Add ARM NEON intrinsic optimizations for SincResampler.

media/base/sinc_resampler_unittest.cc

 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 // MSVC++ requires this to be set before any other includes to get M_PI.
 #define _USE_MATH_DEFINES
 
 #include <cmath>
 
 #include "base/bind.h"
@@ skipping 77 matching lines @@
   EXPECT_CALL(mock_source, ProvideInput(_, _))
       .Times(1).WillOnce(ClearBuffer());
   resampler.Resample(resampled_destination.get(), resampler.ChunkSize() / 2);
   for (int i = 0; i < resampler.ChunkSize() / 2; ++i)
     ASSERT_EQ(resampled_destination[i], 0);
 }
 
 // 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 Convolve_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(
+
+  double result2 = result;

[Ami GONE FROM CHROMIUM, 2012/09/21 04:41:41]

I don't like this b/c it'll make the test claim to pass (but be a no-op) on
other archs, and will silently regress if defines get changed, etc.

I think it's much safer to 
#else
#error Don't build this on this platform!
at l.123 (etc) and indeed only build this test on appropriate targets.

[DaleCurtis, 2012/09/24 19:54:37]

Done.

+#if defined(ARCH_CPU_X86_FAMILY) && defined(__SSE__)
+  result2 = resampler.Convolve_SSE(
       resampler.kernel_storage_.get(), resampler.kernel_storage_.get(),
       resampler.kernel_storage_.get(), kKernelInterpolationFactor);
+#elif defined(ARCH_CPU_ARM_FAMILY) && defined(__ARM_NEON__) && defined(USE_NEON)

[Ami GONE FROM CHROMIUM, 2012/09/21 04:41:41]

Here and elsewhere, I think __ARM_NEON__ is unnecessary given how USE_NEON comes
into being.

[DaleCurtis, 2012/09/24 19:54:37]

Done.

+  result2 = resampler.Convolve_NEON(
+      resampler.kernel_storage_.get(), resampler.kernel_storage_.get(),
+      resampler.kernel_storage_.get(), kKernelInterpolationFactor);
+#endif
   EXPECT_NEAR(result2, result, kEpsilon);
 
-  // Test Convolve_SSE() w/ unaligned input pointer.
+  // Test Convolve() w/ unaligned input pointer.
   result = resampler.Convolve_C(
       resampler.kernel_storage_.get() + 1, resampler.kernel_storage_.get(),
       resampler.kernel_storage_.get(), kKernelInterpolationFactor);
+#if defined(ARCH_CPU_X86_FAMILY) && defined(__SSE__)
   result2 = resampler.Convolve_SSE(
       resampler.kernel_storage_.get() + 1, resampler.kernel_storage_.get(),
       resampler.kernel_storage_.get(), kKernelInterpolationFactor);
+#elif defined(ARCH_CPU_ARM_FAMILY) && defined(__ARM_NEON__) && defined(USE_NEON)
+  result2 = resampler.Convolve_NEON(
+      resampler.kernel_storage_.get() + 1, resampler.kernel_storage_.get(),
+      resampler.kernel_storage_.get(), kKernelInterpolationFactor);
+#endif
   EXPECT_NEAR(result2, result, kEpsilon);
 }
-#endif
 
 // Benchmark for the various Convolve() methods.  Make sure to build with
 // branding=Chrome so that DCHECKs are compiled out when benchmarking.  Original
 // benchmarks were run with --convolve-iterations=50000000.
 TEST(SincResamplerTest, ConvolveBenchmark) {
   // Initialize a dummy resampler.
   MockSource mock_source;
   SincResampler resampler(
       kSampleRateRatio,
       base::Bind(&MockSource::ProvideInput, base::Unretained(&mock_source)));
 
   // Retrieve benchmark iterations from command line.
-  int convolve_iterations = 10;
+  int convolve_iterations = 50000000;

[Ami GONE FROM CHROMIUM, 2012/09/21 04:41:41]

what now?

