Fix AVX2 and AVX-512 builds (#419)

Build was broken by 5758b8c.
This adds a regression test to CI so it doesn't happen again

.github/workflows/rust.yml

@@ -26,13 +26,19 @@ jobs:
     - uses: dtolnay/rust-toolchain@stable
     - run: cargo test --no-default-features --features "std u64_backend"
 
-  test-simd:
-    name: Test simd backend (nightly)
+  build-simd:
+    name: Build simd backend (nightly)
     runs-on: ubuntu-latest
     steps:
     - uses: actions/checkout@v3
     - uses: dtolnay/rust-toolchain@nightly
-    - run: cargo test --no-default-features --features "std simd_backend"
+    # Build with AVX2 features, then with AVX512 features
+    - env:
+        RUSTFLAGS: "-C target_feature=+avx2"
+      run: cargo build --no-default-features --features "std simd_backend"
+    - env:
+        RUSTFLAGS: "-C target_feature=+avx512ifma"
+      run: cargo build --no-default-features --features "std simd_backend"
 
   test-defaults-serde:
     name: Test default feature selection and serde

src/backend/vector/avx2/constants.rs

@@ -13,9 +13,9 @@
 
 use packed_simd::u32x8;
 
-use backend::vector::avx2::edwards::{CachedPoint, ExtendedPoint};
-use backend::vector::avx2::field::FieldElement2625x4;
-use window::NafLookupTable8;
+use crate::backend::vector::avx2::edwards::{CachedPoint, ExtendedPoint};
+use crate::backend::vector::avx2::field::FieldElement2625x4;
+use crate::window::NafLookupTable8;
 
 /// The identity element as an `ExtendedPoint`.
 pub(crate) static EXTENDEDPOINT_IDENTITY: ExtendedPoint = ExtendedPoint(FieldElement2625x4([

src/backend/vector/avx2/edwards.rs

@@ -41,10 +41,10 @@ use core::ops::{Add, Neg, Sub};
 use subtle::Choice;
 use subtle::ConditionallySelectable;
 
-use edwards;
-use window::{LookupTable, NafLookupTable5, NafLookupTable8};
+use crate::edwards;
+use crate::window::{LookupTable, NafLookupTable5, NafLookupTable8};
 
-use traits::Identity;
+use crate::traits::Identity;
 
 use super::constants;
 use super::field::{FieldElement2625x4, Lanes, Shuffle};
@@ -330,7 +330,7 @@ mod test {
     use super::*;
 
     fn serial_add(P: edwards::EdwardsPoint, Q: edwards::EdwardsPoint) -> edwards::EdwardsPoint {
-        use backend::serial::u64::field::FieldElement51;
+        use crate::backend::serial::u64::field::FieldElement51;
 
         let (X1, Y1, Z1, T1) = (P.X, P.Y, P.Z, P.T);
         let (X2, Y2, Z2, T2) = (Q.X, Q.Y, Q.Z, Q.T);
@@ -420,8 +420,8 @@ mod test {
 
     #[test]
     fn vector_addition_vs_serial_addition_vs_edwards_extendedpoint() {
-        use constants;
-        use scalar::Scalar;
+        use crate::constants;
+        use crate::scalar::Scalar;
 
         println!("Testing id +- id");
         let P = edwards::EdwardsPoint::identity();
@@ -507,8 +507,8 @@ mod test {
 
     #[test]
     fn vector_doubling_vs_serial_doubling_vs_edwards_extendedpoint() {
-        use constants;
-        use scalar::Scalar;
+        use crate::constants;
+        use crate::scalar::Scalar;
 
         println!("Testing [2]id");
         let P = edwards::EdwardsPoint::identity();
@@ -525,8 +525,8 @@ mod test {
 
     #[test]
     fn basepoint_odd_lookup_table_verify() {
-        use constants;
-        use backend::vector::avx2::constants::{BASEPOINT_ODD_LOOKUP_TABLE};
+        use crate::constants;
+        use crate::backend::vector::avx2::constants::{BASEPOINT_ODD_LOOKUP_TABLE};
 
         let basepoint_odd_table = NafLookupTable8::<CachedPoint>::from(&constants::ED25519_BASEPOINT_POINT);
         println!("basepoint_odd_lookup_table = {:?}", basepoint_odd_table);

src/backend/vector/avx2/field.rs

@@ -43,8 +43,10 @@ const D_LANES64: u8 = 0b11_00_00_00;
 use core::ops::{Add, Mul, Neg};
 use packed_simd::{i32x8, u32x8, u64x4, IntoBits};
 
