Preheat oven to 375°. Sprinkle pork with 1/8 teaspoon salt and pepper. Place in a 13x9-in. baking dish coated with cooking spray. Whisk preserves, 2 teaspoons rosemary, horseradish and garlic; brush over pork.
Combine sweet potatoes, olive oil and remaining rosemary; place around tenderloin. Sprinkle sweet potatoes with remaining salt.
Bake until a thermometer inserted in pork reads 145°, about 25-30 minutes. Let stand 5 minutes. Slice half of the pork and serve with sweet potatoes. Save remaining pork for Pork with Spanish Rice or another use.