SelectionDAG: add a -filter-view-dags option to llc
    
This option takes the name of the basic block you want to visualize
with -view-*-dags

Differential Revision: http://reviews.llvm.org/D6948

llvm-svn: 225953
diff --git a/llvm/docs/CodeGenerator.rst b/llvm/docs/CodeGenerator.rst
index b0a1059..7e5b6eb 100644
--- a/llvm/docs/CodeGenerator.rst
+++ b/llvm/docs/CodeGenerator.rst
@@ -464,7 +464,7 @@
   mov %EAX, %EDX
   sar %EDX, 31
   idiv %ECX
-  ret 
+  ret
 
 This approach is extremely general (if it can handle the X86 architecture, it
 can handle anything!) and allows all of the target specific knowledge about the
@@ -848,6 +848,10 @@
 bundled into a single scheduling-unit node, and with immediate operands and
 other nodes that aren't relevant for scheduling omitted.
 
+The option ``-filter-view-dags`` allows to select the name of the basic block
+that you are interested to visualize and filters all the previous
+``view-*-dags`` options.
+
 .. _Build initial DAG:
 
 Initial SelectionDAG Construction