-use backend::vector::avx2::constants::{P_TIMES_16_HI, P_TIMES_16_LO, P_TIMES_2_HI, P_TIMES_2_LO};
-use backend::serial::u64::field::FieldElement51;
+use crate::backend::vector::avx2::constants::{
+    P_TIMES_16_HI, P_TIMES_16_LO, P_TIMES_2_HI, P_TIMES_2_LO,
+};
+use crate::backend::serial::u64::field::FieldElement51;
 
 /// Unpack 32-bit lanes into 64-bit lanes:
 /// ```ascii,no_run

src/backend/vector/ifma/constants.rs

@@ -11,7 +11,7 @@
 
 use packed_simd::u64x4;
 
-use window::NafLookupTable8;
+use crate::window::NafLookupTable8;
 
 use super::edwards::{CachedPoint, ExtendedPoint};
 use super::field::{F51x4Reduced, F51x4Unreduced};

src/backend/vector/ifma/edwards.rs

@@ -9,15 +9,15 @@
 
 #![allow(non_snake_case)]
 
-use traits::Identity;
+use crate::traits::Identity;
 
 use std::ops::{Add, Neg, Sub};
 
 use subtle::Choice;
 use subtle::ConditionallySelectable;
 
-use edwards;
-use window::{LookupTable, NafLookupTable5, NafLookupTable8};
+use crate::edwards;
+use crate::window::{LookupTable, NafLookupTable5, NafLookupTable8};
 
 use super::constants;
 use super::field::{F51x4Reduced, F51x4Unreduced, Lanes, Shuffle};
@@ -258,8 +258,8 @@ mod test {
 
     #[test]
     fn vector_addition_vs_serial_addition_vs_edwards_extendedpoint() {
-        use constants;
-        use scalar::Scalar;
+        use crate::constants;
+        use crate::scalar::Scalar;
 
         println!("Testing id +- id");
         let P = edwards::EdwardsPoint::identity();
@@ -297,8 +297,8 @@ mod test {
 
     #[test]
     fn vector_doubling_vs_serial_doubling_vs_edwards_extendedpoint() {
-        use constants;
-        use scalar::Scalar;
+        use crate::constants;
+        use crate::scalar::Scalar;
 
         println!("Testing [2]id");
         let P = edwards::EdwardsPoint::identity();

src/backend/vector/ifma/field.rs

@@ -14,7 +14,7 @@
 use core::ops::{Add, Mul, Neg};
 use packed_simd::{u64x4, IntoBits};
 
-use backend::serial::u64::field::FieldElement51;
+use crate::backend::serial::u64::field::FieldElement51;
 
 /// A wrapper around `vpmadd52luq` that works on `u64x4`.
 #[inline(always)]

src/backend/vector/scalar_mul/pippenger.rs

@@ -11,13 +11,13 @@
 
 use core::borrow::Borrow;
 
-use backend::vector::{CachedPoint, ExtendedPoint};
-use edwards::EdwardsPoint;
-use scalar::Scalar;
-use traits::{Identity, VartimeMultiscalarMul};
+use crate::backend::vector::{CachedPoint, ExtendedPoint};
+use crate::edwards::EdwardsPoint;
+use crate::scalar::Scalar;
+use crate::traits::{Identity, VartimeMultiscalarMul};
 
 #[allow(unused_imports)]
-use prelude::*;
+use crate::prelude::*;
 
 /// Implements a version of Pippenger's algorithm.
 ///
@@ -50,9 +50,7 @@ impl VartimeMultiscalarMul for Pippenger {
 
         // Collect optimized scalars and points in a buffer for repeated access
         // (scanning the whole collection per each digit position).
-        let scalars = scalars
-            .into_iter()
-            .map(|s| s.borrow().to_radix_2w(w));
+        let scalars = scalars.into_iter().map(|s| s.borrow().to_radix_2w(w));
 
         let points = points
             .into_iter()
@@ -127,8 +125,8 @@ impl VartimeMultiscalarMul for Pippenger {
 #[cfg(test)]
 mod test {
     use super::*;
-    use constants;
-    use scalar::Scalar;
+    use crate::constants;
+    use crate::scalar::Scalar;
 
