RDPID

RDPID — Read Processor ID

Opcode/ Instruction	Op/ En	64/32- bit Mode	CPUID Feature Flag	Description
F3 0F C7 /7 RDPID r32	R	N.E./V	RDPID	Read IA32_TSC_AUX into r32.
F3 0F C7 /7 RDPID r64	R	V/N.E.	RDPID	Read IA32_TSC_AUX into r64.

Op/En	Operand 1	Operand 2	Operand 3	Operand 4
R	ModRM:r/m (w)	NA	NA	NA

Description

Reads the value of the IA32_TSC_AUX MSR (address C0000103H) into the destination register. The value of CS.D and operand-size prefixes (66H and REX.W) do not affect the behavior of the RDPID instruction.

Operation

DEST ← IA32_TSC_AUX 

Flags Affected

None.

Protected Mode Exceptions

\#UD If the LOCK prefix is used. If CPUID.7H.0:ECX.RDPID[bit 22] = 0.

Real-Address Mode Exceptions

Same exceptions as in protected mode.

Virtual-8086 Mode Exceptions

Same exceptions as in protected mode.

Compatibility Mode Exceptions

Same exceptions as in protected mode.

64-Bit Mode Exceptions

Same exceptions as in protected mode.

1.ModRM.MOD = 011B required

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Source: Intel Architecture Software Developer's Manual (July 2017)