For the following mathematical expressions write an assembly language code:

(a) For Reg-Reg architecture (10)

(b) For Reg-Mem architecture (10)

U = A + B + D

V = C + D

W= B << 3

X = 7B + B + C+ D

Y = X + V

To tackle the task of writing assembly language code for the given mathematical expressions, we need to consider the two different architectures: Register-Register (Reg-Reg) and Register-Memory (Reg-Mem). Each architecture has its own way of handling data and instructions, which influences how we write the assembly code. Let's break this down step by step.

Assembly Code for Reg-Reg Architecture

In a Register-Register architecture, all operations are performed between registers. This means we need to load values into registers before performing any calculations. Here’s how we can represent the expressions:

• U = A + B + D
• V = C + D
• W = B << 3
• X = 7B + B + C + D
• Y = X + V

Here’s the assembly code for the Reg-Reg architecture:

; Assume A, B, C, D are stored in memory locations
; Load values into registers
LOAD R1, A      ; Load A into R1
LOAD R2, B      ; Load B into R2
LOAD R3, C      ; Load C into R3
LOAD R4, D      ; Load D into R4

; Calculate U = A + B + D
ADD R1, R2      ; R1 = A + B
ADD R1, R4      ; R1 = U = A + B + D

; Calculate V = C + D
ADD R3, R4      ; R3 = V = C + D

; Calculate W = B << 3
SHL R2, 3       ; R2 = W = B << 3

; Calculate X = 7B + B + C + D
MUL R2, 7       ; R2 = 7B
ADD R2, R2      ; R2 = 8B
ADD R2, R3      ; R2 = 8B + C
ADD R2, R4      ; R2 = X = 8B + C + D

; Calculate Y = X + V
ADD R2, R3      ; R2 = Y = X + V

Assembly Code for Reg-Mem Architecture

In a Register-Memory architecture, operations can directly involve memory locations. This allows for a slightly different approach since we can perform operations without needing to load everything into registers first. Here’s how the assembly code would look:

• U = A + B + D
• V = C + D
• W = B << 3
• X = 7B + B + C + D
• Y = X + V

Here’s the assembly code for the Reg-Mem architecture:

; Assume A, B, C, D are stored in memory locations
; Calculate U = A + B + D
LOAD R1, A      ; Load A into R1
ADD R1, B       ; R1 = A + B
ADD R1, D       ; R1 = U = A + B + D
STORE R1, U     ; Store U back to memory

; Calculate V = C + D
LOAD R2, C      ; Load C into R2
ADD R2, D       ; R2 = V = C + D
STORE R2, V     ; Store V back to memory

; Calculate W = B << 3
LOAD R3, B      ; Load B into R3
SHL R3, 3       ; R3 = W = B << 3
STORE R3, W     ; Store W back to memory

; Calculate X = 7B + B + C + D
LOAD R4, B      ; Load B into R4
MUL R4, 7       ; R4 = 7B
ADD R4, B       ; R4 = 8B
LOAD R5, C      ; Load C into R5
ADD R4, R5      ; R4 = 8B + C
LOAD R6, D      ; Load D into R6
ADD R4, R6      ; R4 = X = 8B + C + D
STORE R4, X     ; Store X back to memory

; Calculate Y = X + V
LOAD R7, X      ; Load X into R7
ADD R7, V       ; R7 = Y = X + V
STORE R7, Y     ; Store Y back to memory

In summary, the assembly code varies based on the architecture used. The Reg-Reg architecture focuses on using registers for all operations, while the Reg-Mem architecture allows for direct memory manipulation, which can simplify some operations. Understanding these differences is crucial for efficient programming in assembly language.