     #[test]
     fn test_vartime_pippenger() {

src/backend/vector/scalar_mul/precomputed_straus.rs

@@ -13,15 +13,15 @@
 
 use core::borrow::Borrow;
 
-use backend::vector::{CachedPoint, ExtendedPoint};
-use edwards::EdwardsPoint;
-use scalar::Scalar;
-use traits::Identity;
-use traits::VartimePrecomputedMultiscalarMul;
-use window::{NafLookupTable5, NafLookupTable8};
+use crate::backend::vector::{CachedPoint, ExtendedPoint};
+use crate::edwards::EdwardsPoint;
+use crate::scalar::Scalar;
+use crate::traits::Identity;
+use crate::traits::VartimePrecomputedMultiscalarMul;
+use crate::window::{NafLookupTable5, NafLookupTable8};
 
 #[allow(unused_imports)]
-use prelude::*;
+use crate::prelude::*;
 
 
 pub struct VartimePrecomputedStraus {

src/backend/vector/scalar_mul/straus.rs

@@ -15,14 +15,14 @@ use core::borrow::Borrow;
 
 use zeroize::Zeroizing;
 
-use backend::vector::{CachedPoint, ExtendedPoint};
-use edwards::EdwardsPoint;
-use scalar::Scalar;
-use window::{LookupTable, NafLookupTable5};
-use traits::{Identity, MultiscalarMul, VartimeMultiscalarMul};
+use crate::backend::vector::{CachedPoint, ExtendedPoint};
+use crate::edwards::EdwardsPoint;
+use crate::scalar::Scalar;
+use crate::window::{LookupTable, NafLookupTable5};
+use crate::traits::{Identity, MultiscalarMul, VartimeMultiscalarMul};
 
 #[allow(unused_imports)]
-use prelude::*;
+use crate::prelude::*;
 
 /// Multiscalar multiplication using interleaved window / Straus'
 /// method.  See the `Straus` struct in the serial backend for more

src/backend/vector/scalar_mul/variable_base.rs

@@ -1,10 +1,10 @@
 #![allow(non_snake_case)]
 
-use backend::vector::{CachedPoint, ExtendedPoint};
-use edwards::EdwardsPoint;
-use scalar::Scalar;
-use traits::Identity;
-use window::LookupTable;
+use crate::backend::vector::{CachedPoint, ExtendedPoint};
+use crate::edwards::EdwardsPoint;
+use crate::scalar::Scalar;
+use crate::traits::Identity;
+use crate::window::LookupTable;
 
 /// Perform constant-time, variable-base scalar multiplication.
 pub fn mul(point: &EdwardsPoint, scalar: &Scalar) -> EdwardsPoint {

src/backend/vector/scalar_mul/vartime_double_base.rs

@@ -11,12 +11,12 @@
 
 #![allow(non_snake_case)]
 
-use backend::vector::BASEPOINT_ODD_LOOKUP_TABLE;
-use backend::vector::{CachedPoint, ExtendedPoint};
-use edwards::EdwardsPoint;
-use scalar::Scalar;
-use traits::Identity;
-use window::NafLookupTable5;
+use crate::backend::vector::BASEPOINT_ODD_LOOKUP_TABLE;
+use crate::backend::vector::{CachedPoint, ExtendedPoint};
+use crate::edwards::EdwardsPoint;
+use crate::scalar::Scalar;
+use crate::traits::Identity;
+use crate::window::NafLookupTable5;
 
 /// Compute \\(aA + bB\\) in variable time, where \\(B\\) is the Ed25519 basepoint.
 pub fn mul(a: &Scalar, A: &EdwardsPoint, b: &Scalar) -> EdwardsPoint {

src/edwards.rs

@@ -148,7 +148,7 @@ use crate::backend::serial::scalar_mul;
     feature = "simd_backend",
     any(target_feature = "avx2", target_feature = "avx512ifma")
 ))]
-use backend::vector::scalar_mul;
+use crate::backend::vector::scalar_mul;
 
 // ------------------------------------------------------------------------
 // Compressed points

src/ristretto.rs

@@ -202,7 +202,7 @@ use crate::backend::serial::scalar_mul;
     feature = "simd_backend",
     any(target_feature = "avx2", target_feature = "avx512ifma")
 ))]
-use backend::vector::scalar_mul;
+use crate::backend::vector::scalar_mul;
 
 // ------------------------------------------------------------------------
 // Compressed points