std: Standardize (input, output) param orderings

This functions swaps the order of arguments to a few functions that previously
took (output, input) parameters, but now take (input, output) parameters (in
that order).

The affected functions are:

* ptr::copy
* ptr::copy_nonoverlapping
* slice::bytes::copy_memory
* intrinsics::copy
* intrinsics::copy_nonoverlapping

Closes #22890
[breaking-change]

4 files changed, 9 insertions, 9 deletions

diff --git a/src/libstd/old_io/buffered.rs b/src/libstd/old_io/buffered.rs
index b8b7df75003..ad6cac62173 100644
--- a/src/libstd/old_io/buffered.rs
+++ b/src/libstd/old_io/buffered.rs
@@ -118,7 +118,7 @@ impl<R: Reader> Reader for BufferedReader<R> {
         let nread = {
             let available = try!(self.fill_buf());
             let nread = cmp::min(available.len(), buf.len());
-            slice::bytes::copy_memory(buf, &available[..nread]);
+            slice::bytes::copy_memory(&available[..nread], buf);
             nread
         };
         self.pos += nread;
@@ -225,7 +225,7 @@ impl<W: Writer> Writer for BufferedWriter<W> {
             self.inner.as_mut().unwrap().write_all(buf)
         } else {
             let dst = &mut self.buf[self.pos..];
-            slice::bytes::copy_memory(dst, buf);
+            slice::bytes::copy_memory(buf, dst);
             self.pos += buf.len();
             Ok(())
         }
diff --git a/src/libstd/old_io/comm_adapters.rs b/src/libstd/old_io/comm_adapters.rs
index 35bc58fecd2..5ebf931e95c 100644
--- a/src/libstd/old_io/comm_adapters.rs
+++ b/src/libstd/old_io/comm_adapters.rs
@@ -91,7 +91,7 @@ impl Reader for ChanReader {
                 Some(src) => {
                     let dst = &mut buf[num_read..];
                     let count = cmp::min(src.len(), dst.len());
-                    bytes::copy_memory(dst, &src[..count]);
+                    bytes::copy_memory(&src[..count], dst);
                     count
                 },
                 None => 0,
diff --git a/src/libstd/old_io/extensions.rs b/src/libstd/old_io/extensions.rs
index 441f0a7536e..0e5dd3aa4aa 100644
--- a/src/libstd/old_io/extensions.rs
+++ b/src/libstd/old_io/extensions.rs
@@ -171,7 +171,7 @@ pub fn u64_from_be_bytes(data: &[u8], start: usize, size: usize) -> u64 {
     unsafe {
         let ptr = data.as_ptr().offset(start as isize);
         let out = buf.as_mut_ptr();
-        copy_nonoverlapping(out.offset((8 - size) as isize), ptr, size);
+        copy_nonoverlapping(ptr, out.offset((8 - size) as isize), size);
         (*(out as *const u64)).to_be()
     }
 }
diff --git a/src/libstd/old_io/mem.rs b/src/libstd/old_io/mem.rs
index 5f20c383bb7..64803191d4f 100644
--- a/src/libstd/old_io/mem.rs
+++ b/src/libstd/old_io/mem.rs
@@ -168,7 +168,7 @@ impl Reader for MemReader {
             let input = &self.buf[self.pos.. self.pos + write_len];
             let output = &mut buf[..write_len];
             assert_eq!(input.len(), output.len());
-            slice::bytes::copy_memory(output, input);
+            slice::bytes::copy_memory(input, output);
         }
         self.pos += write_len;
         assert!(self.pos <= self.buf.len());
@@ -212,7 +212,7 @@ impl<'a> Reader for &'a [u8] {
         {
             let input = &self[..write_len];
             let output = &mut buf[.. write_len];
-            slice::bytes::copy_memory(output, input);
+            slice::bytes::copy_memory(input, output);
         }
 
         *self = &self[write_len..];
@@ -287,13 +287,13 @@ impl<'a> Writer for BufWriter<'a> {
         let src_len = src.len();
 
         if dst_len >= src_len {
-            slice::bytes::copy_memory(dst, src);
+            slice::bytes::copy_memory(src, dst);
 
             self.pos += src_len;
 
             Ok(())
         } else {
-            slice::bytes::copy_memory(dst, &src[..dst_len]);
+            slice::bytes::copy_memory(&src[..dst_len], dst);
 
             self.pos += dst_len;
 
@@ -360,7 +360,7 @@ impl<'a> Reader for BufReader<'a> {
             let input = &self.buf[self.pos.. self.pos + write_len];
             let output = &mut buf[..write_len];
             assert_eq!(input.len(), output.len());
-            slice::bytes::copy_memory(output, input);
+            slice::bytes::copy_memory(input, output);
         }
         self.pos += write_len;
         assert!(self.pos <= self.buf.len());