Only use the gainmap shader if we might need it

Skip using the gainmap shader when drawing to a bitmap
with a known SDR colorspace as it'll be a no-op in
rendering results since W=1.0, but it'll be very expensive
in runtime due to CPU evaluation of the SKSL shader.

Before:
createScaledBitmapWithGainmap_median (ns): 179,455,037

After:
createScaledBitmapWithGainmap_median (ns): 15,643,742

Bug: 311085927
Test: benchmark in CL
Change-Id: I3f2506a2bd86bbe29c6e0837d31e4a231a7c182a

2 files changed, 43 insertions, 0 deletions

diff --git a/apct-tests/perftests/core/res/drawable-nodpi/fountain_night.jpg b/apct-tests/perftests/core/res/drawable-nodpi/fountain_night.jpg
new file mode 100644
index 000000000000..d8b2d759e4c0
--- /dev/null
+++ b/apct-tests/perftests/core/res/drawable-nodpi/fountain_night.jpg
diff --git a/apct-tests/perftests/core/src/android/graphics/perftests/CanvasPerfTest.java b/apct-tests/perftests/core/src/android/graphics/perftests/CanvasPerfTest.java
index f84a0d037ca5..e5a06c9bd146 100644
--- a/apct-tests/perftests/core/src/android/graphics/perftests/CanvasPerfTest.java
+++ b/apct-tests/perftests/core/src/android/graphics/perftests/CanvasPerfTest.java
@@ -16,20 +16,29 @@
 
 package android.graphics.perftests;
 
+import static org.junit.Assert.assertTrue;
+
+import android.content.Context;
 import android.graphics.Bitmap;
 import android.graphics.Bitmap.Config;
 import android.graphics.Color;
+import android.graphics.ImageDecoder;
 import android.graphics.Paint;
 import android.graphics.RecordingCanvas;
 import android.graphics.RenderNode;
 import android.perftests.utils.BenchmarkState;
 import android.perftests.utils.PerfStatusReporter;
 
+import androidx.test.InstrumentationRegistry;
 import androidx.test.filters.LargeTest;
 
+import com.android.perftests.core.R;
+
 import org.junit.Rule;
 import org.junit.Test;
 
+import java.io.IOException;
+
 @LargeTest
 public class CanvasPerfTest {
     @Rule
@@ -93,4 +102,38 @@ public class CanvasPerfTest {
             node.end(canvas);
         }
     }
+
+    @Test
+    public void testCreateScaledBitmap() throws IOException {
+        BenchmarkState state = mPerfStatusReporter.getBenchmarkState();
+        final Context context = InstrumentationRegistry.getContext();
+        Bitmap source = ImageDecoder.decodeBitmap(
+                ImageDecoder.createSource(context.getResources(), R.drawable.fountain_night),
+                (decoder, info, source1) -> {
+                    decoder.setAllocator(ImageDecoder.ALLOCATOR_SOFTWARE);
+                });
+        source.setGainmap(null);
+
+        while (state.keepRunning()) {
+            Bitmap.createScaledBitmap(source, source.getWidth() / 2, source.getHeight() / 2, true)
+                    .recycle();
+        }
+    }
+
+    @Test
+    public void testCreateScaledBitmapWithGainmap() throws IOException {
+        BenchmarkState state = mPerfStatusReporter.getBenchmarkState();
+        final Context context = InstrumentationRegistry.getContext();
+        Bitmap source = ImageDecoder.decodeBitmap(
+                ImageDecoder.createSource(context.getResources(), R.drawable.fountain_night),
+                (decoder, info, source1) -> {
+                    decoder.setAllocator(ImageDecoder.ALLOCATOR_SOFTWARE);
+                });
+        assertTrue(source.hasGainmap());
+
+        while (state.keepRunning()) {
+            Bitmap.createScaledBitmap(source, source.getWidth() / 2, source.getHeight() / 2, true)
+                    .recycle();
+        }
+    }
 }