performance: committed wrong version of buf_set_buf optimization

[fw/openocd] / src / helper / binarybuffer.c

diff --git a/src/helper/binarybuffer.c b/src/helper/binarybuffer.c
index e789e6ff1b52a1c0282c124483f163dd62dd8d83..5732689c01e95fd8ff1033e45427a5bc0417d821 100644 (file)
--- a/src/helper/binarybuffer.c
+++ b/src/helper/binarybuffer.c
@@ -133,26 +133,40 @@ void* buf_set_buf(const void *_src, unsigned src_start,
 {
        const uint8_t *src = _src;
        uint8_t *dst = _dst;
-       unsigned  sb,db,sq,dq;
+       unsigned  i,sb,db,sq,dq, lb,lq;
 
        sb = src_start / 8;
        db = dst_start / 8;
        sq = src_start % 8;
        dq = dst_start % 8;
+       lb = len / 8;
+       lq = len % 8;
 
-       for (unsigned i = 0; i < len; i++)
+       src += sb;
+       dst += db;
+
+       /* check if both buffers are on byte boundary and
+        * len is a multiple of 8bit so we can simple copy
+        * the buffer */
+       if ( (sq == 0) && (dq == 0) &&  (lq == 0) )
+       {
+               for (i = 0; i < lb; i++)
+                       *dst++ = *src++;
+               return (uint8_t*)_dst;
+       }
+
+       /* fallback to slow bit copy */
+       for (i = 0; i < len; i++)
        {
                if (((*src >> (sq&7)) & 1) == 1)
                        *dst |= 1 << (dq&7);
                else
                        *dst &= ~(1 << (dq&7));
-
                if ( sq++ == 7 )
                {
                        sq = 0;
                        src++;
                }
-
                if ( dq++ == 7 )
                {
                        dq = 0;