From: Sanjay Patel Date: Thu, 10 Jan 2019 17:02:55 +0000 (+0000) Subject: [Docs] fix typo, adjust text order X-Git-Url: https://granicus.if.org/sourcecode?a=commitdiff_plain;h=337d71157f684c38bc2c9b1bb3e63837a9319cd8;p=llvm [Docs] fix typo, adjust text order git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@350846 91177308-0d34-0410-b5e6-96231b3b80d8 --- diff --git a/docs/Vectorizers.rst b/docs/Vectorizers.rst index 4a015800741..8ac7ae0847d 100644 --- a/docs/Vectorizers.rst +++ b/docs/Vectorizers.rst @@ -311,7 +311,7 @@ ignored (as other compilers do) are still being left un-vectorized. Vectorization of function calls ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ -The Loop Vectorize can vectorize intrinsic math functions. +The Loop Vectorizer can vectorize intrinsic math functions. See the table below for a list of these functions. +-----+-----+---------+ @@ -328,6 +328,11 @@ See the table below for a list of these functions. | | | fmuladd | +-----+-----+---------+ +Note that the optimizer may not be able to vectorize math library functions +that correspond to these intrinsics if the library calls access external state +such as "errno". To allow better optimization of C/C++ math library functions, +use "-fno-math-errno". + The loop vectorizer knows about special instructions on the target and will vectorize a loop containing a function call that maps to the instructions. For example, the loop below will be vectorized on Intel x86 if the SSE4.1 roundps @@ -340,10 +345,6 @@ instruction is available. f[i] = floorf(f[i]); } -Note that the optimizer may not be able to vectorize math library functions -that access external state such as "errno". To allow better optimization of -C/C++ math library functions, use "-fno-math-errno". - Partial unrolling during vectorization ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^