lfd (Load Floating-Point Double) instruction
Purpose
Loads a doubleword of data from a specified location in memory into a floating-point register.
Syntax
| Bits | Value |
|---|---|
| 0 - 5 | 50 |
| 6 - 10 | FRT |
| 11 - 15 | RA |
| 16 - 31 | D |
Description
The lfd instruction loads a doubleword in storage from a specified location in memory addressed by the effective address (EA) into the target floating-point register (FPR) FRT.
If general-purpose register (GPR) RA is not 0, the EA is the sum of the contents of GPR RA and D, a 16-bit, signed two's complement integer sign-extended to 32 bits. If GPR RA is 0, then the EA is D.
The lfd instruction has one syntax form and does not affect the Floating-Point Status and Control Register or Condition Register Field 0.
Parameters
| Item | Description |
|---|---|
| FRT | Specifies target general-purpose register where result of the operation is stored. |
| D | 16-bit, signed two's complement integer sign-extended to 32 bits for the EA calculation. |
| RA | Specifies source general-purpose register for the EA calculation. |
Examples
The following code loads a doubleword from memory into FPR 6:
.csect data[rw]
storage: .double 0x1
# Assume GPR 5 contains the address of csect data[rw].
.csect text[pr]
lfd 6,storage(5)
# FPR 6 now contains 0x3FF0 0000 0000 0000.