fix: fix LUT input pin orderings to be MSB to LSB in comb truth table…

… operations

Previously, Yosys Optimizer's RTLIL importer collected alphabetical pins A, B, C, (...) for truth table operations when importing the optimized RTLIL. A is the LSB and C is the MSB top bit. When converting to comb truth table ops, we place A, B, C as the inputs, while comb's truth table op expects inputs ordered from MSB to LSB. This resulted in correctness issues later in lowerings to CGGI (whose LUT op also expects MSB to LSB) and then tfhe_rust.

PiperOrigin-RevId: 603044828

include/Dialect/BUILD

@@ -0,0 +1,45 @@
+# Built-in common HEIR definitions
+
+load("@llvm-project//mlir:tblgen.bzl", "gentbl_cc_library", "td_library")
+
+package(
+    default_applicable_licenses = ["@heir//:license"],
+    default_visibility = ["//visibility:public"],
+)
+
+exports_files(
+    [
+        "HEIRInterfaces.h",
+    ],
+)
+
+td_library(
+    name = "td_files",
+    srcs = [
+        "HEIRInterfaces.td",
+    ],
+    # include from the heir-root to enable fully-qualified include-paths
+    includes = ["../.."],
+    deps = [
+        "@llvm-project//mlir:OpBaseTdFiles",
+    ],
+)
+
+gentbl_cc_library(
+    name = "interfaces_inc_gen",
+    tbl_outs = [
+        (
+            ["-gen-op-interface-decls"],
+            "HEIRInterfaces.h.inc",
+        ),
+        (
+            ["-gen-op-interface-defs"],
+            "HEIRInterfaces.cpp.inc",
+        ),
+    ],
+    tblgen = "@llvm-project//mlir:mlir-tblgen",
+    td_file = "HEIRInterfaces.td",
+    deps = [
+        ":td_files",
+    ],
+)

include/Dialect/CGGI/IR/BUILD

@@ -73,6 +73,7 @@ gentbl_cc_library(
     deps = [
         ":dialect_inc_gen",
         ":td_files",
+        "@heir//include/Dialect:td_files",
         "@heir//include/Dialect/LWE/IR:td_files",
         "@heir//include/Dialect/Polynomial/IR:td_files",
     ],

include/Dialect/CGGI/IR/CGGIOps.h

@@ -2,6 +2,7 @@
 #define HEIR_INCLUDE_DIALECT_CGGI_IR_CGGIOPS_H_
 
 #include "include/Dialect/CGGI/IR/CGGIDialect.h"
+#include "include/Dialect/HEIRInterfaces.h"
 #include "include/Dialect/LWE/IR/LWETypes.h"
 #include "mlir/include/mlir/IR/BuiltinOps.h"  // from @llvm-project
 #include "mlir/include/mlir/Interfaces/InferTypeOpInterface.h"  // from @llvm-project

include/Dialect/CGGI/IR/CGGIOps.td

@@ -1,6 +1,7 @@
 #ifndef HEIR_INCLUDE_DIALECT_CGGI_IR_CGGIOPS_TD_
 #define HEIR_INCLUDE_DIALECT_CGGI_IR_CGGIOPS_TD_
 
+include "include/Dialect/HEIRInterfaces.td"
 include "include/Dialect/CGGI/IR/CGGIDialect.td"
 
 include "include/Dialect/Polynomial/IR/PolynomialAttributes.td"
@@ -53,7 +54,9 @@ class CGGI_LutOp<string mnemonic, list<Trait> traits = []>
   Pure,
   Commutative,
   Elementwise,
-  Scalarizable
+  Scalarizable,
+  DeclareOpInterfaceMethods<LUTOpInterface>
+
 ]> {
   let results = (outs LWECiphertextLike:$output);
   let assemblyFormat = "`(` operands `)` attr-dict `:` qualified(type($output))" ;

include/Dialect/Comb/IR/BUILD

@@ -17,6 +17,7 @@ td_library(
     ],
     includes = ["../../../.."],
     deps = [
+        "@heir//include/Dialect:td_files",
         "@llvm-project//mlir:BuiltinDialectTdFiles",
         "@llvm-project//mlir:ControlFlowInterfacesTdFiles",
         "@llvm-project//mlir:FunctionInterfacesTdFiles",

include/Dialect/Comb/IR/CombOps.h

@@ -14,6 +14,7 @@
 #define HEIR_INCLUDE_DIALECT_COMB_COMBOPS_H
 
 #include "include/Dialect/Comb/IR/CombDialect.h"
+#include "include/Dialect/HEIRInterfaces.h"
 #include "mlir/include/mlir/Bytecode/BytecodeOpInterface.h"  // from @llvm-project
 #include "mlir/include/mlir/IR/BuiltinOps.h"        // from @llvm-project
 #include "mlir/include/mlir/IR/OpImplementation.h"  // from @llvm-project

include/Dialect/Comb/IR/Combinational.td

@@ -17,6 +17,8 @@
 #ifndef HEIR_INCLUDE_DIALECT_COMB_COMBINATIONAL_TD
 #define HEIR_INCLUDE_DIALECT_COMB_COMBINATIONAL_TD
 
