WebRtcHybridAgc experiment: wire up AGC2 SIMD kill switches

AGC2 includes SIMD optimizations for different platforms.
Recently, SSE2 and NEON code has been added (see [1]) and kill switches
have been added to the GainController2 configuration in APM.
When `(sse2|neon)_allowed` is set to false, the corresponding SIMD code
path won't be used even if available.

Tested: appr.tc call made

[1] third_party/webrtc/modules/audio_processing/agc2/rnn_vad/vector_math.h

Bug: webrtc:7494
Change-Id: I2c10b09210914dfe8362c8d8b7fd434c6e4043fc
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/src/+/2620801Reviewed-by: Olga Sharonova <olka@chromium.org>
Commit-Queue: Ale Bzk <alessiob@chromium.org>
Cr-Commit-Position: refs/heads/master@{#842012}

third_party/blink/renderer/modules/mediastream/media_stream_audio_processor.cc

@@ -613,8 +613,12 @@ void MediaStreamAudioProcessor::InitializeAudioProcessingModule(
       agc2_properties->max_output_noise_level_dbfs =
           base::GetFieldTrialParamByFeatureAsInt(
               features::kWebRtcHybridAgc, "max_output_noise_level_dbfs", -50);
+      agc2_properties->sse2_allowed = base::GetFieldTrialParamByFeatureAsBool(
+          features::kWebRtcHybridAgc, "sse2_allowed", true);
       agc2_properties->avx2_allowed = base::GetFieldTrialParamByFeatureAsBool(
           features::kWebRtcHybridAgc, "avx2_allowed", true);
+      agc2_properties->neon_allowed = base::GetFieldTrialParamByFeatureAsBool(
+          features::kWebRtcHybridAgc, "neon_allowed", true);
     }
     blink::ConfigAutomaticGainControl(
         properties.goog_auto_gain_control,

third_party/blink/renderer/modules/mediastream/media_stream_audio_processor.h

@@ -122,7 +122,7 @@ class MODULES_EXPORT MediaStreamAudioProcessor
   FRIEND_TEST_ALL_PREFIXES(MediaStreamAudioProcessorTest,
                            TestAgcEnableHybridAgc);
   FRIEND_TEST_ALL_PREFIXES(MediaStreamAudioProcessorTest,
-                           TestAgcEnableHybridAgcAvx2NotAllowed);
+                           TestAgcEnableHybridAgcSimdNotAllowed);
 
   // WebRtcPlayoutDataSource::Sink implementation.
   void OnPlayoutData(media::AudioBus* audio_bus,

third_party/blink/renderer/modules/mediastream/media_stream_audio_processor_test.cc

@@ -434,7 +434,9 @@ TEST_F(MediaStreamAudioProcessorTest, TestAgcEnableHybridAgc) {
        {"gain_applier_speech_frames_threshold", "5"},
        {"max_gain_change_db_per_second", "4"},
        {"max_output_noise_level_dbfs", "-22"},
-       {"avx2_allowed", "true"}});
+       {"sse2_allowed", "true"},
+       {"avx2_allowed", "true"},
+       {"neon_allowed", "true"}});
 
   blink::AudioProcessingProperties properties;
   properties.goog_auto_gain_control = true;
@@ -475,13 +477,17 @@ TEST_F(MediaStreamAudioProcessorTest, TestAgcEnableHybridAgc) {
   EXPECT_EQ(adaptive_digital.gain_applier_adjacent_speech_frames_threshold, 5);
   EXPECT_FLOAT_EQ(adaptive_digital.max_gain_change_db_per_second, 4);
   EXPECT_FLOAT_EQ(adaptive_digital.max_output_noise_level_dbfs, -22);
+  EXPECT_TRUE(adaptive_digital.sse2_allowed);
   EXPECT_TRUE(adaptive_digital.avx2_allowed);
+  EXPECT_TRUE(adaptive_digital.neon_allowed);
 }
 
