Revert r282872 "CVP. Turn marking adds as no wrap on by default"

While not CVP's fault, this caused miscompiles (PR31181). Reverting
until those are resolved.

(This also reverts the follow-ups r288154 and r288161 which removed the
flag.)

llvm-svn: 296030

Author: zmodem

llvm/lib/Transforms/Scalar/CorrelatedValuePropagation.cpp

@@ -41,6 +41,8 @@ STATISTIC(NumSDivs,     "Number of sdiv converted to udiv");
 STATISTIC(NumAShrs,     "Number of ashr converted to lshr");
 STATISTIC(NumSRems,     "Number of srem converted to urem");
 
+static cl::opt<bool> DontProcessAdds("cvp-dont-process-adds", cl::init(true));
+
 namespace {
   class CorrelatedValuePropagation : public FunctionPass {
   public:
@@ -405,6 +407,9 @@ static bool processAShr(BinaryOperator *SDI, LazyValueInfo *LVI) {
 static bool processAdd(BinaryOperator *AddOp, LazyValueInfo *LVI) {
   typedef OverflowingBinaryOperator OBO;
 
+  if (DontProcessAdds)
+    return false;
+
   if (AddOp->getType()->isVectorTy() || hasLocalDefs(AddOp))
     return false;
 

llvm/test/Transforms/CorrelatedValuePropagation/add.ll

@@ -1,4 +1,4 @@
-; RUN: opt < %s -correlated-propagation -S | FileCheck %s
+; RUN: opt < %s -correlated-propagation -cvp-dont-process-adds=false -S | FileCheck %s
 
 ; CHECK-LABEL: @test0(
 define void @test0(i32 %a) {