From 52c503ba8f68264cf765e597c337ac71fda74582 Mon Sep 17 00:00:00 2001
From: laurent <laurent.mazare@gmail.com>
Date: Fri, 23 Jun 2023 12:20:16 +0100
Subject: [PATCH] Handle the contiguous case in an optimized way when copying
 cpu memory.

---
 src/cpu_backend.rs | 20 ++++++++++++++------
 1 file changed, 14 insertions(+), 6 deletions(-)

diff --git a/src/cpu_backend.rs b/src/cpu_backend.rs
index bf372589..f4055173 100644
--- a/src/cpu_backend.rs
+++ b/src/cpu_backend.rs
@@ -115,17 +115,25 @@ impl CpuStorage {
         src_stride: &[usize],
         dst_offset: usize,
     ) -> Result<()> {
-        // TODO: Optimize the contiguous case.
-        let src_indexes = StridedIndex::new(src_shape.dims(), src_stride);
         match (self, dst) {
             (Self::F32(src), Self::F32(dst)) => {
-                for (dst_index, src_index) in src_indexes.enumerate() {
-                    dst[dst_index + dst_offset] = src[src_index]
+                if src_shape.is_contiguous(src_stride) {
+                    dst[dst_offset..].copy_from_slice(src)
+                } else {
+                    let src_indexes = StridedIndex::new(src_shape.dims(), src_stride);
+                    for (dst_index, src_index) in src_indexes.enumerate() {
+                        dst[dst_index + dst_offset] = src[src_index]
+                    }
                 }
             }
             (Self::F64(src), Self::F64(dst)) => {
-                for (dst_index, src_index) in src_indexes.enumerate() {
-                    dst[dst_index + dst_offset] = src[src_index]
+                if src_shape.is_contiguous(src_stride) {
+                    dst[dst_offset..].copy_from_slice(src)
+                } else {
+                    let src_indexes = StridedIndex::new(src_shape.dims(), src_stride);
+                    for (dst_index, src_index) in src_indexes.enumerate() {
+                        dst[dst_index + dst_offset] = src[src_index]
+                    }
                 }
             }
             (_, dst) => {