diff options
| author | Jan Lindström <jan.lindstrom@mariadb.com> | 2015-05-11 14:29:14 +0300 |
|---|---|---|
| committer | Jan Lindström <jan.lindstrom@mariadb.com> | 2015-05-11 14:31:42 +0300 |
| commit | 58e8db2eb398a812e2894d28db4173a4f67fea06 (patch) | |
| tree | d46891529e0cd7db1eb36acae5d099035d95c7b0 /storage | |
| parent | 6e4920164426543082d02cde4c60bd29cbd54f99 (diff) | |
| download | mariadb-git-58e8db2eb398a812e2894d28db4173a4f67fea06.tar.gz | |
MDEV-7942: InnoDB: abuse of UNIV_LIKELY()/UNIV_UNLIKELY()
UNIV_LIKELY()/UNIV_UNLIKELY() hints are supposed to improve branch prediction.
Currently, they're expected to work only if cond evaluates to TRUE or FALSE.
However there're a few conditions that may evaluate to different values, e.g.:
page/page0zip.cc: if (UNIV_LIKELY(c_stream->avail_in)) {
page/page0zip.cc: if (UNIV_LIKELY(c_stream->avail_in)) {
dict/dict0mem.cc: if (UNIV_LIKELY(i) && UNIV_UNLIKELY(!table->col_names)) {
Fixed these conditions so that they evaluate TRUE/FALSE.
Diffstat (limited to 'storage')
| -rw-r--r-- | storage/innobase/dict/dict0mem.cc | 2 | ||||
| -rw-r--r-- | storage/innobase/page/page0zip.cc | 4 | ||||
| -rw-r--r-- | storage/xtradb/dict/dict0mem.cc | 2 | ||||
| -rw-r--r-- | storage/xtradb/page/page0zip.cc | 4 |
4 files changed, 6 insertions, 6 deletions
diff --git a/storage/innobase/dict/dict0mem.cc b/storage/innobase/dict/dict0mem.cc index f0ea15d9513..6684b75c9f2 100644 --- a/storage/innobase/dict/dict0mem.cc +++ b/storage/innobase/dict/dict0mem.cc @@ -285,7 +285,7 @@ dict_mem_table_add_col( if (UNIV_UNLIKELY(table->n_def == table->n_cols)) { heap = table->heap; } - if (UNIV_LIKELY(i) && UNIV_UNLIKELY(!table->col_names)) { + if (UNIV_LIKELY(i != 0) && UNIV_UNLIKELY(table->col_names == NULL)) { /* All preceding column names are empty. */ char* s = static_cast<char*>( mem_heap_zalloc(heap, table->n_def)); diff --git a/storage/innobase/page/page0zip.cc b/storage/innobase/page/page0zip.cc index 93f63ab15ac..f518746e21d 100644 --- a/storage/innobase/page/page0zip.cc +++ b/storage/innobase/page/page0zip.cc @@ -923,7 +923,7 @@ page_zip_compress_sec( rec - REC_N_NEW_EXTRA_BYTES - c_stream->next_in); - if (UNIV_LIKELY(c_stream->avail_in)) { + if (UNIV_LIKELY(c_stream->avail_in != 0)) { UNIV_MEM_ASSERT_RW(c_stream->next_in, c_stream->avail_in); err = deflate(c_stream, Z_NO_FLUSH); @@ -1018,7 +1018,7 @@ page_zip_compress_clust_ext( c_stream->avail_in = static_cast<uInt>( src - c_stream->next_in); - if (UNIV_LIKELY(c_stream->avail_in)) { + if (UNIV_LIKELY(c_stream->avail_in != 0)) { err = deflate(c_stream, Z_NO_FLUSH); if (UNIV_UNLIKELY(err != Z_OK)) { diff --git a/storage/xtradb/dict/dict0mem.cc b/storage/xtradb/dict/dict0mem.cc index 997e630dd15..3c23b55374c 100644 --- a/storage/xtradb/dict/dict0mem.cc +++ b/storage/xtradb/dict/dict0mem.cc @@ -301,7 +301,7 @@ dict_mem_table_add_col( if (UNIV_UNLIKELY(table->n_def == table->n_cols)) { heap = table->heap; } - if (UNIV_LIKELY(i) && UNIV_UNLIKELY(!table->col_names)) { + if (UNIV_LIKELY(i != 0) && UNIV_UNLIKELY(table->col_names == NULL)) { /* All preceding column names are empty. */ char* s = static_cast<char*>( mem_heap_zalloc(heap, table->n_def)); diff --git a/storage/xtradb/page/page0zip.cc b/storage/xtradb/page/page0zip.cc index 9ad39147d0d..86c33ab5efb 100644 --- a/storage/xtradb/page/page0zip.cc +++ b/storage/xtradb/page/page0zip.cc @@ -912,7 +912,7 @@ page_zip_compress_sec( rec - REC_N_NEW_EXTRA_BYTES - c_stream->next_in); - if (UNIV_LIKELY(c_stream->avail_in)) { + if (UNIV_LIKELY(c_stream->avail_in != 0)) { UNIV_MEM_ASSERT_RW(c_stream->next_in, c_stream->avail_in); err = deflate(c_stream, Z_NO_FLUSH); @@ -1007,7 +1007,7 @@ page_zip_compress_clust_ext( c_stream->avail_in = static_cast<uInt>( src - c_stream->next_in); - if (UNIV_LIKELY(c_stream->avail_in)) { + if (UNIV_LIKELY(c_stream->avail_in != 0)) { err = deflate(c_stream, Z_NO_FLUSH); if (UNIV_UNLIKELY(err != Z_OK)) { |