+include "include/Dialect/HEIRInterfaces.td"
+
 include "mlir/Interfaces/InferTypeOpInterface.td"
 include "mlir/IR/BuiltinAttributes.td"
 include "mlir/IR/EnumAttr.td"
@@ -270,7 +272,7 @@ def MuxOp : CombOp<"mux",
 
 }
 
-def TruthTableOp : CombOp<"truth_table", [Pure]> {
+def TruthTableOp : CombOp<"truth_table", [Pure, DeclareOpInterfaceMethods<LUTOpInterface>]> {
   let summary = "Return a true/false based on a lookup table";
   let description = [{
     ```

include/Dialect/HEIRInterfaces.h

@@ -0,0 +1,12 @@
+#ifndef HEIR_INCLUDE_DIALECT_HEIRINTERFACES_H_
+#define HEIR_INCLUDE_DIALECT_HEIRINTERFACES_H_
+
+#include "mlir/include/mlir/IR/Builders.h"               // from @llvm-project
+#include "mlir/include/mlir/IR/BuiltinTypes.h"           // from @llvm-project
+#include "mlir/include/mlir/IR/Dialect.h"                // from @llvm-project
+#include "mlir/include/mlir/IR/DialectImplementation.h"  // from @llvm-project
+
+// Pull in HEIR interfaces
+#include "include/Dialect/HEIRInterfaces.h.inc"
+
+#endif  // HEIR_INCLUDE_DIALECT_HEIRINTERFACES_H_

include/Dialect/HEIRInterfaces.td

@@ -0,0 +1,14 @@
+include "mlir/IR/OpBase.td"
+
+def LUTOpInterface : OpInterface<"LUTOpInterface"> {
+  let description = [{
+    This is an example interface definition.
+  }];
+
+  let methods = [
+    InterfaceMethod<
+      "Gets lookup table inputs from most significant bit to least.",
+      "mlir::ValueRange", "getLookupTableInputs"
+    >,
+  ];
+}

lib/Dialect/BUILD

@@ -0,0 +1,20 @@
+# Built in HEIR declarations
+
+package(
+    default_applicable_licenses = ["@heir//:license"],
+    default_visibility = ["//visibility:public"],
+)
+
+cc_library(
+    name = "HEIRInterfaces",
+    srcs = [
+        "HEIRInterfaces.cpp",
+    ],
+    hdrs = [
+        "@heir//include/Dialect:HEIRInterfaces.h",
+    ],
+    deps = [
+        "@heir//include/Dialect:interfaces_inc_gen",
+        "@llvm-project//mlir:IR",
+    ],
+)

lib/Dialect/CGGI/IR/BUILD

@@ -7,6 +7,7 @@ cc_library(
     name = "Dialect",
     srcs = [
         "CGGIDialect.cpp",
+        "CGGIOps.cpp",
     ],
     hdrs = [
         "@heir//include/Dialect/CGGI/IR:CGGIAttributes.h",
@@ -17,6 +18,7 @@ cc_library(
         "@heir//include/Dialect/CGGI/IR:attributes_inc_gen",
         "@heir//include/Dialect/CGGI/IR:dialect_inc_gen",
         "@heir//include/Dialect/CGGI/IR:ops_inc_gen",
+        "@heir//lib/Dialect:HEIRInterfaces",
         "@heir//lib/Dialect/LWE/IR:Dialect",
         "@llvm-project//llvm:Support",
         "@llvm-project//mlir:IR",

lib/Dialect/CGGI/IR/CGGIOps.cpp

@@ -0,0 +1,19 @@
+#include "include/Dialect/CGGI/IR/CGGIOps.h"
+
+#include "mlir/include/mlir/IR/ValueRange.h"  // from @llvm-project
+
+namespace mlir {
+namespace heir {
+namespace cggi {
+
+mlir::ValueRange Lut2Op::getLookupTableInputs() {
+  return mlir::ValueRange{getB(), getA()};
+}
+
+mlir::ValueRange Lut3Op::getLookupTableInputs() {
+  return mlir::ValueRange{getC(), getB(), getA()};
+}
+
+}  // namespace cggi
+}  // namespace heir
+}  // namespace mlir

