VTRUNCB

Operation

Copies the low B field from each W, L, or Q source container.

Assembler Syntax

VTRUNCB.{W|L|Q}(z) Pn(p), Vn(v), Vn(w)

Privilege

Unprivileged

Required CPUID flags

VECTOR

VTRUNCB copies the low B field of each selected W, L, or Q source container into the low B field of the corresponding destination container. For an active container, the destination bytes above that field retain their previous values. An inactive container retains its complete previous destination value. The operation leaves FLAGS unchanged.

An illustrative W-container VTRUNCB view: each active container copies the low source byte into the low destination byte and preserves the old destination high byte; inactive containers preserve the complete old destination value.

VTRUNCB.W low-byte truncation

2.75in

Encodings

VTRUNCB.{W|L|Q}(z) Pn(p), Vn(v), Vn(w)

Format: Instruction format for VTRUNCB.{W|L|Q}(z) Pn(p), Vn(v), Vn(w)

Format: Instruction format for VTRUNCB.{W|L|Q}(z) Pn(p), Vn(v), Vn(w)

size — allowed: 0x1..0x3 [reserved_vector_element_type]