[InstCombine] Make combines on `llvm.ptrmask` fail loudly if we have vec types; NFC

[goldstein.w.n]

Summary

Currently vec types are unsupported by llvm.ptrmask. Should this
change its probably better to fail loudly rather hope the code ends up
working properly for vec types.

[goldstein.w.n]

This has been ported to github PR.

llvm/lib/Transforms/InstCombine/InstCombineCalls.cpp

if (!isPowerOf2_32(BitWidth))
       break;
     APInt Op2Demanded = APInt::getLowBitsSet(BitWidth, Log2_32_Ceil(BitWidth));
     KnownBits Op2Known(BitWidth);
     if (SimplifyDemandedBits(II, 2, Op2Demanded, Op2Known))
       return &CI;
     break;
   }
   case Intrinsic::ptrmask: {
+    Value *Op0 = II->getArgOperand(0);
+    Value *Op1 = II->getArgOperand(1);
+    // Fail loudly in case this is ever changed.
+    // TODO: If vector types are supported the merging of (ptrmask (ptrmask))
+    // need to ensure we don't merge a vectype with non-vec type.
+    assert(!Op0->getType()->isVectorTy() && !Op1->getType()->isVectorTy() &&
+           "These combines where written at a time when ptrmask did not "
+           "support vector types and may not work for vectors");
+
     Value *InnerPtr, *InnerMask;
     if (match(II->getArgOperand(0),
               m_OneUse(m_Intrinsic<Intrinsic::ptrmask>(m_Value(InnerPtr),
                                                        m_Value(InnerMask))))) {
       if (II->getArgOperand(1)->getType() == InnerMask->getType()) {
         Value *NewMask = Builder.CreateAnd(II->getArgOperand(1), InnerMask);
         return replaceInstUsesWith(
             *II,