Fix the panic subgroup_fft_in_place benchmark for MNT6-753's Fr

CHANGELOG.md

@@ -15,6 +15,7 @@
 
 ### Bug fixes
 - [\#252](https://github.com/arkworks-rs/algebra/pull/252) (ark-ff) Fix prime field sampling when `REPR_SHIFT_BITS` is 64.
+- [\#284](https://github.com/arkworks-rs/algebra/pull/284) (ark-poly-benches) Fix the panic `subgroup_fft_in_place` benchmark for MNT6-753's Fr.
 
 
 ## v0.2.0

poly-benches/benches/fft.rs

@@ -12,7 +12,8 @@ use criterion::{criterion_group, criterion_main, Bencher, Criterion};
 // degree bounds to benchmark on
 // e.g. degree bound of 2^{15}, means we do an FFT for a degree (2^{15} - 1) polynomial
 const BENCHMARK_MIN_DEGREE: usize = 1 << 15;
-const BENCHMARK_MAX_DEGREE: usize = 1 << 22;
+const BENCHMARK_MAX_DEGREE_BLS12_381: usize = 1 << 22;
+const BENCHMARK_MAX_DEGREE_MNT6_753: usize = 1 << 17;
 const BENCHMARK_LOG_INTERVAL_DEGREE: usize = 1;
 
 const ENABLE_RADIX2_BENCHES: bool = true;
@@ -22,17 +23,30 @@ const ENABLE_MIXED_RADIX_BENCHES: bool = true;
 // interval = BENCHMARK_LOG_INTERVAL_DEGREE
 // min      = ceil(log_2(BENCHMARK_MIN_DEGREE))
 // max      = ceil(log_2(BENCHMARK_MAX_DEGREE))
-fn default_size_range() -> Vec<usize> {
+fn default_size_range_bls12_381() -> Vec<usize> {
     size_range(
         BENCHMARK_LOG_INTERVAL_DEGREE,
         BENCHMARK_MIN_DEGREE,
-        BENCHMARK_MAX_DEGREE,
+        BENCHMARK_MAX_DEGREE_BLS12_381,
     )
 }
 
-fn setup_bench(c: &mut Criterion, name: &str, bench_fn: fn(&mut Bencher, &usize)) {
+fn default_size_range_mnt6_753() -> Vec<usize> {
+    size_range(
+        BENCHMARK_LOG_INTERVAL_DEGREE,
+        BENCHMARK_MIN_DEGREE,
+        BENCHMARK_MAX_DEGREE_MNT6_753,
+    )
+}
+
+fn setup_bench(
+    c: &mut Criterion,
+    name: &str,
+    bench_fn: fn(&mut Bencher, &usize),
+    size_range: &[usize],
+) {
     let mut group = c.benchmark_group(name);
-    for degree in default_size_range().iter() {
+    for degree in size_range.iter() {
         group.bench_with_input(BenchmarkId::from_parameter(degree), degree, bench_fn);
     }
     group.finish();
@@ -83,28 +97,40 @@ fn bench_coset_ifft_in_place<F: FftField, D: EvaluationDomain<F>>(b: &mut Benche
     });
 }
 
-fn fft_benches<F: FftField, D: EvaluationDomain<F>>(c: &mut Criterion, name: &'static str) {
+fn fft_benches<F: FftField, D: EvaluationDomain<F>>(
+    c: &mut Criterion,
+    name: &'static str,
+    size_range: &[usize],
+) {
     let cur_name = format!("{:?} - subgroup_fft_in_place", name.clone());
-    setup_bench(c, &cur_name, bench_fft_in_place::<F, D>);
+    setup_bench(c, &cur_name, bench_fft_in_place::<F, D>, size_range);
     let cur_name = format!("{:?} - subgroup_ifft_in_place", name.clone());
-    setup_bench(c, &cur_name, bench_ifft_in_place::<F, D>);
+    setup_bench(c, &cur_name, bench_ifft_in_place::<F, D>, size_range);
     let cur_name = format!("{:?} - coset_fft_in_place", name.clone());
-    setup_bench(c, &cur_name, bench_coset_fft_in_place::<F, D>);
+    setup_bench(c, &cur_name, bench_coset_fft_in_place::<F, D>, size_range);
     let cur_name = format!("{:?} - coset_ifft_in_place", name.clone());
-    setup_bench(c, &cur_name, bench_coset_ifft_in_place::<F, D>);
+    setup_bench(c, &cur_name, bench_coset_ifft_in_place::<F, D>, size_range);
 }
 
 fn bench_bls12_381(c: &mut Criterion) {
     let name = "bls12_381 - radix2";
     if ENABLE_RADIX2_BENCHES {
-        fft_benches::<bls12_381_fr, Radix2EvaluationDomain<bls12_381_fr>>(c, name);
+        fft_benches::<bls12_381_fr, Radix2EvaluationDomain<bls12_381_fr>>(
+            c,
+            name,
+            &default_size_range_bls12_381(),
+        );
     }
 }
 
 fn bench_mnt6_753(c: &mut Criterion) {
     let name = "mnt6_753 - mixed radix";
     if ENABLE_MIXED_RADIX_BENCHES {
-        fft_benches::<mnt6_753_fr, MixedRadixEvaluationDomain<mnt6_753_fr>>(c, name);
+        fft_benches::<mnt6_753_fr, MixedRadixEvaluationDomain<mnt6_753_fr>>(
+            c,
+            name,
+            &default_size_range_mnt6_753(),
+        );
     }
 }