Adding -verify-machineinstrs option to PowerPC tests

Currently we have a number of tests that fail with -verify-machineinstrs.
To detect this cases earlier we add the option to the testcases with the
exception of tests that will currently fail with this option. PR 27456 keeps
track of this failures.

No code review, as discussed with Hal Finkel.

llvm-svn: 277624
diff --git a/llvm/test/CodeGen/PowerPC/swaps-le-5.ll b/llvm/test/CodeGen/PowerPC/swaps-le-5.ll
index 3e13bd1..3233972 100644
--- a/llvm/test/CodeGen/PowerPC/swaps-le-5.ll
+++ b/llvm/test/CodeGen/PowerPC/swaps-le-5.ll
@@ -1,4 +1,4 @@
-; RUN: llc -mcpu=pwr8 -mtriple=powerpc64le-unknown-linux-gnu -O3 < %s | FileCheck %s
+; RUN: llc -verify-machineinstrs -mcpu=pwr8 -mtriple=powerpc64le-unknown-linux-gnu -O3 < %s | FileCheck %s
 
 ; These tests verify that VSX swap optimization works for various
 ; manipulations of <2 x double> vectors.