AMOADD.W

Atomic Add Word

AMOADD.W rd, rs2, (rs1)

Atomically adds a value to a word in memory.

Details

AMOADD.W atomically loads a word from the address in rs1 into rd, then adds rs2 to it, and stores the result back to that address.

Pseudocode Operation

temp = M[R[rs1]]; M[R[rs1]] = temp + R[rs2]; R[rd] = temp;

Example

AMOADD.W x10, x11, (x12)

Encoding

Binary Layout
00000
31:27
aq
26
rl
25
rs2
24:20
rs1
19:15
010
14:12
rd
11:7
0101111
6:0
 
Format R-Type (Atomic)
Opcode 0x2F
Extension A

Operands

  • rd
    Dest (Old Value)
  • rs2
    Value to Add
  • rs1
    Address