diff --git a/build/moz.configure/toolchain.configure b/build/moz.configure/toolchain.configure
index ba3e36903724..dd388e44252f 100644
--- a/build/moz.configure/toolchain.configure
+++ b/build/moz.configure/toolchain.configure
@@ -3091,3 +3091,5 @@ set_config("MMX_FLAGS", ["-mmmx"])
 set_config("SSE_FLAGS", ["-msse"])
 set_config("SSE2_FLAGS", ["-msse2"])
 set_config("SSSE3_FLAGS", ["-mssse3"])
+set_config("SSE4_2_FLAGS", ["-msse4.2"])
+set_config("FMA_FLAGS", ["-mfma"])
diff --git a/dom/media/webaudio/AudioNodeEngine.cpp b/dom/media/webaudio/AudioNodeEngine.cpp
index ede0560e99e6..75f0edde97e9 100644
--- a/dom/media/webaudio/AudioNodeEngine.cpp
+++ b/dom/media/webaudio/AudioNodeEngine.cpp
@@ -15,6 +15,10 @@
 #  include "mozilla/SSE.h"
 #  include "AudioNodeEngineGeneric.h"
 #endif
+#if defined(USE_SSE42) && defined(USE_FMA3)
+#  include "mozilla/SSE.h"
+#  include "AudioNodeEngineGeneric.h"
+#endif
 #include "AudioBlock.h"
 #include "Tracing.h"
 
@@ -74,8 +78,16 @@ void AudioBufferAddWithScale(const float* aInput, float aScale, float* aOutput,
 
 #ifdef USE_SSE2
   if (mozilla::supports_sse2()) {
-    Engine<xsimd::sse2>::AudioBufferAddWithScale(aInput, aScale, aOutput,
-                                                 aSize);
+#  if defined(USE_SSE42) && defined(USE_FMA3)
+    if (mozilla::supports_fma3() && mozilla::supports_sse4_2()) {
+      Engine<xsimd::fma3<xsimd::sse4_2>>::AudioBufferAddWithScale(
+          aInput, aScale, aOutput, aSize);
+    } else
+#  endif
+    {
+      Engine<xsimd::sse2>::AudioBufferAddWithScale(aInput, aScale, aOutput,
+                                                   aSize);
+    }
     return;
   }
 #endif
@@ -134,7 +146,16 @@ void BufferComplexMultiply(const float* aInput, const float* aScale,
 #endif
 #ifdef USE_SSE2
   if (mozilla::supports_sse()) {
-    Engine<xsimd::sse2>::BufferComplexMultiply(aInput, aScale, aOutput, aSize);
+#  if defined(USE_SSE42) && defined(USE_FMA3)
+    if (mozilla::supports_fma3() && mozilla::supports_sse4_2()) {
+      Engine<xsimd::fma3<xsimd::sse4_2>>::BufferComplexMultiply(aInput, aScale,
+                                                                aOutput, aSize);
+    } else
+#  endif
+    {
+      Engine<xsimd::sse2>::BufferComplexMultiply(aInput, aScale, aOutput,
+                                                 aSize);
+    }
     return;
   }
 #endif
@@ -270,8 +291,16 @@ void AudioBlockPanStereoToStereo(const float aInputL[WEBAUDIO_BLOCK_SIZE],
 
 #ifdef USE_SSE2
   if (mozilla::supports_sse2()) {
-    Engine<xsimd::sse2>::AudioBlockPanStereoToStereo(
-        aInputL, aInputR, aGainL, aGainR, aIsOnTheLeft, aOutputL, aOutputR);
+#  if defined(USE_SSE42) && defined(USE_FMA3)
+    if (mozilla::supports_fma3() && mozilla::supports_sse4_2()) {
+      Engine<xsimd::fma3<xsimd::sse4_2>>::AudioBlockPanStereoToStereo(
+          aInputL, aInputR, aGainL, aGainR, aIsOnTheLeft, aOutputL, aOutputR);
+    } else
+#  endif
+    {
+      Engine<xsimd::sse2>::AudioBlockPanStereoToStereo(
+          aInputL, aInputR, aGainL, aGainR, aIsOnTheLeft, aOutputL, aOutputR);
+    }
     return;
   }
 #endif
@@ -308,8 +337,16 @@ void AudioBlockPanStereoToStereo(const float aInputL[WEBAUDIO_BLOCK_SIZE],
 
 #ifdef USE_SSE2
   if (mozilla::supports_sse2()) {
-    Engine<xsimd::sse2>::AudioBlockPanStereoToStereo(
-        aInputL, aInputR, aGainL, aGainR, aIsOnTheLeft, aOutputL, aOutputR);
+#  if defined(USE_SSE42) && defined(USE_FMA3)
+    if (mozilla::supports_fma3() && mozilla::supports_sse4_2()) {
+      Engine<xsimd::fma3<xsimd::sse2>>::AudioBlockPanStereoToStereo(
+          aInputL, aInputR, aGainL, aGainR, aIsOnTheLeft, aOutputL, aOutputR);
+    } else
+#  endif
+    {
+      Engine<xsimd::sse2>::AudioBlockPanStereoToStereo(
+          aInputL, aInputR, aGainL, aGainR, aIsOnTheLeft, aOutputL, aOutputR);
+    }
     return;
   }
 #endif
@@ -335,7 +372,15 @@ float AudioBufferSumOfSquares(const float* aInput, uint32_t aLength) {
 
