mtcrf

Move To Condition Register Fields

mtcrf FXM, RS

Copies bits from a register into the Condition Register, updated only the fields specified by the mask (FXM).

Details

The mfspr instruction moves the contents of a specified Special Purpose Register (SPR) into a general-purpose register RT. If the SPR is 32 bits long, the low-order 32 bits of RT receive the contents, and the high-order 32 bits are set to zero. For SPRs with values from 808 through 811, the instruction is treated as a no-op.

Pseudocode Operation

If FXM[0]=1 then CR0 <- RS[0:3]...

Programming Note

The mtcrf instruction is used to move specific fields of the Condition Register (CR) into general-purpose registers. It's important to note that if the SPR number is between 808 and 811, the instruction acts as a no-op. Ensure that the FXM field correctly specifies which CR fields to transfer to avoid unintended behavior.

Example

mtcrf 0xFF, r3

Encoding

Binary Layout
31
0
RS
6
0
11
FXM
12
144
20
/
31
 
Format XFX-form
Opcode 0x7C000120
Extension Base
Registers Altered CR

Operands

  • FXM
    Field Mask (8 bits)
  • RS
    Source Register