test

Logical Compare

TEST r/m, r

ANDs operands and updates flags (result discarded).

Details

The Logical Compare instruction aNDs operands and updates flags (result discarded).

Pseudocode Operation

// Flags <- DEST AND SRC (result discarded)
// Flags affected: SF, ZF, PF (OF=CF=0)

Example

TEST rbx, rax

Encoding

Binary Layout
84+ow
+0
ModRM
+1
 
Format Legacy
Opcode 84-85
Extension Base

Operands

  • dest
    Register or memory operand
  • src
    General-purpose register