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System

PTWRITE

PTWRITE lets software put a value of its own into the Intel Processor Trace stream, for example to mark events in a trace.

CPUID
INTELPT + PTWRITE
CPUID.(EAX=07H,ECX=0):EBX[25]
CPUID.(EAX=14H,ECX=0):EBX[4]
Instructions
1 mnemonic
Processors
Alder Lake, Arrow Lake, Panther Lake, Nova Lake, Sapphire Rapids, Emerald Rapids, Granite Rapids, Diamond Rapids, Goldmont Plus, Tremont, Snow Ridge, Sierra Forest, Clearwater Forest

Intel Processor Trace records the control flow of a program in a compressed stream. PTWRITE adds a value of the program’s own, from a register or memory, as a PTW packet, so that a trace can carry markers or variable values at the points where the program chose to emit them. The packet is written only when tracing is on and configured to record PTWRITE; otherwise the instruction does nothing. The CPUID bit is in leaf 14H, the Processor Trace leaf.

Instructions

Mnemonics with at least one form in PTWRITE. Each page lists all forms of the mnemonic, including those of other extensions.
MnemonicSummaryForms
PTWRITEWrites a 32- or 64-bit value from a register or memory into the Intel Processor Trace stream, when tracing records such packets.2

CPUID and processors

XED splits PTWRITE into 1 ISA set. Software can use a form when the processor reports every CPUID bit of one alternative of the form's ISA set.

XED ISA sets of PTWRITE. 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 setCPUIDProcessors
PTWRITE

INTELPT + PTWRITE
CPUID.(EAX=07H,ECX=0):EBX[25] INTELPT
CPUID.(EAX=14H,ECX=0):EBX[4] PTWRITE

Alder Lake, Arrow Lake, Panther Lake, Nova Lake, Sapphire Rapids, Emerald Rapids, Granite Rapids, Diamond Rapids, Goldmont Plus, Tremont, Snow Ridge, Sierra Forest, Clearwater Forest

Sources

  1. Intel XED v2026.08.23 (commit 0bcb6237345c): forms, encodings, ISA sets, CPUID bits and chip model.
  2. Intel 64 and IA-32 Architectures Software Developer's Manual, Volume 2 (325383-093, September 2026)

The tables are derived from Intel XED, Copyright Intel Corporation, licensed under the Apache License 2.0; x86-64.net converted and reformatted them. The text is our own.