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TRCIDR8

TRCIDR8, Trace ID Register 8

The TRCIDR8 characteristics are:

Purpose

Returns the maximum speculation depth of the instruction trace element stream.

Configuration

External register TRCIDR8 bits [31:0] are architecturally mapped to AArch64 System register TRCIDR8[31:0].

This register is present only when FEAT_ETE is implemented and FEAT_TRC_EXT is implemented. Otherwise, direct accesses to TRCIDR8 are RES0.

Attributes

TRCIDR8 is a 32-bit register.

Field descriptions

31	30	29	28	27	26	25	24	23	22	21	20	19	18	17	16	15	14	13	12	11	10	9	8	7	6	5	4	3	2	1	0
MAXSPEC

MAXSPEC, bits [31:0]

Indicates the maximum speculation depth of the instruction trace element stream. This is the maximum number of P0 elements in the trace element stream that can be speculative at any time.

This field has an IMPLEMENTATION DEFINED value.

Access to this field is RO.

Accessing TRCIDR8

TRCIDR8 can be accessed through the external debug interface:

Component	Offset	Instance
ETE	0x180	TRCIDR8

Accessible as follows:

When OSLockStatus() or !IsTraceCorePowered(), accesses to this register generate an error response.
Otherwise, accesses to this register are RO.

2026-03-26 20:27:25, 2026-03_rel