[llvm] [ADT] Make use of subsetOf and anyCommon methods of BitVector (NFC) (PR #170876)

[Anatoly Trosinenko via llvm-commits]

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@@ -274,11 +274,9 @@ static Error randomizeMCOperand(const LLVMState &State,
     break;
   case MCOI::OperandType::OPERAND_REGISTER: {
     assert(Op.isReg());
-    auto AllowedRegs = Op.getRegisterAliasing().sourceBits();
+    const BitVector &AllowedRegs = Op.getRegisterAliasing().sourceBits();
     assert(AllowedRegs.size() == ForbiddenRegs.size());
-    for (auto I : ForbiddenRegs.set_bits())
-      AllowedRegs.reset(I);
-    if (!AllowedRegs.any())
+    if (AllowedRegs.subsetOf(ForbiddenRegs))
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atrosinenko wrote:

Reverted this particular change in b0f5356335f9eba40a1977654b6038740b3a332c.

https://github.com/llvm/llvm-project/pull/170876