Update default GPU architecture name to sm_20.

README.markdown

@@ -159,7 +159,7 @@ Specifies the temporary directory in which cl-cuda generates files such as `.cu`
 
 ### [Special Variable] \*nvcc-options\*
 
-Specifies additional command-line options to be passed to `nvcc` comand which cl-cuda calls internally. The default is `(list "-arch=sm_11")`.
+Specifies additional command-line options to be passed to `nvcc` comand which cl-cuda calls internally. The default is `(list "-arch=sm_20")`.
 
     (setf *nvcc-options* (list "-arch=sm_20 --verbose"))
 

src/api/nvcc.lisp

@@ -33,9 +33,7 @@
   (asdf:system-relative-pathname :cl-cuda #P"include"))
 
 (defvar *nvcc-options*
-  ;; compute capability 1.3 is needed for double floats, but 2.0 for
-  ;; good performance
-  (list "-arch=sm_11"))
+  (list "-arch=sm_20"))
 
 (defun get-nvcc-options (cu-path ptx-path)
   (let ((include-path (get-include-path)))