xsiexpqp

VSX Scalar Insert Exponent Quad-Precision

xsiexpqp VRT,VRA,VRB

Inserts the exponent from a doubleword element of one vector register into another vector register.

Encoding

Binary Layout

0:5

VRT

6:10

VRA

11:15

VRB

16:31

Format X-form

Opcode 0xFC0006C8

Extension VSX

Operands

VRT
Target Vector Register
VRA
Source Vector Register
VRB
Source Vector Register

Example

xsiexpqp v1, v2, v3

Registers Altered

MSR

Reference

View in PowerISA v3.1C Specification ↗ OPF Power ISA v3.1C

Description

The contents of bit 0 of VSR[VRA+32] are placed into bit 0 of VSR[VRT+32]. The contents of bits 49:63 of doubleword element 0 of VSR[VRB+32] are placed into bits 1:15 of VSR[VRT+32]. The contents of bits 16:127 of VSR[VRA+32] are placed into bits 16:127 of VSR[VRT+32].

Operation

if MSR.VSX=0 then
    VSX_Unavailable()
else
    VSR[VRT+32].bit[0]     ←VSR[VRA+32].bit[0]
    VSR[VRT+32].bit[1:15] ← VSR[VRB+32].dword[0].bit[49:63]
    VSR[VRT+32].bit[16:127] ←VSR[VRA+32].bit[16:127]

Programming Note

This instruction is used to manipulate the exponent and sign of a quad-precision floating-point number. Ensure that VSX (Vector Scalar Extensions) is enabled in the MSR register before using this instruction; otherwise, it will raise an exception. The operation requires proper alignment of the input registers, specifically for doubleword access in VRB. This instruction operates at the user privilege level and does not generate exceptions under normal conditions.