# 'FHE' Dialect High Level Fully Homomorphic Encryption dialect A dialect for representation of high level operation on fully homomorphic ciphertext. ## Operation definition ### `FHE.add_eint_int` (::mlir::concretelang::FHE::AddEintIntOp) Adds an encrypted integer and a clear integer The clear integer must have at most one more bit than the encrypted integer and the result must have the same width and the same signedness as the encrypted integer. Example: ```mlir // ok "FHE.add_eint_int"(%a, %i) : (!FHE.eint<2>, i3) -> !FHE.eint<2> "FHE.add_eint_int"(%a, %i) : (!FHE.esint<2>, i3) -> !FHE.esint<2> // error "FHE.add_eint_int"(%a, %i) : (!FHE.eint<2>, i4) -> !FHE.eint<2> "FHE.add_eint_int"(%a, %i) : (!FHE.eint<2>, i3) -> !FHE.eint<3> "FHE.add_eint_int"(%a, %i) : (!FHE.eint<2>, i3) -> !FHE.esint<2> ``` Traits: AlwaysSpeculatableImplTrait Interfaces: Binary, BinaryEintInt, ConditionallySpeculatable, MaxNoise, NoMemoryEffect (MemoryEffectOpInterface) Effects: MemoryEffects::Effect{} #### Operands: | Operand | Description | | :-----: | ----------- | | `a` | | `b` | integer #### Results: | Result | Description | | :----: | ----------- | «unnamed» | ### `FHE.add_eint` (::mlir::concretelang::FHE::AddEintOp) Adds two encrypted integers The encrypted integers and the result must have the same width and the same signedness. Example: ```mlir // ok "FHE.add_eint"(%a, %b): (!FHE.eint<2>, !FHE.eint<2>) -> (!FHE.eint<2>) "FHE.add_eint"(%a, %b): (!FHE.esint<2>, !FHE.esint<2>) -> (!FHE.esint<2>) // error "FHE.add_eint"(%a, %b): (!FHE.eint<2>, !FHE.eint<3>) -> (!FHE.eint<2>) "FHE.add_eint"(%a, %b): (!FHE.eint<2>, !FHE.eint<2>) -> (!FHE.eint<3>) "FHE.add_eint"(%a, %b): (!FHE.eint<2>, !FHE.eint<2>) -> (!FHE.esint<2>) "FHE.add_eint"(%a, %b): (!FHE.esint<2>, !FHE.eint<2>) -> (!FHE.eint<2>) ``` Traits: AlwaysSpeculatableImplTrait Interfaces: AdditiveNoise, BinaryEint, ConditionallySpeculatable, NoMemoryEffect (MemoryEffectOpInterface) Effects: MemoryEffects::Effect{} #### Operands: | Operand | Description | | :-----: | ----------- | | `a` | | `b` | #### Results: | Result | Description | | :----: | ----------- | «unnamed» | ### `FHE.apply_lookup_table` (::mlir::concretelang::FHE::ApplyLookupTableEintOp) Applies a clear lookup table to an encrypted integer The width of the result can be different than the width of the operand. The lookup table must be a tensor of size `2^p` where `p` is the width of the encrypted integer. Example: ```mlir // ok "FHE.apply_lookup_table"(%a, %lut): (!FHE.eint<2>, tensor<4xi64>) -> (!FHE.eint<2>) "FHE.apply_lookup_table"(%a, %lut): (!FHE.eint<2>, tensor<4xi64>) -> (!FHE.eint<3>) "FHE.apply_lookup_table"(%a, %lut): (!FHE.eint<3>, tensor<4xi64>) -> (!FHE.eint<2>) // error "FHE.apply_lookup_table"(%a, %lut): (!FHE.eint<2>, tensor<8xi64>) -> (!FHE.eint<2>) ``` Traits: AlwaysSpeculatableImplTrait Interfaces: ConditionallySpeculatable, ConstantNoise, NoMemoryEffect (MemoryEffectOpInterface) Effects: MemoryEffects::Effect{} #### Operands: | Operand | Description | | :-----: | ----------- | | `a` | | `lut` | tensor