Backend refactor (#120)

* remove spqlios, split cpu_ref and cpu_avx into different crates

* remove spqlios submodule

* update crate naming & add avx tests

poulpy-cpu-ref/benches/fft.rs

@@ -0,0 +1,64 @@
+use std::hint::black_box;
+
+use criterion::{BenchmarkId, Criterion, criterion_group, criterion_main};
+use poulpy_hal::reference::fft64::reim::{ReimDFTExecute, ReimFFTRef, ReimFFTTable, ReimIFFTRef, ReimIFFTTable};
+
+pub fn bench_fft_ref(c: &mut Criterion) {
+    let group_name: String = "fft_ref".to_string();
+
+    let mut group = c.benchmark_group(group_name);
+
+    fn runner(m: usize) -> impl FnMut() {
+        let mut values: Vec<f64> = vec![0f64; m << 1];
+        let scale: f64 = 1.0f64 / (2 * m) as f64;
+        values
+            .iter_mut()
+            .enumerate()
+            .for_each(|(i, x)| *x = (i + 1) as f64 * scale);
+        let table: ReimFFTTable<f64> = ReimFFTTable::<f64>::new(m);
+        move || {
+            ReimFFTRef::reim_dft_execute(&table, &mut values);
+            black_box(());
+        }
+    }
+
+    for log_m in [9, 10, 11, 12, 13, 14, 15] {
+        let id: BenchmarkId = BenchmarkId::from_parameter(format!("n: {}", 2 << log_m));
+        let mut runner = runner(1 << log_m);
+        group.bench_with_input(id, &(), |b, _| b.iter(&mut runner));
+    }
+
+    group.finish();
+}
+
+pub fn bench_ifft_ref(c: &mut Criterion) {
+    let group_name: String = "ifft_ref".to_string();
+
+    let mut group = c.benchmark_group(group_name);
+
+    fn runner(m: usize) -> impl FnMut() {
+        let mut values: Vec<f64> = vec![0f64; m << 1];
+        let scale: f64 = 1.0f64 / (2 * m) as f64;
+        values
+            .iter_mut()
+            .enumerate()
+            .for_each(|(i, x)| *x = (i + 1) as f64 * scale);
+        let table: ReimIFFTTable<f64> = ReimIFFTTable::<f64>::new(m);
+        move || {
+            ReimIFFTRef::reim_dft_execute(&table, &mut values);
+            black_box(());
+        }
+    }
+
+    for log_m in [9, 10, 11, 12, 13, 14, 15] {
+        let id: BenchmarkId = BenchmarkId::from_parameter(format!("n: {}", 2 << log_m));
+        let mut runner = runner(1 << log_m);
+        group.bench_with_input(id, &(), |b, _| b.iter(&mut runner));
+    }
+
+    group.finish();
+}
+
+criterion_group!(benches, bench_fft_ref, bench_ifft_ref,);
+
+criterion_main!(benches);