pfalse

SVE Initialize Predicate to False

PFALSE <Pd>.B

Clears all elements of the predicate register.

Details

SVE Initialize Predicate to False clears all elements of the destination predicate register to 0 (false). This SVE instruction is equivalent to PTRUE with pattern 'none' and does not affect PSTATE condition flags. The .B suffix is fixed for this instruction.

Pseudocode Operation

for i = 0 to (VL / 8 - 1):
  Pd[i] ← 0

Example

PFALSE p0.B

Encoding

Binary Layout
00100101
0
0
011000111001
000000
Pd
 
Format SVE Predicate
Opcode 0x2518E400
Extension SVE

Operands

  • Pd
    Destination predicate register (SVE)

Reference (Arm A64 ISA)

Instruction Forms

Encoding Instruction ISA Bit pattern
0x2518E400 PFALSE <Pd>.B A64 00100101 | 0 | 0 | 011000111001 | 000000 | Pd

Description

Set all elements in the destination predicate to false. For programmer convenience, an assembler must also accept predicate-as-counter register name for the destination predicate register.

Operation

CheckSVEEnabled();
constant integer VL = CurrentVL;
constant integer PL = VL DIV 8;
P[d, PL] = Zeros(PL);