Review comments

Change-Id: Id1749b08b8e4ae360aa885458e9b45acbd017a39

Author: jrbyrnes

llvm/include/llvm/Analysis/CmpInstAnalysis.h

@@ -104,7 +104,7 @@ namespace llvm {
   /// Decompose an icmp into the form ((X & Mask) pred C) if possible.
   /// Unless \p AllowNonZeroC is true, C will always be 0. If \p
   /// DecomposeAnd is specified, then, for equality predicates, this will
-  /// decompose bitmasking (e.g. implemented via `and`).
+  /// decompose bitmasking via `and`.
   std::optional<DecomposedBitTest>
   decomposeBitTestICmp(Value *LHS, Value *RHS, CmpInst::Predicate Pred,
                        bool LookThroughTrunc = true, bool AllowNonZeroC = false,

llvm/lib/Analysis/CmpInstAnalysis.cpp

@@ -99,7 +99,6 @@ llvm::decomposeBitTestICmp(Value *LHS, Value *RHS, CmpInst::Predicate Pred,
   }
 
   DecomposedBitTest Result;
-
   switch (Pred) {
   default:
     llvm_unreachable("Unexpected predicate");
@@ -178,8 +177,9 @@ llvm::decomposeBitTestICmp(Value *LHS, Value *RHS, CmpInst::Predicate Pred,
     Result.X = X;
     Result.Mask = Result.Mask.zext(X->getType()->getScalarSizeInBits());
     Result.C = Result.C.zext(X->getType()->getScalarSizeInBits());
-  } else
+  } else {
     Result.X = LHS;
+  }
 
   return Result;
 }

llvm/lib/Transforms/InstCombine/InstCombineAndOrXor.cpp

@@ -877,7 +877,7 @@ static Value *foldSignedTruncationCheck(ICmpInst *ICmp0, ICmpInst *ICmp1,
     // Can it be decomposed into  icmp eq (X & Mask), 0  ?
     auto Res = llvm::decomposeBitTestICmp(
         ICmp->getOperand(0), ICmp->getOperand(1), Pred,
-        /*LookThroughTrunc=*/true, /*AllowNonZeroC=*/false,
+        /*LookThroughTrunc=*/false, /*AllowNonZeroC=*/false,
         /*DecomposeAnd=*/true);
     if (Res && Res->Pred == ICmpInst::ICMP_EQ) {
       X = Res->X;