New Kernel Generators for CKKS

kerngen/pisa_generators/basic.py

@@ -296,3 +296,26 @@ def extract_last_part_polys(input0: Polys, rns: int) -> Tuple[Polys, Polys, Poly
     upto_last_coeffs.start_parts = 0
 
     return input_last_part, last_coeff, upto_last_coeffs
+
+
+def split_last_rns_polys(input0: Polys) -> Tuple[Polys, Polys]:
+    """Split and extract last RNS of input0"""
+    return Polys.from_polys(input0, mode="last_rns"), Polys.from_polys(
+        input0, mode="drop_last_rns"
+    )
+
+
+def duplicate_polys(input0: Polys, name: str) -> Polys:
+    """Creates a duplicate of input0 with new name"""
+    return Polys(name, input0.parts, input0.rns, input0.start_parts, input0.start_rns)
+
+
+def common_immediates(
+    r2_rns=None, iq_rns=None
+) -> Tuple[Immediate, Immediate, Immediate]:
+    """Generate commonly used immediates"""
+    return (
+        Immediate(name="one"),
+        Immediate(name="R2", rns=r2_rns),
+        Immediate(name="iq", rns=iq_rns),
+    )

kerngen/pisa_generators/manifest.json

@@ -14,5 +14,16 @@
     "ROTATE": ["Rotate", "rotate.py"]
   },
   "CKKS": {
+    "ADD": ["Add", "basic.py"],
+    "MUL": ["Mul", "basic.py"],
+    "MULI": ["Muli", "basic.py"],
+    "COPY": ["Copy", "basic.py"],
+    "SUB": ["Sub", "basic.py"],
+    "SQUARE": ["Square", "square.py"],
+    "NTT": ["NTT", "ntt.py"],
+    "INTT": ["INTT", "ntt.py"],
+    "MOD": ["Mod", "mod.py"],
+    "MODUP": ["Modup", "mod.py"],
+    "RESCALE": ["Rescale", "rescale.py"]
   }
 }

kerngen/pisa_generators/mod.py

@@ -1,15 +1,25 @@
+# Copyright (C) 2024 Intel Corporation
+# SPDX-License-Identifier: Apache-2.0
+
 # Copyright (C) 2024 Intel Corporation
 
 """Module containing conversions or operations from isa to p-isa."""
 
 from dataclasses import dataclass
-from itertools import product
 
-from high_parser.pisa_operations import PIsaOp, Comment, Muli as pisa_op_muli
+from high_parser.pisa_operations import PIsaOp, Comment
 from high_parser import KernelContext, Immediate, HighOp, Polys
 
-from .basic import Add, Muli, mixed_to_pisa_ops
+from .basic import (
+    Add,
+    Muli,
+    mixed_to_pisa_ops,
+    split_last_rns_polys,
+    duplicate_polys,
+    common_immediates,
+)
 from .ntt import INTT, NTT
+from .partial_op import muli_last_half
 
 
 @dataclass
@@ -22,27 +32,18 @@ class Mod(HighOp):
 
     def to_pisa(self) -> list[PIsaOp]:
         """Return the p-isa code to perform an mod switch down"""
-        # Convenience and Immediates
-        context = self.context
+        # Immediates
         last_q = self.input0.rns - 1
         it = Immediate(name="it")
-        one = Immediate(name="one")
-        r2 = Immediate(name="R2", rns=last_q)
-        iq = Immediate(name="iq", rns=last_q)
         t = Immediate(name="t", rns=last_q)
+        one, r2, iq = common_immediates(r2_rns=last_q, iq_rns=last_q)
 
         # Drop down input rns
-        input_last_rns = Polys.from_polys(self.input0, mode="last_rns")
-        input_remaining_rns = Polys.from_polys(self.input0, mode="drop_last_rns")
+        input_last_rns, input_remaining_rns = split_last_rns_polys(self.input0)
 
         # Temp.
-        y = Polys(
-            "y",
-            input_last_rns.parts,
-            input_last_rns.rns,
-            start_rns=input_last_rns.start_rns,
-        )
-        x = Polys("x", input_remaining_rns.parts, input_remaining_rns.rns)
+        temp_input_last_rns = duplicate_polys(input_last_rns, "y")
+        temp_input_remaining_rns = duplicate_polys(input_remaining_rns, "x")
 
