John, According to the picture of the instruction, the second operand is a register.
John -----Original Message----- From: IBM Mainframe Assembler List [mailto:[email protected]] On Behalf Of John Ehrman Sent: Monday, February 18, 2013 1:40 PM To: [email protected] Subject: Re: Load and Add Martin Truebner asked: >wouldn't that be ALSI and ALGSI? With LAA/LAAG/LAAL/LAALG the "load >from memory"-part is missing. As I understand the PoP, it says: The second operand is added to the third operand, and the sum is placed at the second-operand location. Subsequently, the original contents of the second operand (prior to the addition) are placed unchanged at the first-operand location. Because the second operand is addressed by a 20-bit displacement, and the first and third operands are in registers, it appears that the 2nd operand is brought from memory, added, and the sum put back. I hope that helps!
