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| author | Nadav Rotem <nrotem@apple.com> | 2013-04-08 21:34:49 +0000 |
|---|---|---|
| committer | Nadav Rotem <nrotem@apple.com> | 2013-04-08 21:34:49 +0000 |
| commit | df4381b578b291e1d1044f29ce4720b16ad0b12c (patch) | |
| tree | 7d086a9bf64b2d0132de40128a385140a9905a5a /docs | |
| parent | 335f1d46d82a4d6b5a7317ccc73178a47b62fc25 (diff) | |
| download | llvm-df4381b578b291e1d1044f29ce4720b16ad0b12c.tar.gz llvm-df4381b578b291e1d1044f29ce4720b16ad0b12c.tar.bz2 llvm-df4381b578b291e1d1044f29ce4720b16ad0b12c.tar.xz | |
Update the docs about the fact that the loop vectorizer is enabled by default for -O3.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179060 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'docs')
| -rw-r--r-- | docs/Vectorizers.rst | 13 |
1 files changed, 4 insertions, 9 deletions
diff --git a/docs/Vectorizers.rst b/docs/Vectorizers.rst index e2d3667bc1..2c5604496b 100644 --- a/docs/Vectorizers.rst +++ b/docs/Vectorizers.rst @@ -21,19 +21,14 @@ The Loop Vectorizer Usage ----- -LLVM's Loop Vectorizer is now available and will be useful for many people. -It is not enabled by default, but can be enabled through clang using the -command line flag: +LLVM's Loop Vectorizer is now enabled by default for -O3. +The vectorizer can be disabled using the command line: .. code-block:: console - $ clang -fvectorize -O3 file.c + $ clang ... -fno-vectorize file.c -If the ``-fvectorize`` flag is used then the loop vectorizer will be enabled -when running with ``-O3``, ``-O2``. When ``-Os`` is used, the loop vectorizer -will only vectorize loops that do not require a major increase in code size. - -We plan to enable the Loop Vectorizer by default as part of the LLVM 3.3 release. +At this point the loop vectorizer is only enabled for -O3, and will not work for -O2 or -Os. Command line flags ^^^^^^^^^^^^^^^^^^ |