         # Compute the `delta_i = t * [-t^-1 * c_i] mod ql` where `i` are the parts
         # The `one` acts as a select flag as whether or not R2 the Montgomery
@@ -51,30 +52,31 @@ def to_pisa(self) -> list[PIsaOp]:
             [
                 Comment("Start of mod kernel"),
                 Comment("Compute the delta from last rns"),
-                INTT(context, y, input_last_rns),
-                Muli(context, y, y, it),
-                Muli(context, y, y, one),
+                INTT(self.context, temp_input_last_rns, input_last_rns),
+                Muli(self.context, temp_input_last_rns, temp_input_last_rns, it),
+                Muli(self.context, temp_input_last_rns, temp_input_last_rns, one),
                 Comment("Compute the remaining rns"),
                 # drop down to pisa ops to use correct rns q
-                [
-                    pisa_op_muli(
-                        self.context.label,
-                        x(part, q, unit),
-                        y(part, last_q, unit),
-                        r2(part, q, unit),
-                        q,
-                    )
-                    for part, q, unit in product(
-                        range(input_remaining_rns.parts),
-                        range(input_remaining_rns.rns),
-                        range(context.units),
-                    )
-                ],
-                NTT(context, x, x),
-                Muli(context, x, x, t),
+                muli_last_half(
+                    self.context,
+                    temp_input_remaining_rns,
+                    temp_input_last_rns,
+                    r2,
+                    input_remaining_rns,
+                    last_q,
+                ),
+                NTT(self.context, temp_input_remaining_rns, temp_input_remaining_rns),
+                Muli(
+                    self.context, temp_input_remaining_rns, temp_input_remaining_rns, t
+                ),
                 Comment("Add the delta correction to mod down polys"),
-                Add(context, x, x, input_remaining_rns),
-                Muli(context, self.output, x, iq),
+                Add(
+                    self.context,
+                    temp_input_remaining_rns,
+                    temp_input_remaining_rns,
+                    input_remaining_rns,
+                ),
+                Muli(self.context, self.output, temp_input_remaining_rns, iq),
                 Comment("End of mod kernel"),
             ]
         )

kerngen/pisa_generators/partial_op.py

@@ -0,0 +1,124 @@
+# Copyright (C) 2024 Intel Corporation
+# SPDX-License-Identifier: Apache-2.0
+
+"""Module containing helper methods to support binary operations using partial polys (last RNS and/or last part)"""
+from dataclasses import dataclass
+from itertools import product
+
+from high_parser import KernelContext, Polys
+
+from high_parser.pisa_operations import Sub as pisa_op_sub
+from high_parser.pisa_operations import Add as pisa_op_add
+from high_parser.pisa_operations import Muli as pisa_op_muli
+
+# pylint: disable=too-many-arguments
+# pylint: disable=too-many-positional-arguments
+
+
+@dataclass
+class PartialOpOptions:
+    """Optional arguments for partial_op helper function"""
+
+    output_last_q: bool = False
+    input0_last_q: bool = False
+    input1_last_q: bool = False
+    input1_first_part: bool = False
+    op_last_q: bool = False
+
+
+@dataclass
+class PartialOpPolys:
+    """Polynomials used in partial ops"""
+
+    output: Polys
+    input0: Polys
+    input1: Polys
+    input_remaining_rns: Polys
+
+
+def partial_op(
+    context: KernelContext,
+    op,
+    polys: PartialOpPolys,
+    options: PartialOpOptions,
+    last_q: int,
+):
+    """ "A helper function to perform partial operation, such as add/sub on last half (input1) to all of input0"""
+    return [
+        op(
+            context.label,
+            polys.output(part, last_q if options.output_last_q else q, unit),
+            polys.input0(part, last_q if options.input0_last_q else q, unit),
+            polys.input1(
+                0 if options.input1_first_part else part,
+                last_q if options.input1_last_q else q,
+                unit,
+            ),
+            last_q if options.op_last_q else q,
+        )
+        for part, q, unit in product(
+            range(polys.input_remaining_rns.parts),
+            range(polys.input_remaining_rns.rns),
+            range(context.units),
+        )
+    ]
+
+
+def add_last_half(
+    context: KernelContext,
+    output: Polys,
+    input0: Polys,
+    input1: Polys,
+    input_remaining_rns: Polys,
+    last_q: int,
+):
+    """Add input0 to input1 (first part)"""
+    return partial_op(
+        context,
+        pisa_op_add,
+        PartialOpPolys(output, input0, input1, input_remaining_rns),
+        PartialOpOptions(
+            output_last_q=True,
+            input0_last_q=True,
+            input1_last_q=True,
+            input1_first_part=True,
+            op_last_q=True,
+        ),
+        last_q,
+    )
+
+
+def sub_last_half(
+    context: KernelContext,
+    output: Polys,
+    input0: Polys,
+    input1: Polys,
+    input_remaining_rns: Polys,
+    last_q: int,
+):
+    """Subtract input1 (first part) with input0 (last RNS)"""
+    return partial_op(
+        context,
+        pisa_op_sub,
+        PartialOpPolys(output, input0, input1, input_remaining_rns),
+        PartialOpOptions(input0_last_q=True, input1_first_part=True),
+        last_q,
+    )
+
+
+def muli_last_half(
+    context: KernelContext,
+    output: Polys,
+    input0: Polys,
+    input1: Polys,
+    input_remaining_rns: Polys,
+    last_q: int,
+):
+    """Muli input0/1 w/input0 last RNS"""
+    return partial_op(
+        context,
+        pisa_op_muli,
+        PartialOpPolys(output, input0, input1, input_remaining_rns),
+        PartialOpOptions(input0_last_q=True),
+        last_q,
+    )