of integer values #### Results: | Result | Description | | :----: | ----------- | «unnamed» | ### `FHE.and` (::mlir::concretelang::FHE::BoolAndOp) Applies an AND gate to two encrypted boolean values Example: ```mlir "FHE.and"(%a, %b): (!FHE.ebool, !FHE.ebool) -> (!FHE.ebool) ``` Traits: AlwaysSpeculatableImplTrait Interfaces: ConditionallySpeculatable, NoMemoryEffect (MemoryEffectOpInterface) Effects: MemoryEffects::Effect{} #### Operands: | Operand | Description | | :-----: | ----------- | | `left` | An encrypted boolean | `right` | An encrypted boolean #### Results: | Result | Description | | :----: | ----------- | «unnamed» | An encrypted boolean ### `FHE.nand` (::mlir::concretelang::FHE::BoolNandOp) Applies a NAND gate to two encrypted boolean values Example: ```mlir "FHE.nand"(%a, %b): (!FHE.ebool, !FHE.ebool) -> (!FHE.ebool) ``` Traits: AlwaysSpeculatableImplTrait Interfaces: ConditionallySpeculatable, NoMemoryEffect (MemoryEffectOpInterface) Effects: MemoryEffects::Effect{} #### Operands: | Operand | Description | | :-----: | ----------- | | `left` | An encrypted boolean | `right` | An encrypted boolean #### Results: | Result | Description | | :----: | ----------- | «unnamed» | An encrypted boolean ### `FHE.not` (::mlir::concretelang::FHE::BoolNotOp) Applies a NOT gate to an encrypted boolean value Example: ```mlir "FHE.not"(%a): (!FHE.ebool) -> (!FHE.ebool) ``` Traits: AlwaysSpeculatableImplTrait Interfaces: ConditionallySpeculatable, NoMemoryEffect (MemoryEffectOpInterface), UnaryEint Effects: MemoryEffects::Effect{} #### Operands: | Operand | Description | | :-----: | ----------- | | `value` | An encrypted boolean #### Results: | Result | Description | | :----: | ----------- | «unnamed» | An encrypted boolean ### `FHE.or` (::mlir::concretelang::FHE::BoolOrOp) Applies an OR gate to two encrypted boolean values Example: ```mlir "FHE.or"(%a, %b): (!FHE.ebool, !FHE.ebool) -> (!FHE.ebool) ``` Traits: AlwaysSpeculatableImplTrait Interfaces: ConditionallySpeculatable, NoMemoryEffect (MemoryEffectOpInterface) Effects: MemoryEffects::Effect{} #### Operands: | Operand | Description | | :-----: | ----------- | | `left` | An encrypted boolean | `right` | An encrypted boolean #### Results: | Result | Description | | :----: | ----------- | «unnamed» | An encrypted boolean ### `FHE.xor` (::mlir::concretelang::FHE::BoolXorOp) Applies an XOR gate to two encrypted boolean values Example: ```mlir "FHE.xor"(%a, %b): (!FHE.ebool, !FHE.ebool) -> (!FHE.ebool) ``` Traits: AlwaysSpeculatableImplTrait Interfaces: ConditionallySpeculatable, NoMemoryEffect (MemoryEffectOpInterface) Effects: MemoryEffects::Effect{} #### Operands: | Operand | Description | | :-----: | ----------- | | `left` | An encrypted boolean | `right` | An encrypted boolean #### Results: | Result | Description | | :----: | ----------- | «unnamed» | An encrypted boolean ### `FHE.change_partition` (::mlir::concretelang::FHE::ChangePartitionEintOp) Change partition if necessary. Changing the partition of a ciphertext. If necessary, it keyswitch the