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Assembler Language Reference

sraiq (Shift Right Algebraic Immediate with MQ) Instruction

Purpose

Rotates the contents of a general-purpose register to the left by a specified number of bits, merges the rotated data with a word of 32 sign bits from that general-purpose register under control of a generated mask, and places the rotated word in the MQ Register and the merged result in another general-purpose register.

Note: The sraiq instruction is supported only in the POWER architecture.

Syntax

POWER
sraiq RA,RS,SH
sraiq. RA,RS,SH

Description

The sraiq instruction rotates the contents of the source general-purpose register (GPR) RS to the left by 32 minus N bits, where N is the shift amount specified by SH, merges the rotated data with a word of 32 sign bits from GPR RS under control of a generated mask, and stores the rotated word in the MQ Register and the merged result in GPR RA. A word of 32 sign bits is generated by taking the sign bit of a GPR and repeating it 32 times to make a full word. This word can be either 0x0000 0000 or 0xFFFF FFFF depending on the value of the GPR. The mask consists of N zeros followed by 32 minus N ones.

This instruction then ANDs the rotated data with the complement of the generated mask, ORs the 32-bit result together, and ANDs the bit result with bit 0 of GPR RS to produce the Carry bit (CA).

The sraiq instruction has 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
sraiq None CA 0 None
sraiq. None CA 1 LT,GT,EQ,SO

The two syntax forms of the sraiq instruction always affect the Carry bit (CA) in the Fixed-Point Exception Register. If the syntax form sets the Record (Rc) bit to 1, the instruction affects the Less Than (LT) zero, Greater Than (GT) zero, Equal To (EQ) zero, and Summary Overflow (SO) bits in Condition Register Field 0.

Parameters

RA Specifies target general-purpose register where result of operation is stored.
RS Specifies source general-purpose register for operation.
SH Specifies immediate value for shift amount.

Examples

  1. The following code rotates the contents of GPR 4 to the left by 28 bits, merges the result with 32 sign bits under control of a generated mask, stores the result in GPR 6, and sets the Carry bit in the Fixed-Point Exception Register to reflect the result of the operation:
    # Assume GPR 4 contains 0x9000 3000.
    sraiq 6,4,0x4
    # GPR 6 now contains 0xF900 0300.
    # MQ now contains 0x0900 0300.
  2. The following code rotates the contents of GPR 4 to the left by 28 bits, merges the result with 32 sign bits under control of a generated mask, stores the result in GPR 6, and sets the Carry bit in the Fixed-Point Exception Register and Condition Register Field 0 to reflect the result of the operation:
    # Assume GPR 4 contains 0xB004 3000.
    sraiq. 6,4,0x4
    # GPR 6 now contains 0xFB00 4300.
    # MQ now contains 0x0B00 4300.
    # Condition Register Field 0 now contains 0x8.

Related Information

The addze or aze (Add to Zero Extended) instruction.

Fixed-Point Processor .

Fixed-Point Rotate and Shift Instructions .


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