Another little optimization.

Removes one branch from the hot path, deduplicates one function call in the cold
path by effectively falling through, and makes it more obvious what the code is
actually trying to do.

svn path=/trunk/; revision=51013

1 files changed, 11 insertions, 18 deletions

diff --git a/epan/wmem/wmem_allocator_block.c b/epan/wmem/wmem_allocator_block.c
index f343af9fa3..7cd34cc153 100644
--- a/epan/wmem/wmem_allocator_block.c
+++ b/epan/wmem/wmem_allocator_block.c
@@ -540,25 +540,18 @@ wmem_block_split_free_chunk(wmem_block_allocator_t *allocator,
 
     aligned_size = WMEM_ALIGN_SIZE(size) + sizeof(wmem_block_chunk_t);
 
-    if (aligned_size > WMEM_CHUNK_DATA_LEN(chunk)) {
-        /* In this case we don't have enough space to really split it, so we
-         * don't. Just remove it from its free list and return. */
-        wmem_block_unfree(allocator, chunk);
-        return;
-    }
-    /* otherwise, we have room to split it, though the remaining free chunk
-     * may still not be usefully large */
-
-    if (chunk->len < aligned_size +
-                    (sizeof(wmem_block_chunk_t) + sizeof(wmem_block_free_t))) {
-        /* If the available space is not enought to store the first part
-         * (header + size) AND the second part (header + free_header) then
-         * simply remove the current chunk from the free list. Do it now before
-         * we start messing with header values and confuse things.
-         *
-         * If we do have room, we reuse the free_header from our current chunk
-         * later on, so we don't have to do a full remove/insert. */
+    if (WMEM_CHUNK_DATA_LEN(chunk) < aligned_size + sizeof(wmem_block_free_t)) {
+        /* If the available space is not enought to store all of
+         * (hdr + requested size + alignment padding + hdr + free-header) then
+         * remove the current chunk from the free list. If the chunk does have
+         * space we reuse its free-header later, so we don't have to do a full
+         * remove/insert. */
         wmem_block_unfree(allocator, chunk);
+        if (WMEM_CHUNK_DATA_LEN(chunk) < aligned_size) {
+            /* If it doesn't even have room for just the chunk header then we
+             * can't split it at all, so just return. */
+            return;
+        }
     }
 
     /* preserve a few values from chunk that we'll need to manipulate */