 #ifdef USE_SSE2
   if (mozilla::supports_sse()) {
-    return Engine<xsimd::sse2>::AudioBufferSumOfSquares(aInput, aLength);
+#  if defined(USE_SSE42) && defined(USE_FMA3)
+    if (mozilla::supports_fma3() && mozilla::supports_sse4_2()) {
+      return Engine<xsimd::fma3<xsimd::sse4_2>>::AudioBufferSumOfSquares(
+          aInput, aLength);
+    } else
+#  endif
+    {
+      return Engine<xsimd::sse2>::AudioBufferSumOfSquares(aInput, aLength);
+    }
   }
 #endif
 
diff --git a/dom/media/webaudio/AudioNodeEngineSSE4_2_FMA3.cpp b/dom/media/webaudio/AudioNodeEngineSSE4_2_FMA3.cpp
new file mode 100644
index 000000000000..53636f0193a0
--- /dev/null
+++ b/dom/media/webaudio/AudioNodeEngineSSE4_2_FMA3.cpp
@@ -0,0 +1,10 @@
+/* -*- mode: c++; tab-width: 2; indent-tabs-mode: nil; c-basic-offset: 2 -*- */
+/* this source code form is subject to the terms of the mozilla public
+ * license, v. 2.0. if a copy of the mpl was not distributed with this file,
+ * You can obtain one at http://mozilla.org/MPL/2.0/. */
+
+#include "AudioNodeEngineGeneric.h"
+
+namespace mozilla {
+template struct Engine<xsimd::fma3<xsimd::sse4_2>>;
+}  // namespace mozilla
diff --git a/dom/media/webaudio/moz.build b/dom/media/webaudio/moz.build
index 7148a56a086c..54805556ffd4 100644
--- a/dom/media/webaudio/moz.build
+++ b/dom/media/webaudio/moz.build
@@ -133,12 +133,17 @@ if CONFIG["CPU_ARCH"] == "aarch64" or CONFIG["BUILD_ARM_NEON"]:
     if CONFIG["BUILD_ARM_NEON"]:
         LOCAL_INCLUDES += ["/media/openmax_dl/dl/api/"]
 
-# Are we targeting x86 or x64?  If so, build SSE2 files.
+# Are we targeting x86 or x64?  If so, build SSEX files.
 if CONFIG["INTEL_ARCHITECTURE"]:
-    SOURCES += ["AudioNodeEngineSSE2.cpp"]
+    SOURCES += ["AudioNodeEngineSSE2.cpp", "AudioNodeEngineSSE4_2_FMA3.cpp"]
     DEFINES["USE_SSE2"] = True
+    DEFINES["USE_SSE4_2"] = True
+    DEFINES["USE_FMA3"] = True
     LOCAL_INCLUDES += ["/third_party/xsimd/include"]
     SOURCES["AudioNodeEngineSSE2.cpp"].flags += CONFIG["SSE2_FLAGS"]
+    SOURCES["AudioNodeEngineSSE4_2_FMA3.cpp"].flags += (
+        CONFIG["SSE4_2_FLAGS"] + CONFIG["FMA_FLAGS"]
+    )
 
 include("/ipc/chromium/chromium-config.mozbuild")
 
diff --git a/mozglue/misc/SSE.cpp b/mozglue/misc/SSE.cpp
index e15f666bc0c4..ca0b4c3c86de 100644
--- a/mozglue/misc/SSE.cpp
+++ b/mozglue/misc/SSE.cpp
@@ -147,6 +147,10 @@ bool sse4_1_enabled = has_cpuid_bits(1u, ecx, (1u << 19));
 bool sse4_2_enabled = has_cpuid_bits(1u, ecx, (1u << 20));
 #  endif
 
+#  if !defined(MOZILLA_PRESUME_FMA3)
+bool fma3_enabled = has_cpuid_bits(1u, ecx, (1u << 12));
+#  endif
+
 #  if !defined(MOZILLA_PRESUME_AVX) || !defined(MOZILLA_PRESUME_AVX2)
 static bool has_avx() {
 #    if defined(MOZILLA_PRESUME_AVX)
diff --git a/mozglue/misc/SSE.h b/mozglue/misc/SSE.h
index 29a312fc7ebd..0b87366a8043 100644
--- a/mozglue/misc/SSE.h
+++ b/mozglue/misc/SSE.h
@@ -215,6 +215,9 @@ extern bool MFBT_DATA sse4_1_enabled;
 #  if !defined(MOZILLA_PRESUME_SSE4_2)
 extern bool MFBT_DATA sse4_2_enabled;
 #  endif
+#  if !defined(MOZILLA_PRESUME_FMA3)
+extern bool MFBT_DATA fma3_enabled;
+#  endif
 #  if !defined(MOZILLA_PRESUME_AVX)
 extern bool MFBT_DATA avx_enabled;
 #  endif
@@ -317,6 +320,16 @@ inline bool supports_sse4_2() { return sse_private::sse4_2_enabled; }
 inline bool supports_sse4_2() { return false; }
 #endif
 
+#if defined(MOZILLA_PRESUME_FMA3)
+#  define MOZILLA_MAY_SUPPORT_FMA3 1
+inline bool supports_fma3() { return true; }
+#elif defined(MOZILLA_SSE_HAVE_CPUID_DETECTION)
+#  define MOZILLA_MAY_SUPPORT_FMA3 1
+inline bool supports_fma3() { return sse_private::fma3_enabled; }
+#else
+inline bool supports_fma3() { return false; }
+#endif
+
 #if defined(MOZILLA_PRESUME_AVX)
 #  define MOZILLA_MAY_SUPPORT_AVX 1
 inline bool supports_avx() { return true; }