xsiexpdp

VSX Scalar Insert Exponent Double-Precision

xsiexpdp XT, XA, XB

Inserts exponent from one double into another.

Details

Inserts the exponent bits from XB (bits 0–10) into the exponent field of the significand in XA, placing the result in XT. This operation constructs a double-precision floating-point value by combining a significand with a new exponent. Requires VSX support.

Pseudocode Operation

XT ← (XA[0:51] || XB[0:10])

Programming Note

This instruction can be used to produce a single-precision result. Previous versions of the architecture allowed the contents of doubleword 1 of the result register to be undefined. However, all processors that support this instruction write 0s into doubleword 1 of the result register, as is required by this version of the architecture.

Example

xsiexpdp vs1, vs2, vs3

Encoding

Binary Layout
60
0
XT
6
XA
11
XB
16
219
 
Format XX3-form
Opcode 0xF000072C
Extension VSX
Registers Altered VSR[XT]

Operands

  • XT
    Target
  • XA
    Significand
  • XB
    Exponent
  • RA
    Source General Purpose Register
  • RB
    Source General Purpose Register