|
| |
Subtract
|
86/88 |
Y |
186 |
Y |
286 |
Y |
386 |
Y |
486 |
Y |
SUB destination, source |
|
Ovfl |
Y |
Dir |
N |
Int |
N |
Trap |
N |
Sign |
Y |
Zero |
Y |
Aux |
Y |
Prty |
Y |
Carry |
Y |
SUB subtracts the source operand from the destination operand and
stores the result in destination. Both operands may be bytes or words,
and both may signed or unsigned binary numbers.
Notes: You may wish to use SBB if you need to subtract
numbers that are larger than 16 bits, since SBB
subtracts a borrow from a previous operation.
You may subtract a byte-length immediate value from
a destination which is a word; in this case, the
byte is sign-extended to 16 bits before the
subtraction.
------------------------------------ Timing ----------------------------------
OpCode Instruction 386 286 86
2C ib SUB AL, imm8 2 3 4
2D iw SUB AX, imm16 2 3 4
2D id SUB EAX, imm32 2
80/5 ib SUB r/m8, imm8 2/7 3/7 4/17+EA
81/5 iw SUB r/m16, imm16 2/7 3/7 4/17+EA
81/5 id SUB r/m32, imm32 2/7
83/5 ib SUB r/m16, imm8 2/7 3/7 4/17+EA
83/5 ib SUB r/m32, imm8 2/7
28/r SUB r/m8, r8 2/7 2/7 3/16+EA
29/r SUB r/m16, r16 2/7 2/7 3/16+EA
29/r SUB r/m32, r32 2/7
2A/r SUB r8, r/m8 2/6 2/7 3/9+EA
2B/r SUB r16, r/m16 2/6 2/7 3/9+EA
2B/r SUB r32, r/m32 2/6
------------------------------------ Logic -----------------------------------
destination = destination - source
See Also SBB DEC NEG CMP AAS DAS Flags |