Disabling the transformation introduced in r315888

The commit at https://reviews.llvm.org/rL315888 is causing some failures
with internal testing. Disabling this code until we can resolve the issues.

llvm-svn: 316199

llvm/lib/Target/PowerPC/PPCMIPeephole.cpp

@@ -43,12 +43,12 @@ STATISTIC(NumOptADDLIs, "Number of optimized ADD instruction fed by LI");
 static cl::opt<bool>
     EnableSExtElimination("ppc-eliminate-signext",
                           cl::desc("enable elimination of sign-extensions"),
-                          cl::init(true), cl::Hidden);
+                          cl::init(false), cl::Hidden);
 
 static cl::opt<bool>
     EnableZExtElimination("ppc-eliminate-zeroext",
                           cl::desc("enable elimination of zero-extensions"),
-                          cl::init(true), cl::Hidden);
+                          cl::init(false), cl::Hidden);
 
 namespace llvm {
   void initializePPCMIPeepholePass(PassRegistry&);

llvm/test/CodeGen/PowerPC/ppc-ctr-dead-code.ll

@@ -31,7 +31,7 @@ cleanup:                                          ; preds = %for.body, %for.cond
 ; CHECK-LABEL: limit_loop
 ; CHECK: mtctr
 ; CHECK-NOT: addi {{[0-9]+}}, {{[0-9]+}}, 1
-; CHECK: bdzlr
+; CHECK: bdnz
 ; CHECK: blr
 }