lib/Dialect/Comb/IR/BUILD

@@ -18,6 +18,7 @@ cc_library(
         "@heir//include/Dialect/Comb/IR:enum_inc_gen",
         "@heir//include/Dialect/Comb/IR:ops_inc_gen",
         "@heir//include/Dialect/Comb/IR:type_inc_gen",
+        "@heir//lib/Dialect:HEIRInterfaces",
         "@llvm-project//llvm:Support",
         "@llvm-project//mlir:ControlFlowInterfaces",
         "@llvm-project//mlir:FunctionInterfaces",

lib/Dialect/Comb/IR/CombOps.cpp

@@ -227,6 +227,10 @@ LogicalResult TruthTableOp::verify() {
   return success();
 }
 
+mlir::ValueRange TruthTableOp::getLookupTableInputs() {
+  return mlir::ValueRange{getInputs()};
+}
+
 }  // namespace comb
 }  // namespace heir
 }  // namespace mlir

lib/Dialect/HEIRInterfaces.cpp

@@ -0,0 +1,6 @@
+// Block clang-format from thinking the header is unused
+// IWYU pragma: begin_keep
+#include "include/Dialect/HEIRInterfaces.h"
+// IWYU pragma: end_keep
+
+#include "include/Dialect/HEIRInterfaces.cpp.inc"

lib/Transforms/YosysOptimizer/LUTImporter.cpp

@@ -48,7 +48,14 @@ SmallVector<Yosys::RTLIL::SigSpec, 4> LUTImporter::getInputs(
     }
     inputs.push_back(conn.second);
   }
-  return inputs;
+  // Alphabetical order gives LSB to MSB, but LUT operations order their inputs
+  // from MSB to LSB.
+  SmallVector<Yosys::RTLIL::SigSpec, 4> reversed;
+  reversed.reserve(inputs.size());
+  for (unsigned i = 0; i < inputs.size(); i++) {
+    reversed.push_back(inputs[inputs.size() - i - 1]);
+  }
+  return reversed;
 }
 
 Yosys::RTLIL::SigSpec LUTImporter::getOutput(Yosys::RTLIL::Cell *cell) const {

tests/tfhe_rust/end_to_end/src/main_add_one.rs

@@ -1,6 +1,6 @@
 use clap::Parser;
-use tfhe::shortint::*;
 use tfhe::shortint::parameters::get_parameters_from_message_and_carry;
+use tfhe::shortint::*;
 
 mod fn_under_test;
 
@@ -33,20 +33,22 @@ pub fn decrypt(ciphertexts: &[Ciphertext], client_key: &ClientKey) -> u8 {
     let mut accum = 0u8;
     for (i, ct) in ciphertexts.iter().enumerate() {
         let bit = client_key.decrypt(ct);
-        accum |= (bit as u8) << i;
+        // TODO(403): Fix the ordering of the output bits in Yosys Optimizer
+        accum |= (bit as u8) << (7 - i);
     }
     accum
 }
 
 fn main() {
     let flags = Args::parse();
-    let parameters = get_parameters_from_message_and_carry((1 << flags.message_bits) - 1, flags.carry_bits);
+    let parameters =
+        get_parameters_from_message_and_carry((1 << flags.message_bits) - 1, flags.carry_bits);
     let (client_key, server_key) = tfhe::shortint::gen_keys(parameters);
 
     let ct_1 = encrypt(flags.input1.into(), &client_key);
 
     let result = fn_under_test::fn_under_test(&server_key, &ct_1);
     let output = decrypt(&result, &client_key);
 
-    println!("{:?}", output);
+    println!("{:08b}", output);
 }

tests/tfhe_rust/end_to_end/test_add_one.mlir

@@ -5,7 +5,8 @@
 !ct_ty = !lwe.lwe_ciphertext<encoding = #encoding>
 !pt_ty = !lwe.lwe_plaintext<encoding = #encoding>
 