ciphertext to a different key having a different set of parameters than the original one. Example: ```mlir %from_src = "FHE.change_partition"(%eint) {src = #FHE.partition} : (!FHE.eint<16>) -> (!FHE.eint<16>) %to_dest = "FHE.change_partition"(%eint) {dest = #FHE.partition} : (!FHE.eint<16>) -> (!FHE.eint<16>) ``` Traits: AlwaysSpeculatableImplTrait Interfaces: ConditionallySpeculatable, NoMemoryEffect (MemoryEffectOpInterface), UnaryEint Effects: MemoryEffects::Effect{} #### Attributes: | Attribute | MLIR Type | Description | | :-------: | :-------: | ----------- | | `src` | ::mlir::concretelang::FHE::PartitionAttr | An attribute representing a partition. | `dest` | ::mlir::concretelang::FHE::PartitionAttr | An attribute representing a partition. #### Operands: | Operand | Description | | :-----: | ----------- | | `input` | #### Results: | Result | Description | | :----: | ----------- | «unnamed» | ### `FHE.from_bool` (::mlir::concretelang::FHE::FromBoolOp) Cast a boolean to an unsigned integer Examples: ```mlir "FHE.from_bool"(%x) : (!FHE.ebool) -> !FHE.eint<1> "FHE.from_bool"(%x) : (!FHE.ebool) -> !FHE.eint<2> "FHE.from_bool"(%x) : (!FHE.ebool) -> !FHE.eint<4> ``` Traits: AlwaysSpeculatableImplTrait Interfaces: ConditionallySpeculatable, NoMemoryEffect (MemoryEffectOpInterface), UnaryEint Effects: MemoryEffects::Effect{} #### Operands: | Operand | Description | | :-----: | ----------- | | `input` | An encrypted boolean #### Results: | Result | Description | | :----: | ----------- | «unnamed» | An encrypted unsigned integer ### `FHE.gen_gate` (::mlir::concretelang::FHE::GenGateOp) Applies a truth table based on two boolean inputs Truth table must be a tensor of four boolean values. Example: ```mlir // ok "FHE.gen_gate"(%a, %b, %ttable): (!FHE.ebool, !FHE.ebool, tensor<4xi64>) -> (!FHE.ebool) // error "FHE.gen_gate"(%a, %b, %ttable): (!FHE.ebool, !FHE.ebool, tensor<7xi64>) -> (!FHE.ebool) ``` Traits: AlwaysSpeculatableImplTrait Interfaces: ConditionallySpeculatable, NoMemoryEffect (MemoryEffectOpInterface) Effects: MemoryEffects::Effect{} #### Operands: | Operand | Description | | :-----: | ----------- | | `left` | An encrypted boolean | `right` | An encrypted boolean | `truth_table` | tensor of integer values #### Results: | Result | Description | | :----: | ----------- | «unnamed» | An encrypted boolean ### `FHE.lsb` (::mlir::concretelang::FHE::LsbEintOp) Extract the lowest significant bit at a given precision. This operation extracts the lsb of a ciphertext in a specific precision. Extracting the lsb with the smallest precision: ```mlir // Checking if even or odd %even = "FHE.lsb"(%a): (!FHE.eint<4>) -> (!FHE.eint<1>) Usually when you extract the lsb bit, you also need to extract the next one. In that case you first need to clear the first lsb of the input to be able to reduce its precision and extract the next one. To be able to clear the lsb just extracted, you can get it in the original precision. Example: ```mlir // Extracting the first lsb with original precision %lsb_0 = "FHE.lsb"(%input): (!FHE.eint<4>) -> (!FHE.eint<4>) // Clearing the first lsb from original input %input_lsb0_cleared = "FHE.sub_eint"(%input, %lsb_0) : (!FHE.eint<4>, !FHE.eint<4>) -> (!FHE.eint<4>) // Reducing the precision of the input %input_3b = "FHE.reinterpret_precision(%input) : (!FHE.eint<4>) -> !FHE.eint<3> // Now, we can do it again with the second lsb %lsb_1 = "FHE.lsb"(%input_3b): (!FHE.eint<3>) -> (!FHE.eint<3>) ... // later if you need %b_lsb at same position as in the input %lsb_1_at_input_position = "FHE.reinterpret_precision(%b_lsb)" : (!FHE.eint<3>) -> !FHE.eint<4> // that way you can recombine the extracted bits %input_mod_4 = "FHE.add_eint"(%lsb_0, %lsb_1_at_input_position) : (!FHE.eint<4>, !FHE.eint<4>) -> (!FHE.eint<4>) ``` Traits: AlwaysSpeculatableImplTrait Interfaces: ConditionallySpeculatable, ConstantNoise, NoMemoryEffect (MemoryEffectOpInterface), UnaryEint Effects: MemoryEffects::Effect{} #### Operands: | Operand | Description | | :-----: | ----------- | | `input` | #### Results: | Result | Description | | :----: | ----------- | «unnamed» | ### `FHE.max_eint` (::mlir::concretelang::FHE::MaxEintOp) Retrieve the maximum of two encrypted integers. Retrieve the maximum of two encrypted integers using the formula, 'max(x, y) == max(x - y, 0) + y'. The input and output types should be the same. If `x - y`` inside the max overflows or underflows, the behavior is undefined. To support the full range, you should increase the bit-width by 1 manually. Example: ```mlir // ok "FHE.max_eint"(%x, %y) : (!FHE.eint<2>, !FHE.eint<2>) -> !FHE.eint<2> "FHE.max_eint"(%x, %y) : (!FHE.esint<3>, !FHE.esint<3>) -> !FHE.esint<3> // error "FHE.max_eint"(%x, %y) : (!FHE.eint<2>, !FHE.eint<3>) -> !FHE.eint<2> "FHE.max_eint"(%x, %y) : (!FHE.eint<2>, !FHE.eint<2>) -> !FHE.esint<2> "FHE.max_eint"(%x, %y) : (!FHE.esint<2>, !FHE.eint<2>) -> !FHE.eint<2> ``` Traits: AlwaysSpeculatableImplTrait Interfaces: BinaryEint, ConditionallySpeculatable, NoMemoryEffect (MemoryEffectOpInterface) Effects: MemoryEffects::Effect{} #### Operands: | Operand | Description | | :-----: | ----------- | | `x` | | `y` | #### Results: | Result | Description | | :----: | ----------- | «unnamed» | ### `FHE.mul_eint_int` (::mlir::concretelang::FHE::MulEintIntOp) Multiply an encrypted integer with a clear integer The clear integer must have one more bit than the encrypted integer and the result must have the same width and the same signedness as the encrypted integer. Example: ```mlir // ok "FHE.mul_eint_int"(%a, %i) : (!FHE.eint<2>, i3) -> !FHE.eint<2> "FHE.mul_eint_int"(%a, %i) : (!FHE.esint<2>, i3) -> !FHE.esint<2> // error "FHE.mul_eint_int"(%a, %i) : (!FHE.eint<2>, i4) -> !FHE.eint<2> "FHE.mul_eint_int"(%a, %i) : (!FHE.eint<2>, i3) -> !FHE.eint<3> "FHE.mul_eint_int"(%a, %i) : (!FHE.eint<2>, i3) -> !FHE.esint<2> ``` Traits: AlwaysSpeculatableImplTrait Interfaces: Binary, BinaryEintInt, ConditionallySpeculatable, NoMemoryEffect (MemoryEffectOpInterface) Effects: MemoryEffects::Effect{} #### Operands: | Operand | Description | | :-----: | ----------- | | `a` | | `b` | integer #### Results: | Result | Description | | :----: | ----------- | «unnamed» | ### `FHE.mul_eint` (::mlir::concretelang::FHE::MulEintOp) Multiplies two encrypted integers The encrypted integers and the result must have the same width and signedness. Also, due to the current implementation, one supplementary bit of width must be provided, in addition to the number of bits needed to encode the largest output value. Example: ```mlir // ok "FHE.mul_eint"(%a, %b): (!FHE.eint<2>, !FHE.eint<2>) -> (!FHE.eint<2>) "FHE.mul_eint"(%a, %b): (!FHE.eint<3>, !FHE.eint<3>) -> (!FHE.eint<3>) "FHE.mul_eint"(%a, %b): (!FHE.esint<3>, !FHE.esint<3>) -> (!FHE.esint<3>) // error "FHE.mul_eint"(%a, %b): (!FHE.eint<2>, !FHE.eint<3>) -> (!FHE.eint<2>) "FHE.mul_eint"(%a, %b): (!FHE.eint<2>, !FHE.eint<2>) -> (!FHE.eint<3>) "FHE.mul_eint"(%a, %b): (!FHE.eint<2>, !FHE.eint<2>) -> (!FHE.esint<2>) "FHE.mul_eint"(%a, %b): (!FHE.esint<2>, !FHE.eint<2>) -> (!FHE.eint<2>) ``` Traits: AlwaysSpeculatableImplTrait Interfaces: BinaryEint, ConditionallySpeculatable, NoMemoryEffect (MemoryEffectOpInterface) Effects: MemoryEffects::Effect{} #### Operands: | Operand | Description | | :-----: | ----------- | | `rhs` | | `lhs` | #### Results: | Result | Description | | :----: | ----------- | «unnamed» | ### `FHE.mux` (::mlir::concretelang::FHE::MuxOp) Multiplexer for two encrypted boolean inputs, based on an encrypted condition Example: ```mlir "FHE.mux"(%cond, %c1, %c2): (!FHE.ebool, !FHE.ebool, !FHE.ebool) -> (!FHE.ebool) ``` Traits: AlwaysSpeculatableImplTrait Interfaces: ConditionallySpeculatable, NoMemoryEffect (MemoryEffectOpInterface) Effects: MemoryEffects::Effect{} #### Operands: | Operand | Description | | :-----: | ----------- | | `cond` | An encrypted boolean | `c1` | An encrypted boolean | `c2` | An encrypted boolean #### Results: | Result | Description | | :----: | ----------- | «unnamed» | An encrypted boolean ### `FHE.neg_eint` (::mlir::concretelang::FHE::NegEintOp) Negates an encrypted integer The result must have the same width and the same signedness as the encrypted integer. Example: ```mlir // ok "FHE.neg_eint"(%a): (!FHE.eint<2>) -> (!FHE.eint<2>) "FHE.neg_eint"(%a): (!FHE.esint<2>) -> (!FHE.esint<2>) // error "FHE.neg_eint"(%a): (!FHE.eint<2>) -> (!FHE.eint<3>) "FHE.neg_eint"(%a): (!FHE.eint<2>) -> (!FHE.esint<2>) ``` Traits: AlwaysSpeculatableImplTrait Interfaces: ConditionallySpeculatable, MaxNoise, NoMemoryEffect (MemoryEffectOpInterface), UnaryEint Effects: MemoryEffects::Effect{} #### Operands: | Operand | Description | | :-----: | ----------- | | `a` | #### Results: | Result | Description | | :----: | ----------- | «unnamed» | ### `FHE.reinterpret_precision` (::mlir::concretelang::FHE::ReinterpretPrecisionEintOp) Reinterpret the ciphertext with a different precision. Changing the precision of a ciphertext. It changes both the precision, the value, and in certain cases the correctness of the ciphertext. Changing to - a bigger precision is always safe. This is equivalent to a shift left for the value. - a smaller