_str(), fTestPath.c_str());
-    }
-
-private:
-    SkDiffContext* fDiffContext;
-    SkString fBaselinePath;
-    SkString fTestPath;
-};
-
 void SkDiffContext::diffDirectories(const char baselinePath[], const char testPath[]) {
     // Get the files in the baseline, we will then look for those inside the test path
     SkTArray<SkString> baselineEntries;
     if (!get_directory(baselinePath, &baselineEntries)) {
         SkDebugf("Unable to open path \"%s\"\n", baselinePath);
         return;
     }
 
-    SkTaskGroup tg;
-    SkTArray<SkThreadedDiff> runnableDiffs;
-    runnableDiffs.reset(baselineEntries.count());
-
-    for (int x = 0; x < baselineEntries.count(); x++) {
-        const char* baseFilename = baselineEntries[x].c_str();
+    sk_parallel_for(baselineEntries.count(), [&](int i) {
+        const char* baseFilename = baselineEntries[i].c_str();
 
         // Find the real location of each file to compare
         SkString baselineFile = SkOSPath::Join(baselinePath, baseFilename);
         SkString testFile = SkOSPath::Join(testPath, baseFilename);
 
         // Check that the test file exists and is a file
         if (sk_exists(testFile.c_str()) && !sk_isdir(testFile.c_str())) {
-            // Queue up the comparison with the differ
-            runnableDiffs[x].setup(this, baselineFile, testFile);
-            tg.add(&runnableDiffs[x]);
+            this->addDiff(baselineFile.c_str(), testFile.c_str());
         } else {
             SkDebugf("Baseline file \"%s\" has no corresponding test file\n", baselineFile.c_str());
         }
-    }
+    });
 }
 
 
 void SkDiffContext::diffPatterns(const char baselinePattern[], const char testPattern[]) {
     // Get the files in the baseline and test patterns. Because they are in sorted order, it's easy
     // to find corresponding images by matching entry indices.
 
     SkTArray<SkString> baselineEntries;
     if (!glob_files(baselinePattern, &baselineEntries)) {
         SkDebugf("Unable to get pattern \"%s\"\n", baselinePattern);
         return;
     }
 
     SkTArray<SkString> testEntries;
     if (!glob_files(testPattern, &testEntries)) {
         SkDebugf("Unable to get pattern \"%s\"\n", testPattern);
         return;
     }
 
     if (baselineEntries.count() != testEntries.count()) {
         SkDebugf("Baseline and test patterns do not yield corresponding number of files\n");
         return;
     }
 
-    SkTaskGroup tg;
-    SkTArray<SkThreadedDiff> runnableDiffs;
-    runnableDiffs.reset(baselineEntries.count());
-
-    for (int x = 0; x < baselineEntries.count(); x++) {
-        runnableDiffs[x].setup(this, baselineEntries[x], testEntries[x]);
-        tg.add(&runnableDiffs[x]);
-    }
-    tg.wait();
+    sk_parallel_for(baselineEntries.count(), [&](int i) {
+        this->addDiff(baselineEntries[i].c_str(), testEntries[i].c_str());
+    });
 }
 
 void SkDiffContext::outputRecords(SkWStream& stream, bool useJSONP) {
     SkTLList<DiffRecord>::Iter iter(fRecords, SkTLList<DiffRecord>::Iter::kHead_IterStart);
     DiffRecord* currentRecord = iter.get();
 
     if (useJSONP) {
         stream.writeText("var SkPDiffRecords = {\n");
     } else {
         stream.writeText("{\n");
@@ skipping 149 matching lines @@
         for (int i = 0; i < cntColumns; i++) {
             SkString str;
             str.printf(", %f", values[i]);
             stream.writeText(str.c_str());
         }
         stream.writeText("\n");
 
         currentRecord = iter2.next();
     }
 }