-// CHECK: 3
+// CHECK: 00000011
+module {
   func.func @fn_under_test(%arg0: tensor<8x!ct_ty>) -> tensor<8x!ct_ty> {
     %true = arith.constant true
     %false = arith.constant false
@@ -17,63 +18,34 @@
     %c2 = arith.constant 2 : index
     %c1 = arith.constant 1 : index
     %c0 = arith.constant 0 : index
-    %extracted = tensor.extract %arg0[%c0] : tensor<8x!ct_ty>
-    %0 = lwe.encode %true {encoding = #encoding} : i1 to !pt_ty
-    %1 = lwe.trivial_encrypt %0 : !pt_ty to !ct_ty
-    %2 = lwe.encode %false {encoding = #encoding} : i1 to !pt_ty
-    %3 = lwe.trivial_encrypt %2 : !pt_ty to !ct_ty
-    %4 = cggi.lut3(%extracted, %1, %3) {lookup_table = 8 : ui8} : !ct_ty
-    %extracted_0 = tensor.extract %arg0[%c1] : tensor<8x!ct_ty>
-    %5 = lwe.encode %false {encoding = #encoding} : i1 to !pt_ty
-    %6 = lwe.trivial_encrypt %5 : !pt_ty to !ct_ty
-    %7 = cggi.lut3(%4, %extracted_0, %6) {lookup_table = 150 : ui8} : !ct_ty
-    %8 = lwe.encode %false {encoding = #encoding} : i1 to !pt_ty
-    %9 = lwe.trivial_encrypt %8 : !pt_ty to !ct_ty
-    %10 = cggi.lut3(%4, %extracted_0, %9) {lookup_table = 23 : ui8} : !ct_ty
-    %extracted_1 = tensor.extract %arg0[%c2] : tensor<8x!ct_ty>
-    %11 = lwe.encode %false {encoding = #encoding} : i1 to !pt_ty
-    %12 = lwe.trivial_encrypt %11 : !pt_ty to !ct_ty
-    %13 = cggi.lut3(%10, %extracted_1, %12) {lookup_table = 43 : ui8} : !ct_ty
-    %extracted_2 = tensor.extract %arg0[%c3] : tensor<8x!ct_ty>
-    %14 = lwe.encode %false {encoding = #encoding} : i1 to !pt_ty
-    %15 = lwe.trivial_encrypt %14 : !pt_ty to !ct_ty
-    %16 = cggi.lut3(%13, %extracted_2, %15) {lookup_table = 43 : ui8} : !ct_ty
-    %extracted_3 = tensor.extract %arg0[%c4] : tensor<8x!ct_ty>
-    %17 = lwe.encode %false {encoding = #encoding} : i1 to !pt_ty
-    %18 = lwe.trivial_encrypt %17 : !pt_ty to !ct_ty
-    %19 = cggi.lut3(%16, %extracted_3, %18) {lookup_table = 43 : ui8} : !ct_ty
-    %extracted_4 = tensor.extract %arg0[%c5] : tensor<8x!ct_ty>
-    %20 = lwe.encode %false {encoding = #encoding} : i1 to !pt_ty
-    %21 = lwe.trivial_encrypt %20 : !pt_ty to !ct_ty
-    %22 = cggi.lut3(%19, %extracted_4, %21) {lookup_table = 43 : ui8} : !ct_ty
-    %extracted_5 = tensor.extract %arg0[%c6] : tensor<8x!ct_ty>
-    %23 = lwe.encode %false {encoding = #encoding} : i1 to !pt_ty
-    %24 = lwe.trivial_encrypt %23 : !pt_ty to !ct_ty
-    %25 = cggi.lut3(%22, %extracted_5, %24) {lookup_table = 105 : ui8} : !ct_ty
-    %26 = lwe.encode %false {encoding = #encoding} : i1 to !pt_ty
-    %27 = lwe.trivial_encrypt %26 : !pt_ty to !ct_ty
-    %28 = cggi.lut3(%22, %extracted_5, %27) {lookup_table = 43 : ui8} : !ct_ty
-    %extracted_6 = tensor.extract %arg0[%c7] : tensor<8x!ct_ty>
-    %29 = lwe.encode %false {encoding = #encoding} : i1 to !pt_ty
-    %30 = lwe.trivial_encrypt %29 : !pt_ty to !ct_ty
-    %31 = cggi.lut3(%28, %extracted_6, %30) {lookup_table = 105 : ui8} : !ct_ty
-    %32 = lwe.encode %true {encoding = #encoding} : i1 to !pt_ty
