VSCATTERPF0DPD instruction (AVX512PF)

Forms

Every encoding of VSCATTERPF0DPD that Intel XED knows, one row per XED instruction form (iform). How to read the notation.

Instruction	Encoding	Requires
`VSCATTERPF0DPD vm32y {k}` VSCATTERPF0DPD_MEMf64_MASKmskw_AVX512PF_VL512	`EVEX.512.66.0F38.W1 C6 /5`	AVX512PF

Operation

What the forms do, in pseudocode that our tests run against results recorded on real processors. How to read.

if not cpuid_leaf(7, 0)[1] >> 26 & 1:
    fault(UD)                    # CPUID: no AVX512PF
for i in range(8):               # 8 doubleword indices
    if k1[i]:                    # the elements selected
        a = mem.index.sd[i] * mem.scale
        a += mem.base            # the line that holds byte a may
                                 # come into the first-level cache
                                 # for writing (T0: RFO)
# nothing is written: k1 stays

Run on AMD Zen 5 (EPYC 9645): 1 case. It ran where CPUID reported no AVX512PF, and raised an exception.

Operands

What each form reads and writes, as Intel XED records it: the operands of its syntax, in order, and the implicit ones that the syntax does not name. How to read.

Operand	Kind	Action
`VSCATTERPF0DPD vm32y {k}`
`vm32y`	explicit	read (masked)
`{k}`	explicit	read, write (write mask)

Flags

None: XED records no flag that the forms test or change.

Exceptions

The exception class is XED's name for the set of exception conditions that a form follows. How to read.

All forms: AVX512-E12NP

Attributes

What else XED records about the forms. How to read.

All forms: memory operand only names cache lines; scatter; write masking; memory fault suppression

CPUID and processors

Each form belongs to an XED ISA set. A form can be used when the processor reports every CPUID bit of one of its ISA set's alternatives.

CPUID requirements and processors of the XED ISA sets above. Alternatives are separated by “or”; processors follow XED’s chip model, whose AMD processors end with Zen 2, and the CPU data of this site for Zen 3 to Zen 6.

ISA set	CPUID	Processors
`AVX512PF_512` AVX512PF	AVX512PF `CPUID.(EAX=07H,ECX=0):EBX[26]` AVX512PF	Knights Landing, Knights Mill

VSCATTERPF0DPD