[llvm] [SandboxIR][Region] Implement an auxiliary vector in Region (PR #126376)

[Simon Pilgrim via llvm-commits]

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@@ -57,6 +57,41 @@ void Region::add(Instruction *I) {
   Scoreboard.add(I);
 }
 
+void Region::setAux(ArrayRef<Instruction *> Aux) {
+  this->Aux = SmallVector<Instruction *>(Aux);
+  auto &LLVMCtx = Ctx.LLVMCtx;
+  for (auto [Idx, I] : enumerate(Aux)) {
+    llvm::ConstantInt *IdxC =
+        llvm::ConstantInt::get(LLVMCtx, llvm::APInt(32, Idx, false));
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RKSimon wrote:

https://discourse.llvm.org/t/second-stage-of-build-on-windows-fails-in-sandboxir/84841
@vporpo - could you replace the APInt with the ConstantInt::get(Type *Ty, uint64_t V, bool isSigned) variant?

https://github.com/llvm/llvm-project/pull/126376