chore!: use u64 for shortint metadata

This switches from usize to u64 for shortint's metdata:
* Degree
* MaxDegree
* CarryModulus
* MessageModulus

The reasoning is that usize should be preferred when the value is used
as some kind of index, memory access, etc, and not numbers like these
metadata are.

This is a breaking API change
This is also a somewhat breaking serialization change
depending on the serialization format (bincode should be ok as it
encodes usize as u64)

tfhe/benches/shortint/bench.rs

@@ -94,7 +94,7 @@ fn bench_server_key_unary_function<F>(
 
         let mut rng = rand::thread_rng();
 
-        let modulus = cks.parameters.message_modulus().0 as u64;
+        let modulus = cks.parameters.message_modulus().0;
 
         let clear_text = rng.gen::<u64>() % modulus;
 
@@ -138,7 +138,7 @@ fn bench_server_key_binary_function<F>(
 
         let mut rng = rand::thread_rng();
 
-        let modulus = cks.parameters.message_modulus().0 as u64;
+        let modulus = cks.parameters.message_modulus().0;
 
         let clear_0 = rng.gen::<u64>() % modulus;
         let clear_1 = rng.gen::<u64>() % modulus;
@@ -184,7 +184,7 @@ fn bench_server_key_binary_scalar_function<F>(
 
         let mut rng = rand::thread_rng();
 
-        let modulus = cks.parameters.message_modulus().0 as u64;
+        let modulus = cks.parameters.message_modulus().0;
 
         let clear_0 = rng.gen::<u64>() % modulus;
         let clear_1 = rng.gen::<u64>() % modulus;
@@ -229,7 +229,7 @@ fn bench_server_key_binary_scalar_division_function<F>(
 
         let mut rng = rand::thread_rng();
 
-        let modulus = cks.parameters.message_modulus().0 as u64;
+        let modulus = cks.parameters.message_modulus().0;
         assert_ne!(modulus, 1);
 
         let clear_0 = rng.gen::<u64>() % modulus;
@@ -270,7 +270,7 @@ fn carry_extract_bench(c: &mut Criterion, params_set: BenchParamsSet) {
 
         let mut rng = rand::thread_rng();
 
-        let modulus = cks.parameters.message_modulus().0 as u64;
+        let modulus = cks.parameters.message_modulus().0;
 
         let clear_0 = rng.gen::<u64>() % modulus;
 
@@ -306,7 +306,7 @@ fn programmable_bootstrapping_bench(c: &mut Criterion, params_set: BenchParamsSe
 
         let mut rng = rand::thread_rng();
 
-        let modulus = cks.parameters.message_modulus().0 as u64;
+        let modulus = cks.parameters.message_modulus().0;
 
         let acc = sks.generate_lookup_table(|x| x);
 

tfhe/benches/utilities.rs

@@ -196,8 +196,8 @@ pub struct CryptoParametersRecord<Scalar: UnsignedInteger> {
     pub br_base_log: Option<DecompositionBaseLog>,
     pub packing_ks_level: Option<DecompositionLevelCount>,
     pub packing_ks_base_log: Option<DecompositionBaseLog>,
-    pub message_modulus: Option<usize>,
-    pub carry_modulus: Option<usize>,
+    pub message_modulus: Option<u64>,
+    pub carry_modulus: Option<u64>,
     pub ciphertext_modulus: Option<CiphertextModulus<Scalar>>,
     pub lwe_per_glwe: Option<LweCiphertextCount>,
     pub storage_log_modulus: Option<CiphertextModulusLog>,
@@ -267,8 +267,8 @@ struct BenchmarkParametersRecord<Scalar: UnsignedInteger> {
     display_name: String,
     crypto_parameters_alias: String,
     crypto_parameters: CryptoParametersRecord<Scalar>,
-    message_modulus: Option<usize>,
-    carry_modulus: Option<usize>,
+    message_modulus: Option<u64>,
+    carry_modulus: Option<u64>,
     ciphertext_modulus: usize,
     bit_size: u32,
     polynomial_multiplication: PolynomialMultiplication,

tfhe/docs/references/fine-grained-apis/integer/README.md

@@ -104,7 +104,7 @@ fn main() {
     let msg2 = 13;
 
     // message_modulus^vec_length
-    let modulus = client_key.parameters().message_modulus().0.pow(num_block as u32) as u64;
+    let modulus = client_key.parameters().message_modulus().0.pow(num_block as u32);
 
     // We use the client key to encrypt two messages:
     let ct_1 = client_key.encrypt(msg1);

tfhe/docs/references/fine-grained-apis/integer/operations.md

@@ -116,7 +116,7 @@ fn main() {
     let scalar = 3u64;
 
     // message_modulus^vec_length
-    let modulus = client_key.parameters().message_modulus().0.pow(num_block as u32) as u64;
+    let modulus = client_key.parameters().message_modulus().0.pow(num_block as u32);
 
     // We use the client key to encrypt two messages:
     let mut ct_1 = client_key.encrypt(msg1);
@@ -154,7 +154,7 @@ fn main() {
     let scalar = 3u64;
 
     // message_modulus^vec_length
-    let modulus = client_key.parameters().message_modulus().0.pow(num_block as u32) as u64;
+    let modulus = client_key.parameters().message_modulus().0.pow(num_block as u32);
 
     // We use the client key to encrypt two messages:
     let mut ct_1 = client_key.encrypt(msg1);
@@ -193,7 +193,7 @@ fn main() {
     let scalar = 3u64;
 
     // message_modulus^vec_length
-    let modulus = client_key.parameters().message_modulus().0.pow(num_block as u32) as u64;
+    let modulus = client_key.parameters().message_modulus().0.pow(num_block as u32);
 
     // We use the client key to encrypt two messages:
     let mut ct_1 = client_key.encrypt(msg1);
@@ -240,7 +240,7 @@ fn main() {
     let scalar = 3u64;
 
     // message_modulus^vec_length
-    let modulus = client_key.parameters().message_modulus().0.pow(num_block as u32) as u64;
+    let modulus = client_key.parameters().message_modulus().0.pow(num_block as u32);
 
     // We use the client key to encrypt two messages:
     let mut ct_1 = client_key.encrypt(msg1);

tfhe/docs/references/fine-grained-apis/integer/serialization.md

@@ -31,7 +31,7 @@ fn main() -> Result<(), Box<dyn std::error::Error>> {
     let msg2 = 12;
 
     // message_modulus^vec_length
-    let modulus = client_key.parameters().message_modulus().0.pow(num_block as u32) as u64;
+    let modulus = client_key.parameters().message_modulus().0.pow(num_block as u32);
 
     let ct_1 = client_key.encrypt(msg1);
     let ct_2 = client_key.encrypt(msg2);

tfhe/docs/references/fine-grained-apis/quick_start.md

@@ -125,7 +125,7 @@ fn main() {
 
     // We use the client key to decrypt the output of the circuit:
     let output = client_key.decrypt(&ct_3);
-    assert_eq!(output, (msg1 + msg2) % modulus as u64);
+    assert_eq!(output, (msg1 + msg2) % modulus);
 }
 ```
 

tfhe/docs/references/fine-grained-apis/shortint/README.md

@@ -93,6 +93,6 @@ fn main() {
 
     // We use the client key to decrypt the output of the circuit:
     let output = client_key.decrypt(&ct_3);
-    assert_eq!(output, (msg1 + msg2) % modulus as u64);
+    assert_eq!(output, (msg1 + msg2) % modulus);
 }
 ```

tfhe/docs/references/fine-grained-apis/shortint/operations.md

@@ -71,7 +71,7 @@ fn main() {
 
     // We use the client key to decrypt the output of the circuit:
     let output = client_key.decrypt(&ct_1);
-    println!("expected {}, found {}", ((msg1 * scalar as u64 - msg2) * msg2) % modulus as u64, output);
+    println!("expected {}, found {}", ((msg1 * scalar as u64 - msg2) * msg2) % modulus, output);
 }
 ```
 
@@ -114,7 +114,7 @@ fn main() {
 
     // We use the client key to decrypt the output of the circuit:
     let output = client_key.decrypt(&ct_1);
-    assert_eq!(output, ((msg1 * scalar as u64 - msg2) * msg2) % modulus as u64);
+    assert_eq!(output, ((msg1 * scalar as u64 - msg2) * msg2) % modulus);
 }
 ```
 
