diff --git a/llvm/include/llvm/CodeGen/TargetLowering.h b/llvm/include/llvm/CodeGen/TargetLowering.h
--- a/llvm/include/llvm/CodeGen/TargetLowering.h
+++ b/llvm/include/llvm/CodeGen/TargetLowering.h
@@ -2116,13 +2116,10 @@
     PrefFunctionAlignment = llvm::Align(1ULL << LogAlign);
   }
 
-  /// Set the target's preferred loop alignment. Default alignment is zero, it
-  /// means the target does not care about loop alignment.  The alignment is
-  /// specified in log2(bytes). The target may also override
-  /// getPrefLoopAlignment to provide per-loop values.
-  void setPrefLoopLogAlignment(unsigned LogAlign) {
-    PrefLoopAlignment = llvm::Align(1ULL << LogAlign);
-  }
+  /// Set the target's preferred loop alignment. Default alignment is one, it
+  /// means the target does not care about loop alignment. The target may also
+  /// override getPrefLoopAlignment to provide per-loop values.
+  void setPrefLoopAlignment(llvm::Align Align) { PrefLoopAlignment = Align; }
 
   /// Set the minimum stack alignment of an argument.
   void setMinStackArgumentAlignment(unsigned Align) {
diff --git a/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp b/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
--- a/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
+++ b/llvm/lib/Target/AArch64/AArch64ISelLowering.cpp
@@ -643,7 +643,7 @@
   setMinFunctionAlignment(llvm::Align(4));
   // Set preferred alignments.
   setPrefFunctionLogAlignment(STI.getPrefFunctionLogAlignment());
-  setPrefLoopLogAlignment(STI.getPrefLoopLogAlignment());
+  setPrefLoopAlignment(llvm::Align(1ULL << STI.getPrefLoopLogAlignment()));
 
   // Only change the limit for entries in a jump table if specified by
   // the sub target, but not at the command line.
diff --git a/llvm/lib/Target/ARM/ARMISelLowering.cpp b/llvm/lib/Target/ARM/ARMISelLowering.cpp
--- a/llvm/lib/Target/ARM/ARMISelLowering.cpp
+++ b/llvm/lib/Target/ARM/ARMISelLowering.cpp
@@ -1419,7 +1419,8 @@
   // Prefer likely predicted branches to selects on out-of-order cores.
   PredictableSelectIsExpensive = Subtarget->getSchedModel().isOutOfOrder();
 
-  setPrefLoopLogAlignment(Subtarget->getPrefLoopLogAlignment());
+  setPrefLoopAlignment(
+      llvm::Align(1UL << Subtarget->getPrefLoopLogAlignment()));
 
   setMinFunctionAlignment(Subtarget->isThumb() ? llvm::Align(2)
                                                : llvm::Align(4));
diff --git a/llvm/lib/Target/Hexagon/HexagonISelLowering.cpp b/llvm/lib/Target/Hexagon/HexagonISelLowering.cpp
--- a/llvm/lib/Target/Hexagon/HexagonISelLowering.cpp
+++ b/llvm/lib/Target/Hexagon/HexagonISelLowering.cpp
@@ -1235,7 +1235,7 @@
       Subtarget(ST) {
   auto &HRI = *Subtarget.getRegisterInfo();
 
-  setPrefLoopLogAlignment(4);
+  setPrefLoopAlignment(llvm::Align(16));
   setPrefFunctionLogAlignment(4);
   setMinFunctionAlignment(llvm::Align(4));
   setStackPointerRegisterToSaveRestore(HRI.getStackRegister());
diff --git a/llvm/lib/Target/PowerPC/PPCISelLowering.cpp b/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
--- a/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
+++ b/llvm/lib/Target/PowerPC/PPCISelLowering.cpp
@@ -1200,7 +1200,7 @@
   case PPC::DIR_PWR8:
   case PPC::DIR_PWR9:
     setPrefFunctionLogAlignment(4);
-    setPrefLoopLogAlignment(4);
+    setPrefLoopAlignment(llvm::Align(16));
     break;
   }
 
diff --git a/llvm/lib/Target/X86/X86ISelLowering.cpp b/llvm/lib/Target/X86/X86ISelLowering.cpp
--- a/llvm/lib/Target/X86/X86ISelLowering.cpp
+++ b/llvm/lib/Target/X86/X86ISelLowering.cpp
@@ -73,9 +73,10 @@
 
 static cl::opt<int> ExperimentalPrefLoopAlignment(
     "x86-experimental-pref-loop-alignment", cl::init(4),
-    cl::desc("Sets the preferable loop alignment for experiments "
-             "(the last x86-experimental-pref-loop-alignment bits"
-             " of the loop header PC will be 0)."),
+    cl::desc(
+        "Sets the preferable loop alignment for experiments (as log2 bytes)"
+        "(the last x86-experimental-pref-loop-alignment bits"
+        " of the loop header PC will be 0)."),
     cl::Hidden);
 
 // Added in 10.0.
@@ -1892,7 +1893,7 @@
   MaxLoadsPerMemcmpOptSize = 2;
 
   // Set loop alignment to 2^ExperimentalPrefLoopAlignment bytes (default: 2^4).
-  setPrefLoopLogAlignment(ExperimentalPrefLoopAlignment);
+  setPrefLoopAlignment(llvm::Align(1UL << ExperimentalPrefLoopAlignment));
 
   // An out-of-order CPU can speculatively execute past a predictable branch,
   // but a conditional move could be stalled by an expensive earlier operation.