-TEST_F(MediaStreamAudioProcessorTest, TestAgcEnableHybridAgcAvx2NotAllowed) {
+TEST_F(MediaStreamAudioProcessorTest, TestAgcEnableHybridAgcSimdNotAllowed) {
   ::base::test::ScopedFeatureList feature_list;
   feature_list.InitAndEnableFeatureWithParameters(features::kWebRtcHybridAgc,
-                                                  {{"avx2_allowed", "false"}});
+                                                  {{"sse2_allowed", "false"},
+                                                   {"avx2_allowed", "false"},
+                                                   {"neon_allowed", "false"}});
 
   blink::AudioProcessingProperties properties;
   properties.goog_auto_gain_control = true;
@@ -497,7 +503,9 @@ TEST_F(MediaStreamAudioProcessorTest, TestAgcEnableHybridAgcAvx2NotAllowed) {
       audio_processor->GetAudioProcessingModuleConfig();
   ASSERT_TRUE(apm_config);
 
+  EXPECT_FALSE(apm_config->gain_controller2.adaptive_digital.sse2_allowed);
   EXPECT_FALSE(apm_config->gain_controller2.adaptive_digital.avx2_allowed);
+  EXPECT_FALSE(apm_config->gain_controller2.adaptive_digital.neon_allowed);
 }
 
 }  // namespace blink

third_party/blink/renderer/platform/mediastream/media_stream_audio_processor_options.cc

@@ -247,7 +247,9 @@ void ConfigAutomaticGainControl(
       adaptive_digital.max_output_noise_level_dbfs =
           agc2_properties->max_output_noise_level_dbfs;
 
+      adaptive_digital.sse2_allowed = agc2_properties->sse2_allowed;
       adaptive_digital.avx2_allowed = agc2_properties->avx2_allowed;
+      adaptive_digital.neon_allowed = agc2_properties->neon_allowed;
     }
   } else if (use_fixed_digital_agc2) {
     // Experimental AGC is disabled, thus hybrid AGC is disabled. Config AGC2

third_party/blink/renderer/platform/mediastream/media_stream_audio_processor_options.h

@@ -125,7 +125,9 @@ struct PLATFORM_EXPORT AdaptiveGainController2Properties {
   int gain_applier_speech_frames_threshold;
   int max_gain_change_db_per_second;
   int max_output_noise_level_dbfs;
+  bool sse2_allowed;
   bool avx2_allowed;
+  bool neon_allowed;
 };
 
 // Configures automatic gain control in `apm_config`. If `agc_enabled` is true

third_party/blink/renderer/platform/mediastream/media_stream_audio_processor_options_test.cc

@@ -51,7 +51,9 @@ TEST(ConfigAutomaticGainControlTest, EnableHybridAGC) {
   agc2_properties.gain_applier_speech_frames_threshold = 5;
   agc2_properties.max_gain_change_db_per_second = 4;
   agc2_properties.max_output_noise_level_dbfs = -22;
+  agc2_properties.sse2_allowed = true;
   agc2_properties.avx2_allowed = true;
+  agc2_properties.neon_allowed = true;
   const double compression_gain_db = 10.0;
 
   ConfigAutomaticGainControl(
@@ -89,7 +91,9 @@ TEST(ConfigAutomaticGainControlTest, EnableHybridAGC) {
                   agc2_properties.max_gain_change_db_per_second);
   EXPECT_FLOAT_EQ(adaptive_digital.max_output_noise_level_dbfs,
                   agc2_properties.max_output_noise_level_dbfs);
+  EXPECT_TRUE(adaptive_digital.sse2_allowed);
   EXPECT_TRUE(adaptive_digital.avx2_allowed);
+  EXPECT_TRUE(adaptive_digital.neon_allowed);
 }
 
 TEST(PopulateApmConfigTest, DefaultWithoutConfigJson) {