diff --git a/webrtc/common_audio/signal_processing/include/spl_inl.h b/webrtc/common_audio/signal_processing/include/spl_inl.h
index d3cc6dee6c..3c0a81cf34 100644
--- a/webrtc/common_audio/signal_processing/include/spl_inl.h
+++ b/webrtc/common_audio/signal_processing/include/spl_inl.h
@@ -35,42 +35,32 @@ static __inline int16_t WebRtcSpl_SatW32ToW16(int32_t value32) {
   return out16;
 }
 
-static __inline int32_t WebRtcSpl_AddSatW32(int32_t l_var1, int32_t l_var2) {
-  int32_t l_sum;
+static __inline int32_t WebRtcSpl_AddSatW32(int32_t a, int32_t b) {
+  // Do the addition in unsigned numbers, since signed overflow is undefined
+  // behavior.
+  const int32_t sum = (int32_t)((uint32_t)a + (uint32_t)b);
 
-  // Perform long addition
-  l_sum = l_var1 + l_var2;
-
-  if (l_var1 < 0) {  // Check for underflow.
-    if ((l_var2 < 0) && (l_sum >= 0)) {
-        l_sum = (int32_t)0x80000000;
-    }
-  } else {  // Check for overflow.
-    if ((l_var2 > 0) && (l_sum < 0)) {
-        l_sum = (int32_t)0x7FFFFFFF;
-    }
+  // a + b can't overflow if a and b have different signs. If they have the
+  // same sign, a + b also has the same sign iff it didn't overflow.
+  if ((a < 0) == (b < 0) && (a < 0) != (sum < 0)) {
+    // The direction of the overflow is obvious from the sign of a + b.
+    return sum < 0 ? INT32_MAX : INT32_MIN;
   }
-
-  return l_sum;
+  return sum;
 }
 
-static __inline int32_t WebRtcSpl_SubSatW32(int32_t l_var1, int32_t l_var2) {
-  int32_t l_diff;
+static __inline int32_t WebRtcSpl_SubSatW32(int32_t a, int32_t b) {
+  // Do the subtraction in unsigned numbers, since signed overflow is undefined
+  // behavior.
+  const int32_t diff = (int32_t)((uint32_t)a - (uint32_t)b);
 
-  // Perform subtraction.
-  l_diff = l_var1 - l_var2;
-
-  if (l_var1 < 0) {  // Check for underflow.
-    if ((l_var2 > 0) && (l_diff > 0)) {
-      l_diff = (int32_t)0x80000000;
-    }
-  } else {  // Check for overflow.
-    if ((l_var2 < 0) && (l_diff < 0)) {
-      l_diff = (int32_t)0x7FFFFFFF;
-    }
+  // a - b can't overflow if a and b have the same sign. If they have different
+  // signs, a - b has the same sign as a iff it didn't overflow.
+  if ((a < 0) != (b < 0) && (a < 0) != (diff < 0)) {
+    // The direction of the overflow is obvious from the sign of a - b.
+    return diff < 0 ? INT32_MAX : INT32_MIN;
   }
-
-  return l_diff;
+  return diff;
 }
 
 static __inline int16_t WebRtcSpl_AddSatW16(int16_t a, int16_t b) {
diff --git a/webrtc/common_audio/signal_processing/signal_processing_unittest.cc b/webrtc/common_audio/signal_processing/signal_processing_unittest.cc
index 108f459c89..0dc0d37878 100644
--- a/webrtc/common_audio/signal_processing/signal_processing_unittest.cc
+++ b/webrtc/common_audio/signal_processing/signal_processing_unittest.cc
@@ -8,6 +8,9 @@
  *  be found in the AUTHORS file in the root of the source tree.
  */
 
+#include <algorithm>
+#include <sstream>
+
 #include "testing/gtest/include/gtest/gtest.h"
 #include "webrtc/common_audio/signal_processing/include/signal_processing_library.h"
 
@@ -118,26 +121,25 @@ TEST_F(SplTest, InlineTest) {
 
     EXPECT_EQ(104, WebRtcSpl_AddSatW16(a16, b16));
     EXPECT_EQ(138, WebRtcSpl_SubSatW16(a16, b16));
+}
 
-    EXPECT_EQ(109410, WebRtcSpl_AddSatW32(a32, b32));
-    EXPECT_EQ(112832, WebRtcSpl_SubSatW32(a32, b32));
-
-    a32 = 0x80000000;
-    b32 = 0x80000000;
-    // Cast to signed int to avoid compiler complaint on gtest.h.
-    EXPECT_EQ(static_cast<int>(0x80000000), WebRtcSpl_AddSatW32(a32, b32));
-    a32 = 0x7fffffff;
-    b32 = 0x7fffffff;
-    EXPECT_EQ(0x7fffffff, WebRtcSpl_AddSatW32(a32, b32));
-    a32 = 0;
-    b32 = 0x80000000;
-    EXPECT_EQ(0x7fffffff, WebRtcSpl_SubSatW32(a32, b32));
-    a32 = 0x7fffffff;
-    b32 = 0x80000000;
-    EXPECT_EQ(0x7fffffff, WebRtcSpl_SubSatW32(a32, b32));
-    a32 = 0x80000000;
-    b32 = 0x7fffffff;
-    EXPECT_EQ(static_cast<int>(0x80000000), WebRtcSpl_SubSatW32(a32, b32));
+TEST_F(SplTest, AddSubSatW32) {
+  static constexpr int32_t kAddSubArgs[] = {
+      INT32_MIN, INT32_MIN + 1, -3,       -2, -1, 0, 1, -1, 2,
+      3,         INT32_MAX - 1, INT32_MAX};
+  for (int32_t a : kAddSubArgs) {
+    for (int32_t b : kAddSubArgs) {
+      const int64_t sum = std::max<int64_t>(
+          INT32_MIN, std::min<int64_t>(INT32_MAX, static_cast<int64_t>(a) + b));
+      const int64_t diff = std::max<int64_t>(
+          INT32_MIN, std::min<int64_t>(INT32_MAX, static_cast<int64_t>(a) - b));
+      std::ostringstream ss;
+      ss << a << " +/- " << b << ": sum " << sum << ", diff " << diff;
+      SCOPED_TRACE(ss.str());
+      EXPECT_EQ(sum, WebRtcSpl_AddSatW32(a, b));
+      EXPECT_EQ(diff, WebRtcSpl_SubSatW32(a, b));
+    }
+  }
 }
 
 TEST_F(SplTest, MathOperationsTest) {