Abstract: In a computer system, a method for executing a Test under Mask instruction in the Fixed Execution Unit (FXU) allows for the execution of these instructions in just one cycle single execution cycle inside the FXU without adding any dedicated data flow circuitry by giving the highest priority to the leftmost selected bit in the operand.

Abstract: A method for allowing a partial instruction to be executed in a fixed point unit pipeline during the instruction dispatch cycle creates a mask used to select which bits of the operands participate in a future logical operation of the fixed point unit back a cycle to the instruction dispatch stage of the fixed point unit. As an S/390 System improvement applicable to other computers, the mask is determined and created two cycles ahead of execution, or two cycles before the mask is actually used. Also, in the method used for moving the mask generation back by one cycle, mask generation overlaps the dispatch stage in the I-unit, and this provides a handshake between the I-unit and E-unit of the fixed point unit of the central processor unit of the computer system. The control setting selection process occurs in a predetermination cycle stage or e-1 (em1) stage for the mask generation and the register file read address.

Abstract: A range check instruction sequence, which performs a logical comparison between two 32-bit values and updates the condition code as a result. It operates identically to the ESA/390 instruction compare logical (CLR) except for the way in which the condition code is set. The new condition code is a function of both the comparison result and the previous condition code. If the first operand is greater than the second operand, the condition code remains unchanged. If the first operand is less than or equal to the second operand, the condition code is set to 2 if it was previously 0 or 1, and is set to 3 if it was previously 2 or 3. This may be understood as advancing the state of the condition code among the groups (0,1), 2, and 3 if the first operand is not greater than the second operand.

Abstract: Special millicode instructions accelerate the "inner loop" portion of a millicode routine to execute ESA/390 string instructions. Specifically, these millicode instructions are: Replicate Byte, Find Byte Equal, Find Byte Not Equal, Compare String Bytes instructions.

Abstract: Disclosed herein is a method of forming cross-linked polymer microspheres, comprising the steps of:forming a reaction mixture essentially free of stabilizer and comprising a polymerization medium, a di-vinyl cross-linking agent, a functional co-monomer which is copolymerizable with said cross-linking agent and a radical initiator, with said cross-linking agent, said functional co-monomer and said initiator being soluble in said polymerization medium;subjecting said reaction mixture to conditions selected to form microspheres with two modes of stabilization, a first being provided by cross-linking, and a second being provided by short stabilizing chains extending outwardly from the microsphere and into said medium, said stabilizing chains having a sufficient concentration of said functional co-monomer to have steric stability in said medium.