Add SSE optimizations to SincResampler.

media/base/sinc_resampler_unittest.cc

Index: media/base/sinc_resampler_unittest.cc
diff --git a/media/base/sinc_resampler_unittest.cc b/media/base/sinc_resampler_unittest.cc
index 9bf7ba4409b97d0ffbdbfbc267f900535df96073..58856eced885f462170cfb4814c8a72287369cf6 100644
--- a/media/base/sinc_resampler_unittest.cc
+++ b/media/base/sinc_resampler_unittest.cc
@@ -9,9 +9,9 @@
 
 #include "base/bind.h"
 #include "base/bind_helpers.h"
+#include "base/format_macros.h"
 #include "base/logging.h"
-#include "base/memory/scoped_ptr.h"
-#include "base/stringprintf.h"
+#include "base/time.h"
 #include "media/base/sinc_resampler.h"
 #include "testing/gmock/include/gmock/gmock.h"
 #include "testing/gtest/include/gtest/gtest.h"
@@ -20,6 +20,9 @@ using testing::_;
 
 namespace media {
 
+static const double kSampleRateRatio = 192000.0 / 44100.0;
+static const double kKernelInterpolationFactor = 0.5;
+
 // Helper class to ensure ChunkedResample() functions properly.
 class MockSource {
  public:
@@ -33,7 +36,6 @@ TEST(SincResamplerTest, ChunkedResample) {
 
   // Choose a high ratio of input to output samples which will result in quick
   // exhaustion of SincResampler's internal buffers.
-  static const double kSampleRateRatio = 192000.0 / 44100.0;
   SincResampler resampler(
       kSampleRateRatio,
       base::Bind(&MockSource::ProvideInput, base::Unretained(&mock_source)));
@@ -52,6 +54,88 @@ TEST(SincResamplerTest, ChunkedResample) {
   resampler.Resample(resampled_destination.get(), max_chunk_size);
 }
 
+// Ensure various optimized Convolve() methods return the same value.  Only run
+// this test if other optimized methods exist, otherwise the default Convolve()
+// will be tested by the parameterized SincResampler tests below.
+#if defined(ARCH_CPU_X86_FAMILY) && defined(__SSE__)
+TEST(SincResamplerTest, Convolve) {
+  // Initialize a dummy resampler.
+  MockSource mock_source;
+  SincResampler resampler(
+      kSampleRateRatio,
+      base::Bind(&MockSource::ProvideInput, base::Unretained(&mock_source)));
+
+  // Convolve_SSE() is slightly more precise than Conolve_C(), so comparison
+  // must be done using an epsilon.
+  static const double kEpsilon = 0.00000005;
+
+  // Use a kernel from SincResampler as input and kernel data, this has the
+  // benefit of already being properly sized and aligned for Convolve_SSE().
+  double result = resampler.Convolve_C(
+      resampler.kernel_storage_.get(), resampler.kernel_storage_.get(),
+      resampler.kernel_storage_.get(), kKernelInterpolationFactor);
+  double result2 = resampler.Convolve_SSE(
+      resampler.kernel_storage_.get(), resampler.kernel_storage_.get(),
+      resampler.kernel_storage_.get(), kKernelInterpolationFactor);
+  EXPECT_NEAR(result2, result, kEpsilon);
+
+  // Test Convolve_SSE() w/ unaligned input pointer.
+  result = resampler.Convolve_C(
+      resampler.kernel_storage_.get() + 1, resampler.kernel_storage_.get(),
+      resampler.kernel_storage_.get(), kKernelInterpolationFactor);
+  result2 = resampler.Convolve_SSE(
+      resampler.kernel_storage_.get() + 1, resampler.kernel_storage_.get(),
+      resampler.kernel_storage_.get(), kKernelInterpolationFactor);
+  EXPECT_NEAR(result2, result, kEpsilon);
+}
+#endif
+
+// Benchmark for the various Convolve() methods.

[Ami GONE FROM CHROMIUM, 2012/07/21 17:25:10]

Comment that this is only DISABLED_ for the benefit of bot cycle time?

Maybe a better move is to instead check it in with kConvolveIterations of 10 or
something, and let benchmarkers up that in their builds? (or make it runtime
settable, like with a flag or env var).

[DaleCurtis, 2012/07/24 00:13:07]

Done. --convolve-iterations is runtime settable.

+TEST(SincResamplerTest, DISABLED_ConvolveBenchmark) {
+  // Initialize a dummy resampler.
+  MockSource mock_source;
+  SincResampler resampler(
+      kSampleRateRatio,
+      base::Bind(&MockSource::ProvideInput, base::Unretained(&mock_source)));
+
+  static const int kConvolveIterations = 50000000;
+
+  // Benchmark Convolve_C().
+  base::TimeTicks start = base::TimeTicks::HighResNow();
+  for (int i = 0; i < kConvolveIterations; ++i) {
+    resampler.Convolve_C(
+        resampler.kernel_storage_.get(), resampler.kernel_storage_.get(),
+        resampler.kernel_storage_.get(), kKernelInterpolationFactor);
+  }
+  base::TimeTicks end = base::TimeTicks::HighResNow();
+  printf("Convolve_C took %" PRId64 "ms for %d iterations.\n",
+         (end - start).InMilliseconds(), kConvolveIterations);
+
+#if defined(ARCH_CPU_X86_FAMILY) && defined(__SSE__)
+  // Benchmark Convolve_SSE() with aligned input pointer.
+  start = base::TimeTicks::HighResNow();
+  for (int j = 0; j < kConvolveIterations; ++j) {
+    resampler.Convolve_SSE(
+        resampler.kernel_storage_.get(), resampler.kernel_storage_.get(),
+        resampler.kernel_storage_.get(), kKernelInterpolationFactor);
+  }
+  end = base::TimeTicks::HighResNow();
+  printf("Convolve_SSE (aligned) took %" PRId64 "ms for %d iterations.\n",
+         (end - start).InMilliseconds(), kConvolveIterations);
+
+  // Benchmark Convolve_SSE() with unaligned input pointer.
+  start = base::TimeTicks::HighResNow();
+  for (int j = 0; j < kConvolveIterations; ++j) {
+    resampler.Convolve_SSE(
+        resampler.kernel_storage_.get() + 1, resampler.kernel_storage_.get(),
+        resampler.kernel_storage_.get(), kKernelInterpolationFactor);
+  }
+  end = base::TimeTicks::HighResNow();
+  printf("Convolve_SSE (unaligned) took %" PRId64 "ms for %d iterations.\n",
+         (end - start).InMilliseconds(), kConvolveIterations);
+#endif

[Ami GONE FROM CHROMIUM, 2012/07/21 17:25:10]

Add an output for the relative improvement between C and SSE?

[DaleCurtis, 2012/07/24 00:13:07]

Done.

+}
+
 // Fake audio source for testing the resampler.  Generates a sinusoidal linear
 // chirp (http://en.wikipedia.org/wiki/Chirp) which can be tuned to stress the
 // resampler for the specific sample rate conversion being used.