no longer using iter_array_chunks in non-prover builds

Author: ohad-agadi

crates/stwo/src/core/fri.rs

@@ -726,9 +726,9 @@ pub fn fold_line(
 
     let folded_values = eval
         .iter()
-        .array_chunks()
+        .tuples()
         .enumerate()
-        .map(|(i, [&f_x, &f_neg_x])| {
+        .map(|(i, (&f_x, &f_neg_x))| {
             // TODO(andrew): Inefficient. Update when domain twiddles get stored in a buffer.
             let x = domain.at(bit_reverse_index(i << FOLD_STEP, domain.log_size()));
 
@@ -755,9 +755,9 @@ pub fn fold_circle_into_line(
     let alpha_sq = alpha * alpha;
 
     src.iter()
-        .array_chunks()
+        .tuples()
         .enumerate()
-        .for_each(|(i, [&f_p, &f_neg_p])| {
+        .for_each(|(i, (&f_p, &f_neg_p))| {
             // TODO(andrew): Inefficient. Update when domain twiddles get stored in a buffer.
             let p = src_domain.at(bit_reverse_index(
                 i << CIRCLE_TO_LINE_FOLD_STEP,

crates/stwo/src/lib.rs

@@ -4,13 +4,10 @@
     feature(stdarch_x86_avx512)
 )]
 #![cfg_attr(not(feature = "std"), no_std)]
-#![feature(
-    array_chunks,
-    array_try_from_fn,
-    int_roundings,
-    iter_array_chunks,
-    portable_simd,
-    slice_ptr_get
+#![feature(array_try_from_fn)]
+#![cfg_attr(
+    feature = "prover",
+    feature(array_chunks, iter_array_chunks, portable_simd, slice_ptr_get)
 )]
 pub mod core;