Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

feat: prefer AcirContext-native methods for performing logic operations #3898

Merged
merged 4 commits into from
Dec 21, 2023
Merged

feat: prefer AcirContext-native methods for performing logic operations #3898

Changes from all commits
Commits
Show all changes
4 commits
Select commit Hold shift + click to select a range
bed8822
feat prefer `AcirContext`-native methods for performing logic operations
TomAFrench Dec 21, 2023
a28f33a
feat: add single bit XOR implementation
TomAFrench Dec 21, 2023
73f65cf
Merge branch 'master' into tf/acir-context-logic
TomAFrench Dec 21, 2023
3b8a0e8
Merge branch 'master' into tf/acir-context-logic
TomAFrench Dec 21, 2023
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
25 changes: 16 additions & 9 deletions compiler/noirc_evaluator/src/ssa/acir_gen/acir_ir/acir_variable.rs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -383,9 +383,19 @@ impl AcirContext {
return Ok(lhs);
}

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`.
Expand Down Expand Up @@ -450,9 +460,8 @@ 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)
}
}

Expand Down Expand Up @@ -889,9 +898,7 @@ 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)?;
Expand Down
Loading