stxssp

Store VSX Scalar Single-Precision DS-form

stxssp VRS,disp(RA)

Stores a single-precision floating-point value from a VSX register to memory.

Encoding

Binary Layout

0

0:5

VRS

6:10

RA

11:15

DS

16:31

 

Format DS-form

Opcode 0xF4000003

Extension VSX

Operands

• VRS
  VSX Register
• RA
  Source General Purpose Register
• disp
  Displacement Field

Example

stxssp v1, disp(RA)

Related

More in VSX

Reference

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

Description

The instruction stores the double-precision floating-point value in doubleword element 0 of VSR[XS] converted to single-precision format into memory at the effective address (EA). The EA is calculated as the sum of the contents of register RA and the sign-extended DS field. If MSR.VEC=0, a Vector_Unavailable() exception is raised.

Operation

if MSR.VEC=0 then
    Vector_Unavailable()
else if 'stxssp' then
    EA ← (RA|0) + EXTS64(DS||0b00)
    MEM(EA,4) ← bfp32_CONVERT_FROM_BFP64(VSR[VRS+32].dword[0])

Programming Note

The stxssp instruction stores a single-precision floating-point value from the VSX register into memory. Ensure that the Vector Facility is enabled (MSR.VEC=1) to avoid exceptions. The effective address is calculated by adding the contents of RA and the sign-extended DS field. This instruction requires 4-byte alignment for the memory address.