1. In large resealable plastic bag, place pork tenderloin, jalapeno, garlic, 1 tablespoon lime juice, pineapple juice, oil, ginger, cumin, and 1/2 teaspoon salt. Refrigerate 2 hours or overnight.
2. Heat oven to 425 degrees F. In medium bowl, combine pineapple, tomato, red onion, cilantro, remaining lime juice, and 1/4 teaspoon salt. Refrigerate salsa until ready to serve.
3. Place tenderloin in foil-lined baking pan. Cook in oven for 30 minutes, or until meat thermometer inserted in center reaches 155 degrees F. Cover with foil and let rest 10 minutes. Internal temperature will rise to 160 degrees F.
4. Warm taco shells according to package directions. Cut pork into slices. Place a few slices of pork into each taco, and top with salsa.