From bed8822260dc454c7bd4e0ea1d807297eef7a65d Mon Sep 17 00:00:00 2001 From: Tom French Date: Thu, 21 Dec 2023 11:58:25 +0000 Subject: [PATCH 1/2] feat prefer `AcirContext`-native methods for performing logic operations --- .../src/ssa/acir_gen/acir_ir/acir_variable.rs | 9 +++------ 1 file changed, 3 insertions(+), 6 deletions(-) diff --git a/compiler/noirc_evaluator/src/ssa/acir_gen/acir_ir/acir_variable.rs b/compiler/noirc_evaluator/src/ssa/acir_gen/acir_ir/acir_variable.rs index 05a22ab6aad..9d8c714cd18 100644 --- a/compiler/noirc_evaluator/src/ssa/acir_gen/acir_ir/acir_variable.rs +++ b/compiler/noirc_evaluator/src/ssa/acir_gen/acir_ir/acir_variable.rs @@ -413,9 +413,8 @@ impl AcirContext { let max = self.add_constant((1_u128 << bit_size) - 1); let a = self.sub_var(max, lhs)?; let b = self.sub_var(max, rhs)?; - let inputs = vec![AcirValue::Var(a, typ.clone()), AcirValue::Var(b, typ)]; - let outputs = self.black_box_function(BlackBoxFunc::AND, inputs, 1)?; - self.sub_var(max, outputs[0]) + let a_and_b = self.and_var(a, b, typ)?; + self.sub_var(max, a_and_b) } } @@ -852,9 +851,7 @@ impl AcirContext { // Unsigned to signed: derive q and r from q1,r1 and the signs of lhs and rhs // Quotient sign is lhs sign * rhs sign, whose resulting sign bit is the XOR of the sign bits - let sign_sum = self.add_var(lhs_leading, rhs_leading)?; - let sign_prod = self.mul_var(lhs_leading, rhs_leading)?; - let q_sign = self.add_mul_var(sign_sum, -FieldElement::from(2_i128), sign_prod)?; + let q_sign = self.xor_var(lhs_leading, rhs_leading, AcirType::unsigned(1))?; let quotient = self.two_complement(q1, q_sign, bit_size)?; let remainder = self.two_complement(r1, lhs_leading, bit_size)?; From a28f33a80d419f6bce320be9122ccd051d287f48 Mon Sep 17 00:00:00 2001 From: Tom French Date: Thu, 21 Dec 2023 12:09:55 +0000 Subject: [PATCH 2/2] feat: add single bit XOR implementation --- .../src/ssa/acir_gen/acir_ir/acir_variable.rs | 16 +++++++++++++--- 1 file changed, 13 insertions(+), 3 deletions(-) diff --git a/compiler/noirc_evaluator/src/ssa/acir_gen/acir_ir/acir_variable.rs b/compiler/noirc_evaluator/src/ssa/acir_gen/acir_ir/acir_variable.rs index 9d8c714cd18..94736d7b3e3 100644 --- a/compiler/noirc_evaluator/src/ssa/acir_gen/acir_ir/acir_variable.rs +++ b/compiler/noirc_evaluator/src/ssa/acir_gen/acir_ir/acir_variable.rs @@ -368,9 +368,19 @@ impl AcirContext { rhs: AcirVar, typ: AcirType, ) -> Result { - let inputs = vec![AcirValue::Var(lhs, typ.clone()), AcirValue::Var(rhs, typ)]; - let outputs = self.black_box_function(BlackBoxFunc::XOR, inputs, 1)?; - Ok(outputs[0]) + let bit_size = typ.bit_size(); + if bit_size == 1 { + // Operands are booleans. + // + // a ^ b == a + b - 2*a*b + let sum = self.add_var(lhs, rhs)?; + let prod = self.mul_var(lhs, rhs)?; + self.add_mul_var(sum, -FieldElement::from(2_i128), prod) + } else { + let inputs = vec![AcirValue::Var(lhs, typ.clone()), AcirValue::Var(rhs, typ)]; + let outputs = self.black_box_function(BlackBoxFunc::XOR, inputs, 1)?; + Ok(outputs[0]) + } } /// Returns an `AcirVar` that is the AND result of `lhs` & `rhs`.