kerngen/pisa_generators/rescale.py

@@ -0,0 +1,89 @@
+# Copyright (C) 2024 Intel Corporation
+# SPDX-License-Identifier: Apache-2.0
+
+# Copyright (C) 2024 Intel Corporation
+
+"""Module containing conversions or operations from isa to p-isa."""
+
+from dataclasses import dataclass
+
+from high_parser.pisa_operations import PIsaOp, Comment
+
+from high_parser import KernelContext, HighOp, Polys
+from .partial_op import add_last_half, sub_last_half
+
+from .basic import (
+    Muli,
+    mixed_to_pisa_ops,
+    Sub,
+    split_last_rns_polys,
+    duplicate_polys,
+    common_immediates,
+)
+from .ntt import INTT, NTT
+
+
+@dataclass
+class Rescale(HighOp):
+    """Class representing mod down operation"""
+
+    context: KernelContext
+    output: Polys
+    input0: Polys
+
+    def to_pisa(self) -> list[PIsaOp]:
+        """Return the p-isa code to perform an mod switch down"""
+        # Immediates
+        last_q = self.input0.rns - 1
+        one, r2, iq = common_immediates(r2_rns=last_q, iq_rns=last_q)
+
+        q_last_half = Polys("qLastHalf", 1, self.input0.rns)
+        q_i_last_half = Polys("qiLastHalf", 1, rns=last_q)
+
+        # split input
+        input_last_rns, input_remaining_rns = split_last_rns_polys(self.input0)
+
+        # Create temp vars for input_last/remaining
+        temp_input_last_rns = duplicate_polys(input_last_rns, "y")
+        temp_input_remaining_rns = duplicate_polys(input_remaining_rns, "x")
+
+        # Compute the `delta_i = t * [-t^-1 * c_i] mod ql` where `i` are the parts
+        # The `one` acts as a select flag as whether or not R2 the Montgomery
+        # factor should be applied
+        return mixed_to_pisa_ops(
+            [
+                Comment("Start of Rescale kernel."),
+                INTT(self.context, temp_input_last_rns, input_last_rns),
+                Muli(self.context, temp_input_last_rns, temp_input_last_rns, one),
+                Comment("Add the last part of the input to y"),
+                add_last_half(
+                    self.context,
+                    temp_input_last_rns,
+                    temp_input_last_rns,
+                    q_last_half,
+                    input_remaining_rns,
+                    last_q,
+                ),
+                Comment("Subtract q_i (last half/last rns) from y"),
+                sub_last_half(
+                    self.context,
+                    temp_input_remaining_rns,
+                    temp_input_last_rns,
+                    q_i_last_half,
+                    input_remaining_rns,
+                    last_q,
+                ),
+                Muli(
+                    self.context, temp_input_remaining_rns, temp_input_remaining_rns, r2
+                ),
+                NTT(self.context, temp_input_remaining_rns, temp_input_remaining_rns),
+                Sub(
+                    self.context,
+                    temp_input_remaining_rns,
+                    Polys.from_polys(self.input0, mode="drop_last_rns"),
+                    temp_input_remaining_rns,
+                ),
+                Muli(self.context, self.output, temp_input_remaining_rns, iq),
+                Comment("End of Rescale kernel."),
+            ]
+        )