diff --git a/src/dsp/cost.c b/src/dsp/cost.c
index 73d21401..609f9264 100644
--- a/src/dsp/cost.c
+++ b/src/dsp/cost.c
@@ -354,8 +354,8 @@ static int GetResidualCost_C(int ctx0, const VP8Residual* const res) {
   return cost;
 }
 
-static void SetResidualCoeffs_C(const int16_t* const coeffs,
-                                VP8Residual* const res) {
+static void SetResidualCoeffs_C(const int16_t* WEBP_RESTRICT const coeffs,
+                                VP8Residual* WEBP_RESTRICT const res) {
   int n;
   res->last = -1;
   assert(res->first == 0 || coeffs[0] == 0);
diff --git a/src/dsp/cost_mips32.c b/src/dsp/cost_mips32.c
index 0500f88c..54586576 100644
--- a/src/dsp/cost_mips32.c
+++ b/src/dsp/cost_mips32.c
@@ -96,8 +96,8 @@ static int GetResidualCost_MIPS32(int ctx0, const VP8Residual* const res) {
   return cost;
 }
 
-static void SetResidualCoeffs_MIPS32(const int16_t* const coeffs,
-                                     VP8Residual* const res) {
+static void SetResidualCoeffs_MIPS32(const int16_t* WEBP_RESTRICT const coeffs,
+                                     VP8Residual* WEBP_RESTRICT const res) {
   const int16_t* p_coeffs = (int16_t*)coeffs;
   int temp0, temp1, temp2, n, n1;
   assert(res->first == 0 || coeffs[0] == 0);
diff --git a/src/dsp/cost_neon.c b/src/dsp/cost_neon.c
index 6582669c..e1bf3657 100644
--- a/src/dsp/cost_neon.c
+++ b/src/dsp/cost_neon.c
@@ -19,8 +19,8 @@
 static const uint8_t position[16] = { 1, 2,  3,  4,  5,  6,  7,  8,
                                       9, 10, 11, 12, 13, 14, 15, 16 };
 
-static void SetResidualCoeffs_NEON(const int16_t* const coeffs,
-                                   VP8Residual* const res) {
+static void SetResidualCoeffs_NEON(const int16_t* WEBP_RESTRICT const coeffs,
+                                   VP8Residual* WEBP_RESTRICT const res) {
   const int16x8_t minus_one = vdupq_n_s16(-1);
   const int16x8_t coeffs_0 = vld1q_s16(coeffs);
   const int16x8_t coeffs_1 = vld1q_s16(coeffs + 8);
diff --git a/src/dsp/cost_sse2.c b/src/dsp/cost_sse2.c
index 487a0799..a869b48d 100644
--- a/src/dsp/cost_sse2.c
+++ b/src/dsp/cost_sse2.c
@@ -22,8 +22,8 @@
 
 //------------------------------------------------------------------------------
 
-static void SetResidualCoeffs_SSE2(const int16_t* const coeffs,
-                                   VP8Residual* const res) {
+static void SetResidualCoeffs_SSE2(const int16_t* WEBP_RESTRICT const coeffs,
+                                   VP8Residual* WEBP_RESTRICT const res) {
   const __m128i c0 = _mm_loadu_si128((const __m128i*)(coeffs + 0));
   const __m128i c1 = _mm_loadu_si128((const __m128i*)(coeffs + 8));
   // Use SSE2 to compare 16 values with a single instruction.
diff --git a/src/dsp/dsp.h b/src/dsp/dsp.h
index 23bc2965..82029533 100644
--- a/src/dsp/dsp.h
+++ b/src/dsp/dsp.h
@@ -138,8 +138,9 @@ extern const uint16_t VP8LevelFixedCosts[2047 /*MAX_LEVEL*/ + 1];
 extern const uint8_t VP8EncBands[16 + 1];
 
 struct VP8Residual;
-typedef void (*VP8SetResidualCoeffsFunc)(const int16_t* const coeffs,
-                                         struct VP8Residual* const res);
+typedef void (*VP8SetResidualCoeffsFunc)(
+    const int16_t* WEBP_RESTRICT const coeffs,
+    struct VP8Residual* WEBP_RESTRICT const res);
 extern VP8SetResidualCoeffsFunc VP8SetResidualCoeffs;
 
 // Cost calculation function.