From a8eb70c9d70e2cdff032fdf80b304d70b002b120 Mon Sep 17 00:00:00 2001
From: joadnacer <joad.nacer@gmail.com>
Date: Sat, 21 Oct 2023 19:20:12 +0100
Subject: [PATCH]  compress: Improve RingBuffer usage

---
 lib/std/compress/zstandard.zig              | 4 +---
 lib/std/compress/zstandard/decode/block.zig | 8 +++-----
 2 files changed, 4 insertions(+), 8 deletions(-)

diff --git a/lib/std/compress/zstandard.zig b/lib/std/compress/zstandard.zig
index 1e8a0fc86f..9603fb32f9 100644
--- a/lib/std/compress/zstandard.zig
+++ b/lib/std/compress/zstandard.zig
@@ -219,9 +219,7 @@ pub fn DecompressStream(
             }
 
             const size = @min(self.buffer.len(), buffer.len);
-            for (0..size) |i| {
-                buffer[i] = self.buffer.read().?;
-            }
+            self.buffer.readFirstAssumeLength(buffer, size);
             if (self.state == .LastBlock and self.buffer.len() == 0) {
                 self.state = .NewFrame;
                 self.allocator.free(self.literal_fse_buffer);
diff --git a/lib/std/compress/zstandard/decode/block.zig b/lib/std/compress/zstandard/decode/block.zig
index bbf8492f04..4a035fb543 100644
--- a/lib/std/compress/zstandard/decode/block.zig
+++ b/lib/std/compress/zstandard/decode/block.zig
@@ -311,8 +311,8 @@ pub const DecodeState = struct {
         try self.decodeLiteralsRingBuffer(dest, sequence.literal_length);
         const copy_start = dest.write_index + dest.data.len - sequence.offset;
         const copy_slice = dest.sliceAt(copy_start, sequence.match_length);
-        for (copy_slice.first) |b| dest.writeAssumeCapacity(b);
-        for (copy_slice.second) |b| dest.writeAssumeCapacity(b);
+        dest.writeSliceForwardsAssumeCapacity(copy_slice.first);
+        dest.writeSliceForwardsAssumeCapacity(copy_slice.second);
         self.written_count += sequence.match_length;
     }
 
@@ -723,9 +723,7 @@ pub fn decodeBlockRingBuffer(
         },
         .rle => {
             if (src.len < 1) return error.MalformedRleBlock;
-            for (0..block_size) |_| {
-                dest.writeAssumeCapacity(src[0]);
-            }
+            dest.writeSliceAssumeCapacity(src[0..block_size]);
             consumed_count.* += 1;
             decode_state.written_count += block_size;
             return block_size;