diff --git a/libavcodec/x86/idctdsp.h b/libavcodec/x86/idctdsp.h
index 738e4e36e4..9e8474cacd 100644
--- a/libavcodec/x86/idctdsp.h
+++ b/libavcodec/x86/idctdsp.h
@@ -22,11 +22,11 @@
 #include <stddef.h>
 #include <stdint.h>
 
-void ff_add_pixels_clamped_sse2(const int16_t *block, uint8_t *pixels,
+void ff_add_pixels_clamped_sse2(const int16_t *block, uint8_t *restrict pixels,
                                 ptrdiff_t line_size);
-void ff_put_pixels_clamped_sse2(const int16_t *block, uint8_t *pixels,
+void ff_put_pixels_clamped_sse2(const int16_t *block, uint8_t *restrict pixels,
                                 ptrdiff_t line_size);
-void ff_put_signed_pixels_clamped_sse2(const int16_t *block, uint8_t *pixels,
+void ff_put_signed_pixels_clamped_sse2(const int16_t *block, uint8_t *restrict pixels,
                                        ptrdiff_t line_size);