From 457c985a924c9713d9fdaf527c5f2e4336414d7c Mon Sep 17 00:00:00 2001
From: Bobbin Threadbare <bobbinth@protonmail.com>
Date: Fri, 5 Jan 2024 22:06:55 -0800
Subject: [PATCH] refactor: remove sve feature flag

---
 Cargo.toml                  | 1 -
 README.md                   | 4 ++--
 build.rs                    | 4 ++--
 src/hash/rescue/arch/mod.rs | 4 ++--
 4 files changed, 6 insertions(+), 7 deletions(-)

diff --git a/Cargo.toml b/Cargo.toml
index a8a0fd0..008936f 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -36,7 +36,6 @@ default = ["std"]
 executable = ["dep:clap", "dep:rand_utils", "std"]
 serde = ["dep:serde", "serde?/alloc", "winter_math/serde"]
 std = ["blake3/std", "dep:cc", "dep:libc", "winter_crypto/std", "winter_math/std", "winter_utils/std"]
-sve = ["std"]
 
 [dependencies]
 blake3 = { version = "1.5", default-features = false }
diff --git a/README.md b/README.md
index 3b04dc1..5fcb8d3 100644
--- a/README.md
+++ b/README.md
@@ -53,9 +53,9 @@ RUSTFLAGS="-C target-feature=+avx2" cargo build --release
 ```
 
 ### SVE acceleration
-On platforms with [SVE](https://en.wikipedia.org/wiki/AArch64#Scalable_Vector_Extension_(SVE)) support, RPO and RPX hash function can be accelerated by using the vector processing unit. To enable SVE acceleration, the code needs to be compiled with the `sve` feature enabled. This feature has an effect only if the platform exposes `target-feature=sve` flag. On some platforms (e.g., Graviton 3), for this flag to be set, the compilation must be done in "native" mode. For example, to enable SVE acceleration on Graviton 3, we can execute the following:
+On platforms with [SVE](https://en.wikipedia.org/wiki/AArch64#Scalable_Vector_Extension_(SVE)) support, RPO and RPX hash function can be accelerated by using the vector processing unit. To enable SVE acceleration, the code needs to be compiled with the `sve` target feature enabled. For example:
 ```shell
-RUSTFLAGS="-C target-cpu=native" cargo build --release --features sve
+ RUSTFLAGS="-C target-feature=+sve" cargo build --release
 ```
 
 ## Testing
diff --git a/build.rs b/build.rs
index 8fbd225..2e71359 100644
--- a/build.rs
+++ b/build.rs
@@ -2,7 +2,7 @@ fn main() {
     #[cfg(feature = "std")]
     compile_rpo_falcon();
 
-    #[cfg(all(target_feature = "sve", feature = "sve"))]
+    #[cfg(target_feature = "sve")]
     compile_arch_arm64_sve();
 }
 
@@ -34,7 +34,7 @@ fn compile_rpo_falcon() {
         .compile("rpo_falcon512");
 }
 
-#[cfg(all(target_feature = "sve", feature = "sve"))]
+#[cfg(target_feature = "sve")]
 fn compile_arch_arm64_sve() {
     const RPO_SVE_PATH: &str = "arch/arm64-sve/rpo";
 
diff --git a/src/hash/rescue/arch/mod.rs b/src/hash/rescue/arch/mod.rs
index 6706363..9d82cf8 100644
--- a/src/hash/rescue/arch/mod.rs
+++ b/src/hash/rescue/arch/mod.rs
@@ -1,4 +1,4 @@
-#[cfg(all(target_feature = "sve", feature = "sve"))]
+#[cfg(target_feature = "sve")]
 pub mod optimized {
     use crate::hash::rescue::STATE_WIDTH;
     use crate::Felt;
@@ -78,7 +78,7 @@ pub mod optimized {
     }
 }
 
-#[cfg(not(any(target_feature = "avx2", all(target_feature = "sve", feature = "sve"))))]
+#[cfg(not(any(target_feature = "avx2", target_feature = "sve")))]
 pub mod optimized {
     use crate::hash::rescue::STATE_WIDTH;
     use crate::Felt;