[CodeGen] Unify MBB reference format in both MIR and debug output

As part of the unification of the debug format and the MIR format, print
MBB references as '%bb.5'.

The MIR printer prints the IR name of a MBB only for block definitions.

* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#" << ([a-zA-Z0-9_]+)->getNumber\(\)/" << printMBBReference(*\1)/g'
* find . \( -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#" << ([a-zA-Z0-9_]+)\.getNumber\(\)/" << printMBBReference(\1)/g'
* find . \( -name "*.txt" -o -name "*.s" -o -name "*.mir" -o -name "*.cpp" -o -name "*.h" -o -name "*.ll" \) -type f -print0 | xargs -0 sed -i '' -E 's/BB#([0-9]+)/%bb.\1/g'
* grep -nr 'BB#' and fix

Differential Revision: https://reviews.llvm.org/D40422

llvm-svn: 319665
diff --git a/llvm/test/CodeGen/SPARC/vector-extract-elt.ll b/llvm/test/CodeGen/SPARC/vector-extract-elt.ll
index 702f063..47f39d5 100644
--- a/llvm/test/CodeGen/SPARC/vector-extract-elt.ll
+++ b/llvm/test/CodeGen/SPARC/vector-extract-elt.ll
@@ -5,7 +5,7 @@
 ; look-thru for extractelement then we we know that the add will yield a
 ; non-negative result.
 define i1 @test1(<4 x i16>* %in) {
-; CHECK-LABEL: ! BB#0:
+; CHECK-LABEL: ! %bb.0:
 ; CHECK-NEXT:        retl
 ; CHECK-NEXT:        sethi 0, %o0
   %vec2 = load <4 x i16>, <4 x i16>* %in, align 1