precision is only safe if you clear the lowest bits that are discarded. If not, you can assume small errors on the next TLU. This is equivalent to a shift right for the value. Example: ```mlir // assuming %a is stored as 4bits but can be stored with only 2bits // we can reduce its storage precision %shifted_a = "FHE.mul_eint_int"(%a, %c_4): (!FHE.eint<4>) -> (!FHE.eint<4>) %a_small_precision = "FHE.reinterpret_precision"(%shifted_a, %lsb) : (!FHE.eint<4>) -> (!FHE.eint<2>) ``` Traits: AlwaysSpeculatableImplTrait Interfaces: ConditionallySpeculatable, NoMemoryEffect (MemoryEffectOpInterface), UnaryEint Effects: MemoryEffects::Effect{} #### Operands: | Operand | Description | | :-----: | ----------- | | `input` | #### Results: | Result | Description | | :----: | ----------- | «unnamed» | ### `FHE.round` (::mlir::concretelang::FHE::RoundEintOp) Rounds a ciphertext to a smaller precision. Assuming a ciphertext whose message is implemented over `p` bits, this operation rounds it to fit to `q` bits with `p>q`. Example: ```mlir // ok "FHE.round"(%a): (!FHE.eint<6>) -> (!FHE.eint<5>) "FHE.round"(%a): (!FHE.eint<5>) -> (!FHE.eint<3>) "FHE.round"(%a): (!FHE.eint<3>) -> (!FHE.eint<2>) "FHE.round"(%a): (!FHE.esint<3>) -> (!FHE.esint<2>) // error "FHE.round"(%a): (!FHE.eint<6>) -> (!FHE.eint<6>) "FHE.round"(%a): (!FHE.eint<4>) -> (!FHE.eint<5>) "FHE.round"(%a): (!FHE.eint<4>) -> (!FHE.esint<5>) ``` Traits: AlwaysSpeculatableImplTrait Interfaces: ConditionallySpeculatable, NoMemoryEffect (MemoryEffectOpInterface), UnaryEint Effects: MemoryEffects::Effect{} #### Operands: | Operand | Description | | :-----: | ----------- | | `input` | #### Results: | Result | Description | | :----: | ----------- | «unnamed» | ### `FHE.sub_eint_int` (::mlir::concretelang::FHE::SubEintIntOp) Subtract a clear integer from an encrypted integer The clear integer must have one more bit than the encrypted integer and the result must have the same width and the same signedness as the encrypted integer. Example: ```mlir // ok "FHE.sub_eint_int"(%i, %a) : (!FHE.eint<2>, i3) -> !FHE.eint<2> "FHE.sub_eint_int"(%i, %a) : (!FHE.esint<2>, i3) -> !FHE.esint<2> // error "FHE.sub_eint_int"(%i, %a) : (!FHE.eint<2>, i4) -> !FHE.eint<2> "FHE.sub_eint_int"(%i, %a) : (!FHE.eint<2>, i3) -> !FHE.eint<3> "FHE.sub_eint_int"(%i, %a) : (!FHE.eint<2>, i3) -> !FHE.esint<2> ``` Traits: AlwaysSpeculatableImplTrait Interfaces: Binary, BinaryEintInt, ConditionallySpeculatable, MaxNoise, NoMemoryEffect (MemoryEffectOpInterface) Effects: MemoryEffects::Effect{} #### Operands: | Operand | Description | | :-----: | ----------- | | `a` | | `b` | integer #### Results: | Result | Description | | :----: | ----------- | «unnamed» | ### `FHE.sub_eint` (::mlir::concretelang::FHE::SubEintOp) Subtract an encrypted integer from an encrypted integer The encrypted integers and the result must have the same width and the same signedness. Example: ```mlir // ok "FHE.sub_eint"(%a, %b): (!FHE.eint<2>, !FHE.eint<2>) -> (!FHE.eint<2>) "FHE.sub_eint"(%a, %b): (!FHE.esint<2>, !FHE.esint<2>) -> (!FHE.esint<2>) // error "FHE.sub_eint"(%a, %b): (!FHE.eint<2>, !FHE.eint<3>) -> (!FHE.eint<2>) "FHE.sub_eint"(%a, %b): (!FHE.eint<2>, !FHE.eint<2>) -> (!FHE.eint<3>) "FHE.sub_eint"(%a, %b): (!FHE.eint<2>, !FHE.esint<2>) -> (!FHE.esint<2>) "FHE.sub_eint"(%a, %b): (!FHE.eint<2>, !FHE.eint<2>) -> (!FHE.esint<2>) ``` Traits: AlwaysSpeculatableImplTrait Interfaces: AdditiveNoise, BinaryEint, ConditionallySpeculatable, NoMemoryEffect (MemoryEffectOpInterface) Effects: MemoryEffects::Effect{} #### Operands: | Operand | Description | | :-----: | ----------- | | `a` | | `b` | #### Results: | Result | Description | | :----: | ----------- | «unnamed» | ### `FHE.sub_int_eint` (::mlir::concretelang::FHE::SubIntEintOp) Subtract an encrypted integer from a clear integer The clear integer must have one more bit than the encrypted integer and the result must have the same width and the same signedness as the encrypted integer. Example: ```mlir // ok "FHE.sub_int_eint"(%i, %a) : (i3, !FHE.eint<2>) -> !FHE.eint<2> "FHE.sub_int_eint"(%i, %a) : (i3, !FHE.esint<2>) -> !FHE.esint<2> // error "FHE.sub_int_eint"(%i, %a) : (i4, !FHE.eint<2>) -> !FHE.eint<2> "FHE.sub_int_eint"(%i, %a) : (i3, !FHE.eint<2>) -> !FHE.eint<3> "FHE.sub_int_eint"(%i, %a) : (i3, !FHE.eint<2>) -> !FHE.esint<2> ``` Traits: AlwaysSpeculatableImplTrait Interfaces: Binary, BinaryIntEint, ConditionallySpeculatable, MaxNoise, NoMemoryEffect (MemoryEffectOpInterface) Effects: MemoryEffects::Effect{} #### Operands: | Operand | Description | | :-----: | ----------- | | `a` | integer | `b` | #### Results: | Result | Description | | :----: | ----------- | «unnamed» | ### `FHE.to_bool` (::mlir::concretelang::FHE::ToBoolOp) Cast an unsigned integer to a boolean The input must be of width one or two. Two being the current representation of an encrypted boolean, leaving one bit for the carry. Examples: ```mlir // ok "FHE.to_bool"(%x) : (!FHE.eint<1>) -> !FHE.ebool "FHE.to_bool"(%x) : (!FHE.eint<2>) -> !FHE.ebool // error "FHE.to_bool"(%x) : (!FHE.eint<3>) -> !FHE.ebool ``` Traits: AlwaysSpeculatableImplTrait Interfaces: ConditionallySpeculatable, NoMemoryEffect (MemoryEffectOpInterface), UnaryEint Effects: MemoryEffects::Effect{} #### Operands: | Operand | Description | | :-----: | ----------- | | `input` | An encrypted unsigned integer #### Results: | Result | Description | | :----: | ----------- | «unnamed» | An encrypted boolean ### `FHE.to_signed` (::mlir::concretelang::FHE::ToSignedOp) Cast an unsigned integer to a signed one The result must have the same width as the input. The behavior is undefined on overflow/underflow. Examples: ```mlir // ok "FHE.to_signed"(%x) : (!FHE.eint<2>) -> !FHE.esint<2> // error "FHE.to_signed"(%x) : (!FHE.eint<2>) -> !FHE.esint<3> ``` Traits: AlwaysSpeculatableImplTrait Interfaces: ConditionallySpeculatable, NoMemoryEffect (MemoryEffectOpInterface), UnaryEint Effects: MemoryEffects::Effect{} #### Operands: | Operand | Description | | :-----: | ----------- | | `input` | An encrypted unsigned integer #### Results: | Result | Description | | :----: | ----------- | «unnamed» | An encrypted signed integer ### `FHE.to_unsigned` (::mlir::concretelang::FHE::ToUnsignedOp) Cast a signed integer to an unsigned one The result must have the same width as the input. The behavior is undefined on overflow/underflow. Examples: ```mlir // ok "FHE.to_unsigned"(%x) : (!FHE.esint<2>) -> !FHE.eint<2> // error "FHE.to_unsigned"(%x) : (!FHE.esint<2>) -> !FHE.eint<3> ``` Traits: AlwaysSpeculatableImplTrait Interfaces: ConditionallySpeculatable, NoMemoryEffect (MemoryEffectOpInterface), UnaryEint Effects: MemoryEffects::Effect{} #### Operands: | Operand | Description | | :-----: | ----------- | | `input` | An encrypted signed integer #### Results: | Result | Description | | :----: | ----------- | «unnamed» | An encrypted unsigned integer ### `FHE.zero` (::mlir::concretelang::FHE::ZeroEintOp) Returns a trivial encrypted integer of 0 Example: ```mlir "FHE.zero"() : () -> !FHE.eint<2> "FHE.zero"() : () -> !FHE.esint<2> ``` Traits: AlwaysSpeculatableImplTrait Interfaces: ConditionallySpeculatable, NoMemoryEffect (MemoryEffectOpInterface), ZeroNoise Effects: MemoryEffects::Effect{} #### Results: | Result | Description | | :----: | ----------- | | `out` | ### `FHE.zero_tensor` (::mlir::concretelang::FHE::ZeroTensorOp) Creates a new tensor with all elements initialized to an encrypted zero. Creates a new tensor with the shape specified in the result type and initializes its elements with an encrypted zero. Example: ```mlir %tensor = "FHE.zero_tensor"() : () -> tensor<5x!FHE.eint<4>> %tensor = "FHE.zero_tensor"() : () -> tensor<5x!FHE.esint<4>> ``` Traits: AlwaysSpeculatableImplTrait Interfaces: ConditionallySpeculatable, NoMemoryEffect (MemoryEffectOpInterface), ZeroNoise Effects: MemoryEffects::Effect{} #### Results: | Result | Description | | :----: | ----------- | | `tensor` | ## Attribute definition ### PartitionAttr An attribute representing a partition. Syntax: ``` #FHE.partition< StringAttr, # name uint64_t, # lweDim uint64_t, # glweDim uint64_t, # polySize uint64_t, # pbsBaseLog uint64_t # pbsLevel > ``` #### Parameters: | Parameter | C++ type | Description | | :-------: | :-------: | ----------- | | name | `StringAttr` | | | lweDim | `uint64_t` | | | glweDim | `uint64_t` | | | polySize | `uint64_t` | | | pbsBaseLog | `uint64_t` | | | pbsLevel | `uint64_t` | | ## Type definition ### EncryptedBooleanType An encrypted boolean Syntax: `!FHE.ebool` An encrypted boolean. ### EncryptedSignedIntegerType An encrypted signed integer An encrypted signed integer with `width` bits to performs FHE Operations. Examples: ```mlir !FHE.esint<7> !FHE.esint<6> ``` #### Parameters: | Parameter | C++ type | Description | | :-------: | :-------: | ----------- | | width | `unsigned` | | ### EncryptedUnsignedIntegerType An encrypted unsigned integer An encrypted unsigned integer with `width` bits to performs FHE Operations. Examples: ```mlir !FHE.eint<7> !FHE.eint<6> ``` #### Parameters: | Parameter | C++ type | Description | | :-------: | :-------: | ----------- | | width | `unsigned` | |