Unused frame_sort.
Unused x86_64 dequant_4x4dc_mmx2, predict_8x8_vr_mmx2.
Unused and broken high_depth integral_init*h_sse4, optimize_chroma_*, dequant_flat_*, sub8x8_dct_dc_*, zigzag_sub_*.
Useless high_depth dequant_sse4, dequant_dc_sse4.