dcmpuq

Decimal Compare Unordered Quad-Precision

dcmpuq BF, vA, vB

Compares two 128-bit DFP numbers (Non-signaling).

Details

The dcmpuq instruction compares two DFP operands in FRA[p] and FRB[p]. The result of the comparison is placed into CR field BF and the FPCC. This instruction handles unordered comparisons, meaning it considers NaNs (Not a Number) as valid values for comparison.

Pseudocode Operation

f1 <- DFP_operation(f2, f3)

Programming Note

Use dcmpuq for comparing two DFP operands while handling unordered cases, which include NaNs. Ensure that the operands are properly aligned and check the FPSCR for exception conditions after execution.

Example

dcmpuq cr0, va, vb

Encoding

Binary Layout
63
0
BF
6
/
9
vA
11
vB
16
642
21
/
31
 
Format X-form
Opcode 0xFC000502
Extension Decimal Floating-Point
Registers Altered FPSCR

Operands

  • BF
    CR Field
  • vA
    Src A
  • vB
    Src B