diff --git a/llvm/lib/Target/ARM/ARMISelLowering.cpp b/llvm/lib/Target/ARM/ARMISelLowering.cpp
index 9a247bb5a83d9..c283b0c77872e 100644
--- a/llvm/lib/Target/ARM/ARMISelLowering.cpp
+++ b/llvm/lib/Target/ARM/ARMISelLowering.cpp
@@ -20428,9 +20428,9 @@ void ARMTargetLowering::LowerAsmOperandForConstraint(SDValue Op,
           if (CVal >= -255 && CVal <= -1)
             break;
         } else {
-          // This must be a constant between -4095 and 4095. It is not clear
-          // what this constraint is intended for. Implemented for
-          // compatibility with GCC.
+          // This must be a constant between -4095 and 4095. This is suitable
+          // for use as the immediate offset field in LDR and STR instructions
+          // such as LDR r0,[r1,#offset].
           if (CVal >= -4095 && CVal <= 4095)
             break;
         }