diff options
Diffstat (limited to 'gcc/fortran/invoke.texi')
| -rw-r--r-- | gcc/fortran/invoke.texi | 24 |
1 files changed, 23 insertions, 1 deletions
diff --git a/gcc/fortran/invoke.texi b/gcc/fortran/invoke.texi index 51554a5ddcf..8c6aadd6153 100644 --- a/gcc/fortran/invoke.texi +++ b/gcc/fortran/invoke.texi @@ -152,7 +152,8 @@ by type. Explanations are in the following sections. @gccoptlist{ -fno-automatic -ff2c -fno-underscoring -fsecond-underscore @gol -fbounds-check -fmax-stack-var-size=@var{n} @gol --fpack-derived -frepack-arrays -fshort-enums} +-fpack-derived -frepack-arrays -fshort-enums -fexternal-blas +-fblas-matmul-limit=@var{n}} @end table @menu @@ -859,6 +860,27 @@ This option is provided for interoperability with C code that was compiled with the @command{-fshort-enums} option. It will make GNU Fortran choose the smallest @code{INTEGER} kind a given enumerator set will fit in, and give all its enumerators this kind. + +@cindex -fexternal-blas +@item -fexternal-blas +This option will make gfortran generate calls to BLAS functions for some +matrix operations like @code{MATMUL}, instead of using our own +algorithms, if the size of the matrices involved is larger than a given +limit (see @command{-fblas-matmul-limit}). This may be profitable if an +optimized vendor BLAS library is available. The BLAS library will have +to be specified at link time. + +@cindex -fblas-matmul-limit +@item -fblas-matmul-limit=@var{n} +Only significant when @command{-fexternal-blas} is in effect. +Matrix multiplication of matrices with size larger than (or equal to) @var{n} +will be performed by calls to BLAS functions, while others will be +handled by @command{gfortran} internal algorithms. If the matrices +involved are not square, the size comparison is performed using the +geometric mean of the dimensions of the argument and result matrices. + +The default value for @var{n} is 30. + @end table @xref{Code Gen Options,,Options for Code Generation Conventions, |
