bic

Bitwise Bit Clear (Shifted Register 64-bit)

BIC <Xd>, <Xn>, <Xm> {, <shift> #<amount>}

ANDs register with NOT of shifted register (64-bit).

Details

64-bit bitwise AND NOT: Xd ← Xn AND NOT (Xm, optionally shifted). The second operand is shifted before the NOT operation is applied. NZCV flags are not affected. This is an AArch64-only instruction.

Pseudocode Operation

operand2 ← DecodeShift(Xm, shift, amount)
Xd ← Xn AND NOT operand2
if Xd[63] == 1 then N ← 1 else N ← 0
if Xd == 0 then Z ← 1 else Z ← 0

Example

BIC x0, x1, x2

Encoding

Binary Layout
1
00
01010
shift
1
Rm
imm6
Rn
Rd
 
Format Logical (Register)
Opcode 0x8A200000
Extension Base

Operands

  • Xd
    Destination 64-bit integer register
  • Xn
    First source / base 64-bit integer register
  • Xm
    Second source / offset 64-bit integer register

Reference (Arm A64 ISA)

Instruction Forms

Encoding Instruction ISA Bit pattern
0x2F009400 BIC <Vd>.<T>, #<imm8>{, LSL #<amount>} A64 0 | Q | 1 | 0111100000 | a | b | c | cmode | 0 | 1 | d | e | f | g | h | Rd
0x2F001400 BIC <Vd>.<T>, #<imm8>{, LSL #<amount>} A64 0 | Q | 1 | 0111100000 | a | b | c | cmode | 0 | 1 | d | e | f | g | h | Rd
0x0E601C00 BIC <Vd>.<T>, <Vn>.<T>, <Vm>.<T> A64 0 | Q | 0 | 01110 | 01 | 1 | Rm | 00011 | 1 | Rn | Rd
0x05800000 BIC <Zdn>.<T>, <Zdn>.<T>, #<const> A64 00000101 | 1 | 0 | 0000 | imm13 | Zdn
0x0A200000 BIC <Wd>, <Wn>, <Wm>{, <shift> #<amount>} A64 0 | 00 | 01010 | shift | 1 | Rm | imm6 | Rn | Rd
0x8A200000 BIC <Xd>, <Xn>, <Xm>{, <shift> #<amount>} A64 1 | 00 | 01010 | shift | 1 | Rm | imm6 | Rn | Rd
0x25004010 BIC <Pd>.B, <Pg>/Z, <Pn>.B, <Pm>.B A64 00100101 | 0 | 0 | 00 | Pm | 01 | Pg | 0 | Pn | 1 | Pd
0x041B0000 BIC <Zdn>.<T>, <Pg>/M, <Zdn>.<T>, <Zm>.<T> A64 00000100 | size | 011 | 01 | 1 | 000 | Pg | Zm | Zdn
0x04E03000 BIC <Zd>.D, <Zn>.D, <Zm>.D A64 00000100 | 1 | 1 | 1 | Zm | 001100 | Zn | Zd

Description

Bitwise Bit Clear (shifted register) performs a bitwise AND of a register value and the complement of an optionally-shifted register value, and writes the result to the destination register.

Operation

bits(datasize) operand1 = X[n, datasize];
bits(datasize) operand2 = ShiftReg(m, shift_type, shift_amount, datasize);
bits(datasize) result;

operand2 = NOT(operand2);

result = operand1 AND operand2;
X[d, datasize] = result;