[test] Fix use of 'sort -b' in SimpleLoopUnswitch on NetBSD

Add '-k 1' to 'sort -b' calls in SimpleLoopUnswitch tests, as required
for sort implementation on NetBSD.  The '-b' modifier is ineffective
if specified without any key.  Per the manpage:

  Note that the -b option has no effect unless key fields are specified.

Differential Revision: https://reviews.llvm.org/D55168

llvm-svn: 348097
diff --git a/llvm/test/Transforms/SimpleLoopUnswitch/exponential-nontrivial-unswitch-nested2.ll b/llvm/test/Transforms/SimpleLoopUnswitch/exponential-nontrivial-unswitch-nested2.ll
index c63f077..447d42b 100644
--- a/llvm/test/Transforms/SimpleLoopUnswitch/exponential-nontrivial-unswitch-nested2.ll
+++ b/llvm/test/Transforms/SimpleLoopUnswitch/exponential-nontrivial-unswitch-nested2.ll
@@ -23,7 +23,7 @@
 ; RUN: opt < %s -enable-nontrivial-unswitch -enable-unswitch-cost-multiplier=true \
 ; RUN:     -unswitch-num-initial-unscaled-candidates=3 -unswitch-siblings-toplevel-div=1 \
 ; RUN:     -passes='loop(unswitch),print<loops>' -disable-output 2>&1 | \
-; RUN:     sort -b | FileCheck %s --check-prefixes=LOOP-UNSCALE3-DIV1
+; RUN:     sort -b -k 1 | FileCheck %s --check-prefixes=LOOP-UNSCALE3-DIV1
 ;
 ; NB: sort -b is essential here and below, otherwise blanks might lead to different
 ; order depending on locale.
@@ -31,13 +31,13 @@
 ; RUN: opt < %s -enable-nontrivial-unswitch -enable-unswitch-cost-multiplier=true \
 ; RUN:     -unswitch-num-initial-unscaled-candidates=3 -unswitch-siblings-toplevel-div=2 \
 ; RUN:     -passes='loop(unswitch),print<loops>' -disable-output 2>&1 | \
-; RUN:     sort -b | FileCheck %s --check-prefixes=LOOP-UNSCALE3-DIV2
+; RUN:     sort -b -k 1 | FileCheck %s --check-prefixes=LOOP-UNSCALE3-DIV2
 ;
 ; With disabled cost-multiplier we get maximal possible amount of unswitches.
 ;
 ; RUN: opt < %s -enable-nontrivial-unswitch -enable-unswitch-cost-multiplier=false \
 ; RUN:     -passes='loop(unswitch),print<loops>' -disable-output 2>&1 | \
-; RUN:	   sort -b | FileCheck %s --check-prefixes=LOOP-MAX
+; RUN:	   sort -b -k 1 | FileCheck %s --check-prefixes=LOOP-MAX
 ;
 ; Single loop nest, not unswitched
 ; LOOP1:     Loop at depth 1 containing: