This is from http://www.cis.upenn.edu/~milom/cse240-Fall05/handouts/Ch05.pdf , slide 9.
From this diagram, I recognize 0001 as the opcode, which corresponds to the ADD instruction. I recognize 011, or 3, as the source register and 101, or 5, as the destination register. I know that the 1 signifies immediate mode or the second operand is directly in the instruction.
From here, I know that the second operand is 11111 or -1 in decimal and that it will be sign extended (SEXT) before being added to the data in the source register.
Does anyone know what the logical component I highlighted does?
The component is shaped like an isosceles trapezoid, and has three inputs: seemingly, two data inputs and one control input.