Add benchmarks for motion_compensate function

This was identified as a hot function, so a benchmark will help us to
optimize it.

benches/bench.rs

@@ -219,5 +219,5 @@ criterion_main!(
   ec,
   rdo,
   plane,
-  mc::mc
+  mc::mc,
 );

benches/mc.rs

@@ -3,11 +3,20 @@
 use criterion::*;
 use rand::{Rng, SeedableRng};
 use rand_chacha::ChaChaRng;
+use rav1e::bench::context::BlockContext;
+use rav1e::bench::context::CDFContext;
+use rav1e::bench::context::ContextWriter;
+use rav1e::bench::context::FrameBlocks;
 use rav1e::bench::cpu_features::*;
+use rav1e::bench::encoder::FrameState;
+use rav1e::bench::encoder::{motion_compensate, FrameInvariants};
 use rav1e::bench::frame::{AsRegion, PlaneOffset, PlaneSlice};
 use rav1e::bench::mc::*;
+use rav1e::bench::partition::RefType;
 use rav1e::bench::util::Aligned;
+use rav1e::context::{BlockOffset, TileBlockOffset};
 use rav1e::prelude::*;
+use std::sync::Arc;
 
 fn bench_put_8tap_top_left_lbd(c: &mut Criterion) {
   let mut ra = ChaChaRng::from_seed([0; 32]);
@@ -505,6 +514,76 @@ fn bench_prep_8tap_center_hbd(c: &mut Criterion) {
   });
 }
 
+fn bench_motion_compensate(c: &mut Criterion) {
+  let config = Arc::new(EncoderConfig {
+    width: 640,
+    height: 480,
+    bit_depth: 8,
+    speed_settings: SpeedSettings::from_preset(2),
+    ..Default::default()
+  });
+  let sequence = Arc::new(Sequence::new(&Default::default()));
+  let fi = FrameInvariants::<u8>::new(config, sequence);
+  let mut fc = CDFContext::new(fi.base_q_idx);
+  let mut fb = FrameBlocks::new(fi.sb_width * 16, fi.sb_height * 16);
+  let mut tb = fb.as_tile_blocks_mut();
+  let bc = BlockContext::new(&mut tb);
+  let mut fs = FrameState::new(&fi);
+  let mut cw = ContextWriter::new(&mut fc, bc);
+  fs.apply_tile_state_mut(|ts| {
+    c.bench_function("motion_compensate", |b| {
+      b.iter(|| {
+        let _ = black_box(motion_compensate(
+          &fi,
+          ts,
+          &mut cw,
+          PredictionMode::NEARESTMV,
+          [RefType::LAST_FRAME, RefType::ALTREF_FRAME],
+          [MotionVector { row: 4, col: 4 }, MotionVector { row: 2, col: 2 }],
+          BlockSize::BLOCK_8X8,
+          TileBlockOffset(BlockOffset { x: 3, y: 3 }),
+          false,
+        ));
+      })
+    });
+  });
+}
+
+fn bench_motion_compensate_hbd(c: &mut Criterion) {
+  let config = Arc::new(EncoderConfig {
+    width: 640,
+    height: 480,
+    bit_depth: 10,
+    speed_settings: SpeedSettings::from_preset(2),
+    ..Default::default()
+  });
+  let sequence = Arc::new(Sequence::new(&Default::default()));
+  let fi = FrameInvariants::<u16>::new(config, sequence);
+  let mut fc = CDFContext::new(fi.base_q_idx);
+  let mut fb = FrameBlocks::new(fi.sb_width * 16, fi.sb_height * 16);
+  let mut tb = fb.as_tile_blocks_mut();
+  let bc = BlockContext::new(&mut tb);
+  let mut fs = FrameState::new(&fi);
+  let mut cw = ContextWriter::new(&mut fc, bc);
+  fs.apply_tile_state_mut(|ts| {
+    c.bench_function("motion_compensate_hbd", |b| {
+      b.iter(|| {
+        let _ = black_box(motion_compensate(
+          &fi,
+          ts,
+          &mut cw,
+          PredictionMode::NEARESTMV,
+          [RefType::LAST_FRAME, RefType::ALTREF_FRAME],
+          [MotionVector { row: 4, col: 4 }, MotionVector { row: 2, col: 2 }],
+          BlockSize::BLOCK_8X8,
+          TileBlockOffset(BlockOffset { x: 3, y: 3 }),
+          false,
+        ));
+      })
+    });
+  });
+}
+
 criterion_group!(
   mc,
   bench_put_8tap_top_left_lbd,
@@ -522,7 +601,9 @@ criterion_group!(
   bench_prep_8tap_top_left_hbd,
   bench_prep_8tap_top_hbd,
   bench_prep_8tap_left_hbd,
-  bench_prep_8tap_center_hbd
+  bench_prep_8tap_center_hbd,
+  bench_motion_compensate,
+  bench_motion_compensate_hbd,
 );
 
 fn fill_plane<T: Pixel>(ra: &mut ChaChaRng, plane: &mut Plane<T>) {