message: NFC: Replace explicit call to `restoreIP` with `InsertPointGuard`
diff: @@ -286,7 +286,7 @@ llvm::AllocaInst* EmitAllocaAtFunctionEntryWithCount(llvm::Type* type,
  absl::string_view name,
  llvm::IRBuilder<>* b,
  int alignment) {
  - llvm::IRBuilder<>::InsertPoint insert_point = b->saveIP();
  + llvm::IRBuilder<>::InsertPointGuard guard(*b);
  llvm::Function* function = b->GetInsertBlock()->getParent();
  b->SetInsertPoint(&function->getEntryBlock(),
  function->getEntryBlock().getFirstInsertionPt());
  @@ -295,7 +295,6 @@ llvm::AllocaInst* EmitAllocaAtFunctionEntryWithCount(llvm::Type* type,
  if (alignment != 0) {
  alloca->setAlignment(alignment);
  }
  - b->restoreIP(insert_point);
  return alloca;
  }
  