-    %33 = lwe.trivial_encrypt %32 : !pt_ty to !ct_ty
-    %34 = lwe.encode %false {encoding = #encoding} : i1 to !pt_ty
-    %35 = lwe.trivial_encrypt %34 : !pt_ty to !ct_ty
-    %36 = cggi.lut3(%extracted, %33, %35) {lookup_table = 6 : ui8} : !ct_ty
-    %37 = lwe.encode %false {encoding = #encoding} : i1 to !pt_ty
-    %38 = lwe.trivial_encrypt %37 : !pt_ty to !ct_ty
-    %39 = cggi.lut3(%10, %extracted_1, %38) {lookup_table = 105 : ui8} : !ct_ty
-    %40 = lwe.encode %false {encoding = #encoding} : i1 to !pt_ty
-    %41 = lwe.trivial_encrypt %40 : !pt_ty to !ct_ty
-    %42 = cggi.lut3(%13, %extracted_2, %41) {lookup_table = 105 : ui8} : !ct_ty
-    %43 = lwe.encode %false {encoding = #encoding} : i1 to !pt_ty
-    %44 = lwe.trivial_encrypt %43 : !pt_ty to !ct_ty
-    %45 = cggi.lut3(%16, %extracted_3, %44) {lookup_table = 105 : ui8} : !ct_ty
-    %46 = lwe.encode %false {encoding = #encoding} : i1 to !pt_ty
-    %47 = lwe.trivial_encrypt %46 : !pt_ty to !ct_ty
-    %48 = cggi.lut3(%19, %extracted_4, %47) {lookup_table = 105 : ui8} : !ct_ty
-    %from_elements = tensor.from_elements %31, %25, %48, %45, %42, %39, %7, %36 : tensor<8x!ct_ty>
+    %0 = tensor.extract %arg0[%c0] : tensor<8x!ct_ty>
+    %1 = lwe.encode %false {encoding = #encoding} : i1 to !pt_ty
+    %2 = lwe.trivial_encrypt %1 : !pt_ty to !ct_ty
+    %3 = lwe.encode %true {encoding = #encoding} : i1 to !pt_ty
+    %4 = lwe.trivial_encrypt %3 : !pt_ty to !ct_ty
+    %5 = cggi.lut3(%2, %4, %0) {lookup_table = 8 : ui8} : !ct_ty
+    %6 = tensor.extract %arg0[%c1] : tensor<8x!ct_ty>
+    %7 = cggi.lut3(%2, %6, %5) {lookup_table = 150 : ui8} : !ct_ty
+    %8 = cggi.lut3(%2, %6, %5) {lookup_table = 23 : ui8} : !ct_ty
+    %9 = tensor.extract %arg0[%c2] : tensor<8x!ct_ty>
+    %10 = cggi.lut3(%2, %9, %8) {lookup_table = 43 : ui8} : !ct_ty
+    %11 = tensor.extract %arg0[%c3] : tensor<8x!ct_ty>
+    %12 = cggi.lut3(%2, %11, %10) {lookup_table = 43 : ui8} : !ct_ty
+    %13 = tensor.extract %arg0[%c4] : tensor<8x!ct_ty>
+    %14 = cggi.lut3(%2, %13, %12) {lookup_table = 43 : ui8} : !ct_ty
+    %15 = tensor.extract %arg0[%c5] : tensor<8x!ct_ty>
+    %16 = cggi.lut3(%2, %15, %14) {lookup_table = 43 : ui8} : !ct_ty
+    %17 = tensor.extract %arg0[%c6] : tensor<8x!ct_ty>
+    %18 = cggi.lut3(%2, %17, %16) {lookup_table = 105 : ui8} : !ct_ty
+    %19 = cggi.lut3(%2, %17, %16) {lookup_table = 43 : ui8} : !ct_ty
+    %20 = tensor.extract %arg0[%c7] : tensor<8x!ct_ty>
+    %21 = cggi.lut3(%2, %20, %19) {lookup_table = 105 : ui8} : !ct_ty
+    %22 = cggi.lut3(%2, %4, %0) {lookup_table = 6 : ui8} : !ct_ty
+    %23 = cggi.lut3(%2, %9, %8) {lookup_table = 105 : ui8} : !ct_ty
+    %24 = cggi.lut3(%2, %11, %10) {lookup_table = 105 : ui8} : !ct_ty
+    %25 = cggi.lut3(%2, %13, %12) {lookup_table = 105 : ui8} : !ct_ty
+    %26 = cggi.lut3(%2, %15, %14) {lookup_table = 105 : ui8} : !ct_ty
+    %from_elements = tensor.from_elements %21, %18, %26, %25, %24, %23, %7, %22 : tensor<8x!ct_ty>
     return %from_elements : tensor<8x!ct_ty>
   }
+}