Stop creating CodecSrcs with unused scale

dm/DM.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 "CrashHandler.h"
 #include "DMJsonWriter.h"
 #include "DMSrcSink.h"
@@ skipping 463 matching lines @@
     if (!encoded) {
         info("Couldn't read %s.", path.c_str());
         return;
     }
     SkAutoTDelete<SkCodec> codec(SkCodec::NewFromData(encoded));
     if (nullptr == codec.get()) {
         info("Couldn't create codec for %s.", path.c_str());
         return;
     }
 
-    // Native Scales
-    // SkJpegCodec natively supports scaling to: 0.125, 0.25, 0.375, 0.5, 0.625, 0.75, 0.875
-    const float nativeScales[] = { 0.125f, 0.25f, 0.375f, 0.5f, 0.625f, 0.750f, 0.875f, 1.0f };
+    // native scaling is only supported by WEBP and JPEG
+    bool supportsNativeScaling = false;
 
     SkTArray<CodecSrc::Mode> nativeModes;
     nativeModes.push_back(CodecSrc::kCodec_Mode);
     nativeModes.push_back(CodecSrc::kCodecZeroInit_Mode);
     switch (codec->getEncodedFormat()) {
         case SkEncodedFormat::kJPEG_SkEncodedFormat:
             nativeModes.push_back(CodecSrc::kScanline_Mode);
             nativeModes.push_back(CodecSrc::kStripe_Mode);
             nativeModes.push_back(CodecSrc::kCroppedScanline_Mode);
+            supportsNativeScaling = true;
             break;
         case SkEncodedFormat::kWEBP_SkEncodedFormat:
             nativeModes.push_back(CodecSrc::kSubset_Mode);
+            supportsNativeScaling = true;
             break;
         case SkEncodedFormat::kDNG_SkEncodedFormat:
             break;
         default:
             nativeModes.push_back(CodecSrc::kScanline_Mode);
             break;
     }
 
     SkTArray<CodecSrc::DstColorType> colorTypes;
     colorTypes.push_back(CodecSrc::kGetFromCanvas_DstColorType);
@@ skipping 13 matching lines @@
     }
 
     SkTArray<SkAlphaType> alphaModes;
     alphaModes.push_back(kPremul_SkAlphaType);
     alphaModes.push_back(kUnpremul_SkAlphaType);
     if (codec->getInfo().alphaType() == kOpaque_SkAlphaType) {
         alphaModes.push_back(kOpaque_SkAlphaType);
     }
 
     for (CodecSrc::Mode mode : nativeModes) {
-        for (float scale : nativeScales) {
-            for (CodecSrc::DstColorType colorType : colorTypes) {
-                for (SkAlphaType alphaType : alphaModes) {
-                    // Only test kCroppedScanline_Mode when the alpha type is opaque.  The test is
-                    // slow and won't be interestingly different with different alpha types.
-                    if (CodecSrc::kCroppedScanline_Mode == mode &&
-                            kOpaque_SkAlphaType != alphaType) {
-                        continue;
+        for (CodecSrc::DstColorType colorType : colorTypes) {
+            for (SkAlphaType alphaType : alphaModes) {
+                // Only test kCroppedScanline_Mode when the alpha type is opaque.  The test is
+                // slow and won't be interestingly different with different alpha types.
+                if (CodecSrc::kCroppedScanline_Mode == mode &&
+                        kOpaque_SkAlphaType != alphaType) {
+                    continue;
+                }
+
+                push_codec_src(path, mode, colorType, alphaType, 1.0f);
+
+                // Skip kNonNative on different native scales.  It won't be interestingly
+                // different.
+                if (supportsNativeScaling &&
+                        CodecSrc::kNonNative8888_Always_DstColorType == colorType) {
+                    // Native Scales
+                    // SkJpegCodec natively supports scaling to the following:
+                    for (auto scale : { 0.125f, 0.25f, 0.375f, 0.5f, 0.625f, 0.750f, 0.875f }) {
+                        push_codec_src(path, mode, colorType, alphaType, scale);
                     }
-
-                    // Skip kNonNative on different native scales.  It won't be interestingly
-                    // different.
-                    if (CodecSrc::kNonNative8888_Always_DstColorType == colorType && 1.0f != scale)
-                    {
-                        continue;
-                    }
-
-                    push_codec_src(path, mode, colorType, alphaType, scale);
                 }
             }
         }
     }
 
     if (FLAGS_simpleCodec) {
         return;
     }
 
     const int sampleSizes[] = { 1, 2, 3, 4, 5, 6, 7, 8 };
@@ skipping 817 matching lines @@
 #endif
 }
 } // namespace skiatest
 
 #if !defined(SK_BUILD_FOR_IOS)
 int main(int argc, char** argv) {
     SkCommandLineFlags::Parse(argc, argv);
     return dm_main();
 }
 #endif