fixup! Address review comments

Author: mshockwave

llvm/lib/CodeGen/InterleavedAccessPass.cpp

@@ -599,7 +599,7 @@ static std::pair<Value *, APInt> getMask(Value *WideMask, unsigned Factor,
         F && F == Factor) {
       Value *RefArg = nullptr;
       // Check if all the intrinsic arguments are the same, except those that
-      // are zeros, which we mark them as gaps in the gap mask.
+      // are zeros, which we mark as gaps in the gap mask.
       for (auto [Idx, Arg] : enumerate(IMI->args())) {
         if (auto *C = dyn_cast<Constant>(Arg); C && C->isZeroValue()) {
           GapMask.clearBit(Idx);
@@ -608,15 +608,16 @@ static std::pair<Value *, APInt> getMask(Value *WideMask, unsigned Factor,
 
         if (!RefArg)
           RefArg = Arg;
-
-        if (RefArg != Arg)
+        else if (RefArg != Arg)
           return {nullptr, GapMask};
       }
 
       // In a very rare occasion, all the intrinsic arguments might be zeros,
       // in which case we still want to return an all-zeros constant instead of
-      // nullptr, so we're not using RefArg here.
-      return {IMI->getArgOperand(0), GapMask};
+      // nullptr.
+      return {RefArg ? RefArg
+                     : Constant::getNullValue(IMI->getArgOperand(0)->getType()),
+              GapMask};
     }
   }
 

llvm/test/CodeGen/RISCV/rvv/fixed-vectors-interleaved-access.ll

@@ -205,8 +205,8 @@ define {<4 x i32>, <4 x i32>} @vpload_factor2_interleaved_mask_intrinsic(ptr %pt
   ret {<4 x i32>, <4 x i32>} %res1
 }
 
+; mask = %m, skip the last two fields.
 define {<2 x i32>, <2 x i32>} @vpload_factor4_interleaved_mask_intrinsic_skip_fields(ptr %ptr, <2 x i1> %m) {
-  ; mask = %m, skip the last two fields.
 ; CHECK-LABEL: vpload_factor4_interleaved_mask_intrinsic_skip_fields:
 ; CHECK:       # %bb.0:
 ; CHECK-NEXT:    li a1, 16