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| author | Paul Redmond <paul.redmond@intel.com> | 2013-05-30 17:22:46 +0000 |
|---|---|---|
| committer | Paul Redmond <paul.redmond@intel.com> | 2013-05-30 17:22:46 +0000 |
| commit | f95ac8a4740d479b38516b9f8ff8be9d89c4952f (patch) | |
| tree | ace36023efa1e64aea0ff3c479fd408053a01f3d /docs | |
| parent | 977de2d86906b66bf5fd3e891221570a5a41050e (diff) | |
| download | llvm-f95ac8a4740d479b38516b9f8ff8be9d89c4952f.tar.gz llvm-f95ac8a4740d479b38516b9f8ff8be9d89c4952f.tar.bz2 llvm-f95ac8a4740d479b38516b9f8ff8be9d89c4952f.tar.xz | |
Revise llvm.vectorizer.width documentation
- clarify that vectorizer.width only applies if the vectorizer decides to
vectorize.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@182938 91177308-0d34-0410-b5e6-96231b3b80d8
Diffstat (limited to 'docs')
| -rw-r--r-- | docs/LangRef.rst | 6 |
1 files changed, 4 insertions, 2 deletions
diff --git a/docs/LangRef.rst b/docs/LangRef.rst index 72648edbcb..e07d8fe8db 100644 --- a/docs/LangRef.rst +++ b/docs/LangRef.rst @@ -2680,8 +2680,10 @@ determined automatically. '``llvm.vectorizer.width``' Metadata ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ -This metadata forces the loop vectorizer to widen scalar values to a vector -width of ``N`` rather than computing the width using a cost model. +This metadata sets the target width of the vectorizer to ``N``. Without +this metadata, the vectorizer will choose a width automatically. +Regardless of this metadata, the vectorizer will only vectorize loops if +it believes it is valid to do so. The first operand is the string ``llvm.vectorizer.width`` and the second operand is an integer specifying the width. For example: |