collectBitParts - use const references. NFCI.

Fixes clang-tidy warnings first noticed on D87452.

diff --git a/llvm/lib/Transforms/Utils/Local.cpp b/llvm/lib/Transforms/Utils/Local.cpp
index 4134945..0b848fe 100644 (file)
--- a/llvm/lib/Transforms/Utils/Local.cpp
+++ b/llvm/lib/Transforms/Utils/Local.cpp
@@ -2795,10 +2795,10 @@ collectBitParts(Value *V, bool MatchBSwaps, bool MatchBitReversals,
   if (Instruction *I = dyn_cast<Instruction>(V)) {
     // If this is an or instruction, it may be an inner node of the bswap.
     if (I->getOpcode() == Instruction::Or) {
-      auto &A = collectBitParts(I->getOperand(0), MatchBSwaps,
-                                MatchBitReversals, BPS, Depth + 1);
-      auto &B = collectBitParts(I->getOperand(1), MatchBSwaps,
-                                MatchBitReversals, BPS, Depth + 1);
+      const auto &A = collectBitParts(I->getOperand(0), MatchBSwaps,
+                                      MatchBitReversals, BPS, Depth + 1);
+      const auto &B = collectBitParts(I->getOperand(1), MatchBSwaps,
+                                      MatchBitReversals, BPS, Depth + 1);
       if (!A || !B)
         return Result;
 
@@ -2830,8 +2830,8 @@ collectBitParts(Value *V, bool MatchBSwaps, bool MatchBitReversals,
       if (BitShift > BitWidth)
         return Result;
 
-      auto &Res = collectBitParts(I->getOperand(0), MatchBSwaps,
-                                  MatchBitReversals, BPS, Depth + 1);
+      const auto &Res = collectBitParts(I->getOperand(0), MatchBSwaps,
+                                        MatchBitReversals, BPS, Depth + 1);
       if (!Res)
         return Result;
       Result = Res;
@@ -2862,8 +2862,8 @@ collectBitParts(Value *V, bool MatchBSwaps, bool MatchBitReversals,
       if (!MatchBitReversals && NumMaskedBits % 8 != 0)
         return Result;
 
-      auto &Res = collectBitParts(I->getOperand(0), MatchBSwaps,
-                                  MatchBitReversals, BPS, Depth + 1);
+      const auto &Res = collectBitParts(I->getOperand(0), MatchBSwaps,
+                                        MatchBitReversals, BPS, Depth + 1);
       if (!Res)
         return Result;
       Result = Res;
@@ -2877,8 +2877,8 @@ collectBitParts(Value *V, bool MatchBSwaps, bool MatchBitReversals,
 
     // If this is a zext instruction zero extend the result.
     if (I->getOpcode() == Instruction::ZExt) {
-      auto &Res = collectBitParts(I->getOperand(0), MatchBSwaps,
-                                  MatchBitReversals, BPS, Depth + 1);
+      const auto &Res = collectBitParts(I->getOperand(0), MatchBSwaps,
+                                        MatchBitReversals, BPS, Depth + 1);
       if (!Res)
         return Result;