Fix a grammar mistake, and add a line about the two phases that the BB/SLP vectorizer...

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@179566 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/docs/Vectorizers.rst b/docs/Vectorizers.rst
index d5c286abd928f1a743730391afc027c2989938e5..d565c2122c9a0be711abf71411ec2c4f5fa28b9c 100644 (file)
--- a/docs/Vectorizers.rst
+++ b/docs/Vectorizers.rst
@@ -5,11 +5,11 @@ Auto-Vectorization in LLVM
 .. contents::
    :local:
 
-LLVM has two kind vectorizers: The :ref:`Loop Vectorizer <loop-vectorizer>`,
+LLVM has two vectorizers: The :ref:`Loop Vectorizer <loop-vectorizer>`,
 which operates on Loops, and the :ref:`SLP Vectorizer
 <slp-vectorizer>`, which optimizes straight-line code. These vectorizers
 focus on different optimization opportunities and use different techniques.
-The BB vectorizer merges multiple scalars that are found in the code into
+The SLP vectorizer merges multiple scalars that are found in the code into
 vectors while the Loop Vectorizer widens instructions in the original loop
 to operate on multiple consecutive loop iterations.
 
@@ -318,6 +318,8 @@ into vector operations.
     A[1] = a2*(a2 + b2)/b2 + 50*b2/a2;
   }
 
+The SLP-vectorizer has two phases, bottom-up, and top-down. The top-down vectorization
+phase is more aggressive, but takes more time to run.
 
 Usage
 ------
@@ -329,7 +331,7 @@ through clang using the command line flag:
 
    $ clang -fslp-vectorize file.c
 
-LLVM has a second phase basic block vectorization phase
+LLVM has a second basic block vectorization phase
 which is more compile-time intensive (The BB vectorizer). This optimization
 can be enabled through clang using the command line flag: