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