Rotates the contents of a general-purpose register to the left by the number of bits specified in another general-purpose register, logically ANDs the rotated data with the generated mask, and stores the result in a third general-purpose register.
See "Extended Mnemonics of Fixed-Point Rotate and Shift Instructions" for more information.
The rlwnm and rlnm instructions rotate the contents of the source general-purpose register (GPR) RS to the left by the number of bits specified by bits 27-31 of GPR RB, logically AND the rotated data with a 32-bit generated mask defined by the values in Mask Begin (MB) and Mask End (ME), and store the result in GPR RA.
Consider the following when using the rlwnm and rlnm instructions:
The BM parameter can also be used to specify the mask for these instructions. The assembler will generate the MB and ME parameters from the BM value.
The rlwnm and rlnm instructions each have two syntax forms. Each syntax form has a different effect on Condition Register Field 0.
|Syntax Form||Overflow Exception (OE)||Fixed-Point Exception Register||Record Bit (Rc)||Condition Register Field 0|
The syntax forms of the rlwnm and rlnm instructions never affect the Fixed-Point Exception Register. If the syntax form sets the Record (Rc) bit to 1, the instructions affect the Less Than (LT) zero, Greater Than (GT) zero, Equal To (EQ) zero, and Summary Overflow (SO) bits in Condition Register Field 0.
|RA||Specifies target general-purpose register where result of operation is stored.|
|RS||Specifies source general-purpose register for operation.|
|RB||Specifies general-purpose register that contains number of bits for rotation of data.|
|MB||Specifies begin value of mask for operation.|
|ME||Specifies end value of mask for operation.|
|SH||Specifies shift value for operation.|
|BM||Specifies value of 32-bit mask.|
# Assume GPR 4 contains 0x9000 3000. # Assume GPR 5 contains 0x0000 0002. # Assume GPR 6 contains 0xFFFF FFFF. rlwnm 6,4,5,0,0x1D # GPR 6 now contains 0x4000 C000. # Under the same conditions # rlwnm 6,4,5,0xFFFFFFFC # will produce the same result.
# Assume GPR 4 contains 0xB004 3000. # Assume GPR 5 contains 0x0000 0002. # Assume GPR 6 contains 0xFFFF FFFF. rlwnm. 6,4,5,0,0x1D # GPR 6 now contains 0xC010 C000. # CRF 0 now contains 0x8. # Under the same conditions # rlwnm. 6,4,5,0xFFFFFFFC # will produce the same result.
Fixed-Point Rotate and Shift Instructions.