[DaleCurtis, 2012/09/24 19:54:37]

Was just for benchmarking on the try bot, but sadly the trybots don't run the
unit tests :(

   std::string iterations(CommandLine::ForCurrentProcess()->GetSwitchValueASCII(
       kConvolveIterations));
   if (!iterations.empty())
     base::StringToInt(iterations, &convolve_iterations);
 
   printf("Benchmarking %d iterations:\n", convolve_iterations);
 
   // Benchmark Convolve_C().
   base::TimeTicks start = base::TimeTicks::HighResNow();
   for (int i = 0; i < convolve_iterations; ++i) {
@@ skipping 25 matching lines @@
     resampler.Convolve_SSE(
         resampler.kernel_storage_.get(), resampler.kernel_storage_.get(),
         resampler.kernel_storage_.get(), kKernelInterpolationFactor);
   }
   double total_time_sse_aligned_ms =
       (base::TimeTicks::HighResNow() - start).InMillisecondsF();
   printf("Convolve_SSE (aligned) took %.2fms; which is %.2fx faster than"
          " Convolve_C and %.2fx faster than Convolve_SSE (unaligned).\n",
          total_time_sse_aligned_ms, total_time_c_ms / total_time_sse_aligned_ms,
          total_time_sse_unaligned_ms / total_time_sse_aligned_ms);
+#elif defined(ARCH_CPU_ARM_FAMILY) && defined(__ARM_NEON__) && defined(USE_NEON)

[Ami GONE FROM CHROMIUM, 2012/09/21 04:41:41]

Like with the original SSE CL, IWBN to include benchmark results in the CL
description.

[DaleCurtis, 2012/09/24 19:54:37]

Done.

+  // Benchmark Convolve_NEON() with unaligned input pointer.
+  start = base::TimeTicks::HighResNow();
+  for (int j = 0; j < convolve_iterations; ++j) {
+    resampler.Convolve_NEON(
+        resampler.kernel_storage_.get() + 1, resampler.kernel_storage_.get(),
+        resampler.kernel_storage_.get(), kKernelInterpolationFactor);
+  }
+  double total_time_sse_unaligned_ms =

[Ami GONE FROM CHROMIUM, 2012/09/22 02:38:27]

there are a bunch of variables here and below that include "sse" in the name,
probably erroneously.

You could fix that with s/sse/neon/g, but probably better to instead dedup the
analysis code against the version above (and just keep the actual dispatch in
#if's).  For that matter, you could #define your way to a single codepath
entirely:
#if ...SSE...
#define CONVOLVE_OPT Convolve_SSE
#elif ...NEON...
#define CONVOLVE_OPT Convolve_NEON
#else
#error Boom!
#endif
...

[DaleCurtis, 2012/09/24 19:54:37]

Done.

+      (base::TimeTicks::HighResNow() - start).InMillisecondsF();
+  printf("Convolve_NEON (unaligned) took %.2fms; which is %.2fx faster than"
+         " Convolve_C.\n", total_time_sse_unaligned_ms,
+         total_time_c_ms / total_time_sse_unaligned_ms);
+
+  // Benchmark Convolve_NEON() with aligned input pointer.
+  start = base::TimeTicks::HighResNow();
+  for (int j = 0; j < convolve_iterations; ++j) {
+    resampler.Convolve_NEON(
+        resampler.kernel_storage_.get(), resampler.kernel_storage_.get(),
+        resampler.kernel_storage_.get(), kKernelInterpolationFactor);
+  }
+  double total_time_sse_aligned_ms =
+      (base::TimeTicks::HighResNow() - start).InMillisecondsF();
+  printf("Convolve_NEON (aligned) took %.2fms; which is %.2fx faster than"
+         " Convolve_C and %.2fx faster than Convolve_SSE (unaligned).\n",

[Ami GONE FROM CHROMIUM, 2012/09/22 02:38:27]

s/SSE/NEON/, I think :)

[DaleCurtis, 2012/09/24 19:54:37]

Done.

+         total_time_sse_aligned_ms, total_time_c_ms / total_time_sse_aligned_ms,
+         total_time_sse_unaligned_ms / total_time_sse_aligned_ms);
 #endif
 }
 
 // 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.
 class SinusoidalLinearChirpSource {
  public:
   SinusoidalLinearChirpSource(int sample_rate, int samples,
                               double max_frequency)
@@ skipping 182 matching lines @@
         std::tr1::make_tuple(11025, 192000, kResamplingRMSError, -62.61),
         std::tr1::make_tuple(16000, 192000, kResamplingRMSError, -63.14),
         std::tr1::make_tuple(22050, 192000, kResamplingRMSError, -62.42),
         std::tr1::make_tuple(32000, 192000, kResamplingRMSError, -63.38),
         std::tr1::make_tuple(44100, 192000, kResamplingRMSError, -62.63),
         std::tr1::make_tuple(48000, 192000, kResamplingRMSError, -73.44),
         std::tr1::make_tuple(96000, 192000, kResamplingRMSError, -73.52),
         std::tr1::make_tuple(192000, 192000, kResamplingRMSError, -73.52)));
 
 }  // namespace media