@@ -146,7 +146,7 @@ fn main() {
 
     // We use the client key to decrypt the output of the circuit:
     let output = client_key.decrypt(&ct_1);
-    assert_eq!(output, ((msg1 * scalar as u64 - msg2) * msg2) % modulus as u64);
+    assert_eq!(output, ((msg1 * scalar as u64 - msg2) * msg2) % modulus);
 }
 ```
 
@@ -180,7 +180,7 @@ fn main() {
 
     // We use the client key to decrypt the output of the circuit:
     let output = client_key.decrypt(&ct_1);
-    assert_eq!(output, ((msg1 * scalar as u64 - msg2) * msg2) % modulus as u64);
+    assert_eq!(output, ((msg1 * scalar as u64 - msg2) * msg2) % modulus);
 }
 ```
 
@@ -255,7 +255,7 @@ fn main() {
 
     // We use the client key to decrypt the output of the circuit:
     let output = client_key.decrypt(&ct_3);
-    assert_eq!(output, (msg1 + msg2) % modulus as u64);
+    assert_eq!(output, (msg1 + msg2) % modulus);
 }
 ```
 
@@ -286,7 +286,7 @@ fn main() {
 
     // We use the client key to decrypt the output of the circuit:
     let output = client_key.decrypt(&ct_3);
-    assert_eq!(output, (msg1 & msg2) % modulus as u64);
+    assert_eq!(output, (msg1 & msg2) % modulus);
 }
 ```
 
