core refactoring (#69)

core/src/glwe_trace.rs

@@ -0,0 +1,102 @@
+use std::collections::HashMap;
+
+use backend::hal::layouts::{Backend, DataMut, DataRef, Module, Scratch};
+
+use crate::{
+    layouts::{GLWECiphertext, prepared::GGLWEAutomorphismKeyExec},
+    operations::GLWEOperations,
+};
+
+use crate::trait_families::{GLWETraceModuleFamily, GLWETraceScratchFamily};
+
+impl GLWECiphertext<Vec<u8>> {
+    pub fn trace_galois_elements<B: Backend>(module: &Module<B>) -> Vec<i64> {
+        let mut gal_els: Vec<i64> = Vec::new();
+        (0..module.log_n()).for_each(|i| {
+            if i == 0 {
+                gal_els.push(-1);
+            } else {
+                gal_els.push(module.galois_element(1 << (i - 1)));
+            }
+        });
+        gal_els
+    }
+
+    pub fn trace_scratch_space<B: Backend>(
+        module: &Module<B>,
+        n: usize,
+        basek: usize,
+        out_k: usize,
+        in_k: usize,
+        ksk_k: usize,
+        digits: usize,
+        rank: usize,
+    ) -> usize
+    where
+        Module<B>: GLWETraceModuleFamily<B>,
+    {
+        Self::automorphism_inplace_scratch_space(module, n, basek, out_k.min(in_k), ksk_k, digits, rank)
+    }
+
+    pub fn trace_inplace_scratch_space<B: Backend>(
+        module: &Module<B>,
+        n: usize,
+        basek: usize,
+        out_k: usize,
+        ksk_k: usize,
+        digits: usize,
+        rank: usize,
+    ) -> usize
+    where
+        Module<B>: GLWETraceModuleFamily<B>,
+    {
+        Self::automorphism_inplace_scratch_space(module, n, basek, out_k, ksk_k, digits, rank)
+    }
+}
+
+impl<DataSelf: DataMut> GLWECiphertext<DataSelf> {
+    pub fn trace<DataLhs: DataRef, DataAK: DataRef, B: Backend>(
+        &mut self,
+        module: &Module<B>,
+        start: usize,
+        end: usize,
+        lhs: &GLWECiphertext<DataLhs>,
+        auto_keys: &HashMap<i64, GGLWEAutomorphismKeyExec<DataAK, B>>,
+        scratch: &mut Scratch<B>,
+    ) where
+        Module<B>: GLWETraceModuleFamily<B>,
+        Scratch<B>: GLWETraceScratchFamily<B>,
+    {
+        self.copy(module, lhs);
+        self.trace_inplace(module, start, end, auto_keys, scratch);
+    }
+
+    pub fn trace_inplace<DataAK: DataRef, B: Backend>(
+        &mut self,
+        module: &Module<B>,
+        start: usize,
+        end: usize,
+        auto_keys: &HashMap<i64, GGLWEAutomorphismKeyExec<DataAK, B>>,
+        scratch: &mut Scratch<B>,
+    ) where
+        Module<B>: GLWETraceModuleFamily<B>,
+        Scratch<B>: GLWETraceScratchFamily<B>,
+    {
+        (start..end).for_each(|i| {
+            self.rsh(module, 1);
+
+            let p: i64;
+            if i == 0 {
+                p = -1;
+            } else {
+                p = module.galois_element(1 << (i - 1));
+            }
+
+            if let Some(key) = auto_keys.get(&p) {
+                self.automorphism_add_inplace(module, key, scratch);
+            } else {
+                panic!("auto_keys[{}] is empty", p)
+            }
+        });
+    }
+}