[SPARC]: recognize '.' as the start of an assembler expression.

llvm-svn: 245232
diff --git a/llvm/test/MC/Sparc/sparc-assembly-exprs.s b/llvm/test/MC/Sparc/sparc-assembly-exprs.s
index 7fdc5a5..b6f8e09 100644
--- a/llvm/test/MC/Sparc/sparc-assembly-exprs.s
+++ b/llvm/test/MC/Sparc/sparc-assembly-exprs.s
@@ -4,3 +4,10 @@
         mov      (0x400|9), %o1
         ! CHECK: mov 60, %o2    ! encoding: [0x94,0x10,0x20,0x3c]
         mov      (12+3<<2), %o2
+
+! "." is exactly like a temporary symbol equated to the current line.
+! RUN: llvm-mc %s -arch=sparc | FileCheck %s --check-prefix=DOTEXPR
+
+        ! DOTEXPR: .Ltmp0
+        ! DOTEXPR-NEXT: ba .Ltmp0+8
+        b . + 8