@@ -317,7 +317,7 @@ fn main() {
 
     // We use the client key to decrypt the output of the circuit:
     let output = client_key.decrypt(&ct_3);
-    assert_eq!(output, (msg1 >= msg2) as u64 % modulus as u64);
+    assert_eq!(output, (msg1 >= msg2) as u64 % modulus);
 }
 ```
 
@@ -365,7 +365,7 @@ fn main() {
     let msg1 = 3;
     let msg2 = 2;
 
-    let modulus = client_key.parameters.message_modulus().0 as u64;
+    let modulus = client_key.parameters.message_modulus().0;
 
     // We use the private client key to encrypt two messages:
     let ct_1 = client_key.encrypt(msg1);

tfhe/js_on_wasm_tests/test-hlapi-signed.js

@@ -567,8 +567,8 @@ test('hlapi_compact_pk_conformance', (t) => {
     let serializedPublicKey = publicKey.safe_serialize(limit);
     let _publicKey = TfheCompactPublicKey.safe_deserialize_conformant(serializedPublicKey, limit, publicKeyParams);
 
-    const message_modulus = 4;
-    const carry_modulus = 4;
+    const message_modulus = BigInt(4);
+    const carry_modulus = BigInt(4);
     const modulus_pow_2_exponent = 64;
     const ks_level = 5;
     const ks_base_log = 3;

tfhe/src/c_api/shortint/ciphertext.rs

@@ -10,7 +10,7 @@ pub struct ShortintCompressedCiphertext(pub(in crate::c_api) shortint::Compresse
 #[no_mangle]
 pub unsafe extern "C" fn shortint_ciphertext_set_degree(
     ciphertext: *mut ShortintCiphertext,
-    degree: usize,
+    degree: u64,
 ) -> c_int {
     catch_panic(|| {
         let ciphertext = get_mut_checked(ciphertext).unwrap();
@@ -24,7 +24,7 @@ pub unsafe extern "C" fn shortint_ciphertext_set_degree(
 #[no_mangle]
 pub unsafe extern "C" fn shortint_ciphertext_get_degree(
     ciphertext: *const ShortintCiphertext,
-    result: *mut usize,
+    result: *mut u64,
 ) -> c_int {
     catch_panic(|| {
         check_ptr_is_non_null_and_aligned(result).unwrap();

tfhe/src/c_api/shortint/parameters.rs

@@ -13,7 +13,7 @@ pub enum ShortintEncryptionKeyChoice {
     ShortintEncryptionKeyChoiceSmall,
 }
 
-impl From<ShortintEncryptionKeyChoice> for crate::shortint::parameters::EncryptionKeyChoice {
+impl From<ShortintEncryptionKeyChoice> for EncryptionKeyChoice {
     fn from(value: ShortintEncryptionKeyChoice) -> Self {
         match value {
             ShortintEncryptionKeyChoice::ShortintEncryptionKeyChoiceBig => Self::Big,
@@ -34,9 +34,9 @@ pub struct ShortintPBSParameters {
     pub pbs_level: usize,
     pub ks_base_log: usize,
     pub ks_level: usize,
-    pub message_modulus: usize,
-    pub carry_modulus: usize,
-    pub max_noise_level: usize,
+    pub message_modulus: u64,
+    pub carry_modulus: u64,
+    pub max_noise_level: u64,
     pub log2_p_fail: f64,
     pub modulus_power_of_2_exponent: usize,
     pub encryption_key_choice: ShortintEncryptionKeyChoice,
@@ -56,14 +56,12 @@ impl TryFrom<ShortintPBSParameters> for crate::shortint::ClassicPBSParameters {
             pbs_level: DecompositionLevelCount(c_params.pbs_level),
             ks_base_log: DecompositionBaseLog(c_params.ks_base_log),
             ks_level: DecompositionLevelCount(c_params.ks_level),
-            message_modulus: crate::shortint::parameters::MessageModulus(c_params.message_modulus),
-            carry_modulus: crate::shortint::parameters::CarryModulus(c_params.carry_modulus),
-            ciphertext_modulus: crate::shortint::parameters::CiphertextModulus::try_new_power_of_2(
+            message_modulus: MessageModulus(c_params.message_modulus),
+            carry_modulus: CarryModulus(c_params.carry_modulus),
+            ciphertext_modulus: CiphertextModulus::try_new_power_of_2(
                 c_params.modulus_power_of_2_exponent,
             )?,
-            max_noise_level: crate::shortint::parameters::MaxNoiseLevel::new(
-                c_params.max_noise_level as u64,
-            ),
+            max_noise_level: MaxNoiseLevel::new(c_params.max_noise_level),
             log2_p_fail: c_params.log2_p_fail,
             encryption_key_choice: c_params.encryption_key_choice.into(),
         })
@@ -113,7 +111,7 @@ impl ShortintPBSParameters {
             ks_level: rust_params.ks_level.0,
             message_modulus: rust_params.message_modulus.0,
             carry_modulus: rust_params.carry_modulus.0,
-            max_noise_level: rust_params.max_noise_level.get() as usize,
+            max_noise_level: rust_params.max_noise_level.get(),
             log2_p_fail: rust_params.log2_p_fail,
             modulus_power_of_2_exponent: convert_modulus(rust_params.ciphertext_modulus),
             encryption_key_choice: ShortintEncryptionKeyChoice::convert(
@@ -170,8 +168,8 @@ impl ShortintCompactCiphertextListCastingParameters {
 pub struct ShortintCompactPublicKeyEncryptionParameters {
     pub encryption_lwe_dimension: usize,
     pub encryption_noise_distribution: crate::c_api::core_crypto::DynamicDistribution,
-    pub message_modulus: usize,
-    pub carry_modulus: usize,
+    pub message_modulus: u64,
+    pub carry_modulus: u64,
     pub modulus_power_of_2_exponent: usize,
     // Normally the CompactPublicKeyEncryptionParameters has an additional field expansion_kind,
     // but it's only used to manage different kind of parameters internally, for the C API

tfhe/src/high_level_api/integers/unsigned/tests/cpu.rs

@@ -514,7 +514,7 @@ fn test_cpk_encrypt_cast_compute_hl() {
     assert_eq!(param_pke_only.message_modulus, param_fhe.message_modulus);
     assert_eq!(param_pke_only.carry_modulus, param_fhe.carry_modulus);
 
-    let modulus = param_fhe.message_modulus.0.pow(num_block as u32) as u64;
+    let modulus = param_fhe.message_modulus.0.pow(num_block as u32);
 
     let (client_key, server_key) = generate_keys(
         ConfigBuilder::with_custom_parameters(param_fhe)
@@ -563,7 +563,7 @@ fn test_compressed_cpk_encrypt_cast_compute_hl() {
     assert_eq!(param_pke_only.message_modulus, param_fhe.message_modulus);
     assert_eq!(param_pke_only.carry_modulus, param_fhe.carry_modulus);
 
-    let modulus = param_fhe.message_modulus.0.pow(num_block as u32) as u64;
+    let modulus = param_fhe.message_modulus.0.pow(num_block as u32);
 
     let config = ConfigBuilder::with_custom_parameters(param_fhe)
         .use_dedicated_compact_public_key_parameters((param_pke_only, param_ksk))

tfhe/src/integer/ciphertext/compact_list.rs

@@ -117,7 +117,7 @@ fn sanitize_boolean_blocks(
     sks: &ServerKey,
     infos: &[DataKind],
 ) -> Vec<Ciphertext> {
-    let message_modulus = sks.message_modulus().0 as u64;
+    let message_modulus = sks.message_modulus().0;
     let msg_extract_bool = sks.key.generate_lookup_table(|x: u64| {
         let tmp = x % message_modulus;
         if tmp == 0 {
@@ -293,7 +293,7 @@ impl CompactCiphertextListBuilder {
         }
 
         // Here self.messages are decomposed blocks in range [0..message_modulus[
-        let msg_mod = self.pk.key.message_modulus().0 as u64;
+        let msg_mod = self.pk.key.message_modulus().0;
         let packed_messaged_iter = self
             .messages
             .chunks(2)
@@ -321,7 +321,7 @@ impl CompactCiphertextListBuilder {
             crs,
             metadata,
             load,
-            self.pk.key.parameters.message_modulus.0 as u64,
+            self.pk.key.parameters.message_modulus.0,
         )?;
         Ok(ProvenCompactCiphertextList {
             ct_list,
@@ -344,7 +344,7 @@ impl CompactCiphertextListBuilder {
             ));
         }
 
-        let msg_mod = self.pk.key.parameters.message_modulus.0 as u64;
+        let msg_mod = self.pk.key.parameters.message_modulus.0;
         let packed_messages = self
             .messages
             .chunks(2)
@@ -458,8 +458,8 @@ struct IntegerUnpackingToShortintCastingModeHelper {
 
 impl IntegerUnpackingToShortintCastingModeHelper {
     pub fn new(message_modulus: MessageModulus, carry_modulus: CarryModulus) -> Self {
-        let message_modulus = message_modulus.0 as u64;
-        let carry_modulus = carry_modulus.0 as u64;
+        let message_modulus = message_modulus.0;
+        let carry_modulus = carry_modulus.0;
         let msg_extract = Box::new(move |x: u64| x % message_modulus);
         let carry_extract = Box::new(move |x: u64| (x / carry_modulus) % message_modulus);
         let msg_extract_bool = Box::new(move |x: u64| {
@@ -1083,7 +1083,9 @@ mod tests {
         let metadata = [b'i', b'n', b't', b'e', b'g', b'e', b'r'];
 
         let num_blocks = 4usize;
-        let modulus = (pke_params.message_modulus.0 as u64)
+        let modulus = pke_params
+            .message_modulus
+            .0
             .checked_pow(num_blocks as u32)
             .unwrap();